Gene Expression Comparison between Alcohol-Exposed versus Not Exposed Pancreatic Ductal Adenocarcinoma Patients Reveals a Peculiar TGFß-Related Phenotype: An Exploratory Analysis.

Background: Over the past few decades, there has been much debate and research into the link between alcohol consumption and the development and progression of pancreatic ductal adenocarcinoma (PDAC). Objectives: To contribute to the ongoing discussion and gain further insights into this topic, our study analysed the gene expression differences in PDAC patients based on their alcohol consumption history. Methods: To this end, we interrogated a large publicly available dataset. We next validated our findings in vitro. Results: Our findings revealed that patients with a history of alcohol consumption showed significant enrichment in the TGFß-pathway: a signaling pathway implicated in cancer development and tumor progression. Specifically, our bioinformatic dissection of gene expression differences in 171 patients with PDAC showed that those who had consumed alcohol had higher levels of TGFß-related genes. Moreover, we validated the role of the TGFß pathway as one of the molecular drivers in producing massive stroma, a hallmark feature of PDAC, in patients with a history of alcohol consumption. This suggests that inhibition of the TGFß pathway could serve as a novel therapeutic target for PDAC patients with a history of alcohol consumption and lead to increased sensitivity to chemotherapy. Our study provides valuable insights into the molecular mechanisms underlying the link between alcohol consumption and PDAC progression. Conclusions: Our findings highlight the potential significance of the TGFß pathway as a therapeutic target. The development of TGFß-inhibitors may pave the way for developing more effective treatment strategies for PDAC patients with a history of alcohol consumption.

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 identification 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 identified 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 significantly correlated with poorer progression-free survival (PFS) and overall survival (OS). Significant 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 confirmed 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 trafficking and tumor spheroids killing. CONCLUSION: Our study identified 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.

BRAFV600E;K601Q metastatic melanoma patient-derived organoids and docking analysis to predict the response to targeted therapy.

The V600E mutation in BRAF is associated with increased phosphorylation of Erk1/2 and high sensitivity to BRAFi/MEKi combination in metastatic melanoma. In very few patients, a tandem mutation in BRAF, V600 and K601, causes a different response to BRAFi/MEKi combination. BRAFV600E;K601Q patient-derived organoids (PDOs) were generated to investigate targeted therapy efficacy and docking analysis was used to assess BRAFV600E;K601Q interactions with Vemurafenib. PDOs were not sensitive to Vemurafenib and Cobimetinib given alone and sensitive to their combination, although not as responsive as BRAFV600E PDOs. The docking analysis justified such a result showing that the tandem mutation in BRAF reduced the affinity for Vemurafenib. Tumor analysis showed that BRAFV600E;K601Q displayed both increased phosphorylation of Erk1/2 at cytoplasmic level and activation of Notch resistance signaling. This prompted us to inhibit Notch signaling with Nirogacestat, achieving a greater antitumor response and providing PDOs-based evaluation of treatment efficacy in such rare metastatic melanoma.

Long Non-Coding RNA Landscape in Prostate Cancer Molecular Subtypes: A Feature Selection Approach.

Prostate cancer is one of the most common malignancies in men. It is characterized by a high molecular genomic heterogeneity and, thus, molecular subtypes, that, to date, have not been used in clinical practice. In the present paper, we aimed to better stratify prostate cancer patients through the selection of robust long non-coding RNAs. To fulfill the purpose of the study, a bioinformatic approach focused on feature selection applied to a TCGA dataset was used. In such a way, LINC00668 and long non-coding(lnc)-SAYSD1-1, able to discriminate ERG/not-ERG subtypes, were demonstrated to be positive prognostic biomarkers in ERG-positive patients. Furthermore, we performed a comparison between mutated prostate cancer, identified as "classified", and a group of patients with no peculiar genomic alteration, named "not-classified". Moreover, LINC00920 lncRNA overexpression has been linked to a better outcome of the hormone regimen. Through the feature selection approach, it was found that the overexpression of lnc-ZMAT3-3 is related to low-grade patients, and three lncRNAs: lnc-SNX10-87, lnc-AP1S2-2, and ADPGK-AS1 showed, through a co-expression analysis, significant correlation values with potentially druggable pathways. In conclusion, the data mining of publicly available data and robust bioinformatic analyses are able to explore the unknown biology of malignancies.

Crizotinib sensitizes the erlotinib resistant HCC827GR5 cell line by influencing lysosomal function.

In non-small cell lung cancer, sensitizing mutations in epidermal growth factor receptor (EGFR) or cMET amplification serve as good biomarkers for targeted therapies against EGFR or cMET, respectively. Here we aimed to determine how this different genetic background would affect the interaction between the EGFR-inhibitor erlotinib and the cMET-inhibitor crizotinib. To unravel the mechanism of synergy we investigated the effect of the drugs on various parameters, including cell cycle arrest, migration, protein phosphorylation, kinase activity, the expression of drug efflux pumps, intracellular drug concentrations, and live-cell microscopy. We observed additive effects in EBC-1, H1975, and HCC827, and a strong synergism in the HCC827GR5 cell line. This cell line is a clone of the HCC827 cells that harbor an EGFR exon 19 deletion and has been made resistant to the EGFR-inhibitor gefitinib, resulting in cMET amplification. Remarkably, the intracellular concentration of crizotinib was significantly higher in HCC827GR5 compared to the parental HCC827 cell line. Furthermore, live-cell microscopy with a pH-sensitive probe showed a differential reaction of the pH in the cytoplasm and the lysosomes after drug treatment in the HCC827GR5 in comparison with the HCC827 cells. This change in pH could influence the process of lysosomal sequestration of drugs. These results led us to the conclusion that lysosomal sequestration is involved in the strong synergistic reaction of the HCC827GR5 cell line to crizotinib-erlotinib combination. This finding warrants future clinical studies to evaluate whether genetic background and lysosomal sequestration could guide tailored therapeutic interventions.

Tomatine Displays Antitumor Potential in In Vitro Models of Metastatic Melanoma.

There is a growing interest in the cytotoxic effects of bioactive glycoalkaloids, such as α-tomatine on tumor cells. Here, for the first time, we determine the antitumor potential of tomatine, a mixture of α-tomatine and dehydrotomatine, in metastatic melanoma (MM) cell lines harboring different BRAF and MC1R variants. We performed cytotoxicity experiments and annexin-V/propidium iodide staining to assess the apoptotic/necrotic status of the cells. ER stress and autophagy markers were revealed by Western Blot, whereas antiangiogenic and vascular-disrupting effects were evaluated through a capillary tube formation assay on matrigel and by ELISA kit for VEGF release determination. Cell invasion was determined by a Boyden chamber matrigel assay. Tomatine reduced 50% of cell viability and induced a concentration-dependent increase of apoptotic cells in the range of 0.5-1 µM in terms of α-tomatine. The extent of apoptosis was more than two-fold higher in V600BRAF-D184H/D184H MC1R cells than in BRAF wild-type cells and V600BRAF-MC1R wild-type cell lines. Additionally, tomatine increased the LC3I/II autophagy marker, p-eIF2α, and p-Erk1/2 levels in BRAF wild-type cells. Notably, tomatine strongly reduced cell invasion and melanoma-dependent angiogenesis by reducing VEGF release and tumor-stimulating effects on capillary tube formation. Collectively, our findings support tomatine as a potential antitumor agent in MM.

Hydroxy-Propil-ß-Cyclodextrin Inclusion Complexes of two Biphenylnicotinamide Derivatives: Formulation and Anti-Proliferative Activity Evaluation in Pancreatic Cancer Cell Models.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with poor outcomes largely due to its unique microenvironment, which is responsible for the low response to drugs and drug-resistance phenomena. This clinical need led us to explore new therapeutic approaches for systemic PDAC treatment by the utilization of two newly synthesized biphenylnicotinamide derivatives, PTA73 and PTA34, with remarkable antitumor activity in an in vitro PDAC model. Given their poor water solubility, inclusion complexes of PTA34 and PTA73 in Hydroxy-Propil-ß-Cyclodextrin (HP-ß-CD) were prepared in solution and at the solid state. Complexation studies demonstrated that HP-ß-CD is able to form stable host-guest inclusion complexes with PTA34 and PTA73, characterized by a 1:1 apparent formation constant of 503.9 M-1 and 369.2 M-1, respectively (also demonstrated by the Job plot), and by an increase in aqueous solubility of about 150 times (from 1.95 µg/mL to 292.5 µg/mL) and 106 times (from 7.16 µg/mL to 762.5 µg/mL), in the presence of 45% w/v of HP-ß-CD, respectively. In vitro studies confirmed the high antitumor activity of the complexed PTA34 and PTA73 towards PDAC cells, the strong G2/M phase arrest followed by induction of apoptosis, and thus their eligibility for PDAC therapy.

New insight into the role of metabolic reprogramming in melanoma cells harboring BRAF mutations.

This study explores the V600BRAF-MITF-PGC-1α axis and compares metabolic and functional changes occurring in primary and metastatic V600BRAF melanoma cell lines. V600BRAF mutations in homo/heterozygosis were found to be correlated to high levels of pERK, to downregulate PGC-1α/ß, MITF and tyrosinase activity, resulting in a reduced melanin synthesis as compared to BRAFwt melanoma cells. In this scenario, V600BRAF switches on a metabolic reprogramming in melanoma, leading to a decreased OXPHOS activity and increased glycolytic ATP, lactate, HIF-1α and MCT4 levels. Furthermore, the induction of autophagy and the presence of ER stress markers in V600BRAF metastatic melanoma cells suggest that metabolic adaptations of these cells occur as compensatory survival mechanisms. For the first time, we underline the role of peIF2α as an important marker of metastatic behaviour in melanoma. Our results suggest the hypothesis that inhibition of the glycolytic pathway, inactivation of peIF2α and a reduction of basal autophagy could be suitable targets for novel combination therapies in a specific subgroup of metastatic melanoma.

Hepatic stellate cells induce hepatocellular carcinoma cell resistance to sorafenib through the laminin-332/α3 integrin axis recovery of focal adhesion kinase ubiquitination.

In patients with hepatocellular carcinoma (HCC) receiving sorafenib, drug resistance is common. HCC develops in a microenvironment enriched with extracellular matrix proteins including laminin (Ln)-332, produced by hepatic stellate cells (HSCs). Ln-332 is the ligand of α3ß1 and α6ß4 integrins, differently expressed on the HCC cell surface, that deliver intracellular pathways. The aim of this study was to investigate the effect of Ln-332 on sorafenib's effectiveness. HCC cells were challenged with sorafenib in the presence of Ln-332 and of HSC conditioned medium (CM). Sorafenib impaired HCC cell proliferation and induced apoptosis. HSC-CM or Ln-332 inhibited sorafenib's effectiveness in HCC cells expressing both α3ß1 and α6ß4. Inhibiting α3 but not α6 integrin subunit using blocking antibodies or small interfering RNA abrogated the protection induced by Ln-332 and HSC-CM. Hep3B cells expressing α6ß4 but lacking the α3 integrin were insensitive to Ln-332 and HSC-CM protective effects. Hep3B α3-positive, but not wild-type and scramble transfected, cells acquired protection by sorafenib when plated on Ln-332-CM or HSCs. Sorafenib dephosphorylated focal adhesion kinase (FAK) and extracellular signal-regulated kinases 1/2, whereas Ln-332 and HSC-CM partially restored the pathways. Silencing FAK, but not extracellular signal-regulated kinases 1/2, abrogated the protection induced by Ln-332 and HSC-CM, suggesting a specific role for FAK. Sorafenib down-regulated total FAK, inducing its proteasomal degradation, while Ln-332 and HSC-CM promoted the escape of FAK from ubiquitination, probably inducing a preferential membrane localization. CONCLUSION: This study unveils a novel mechanism of sorafenib resistance depending on the α3ß1/Ln-332 axis and requiring FAK ubiquitination, providing new insights into personalizing therapy for patients with HCC. (Hepatology 2016;64:2103-2117).

Synthesis, Characterization, and Cytotoxicity of the First Oxaliplatin Pt(IV) Derivative Having a TSPO Ligand in the Axial Position.

The first Pt(IV) derivative of oxaliplatin carrying a ligand for TSPO (the 18-kDa mitochondrial translocator protein) has been developed. The expression of the translocator protein in the brain and liver of healthy humans is usually low, oppositely to steroid-synthesizing and rapidly proliferating tissues, where TSPO is much more abundant. The novel Pt(IV) complex, cis,trans,cis-[Pt(ethanedioato)Cl{2-(2-(4-(6,8-dichloro-3-(2-(dipropylamino)-2-oxoethyl)imidazo[1,2-a]pyridin-2-yl)phenoxy)acetate)-ethanolato}(1R,2R-DACH)] (DACH = diaminocyclohexane), has been fully characterized by spectroscopic and spectrometric techniques and tested in vitro against human MCF7 breast carcinoma, U87 glioblastoma, and LoVo colon adenocarcinoma cell lines. In addition, affinity for TSPO (IC50 = 18.64 nM), cellular uptake (ca. 2 times greater than that of oxaliplatin in LoVo cancer cells, after 24 h treatment), and perturbation of cell cycle progression were investigated. Although the new compound was less active than oxaliplatin and did not exploit a synergistic proapoptotic effect due to the presence of the TSPO ligand, it appears to be promising in a receptor-mediated drug targeting context towards TSPO-overexpressing tumors, in particular colorectal cancer (IC50 = 2.31 µM after 72 h treatment).

Aurora kinase B inhibition reduces the proliferation of metastatic melanoma cells and enhances the response to chemotherapy.

BACKGROUND: The poor response to chemotherapy and the brief response to vemurafenib in metastatic melanoma patients, make the identification of new therapeutic approaches an urgent need. Interestingly the increased expression and activity of the Aurora kinase B during melanoma progression suggests it as a promising therapeutic target. METHODS: The efficacy of the Aurora B kinase inhibitor barasertib-HQPA was evaluated in BRAF mutated cells, sensitive and made resistant to vemurafenib after chronic exposure to the drug, and in BRAF wild type cells. The drug effectiveness has been evaluated as cell growth inhibition, cell cycle progression and cell migration. In addition, cellular effectors of drug resistance and response were investigated. RESULTS: The characterization of the effectors responsible for the resistance to vemurafenib evidenced the increased expression of MITF or the activation of Erk1/2 and p-38 kinases in the newly established cell lines with a phenotype resistant to vemurafenib. The sensitivity of cells to barasertib-HQPA was irrespective of BRAF mutational status. Barasertib-HQPA induced the mitotic catastrophe, ultimately causing apoptosis and necrosis of cells, inhibited cell migration and strongly affected the glycolytic metabolism of cells inducing the release of lactate. In association i) with vemurafenib the gain in effectiveness was found only in BRAF(V600K) cells while ii) with nab-paclitaxel, the combination was more effective than each drug alone in all cells. CONCLUSIONS: These findings suggest barasertib as a new therapeutic agent and as enhancer of chemotherapy in metastatic melanoma treatment.

Irradiation-induced angiosarcoma and anti-angiogenic therapy: a therapeutic hope?

Angiosarcomas are rare soft-tissue sarcomas of endothelial cell origin. They can be sporadic or caused by therapeutic radiation, hence secondary breast angiosarcomas are an important subgroup of patients. Assessing the molecular biology of angiosarcomas and identify specific targets for treatment is challenging. There is currently great interest in the role of angiogenesis and of angiogenic factors associated with tumor pathogenesis and as targets for treatment of angiosarcomas. A primary cell line derived from a skin fragment of a irradiation-induced angiosarcoma patient was obtained and utilized to evaluate cell biomarkers CD31, CD34, HIF-1 alpha and VEGFRs expression by immunocytochemistry and immunofluorescence, drugs cytotoxicity by cell counting and VEGF release by ELISA immunoassay. In addition to previous biomarkers, FVIII and VEGF were also evaluated on tumor specimens by immunohistochemistry to further confirm the diagnosis. We targeted the VEGF-VEGFR-2 axis of tumor angiogenesis with two different class of vascular targeted drugs; caprelsa, the VEGFR-2/EGFR/RET inhibitor and bevacizumab the anti-VEGF monoclonal antibody. We found the same biomarkers expression either in tumor specimens and in the cell line derived from tumor. In vitro experiments demonstrated that angiogenesis plays a pivotal role in the progression of this tumor as cells displayed high level of VEGFR-2, HIF-1 alpha strongly accumulated into the nucleus and the pro-angiogenic factor VEGF was released by cells in culture medium. The evaluation of caprelsa and bevacizumab cytotoxicity demonstrated that both drugs were effective in inhibiting tumor proliferation. Due to these results, we started to treat the patient with pazopanib, which was the unique tyrosine kinase inhibitor available in Italy through a compassionate supply program, obtaining a long lasting partial response. Our data suggest that the study of the primary cell line could help physicians in choosing a therapeutic approach for patient that almost in vitro shows chances of success and that the anti-angiogenetic agents are a reliable therapeutic opportunity for angiosarcomas patients.

Small-Cell Lung Cancer: Is Liquid Biopsy a New Tool Able to Predict the Efficacy of Immunotherapy?

Small-cell lung cancer (SCLC) cases represent approximately 15% of all lung cancer cases, remaining a recalcitrant malignancy with poor survival and few treatment options. In the last few years, the addition of immunotherapy to chemotherapy improved clinical outcomes compared to chemotherapy alone, resulting in the current standard of care for SCLC. However, the advantage of immunotherapy only applies to a few SCLC patients, and predictive biomarkers selection are lacking for SCLC. In particular, due to some features of SCLC, such as high heterogeneity, elevated cell plasticity, and low-quality tissue samples, SCLC biopsies cannot be used as biomarkers. Therefore, the characterization of the tumor and, subsequently, the selection of an appropriate therapeutic combination may benefit greatly from liquid biopsy. Soluble factors, circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and extracellular vesicles (EVs) are now useful tools in the characterization of SCLC. This review summarizes the most recent data on biomarkers detectable with liquid biopsy, emphasizing their role in supporting tumor detection and their potential role in SCLC treatment choice.

Microfluidic development and biological evaluation of targeted therapy-loaded biomimetic nano system to improve the metastatic melanoma treatment.

Optimizing current therapies is among next steps in metastatic melanoma (MM) treatment landscape. The innovation of this study is the design of production process by microfluidics of cell membrane (CM)-modified nanoparticles (NPs), as an emerging biomimetic platform that allows for reduced immune clearance, long blood circulation time and improved specific tumor targeting. To achieve melanoma selectivity, direct membrane fusion between synthetic liposomes and CMs extracted from MM cell line was performed by microfluidic sonication approach, then the hybrid liposomes were loaded with cobimetinib (Cob) or lenvatinib (Lenva) targeting agents and challenged against MM cell lines and liver cancer cell line to evaluate homotypic targeting and antitumor efficacy. Characterization studies demonstrated the effective fusion of CM with liposome and the high encapsulation efficiency of both drugs, showing the proficiency of microfluidic-based production. By studying the targeting of melanoma cells by hybrid liposomes versus liposomes, we found that both NPs entered cells through endocytosis, whereas the former showed higher selectivity for MM cells from which CM was extracted, with 8-fold higher cellular uptake than liposomes. Hybrid liposome formulation of Cob and Lenva reduced melanoma cells viability to a greater extent than liposomes and free drug and, notably, showed negligible toxicity as demonstrated by bona fide haemolysis test. The CM-modified NPs presented here have the potential to broaden the choice of therapeutic options in MM treatment.

Cervical cancer benefits from trabectedin combination with the ß-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 ß-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 ß-adrenergic receptor activation in both ovarian and cervical cancer models.

Circulating extracellular vesicles are monitoring biomarkers of anti-PD1 response and enhancer of tumor progression and immunosuppression in metastatic melanoma.

BACKGROUND: Clinical drawback in checkpoint inhibitors immunotherapy (ICI) of metastatic melanoma (MM) is monitoring clinical benefit. Soluble forms of PD1(sPD1) and PD-L1(sPD-L1) and extracellular vesicles (EVs) expressing PD1 and PD-L1 have recently emerged as predictive biomarkers of response. As factors released in the blood, EVs and soluble forms could be relevant in monitoring treatment efficacy and adaptive resistance to ICI. METHODS: We used pre-therapy plasma samples of 110 MM patients and longitudinal samples of 46 patients. Elisa assay and flow cytometry (FCM) were used to measure sPD-L1 and sPD1 concentrations and the percentage of PD1+ EVs and PD-L1+ EVs, released from tumor and immune cells in patients subsets. Transwell assays were conducted to investigate the impact of EVs of each patient subset on MM cells invasion and interaction between tumor cells and macrophages or dendritic cells. Viability assays were performed to assess EVs effect on MM cells and organoids sensitivity to anti-PD1. FCM was used to investigate immunosuppressive markers in EVs and immune cells. RESULTS: The concentrations of sPD1 and sPD-L1 in pre-treatment and longitudinal samples did not correlate with anti-PD1 response, instead only tumor-derived PD1+ EVs decreased in long responders while increased during disease progression in responders. Notably, we observed reduction of T cell derived EVs expressing LAG3+ and PD1+ in long responders and their increase in responders experiencing progression. By investigating the impact of EVs on disease progression, we found that those isolated from non-responders and from patients with progression disease accelerated tumor cells invasiveness and migration towards macrophages, while EVs of long responders reduced the metastatic potential of MM cells and neo-angiogenesis. Additionally, the EVs of non-responders and of progression disease patients subset reduced the sensitivity of MM cells and organoids of responder to anti-PD1 and the recruitment of dendritic cells, while the EVs of progression disease subset skewed macrophages to express higher level of PDL-1. CONCLUSION: Collectively, we suggest that the detection of tumor-derived PD1 + EVs may represent a useful tool for monitoring the response to anti-PD1 and a role for EVs shed by tumor and immune cells in promoting tumor progression and immune dysfunction.

The ERRα-VDR axis promotes calcitriol degradation and estrogen signaling in breast cancer cells, while VDR-CYP24A1-ERRα overexpression correlates with poor prognosis in patients with basal-like breast cancer.

Vitamin D is used to reduce cancer risk and improve the outcome of cancer patients, but the vitamin D receptor (VDR; also known as the calcitriol receptor) pathway needs to be functionally intact to ensure the biological effects of circulating calcitriol, the active form of vitamin D. Besides estrogen receptor alpha (ERα), estrogen-related receptor alpha (ERRα) has also been shown to interfere with the VDR pathway, but its role in the antitumor and transactivation activity of calcitriol is completely unknown in breast cancer (BC). We observed that ERRα functionally supported the proliferation of BC cell lines and acted as a calcitriol-induced regulator of VDR. As such, ERRα deregulated the calcitriol-VDR transcription by enhancing the expression of CYP24A1 as well as of both ERα and aromatase (CYP19A1) in calcitriol-treated cells. ERRα knockdown limited the effect of calcitriol by reducing calcitriol-induced G0/G1 phase cell cycle arrest and by affecting the expression of cyclin D1 and p21/Waf. The interactome analysis suggested that Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-α (PGC-1α) and Proline-, glutamic acid-, and leucine-rich protein 1 (PELP1) are key players in the genomic actions of the calcitriol-VDR-ERRα axis. Evaluation of patient outcomes in The Cancer Genome Atlas (TCGA) dataset showed the translational significance of the biological effects of the VDR-ERRα axis, highlighting that VDR, CYP24A1, and ERRα overexpression correlates with poor prognosis in basal-like BC.

Behind the Scene: Exploiting MC1R in Skin Cancer Risk and Prevention.

Melanoma and non-melanoma skin cancers (NMSCs) are the most frequent cancers of the skin in white populations. An increased risk in the development of skin cancers has been associated with the combination of several environmental factors (i.e., ultraviolet exposure) and genetic background, including melanocortin-1 receptor (MC1R) status. In the last few years, advances in the diagnosis of skin cancers provided a great impact on clinical practice. Despite these advances, NMSCs are still the most common malignancy in humans and melanoma still shows a rising incidence and a poor prognosis when diagnosed at an advanced stage. Efforts are required to underlie the genetic and clinical heterogeneity of melanoma and NMSCs, leading to an optimization of the management of affected patients. The clinical implications of the impact of germline MC1R variants in melanoma and NMSCs' risk, together with the additional risk conferred by somatic mutations in other peculiar genes, as well as the role of MC1R screening in skin cancers' prevention will be addressed in the current review.

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.

uPAR+ extracellular vesicles: a robust biomarker of resistance to checkpoint inhibitor immunotherapy in metastatic melanoma patients.

BACKGROUND: Emerging evidence has highlighted the importance of extracellular vesicle (EV)-based biomarkers of resistance to immunotherapy with checkpoint inhibitors in metastatic melanoma. Considering the tumor-promoting implications of urokinase-type plasminogen activator receptor (uPAR) signaling, this study aimed to assess uPAR expression in the plasma-derived EVs of patients with metastatic melanoma to determine its potential correlation with clinical outcomes. METHODS: Blood samples from 71 patients with metastatic melanoma were collected before initiating immunotherapy. Tumor-derived and immune cell-derived EVs were isolated and analyzed to assess the relative percentage of uPAR+ EVs. The associations between uPAR and clinical outcomes, sex, BRAF status, baseline lactate dehydrogenase levels and number of metastatic sites were assessed. RESULTS: Responders had a significantly lower percentage of tumor-derived, dendritic cell (DC)-derived and CD8+ T cell-derived uPAR +EVs at baseline than non-responders. The Kaplan-Meier survival curves for the uPAR+EV quartiles indicated that higher levels of melanoma-derived uPAR+ EVs were strongly correlated with poorer progression-free survival (p<0.0001) and overall survival (p<0.0001). We also found a statistically significant correlation between lower levels of uPAR+ EVs from both CD8+ T cells and DCs and better survival. CONCLUSIONS: Our results indicate that higher levels of tumor-derived, DC-derived and CD8+ T cell-derived uPAR+ EVs in non-responders may represent a new biomarker of innate resistance to immunotherapy with checkpoint inhibitors. Moreover, uPAR+ EVs represent a new potential target for future therapeutic approaches.