title: Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica papaya Leaf Extracts.
abstract: In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high levels of phenolic and flavonoid compounds. The chromatographic and mass spectrometric profiles of the extracts obtained with Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry were used to tentatively identify the bioactive compounds using comparative analysis. The principal compounds identified were flavonoids or flavonoid glycosides, particularly compounds from the kaempferol and quercetin families, of which several have previously been reported to possess anticancer activities. These results confirm that papaya leaf is a potential source of anticancer compounds and warrant further scientific investigation to validate the traditional use of papaya leaf to treat cancer.
authors.affiliation: School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia. t.nguyen65@uq.edu.au.
authors.forename: Thao T
authors.initials: TT
authors.lastname: Nguyen
authors.affiliation: School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia. m.parat@pharmacy.uq.edu.au.
authors.forename: Marie-Odile
authors.initials: MO
authors.lastname: Parat
authors.affiliation: School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia. m.hodson1@uq.edu.au.|Metabolomics Australia, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia. m.hodson1@uq.edu.au.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Hodson
authors.affiliation: School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia. jenny.pan@uqconnect.edu.au.
authors.forename: Jenny
authors.initials: J
authors.lastname: Pan
authors.affiliation: School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia. n.shaw@pharmacy.uq.edu.au.
authors.forename: Paul N
authors.initials: PN
authors.lastname: Shaw
authors.affiliation: School of Pharmacy, The University of Queensland, Brisbane, QLD 4072, Australia. a.hewavitharana@pharmacy.uq.edu.au.
authors.forename: Amitha K
authors.initials: AK
authors.lastname: Hewavitharana
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D002294:Carcinoma, Squamous Cell; D029441:Carica; D002460:Cell Line; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D005419:Flavonoids / Q000032:analysis; D006801:Humans; D013058:Mass Spectrometry; D010636:Phenols / Q000032:analysis; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves
chemical_list: D000970:Antineoplastic Agents; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts
keywords: Carica papaya; cancer; chromatography; cytotoxicity; flavonoids; mass spectrometry