石榴可以預防乳癌

一份在癌症防治研究期刊刊出的一項新的研究指出，食用石榴或飲用石榴汁可以預防雌激素反應乳癌(estrogen-responsive breast cancer)的發生。石榴中含有植物化合物鞣花丹寧(ellagitannins--ET)，在實驗室的試驗中可以抑制雌激素反應乳癌(estrogen-responsive breast cancer)的生長。在這些試驗中，鞣花丹寧抑制了芳香族酶(aromatase)而發揮作用，芳香族酶是身體用來製造雌激素的關鍵酵素，也在乳癌生長中扮演著關鍵角色。

研究人員研究了10種鞣花丹寧衍生物，包括了鞣花酸(ellagic acid)，沒食子酸(gallagic acid)，尿石素A 和 B(urolithins A and B)對抑制芳香族酶的活性和睾酮致乳腺腫瘤細胞增殖能力(testosterone-induced breast cancer cell proliferation)的影響。他們指出了6個可以抑制芳香族酶活性的鞣花丹寧衍生物，並指出尿石素B(urolithin B)在活體細胞裡最有效果。更進一步的分析並指出尿石素B有混合性的抑制能力，並有效的抑制了睪酮引起的乳癌細胞MCF-7aro 的增殖能力。MCF-7aro是一種乳癌細胞株(breast cancer cell line)，其細胞的增生是由睪酮(testosterone)的出現所引發的。其餘衍生物則都有抑制細胞增生的活性，只是比尿石素B還少罷了。

Pomegranates May Prevent Breast Cancer

DUARTE, Calif.—Eating pomegranates or drinking pomegranate juice may prevent estrogen-responsive breast cancers, says a new study published in Cancer Prevention Research (2009;3(1):108–13). The pomegranate fruit is a rich source of the phytochemicals ellagitannins (ET), which were shown inhibited the growth of estrogen-responsive breast cancer in laboratory tests. In these tests, ET inhibited aromatase, a key enzyme used by the body to make estrogen that also plays a key role in breast cancer growth.

Researchers studied a panel of 10 ET-derived compounds including ellagic acid, gallagic acid, and urolithins A and B for their ability to inhibit aromatase activity and testosterone-induced breast cancer cell proliferation. They identified six ET-derived compounds that inhibited aromatase activity, with urolithin B (UB) proving to be most effective in live cells. Further analysis of UB showed mixed inhibition, suggesting more than one inhibitory mechanism. UB also significantly inhibited testosterone-induced MCF-7aro cell proliferation. MCF-7aro is a breast cancer cell line that demonstrates increased cell proliferation in the presence of testosterone. The remaining test compounds also exhibited antiproliferative activity, but to a lesser degree than UB.