Human PDCD1 blocking peptide

Objectives/Hypothesis To investigate differences in the immunogenomic landscape among young patients presenting with oral cavity squamous cell carcinoma (OCSCC). Study Design Retrospective database review. Methods Normalized messenger mRNA expression data were downloaded from The Cancer Genome Atlas (TCGA) database. OCSCC patients were categorized into young and older age groups with a cutoff of 45 years. Human papillomavirus-positive tumors were excluded. Cell fractions, marker expression, and mutational load were compared between age groups using the Wilcoxon rank sum test. Adjustment for multiple comparisons was performed using the Benjamini-Hochberg method, with a false discovery rate of 0.05. Results Two hundred forty-five OCSCC tumors were included; 21 (8.6%) were young (37.1 +/- 7.5 years) and 224 (91.4%) were older (64.5 +/- 10.3 years). There was no significant difference between groups in the fraction of B and T lymphocytes, macrophages, monocytes, natural killers, and dendritic cells. Cytolytic activity score was decreased in young patients (8.33 vs. 18.9, P = .023). Additionally, young patients had significantly lower expression of immunomodulatory markers of immune activation, including PD-1 (PDCD1, P = .003), CTLA4 (P = .025), TIGIT (P = .002), GITR (TNFRSF18, P = .005), OX40 (TNFRSF4, P = .009), LAG-3 (P < .001), and TIM-3 (HAVCR2, P = .002). Young patients had a significantly lower number of single nucleotide variant-derived neoantigens (26.2 vs. 60.6, P < .001). Conclusions OCSCC patients aged 45 years and younger appear to have an attenuated immune response that may be related to a lower frequency of immunogenic mutations. This may contribute to the pathogenesis of these tumors, and ultimately help inform personalized immune-based therapeutic strategies for young patients with OCSCC. Level of Evidence NA Laryngoscope, 2020

MicroRNA-143 has been implicated in tumor metastasis by directly targeting Bcl-2, and microRNA-143 expression is decreased in several human tumors. However, the expression and targets of miR-143 in radiation carcinogenesis remain unclear. We found that the expression of miR-143 is down-regulated and the expression of B7H1 (Pdcd1) is up-regulated in radiation-induced thymic lymphoma model in BALB/c mice. Additionally, overexpression of miR-143 strongly inhibited cell proliferation and increased cell apoptosis and its down-regulation promoted cell proliferation and reduced cell apoptosis. We also determined that there is an inverse correlation between miR-143 expression and B7H1 protein expression in radiation-induced thymic lymphoma samples, and miR-143 targets B7H1 in a 3'UTR-dependent manner. In addition, we found that adenovirus overexpression of pre-miR-143 reduced tumorigenesis in vivo. Finally, we conclude that down-regulated expression of miR-143 and up-regulation of its direct target B7H1 may indicate a novel therapeutic method for radiation-induced thymic lymphoma by increased expression of miR-143 or inhibition of B7H1.