No Magic Tomato? Study Breaks Link between Lycopene and Prostate Cancer Prevention
西紅柿預(yù)防前列腺癌的神話破滅
May 17, 2007
PHILADELPHIA -- Tomatoes might be nutritious and tasty, but don't count on them to prevent prostate cancer. In the May issue of Cancer Epidemiology, Biomarkers & Prevention, researchers based at the National Cancer Institute and Fred Hutchinson Cancer Research Center report that lycopene, an antioxidant predominately found in tomatoes, does not effectively prevent prostate cancer. In fact, the researchers noted an association between beta-carotene, an antioxidant related to lycopene, and an increased risk for aggressive prostate cancer.
費城——西紅柿雖然營養(yǎng)可口，但別指望它用來預(yù)防前列腺癌。來自美國國家癌癥研究所和佛瑞德·哈金森癌癥研究中心的研究人員在《癌癥流行病學(xué)、生物標(biāo)記物和預(yù)防》5月刊發(fā)表的報告指出，西紅柿中的主要抗氧化成分——番茄紅素，不能有效地預(yù)防前列腺癌。事實上，研究人員注意到，與番茄紅素有關(guān)的另一抗氧化成分β-胡蘿卜素，與增加前列腺癌轉(zhuǎn)移的風(fēng)險有關(guān)。
According to the researchers, the study is one of the largest to evaluate the role of blood concentrations of lycopene and other carotenoid antioxidants in preventing prostate cancer. Study data were derived from over 28,000 men enrolled in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, an ongoing, randomized National Cancer Institute trial to evaluate cancer screening methods and to investigate early markers of cancer.
據(jù)研究人員稱，該研究是評價血液中番茄紅素以及其它類胡蘿卜素抗氧化劑含量與預(yù)防前列腺癌關(guān)系的最大規(guī)模研究之一，研究數(shù)據(jù)來源于“前列腺癌、肺癌、結(jié)直腸癌和卵巢（PLCO）癌篩選試驗”登記入組的28000名男性患者，該試驗是國家癌癥研究所正在進行的一項評價癌癥篩選方法和癌癥早期標(biāo)記物研究的隨機試驗。
"It is disappointing, since lycopene might have offered a simple and inexpensive way to lower prostate cancer risk for men concerned about this common disease," said Ulrike Peters, Ph.D., M.P.H., of the Fred Hutchinson Cancer Research Center. "Unfortunately, this easy answer just does not work."
“令人失望，因為番茄紅素或許可以提供一種簡單而便宜的降低前列腺癌發(fā)病風(fēng)險的方法，遺憾的是，此路不通。” 佛瑞德·哈金森癌癥研究中心的Ulrike Peters博士說道。
Previous studies suggested that a diet rich in lycopene protected against prostate cancer, spurring commercial and public interest in the antioxidant. Antioxidants protect against free radicals, highly reactive atoms and molecules that can damage DNA and other important molecules in the cell. Since free radical damage increases with age, there has been a long-held suspicion in the scientific community that free radical damage could increase the risk of prostate cancer, a disease that has been clearly associated with age.
Subsequent studies of the potentially protective role of lycopene have been contradictory or inconclusive, according to Peters. In a 2006 study, she and her colleagues looked at the dietary intake of more than 25 tomato-based foods, also using data from the PLCO trial, and found no overall association between lycopene intake and prostate cancer.
先前的研究表明，富含番茄紅素的飲食可預(yù)防前列腺癌，這引起了商業(yè)和公眾對這種抗氧化劑的興趣。抗氧化劑可對抗自由基，自由基是高活性的原子或分子，可損傷細胞中的DNA和其它重要分子。由于自由基損傷隨齡增加，因此科學(xué)界曾長期懷疑，自由基損傷可能增加前列腺癌患病風(fēng)險，因為已經(jīng)非常明確，前列腺癌發(fā)病率與年齡有關(guān)。據(jù)Peters稱，后來有關(guān)番茄紅素可能的預(yù)防作用的研究結(jié)果或相互矛盾或不能肯定。她及其同事在2006年的研究中，考察了多于25種的西紅柿為主食物，并采用了PLCO試驗數(shù)據(jù)，發(fā)現(xiàn)從總體上看來，番茄紅素的攝入與前列腺癌不存在相關(guān)性。
In their current study, the researchers followed over 28,000 men between the ages of 55 and 74, enrolled in the PLCO Trial, with no history of prostate cancer. The men were initially screened through a PSA test and digital rectal exam, and were then followed through routine exams and screenings until first occurrence of prostate cancer, death or the end of the trial in 2001. At the beginning of the trial, the men gave a blood sample and completed a questionnaire related to their health, diet and lifestyle.
在此次研究中，他們跟蹤研究了28000多名年齡在55-74歲之間、無前列腺癌史的入組PLCO試驗的男性。他們最初采用PSA檢驗和直腸指診法進行篩查，此后進行常規(guī)檢查和篩查，直到首次查出前列腺癌、死亡或2001年試驗結(jié)束為止。在試驗開始時，受試者進行血樣分析和完成有關(guān)健康、飲食及生活方式的問卷調(diào)查。
The researchers focused on non-Hispanic Caucasian men, as the small number of cases among other ethnic groups was statistically insignificant. They found no significant difference between those who had prostate cancer and those who did not in relation to the concentration of lycopene in their bloodstream. "Our results do not offer support for the benefits of lycopene against prostate cancer," Peters said.
由于其他種族的少數(shù)病例缺少統(tǒng)計學(xué)意義，因此研究人員重點關(guān)注非西班牙裔白種男性。他們發(fā)現(xiàn)，前列腺癌患者與血液中番茄紅素濃度無關(guān)的人們之間無顯著性差異。“我們的結(jié)果對番茄紅素預(yù)防前列腺癌的益處不能提供支持。” Peters 說道。
Most surprisingly, says Peters, was the relationship between increased risk of aggressive prostate cancer - defined as disease that has spread beyond the prostate - and beta-carotene, another antioxidant found in many vegetables and commonly used as a dietary supplement.
This unexpected observation "may be due to chance, however beta carotene is already known to increase risk of lung cancer and cardiovascular disease in smokers," Peters said.
更為吃驚的是，前列腺癌的轉(zhuǎn)移風(fēng)險的提高與β-胡蘿卜素有關(guān)。β-胡蘿卜素是許多蔬菜中含有的另一種抗氧化劑，并常作為食品添加劑應(yīng)用。該意料之外的結(jié)果“或許事出偶然，但β-胡蘿卜素增加吸煙者肺癌和心血管疾病患病風(fēng)險，卻早已為人所知。” Peters說道。
"While it would be counter-productive to advise people against eating carrots and leafy vegetables, I would say to be cautious about taking beta carotene supplements, particularly at high doses, and consult a physician," Peters said.
“與其勸說人們拒絕食用胡蘿卜和葉類蔬菜會產(chǎn)生非建設(shè)性效果，我想說的是，服用β-胡蘿卜素添加劑，特別是大劑量服用時，應(yīng)該慎重，并咨詢醫(yī)生。”
Funding for this study was provided through the National Cancer Institute and the U.S. Department of Health and Human Services.
該研究由國家癌癥研究所和美國衛(wèi)生和公共福利部資助。

編譯：
西紅柿預(yù)防前列腺癌的神話破滅
據(jù)美國癌癥研究協(xié)會5月17日消息，西紅柿雖然營養(yǎng)可口，但別指望它用來預(yù)防前列腺癌。來自美國國家癌癥研究所和佛瑞德·哈金森癌癥研究中心的研究人員發(fā)表在《癌癥流行病學(xué)、生物標(biāo)記物和預(yù)防》5月刊的一篇報告指出，西紅柿中的主要抗氧化成分——番茄紅素，不能有效地預(yù)防前列腺癌。研究人員還觀察到，與番茄紅素有關(guān)的另一抗氧化成分β-胡蘿卜素，與增加前列腺癌轉(zhuǎn)移的風(fēng)險有關(guān)。
據(jù)研究人員稱，該研究是評價血液中番茄紅素以及其它類胡蘿卜素抗氧化劑含量與預(yù)防前列腺癌關(guān)系的最大規(guī)模研究之一，研究數(shù)據(jù)來源于“前列腺癌、肺癌、結(jié)直腸癌和卵巢癌（PLCO）篩選試驗”登記入組的28000名男性患者，該試驗是國家癌癥研究所正在進行的一項評價癌癥篩選方法和癌癥早期標(biāo)記物研究的隨機試驗。
先前的研究表明，富含番茄紅素的飲食可預(yù)防前列腺癌，這引起了商業(yè)和公眾對這種抗氧化劑的興趣?？寡趸瘎┛蓪棺杂苫?，自由基是高活性的原子或分子，可損傷細胞中的DNA和其它重要分子。由于自由基損傷隨齡增加，因此科學(xué)界曾長期懷疑，自由基損傷可能增加前列腺癌患病風(fēng)險，因為已經(jīng)非常明確，前列腺癌發(fā)病率與年齡有關(guān)。據(jù)Peters稱，后來有關(guān)番茄紅素可能的預(yù)防作用的研究結(jié)果或相互矛盾或不能肯定。她及其同事在2006年的研究中，考察了多于25種的西紅柿為主食品，并采用了PLCO試驗數(shù)據(jù)，發(fā)現(xiàn)從總體上看來，番茄紅素的攝入與前列腺癌不存在相關(guān)性。
在此次研究中，他們跟蹤研究了28000多名年齡在55-74歲之間、無前列腺癌史的入組PLCO試驗的男性。他們最初采用PSA檢驗和直腸指診法進行篩查，此后進行常規(guī)檢查和篩查，直到首次查出前列腺癌、死亡或2001年試驗結(jié)束為止。在試驗開始時，受試者進行血樣分析和完成有關(guān)健康、飲食及生活方式的問卷調(diào)查。由于其他種族的少數(shù)病例缺少統(tǒng)計學(xué)意義，因此研究人員重點關(guān)注非西班牙裔白種男性。結(jié)果他們發(fā)現(xiàn)，前列腺癌患者與血液中番茄紅素濃度無關(guān)的人們之間無顯著性差異。研究結(jié)果對番茄紅素預(yù)防前列腺癌的益處不能提供支持。更為吃驚的是，前列腺癌的轉(zhuǎn)移風(fēng)險的提高與β-胡蘿卜素有關(guān)。β-胡蘿卜素是許多蔬菜中含有的另一種抗氧化劑，并常作為食品添加劑應(yīng)用。
Peters稱，該意料之外的結(jié)果或許事出偶然，但β-胡蘿卜素增加吸煙者肺癌和心血管疾病患病風(fēng)險，卻早已為人所知。她提醒人們說，
服用β-胡蘿卜素添加劑，特別是大劑量服用時，應(yīng)該慎重，并咨詢醫(yī)生。
該研究由國家癌癥研究所和美國衛(wèi)生和公共福利部資助。