Deciphering the Interplay: Thieno[2,3-b]pyridine Impact on Glycosphingolipid Expression, Cytotoxicity, Apoptosis, and Metabolomics in Ovarian Tumor Cell Lines

Ovarian cancer is among the most common causes of female mortality. Despite improvements in diagnostic methods, non-specific symptoms and delayed gynecological exams can lead to late-stage ovarian tumor discovery. In this study, the effect of an anti-cancer compound, 3-amino-N-(3-chloro-2-methylphenyl)-5-oxo-5,6,7,8-tetrahydrothieno[2,3-b]quinoline-2-carboxamide (Compound 1) was examined. Cytotoxicity, apoptosis, and metabolomic changes in ovarian cancer cell lines SK-OV-3 and OVCAR-3, as well as glycosphingolipid (GSL) expression, both on cancer stem cells (CSCs), marked as CD49f+ and non-CSCs (CD49f-) were explored. Treatment with Compound 1 reduced the percentage of CSCs compared to non-treated cells (P < 0.001). The expression of eight GSLs on CSCs and non-CSCs was examined using flow cytometry. Both cell lines showed a change in the glycophenotype of the cells, either up or down of its expression, after the treatment. These findings raise the possibility of specifically targeting CSCs in ovarian cancer therapy. Additionally, treatment of Compound 1 resulted in a statistically significant increase in both early and late apoptosis (P<0.001) suggesting a pivotal role in initiating programmed cell death by the apoptotic pathway. The metabolic analysis revealed that the treated cancer cells showed reduced metabolic activity compared to the control group (P < 0.001)