Abstract B28: FKBP6 gene is involved in progression of cervical cancer

Abstract

Abstract Introduction: Cervical Cancer (CC) is an important heath problem in developing countries. The silencing of tumor suppressor genes (TSG) could be implied in cervical carcinogenesis. Methylation microarray showed an aberrant hypermethylation of FKBP6, a potential TSG gen in CC. The aim of this study was to characterizer FKBP6 role in cervical carcinogenesis. Materials and methods: ECT1 E6/E7 (immortalized normal squamous epithelia cell line) and three CC cell lines: SiHa, C-4I and C-33A were cultivated for experiments. FKBP6 expression was determined by qRT-PCR and western blot. Treatment with 10 μM 5-aza-2′deoxycytidine (5-aza) was performed to evaluate a possible epigenetic regulation. Transfection with pCMV6-FKBP6-GFP (FKBP6) and pCMV6-GFP (Empty) was carried out in SiHa cell line through lipofection followed by G418 selection to obtain stable transfection. Viability and clonogenic assay was performed to evaluate transfected cell behaviour. In other hand, 497 biopsy samples of the cervix were analyzed by FKBP6 immunohistochemistry (48 normal; 192 low-squamous intraepithelial lesions; 200 high- squamous intraepithelial lesions and 57 squamous cervical cancers). Results: FKBP6 mRNA and protein expression was significantly downregulated in all cervical cancer cell lines respect to ECT1 E6/E7. In western blot, also could be observed a variant of FKBP6 mainly in C-4I cell line. After treatment with 5-aza, mRNA (p<0.001) and protein expression of FKBP6 of all CC cell lines were restored. FKBP6 transfected SiHa showed a significant colony formation (p<0.05) decrease. However, cell viability was found incremented (p<0.001) compared with SiHa transfected with the empty vector. Immunohistochemistry showed an increased expression of FKBP6 in cervical cancer compared with normal (p<0.001). Conclusions: There is a FKBP6 dysregulation in CC cell lines, and the inactivation mechanism seems to be methylation. Restored expression of FKBP6 in SiHa cell line modifies the tumor phenotype, decreasing colony formation, but increasing cell viability. These results suggest that FKBP6 could be implied in cervical progression, but more studies are necessary to evaluate FKBP6 functions in cervical cancer. Acknowledgments: FONDECYT N°3130630, Project Corfo N° 09CN14-5960, Project Corfo N°12IDL2-18157. Project FONDECYT N° 11150802, Project FONDECYT N°1115062 Citation Format: Carmen Gloria Ili, Tamara Viscarra, Juan Carlos Araya, Jaime Lopez, Barbara Mora, Javier Retamal, Susana Aedo, Enrique Bellolio, Juan Carlos Roa, Priscilla Brebi. FKBP6 gene is involved in progression of cervical cancer. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Cancer Cell Cycle - Tumor Progression and Therapeutic Response; Feb 28-Mar 2, 2016; Orlando, FL. Philadelphia (PA): AACR; Mol Cancer Res 2016;14(11_Suppl):Abstract nr B28.