Effects of EGCG on proliferation and apoptosis of gastric cancer SGC7901 cells via down-regulation of HIF-1α and VEGF under a hypoxic state.

OBJECTIVE: To investigate the effects of epigallocatechin-3-gallate (EGCG) on proliferation and apoptosis of human gastric cancer SGC7901 cells under a hypoxic state. MATERIALS AND METHODS: Human gastric cancer SGC7901 cells were sub-cultured, and the cobalt chloride (CoCl2) hypoxia model was established. The blank control group (normoxia group), hypoxia control group (hypoxia group) and hypoxia + different concentrations of EGCG subgroups (20, 40, 60, 80, 100 µg/mL EGCG) were set up. Cell viability was detected via methyl thiazolyl tetrazolium (MTT) assay, apoptosis was detected via flow cytometry, and expressions of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were detected via reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. RESULTS: Relatively low concentrations of EGCG (20-80 µg/mL) presented no significant inhibiting effect on SGC7901 cell growth within a short time (24 h) (p>0.05). The increasing concentration of EGCG inhibited cell proliferation under a hypoxia state (p<0.05). EGCG induced apoptosis in a dose-dependent manner under hypoxia (p<0.05). EGCG could significantly impede expressions of HIF-1α and VEGF proteins (p<0.05), and down-regulate the level of VEGF mRNA (p<0.05), but it showed no significant effect on the HIF-1α mRNA expression (p>0.05). CONCLUSIONS: EGCG inhibited cell proliferation under hypoxia via the downregulation of HIF-1α and its downstream target gene VEGF levels, providing a theoretical basis for the early diagnosis and treatment of gastric cancer in clinic.

Cardiac sarcoidosis: a potentially fatal but treatable form of infiltrative heart disease.

Cardiac sarcoidosis is a rare but important differential diagnosis in patients who present with progressive heart failure and arrhythmia. It may be diagnosed on endomyocardial biopsy. An excellent response can be achieved with steroid therapy in the early acute inflammatory stage. Progression of the disease may lead to end-stage heart failure that requires implantation of a permanent pacemaker, implantable cardioverter-defibrillator, or mechanical circulatory support as a bridge to heart transplantation. We present three Hong Kong Chinese patients with cardiac sarcoidosis.

Radical-mediated diastereoselective construction of a chiral synthon for synthesis of dolabellanes.

[reaction: see text] A useful trans-substituted multifunctional cyclopentane with a chiral quaternary center was selectively synthesized by free radical Michael addition to the (Z)-propionate or -malonate derivatives. The stereoselectivity could be reversed by changing the configuration of the double bond.

Injection of vasodilators into arterial grafts through cardiac catheter to relieve spasm.

Both native coronary artery and coronary bypass grafts may develop vasospasm after coronary artery bypass grafting. We recommend that whenever there is a high suspicion of vasospasm in arterial grafts and the native coronary artery unresponsive to or not suitable for usual vasodilator therapy, prompt selective graft arteriogram should be performed. Intraluminal injection of vasodilators such as calcium antagonists in combination with nitroglycerin may provide an effective antispastic therapy and this procedure could be lifesaving as demonstrated in the present report.

Combined atrial septostomy and oral sildenafil for severe right ventricular failure due to primary pulmonary hypertension.

Management of primary pulmonary hypertension is usually difficult because the disease is uncommon and the aetiology of the disease is not well understood. The disease is potentially lethal because it can lead to failure of the right ventricle, low cardiac output, and ensuing multiple organ failure. We report the successful treatment of a case of low-output syndrome due to primary pulmonary hypertension using combined drug therapy and atrial septostomy. Latest developments in the treatment of this disease are also discussed.