Cytotoxic Effects of Combinative ZnPcS 4 Photosensitizer Photodynamic Therapy (PDT) and Cannabidiol (CBD) on a Cervical Cancer Cell Line

• Published in: International journal of molecular sciences Vol. 24; no. 7
• Main Authors: Razlog, Radmila, Kruger, Cherie Ann, Abrahamse, Heidi
• Format: Journal Article
• Language: English
• Published: Switzerland 24.03.2023
• Subjects: Antineoplastic Agents - therapeutic use; Cannabidiol - pharmacology; Cannabidiol - therapeutic use; Cell Line, Tumor; Female; HeLa Cells; Humans; Photochemotherapy - methods; Photosensitizing Agents - pharmacology; Photosensitizing Agents - therapeutic use; Uterine Cervical Neoplasms - pathology; HeLa; ZnPcS4; phthalocyanines; cannabidiol (CBD); photodynamic therapy (PDT); cervical cancer; photosensitizer
• ISSN: 1422-0067

The most prevalent type of gynecological malignancy globally is cervical cancer (CC). Complicated by tumor resistance and metastasis, it remains the leading cause of cancer deaths in women in South Africa. Early CC is managed by hysterectomy, chemotherapy, radiation, and more recently, immunotherapy. Although these treatments provide clinical benefits, many patients experience adverse effects and secondary CC spread. To minimize this, novel and innovative treatment methods need to be investigated. Photodynamic therapy (PDT) is an advantageous treatment modality that is non-invasive, with limited side effects. The L. plant isolate, cannabidiol (CBD), has anti-cancer effects, which inhibit tumor growth and spread. This study investigated the cytotoxic combinative effect of PDT and CBD on CC HeLa cells. The effects were assessed by exposing in vitro HeLa CC-cultured cells to varying doses of ZnPcS photosensitizer (PS) PDT and CBD, with a fluency of 10 J/cm and 673 nm irradiation. HeLa CC cells, which received the predetermined lowest dose concentrations (ICD ) of 0.125 µM ZnPcS PS plus 0.5 µM CBD to yield 50% cytotoxicity post-laser irradiation, reported highly significant and advantageous forms of cell death. Flow cytometry cell death pathway quantitative analysis showed that only 13% of HeLa cells were found to be viable, 7% were in early apoptosis and 64% were in late favorable forms of apoptotic cell death, with a minor 16% of necrosis post-PDT. Findings suggest that this combined treatment approach can possibly induce primary cellular destruction, as well as limit CC metastatic spread, and so warrants further investigation.