New Insights into COL26A1 in Thyroid Carcinoma: Prognostic Prediction, Functional Characterization, Immunological Drug Target and ceRNA Network

Abstract Backgrounds: Collagen is the main component in extracellular matrix. More and more researches have determined the oncogenic effect of collagen in cancer progression, which is intriguing to be further explored. Collagen type ⅩⅩⅥ alpha 1 chain (COL26A1) is a newly discovered collagen subtype, functions of which still remain poorly demonstrated. No studies have reported the roles of COL26A1 in human cancers ever before. Thus we tried to initially explore the potential associations between COL26A1 and thyroid carcinoma (THCA), in an attempt to enrich the relevant literature, serving as basis for further elucidation and experimental validation. Results: We processed a series of bioinformatic analysis for exploration, which mainly distributed to 4 aspects: Prognostic/diagnostic prediction, functional characterization, immunological target and ceRNA network. We found that high expression level of COL26A1 infers poor prognosis for patients with THCA. The aberrant expression of COL26A1 could be applied as diagnostic and prognostic biomarker with a certain degree of accuracy. Besides, a novel nomogram containing several independent prognostic factors was established to predict the survival probability of patients with THCA. Functional characterizations implied that COL26A1 is tightly associated with immunological processes, as well as several oncogenic signaling pathways. Subsequently, we determined that high COL26A1 expression is accompanied by higher infiltration levels of multiple immune cells and higher stromal/immune score. Also, the significantly positive correlations of COL26A1 expression with infiltration levels of multiple immune cells and stromal/immune score were determined. In addition, we identified that COL26A1 is significantly positively co-expressed with most immune checkpoints, including PD1, PD-L1, TIGIT, LAG3 and CTLA4. The drugs that can decrease the expression level of COL26A1 were also identified. The predicted lncRNA-miRNA-COL26A1 regulatory axes were displayed. Conclusions: Our work has primarily appraised COL26A1 as a promising biomarker for diagnosis/prognosis and target for immunotherapy in THCA.