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Background: Immunotherapy has been a promising treatment in advanced lung cancer. However, only a few patients could benefit from it. Herein, we aimed to explore mutationrelated predictive biomarkers in lung squamous cell carcinoma (LUSC), which could help develop clinical immunotherapy strategies and screen beneficial populations., Methods: Co-occurrence and mutually exclusive analysis was conducted on the TCGA-LUSC cohort. Correlations between the gene mutation status and tumor mutation burden (TMB) levels, and neo-antigen levels were analyzed by Wilcoxon test. Kaplan-Meier method was employed to analyze the progression-free survival (PFS) of lung cancer patients with immunotherapy. Gene set enrichment analysis (GSEA) was used to investigate the functional changes affected by TP53 mut /TTN mut . The immune cell infiltration landscape in co-mutation subgroups was analyzed using CIBERSORT., Results: 1) TP53, TTN, CSMD3, MUC16, RYR2, LRP1B, USH2A, SYNE1, ZFHX4, FAM135B, KMT2D, and NAV3 were frequently mutated in LUSC patients. 2) TMB levels in highly mutated groups were higher than that in wild type groups. 3) There were higher neoantigen levels in mutation group compared to the wild-type group, and LUSC patients in mutation group had longer PFS. 4) TP53 mut /TTN mut co-mutation group exhibited higher TMB levels and better response to immunotherapy. 5) A host of immune-related signaling pathways was inhibited in TP53 mut /TTN mut subgroup. 6) There were more T follicular helper cells and NK cells were in TP53 mut /TTN mut subgroup than in the WT subgroup., Conclusion: The LUSC patients with TP53 and TTN co-mutation had higher TMB levels and better response to immunotherapy. The TP53 and TTN co-mutation is a promising novel biomarker to assist LUSC immunotherapy evaluation., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Dehydroleucodine, a natural sesquiterpene lactone from Artemisia douglassiana Besser (Argentine) and Gynoxys verrucosa (Ecuador)., Objective: To define the molecular mechanisms underlying the effect of dehydroleucodine on the human glioblastoma cells., Method: Various techniques (cDNA expression array, real-time quantitative PCR, chromatin immunprecipitation, luciferase reporter assay, use of phosphospecific antibodies, immunoprecipitation, immunoblotting, apoptosis and autophagy assays) were employed to define and validate multiple molecular gene targets affected in human glioblastoma cells upon dehydroleucodine exposure., Results: Dehydroleucodine exposure upregulated the total and phosphorylated (p-Y99) levels of TP73 in U87- MG glioblastoma cells. We found that TP73 silencing led to a partial rescue of U87-MG cells from the cell death induced by dehydroleucodine. Upon the dehydroleucodine exposure numerous gene targets were upregulated and downregulated through a TP73-dependent transcriptional mechanism. Some of these gene targets are known to be involved in cell cycle arrest, apoptosis, autophagy and necroptosis. Dehydroleucodine induced the TP73 binding to the specific genes promoters (CDKN1A, BAX, TP53AIP1, CYLD, RIPK1, and APG5L). Moreover, the exposure of U87-MG cells to dehydroleucodine upregulated the protein levels of CDKN1A, BAX, TP53AIP1, CYLD, RIPK1, APG5L, and downregulated the CASP8 level. The formation of RIPK1 protein complexes and phosphorylation of MLKL were induced by dehydroleucodine supporting the notion of multiple cell death mechanisms implicated in the tumor cell response to dehydroleucodine., Conclusion: This multifaceted study led to a conclusion that dehydroleucodine induces the phosphorylation of tumor protein TP73 and in turn activates numerous TP73-target genes regulating apoptosis, autophagy and necroptosis in human glioblastoma cells.., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)