title: Cytotoxic and apoptogenic effects of Strobilanthes crispa Blume extracts on nasopharyngeal cancer cells.
abstract: The chemotherapeutic agents used to treat nasopharyngeal cancer (NPC) exhibit low efficacy. Strobilanthes crispa Blume is widely used for its anticancer, diuretic and anti‑diabetic properties. The present study aimed to determine the cytotoxic and apoptogenic effects of S. crispa on CNE‑1 NPC cells. A 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5 diphenyl tetrazolium bromide assay was used to evaluate the cytotoxic effects of S. crispa against CNE‑1 cells. The rate of apoptosis was determined using propidium iodide staining and caspase assays. Ethyl acetate, hexane and chloroform extracts of S. crispa leaves all exhibited cytotoxic effects on CNE‑1 cells, at a half maximal inhibitory concentration (IC50) of 119, 123.5 and 161.7 µg/ml, respectively. In addition, hexane, chloroform and ethyl acetate extracts of S. crispa stems inhibited CNE‑1 cell proliferation, at a IC50 of 49.4, 148.3 and 163.5 µg/ml, respectively. Flow cytometric analysis revealed an increased proportion of cells in the sub G1 phase and a decreased proportion of cells in the G2/M phase, following treatment with the extracts. However, the extracts did not alter the activities of caspase ‑3/7, ‑8 and ‑9. No cytotoxic effect was observed when the cells were treated with the methanol and water extracts of S. crispa stems and leaves. In conclusion, the S. crispa extracts were cytotoxic against CNE‑1 cells and these extracts were able to induce apoptosis, independent of caspase activation.
authors.affiliation: Department of Human Biology, School of Medicine, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Rhun Yian
authors.initials: RY
authors.lastname: Koh
authors.affiliation: School of Pharmacy and Health Sciences, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Yi Chi
authors.initials: YC
authors.lastname: Sim
authors.affiliation: School of Pharmacy and Health Sciences, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Hwee Jin
authors.initials: HJ
authors.lastname: Toh
authors.affiliation: School of Pharmacy and Health Sciences, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Liang Kuan
authors.initials: LK
authors.lastname: Liam
authors.affiliation: School of Pharmacy and Health Sciences, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Rachael Sze Lynn
authors.initials: RS
authors.lastname: Ong
authors.affiliation: Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 47500, Malaysia.
authors.forename: Mei Yeng
authors.initials: MY
authors.lastname: Yew
authors.affiliation: School of Postgraduate Studies and Research, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Yee Lian
authors.initials: YL
authors.lastname: Tiong
authors.affiliation: Department of Human Biology, School of Medicine, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Anna Pick Kiong
authors.initials: AP
authors.lastname: Ling
authors.affiliation: Department of Human Biology, School of Medicine, International Medical University, Kuala Lumpur 57000, Malaysia.
authors.forename: Soi Moi
authors.initials: SM
authors.lastname: Chye
authors.affiliation: Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor 47500, Malaysia.
authors.forename: Khuen Yen
authors.initials: KY
authors.lastname: Ng
mesh_terms: D027901:Acanthaceae / Q000737:chemistry*; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D002277:Carcinoma; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D053179:Caspase 7 / Q000235:genetics / Q000378:metabolism; D053181:Caspase 8 / Q000235:genetics / Q000378:metabolism; D053453:Caspase 9 / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D008826:Microbial Sensitivity Tests; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry
chemical_list: D000970:Antineoplastic Agents; D010936:Plant Extracts; C505407:CASP3 protein, human; C505520:CASP7 protein, human; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053179:Caspase 7; D053181:Caspase 8; D053453:Caspase 9