Downregulated granzyme M expression: implications for the immune system and prognosis of thyroid cancer.

Thyroid carcinoma (THCA), the most prevalent endocrine system cancer, is rising worldwide. Granzyme family member GZMM causes tumor cell inflammation and programmed cell death. However, the role of GZMM in THCA has not been investigated. Bioinformatics analysis and assays showed that THCA GZMM protein levels were down-regulated and associated with certain clinicopathological features. Additionally, univariate and multivariate Cox analysis and ROC curve analysis showed that low GZMM expression was related with poor overall survival and might be employed as a prognostic and diagnostic factor. We used functional tests to examine how GZMM affected angiogenesis, invasion, and migration in vitro. TIMER showed a link between GZMM expression, immune cell infiltration, and tumor purity. Overexpression of GZMM also greatly boosted CD8 + T cell-attracting chemokines. TCGA data analysis yielded a GZMM and epigenetic modification-related gene risk prediction model. Overall, GZMM inhibits tumor invasion, migration, and angiogenesis, and is closely related to the immune microenvironment, significantly associated with poor prognosis in THCA patients.