Gasdermin C as a potential prognostic biomarker and its correlation with immune infiltration in pancreatic ductal adenocarcinoma.

e16256 Background: Although pyroptosis is critical for macrophages against pathogen infection, its role in cancer cells remains elusive. GSDMC is a pyroptosis executioner newly identified in cancer cells and have been shown to facilitate inflammatory tumor death. However, the expression of GSDMC in Pancreatic Ductal Adenocarcinoma (PDAC), its prognostic significance and possible impact on reshaping tumor immune microenviroment in PDAC is still unknown. Methods: We investigated the expression level of GSDMC using TNM plotter with TCGA and GTEx databases, the prognostic value of GSDMC in PDAC using Kaplan-Meier plotter with TCGA, GTEx and TCGA databases. The correlations between GSDMC and immune infiltration in PDAC were calculated using TIMER2.0 and TIDE with TCGA database. We further validated the prognostic value of GSDMC with immunohistochemistry(IHC) staining on a tissue microarray of 172 cases of PDAC patients receiving treatment in our institution. Correlations between expression of GSDMC and tumor infiltration lymphacytes(TILs) cells were also analyzed on tissue samples of those 172 PDAC patients. Results: TNM plotter analysis shows that the expression of GSDMC in PDAC tumor tissue is 10.49 folds higher than it is in pancreatic normal tissues (p = 8.86*e-56). Results from Kaplan-Meier plotter analysis shows high expression of GSDMC is significantly correlated with poorer overall survival(OS), HR = 1.8(1.19−2.71) logrank P = 0.004 and shorter relapse free survival (RFS), HR = 4.6(1.94−10.88), Logrank P = 0.00014 in PDAC. Analysis with TIMER2.0 and TIDE platform shows that expression of GSDMC is positively correlated with immunosuppressive cells, Cancer Associated Fiberblast (CAF) and Meyloid Derived Tumor Suprresso Cells(MDTSC). IHC staining analysis results is also consistent with aformentioned bioinformatic analysis, showing that high GSDMC expression correlated with shorter OS and reduced Tils infiltration. Conclusions: Our findings suggest that high expression of GSDMC is related to poor prognosis and compromised immune cell infiltration in PDAC. GSDMC holds promise for serving as a valuable prognostic marker and therapeutic target in PDAC.