高浓度的维生素D有助于身体产生抗肿瘤的蛋白质

大壮

人类的肺肿瘤会破坏抗癌激素-维生素D
http://www.sciencedaily.com/releases/2009/04/090420151223.htm

美国科学日报（ScienceDaily）（2009年4月24日）--匹兹堡大学癌症研究所（UPCI）的一项新研究表明：人类的肺肿瘤会消除维生素D--一种抗癌激素。
匹兹堡大学癌症研究所药理学和生化学部的助理研究教授、主要研究者Pamela Hershberger博士解释说：“高浓度的维生素D有助于身体产生抗肿瘤的蛋白质”。 “我们发现肺癌细胞会产生一种叫做CYP24的酶，这种酶可以对抗维生素D的抗癌效果。为了更好地研究这种现象，我们开发了一种无放射性的试验，来测量人体组织和血液中维生素D的含量。”
Hershberger博士认为这种试验非常灵敏，具有临床潜力。她说“我们希望这种新试验将有助于确定使组织中的维生素D维持治疗浓度的最佳方法”。
肺癌是美国癌症死亡的主要原因，每年造成16万美国人死亡，是最难治疗的癌症之一。其五年存活率很低，迫切需要更好的治疗方法。Hershberger博士认为，总有一天维生素D会被用做提高疗效的一种化学预防药剂。
本研究结果(摘要编号2402)将在丹佛4月18日到22日举行的美国癌症研究协会（AACR）第100届年会上宣读。
该研究得到了匹兹堡大学癌症研究所的肺癌专业杰出研究计划的支持。

改编自美国科学促进会的一个部门（University of Pittsburgh Schools of the Health Sciences）通过EurekAlert!提供的材料。
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Human Lung Tumors Destroy Anti-cancer Hormone Vitamin D
http://www.sciencedaily.com/releases/2009/04/090420151223.htm

Science Daily (Apr. 24, 2009) — Human lung tumors have the ability to eliminate Vitamin D, a hormone with anti-cancer activity, a new study from the University of Pittsburgh Cancer Institute (UPCI) suggests.
"High levels of Vitamin D help the body produce proteins with anti-tumor activity," explained principal investigator Pamela Hershberger, Ph.D., a research assistant professor in UPCI's Department of Pharmacology and Chemical Biology. "We've discovered that lung cancer cells make an enzyme called CYP24, which counteracts the positive effects of Vitamin D. To better study it, we developed the first radioactive-free assay that measures the amount of Vitamin D in tissues and blood."
According to Dr. Hershberger, this test is sensitive enough to have clinical potential. "We hope this new assay will help identify the best approaches to maintain therapeutic levels of Vitamin D in tissues," she said.
Lung cancer is the leading cause of cancer death in the United States in both men and women, killing 160,000 people annually, and remains one of the most difficult cancers to treat. The five-year survival rate remains low, and better treatments are much needed. According to Dr. Hershberger, it is possible that one day Vitamin D could be used as a chemopreventive agent to improve patient outcomes.
Results of the study, Abstract Number 2402, are being presented at the 100th annual meeting of the American Association for Cancer Research (AACR), April 18 to 22, in Denver.
This study was supported by UPCI's Lung Cancer Specialized Program of Research Excellence.