Preparation of dual drug-loaded polymer nanoconjugate to enhance treatment efficacy for ovarian cancer cells

Ovarian cancer is the deadliest gynecological malignancy, representing 2.5 % of all female cancers and accounting for 5 % of female cancer-related fatalities. Despite numerous strategies in its treatment, the disease shows a high recurrence rate and a low survival rate. Consequently, there is a growing focus on targeted therapies in ovarian cancer treatment. It is well-known that VEGFR and LPA pathways undergo alterations in ovarian cancer and stimulate survival, adhesion, migration, invasion, tumor growth and angiogenesis. Cabozantinib (CBZ) is a multi-receptor tyrosine kinase inhibitor that effectively targets MET, VEGFR-1, 2, 3, FLT3, c-KIT, and RET. Ki16425 is a selective inhibitor of LPA receptors 1, 2, and 3. Therefore, targeting LPA receptors and combining with VEGFR inhibitor is a strategic approach for ovarian cancer treatment. In this study, it was aimed to prepare polymer-drug nanoconjugate for both VEGFR and LPAR inhibition. For this, O-(2-Carboxyethyl) polyethylene glycol (PEG₅₀₀₀) which advantages are known in cancer studies, was chosen as the carrier system, and a nanoconjugate containing Ki16425 and CBZ (Ki-PEG-CBZ) was synthesized and its potential was evaluated. Initially, CBZ and Ki16425 were conjugated to the PEG₅₀₀₀ through pH-sensitive hydrazone and ester bonds. After nanoconjugate characterization, in vitro release and its ovarian cancer treatment potential were evaluated on A2780, OVCAR3 and SKOV3 ovarian cancer cell lines. A nanoconjugate was obtained with a particle size of 169 ± 15.23 nm, a zeta potential of −13.5 ± 1.21 mV, and a release profile lasting 48 h, containing CBZ and Ki16425 with drug loading efficiencies of 73.71 ± 0.53 % and 77.72 ± 2.51 %, respectively. In vitro studies have demonstrated that Ki-PEG-CBZ is highly effective against ovarian cancer. We suggest that the developed polymer-drug nanoconjugate is an effective and safe nanoconjugate for the treatment of ovarian cancer.