No abstract

Hypoxia-inducible factor-1 (HIF-1) is a pivotal factor that regulates cellular responses to hypoxia and is presumably linked to regulation of angiogenesis and tumor growth. We assessed the difference in transcription activity of two HIF-1alpha polymorphic variants (P582S and A588T), along with molecular epidemiological study among head and neck squamous cell carcinoma (HNSCC) patients. Both HIF-1alpha variants revealed significantly higher transcription activity than wild-type (WT) did, under normoxic and hypoxic conditions (P < 0.02). Furthermore, tumors from HNSCC patients with heterozygous alleles having P582S or A588T had significantly increased numbers of microvessels compared with those with homozygous WT (P = 0.02). In addition, all patients with tumors of T1 (below 2 cm diameter) were WT, while 14 of 47 patients with tumors of > or =T2 were heterozygous. The elevated transactivation capacity of variant forms of HIF-1alpha implies a role of HIF-1alpha polymorphisms in generating individually different tumor progression.

The significance of drinking green tea in prevention of two of the main lifestyle-related diseases, cancer and cardiovascular disease, was demonstrated in terms of a prospective cohort study on a total of 8,552 general residents in Saitama Prefecture, Japan. On the basis of the follow-up study, we revealed decreased relative risk of cancer incidence for those consuming over 10 cups a day, compared with those consuming below 3 cups: 0.54 (95% confidence interval, 0.22-1.34) for men, 0.57 (0.34-0.98) for women, and 0.59 (0.35-0.98) for both sexes. Furthermore, a significant delay in cancer onset was associated with increased consumption of green tea. Next, decreased relative risk of death from cardiovascular disease was 0.58 (0.34-0.99) for men, 0.82 (0.49-1.38) for women, and 0.72 (0.60-1.04) for members of both sexes consuming over 10 cups a day. Finally, we evaluated the life-prolonging effects of drinking green tea on cumulative survival, using the life table.

A good correlation was observed between enhanced lung cancer risk and restriction fragment length polymorphisms (RFLPs) of the P450IAl gene with the restriction enzyme. MspI. Genotype frequencies of 0.49 for the predominant homozygote, 0.40 for the heterozygote, and 0.11 for the homozygous rare allele were observed in a healthy population. Among lung cancer patients, the frequency of homozygous rare allele of P450IAl gene was found to be about 3-fold higher than that among healthy population, and this difference was statistically significant. This is the first report to identify the genetically high risk individuals to lung cancer at the gene level.

Objective-To investigate the association between consumption ofgreen tea and various serum markers in a Japanese population, with special reference to preventive effects of green tea against cardiovascular disease and disorders ofthe liver.Design-Cross sectional study. Setting-Yoshimi, Japan. Subjects-1371 men aged over 40 years resident in Yoshimi and surveyed on their living habits including daily consumption of green tea. Their peripheral blood samples were subjected to several biochemical assays.Results-Increased consumption of green tea was associated with decreased serum concentrations of total cholesterol (P for trend <0.001) and triglyceride (P for trend=0.02) and an increased proportion of high density lipoprotein cholesterol together with a decreased proportion oflow and very low lipoprotein cholesterols (P for trend=0-02), which resulted in a decreased atherogenic index (P for trend=0.02). Moreover, increased consumption of green tea, especially more than 10 cups a day, was related to decreased concentrations of hepatological markers in serum, aspartate aminotransferase (P for trend=0.06), alanine transferase (P for trend=0.07), and ferritin (P for trend=0002).