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

The evolving landscape in the management of gastric metastases from melanoma: a case series

n/

Epidermoid cyst of the coronal sulcus mimicking penile cancer: A case report

INTRODUCTION: Epidermoid cysts represent common benign tumors occurring anywhere in the body but very rarely in the penis. Only a few cases of penile localization have been reported in the literature so far, most of them being congenital and/or idiopathic, usually presenting in children as slow-growing, solitary, well-delimited cystic lesions. Here, we describe the case of a patient with a penile epidermoid cyst presenting as an ulcerated lesion of the coronal sulcus, thus mimicking penile cancer. CASE PRESENTATION: A 36-year-old Caucasian man presented with a three-month history of a rapidly growing asymptomatic ulcerated lesion in the ventral portion of the penile coronal sulcus. At surgical exploration, the area under the ulcerated lesion had a well-demarcated cystic shape; following its wide excision, an intraoperative histological examination revealed an epidermoid cyst. No recurrence had occurred at nine years of follow-up. CONCLUSIONS: Rare benign tumors of the penis, like the described epidermoid cyst, may mimic cancer. Nevertheless, penile ulcerated lesions should always be surgically explored as wide excision and intraoperative histological examination remain the only means of obtaining a precise disease definition and, consequently, administering the appropriate treatment

Angiogenesis in adenosquamous cancer of pancreas

Adenosquamous carcinoma of the pancreas (ASCP) is an uncommon variant of exocrine pancreatic malignancies, characterized by a histological admixture of adenomatous and squamous cell elements. This cancer is characterized by a poorly differentiated histology and a poorer clinical outcome compared to pancreatic ductal adenocarcinoma (PDAC). Unlike PDAC, that is characterized by a low microvascular density (MVD) and collapsed vasculature, no data are available about angiogenesis in ASPC. Immunohistochemical evaluation of MVD and trypatse-positive mast cells (MCs) were performed on a single case of ASCP compared to PDAC. Moreover, the levels of angiopoietin-1 and -2 (Ang-1, Ang-2), receptor tyrosine kinase with immunoglobulin and epidermal growth factor homology domain-2 (Tie-2), vascular endothelial growth factor A (VEGFA), hypoxia-inducible factor 1 alpha (HIF1A), miR-21-5p, miR-181a-5p, miR-122-5p, and miR-27a-3p were evaluated by real-time PCR. Higher number of tryptase-positive MCs and MVD are observed in the ASCP case compared to PDAC one. Lower levels of miR-122-5p and higher expression of VEGFA, HIF1A and Ang-2 genes were observed in ASCP. Furthermore, lower Ang-1 and Tie-2 transcript levels and higher increases of miR-21-5p, miR27a-3p and miR-181a-5p levels were found in the rarest form of pancreatic carcinoma. Our data demonstrate an important angiogenic activity in ASCP with a putative role of miR-21-5p, miR-181a-5p, miR-122-5p and miR-27a-3p in the regulation of this process

PD-L1 and Notch as novel biomarkers in Pancreatic Sarcomatoid Carcinoma: a pilot study

Background: The improved immunological understanding revealed the tumor microenvironment as an appealing driver to restore the immune response against cancer cells resulting in a paradigm shift in the oncology field. However, the complexity of the tumor milieu suggests a role of several pathways linking in immunomodulation mechanisms. Pancreatic cancer represents a model of the intricate relationship between malignant cells and their surrounding neighborhood. Research design and methods: In this study we analyzed, retrospectively, 6 cases of rare pancreatic sarcomatoid carcinoma (PSC) and evaluated the expression of PD-L1 and Notch, aiming to explore new attributes in immunophenotype. Results: PD-L1 CPS≥1% was common in PSCs (83%) with half samples expressing PD-L1 CPS≥50%. Notch1 and Notch3 expression resulted positive demonstrating a high IRS range of expression. A direct significant correlation between PD-L1 and Nocth3 overexpression (r=0.7; p=0.036) has been observed. Moreover, immunofluorescence studies revealed a co-localization of Notch3 and PD-L1 when both proteins were over-expressed within cytoplasmic or membranous compartments of the same cells. Conclusions: Our data identify a unique biological characterization of this rare pancreatic histotype. These findings provide a rationale for future studies evaluating the potential crosstalk between PD-L1/PD-1 axis and Notch pathways and prompting the development of novel therapeutics strategy

The Management of Oligoprogression in the Landscape of New Therapies for Metastatic Melanoma

Background: A limited degree of progression after a response to treatment is labelled as oligoprogression and is a hot topic of metastatic melanoma (MM) management. Rogue progressive metastases could benefit from local treatment, which could allow the continuation of ongoing systemic therapy, also known as treatment beyond progression (TBP). Methods: We retrospectively reviewed 214 selected MM patients who developed oligoprogression during treatment with v-Raf murine sarcoma viral oncogene homolog B (BRAF)/mitogen-activated-extracellular signal-regulated kinase (MEK) or programmed cell death protein 1 (PD-1) inhibitors and received a local treatment continuing TBP. We performed univariate and multivariable analyses to assess the association between therapy outcomes and a series of clinical and biological features. Results: We identified 27 (10%) oligoprogressed patients treated locally with surgery (14), radiosurgery (11), and electrochemotherapy (2). TBP included PD-1 inhibitors (13) and BRAF/MEK inhibitors (14). The median progression-free survival post oligoprogression (PFSPO) was 14 months (5-19 95% confidence interval (C.I.)). In the univariate analysis, a significantly longer PFSPO was associated with complete response (CR), Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0, neutrophils/lymphocytes ratio (N/L) <2, and progression-free survival (PFS) at oligoprogression >11 months. Nevertheless, in the multivariable analysis, only CR and N/L <2 were found to be associated with longer PFSPO. Conclusions: In selected patients, local treatments contribute to controlling oligoprogression for a long time, allowing the continuation of systemic treatment and prolongation of overall survival (OS). Increasing biological and clinical knowledge is improving the accuracy in identifying patients to apply for local ablative therapies

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

Abstract 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. Graphical Abstrac

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. BRAF(V600E;K601Q) patient-derived organoids (PDOs) were generated to investigate targeted therapy efficacy and docking analysis was used to assess BRAF(V600E;K601Q) interactions with Vemurafenib. PDOs were not sensitive to Vemurafenib and Cobimetinib given alone and sensitive to their combination, although not as responsive as BRAF v600E PDOs. The docking analysis justified such a result showing that the tandem mutation in BRAF reduced the affinity for Vemurafenib. Tumor analysis showed that BRAF(V600E;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