Human papilloma virus E1-specific T cell immune response is associated with the prognosis of cervical cancer patients with squamous cell carcinoma

Cervical cancer is attributable to human papilloma virus (HPV) infection in the majority cases. E1, an HPV derived-protein, plays an important role in the initiation and development of cervical cancer. Our study aims to investigate the HPV E1-specific T cell response in patients with cervical squamous cell carcinoma (CSCC).

Our study demonstrated that the level of HPV E1-specific T cell response was correlated with the survival of advanced patients with CSCC. Patients who displayed no HPV E1-specific T cell response were more likely to be those with poor prognosis.

A total of 66 CSCC patients with FIGO stage IIB-IIIB and 60 healthy controls were enrolled. Enzyme-Linked ImmunoSpot (ELISPOT) assays was used to measure the HPV E1-specific T cell response in the peripheral blood of these patients before treatment. The patients were treated with chemotherapy and/or radiotherapy and followed up clinically for three years. The relationship between the T cell response, various clinical characteristics and the prognosis were studied with univariate analysis, multivariate analysis and survival curve analysis.

The frequency of HPV E1-specific T cell response in peripheral blood of cervical cancer patients was 59.09%, with mean response intensity 24.56 SFC/106 PBMCs. The frequency and intensity of HPV E1-specific T cell response in patients were higher than healthy controls(p < 0.001; p = 0.009). The intensity of HPV E1-specific T cell responses were higher in the stage IIB patients and patients with no pelvic lymph node metastasis (p = 0.038; p = 0.044). Univariate analysis showed that HPV E1 specific T cell response was associated with progression-free survival (PFS) and overall survival (OS) (PFS: p = 0.021; OS: p = 0.004). Multivariate analysis showed that HPV E1-specific T cell response was an independent prognostic factor influencing PFS and OS among all the factors included in our study (PFS: HR = 7.252, 95%CI = 1.690-31.126, p = 0.008; OS: HR = 7.499, 95%CI = 1.661-33.856, p = 0.009). The survival curves showed that the rate of PFS and OS in patients with HPV E1 specific T cell response was significantly higher than those who did not response. Conclusions: Our study demonstrated that the level of HPV E1-specific T cell response was correlated with the survival of advanced patients with CSCC. Patients who displayed no HPV E1-specific T cell response were more likely to be those with poor prognosis.