Zeitschrift für Karzinogenese und Mutagenese

Abstrakt

Concomitant Therapy of Aq. Theobroma Extract and Doxorubicin Reduces Stemness and Induces Ferroptosis in Therapeutic Resistant Cervical Cancer Cells

Prasanthi Chittineedi, Santhi Latha Pandrangi*, Gooty Jaffer Mohiddin, Juan Alejandro Neira Mosquera, Sungey Naynee Sánchez Llaguno

Background: Doxorubicin (Dox) is one of the potent antineoplastic drugs currently used as a chemotherapeutic agent for several cancers. Numerous studies suggested that multiple chemotherapeutic cycles with Dox might lead to development of drug resistance and cardiotoxicity in patients leading to poor prognosis, and survival outcome. Present study aims to lower the drug dosage of Dox without altering its antitumor potential. Aqueous Theobroma Extract (ATE) has been reported previously to have several anti-tumor properties and is known to be used as a traditional medicine in the treatment of various diseases without any adverse effects like cardiotoxicity and hepatoxicity. In the present study we demonstrate that ATE when used in combination with Dox exhibited a synergistic antitumor effect, sensitizes therapeutic resistant cervical cancer cells through induction of ferroptosis thereby reducing both the dosage and adverse side effects imposed by this chemotherapeutic drug.

Materials and Methods: Initially, we developed carboplatin-resistant cervical cancer cells for analyzing the antitumor effects of ATE and the synergistic effects of ATE with respect to Dox. Gene expression analysis using RT-PCR and flow cytometry studies were performed to analyze the expression of target genes. Intracellular ferritin levels, lipid ROS levels were estimated to check ferroptosis induction. Lastly cell cycle analysis and apoptosis analysis were performed to confirm cell death.

Results: Previous studies demonstrated that CSCs are the root cause of cancer and are responsible for tumor recurrence and relapse. Hence it is imperative but these CSCs should be targeted to achieve complete cure for cancer. ATE showed synergistic anticancer effects with respect to Dox and potentially induced cancer cell death in drug- resistant cervical cancer cells by triggering both apoptosis and ferroptosis by downregulating Bcl-2 and degrading ferritin respectively. Also, ATE in combination with Dox reduced the expression of stem cell markers which are evaluated by RT-PCR and flow cytometry. On the other hand, cell cycle analysis and apoptosis analysis suggest that the cell has been arrested through cell death induction. Interestingly, dox when used with ATE potentially induced cancer cell death in drug-resistant cervical cancer cells at lower concentrations. Our results suggest that reduced concentration of Dox in combination with ATE induces cancer cell death through induction of ferroptosis and also reduces the risk of cardiotoxicity.

Conclusion: Based on our results, we conclude that ATE and Dox combination therapy reduces drug-resistance and enhances cervical cancer prognosis associated with reduction of Dox dosage also protecting the cells from cardiotoxicity.