The influence of certain plant substances and their chemopreventive activity in ovarian cancer

Bixin Triggers Apoptosis of Human Hep3B Hepatocellular Carcinoma Cells: An Insight to Molecular and IN SILICO Approach

Hepatocellular carcinoma (HCC) is the most common liver cancer and is known to be resistant to conventional chemotherapy. The use of herbal medicine and supplements has increased over recent decades following side effects and resistant to conventional chemotherapy. The seeds of Bixa orellana L. commonly known as annatto have recently gained scientific attention due to presence of a carotenoid bixin for its substantial anticancer properties. However, molecular mechanisms underlying bixin-induced apoptosis are still unclear. Treatment of bixin significantly decreased the number of Hep3B cells and morphological study revealed the change in cellular and nuclear morphology that trigger the events of apoptosis confirmed by annexin V/PI staining. Further DCFDA and rhodamine 123 spectrofluorimetry study showed elevation in reactive oxygen species (ROS) production and loss of mitochondrial membrane potential (MMP), respectively. ROS production caused DNA damage and apoptosis was marked by cell cycle arrest, up-regulation of Bax and FasL protein as well as cleavage of caspase-9, caspase-8 and caspase-3 protein. Docking study with pro-apoptotic molecule Bax and surface Fas ligand exhibited energetically favourable binding interaction. Collectively, these results suggest that bixin capable of modulating the extrinsic and intrinsic molecules of apoptosis indicating its potential for development of promising candidate for hepatocellular carcinoma.

Triptolide inhibits the proliferation and migration of medulloblastoma Daoy cells by upregulation of microRNA-138

Medulloblastoma is a primitive neuroectodermal-derived brain tumor and the most common malignant brain tumor in children. Triptolide (TPL) is the major active component extracted from Tripterygium wilfordii Hook F. This study aimed to explore the effects of TPL on medulloblastoma cell proliferation, migration, and apoptosis, as well as the underlying possible molecular mechanism. Viability, proliferation, and apoptosis of Daoy cells were measured using cell counting kit-8 assay, 5-bromo-2'-deoxyuridine incorporation assay, and Guava Nexin assay, respectively. Cell migration was detected using two-chamber transwell assay and wound healing assay. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to determine the relative expression of microRNA-138 (miR-138) in Daoy cells. Cell transfection was used to change the expression of miR-138 in cells. Western blot analysis was used to analyze the expression of key factors involved in cell apoptosis, cell migration, the phosphatidylinositol 3-kinase (PI3K)/protein kinase 3 (AKT) pathway, and the Notch pathway in Daoy cells. We found that TPL significantly inhibited the viability, proliferation, and migration of Daoy cells but promoted Daoy cell apoptosis. The expression levels of matrix metalloproteinases (MMP)-2 and MMP-9 after TPL treatment were decreased. The expression of miR-138 in Daoy cells after TPL treatment was increased. Suppression of miR-138 obviously reversed the TPL-induced Daoy cell proliferation, migration inhibition, and cell apoptosis enhancement, as well as the inactivation of the PI3K/AKT and Notch pathways. Cyclin-dependent kinase 6 (CDK6) was a direct target gene of miR-138, which might be involved in the antitumor effects of TPL on Daoy cells. In conclusion, our study verified that TPL exerted anticancer effects on medulloblastoma cells possibly via upregulating miR-138 and inactivating the PI3K/AKT and Notch pathways.