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Background: EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit), as one of the polycyclic group proteins (PcGs), is an epigenetic regulator that plays a crucial role in the pathophysiology of hematologic malignancies through regulating cell differentiation. Also, it is well known that aberrant expression of specific transcription factors can be involved in the pathogenesis of various cancers. Herein, we aimed to suppress EZH2 expression in MOLT-4 cells, T-ALL (T cell acute lymphoblastic leukemia) cell line, and evaluate the role of EZH2 on the expression of transcription factors that regulate T cell maturation, differentiation, and apoptosis. Methods: EZH2-siRNA was transfected into MOLT-4 cells, and the expression levels of EZH2, NOTCH1, TCF1, IKZF1, and NFATC1 were measured using real-time PCR. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay was performed to study the effect of EZH2 knockdown on MOLT-4 cell viability. The apoptosis rate of EZH2-siRNA transfected cells was assessed by flow cytometry. The interaction of mentioned genes was investigated using STRING and GO (gene ontology). Results: Our results have shown that EZH2-siRNA transfection can substantially decrease EZH2 expression in MOLT-4 cells. Besides, EZH2 suppression can upregulate NOTCH1, TCF1, IKZF1, and NFATC1 expression levels. EZH2 knockdown does not affect the viability and apoptosis of MOLT-4 cells. The most remarkable protein-protein interaction of EZH2 has been with NOTCH1. Besides, GO analysis has demonstrated that EZH2, NOTCH1, TCF1, IKZF1, and NFATC1 were located within nucleoplasm and can regulate RNA polymerase II-mediated transcription. Conclusion: MOLT-4 cells harbor increased expression of EZH2 in comparison with normal human T cells. EZH2 knockdown can upregulate the expression of the transcription factors involved in T cell differentiation. Thus, EZH2 can halt the differentiation of immature lymphoblastic T cells.

Purpose: Breast cancer is the most frequent malignancy diagnosed in women both in developed and developing countries. Natural products especially those from herbal origin have high potential in producing drug components with a source of novel structures. The present study was designed to explore the cytotoxic effects and the cell death mechanism of Scrophularia atropatana extracts. Methods: MTT assay was employed to evaluate the cytotoxic activity of the extracts of S. atropatana on the MCF-7 as well as non-malignant cells. Furthermore, induction of apoptosis was evaluated by TUNEL assay, cell death detection ELISA, DNA fragmentation test, western blotting and Real Time PCR. Results: In vitro exposures of the MCF-7 cells with different concentration of S. atropatana extract significantly inhibited their growth and viability and induced apoptosis in the MCF-7 cells. Cleavage PARP protein, decrease in the mRNA expression levels of bcl-2 and increase expression of Caspase-3 and Caspase-9 mRNA, highlights that the induction of apoptosis was the main mechanism of cell death. Moreover the expression study of Caspase-9 mRNA showed that, the extracts have induced apoptosis via intrinsic mitochondrial pathway. Conclusion: Our results demonstrated that dichloromethane extract of Scrophularia atropatana has an apoptotic effects and it can be developed as anticancer agents.

Cancer is uncontrolled growth of abnormal cells in the body. Nowadays, cancer is considered as a human tragedy and one of the most prevalent diseases in the wide, and its mortality resulting from cancer is being increased. It seems necessary to identify new strategies to prevent and treat such a deadly disease. Control survival and death of cancerous cell are important strategies in the management and therapy of cancer. Anticancer agents should kill the cancerous cell with the minimal side effect on normal cells that is possible through the induction of apoptosis. Apoptosis is known as programmed cell death in both normal and damaged tissues. This process includes some morphologically changes in cells such as rapid condensation and budding of the cell, formation of membrane-enclosed apoptotic bodies with well-preserved organelles. Induction of apoptosis is one of the most important markers of cytotoxic antitumor agents. Some natural compounds including plants induce apoptotic pathways that are blocked in cancer cells through various mechanisms in cancer cells. Multiple surveys reported that people with cancer commonly use herbs or herbal products. Vinca Alkaloids, Texans, podo phyllotoxin, Camptothecins have been clinically used as Plant derived anticancer agents. The present review summarizes the literature published so far regarding herbal medicine used as inducers of apoptosis in cancer.