Improved sensitization effect of sunitinib in cancer cells of the esophagus under hypoxic microenviroment.

Radiotherapy is widely used in esophageal squamous cell carcinoma (ESCC) treatment. Promoting the radiation sensitivity of cancer cells is required. Recent studies have shown that sunitinib can inhibit the growth of several cancer lines. However, few studies on the radiosensitive effect of sunitinib on ESCC cells under hypoxic conditions have been conducted. In the present study, the radiosensitive effects of sunitinib on human ESCC cells were assessed, and the underlying mechanisms were explored. ESCC cells were exposed to hypoxia and treated with sunitinib at different concentrations prior to irradiation. Sunitinib potently inhibited ESCC cell proliferation in an MTT assay. In a clonogenic survival assay, sunitinib sensitized hypoxic ESCC cells to radiation, with sensitizing enhancement ratios of 1.31-1.59. In addition, sunitinib promoted the apoptosis of ESCC cells, but did not alter their cell cycle distribution. Radiosensitization was accompanied by inhibition of the radiation-induced upregulation of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) expression. Thus, sunitinib confers radiosensitivity to esophageal cancer cells, which is associated with the downregulation of HIF-1α and VEGF expression. Sunitinib can be a promising radiosensitizer for esophageal cancer radiotherapy.

[The prevalence of mild cognitive impairment among residents aged 55 or over in Chengdu area].

OBJECTIVE: To study the prevalence of mild cognitive impairment (MCI) in the urban and the rural areas in Chengdu, Southwest China. METHODS: Residents aged 55 or over were selected by stratified random cluster sampling from 19 districts, cities, and counties of Chengdu area in Sichuan province. A two-stage survey was carried out. In the first stage, CMMSE, CES-D were used as screening instruments. In the second stage, Diagnostic questionnaires of dementia and CDR were used as diagnostic instruments. The diagnostic criteria of mild cognitive impairment adopted from Petersen's were: (1) memory complaint; (2) normal activities of daily living; (3) normal general cognitive function; (4) memory impairment incompatible with age; (5) not demented; (6) CDR = 0.5 and (7) exclusion of the reversible cognitive impairment caused by other factors (i.e. depression). RESULTS: Three thousand, nine hundred and ten subjects were examined. The prevalence rates of MCI was 2.4%. The MCI prevalence rates in the urban and the rural areas were 1.5%, 2.5% respectively, without significant difference. The MCI prevalence in males and females were 1.8%, 2.9% respectively. Prevalence rate in female was higher than in males with significant difference. Prevalence of illiteracy (4.0%) was the highest among different educational levels. The accumulated prevalence increased with age. CONCLUSION: The prevalence of MCI (2.4%) was slightly higher than the prevalence of AD (2.05%) in the same areas of Chengdu. MCI seemed to be a high risk factor for AD which should to be followed up. Early intervention in MCI might be helpful in the prevention of AD.