Breast cancer (BC) is among the leading causes of mortality from cancer in women. Many of the available anticancer drugs have various side effects. Therefore, researchers are seeking novel anticancer agents particularly from natural compounds and in this regard, snake venom is still one of the main sources of drug discovery. Previous studies showed potential anticancer effects of Cytotoxin II (CTII) from Naja naja oxiana against the different types of cancers. In this study, a pET-SUMO-CTII vector was transformed into SHuffle® T7 Express, an Escherichia coli strain, for recombinant protein expression (rCTII) and the cytotoxic effects of this protein was assessed in MCF-7 cells. The flow cytometry assay was applied to measure the apoptosis and cell cycle. Also, mRNA levels of the Bax, Bcl2, P53, caspase-3, caspase-8, caspase-9, caspase-10, matrix metalloproteinases (MMP)-3, and MMP-9 were analyzed by quantitative real-time PCR to determine the underlying cellular pathways affected by rCTII. The results of this study showed that treatment with 4 µg mL-1 of rCTII enhanced apoptosis through the intrinsic and extrinsic pathways. Also, the increase of the cells' proportion in the sub-G1 phase as well as a reduction in S phase was observed. In addition, the expression of MMP-3 and MMP-9 was decreased in the treated group in comparison to the control group that may contribute to the reduced migratory ability of tumor cells. These experimental results indicate that rCTII has anti-proliferative potential, and so this protein could be a potential drug for BC therapy in combination with other drugs.

Staphylococci sp. have become the primary pathogens implicated in infective endocarditis, especially within high-income nations. Coupled with the increasing burden of healthcare with aging populations and the protracted course the infections may take, these infections contribute to a significant challenge for healthcare. A systematic review was conducted using relevant search criteria from PubMed, Ovid’s version of MEDLINE, and EMBASE, and data were tabulated from randomized controlled trials (RCT), observational cohort studies, meta-analysis, and basic research articles. The review was registered with the OSF register of systematic reviews and followed the PRISMA reporting guidelines. 35 studies met the inclusion criteria and were included in the final systematic review. The role of Staphylococcus aureus and its interaction with the protective shield and host protection functions is identified and highlighted in several studies. The interaction between infective endocarditis pathogens, vascular endothelium, and blood constituents is also explored giving rise to the potential use of antiplatelets as preventative and/or curative agents. Several factors allow Staphylococcus aureus infections to proliferate within the host with numerous promoting and perpetuating agents. The complex interaction with the hosts' innate immunity also potentiates its virulence. Ameliorating these molecular pathways may serve as a therapeutic avenue for the prevention and treatment of these infections in the near future.

Staphylococci sp. have become the primary pathogens implicated in infective endocarditis, especially within high-income nations. This along with the increasing burden of healthcare, aging populations and the protracted course the infections may take, contribute to a significant challenge for healthcare systems. A systematic review was conducted using relevant search criteria from PubMed, Ovid’s version of MEDLINE, and EMBASE, and data were tabulated from randomized controlled trials (RCT), observational cohort studies, meta-analysis, and basic research articles. The review was registered with the OSF register of systematic reviews and followed the PRISMA reporting guidelines. 35 studies met the inclusion criteria and were included in the final systematic review. The role of Staphylococcus aureus and its interaction with the protective shield and host protection functions was identified and highlighted in several studies. The interaction between infective endocarditis pathogens, vascular endothelium, and blood constituents was also explored giving rise to the potential use of antiplatelets as preventative and/or curative agents. Several factors allow Staphylococcus aureus infections to proliferate within the host with numerous promoting and perpetuating agents. The complex interaction with the hosts' innate immunity also potentiates its virulence. Ameliorating these molecular pathways may serve as a therapeutic avenue for the prevention and treatment of these infections in near future.

The human innate immune response to the pore-forming toxin of Vibrio cholerae VCC, is currently under study. Here, in vitro studies on a human macrophage cell line (THP-1), helped explore the activated pathways involved on the onset the innate immune response towards the cytotoxin. The secreted monomeric 65 KDa form interacts with mature macrophages in pg/ml concentrations, determined by dose response experiments after treatments under 1 h. Non vacuolating concentrations (pg/ml) were applied to the cells; immunoblots revealed activation of MAPKs: early overexpression of p38 and ERK. Cell lysis by release of lactate dehydrogenase (LDH) was not apparent in the first hour, nonetheless it was positive after 24 h. Finally, to discern whether the VCC stimulates transcriptional activators via MAPKs pathway, NF-κB and AP-1 were studied by real time quantitation. Increased expression of p50 (NF-κB), cJun and cFos (AP-1) was observed. Given that NF-κB is the transcription factor initiating inflammation of innate immune response and in turn, AP-1 is responsible for cell surviving response, results from this study lead us to conclude that VCC in vitro treatments, induce a pro-inflammatory and a surviving response, in less than one hour on activated macrophages.

Gastric cancer is a challenging public health concern worldwide and remains a leading cause of cancer-related mortality. The primary risk factor implicated in gastric cancer development is infection with Helicobacter pylori. H. pylori induces chronic inflammation affecting the gastric epithelium, which can lead to DNA damage and promotion of precancerous lesions. Disease manifestations associated with H. pylori are attributed to virulence factors with multiple activities and its capacity to subvert host immunity. One of the most significant H. pylori virulence determinants is the cagPAI gene cluster, which encodes a type IV secretion system and the CagA toxin. This secretion system allows H. pylori to inject the CagA oncoprotein into host cells, causing multiple cellular perturbations. Despite the high prevalence of H. pylori infection, only a small percentage of affected individuals develop significant clinical outcomes, while most remain asymptomatic. Therefore, understanding how H. pylori triggers carcinogenesis and its immune evasion mechanisms is critical in preventing gastric cancer and miti-gating the burden of this life-threatening disease. This review aims to provide an overview of our current under-standing of H. pylori infection, its association with gastric cancer and other gastric diseases, and how it subverts the host immune system to establish persistent infection.

Pathogenicity of many bacteria including Bacillus cereus and Staphylococcus aureus depends on pore-forming toxins (PFTs), which cause lysis of host cells by forming pores in membranes of eukaryotic cells. Bioinformatic analysis revealed in over 600 PFTs a region homologous to the Lys171-Gly250 sequence in hemolysin II (HlyII) from B. cereus, which we designated as “homologous peptide”. Three β-barrel PFTs were used for a detailed comparative analysis. Two of them –HlyII and cytotoxin K2 (CytK2), – are synthesized in Bacillus cereus sensu lato; the third – S. aureus α-toxin (Hla) – is the most investigated representative of the family. Protein modeling showed certain amino acids of homologous peptide to be located on the surface of the monomeric forms of these β-barrel PFTs. We obtained monoclonal antibodies against both a cloned homologous peptide and a 14-membered synthetic peptide DSFNTFYGNQLFMK as part of homologous peptide. The HlyII, CytK2 and Hla regions recognized by the obtained antibodies, as well as an antibody capable of suppressing the hemolytic activity of CytK2, were identified in the course of the work. Antibodies capable of recognizing PFTs of various origins can be useful tools for both identification and suppression of the cytolytic activity of PFTs.