The intercorrelation among CCT6A, CDC20, CCNB1, and PLK1 expressions and their clinical value in papillary thyroid carcinoma prognostication

BACKGROUND: CCT6A promotes several carcinomas' growth and invasion in multiple ways, and it relates to CCNB1 and PLK1 through its interaction with CDC20 via protein–protein interaction bioinformatics. This study aimed to explore the intercorrelation among CCT6A, CDC20, CCNB1, and PLK1, and their association with tumor features and prognosis in papillary thyroid carcinoma (PTC) patients. METHODS: CCT6A, CDC20, CCNB1, and PLK1 expressions in 186 tumor and 30 non‐tumor specimens from PTC patients were determined by immunohistochemical (IHC). Clinical features, disease‐free survival (DFS), and overall survival (OS) were retrieved. RESULTS: CCT6A, CDC20, CCNB1, and PLK1 expressions were upregulated in tumor tissues compared with non‐tumor tissues (all p < 0.001). CCT6A expression positively correlated with CDC20, CCNB1, and PLK1 expressions; besides, CDC20 expression positively associated with CCNB1 and PLK1 expressions, and CCNB1 expression was also positively related to PLK1 expression (all p < 0.05). Moreover, elevated tumor CCT6A expression was correlated with extrathyroidal invasion (p = 0.015), higher pT stage (p < 0.001), pN stage (p = 0.046), and pTNM stage (p = 0.042); while tumor CDC20, CCNB1, and PLK1 expressions only correlated with some of these indexes (most p < 0.05). Notably, CCT6A and CDC20 high expressions predicted worse DFS and OS (all p < 0.05); CCNB1 positive expression only predicted poor DFS (p = 0.044) but not OS (p = 0.152); however, PLK1 expression failed to predict these two indexes (both p > 0.05). After adjustment using multivariate Cox's regression, CCT6A expression (high vs. low) independently estimated shorter DFS (p = 0.010) and OS (p = 0.006). CONCLUSION: CCT6A, CDC20, CCNB1, and PLK1 are intercorrelated, and they exhibit certain prognostic values in PTC patients.