RESUMO
Introduction: Malignant pleural mesothelioma (MPM) is a rare and universally lethal malignancy with limited treatment options. Immunotherapy with immune checkpoint inhibitors (ICIs) has recently been approved for unresectable MPM, but response to ICIs is heterogeneous, and reliable biomarkers for prospective selection of appropriate subpopulations likely to benefit from ICIs remain elusive. Methods: We performed multiscale integrative analyses of published primary tumor data set from The Cancer Genome Atlas (TCGA) and the French cohort E-MTAB-1719 to unravel the tumor immune microenvironment of MPM deficient in BAP1, one of the most frequently mutated tumor suppressor genes (TSGs) in the disease. The molecular profiling results were validated in independent cohorts of patients with MPM using immunohistochemistry and multiplex immunohistochemistry. Results: We revealed that BAP1 deficiency enriches immune-associated pathways in MPM, leading to increased mRNA signatures of interferon alfa/gamma response, activating dendritic cells, immune checkpoint receptors, and T-cell inflammation. This finding was confirmed in independent patient cohorts, where MPM tumors with low BAP1 levels are associated with an inflammatory tumor immune microenvironment characterized by increased exhausted precursor T-cells and macrophages but decreased myeloid-derived suppressor cells (MDSCs). In addition, BAP1low MPM cells are in close proximity to T cells and therefore can potentially be targeted with ICIs. Finally, we revealed that BAP1-proficient MPM is associated with a hyperactive mitogen-activated protein kinase (MAPK) pathway and may benefit from treatment with MEK inhibitors (MEKis). Conclusion: Our results suggest that BAP1 plays an immunomodulatory role in MPM and that BAP1-deficient MPM may benefit from immunotherapy, which merits further clinical investigation.
RESUMO
Background: Pulmonary carcinoids (PCs) are rare neuroendocrine lung tumors which may recur, thus worsening their otherwise favorable overall prognosis. Aiming to identify patients at risk for recurrence, we examined parameters affecting disease-free survival (DFS). Methods: A retrospective single-center analysis of 82 consecutive patients undergoing curative intent resection for primary PC tumors between 2010 and 2019 was carried out. Kaplan-Meier method was utilized for survival analysis. Independent prognostic factors were determined using multivariable Cox and logistic regression. Results: During the observation period 82 patients, 48 females (58.5%) and 34 males (41.5%) were operated, representing 84 cases of PCs, 56 typical (TCs) (66.7%) and 28 atypical (ACs) (33.3%) carcinoids. Five-year overall survival was 87.5% and 84.7%, 5-year DFS 97.5% and 74.9% (P=0.012) for TCs and ACs, respectively. Recurrences occurred in one patient (1.8%) with TCs and five patients (17.9%) with ACs (P=0.014). Using multivariable Cox regression, tumor size (cm) remained as an independent prognostic factor for reduced DFS (P=0.018). In logistic regression, nodal involvement (P=0.043) and tumor size (cm) (P=0.023) were independently associated with higher risk of recurrence. Age, sex, smoking, location, and Ki-67 index were not independently associated with recurrence or DFS. Conclusions: Recurrence in PCs after complete resection is relatively rare. However, DFS is reduced in ACs compared to TCs. Tumor size (cm) and nodal involvement appear as the most important prognostic factors associated with recurrence in PCs, independent of histologic type.