Tualang honey inhibits cell proliferation and promotes apoptosis of human lung adenocarcinoma cells via apoptosis signaling pathway

Abstract Introduction Tualang honey (TH) has been shown to have anticancer properties for breast, cervical, leukaemia, oral squamous, and bone cancers. This study was aimed at investigating the anti-proliferative and apoptosis effect of TH on human lung adenocarcinoma (ADC) cells. Methods MTT assay was used to detect the anti-proliferative effect of TH in ADC (H23 and A549) cells. Morphological changes of cells treated with TH were observed under phase-contrast and fluorescence microscopy. Flow cytometry was carried out to evaluate cell cycle progression. Annexin V-FITC assay was performed to investigate the effects of TH on the apoptosis of ADC cells. Apoptosis protein profile was detected using Human Apoptosis Antibody Array. Results MTT assay indicated that TH inhibited the proliferation of ADC cells in a dose-and time-dependent manner. The ADC cells treated with TH showed typical apoptotic features such as membrane blebbing, cell shrinkage, chromatin condensation and fragmented nucleus. The cell cycle analysis revealed the accumulation of TH treated ADC cells in sub-G1 and G2/M phases. Annexin V-FITC assay provided the evidence for apoptosis induction by TH. Apoptosis profiling array indicated that TH up-regulated the expression of caspases (caspase-3 and -8), pro-apoptotic (Bid, Bax, cytochrome c, SMAC), cell-surface death receptor (Fas), cell cycle regulator (p21) and tumor suppressor (p53), as well as down-regulating the expression of 2 anti-apoptotic proteins (Bcl-2 and Bcl-w) in ADC cells. Conclusion The present study suggests TH as a potential anti-cancer agent, following its capacity to promote the growth inhibition and apoptosis of ADC cells via apoptosis signaling pathways.