Probes for INS

Abstract AIMS: The Protein expression of Programmed Death-Ligand 1 (PD-L1) has been recognized a poor prognostic biomarker in diffuse large B-cell lymphoma (DLBCL). We aim to detect PD-L1 DNA and mRNA status, and explore whether they contribute to protein expression and their clinicopathological correlation in DLBCL. METHODS AND RESULTS: In the study, we detected PD-L1 status in three different levels by Fluorescence in situ hybridization, RNA in situ hybridization and immunohistochemistry in 287 DLBCL samples with follow-ups, respectively. Their correlation and clinical pathological relevance was further analyzed. Our results showed that 1.7% (3/175) patients had PD-L1 amplification, 19.9% (57/287) PD-L1 mRNA high expression and 11.8% (34/287) high protein expression. Both mRNA and protein high expression of PD-L1 was significantly elevated in non-GCB than that in GCB DLBCL (P<0.05). In addition, the patients with PD-L1 mRNA or protein high expression but not DNA amplification have significantly poorer overall survival (OS) than that with PD-L1 low expression (P<0.05). Furthermore, we found that PD-L1 mRNA and protein expression are highly correlated (P=0.012), which was observed in all three samples with PD-L1 DNA amplification. CONCLUSIONS: PD-L1 DNA amplification is a rare event, PD-L1 mRNA mainly contribute to the protein high expression, and the latter two will serve as important biomarkers for predicting prognosis and selecting patients for immunotherapy in DLBCL.

The immunosuppressive effect of the programmed death (PD)-1/PD-L1 pathway plays an important role in the treatment of a variety of tumors, such as lung and breast cancer, but there is little literature about PD-1/PD-L1 in pheochromocytomas/paragangliomas (PCC/PGLs). We explored the relationship of PD-L1 and malignant behavior in 77 cases of PCC/PGL using immunohistochemistry (IHC) to assess protein expression and RNAscope to detect mRNA expression in 20 cases. The IHC data showed that 59.74% of the PCC/PGLs expressed PD-L1, and the extent of expression was highly correlated with Ki-67 (P = .019) and hypertension (P = .013), but not with age, sex, tumor size, capsular invasion, tumor necrosis, relapse/distant metastasis, secretion of noradrenaline/adrenaline/dopamine, or diabetes mellitus. In addition, we found an excellent correlation of PD-L1 mRNA and protein expression with a κ coefficient of 0.828, and further stratification of the IHC and RNAscope findings showed high consistency (Pearson's coefficient 0.753). The correlation of PD-L1 and Ki-67 indicated that PD-L1 could be considered a malignant proliferation biomarker for PCC/PGLs, which would be a putative biomarker for anti-PD-L1 therapies.