Evaluation of the anticancer properties of the methanol leaf extract of Chromolaena odorata on HT29 lung cancer cell line

Plant materials have been used for medicinal purposes since ancient time because cost, availability, accessibility and effectiveness are some of the reasons attributable for its widespread use in modern times. Researches on plant based scientific works being are being carried out so as to discover/develop lead agents which can be used to meet the numerous health challenges of man. One of the plants in this regard is Chromolaena odorata . Chromolaena odorata , regarded as an invasive weed, has been used in Indonesia, Thailand, Malaysia, Vietnam and parts of Africa including Nigeria as a hemostatic, anti‐inflammatory drug, and for intestinal diseases and burns. Studies about its antioxidant, antibacterial, and antigonorrhea effects have been reported. Its phytochemical investigations revealed the presence of flavonoids, alkaloids, and terpenoids [1, 2]. In this study, cell viability and other properties of this plant alone and in the presence of VEGF and ET‐1 on HT29 cell lines were examined. Materials and Methods The effect of methanol leaf extract of Chromolaena odorata (MLECO) on cell proliferation in HT29 cells was investigated using the using the Cell Titer 96 MTT Proliferation Assay. The viable cells were seeded at a density of 5 × 10 4 (100 μL/well) in 96‐well plates and incubated in a humidified atmosphere of 5% CO 2 and 95% air at 37°C for 24h to form a cell monolayer. After 24h, the supernatant on the monolayer was aspirated and 100 μL of medium and varying log concentrations of extract (100–700 μg/mL) were added and incubated for 24, 48, and 72 h time points. After the specific times of exposure to the extract, 20 μL of 5mg/mL MTT in PBS was added to each well and incubated for 3 h at 37°C in a 5% CO 2 atmosphere. Supernatants were removed and 150 μL of isopropanol was added and the plates were gently shaken for 15min to solubilize the formazan crystals and absorbance was measured at 560 nm using BioTex ELX 800 plate reader. In another study, the effects of Chromolaena odorata alone and with mitogens (VEGF and ET‐1) on lung cancer cell lines (HT29) viability after 24 and 48 hours were investigated. Results and Discussion MTT assay showed that after 72 hours, the extract caused marked inhibitory effects on the cancer cell lines with lower concentration showing greater effect. When the plant extract was incubated alone with cancer cell lines at 200 and 800 μg/mL, the results showed that the latter concentrations was more potent at cell inhibition but when incubated with VEGF and ET‐1, the 200 μg/mL +ET‐1 was more potent at 24 hours. After 48 hours, 200μg/mL alone was more potent than the 800 μg/mL but in the presence of the mitogens, the effects of the plant extract at both concentrations were significantly different from the control and in this case caused significant proliferation. There was no significant difference between all the groups. Conclusion The result showed that the MLECO alone caused marked inhibition of HT29 cell lines after 72 hours but in the presence of the mitogens (VEGF and ET‐1), the effect on the cell line was that of proliferation showing that the mitogens interfered with the plant extract's ability to caused inhibition of cell line. Support or Funding Information Not applicable