Expression of Yes-associated protein in cervical squamous epithelium lesions

Yes-associated protein (YAP) was defined as a candidate oncogene in multiple cancers. Yet, the role of YAP in cervical cancer is largely unknown. The aim of this study was to determine whether YAP could be used as a predictive biomarker in cervical precancerous lesions.

Immunohistochemical analysis of YAP expression was performed in 10 chronic cervicitis, 49 cervical intraepithelial neoplasia (CIN) 1, 55 CIN 2, 34 CIN 3, and 32 cervical squamous cell carcinoma (SCC) samples. Human papillomavirus (HPV) was detected by HPV genotype detection kit in 70 cases including 10 chronic cervicitis cases, 13 CIN 1 cases, 19 CIN 2 cases, 14 CIN 3 cases, and 14 SCC cases. Furthermore, the relationship between YAP expression and HPV integration status was analyzed using Spearman rank correlation coefficient test.

Samples of chronic cervicitis had negative or weak expression of YAP in cytoplasm. In the CIN 1 group, YAP expression was primarily confined to the lower third part of squamous epithelia or basal layer, whereas higher-grade CIN (2 and 3) and SCC groups had a strong nuclear expression of YAP. The expression levels of YAP in chronic cervicitis and CIN 1 were significantly lower compared to those in higher-grade CIN and SCC. Moreover, YAP expression was correlated with HPV integration status. Most high-risk HPV(+)/YAP(+) cases were found in the CIN 3 and SCC groups.

This study suggested that YAP could function as a predictive marker in CIN and cervical cancer. YAP expression, in combination of HPV, might facilitate the identification of precancerous cervical lesions.