The role of non-coding RNAs as prognostic factor, predictor of drug response or resistance and pharmacological targets, in the cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (CSCC) is the most common keratinocyte-derived skin cancer in the Caucasian population. Exposure to UV radiations (UVRs) represents the main risk carcinogenesis, causing a considerable accumulation of DNA damage in epidermal keratinocytes with an uncontrolled hyperproliferation and tumor development. The limited and rarely durable response of CSCC to the current therapeutic options has led researchers to look for new therapeutic strategies. Recently, the multi-omics approaches have contributed to the identification and prediction ofthe key role of non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), circularRNAs (circRNAs) and long non-coding RNAs (lncRNAs) in the regulation of several cellular processes in different tumor types, including CSCC. ncRNAs can modulate transcriptional and post-transcriptional events by interacting either with each other or with DNAand proteins, such as transcription factors and RNA-binding proteins.In this review, the implication of ncRNAs in tumorigenesis and their potential role as diagnostic biomarkers and therapeutic targets in human CSCC are reported

Cytochrome c is released from mitochondria in a reactive oxygen species (ROS)-dependent fashion and can operate as a ROS scavenger and as a respiratory substrate in cerebellar neurons undergoing excitotoxic death

In rat cerebellar granule cells both reactive oxygen species production and release of cytochrome c take place during glutamate toxicity. This investigation was aimed (i) to ascertain whether and how these two processes are related and (ii) to gain insight into the role played by the released cytochrome c in the onset of neurotoxicity. Cytochrome c release takes place owing to the generation of reactive oxygen species both in glutamate-treated cerebellar granule cells and in sister control cultures incubated in the presence of the reactive oxygen species-generating system consisting of xanthine plus xanthine oxidase. In the early phase of neurotoxicity (30-min glutamate exposure) about 40% of the maximum (as measured at 3 h of glutamate exposure) cytochrome c release was found to occur in cerebellar granule cells from mitochondria that were essentially coupled and intact and that had a negligible production of oxygen free radicals. Contrarily, mitochondria from cells treated with glutamate for 3 h were mostly uncoupled and produced reactive oxygen species at a high rate. The cytosolic fraction containing the released cytochrome c was able to transfer electrons from superoxide anion to molecular oxygen via the respiratory chain and was found to partially prevent glutamate toxicity when added externally to cerebellar neurons undergoing necrosis. In the light of these findings, we propose that in the early phase of neurotoxicity, cytochrome c release can be part of a cellular and mitochondrial defense mechanism against oxidative stress

Active notch protects MAPK activated melanoma cell lines from MEK inhibitor cobimetinib

The crosstalk between Notch and MAPK pathway plays a role in MEK inhibitor resistance in BRAFV600E metastatic melanoma (MM) and promotes migration in GNAQQ209L uveal melanoma (UM) cells. We determined the cytotoxicity of combinatorial inhibition of MEK and Notch by cobimetinib and γ-secretase inhibitor (GSI) nirogacestat, in BRAFV600E and BRAF wt MM and GNAQQ209L UM cells displaying different Erk1/2 and Notch activation status, with the aim to elucidate the impact of Notch signaling in the response to MEK inhibitor. Overall the combination was synergic in BRAFV600E MM and GNAQQ209L UM cells and antagonistic in BRAF wt one. Focusing on UM cells, we found that cobimetinib resulted in G0/G1 phase arrest and apoptosis induction, whereas the combination with GSI increased treatment efficacy by inducing a senescent-like state of cells and by blocking migration towards liver cancer cells. Mechanistically, this was reflected in a strong reduction of cyclin D1, in the inactivation of retinoblastoma protein and in the increase of p27KIP1 expression levels. Of note, each drug alone prevented Notch signaling activation resulting in inhibition of c-jun(Ser63) and Hes-1 expression. The combination achieved the strongest inhibition on Notch signaling and on both c-jun(Ser63) and Erk1/2 activation level. In conclusion we unveiled a coordinate action of MAPK and Notch signaling in promoting proliferation of BRAFV600E MM and GNAQQ209L UM cells. Remarkably, the simultaneous inhibition of MEK and Notch signaling highlighted a role for the second pathway in protecting cells against senescence in GNAQQ209L UM cells treated with the MEK inhibitor

Potential predictive role of chemotherapy-induced changes of soluble CD40 ligand in untreated advanced pancreatic ductal adenocarcinoma

Pancreas ductal adenocarcinoma lacks predictive biomarkers. CD40 is a member of the tumor necrosis factor superfamily. CD40-sCD40L interaction is considered to contribute to the promotion of tumor cell growth and angiogenesis. The aim of the present study was to investigate the role of serum sCD40L as a predictor in metastatic pancreatic cancer. We evaluated 27 consecutive pancreatic cancer patients treated with FOLFIRINOX (21 patients) or gemcitabine plus nab-paclitaxel combination (six patients). The sCD40L level was measured in serum by enzyme-linked immunosorbent assay at baseline, at first evaluation (all patients), and at time to progression (18 patients). The radiological response was evaluated according to the Response Evaluation Criteria in Solid Tumors, Version 1.1. The Wilcoxon signed-rank test was used to compare pre-post treatment sCD40L levels with respect to clinical response, while Pearson's correlation coefficient was used for the correlation between sCD40L and CA19.9 pre- and post-treatment. The Kruskal-Wallis test was also conducted for further comparisons. We observed a statistically significant reduction in the sCD40L level after 3 months of treatment in patients with partial response (11,718.05\ub17,097.13 pg/mL vs 4,689.42\ub15,409.96 pg/mL; P<0.01). Conversely, in patients with progressive disease, the biomarker statistically increased in the same time (9,351.51\ub17,356.91 pg/mL vs 22,282.92\ub111,629.35 pg/mL; P<0.01). This trend of sCD40L was confirmed in 18 patients at time to progression after the first evaluation. No differences were recorded within the stable disease group. Moreover, there was a positive correlation between the sCD40L and CA19.9 pre-post treatment variation percentage (Pearson's correlation coefficient =0.52; P<0.05). Our data suggest a possible predictive role of sCD40L in pancreatic cancer patients, similar to CA19.9

Microfluidic preparation and in vitro evaluation of iRGD-functionalized solid lipid nanoparticles for targeted delivery of paclitaxel to tumor cells

Solid lipid nanoparticles (SLNs) can combine the advantages of different colloidal carriers and prevent some of their disadvantages. The production of nanoparticles by means of microfluidics represents a successful platform for industrial scale-up of nanoparticle manufacture in a reproducible way. The realisation of a microfluidic technique to obtain SLNs in a continuous and reproducible manner encouraged us to create surface functionalised SLNs for targeted drug release using the same procedure. A tumor homing peptide, iRGD, owning a cryptic C-end Rule (CendR) motif is responsible for neuropilin-1 (NRP-1) binding and for triggering extravasation and tumor penetration of the peptide. In this study, the Paclitaxel loaded-SLNs produced by microfluidics were functionalized with the iRGD peptide. The SLNs proved to be stable in aqueous medium andwere characterized by a Z-average under 150 nm, a polydispersity index below 0.2, a zeta-potential between -20 and -35 mV and a drug encapsulation efficiency around 40%. Moreover, in vitro cytotoxic effects and cellular uptake have been assessed using 2D and 3D tumour models of U87 glioblastoma cell lines. Overall, these results demonstrate that the surface functionalization of SLNs with iRGD allow better cellular uptake and cytotoxicity ability.Peer reviewe

Probing Single-Cell Fermentation Fluxes and Exchange Networks via pH-Sensing Hybrid Nanofibers

The homeostatic control of their environment is an essential task of living cells. It has been hypothesized that, when microenvironmental pH inhomogeneities are induced by high cellular metabolic activity, diffusing protons act as signaling molecules, driving the establishment of exchange networks sustained by the cell-to-cell shuttling of overflow products such as lactate. Despite their fundamental role, the extent and dynamics of such networks is largely unknown due to the lack of methods in single-cell flux analysis. In this study, we provide direct experimental characterization of such exchange networks. We devise a method to quantify single-cell fermentation fluxes over time by integrating high-resolution pH microenvironment sensing via ratiometric nanofibers with constraint-based inverse modeling. We apply our method to cell cultures with mixed populations of cancer cells and fibroblasts. We find that the proton trafficking underlying bulk acidification is strongly heterogeneous, with maximal single-cell fluxes exceeding typical values by up to 3 orders of magnitude. In addition, a crossover in time from a networked phase sustained by densely connected "hubs" (corresponding to cells with high activity) to a sparse phase dominated by isolated dipolar motifs (i.e., by pairwise cell-to-cell exchanges) is uncovered, which parallels the time course of bulk acidification. Our method addresses issues ranging from the homeostatic function of proton exchange to the metabolic coupling of cells with different energetic demands, allowing for real-time noninvasive singlecell metabolic flux analysis

Circulating extracellular vesicles expressing PD1 and PD-L1 predict response and mediate resistance to checkpoint inhibitors immunotherapy in metastatic melanoma

Background: The immunotherapy with immune checkpoints inhibitors (ICI) has changed the life expectancy in metastatic melanoma (MM) patients. Nevertheless, several patients do not respond hence, the identifcation and validation of novel biomarkers of response to ICI is of crucial importance. Circulating extracellular vesicles (EVs) such as PD-L1+ EV mediate resistance to anti-PD1, instead the role of PD1+ EV is not fully understood. Methods: We isolated the circulating EVs from the plasma of an observational cohort study of 71 metastatic melanoma patients and correlated the amount of PD-L1+ EVs and PD1+ EVs with the response to ICI. The analysis was performed according to the origin of EVs from the tumor and the immune cells. Subsequently, we analysed the data in a validation cohort of 22 MM patients to assess the reliability of identifed EV-based biomarkers. Additionally we assessed the involvement of PD1+ EVs in the seizure of nivolumab and in the perturbation of immune cells-mediated killing of melanoma spheroids. Results: The level of PD-L1+ EVs released from melanoma and CD8+ T cells and that of PD1+ EVs irrespective of the cellular origin were higher in non-responders. The Kaplan-Meier curves indicated that higher levels of PD1+ EVs were signifcantly correlated with poorer progression-free survival (PFS) and overall survival (OS). Signifcant correlations were found for PD-L1+ EVs only when released from melanoma and T cells. The multivariate analysis showed that high level of PD1+ EVs, from T cells and B cells, and high level of PD-L1+ EVs from melanoma cells, are independent biomarkers of response. The reliability of PD-L1+ EVs from melanoma and PD1+ EVs from T cells in predicting PFS was confrmed in the validation cohort through the univariate Cox-hazard regression analysis. Moreover we discovered that the circulating EVs captured nivolumab and reduced the T cells trafcking and tumor spheroids killing. Conclusion: Our study identifed circulating PD1+ EVs as driver of resistance to anti-PD1, and highlighted that the analysis of single EV population by liquid biopsy is a promising tool to stratify MM patients for immunotherapy

The Interaction between Reactive Peritoneal Mesothelial Cells and Tumor Cells via Extracellular Vesicles Facilitates Colorectal Cancer Dissemination

Simple SummaryEmerging evidence has suggested that cancer-derived extracellular vesicles (EVs) have a crucial role in mediating directional metastasis to the peritoneal surface in colorectal cancer (CRC). We investigated the EV-mediated crosstalk between tumor and mesothelial cells which may drive remodeling of the premetastatic niche to allow tumor spread to the peritoneal surface. Our findings demonstrated that cancer-derived EVs triggered apoptosis and reduced mesothelial cell invasiveness and mesothelial-to-mesenchymal transition. On the other hand, mesothelial cells actively supported tumor invasion by releasing EVs, which induced upregulation of the major pro-invasive system in tumor cells. For the first time, we provide evidence of EV-driven mechanisms of CRC progression in patient-derived models, highlighting the crucial role of EVs in the reprogramming of mesothelial and tumor cells to establish the metastatic process.Advanced colorectal cancer (CRC) is highly metastatic and often results in peritoneal dissemination. The extracellular vesicles (EVs) released by cancer cells in the microenvironment are important mediators of tumor metastasis. We investigated the contribution of EV-mediated interaction between peritoneal mesothelial cells (MCs) and CRC cells in generating a pro-metastatic environment in the peritoneal cavity. Peritoneal MCs isolated from peritoneal lavage fluids displayed high CD44 expression, substantial mesothelial-to-mesenchymal transition (MMT) and released EVs that both directed tumor invasion and caused reprogramming of secretory profiles by increasing TGF-beta 1 and uPA/uPAR expression and MMP-2/9 activation in tumor cells. Notably, the EVs released by tumor cells induced apoptosis by activating caspase-3, peritoneal MC senescence, and MMT, thereby augmenting the tumor-promoting potential of these cells in the peritoneal cavity. By using pantoprazole, we reduced the biogenesis of EVs and their pro-tumor functions. In conclusion, our findings provided evidence of underlying mechanisms of CRC dissemination driven by the interaction of peritoneal MCs and tumor cells via the EVs released in the peritoneal cavity, which may have important implications for the clinical management of patients

Cervical cancer benefits from trabectedin combination with the β-blocker propranolol: in vitro and ex vivo evaluations in patient-derived organoids

Background: Cervical cancer (CC) is characterized by genomic alterations in DNA repair genes, which could favor treatment with agents causing DNA double-strand breaks (DSBs), such as trabectedin. Hence, we evaluated the capability of trabectedin to inhibit CC viability and used ovarian cancer (OC) models as a reference. Since chronic stress may promote gynecological cancer and may hinder the efficacy of therapy, we investigated the potential of targeting β-adrenergic receptors with propranolol to enhance trabectedin efficacy and change tumor immunogenicity.Methods: OC cell lines, Caov-3 and SK-OV-3, CC cell lines, HeLa and OV2008, and patient-derived organoids were used as study models. MTT and 3D cell viability assays were used for drug(s) IC50 determination. The analysis of apoptosis, JC-1 mitochondrial membrane depolarization, cell cycle, and protein expression was performed by flow cytometry. Cell target modulation analyses were carried out by gene expression, Western blotting, immunofluorescence, and immunocytochemistry.Results: Trabectedin reduced the proliferation of both CC and OC cell lines and notably of CC patient-derived organoids. Mechanistically, trabectedin caused DNA DSBs and S-phase cell cycle arrest. Despite DNA DSBs, cells failed the formation of nuclear RAD51 foci and underwent apoptosis. Under norepinephrine stimulation, propranolol enhanced trabectedin efficacy, further inducing apoptosis through the involvement of mitochondria, Erk1/2 activation, and the increase of inducible COX-2. Notably, trabectedin and propranolol affected the expression of PD1 in both CC and OC cell lines.Conclusion: Overall, our results show that CC is responsive to trabectedin and provide translational evidence that could benefit CC treatment options. Our study pointed out that combined treatment offset trabectedin resistance caused by β-adrenergic receptor activation in both ovarian and cervical cancer models