Investigation of\nProgrammed Death Ligand‑1\nas a New Prognostic Biomarker in Pancreatic Cancer Patients

Pancreatic cancer is one of the most\nlethal and fast-growing\ncancers\nwith a poor prognosis. Herein, we report the expression of programmed\ndeath ligand 1 (PD-L1) as a new prognostic biomarker in pancreatic\ncancer progression analysis at the clinical level. Immunohistochemistry\nwas performed on 86 clinically proven cases of pancreatic cancer tissue\nmicroarrays (TMAs) using anti-PD-L1 antibodies. Histoscore was done,\nand a variety of cutoffs were identified for analyses of the results.\nThe chi-square test and Kaplan–Meier method were used to find\nthe association between pancreatic cancer and various clinicopathological\nvariables and the overall survival of the patients. PD-L1 expression\nwas associated with histological grade and recurrence of the disease\nfor epithelial and stromal staining at 10 histoscores. In addition,\nPD-L1 expression was strongly associated with lymph node involvement\nat the stromal 20 histoscore. The tumor stage of pancreatic cancer\nhad an association with PD-L1 expression with epithelial and stromal\n20 histoscores for all comparisons. At a stromal 20 histoscore, overall\nsurvival in high-low expression of PD-L1 was 7–19 months, and\nat a nuclear/cytoplasmic 10 histoscore, it was 9–28 months\n(<i>p</i> = 0.0001), respectively. Overall, PD-L1 overexpression\nin subcellular compartments was associated with disease aggression\nphenotypes and poor patient survival. Overexpression of PD-L1 was\ndirectly linked to pancreatic cancer progression and a poor survival\nrate. Therefore, PD-L1 may be used as a prognostic biomarker in the\ndiagnosis, treatment, and management of pancreatic cancer patients.