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.

High incidence of epithelial malignancies in HIV-1 infection is associated with co-infection with oncogenic viruses, such as high-risk human papillomaviruses (HR HPVs), most often HPV16. A collaboration between HIV-1 and HR HPVs in the malignant transformation of epithelial cells exposed to both viruses have long been anticipated. Here, we delineated the effects on in vitro and in vivo properties of HPV16-infected cervical cancer cells of HIV-1 reverse transcriptase. Epidermoid carcinoma Ca Ski cells were made to express RT of HIV-1 clade A (RT_A) or Green Fluorescence Protein (GFP) by lentiviral transduction, subclones with one or six copies of RT_A and six copies of GFP DNA were generated. Expression by subclones of GFP was assessed by flow cytometry, and of RT_A, by Western blotting. Cells were assessed for the levels of mRNA of the RT_A, E6 and its isoforms, and cellular factors characterizing oxidative stress, and EMT by the real-time PCR. Parameters of glycolysis and mitochondrial respiration were assessed by Seahorse technology. Subclones were surveyed for the changes in cell cycle, doubling time, migration capacity, clonogenic activity and for the capacity to form tumors in nude mice. Ca Ski RT_A produced 20-55 fg of RT_A per cell. Expression of RT_A caused a proportional increase in the expression of E6*I isoform. In Ca Ski, RT_A suppressed mitochondrial respiration and oxygen consumption, and increased glycolysis. Compared to parental cells and GFP control, transcription in Ca Ski RT_A of epithelial (E-CADHERIN) state marker was increased, and of mesenchymal (VIMENTIN) decreased, indicating acquisition by cells of the hybrid epithelial/mesenchymal (E/M) phenotype. While Ca Ski GFP and Ca Ski RT_A with one gene insert had reduced migration rate, decreased clonogenic activity in vitro, and diminished capacity to form tumors in nude mice, increase in RT_A copicity/expression mitigated these effects. Altogether, expression of HIV-1 RT_A gave Ca Ski cells the plasticity required to overcome negative effects of lentiviral transduction and potentially increased their tumorigenicity.

Hepatitis C virus (HCV) is an oncogenic virus that causes chronic liver disease in more than 80% of patients. During the last decade, efficient direct acting antivirals were introduced into clinical practice. However, clearance of the virus does not reduce risk of end-stage liver diseases to the level observed in patients that have never been infected. So, investigation of HCV pathogenesis is still warranted. Virus-induced changes in cell metabolism contribute to the development of HCV-associated liver pathologies. Here we studied the impact of the virus on the metabolism of polyamines and proline as well as on the urea cycle, which plays a crucial role in liver function. It was found that HCV strongly suppresses the expression of arginase, a key enzyme of the urea cycle, leading to accumulation of arginine and upregulates proline oxidase with a concomitant decrease in proline concentrations. Addition of exogenous proline moderately suppressed viral replication. HCV upregulated transcription but suppressed protein levels of polyamine-metabolizing enzymes. This resulted in a decrease in polyamine content in infected cells. Finally, compounds targeting polyamine metabolism demonstrated pronounced antiviral activity pointing to spermine and spermidine as compounds affecting HCV replication. These data expand our understanding of HCV’s imprint on cell metabolism.