Clinical significance of COL1A1 and COL1A2 expression levels in hypopharyngeal squamous cell carcinoma

Alterations in collagen type I α1 (COL1A1) and collagen type I α 2 (COL1A2) expression levels have been reported to predict prognosis in various types of cancer. However, the effect of these biomarkers on hypopharyngeal squamous cell carcinoma (HPSCC) is yet to be fully elucidated. The present study aimed to explore the prognostic significance of COL1A1 and COL1A2 expression levels in HPSCC. The expression levels of COL1A1 and COL1A2 in 67 patients with HPSCC were examined using an immunohistochemical assay in a tissue microarray. The associations between COL1A1/COL1A2 expression levels and patient clinicopathological features were analyzed using ANOVA, Pearson's χ(2) or Fisher's exact test. The Cox proportional hazard models and Kaplan-Meier survival analysis with log-rank tests were used to analyze the significance of COL1A1/COL1A2 as prognostic markers for patients with HPSCC. As a result, immunohistochemical staining revealed that COL1A1 was positively expressed in all cases, among which 40.3% were strong positive, while COL1A2 was positively expressed in 76.1% of the HPSCC cases with 6.0% of the samples exhibiting strong staining. Further analysis revealed no significant association between the expression levels of COL1A1/COL1A2 and other clinicopathological features. Cox regression analysis revealed that a high COL1A2 expression level predicted a high locoregional recurrence and a less favorable disease-free survival rate (P=0.042 and 0.020, respectively). Overall, the present study indicated that COL1A2 expression levels may have value as a prognostic indicator in HPSCC.