C-71980262, a novel small molecule against human papilloma virus-16 E6 (HPV-16 E6) with anticancer potency against cervical cancer: A computational guided in vitro approach.

Objectives: Human papillomavirus-16 E6 (HPV-16 E6) forms a heterodimer complex to up-regulate the degradation of tumor suppressor protein p53 to promote cervical cancer. This study aims to identify a novel small molecule against E6 with anticancer efficacy against HPV-16, a prime high-risk serotype inducer for cervical cancer.

Materials and methods: Autodock-vina-based high-throughput virtual screening and atomistic molecular dynamic simulations were used for identification of targeted lead molecules. HPV-16 infected SiHa and CaSki cell lines were used to validate the lead compound in vitro. Proliferation of cancer cells was analyzed by MTT assay and flow cytometry was used to analyze target inhibition, apoptosis, and p53.

Results: High throughput virtual screening and molecular dynamic simulation identified C-71980262 as a lead candidate that could bind HPV-E6. Atomistic molecular dynamic simulation of E6 bound C-71980262 for 200 ns showed that the predicted ligand binding was stable with minimal energy expenditure, proposing the viability and veracity of the assessed molecule. C-71980262 inhibited the proliferation of SiHa and CaSki cells with GI50 values of 355.70 nM and 505.90 nM, respectively. The compound reduced HPV-16 E6 while inducing early and late-phase apoptosis in these cells. Treatment with C-71980262 increased the p53-positive populations in SiHa and CaSki cells.

Conclusion: C-71980262 was identified as a novel lead molecule that could inhibit the HPV-16 E6 and increase p53 in cervical cancer cells. Further in vitro and in vivo validation is warranted to consolidate and corroborate this lead compound against HPV-induced cancer progression.