ABSTRACT
Objective:To explore the effects of hypoxia-inducible factor 2α genes on under hypoxia on proliferation,apoptosis, cell cycle distribution and migration of invasiveness of human hepatocellular carcinoma cell HepG2.Methods: Human hepatoma cell line HepG2 induced by cobalt chloride (CoCl2) was selected as the research object,construction of siRNA specific carrier HIF-2α, transfection of HepG2 cells under hypoxia.Real-time PCR,Western blot method in the detection of before and after transfection in each group of HIF-2α mRNA and protein expression;MTT method to detect the proliferation of HepG2 cells before and after transfection;apoptosis rate and distribution of cell cycle of HepG2 cells before and after transfection were detected by flow cytometry;Transwell test was used to detect the invasion and migration ability of HepG2 cells before and after transfection.Results: Under hypoxia,significant increased HIF-2α expression in hepatocellular carcinoma HepG2 cells.Specific transfection of HIF-2α siRNA in HepG2 cells after HIF-2α mRNA and protein expression levels were significantly inhibit cell proliferation decreased,apoptosis rate increased in the ratio of G0/G1 phase cells increased synthesis phase (S) and late (G2/M) synthesis cell ratio decreased,which in vitro invasion and migration of cells was inhibited.Conclusion:Expression of HIF-2α increases in hepatocellular carcinoma HepG2 cells under hypoxia. Specific siRNA can be cut by HIF-2α gene expression in HepG2 cells under hypoxia,to inhibit HepG2 cell proliferation,invasion, migration,and change the distribution of cell cycle and induce its apoptosis.
ABSTRACT
Hypoxia and hypoxia-induced factors (HIFs) are main regulators for tumor stem cells, metastasis-initiating cells and their differentiated progenies to adapt to the environment which lacks oxygen and nutrient in the process of cancer development. HIFs are up-regulated in many tumors, including leukemia, glioblastoma, melanoma, prostate cancer, breast cancer and pancreatic cancer, in where they are especially highly expressed in hypoxic regions. HIFs activation can induce expression of numerous stem cell related genes and multidrug resistance genes, which may play important roles in tumour and stem cell-mediated self-renewing, energy metabolism alternation, invasion, metastasis, angiogenesis and treatment resis?tance of neoplastic cells. Consequently, it will provide new clues for cancer therapy after investigating the role of HIFs in tar?geted regulation and metabolic pathway modulation in various stem cell-mediated tumor cells.
ABSTRACT
Transient global amnesia (TGA) is a disease with dramatic manifestations. It is often induced by the physical or psychogenic factors, and is characterized by a sudden onset of anterograde amnesia accompanied by repeated asking of questions, lasting for minutes or hours. The study of TGA mainly focused on the aspects of etiological and pathological mecha-nisms. Currently, there are several following hypotheses: Transient ischemic attack, epilepsy,migraine, cerebral venous ischemia or venous embolism, personality disorder or emotional stimulation. The prognosis of TGA is better with low recurrence rate. No specific treatment is needed. This article reviews the advances in research on TGA.
ABSTRACT
Atrial fibrillation is the most common arrhythmia disease in the clinical works,and endangers the public health seriously.With the development of AAD and ABL,we have made a great progress in AF's prevention and treatment.However,the literature and research about the non-disease causes of lone AF are very rare.So,the article will make a system review and summary about it,in order to instruct the lone AF's primary prevention.