Connexin 43 Expression as Biomarker of Oral Squamous Cell Carcinoma and Its Association with Human Papillomavirus 16 and 18.

Oral squamous cell carcinoma (OSCC) is the main form of head and neck cancer. Gap junctions (GJs) are communication channels involved in cell proliferation control; they consist of hemichannels formed by connexin (Cx) proteins. The abnormal expression/function of Cx43 has been associated with tumor progression. Also, some human papillomaviruses (HPVs) have been linked to squamous cell cancer. Therefore, this study aimed at assessing Cx43 as a potential OSCC biomarker and exploring its association with histopathological differentiation and HPV infection. OSCC samples were inspected using hematoxylin and eosin staining, and Cx43 expression and HPV 16/18 were tested by immunofluorescence. Pearson correlation tests, ANOVA, and Kaplan-Meier curves were used in the analysis. Samples from 39 patients with OSCC were studied. Most had well-differentiated histology and 61.5% were HPV+. Cx43 expression was significantly associated with HPV infection (p = 0.047), differentiation (p < 0.001), and survival (p = 0.009), and HPV positivity was also associated with the degree of differentiation (p = 0.012). Cx43 shows potential as a prognostic biomarker for OSCC. Lower Cx43 expression, correlated with poorer differentiation, is associated with an unfavorable prognosis. Further studies are needed to confirm its clinical utility.