Objective: To explore the interaction between folate and the expression of HPV16 E6/E7 mRNA in the progression of cervix carcinogenesis.
Methods: Subjects were selected from the participants who were diagnosed pathologically, including 64 patients with cervical squamous cell carcinoma (SCC), 55 patients with low-grade cervical intraepithelial neoplasm (CIN1), 55 patients with high-grade cervical intraepithelial neoplasm (CIN2+) and 80 with normal cervix (NC). The levels of serum folate and RBC folate were detected by microbiological assay, and the expression levels of HPV16 E6/E7 mRNA were measured, using the real-time polymerase chain reaction (real-time PCR). Data was analyzed by methods as chi-square test, analysis of variance (ANOVA), Welch test, Kruskal-Wallis H test and ordinal logistic regression. Spearman correlation was tested using the SPSS statistical software (version 16.0) while the interaction effects were evaluated by additive model.
Results: There was a positive correlation seen between the serum folate and RBC folate (r=0.41, P<0.001). The levels of serum folate and RBC folate decreased gradually along with the severity of cervical lesions (χ(2)=32.71, P<0.001; χ(2)=16.32, P<0.001). The expression levels of HPV16 E6/E7 mRNA increased gradually with the severity of cervical lesions (χ(2)=30.11, P<0.001; χ(2)=38.99, P<0.001). There was a negative correlation between the levels of RBC folate, expression levels of HPV16 E6 (E6: r=-0.14, P=0.009) and HPV16 E7 mRNA (E7: r=-0.21, P=0.001), respectively. Both RBC folate deficiency and HPV16 E6/E7 mRNA high expression showed additive interaction in CIN1,CIN2+ and SCC.
Conclusion: Folate deficiency and high expression of HPV16 E6/E7 mRNA might increase the risk of cervical cancer and cervix precancerous lesions, and having a synergistic action in the progression of cervix carcinogenesis.