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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.

We have previously demonstrated in an in vitro study that Snail increased the invasion activity of hepatoma cells by upregulating matrix metalloproteinase (MMP) gene expression. In the present study, we examined whether Snail gene expression correlates with cancer invasion and prognosis of patients with hepatocellular carcinoma (HCC). Quantitative reverse transcription -polymerase chain reaction (RT -PCR) was performed to evaluate Snail, E-cadherin, and MMP mRNA expressions in eight nodule-in-nodule tumours and 47 ordinary HCC tissues. In the nodule-in-nodule tumours, Snail expression significantly increased with tumour dedifferentiation (P ¼ 0.047). In the ordinary HCC tissues, Snail expression was significantly correlated with portal vein invasion (P ¼ 0.035) and intrahepatic metastasis (P ¼ 0.050); it also showed a significant correlation with MT1-MMP expression (r ¼ 0.572, Po0.001). In recurrence-free survival, the group with high Snail expression showed significantly poorer prognosis (P ¼ 0.035). Moreover, high Snail expression was an independent risk factor for early recurrence after curative resection. During the progression of HCC, Snail expression may be induced and accelerate invasion activity by upregulating MMP expression, resulting in portal invasion, intrahepatic metastasis, and poor prognosis. British Journal of Cancer (2005) Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies in the world and a frequent cause of cancer fatalities in Japan. Improvements in early diagnosis, surgical techniques, and perioperative management have contributed to decreases in mortality and morbidity among patients with HCC (Okuda et al, 1985;Fran et al, 1999). However, the long-term prognosis of patients with HCC after hepatectomy has been still poor because of a high incidence of recurrence after initial treatment (Fong et al, 1999;Poon et al, 2000b). Several centres have reported a cumulative 5-year recurrence rate ranging from 75 to 100% (Chen et al, 1994;Fong et al, 1999;Poon et al, 2000b). Pathological and genetic analyses have indicated two features in HCC recurrence: multicentric occurrence of new tumours (MO) and intrahepatic metastasis of the original tumour (im) (Tsuda et al, 1992;Matsumoto et al, 2001). It has been reported that MO is significantly influenced by the underlying liver status, such as the presence of active hepatitis (Belghiti et al, 1991;Ko et al, 1996). On the other hand, im is thought to be more closely associated with tumour factors, especially portal vein invasion (vp) (Vauthey et al, 1995;Shimada et al, 1999). Several published studies have demonstrated that vp plays an important role in the im process and influences the survival rate of patients with HCC (Fuster et al, 1996;Mitsunobu et al, 1996; The Liver Cancer Study Group of Japan, 1994). Therefore, it is important to elucidate the molecular mechanisms of vp and im; the subsequent establishment of markers for predicting vp and im may contribute to improvement in the prognosis of patients with HCC.Recently, the z...

In the normal human life span, there occur lifestyle-related diseases that may be preventable with nontoxic agents. This paper deals with the preventive activity of green tea in some lifestyle-related diseases. Green tea is one of the most practical cancer preventives, as we have shown in various in vitro and in vivo experiments, along with epidemiological studies. Among various biological effects of green tea, we have focused on its inhibitory effect on TNF-␣ gene expression mediated through inhibition of NF-B and AP-1 activation. Based on our recent results with TNF-␣-deficient mice, TNF-␣ is an endogenous tumor promoter. TNF-␣ is also known to be a central mediator in chronic inflammatory diseases such as rheumatoid arthritis and multiple sclerosis. We therefore hypothesized that green tea might be a preventive agent for chronic inflammatory diseases. To test this hypothesis, TNF-␣ transgenic mice, which overexpress TNF-␣ only in the lungs, were examined. The TNF-␣ transgenic mouse is an animal model of human idiopathic pulmonary fibrosis which also frequently develops lung cancer. Expressions of TNF-␣ and IL-6 were inhibited in the lungs of these mice after treatment with green tea in drinking water for 4 months. In addition, judging from the results of a prospective cohort study in Saitama Prefecture, Japan, green tea helps to prevent cardiovascular disease. In this study, a decreased relative risk of death from cardiovascular disease was found for people consuming over 10 cups of green tea a day, and green tea also had life-prolonging effects on cumulative survival. These data suggest that green tea has preventive effects on both chronic inflammatory diseases and lifestyle-related diseases (including cardiovascular disease and cancer), resulting in prolongation of life span.

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