HPV Infection and its Relationship with Expression of PIK3CA, PIK3CB in Esophageal Squamous Cells Carcinoma

Abstract Background: Esophageal squamous cell carcinoma (ESCC) is a highly lethal cancer. Human papillomavirus (HPV) is currently considered as a potential risk factor for ESCC, but this assumption is still contradictory. P16INK4a (p16) staining can be used as an alternative marker of HPV oncogene activity. This study was to investigate the role of HPV in esophageal cancer and to compare the relationship between HPV status and PIK3CA, PIK3CB. Methods: Immunohistochemistry, Western blot, and RT-PCR analyses were performed to detect the expression of p16, PIK3CA, PIK3CB and p53 in 156 cases of esophageal squamous cell carcinoma. The patients were followed up by telephone or clinic. Results: The positive rates of p16, PIK3CA, PIK3CB and p53 in esophageal squamous cell carcinoma were significantly higher than those in normal esophageal mucosa. The overexpression of p16 was closely related to tumor location, TNM stage, differentiation and lymph node metastasis. In addition, the expression of p16 was positively correlated with the expression of PIK3CA, but not with the expression of PIK3CB and p53. Survival analysis showed that p16 was a good prognostic marker, while PIK3CA and p53 were poor prognostic markers. Conclusions: HPV infection is associated with ESCC. The imbalance of PI3K/Akt signaling pathway is closely related to HPV infection and prognosis. Detection of p16 and PIK3CA is of great significance in evaluating the prognosis and optimizing the treatment of esophageal squamous cell carcinoma.