Search

Among the mechanisms leading to progression to Adult T-cell Leukaemia/Lymphoma in Human T-cell Leukaemia Virus type 1 (HTLV-1)-infected subjects, the contribution of stromal components remains poorly understood. To dissect the role of fibroblasts in HTLV-1-mediated lymphomagenesis, transcriptome studies, cytofluorimetric and qRT-PCR analyses of surface and intracellular markers linked to plasticity and stemness in coculture, and in vivo experiments were performed. A transcriptomic comparison between a more lymphomagenic (C91/III) and the parental (C91/PL) cell line evidenced hyperactivation of the PI3K/Akt pathway, confirmed by phospho-ELISA and 2-DE and WB analyses. C91/III cells also showed higher expression of mesenchymal and stemness genes. Short-term coculture with human foreskin fibroblasts (HFF) induced these features in C91/PL cells, and significantly increased not only the cancer stem cells (CSCs)-supporting CD10+GPR77+ HFF subpopulation, but also the percentage of ALDH1bright C91/PL cells. A non-cytotoxic acetylsalicylic acid treatment decreased HFF-induced ALDH1bright C91/PL cells, downregulated mesenchymal and stemness genes in cocultured cells, and delayed lymphoma growth in immunosuppressed mice, thus hindering the supportive activity of HFF on CSCs. These data suggest that crosstalk with HFF significantly intensifies the aggressiveness and plasticity of C91/PL cells, leading to the enrichment in lymphoma-initiating cells. Additional research is needed to better characterize these preliminary findings.

The intraductal oncocytic papillary neoplasm (IOPN) of the pancreas has been recognized by WHO classification as a unique intraductal papillary mucinous neoplasm (IPMN) category. IOPN is composed of oxyphil cells, usually expressing MUC5AC, MUC6, and Hep Par-1, and harboring PRKACA/B fusion genes as their genetic hallmark. Although IOPNs are associated with an infiltrative adenocarcinoma in up to 30% of cases, the survival rate after surgical resection approaches 100%. This highlights the importance of the correct IOPN diagnosis, above all in cases with an associated invasive component. In this study, the immunohistochemical expression of CD117 was investigated in 111 IPMNs, including 17 oncocytic, 45 gastric, 20 pancreatico-biliary, and 29 intestinal IPMNs. We also tested the expression of MUC5AC, MUC6, and Hep Par-1 in the IOPN cohort. CD117 positivity was significantly more frequent in IOPNs compared to the other IPMN subtypes (p &lt, 0.0001). Furthermore, within IOPN, a lower or absent CD117, MUC5AC, MUC6, and Hep Par-1 expression tended to be associated with the presence of an infiltrative component. Our findings shed light into the biology of these complex lesions, which are confirmed to be a distinctive IPMN subtype, notably, CD117 emerged as a potential, additional tool in the differential diagnosis of IPMNs.

To date, pancreatic cancer is still one of the most lethal cancers in the world, mainly due to the lack of early diagnosis and personalized treatment strategies. In this context, the possibility and the opportunity of identifying genetic and molecular biomarkers are crucial to improve the feasibility of precision medicine. In 2019, the World Health Organization classified pancreatic ductal adenocarcinoma cancer (the most common pancreatic tumor type) into eight variants, according to specific histomorphological features. They are: colloid carcinoma, medullary carcinoma, adenosquamous carcinoma, undifferentiated carcinoma, including also rhabdoid carcinoma, undifferentiated carcinoma with osteoclast-like giant cells, hepatoid carcinoma, and signet-ring/poorly cohesive cells carcinoma. Interestingly, despite the very low incidence of these variants, innovative high throughput genomic/transcriptomic techniques allowed the investigation of both somatic and germline mutations in each specific variant, paving the way for their possible classification according also to specific alterations, along with the canonical mutations of pancreatic cancer (KRAS, TP53, CDKN2A, SMAD4). In this review, we aim to report the current evidence about genetic/molecular profiles of pancreatic cancer variants, highlighting their role in therapeutic and clinical impact.