green tea extract – Oral Cancer News

Does green tea prevent cancer?

Source: www.ivanhoe.com Author: staff Evidence continues to brew about the protective effects of green tea against cancer, but scientists are still not sure the tea leaves reveal the answer. Vassiliki Papadimitrakopoulo, M.D., professor of medicine in the Department of Thoracic/Head and Neck Medical Oncology at the University of Texas M. D. Anderson Cancer Center, and colleagues tested 41 patients who took green tea extract orally for three months at three dose levels. Nearly 60 percent of patients with oral pre-malignant lesions, who were at the highest dose levels, displayed clinical response, compared with less than 20 percent among those taking placebo. Researchers also observed a trend toward improved histology, and a trend toward improvement in a handful of biomarkers that may be important in predicting cancer development. Patients were followed for 27.5 months, and at the end of the study period, 15 developed oral cancer. Although there was no difference in oral cancer development overall between those who took green tea extract and those who did not, patients who presented with mild to moderate dysplasia had a longer time to develop oral cancer if they took green tea extract. Although encouraged by the results, Dr. Papadimitrakopoulo cautioned against any recommendations that green tea could definitely prevent cancer. "This is a phase II study with a very limited number of patients who took what would be the equivalent of drinking eight to 10 cups of green tea every single day," Dr. Papadimitrakopoulo was quoted as saying. "We cannot with certainty claim [...]

Oral Cancer Foundation News Team - A2009-11-09T14:03:35-07:00November, 2009|Oral Cancer News|

Green tea shows promise as chemoprevention agent for oral cancer, M. D. Anderson study finds

Source: www.eurekalert.org Author: press release Green tea extract has shown promise as cancer prevention agent for oral cancer in patients with a pre-malignant condition known as oral leukoplakia, according to researchers at The University of Texas M. D. Anderson Cancer Center. The study, published online in Cancer Prevention Research, is the first to examine green tea as a chemopreventative agent in this high-risk patient population. The researchers found that more than half of the oral leukoplakia patients who took the extract had a clinical response. Long investigated in laboratory, epidemiological and clinical settings for several cancer types, green tea is rich in polyphenols, which have been known to inhibit carcinogenesis in preclinical models. Still, clinical results have been mixed. "While still very early, and not definitive proof that green tea is an effective preventive agent, these results certainly encourage more study for patients at highest risk for oral cancer," said Vassiliki Papadimitrakopoulou, M.D., professor in M. D. Anderson's Department of Thoracic/Head and Neck Medical Oncology, and the study's senior author. "The extract's lack of toxicity is attractive - in prevention trials, it's very important to remember that these are otherwise healthy individuals and we need to ensure that agents studied produce no harm." In the Phase II dose-finding study, 41 M. D. Anderson oral leukoplakia patients were randomized between August 2002 and March 2008 to receive either green tea extract or placebo. Participants took the extract, an oral agent, for three months at one of three doses - 500 per [...]

Oral Cancer Foundation News Team - A2009-11-05T13:05:14-07:00November, 2009|Oral Cancer News|

Marked inhibition of growth and invasive parameters of head and neck squamous carcinoma FaDu by a nutrient mixture

Source: ict.sagepub.com Author: M.W. Roomi, PhD et al. Head and neck squamous cell carcinomas (HNSCCs) are known for their aggressive growth and propensity to metastasize. The authors investigated the effect of a novel nutrient mixture (NM) containing ascorbic acid, lysine, proline, and green tea extract on human HNSCC cell line FaDu in vivo and in vitro. Athymic male nude mice (n = 12) were inoculated with 3 x 106 FaDu cells subcutaneously and randomly divided into 2 groups: group A was fed a regular diet and group B a regular diet supplemented with 0.5% NM. Four weeks later, the mice were sacrificed and their tumors were excised, weighted, and processed for histology. In vitro, FaDu cells were cultured in Dulbecco's modified Eagle's medium and exposed to NM at 0 to 1000 µg/mL in triplicate. Cell proliferation was assessed by MTT assay, matrix metalloproteinase (MMP) secretion by gelatinase zymography, invasion through Matrigel, apoptosis by live-green caspases, and cell morphology by hematoxylin—eosin staining. NM inhibited the growth of tumors by 55% (P = .0002) and exhibited dose-dependent toxicity on FaDu cells in vitro, with 53% (P = .0003) at 1000 µg/mL NM. Zymography revealed MMP-2 and phorbol 12-myristate 13-acetate—induced MMP-9 secretion. NM inhibited secretion of both MMPs in a dose-dependent manner, with virtual total inhibition at 1000 µg/mL. NM significantly inhibited FaDu invasion through Matrigel with total block at 1000 µg/mL. NM induced dose-dependent apoptosis. In conclusion, NM has therapeutic potential in the treatment of HNSCC by significantly suppressing tumor growth and [...]

Oral Cancer Foundation News Team - A2009-08-14T11:17:53-07:00August, 2009|Oral Cancer News|