Sinomenine derivative S14 inhibits cervical cancer cell growth by targeting AKT-CyclinD1-p21/p27 pathway

Cervical cancer remains a leading cause of female malignancy globally, with current therapeutic options often limited by systemic toxicity and inadequate efficacy. The PTEN/PI3K/AKT pathway is frequently dysregulated in this cancer, contributing to disease progression and treatment resistance. Sinomenine, a natural isoquinoline alkaloid, shows moderate anticancer potential, but its activity requires structural modification to improve its therapeutic index and overcome these limitations. This highlights a critical need for novel, more potent compounds that can specifically target key oncogenic pathways.

Researchers synthesized 15 sinomenine derivatives through Ritter reaction-mediated amidation and C-4 esterification, then evaluated their in vitro anticancer activities. The most potent compound, S14, was tested against three cervical cancer cell lines (HeLa, SiHa, C33A) using MTT assay to determine IC₅₀ values. Further characterization of S14 in SiHa cells involved colony formation, wound healing, and Transwell experiments to assess proliferation, migration, and invasion. Flow cytometry analyzed cell cycle arrest and apoptosis, while Western blot determined protein expression changes. AKT silencing via siRNA transfection was used to confirm mechanistic involvement.

Among the synthesized derivatives, S14 demonstrated the most potent cytotoxicity against cervical cancer cell lines. > S14 exhibited potent cytotoxicity with IC₅₀ values of 1.96 ± 0.08 µM against SiHa cells, 3.32 ± 0.31 µM against HeLa, and 6.20 ± 0.55 µM against C33A cells. S14 inhibited SiHa cell proliferation, migration, and invasion in a concentration-dependent manner. Flow cytometry revealed that S14 induced G₂/M phase cell cycle arrest and late apoptosis in SiHa cells. Mechanistically, Western blot assays showed S14 significantly downregulated AKT, phosphorylated AKT (p-AKT), and CyclinD1 expression, while concurrently upregulating the cyclin-dependent kinase inhibitors p21 and p27. This indicates a clear involvement of the AKT-CyclinD1-p21/p27 signaling pathway. Crucially, AKT silencing via siRNA transfection significantly attenuated S14-induced cell cycle arrest and apoptosis, confirming AKT as a key target.