A heterobifunctional reactive oxygen species (ROS)-responsive linker for directed drug assembly onto and delivery from a quantum dot (QD) nanoparticle carrier was synthesized and coupled to doxorubicin using EDC/sulfo-NHS coupling. The doxorubicin conjugate was characterized using ¹H NMR and LC-MS and subsequently reacted under conditions of ROS formation (Cu²⁺/H₂O₂) resulting in successful and rapid thioacetal oxidative cleavage which was monitored using ¹H NMR. The deprotected amine linker is amenable to peptide or protein conjugation prior to QD assembly or to direct conjugation to cognate reactive groups on ligands that cap the QD surface.

The unique structure of G4.0 PAMAM dendrimers allows the drug to be enclosed in internal spaces or immobilized on the surface. In the conducted research, the conditions for the formation of the active G4.0 PAMAM complex with doxorubicin (DOX) were optimized. The physicochemical properties of the system were monitored using DLS, CD, and fluorescence spectroscopy. The QCM-D method was chosen to determine the preferential conditions for the complex formation. The highest binding efficiency of the drug to the cationic dendrimer was observed under basic conditions when the DOX molecule was deprotonated. The decrease in the zeta potential of the complex confirms that DOX immobilizes through electrostatic interaction with the carrier's surface amine groups. The binding constants were determined from the fluorescence quenching of the DOX molecule in the presence of G4.0 PAMAM. The two-fold way of binding doxorubicin in the structure of dendrimers was visible in the ITC isotherm. Fluorescence spectra and release curves identified reversible binding of DOX to the nanocarrier. Among the selected cancer cells, the most promising anticancer activity of G4.0-DOX was observed in A375 malignant melanoma cells. Moreover, the preferred intracellular location of the complexes concerning the free drug was found, which is important from a therapeutic point of view.

Cardiotoxicity is the main side effect of several chemotherapeutic drugs. Doxorubicin (Doxo) is one of the most used anthracyclines in the treatment of many tumors, but the development of acute and chronic cardiotoxicity limits its clinical usefulness. Different studies focused only on the effects of long-term Doxo administration, but recent data show that cardiomyocyte damage is an early event induced by Doxo after a single administration that can be followed by progressive functional decline, that lead to overt heart failure. The knowledge of molecular mechanisms involved in the early stage of Doxo induced cardiotoxicity is of paramount importance to treat and/or prevent it. This review aims to illustrate several mechanisms considered to underlie Doxo-induced cardiotoxicity, such as oxidative and nitrosative stress, inflammation, and mitochondrial dysfunction. Moreover, here we report data from both in vitro and in vivo studies indicating new therapeutic possibilities to prevent Doxo-induced cardiotoxicity.

Pancreatic cancer is the fourth most common cause of cancer mortality worldwide. Furthermore, patients with pancreatic cancer experience limited benefit from current chemotherapeutic approaches because of drug resistance. Therefore, an effective therapeutic strategy for patients with pancreatic cancer is urgently required. Deguelin is a natural chemopreventive drug that exerts potent antiproliferative activity in solid tumors by inducing cell death. However, the molecular mechanisms underlying this activity have not been fully elucidated. Here we show that deguelin blocks autophagy and induces apoptosis in pancreatic cancer cells in vitro. Autophagy induced by doxorubicin plays a protective role in pancreatic cancer cells, and suppressing autophagy by chloroquine or silencing autophagy protein 5 enhanced doxorubicin-induced cell death. Similarly, inhibition of autophagy by deguelin also chemosensitized pancreatic cancer cell lines to doxorubicin. These findings suggest that deguelin has potent anticancer effects against pancreatic cancer and potentiates the anti-cancer effects of doxorubicin. These findings provide evidence that combined treatment with deguelin and doxorubicin represents an effective strategy for treating pancreatic cancer.

Canine Hemangiosarcoma (HSA) is a devastating cancer affecting blood vessels in numerous sites within the body that is primarily seen in middle to older aged dogs. It is marked by its rapid aggressive metastatic pathology that often results in a lack of apparent symptoms in early stages. In most cases, disease becomes apparent due to hemorrhagic events following the rupture of the malignant vascular cell structures that can capture and pool blood cells, resulting in necrosis of the affected tissues. The poor survival times in affected patients cause a hindrance to the ability to carry out large scale studies, leaving numerous knowledge gaps to be filled in future research. The pathologic similarities between this and human angiosarcoma (HA) provides the potential for translatable research to be carried out that would improve outcomes across species. Here, current knowledge is outlined in order to improve understanding HSA holistically and suggest future direction. Emphasis is placed on the potential to improve veterinary practices in ways that will improve the ability to quickly and accurately diagnose patients in order to establish better client communication and provide clarity in collaborating to create the best informed treatment plan possible.

In prostate cancer, p53 maximizes apoptosis in response to severe DNA damage, not DNA replication stress. Here, we examined the apoptotic response of two glioblastoma cells, p53-wild type U87 and a p53-mutated T98G cell, for the same stresses. We ascertained that p53 intensified apoptosis in response to severe DNA damage, not DNA replication stress in glioblastoma. We further asked if p53-mediated apoptosis can be induced by cellular stress other than severe DNA damage. We analyzed two compounds, bortezomib and vorinostat, respective inhibitors of 26S proteasome and histone deacetylase, to evaluate their capacity to activate p53-mediated apoptosis. The cellular stress incited by bortezomib, not vorinostat, activated p53-mediated apoptosis. Next, we asked if the cellular stress generated by combining the two compounds had a synergistic effect on apoptosis. Our results demonstrated that doxorubicin with bortezomib or CFS-1686, or bortezomib with vorinostat have a significant synergistic effect on apoptosis only in p53-wild type cell. Under high stress, p53 translocates from cytosol into the nucleus to cause apoptosis possibly. Together, p53 maximizes apoptosis for cellular stress caused by severe DNA damage, disruption of protein turnover, and for the stress induced by drug combination including doxorubicin with bortezomib or CFS-1686, and bortezomib with vorinostat.

Gold nanoparticles are currently used for the treatment of cancer through a myriad of modalities and delivery approaches. Conjugation of tumor imaging Single Photon Emitting Computed Tomographic (SPECT) radiopharmaceutical to gold nanoparticles will allow systemic targeting and imaging of cancer tissues simultaneously. In this study, gold nanoparticles (AuNPs) were prepared using Epigallocatechingallate (EGCG), loaded with doxorubicin (Dox), and characterized before and after doxorubicin conjugation. Cytotoxicity of EGCG-AuNPs and Dox-EGCG-AuNPs were evaluated against breast carcinoma (MCF-7) and hepatocellular carcinoma (HepG-2) cell lines demonstrating high cytotoxic effects of Dox-EGCG-AuNPs against both cell lines. Doxorubicin was radiolabeled with ^99mTc and our new approach has optimized various labeling conditions resulting in a radiochemical yield of 93.5 ± 2.04%. Biodistribution of ^99mTc-Dox-EGCG-AuNPs was studied in normal and tumor bearing mice following I.V. and intratumoral injections at different time intervals. Results showed high uptake of the intravenously injected ^99mTc-Dox-EGCG-AuNPs in tumor tissue (22.45 %ID/g at 2 h). In addition, localized intratumoral injection of ^99mTc-Dox-EGCG-AuNPs showed extremely high levels of uptake in tumor (80.22 %ID/g at 15 min) with high retention for extended periods post injection. Our results present prospects for the utility of ^99mTc-Dox-EGCG-AuNPs as a multiplexed theranostic agent through SPECT imaging of tumor tissue and therapy through photothermal destruction of cancer tissue through the application of exogenous laser lights as well as through tyrosine phosphatases inhibitor (through EGCG), and topoisomerase II inhibitor (through doxorubicin) effects.

Chemical combinations are believed to reduce drug toxicity, delay cancer cell growth, and achieve enhanced efficacy compared with single active drugs. This research investigated the synergistic effect of DOX and Zm-093, a new sulfonamide derivative, on improving the potential for inducing apoptosis in breast cancer (BC) cell lines. First, the Zm-093 compound was synthesized and its structure was confirmed by FT-IR and NMR. Then, the IC50 values for DOX and Zm-093 were calculated to be 1.21 and 51.24 μM, respectively. To investigate the synergistic effect, Compusyn software was utilized to calculate the combination index (CI). Different methods, including western blotting, flow cytometry, and TUNEL, were used to evaluate the potential synergistic effects of these compounds on inducing apoptosis in MCF-7 cells. Combining the indexes obtained at all concentrations revealed synergistic results. The proapoptotic proteins Bax, tBid, and caspase-3, however, increased 2.4, 3.3, and 5.7 times more than those in the control group. Flow cytometry analysis and the TUNEL method in cells treated with DOX and Zm-093 showed that apoptosis was significantly higher than in other groups. The results confirmed the synergistic effect of DOX and ZM-093 on apoptotic factors expression in MCF-7 cells.

Germline mutations in Breast cancer susceptibility gene 1 and 2 (BRCA1 and BRCA2) cause breast, ovarian and other cancers, and the chemotherapeutic drug doxorubicin (Dox) is widely used to treat these cancers. However, Dox use is limited by latent induction of severe cardiotoxicity known as Dox-induced cardiomyopathy, for which there are no specific treatments currently available. Dox is administered into the systemic circulation, where it readily translocates into sub-cellular compartments, and disrupts the integrity of DNA. Accumulating evidence indicates that oxidative stress, DNA damage, inflammation and apoptosis all play a central role in Dox-induced cardiomyopathy. The BRCA1 and BRCA2 proteins are distinct as they perform crucial yet separate roles in the homologous recombination repair of DNA double-strand breaks, thereby maintaining genomic integrity. Additionally, both BRCA1 and BRCA2 mitigate oxidative stress and apoptosis in both cardiomyocytes and endothelial cells. Accordingly, BRCA1 and BRCA2 are essential regulators of pathways that are central to the development of cardiomyopathy induced by Doxorubicin. Despite extensive investigations, there exists a gap in knowledge about the role of BRCA1 and BRCA2 in Doxorubicin-induced cardiomyopathy. Here, we review the previous findings and associations about the expected role and associated mechanisms of BRCA1 and 2 in Dox-induced cardiomyopathy and future perspectives.

Tailoring extracellular vesicles (EVs) as targeted drug delivery systems to enhance the therapeutic efficacy showed superior advantage over liposomal therapies. Herein, we developed a novel nanotool for targeting B16.F10 murine melanoma, based on EVs stabilized with Polyethylene glycol (PEG) and loaded with doxorubicin (DOX). Nanosized EVs were efficiently enriched from melanoma cells cultured under metabolic stress by ultrafiltration coupled with size exclusion chromatography (UF-SEC) and characterized by size, morphology, and proteome. To reduce their clearance in vivo, EVs were PEGylated and passively loaded with DOX (PEG-EV-DOX). Our data suggested that the low PEG coverage of EVs might still favor EV surface protein interactions with target proteins from intratumor cells, ensuring their use as “Trojan horses” to deliver DOX to the tumor tissue. Moreover, our results showed a superior antitumor activity of PEG-EV-DOX in B16.F10 murine melanoma models in vitro and in vivo compared to that exerted by clinically applied liposomal DOX in the same tumor model. The PEG-EV-DOX administration in vivo reduced NF-κB activation and increased BAX expression, suggesting better prognosis of EV-based therapy than liposomal DOX treatment. Collectively, our results highlight the promising potential of EVs as optimal tools for systemic delivery of DOX to solid tumors.

Recent advancements in nanotechnology have led to the development of multifunctional iron oxide nanoparticles, presenting new opportunities in cancer therapy. This study aimed to synthesize and evaluate citric acid-coated/ folic acid conjugated nanoparticles loaded with doxorubi-cin and investigate their efficacy in experimental tumor models. For synthesis, controlled co-precipitation method was employed to produce highly dispersive, multifunctional nanofluids with a narrow size distribution of iron oxide nanoparticles. Nanoparticles were characterized using Dynamic Light Scattering (DLS) and Electrophoretic Light Scattering (ELS) for size distribution and zeta potential, X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) for structure and morphology, Vibrating Sample Magnetometry (VSM) for magnetic properties, and UV-Visible (UV-Vis) and Fourier-Transform Infra-red (FTIR) spectroscopy for modification confirmation. In vitro experiments employed RM1 (prostate cancer) and MEC1 (Chronic lymphocytic leukemia) cell lines to assess cytotoxicity and drug delivery efficiency. Fluorescence microscopy confirmed the intracellular delivery of doxorubicin by these nanoparticles, highlighting their potential for targeted therapy. As a result, nanoparticles conjugated with folic acid showed reduced efficacy over time. This study underscores the critical role of nanoparticle modifications in optimizing therapeutic outcomes. Future research should focus on further refining nanoparticle formulations and long-term effects in vivo, for development of effective and safe agents for targeted cancer treatment.

Classical Hodgkin lymphoma (cHL) is a highly curable disease (70-80%), even though long-term toxicities, drug resistance, and predicting clinical responses to therapy are major challenges in cHL treatment. To solve these problems, we characterized two cHL cell lines with acquired resistance to doxorubicin, KM-H2dx and HDLM-2dx (HRSdx), generated from KM-H2 and HDLM-2 cells, respectively. HRSdx cells developed cross-resistance to vinblastine, bendamustin, cisplatin, dacarbazine, gem-citabine, brentuximab vedotin (BV), and γ-radiation. Both HDLM-2 and HDLM-2dx cells had an intrinsic resistance to BV but not to the drug MMAE. HDLM-2dx acquired cross-resistance to caelyx. HRSdx cells had in common: decreased CD71, CD80, CD54, cyt-ROS, HLA-DR, DDR1, CD44; increased Bcl-2, CD58, COX2, CD26, CCR5, invasive capability; increased CCL5, TARC, PGE2, TGF-β, and capability to hijack monocytes. In HRSdx cells, less sensitive to DNA damage and oxidative stress, the efflux drug transporters MDR1 and MRP1 were not up-regulated, and doxorubicin accumulated in cytoplasm rather than in nucleus. Both autophagy inhibitor chloroquine and extracellular vesicles (EVs) release inhibitor GW4869 enhanced doxorubicin activity and counteracted doxorubicin resistance. In conclusion, this study identifies common modulated antigens in HRSdx cells, the associated cross-resistance patterns, and new potential therapeutic options to enhance doxorubicin activity and overcome resistance.

Doxorubicin (Dox) is a commonly used chemotherapeutic that can adversely affect skeletal muscle, including causing muscle atrophy. Dox is known to induce an event known as mitochondrial permeability transition (MPT) in cardiac muscle and this plays an important role in Dox-mediated cardiac toxicity. Further to this, recent evidence identifies MPT as a mechanism of atrophy in skeletal muscle, suggesting that MPT may underlie some of the Dox-related toxicity in skeletal muscle. To test this hypothesis, we used cultured human primary myotubes, C2C12 myotubes, and single adult mouse flexor digitorum brevis (FDB) muscle fibers in experiments involving Dox treatment with or without inhibitors of MPT. Dox treatment of myotubes caused myonuclear translocation of the mitochondrial protein apoptosis inducing factor (AIF) and increased mitochondrial reactive oxygen species (mROS), consistent with the known consequences of MPT. Furthermore, Dox caused atrophy in C2C12 myotubes grown on patterned plates, human primary myotubes, and single muscle fibers from adult mice. Notably, Dox-induced atrophy could be prevented by a wide variety of agents that inhibit MPT, as well as by inhibiting mROS or Caspase 3. In conclusion, our results indicate that MPT plays an important role in driving Dox-mediated skeletal muscle atrophy.

P-glycoprotein (Pgp) determines resistance to a broad spectrum of drugs in glioblastoma multiforme (GB) because it is highly expressed in GB stem cells and in brain-blood barrier (BBB), the peculiar endothelium surrounding brain. Inhibiting Pgp activity in BBB and GB is still an open challenge. Here, we tested the efficacy of a small library of tetrahydroisoquinoline derivatives with an EC₅₀ for Pgp < 50 nM, in primary human BBB cells and in patients-derived GB, from which we isolated differentiated/adherent cells (AC, i.e. Pgp-negative/doxorubicin-sensitive cells) and stem cells (neurospheres, NS, i.e. Pgp-positive/doxorubicin-resistant cells). At 1 nM, 3 compounds increased the delivery of doxorubicin, a typical substrate of Pgp, across BBB monolayer, without altering expression and activity of other transporters. The compounds increased the drug accumulation within NS, restoring necrosis, apoptosis and reduction in cell viability induced by doxorubicin. In co-culture systems, the compounds added to the luminal face of BBB increased the delivery of doxorubicin to NS growing under BBB and rescued the drug’s cytotoxicity. Our work identified new ligands of Pgp active at low nanomolar concentrations, that effectively reduce Pgp activity in BBB and GB, and can improve chemotherapy efficacy in this tumor.

Hybrid microparticles based on an iron core and amphiphilic shell have been prepared to respond simultaneously to external (magnetic and ultrasounds field) and internal (pH) stimuli for delivery of the anticancer drug doxorubicin. The microparticles have been prepared in three main steps; including surface modification of the iron core followed by conjugation with the amphiphilic chitosan and drug loading. The particles demonstrate spherical shape and dimension in the range 1-3 m with tunable surface charge by changing the pH of surrounding environment. The microparticles demonstrate good stability in simulated physiological solutions and able to allocate up to 400 g of drug per mg of bare carrier. The response to ultrasound and the changes in the shell structure when exposed to different pH allows to control the doxorubicin release. In vitro cytotoxicity tests performed on fibloblast NIH/3T3 demonstrate a reduction in the cell viability when doxorubicin was administrated by microparticles compared to the free formulation; in particular when ultrasound were applied. The bare microparticles demonstrate cytocompatibility and hemocompatibility up to 50g/mL and 60 g/mL, respectively.

Currently, the most promising work seems to be aimed not so much at the development of new drugs, but rather at creating ways of targeted delivery of existing drugs. In this paper, we show that polymeric micelles based on chitosan, heparin grafted with lipoic and oleic acids residues demonstrate the potential for doxorubicin delivery to tumors due to pH-, glutathione-sensitivity. Smart delivery systems use the Aikido principle, i.e. they target tumor cells according to their features. Natural polysaccharides (heparin and chitosan) provide the pH sensitivity of micelles: the release of doxorubicin (Dox) is enhanced in a slightly acidic environment (model tumor microenvironment). Fatty acid residues are necessary for the formation of micelles and solubilization of cytostatics in a hydrophobic core. Lipoic acid residues formed a labile S-S cross-linking between polymer chains (the first method), and also covalently attached doxorubicin molecules through glutathione-sensitive S-S bridges (the second option) – determine Redox sensitivity of micelles to tumors. The characterization of polymeric micelles and prodrugs (Dox-polymer) was carried out using FTIR spectroscopy. The release of doxorubicin from micelles occurs slowly (20% / 6h) in an environment with a pH of 7.4 and the absence of glutathione, while in a slightly acidic environment and in the presence of 10 mM glutathione, the rate increases up 6 times, with an increase in the effective concentration up to 5 times after 7 h. The permeability of free doxorubicin, micellar formulations (covalent S-S crosslinked and not) into Raji, K562, A875 cancer cells was studied using confocal laser scanning microscopy (CLSM), demonstrated an increase in the permeability of micellar formulations based on Dox. Thus, we have presented micellar formulations of doxorubicin for targeted delivery to tumor, what is important in the aspects of reducing non-target toxicity, increasing the selectivity of cytostatics against tumors and overcome multidrug resistance.

Canine mammary tumors represent one of the leading malignant pathology in female dogs, displaying the importance of efficient therapeutic findings, beside the golden standard surgery, able to limit the development of the disease. Studies in human cancers demonstrated that Doxorubicin presents a good effect in different biological processes like apoptosis, autophagy, cell cycle, cell invasion and epithelial to mesenchymal transition. Our study following the effects of Doxorubicin on two canine mammary cancer cell lines P114 and CMT-U27, showing an inhibitory effect in cell proliferation and an expression alteration of the EMT related genes.

Hydrogels can offer many opportunities for drug delivery strategies. They can be used on their own or their benefits can be further exploited in combination with other nanocarriers. Intelligent hydrogels that react to changes in the surrounding environment can be utilized as gatekeepers and provide sustained on demand drug release. In this study, a hybrid nanosystem for tempera-ture and pH sensitive delivery was prepared from MCM-41 nanoparticles grafted with newly synthesized thermosensitive hydrogel (MCM-41/AA-g-PnVCL). The initial particles were chemi-cally modified by carboxyl groups attachment. Later, they were grafted with agar (AA) and vi-nylcaprolactam (VCL) by free radical polymerization. Doxorubicin was applied as a model hy-drophilic chemotherapeutic drug. The successful formulation was confirmed by FT-IR and TGA. Transmission electron microscopy and dynamic light scattering analysis showed small particles with negative zeta potential. Their release behaviour was investigated in vitro in different pH media and at different temperatures. At tumor simulating conditions (40ºC and pH 4.0) doxoru-bicin was almost completely released within 72 hours. The biocompatibility of the proposed na-noparticles was demonstrated by in vitro haemolysis assay. These results suggest the possible parenteral application of the newly prepared hydrogel-functionalized mesoporous silica nanopar-ticles for temperature-sensitive and pH-triggered drug delivery at the tumor site.

Doxorubicin, a member of the anthracycline family, is a common anticancer agent often used as a first line treatment for the wide spectrum of cancers. Doxorubicin-based chemotherapy, although effective, is associated with serious side effects, such as irreversible cardiotoxicity or nephrotoxicity. Those often life-threatening adverse risks, responsible for the elongation of the patients' recuperation period and increasing medical expenses, have prompted the need for creating novel and safer drug delivery systems. Among many proposed concepts, polymeric nanocarriers are shown to be a promising approach, allowing for controlled and selective drug delivery simultaneously enhancing its activity towards cancerous cells and reducing toxic effects on healthy tissues. This article is a chronological examination of the history of the work progress on polymeric nanostructures, designed as efficient doxorubicin nanocarriers, with the emphasis on the main achievements of 2010-2020. Numerous publications have been reviewed to provide an essential summation of the nanopolymer types and their essential properties, mechanisms towards efficient drug delivery, as well as active targeting stimuli-responsive strategies that are currently utilized in the doxorubicin transportation field.

Background: Breast cancer is the leading cause of cancer mortality and morbidity among Indonesian women. Identification of biological pathways leading into therapeutic resistance through in vitro model is an important step to develop alternative effective therapy in breast cancer. Loss of PTEN expression has been associated with resistance to chemotherapy by involving PI3K/PTEN- dependent apoptosis pathway. We conducted in vitro experiment to investigate the association of hsa-miR-21 and PTEN expression in Doxorubicin-resistant MCF-7 cell line. Methods: Parental MCF-7 cells were periodically incubated with Doxorubicin to obtain specific Dox-resistant variant determined by IC50 using MTT assay. PTEN protein expression was analyzed using immunocytochemistry. Expression of mature has-miR-21 was measured using qRT-PCR. Results: The IC50 of Doxorubicin in parental MCF-7 and Doxorubicin-resistant MCF-7 cells (MCF-7/Dox) was 0.68 and 5.78 µg/ml, respectively. Hsa-miR-21 was significantly overexpressed in MCF-7/Dox cells compared to parental MCF cells (7.94 fold changes). Conclusion: PTEN and hsa-miR-21 expression levels were negatively correlated in Doxorubicin resistant-MCF cells. Further study to confirm the causal relationship of miR-21 overexpression and PTEN downregulation in MCF-7/Dox is required.

Chromatin is dynamically remodeled to adapt to all DNA-related processes, including DNA damage responses (DDR). This adaptation requires DNA and histone epigenetic modifications, which are mediated by several types of enzymes; among them are lysine methyltransferases (KMTs). Methods: KMT inhibitors, chaetocin and tazemetostat (TZM), were used to study their role in the DDR induced by ionizing radiation or doxorubicin in two human sarcoma cells lines. The effect of these KMT inhibitors was tested by the analysis of chromatin epigenetic modifications, H4K16ac and H4K20me2. DDR was monitored by the formation of γH2AX, MDC1, NBS1 and 53BP1 foci, and the induction of apoptosis. Results: Chaetocin and tazemetostat treatments caused a significant increase of H4K16 acetylation, associated with chromatin relaxation; and increased DNA damage, detected by the labeling of free DNA-ends. These inhibitors significantly reduced H4K20 dimethylation levels in response to DNA damage and impaired the recruitment of 53BP1, but not of MDC1 and NBS1, at DNA damaged sites. This modification of epigenetic marks prevents DNA repair by the NHEJ pathway and leads to cell death. Conclusion: KMT inhibitors can function as sensitizers to DNA damage-based therapies and be used in novel synthetic lethality strategies for sarcoma treatment.

Slow and controlled release systems for drugs, have attracted increasing interest recently. A highly efficient metal-organic gels (MOGs) drug delivery carrier, i.e., MIL-100(Al) gels, has been fabricated by a facile, low cost and environment friendly one-pot process. The unique structure of MIL-100(Al) gels leads to a high loading efficiency (620 mg/g) towards doxorubicin hydrochloride (DOX) as a kind of anticancer drugs. DOX-loaded MOGs exhibited high stability under physiological conditions and sustained release capacity of DOX for up to 3 days (under acidic environments). They further showed sustained drug release behavior and excellent antitumor effects in in vitro experiments on HeLa cells, in contrast with the extremely low biotoxicity of MOGs. Our work provides a promising way for the anticancer therapy, by utilizing this MOGs-based drug delivery system, as an efficient and safe vehicle.

Glioblastomas (GBM) are most common, primary brain tumors in adults. Despite advances in neurosurgery, radio- and chemotherapy, the median survival of GBM patients is 15 months. Recent large-scale genomic, transcriptomic and epigenetic analyses have shown the cellular and molecular heterogeneity of GBMs, which hampers the outcomes of standard therapies. We have established 13 GBM-derived cell cultures from fresh tumor specimens and characterized them molecularly using RNAseq, immunoblotting and immunocytochemistry. Evaluation of proneural (OLIG2, IDH1R132H, TP53 and PDGFRα), classical (EGFR) and mesenchymal markers (CHI3L1/YKL40, CD44 and phospho-STAT3), as well as expression of pluripotency (SOX2, OLIG2, NESTIN) and differentiation (GFAP, MAP2, β-Tubulin III) markers revealed the striking inter-tumor heterogeneity of primary GBM cell cultures. Upregulated expression of VIMENTIN, N-CADHERIN and CD44 at mRNA/protein levels suggested increased epithelial to mesenchymal transition (EMT) in most studied cell cultures. The effects of temozolomide (TMZ) or doxorubicin (DOX) were tested in three GBM-derived cell cultures with different methylation status of the MGMT promoter. Amongst TMZ- or DOX-treated cultures the strongest accumulation of apoptotic markers: caspase 7 and PARP were found in WG4 cells with methylated MGMT suggesting that its methylation status predicts vulnerability to both drugs. As many GBM-derived cells showed high EGFR levels, we tested the effects of AG1478, an EGFR inhibitor, on downstream signaling pathways. AG1478 caused decreased levels of phospho-STAT3, thus inhibition of active STAT3 augmented antitumor effects of DOX and TMZ in cells with methylated and intermediate status of MGMT. Altogether, our findings show that GBM-derived cell cultures mimic the considerable tumor heterogeneity and identifying patient-specific signaling vulnerabilities can assist in overcoming therapy resistance, by providing personalized combinatorial treatment recommendations.

We evaluated the mono- and combination-therapy effects of valproic acid (VPA) and doxorubicin (DOX) in hepatocellular carcinoma (HCC) and identified a specific and efficient, synergistic anti-proliferative effect of the VPA and DOX combination in HCC cells, especially HepG2 cells; this effect was not apparent in MIHA cells, a normal hepatocyte cell line. The calculation of the coefficient of drug interaction confirmed the significant synergistic effect of the combination treatment. Concurrently, the synergistic apoptotic cell death caused by the VPA and DOX combination treatment was confirmed by Hoechst nuclear staining and western blot analysis of caspase-3 and poly (ADP-ribose) polymerase (PARP) activation. Co-treatment with VPA and DOX enhanced reactive oxygen species (ROS) generation and autophagy, which were clearly attenuated by ROS and autophagy inhibitors, respectively. Furthermore, as an indication of the mechanism underlying the synergistic effect, we observed that DOX internalization, which was induced in the VPA and DOX combination-treated group, occurred via by the caveolae-mediated endocytosis pathway. Taken together, our study uncovered the potential effect of the VPA and DOX combination treatment with regard to cell death, including induction of cellular ROS, autophagy, and the caveolae-mediated endocytosis pathway. Therefore, these results present novel implications in drug delivery research for the treatment of HCC.

Nanosized drug delivery systems (DDS) have been studied as a novel strategy against cancer due to their potential to simultaneously decrease drug inactivation and systemic toxicity and increase passive and/or active drug accumulation within the tumor(s). Triterpenes are plant-derived compounds with interesting therapeutic properties. Betulinic acid (BeA) is a pentacyclic triterpene which has great cytotoxic activity against different cancer types. Herein, we developed a nanosized protein-based DDS of bovine serum albumin (BSA) as the drug carrier combining two compounds: doxorubicin (Dox) and the triterpene BeA using an oil-water-like micro-emulsion method. Spectrophotometric assays were performed to determine protein and drug concentrations in the DDS. The biophysical properties of these DDS were characterized using dynamic light scattering (DLS) and circular dichroism (CD) spectroscopy confirming nanoparticle (NP) formation and drug loading into the protein structure, respectively. The encapsulation efficiency was 77% for Dox and 18% for BeA. More than 50% of both drugs were released within 24 h, at pH 6.8, while less drug was released at pH 7.4 in this time period. Co-incubation viability assays of Dox and BeA alone for 24 h demonstrated synergistic cytotoxic activity in the low μM range against the non-small cell lung carcinoma (NSCLC) A549 cells. Viability assays of the BSA(Dox+BeA) DDS demonstrated a higher synergistic cytotoxic activity than the two drugs with no carrier. Moreover, confocal microscopy analysis confirmed cellular internalization of the DDS and nucleus accumulation of the Dox. We determined the mechanism of action of the BSA(Dox+BeA) DDS, confirming S-phase cell cycle arrest, DNA damage, caspase cascade activation, and downregulation of the epidermal growth factor receptor (EGFR) expression. This DDS has the potential to synergistically maximize the therapeutic effect of Dox and diminish chemoresistance induced by EGFR expression using a natural triterpene against NSCLC.

Doxorubicin (DOX) is a frequently used chemotherapeutic drug for breast cancer, but its site specificity and local internalization into tumor cells is rather low. In this paper we conjugated magnetic nanoparticles (MNPs) with DOX and/or a pseudopeptide NucAnt (N6L) as modality to enhance DOX-induced antitumor effects in breast cancer cells (BT474). In this context, we determined cellular uptake of MNP formulations, analyzed cell viability and expression of apoptotic and cell cycle proteins after magnetic hyperthermia (43°C, 1 h) in vivo and in vitro. We have shown that i) the presence of N6L on the surface of DOX-functionalized MNPs increases their internalization into a target cells and potentiates the cytotoxic potential of the anticancer drug, ii) in combination with hyperthermia, DOX functionalized MNPs influence the expression of apoptotic and cell cycle proteins, and also favors tumor regression in vivo. Our data show that intratumoral application of DOX coupled MNPs is able to overcome biological barriers to chemotherapeutic drugs, enabling them to penetrate into the target cells. Combined with hyperthermia these MNPs can be an effective method in enhancing the localised delivery and penetration of DOX into breast cancer cells.

(1) Background: This case report focuses on a 46-year-old female patient diagnosed with a rare and aggressive form of breast cancer known as rapidly growing, ulcerated breast cancer. The patient exhibited rapid progression of the disease, experiencing discomfort and noticeable changes in the size and texture of the affected breast over a short period of time; (2) Methods: An intensive neoadjuvant chemotherapy regimen was employed as the primary treatment approach. The patient's response to this treatment was closely monitored and assessed. Various diagnostic tests and imaging techniques were utilized to evaluate the extent of the disease and track its response to the chemotherapy; (3) Results: The patient's response to the neoadjuvant chemotherapy regimen was remarkable, resulting in a complete pathologic response. This outcome, although unusual in rapidly growing, ulcerated breast cancers, highlights the effectiveness of neoadjuvant chemotherapy in managing large, locally advanced breast cancers; (4) Conclusions: The multidisciplinary approach employed in managing this complex breast cancer case proved to be crucial to the patient's favorable outcome. Despite the aggressive nature of the disease and the challenges posed by the rapid growth and ulceration, the patient achieved a positive result. This case contributes to the limited clinical literature on such unusual and aggressive breast cancer cases, providing valuable insights for future clinical practice.8

In this paper, mesoporous electrodes consisted of Sb-doped SnO2 deposited onto Ti plates controlled corroded under acidic medium were synthesized by spin-coating method, and morpho structurally characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrodes were electrochemical testing in the degradation/mineralization by electrooxidation (EO) of doxorubicin (DOX) as single-component and multi-component together with capecitabine (CCB)-from cytostatic class and humic acid (HA)-from natural organic matter (NOM) class in the absence/the presence of activated carbon (AC) as particulate electrode. The best mineralization efficiency of 67 % was achieved for DOX mineralization using Sb-doped SnO2 deposited onto Ti plate controlled corroded with oxalic acid in electrooxidation process. The presence of AC within the electrolysis process generated a synergy effect of 52.75 % for TOC parameter removal, which is in accordance and quite better than the result reported in the literature. The aspects related to the complex mechanism of DOX degradation and mineralization are discussed. The superiority of AC assisted electrooxidation, as electrochemical filtering (EF), was proved considering simultaneous degradation and mineralization of mixture of doxorubicin, capecitabine and humic acid.

Because of their high biocompatibility, stability, ability to negotiate biological barrier passage, and functionalization properties, biological nanoparticles have been actively investigated for many medical applications. Biological nanoparticles, including natural extracellular vesicles (EVs) and synthetic extracellular vesicle-mimetic nanovesicles (EMNVs) represent novel drug delivery vehicles that can accommodate different payloads. In this study, we investigated EVs and EMNVs for their physical, biological and delivery properties and we showed that EMNVs have similar delivery properties compared to EVs. In addition, these nanotherapeutics were analyzed for their cytostatic properties in combination with the FDA-approved drug hydroxychloroquine (HCQ), which increased their cytostatic thanks to its lysosome-destabilizing properties. Altogether, these data demonstrated that, at least in vitro, the use of synthetic biomimetic particles is comparable to the natural counterparts, while their synthesis is significantly faster and more cost effective. In addition, we highlighted the benefits of combining biological nanoparticles with a lysosome destabilizing agent that increased the delivery properties of the particles.

The microbiome is capable of modulating the bioavailability of chemotherapy drugs mainly due to metabolizing these agents. Multiple cytostatic bacterial metabolites were recently identified that have cytostatic properties on cancer cells. In this study we addressed the question whether the cytostatic bacterial metabolites (cadaverine, indolepropionic acid, indoxylsulfate) can interfere with the cytostatic effects of the chemotherapy agents used in the management of breast cancer (doxorubicin, gemcitabine, irinotecan, methotrexate, rucaparib, 5-fluorouracil, paclitaxel). The chemotherapy drugs were applied in a wide concentration range to which a bacterial metabolite was added in a concentration within its serum reference range and the effects on cell proliferation were assessed. There was no interference between doxorubicin, gemcitabine, irinotecan, methotrexate, rucaparib and the bacterial metabolites. Nevertheless, cadaverine increased the Hill coefficient of the inhibitory curve of 5-fluorouracil and indolepropionic acid increased the IC50 value of 5-fluorouracil that are either disadvantageous effects or effects of unknown significance. Nevertheless, indolepropionic acid decreased the IC50 value of paclitaxel that is a potentially advantageous combination.

Programmed cell death 4 (Pdcd4) is a tumor suppressor, which has been demonstrated to efficiently suppress tumorigenesis. Biochemically, Pdcd4 binds with translation initiation factor 4A and represses protein translation. Beyond its role in tumor suppression, increasing evidence indicates that Pdcd4 enhances the chemosensitivity of several chemotherapeutic drugs. To date, several translational targets of Pdcd4 have been identified. These targets govern important signal transduction pathways, and their attenuation may enhance chemosensitivity or overcome drug resistance. This review will discuss the signal transduction pathways regulated by Pdcd4 and the potential mechanisms through which Pdcd4 enhances chemosensitivity or counteracts drug resistance.

Colonization of distant organs by tumor cells is a critical step of cancer progression. The initial avascular stage of this process (micrometastasis) remains almost inaccessible to study due to the lack of relevant experimental approaches. Here, we introduce an in vitro/in vivo model of organ-specific micrometastases of triple-negative breast cancer (TNBC) that is fully implemented in a cost-efficient chick embryo (CE) experimental platform. The model is built as three-dimensional (3D) tissue engineering constructs (TECs) combining human MDA-MB-231 cells and decellular-ized CE organ-specific scaffolds. TNBC cells colonized CE organ-specific scaffolds in 2-3 weeks, forming tissue-like structures. The feasibility of this methodology for basic cancer research, drug development and nanomedicine was demonstrated on a model of hepatic micrometastasis of TNBC. We revealed that MDA-MB-231 differentially colonize parenchymal and stromal com-partments of the liver-specific extracellular matrix (LS-ECM) and become more resistant to the treatment with molecular Doxorubicin (Dox) and Dox-loaded mesoporous silica nanoparticles than in monolayer cultures. When grafted on CE chorioallantoic membrane, LS-ECM-based TECs induced angiogenic switch. These findings may have important implications for the diag-nosis and treatment of TNBC. The methodology established here is scalable and adaptable for pharmacological testing and cancer biology research of various metastatic and primary tumors.