Elevated fat and cholesterol levels found in a typical American-style diet plays an importantrole in the growth and spread of prostate cancer , say researchers at Thomas Jefferson University's Kimmel CancerCenter. Their study, the first to show such an association, is published inthe December issue of The American Journal of Pathology. Itdemonstrates how mice eating a Western diet, and predisposed todevelop prostate cancer, can develop larger tumors that are fastergrowing and metastasize more easily to the lungs, compared toanimals eating a control diet. In this study, a research team led by Philippe G.
Frank, Ph.D.,assistant professor in the Department of Stem Cell Biology andRegenerative Medicine at Jefferson, tried to understand whyprostate cancer incidence is low in Asian countries, butsignificantly increases in Asian men who move to the United States."Our hypothesis is that environmental factors, most likely presentin the diet, may act as late stage promoters, responsible for thetransformation of a prostate tumor from an early stage form into amore aggressive and clinically-apparent form," says Dr. Frank. Dietary fat and cholesterol have been shown to be risk factors inthe development and progression of other tumor types, butdiet-based studies in prostate cancer patients have reachedcontradictory conclusions, Dr. Frank says. For this reason, he andhis colleagues turned to the TRAMP transgenic mouse model todetermine the role of dietary fat and cholesterol.
This mouse modelis believed to closely parallel the pathogenesis of human prostatecancer. TRAMP mice were placed on a diet that contained 21.2 percent fatand 0.2 percent cholesterol, reflective of a typical Western diet.A control group of TRAMP mice was fed a normal chow that had 4.5percent fat and negligible amounts of cholesterol. They found that the Western diet accelerated prostate tumordevelopment and progression. These tumors also produced increasedlevels of receptors that bind to lipoproteins carriers ofcholesterol, and they were more aggressive. The researchers furtherdiscovered that the TRAMP mice fed a Western diet appeared toexperience greater incidence of cancer metastasis to the lungs, compared to the control group. Launching Gantry Crane
The research team also noted that TRAMP mice fed the high fat/highcholesterol chow had less cholesterol in their blood compared tocontrol mice fed the same diet. "This likely reflects the fact thattheir tumors depend on cholesterol to grow," explains Dr. Frank."This study suggests that monitoring cholesterol levels in men atrisk, diagnosed, or treated for prostate cancer may help limitcancer growth or even recurrence." Dr. Frank says the evidence involving cholesterol is strong - afinding he believes makes sense physiologically. Gantry Crane Manufacturer
"Cells needcholesterol to produce androgen hormones, and androgen hormonespromote prostate cancer growth," he explains. "Perhaps moreimportantly, we also believe that tumors feed on cholesterol, andthe more blood cholesterol is accessible, the more is available fortumor growth. "Although this is a mouse study, numerous studies have shown thehealth benefits of controlling blood cholesterol levels and fatintake. This research suggests the same advice may offer somebenefit for men at risk of developing prostate cancer or evendiagnosed with prostate cancer," says Dr. Frank. Manual Chain Hoist Manufacturer
He adds statins that lower cellular cholesterol production may beone way to reduce prostate cancer progression - although that hasyet to be demonstrated. Monitoring blood cholesterol levels ofprostate cancer patients may also provide important informationabout cancer progression. "For example, tests showing a sudden dropin blood cholesterol is often indicative of the development oftumors," Dr. Frank adds.
Dr. Frank receives funding from the Jane Barsumian/Mary Lyons Trustand the Susan G. Komen Foundation; the first author, GemmaLlaverias Ph.D., was supported by the Spanish Ministry of Scienceand Innovation. The other study co-authors are Christiane Danilo,M.S., Yu Wang, M.S., Agnes Witkiewicz, M.D., Kristin Daumer, M.S.,and Michael Lisanti, M.D., Ph.D. All researchers are from Thomas Jefferson University, areaffiliated with the Kimmel Cancer Center, and declare no conflictsof interest.
Source: Thomas Jefferson University Additional References Citations.
Frank, Ph.D.,assistant professor in the Department of Stem Cell Biology andRegenerative Medicine at Jefferson, tried to understand whyprostate cancer incidence is low in Asian countries, butsignificantly increases in Asian men who move to the United States."Our hypothesis is that environmental factors, most likely presentin the diet, may act as late stage promoters, responsible for thetransformation of a prostate tumor from an early stage form into amore aggressive and clinically-apparent form," says Dr. Frank. Dietary fat and cholesterol have been shown to be risk factors inthe development and progression of other tumor types, butdiet-based studies in prostate cancer patients have reachedcontradictory conclusions, Dr. Frank says. For this reason, he andhis colleagues turned to the TRAMP transgenic mouse model todetermine the role of dietary fat and cholesterol.
This mouse modelis believed to closely parallel the pathogenesis of human prostatecancer. TRAMP mice were placed on a diet that contained 21.2 percent fatand 0.2 percent cholesterol, reflective of a typical Western diet.A control group of TRAMP mice was fed a normal chow that had 4.5percent fat and negligible amounts of cholesterol. They found that the Western diet accelerated prostate tumordevelopment and progression. These tumors also produced increasedlevels of receptors that bind to lipoproteins carriers ofcholesterol, and they were more aggressive. The researchers furtherdiscovered that the TRAMP mice fed a Western diet appeared toexperience greater incidence of cancer metastasis to the lungs, compared to the control group. Launching Gantry Crane
The research team also noted that TRAMP mice fed the high fat/highcholesterol chow had less cholesterol in their blood compared tocontrol mice fed the same diet. "This likely reflects the fact thattheir tumors depend on cholesterol to grow," explains Dr. Frank."This study suggests that monitoring cholesterol levels in men atrisk, diagnosed, or treated for prostate cancer may help limitcancer growth or even recurrence." Dr. Frank says the evidence involving cholesterol is strong - afinding he believes makes sense physiologically. Gantry Crane Manufacturer
"Cells needcholesterol to produce androgen hormones, and androgen hormonespromote prostate cancer growth," he explains. "Perhaps moreimportantly, we also believe that tumors feed on cholesterol, andthe more blood cholesterol is accessible, the more is available fortumor growth. "Although this is a mouse study, numerous studies have shown thehealth benefits of controlling blood cholesterol levels and fatintake. This research suggests the same advice may offer somebenefit for men at risk of developing prostate cancer or evendiagnosed with prostate cancer," says Dr. Frank. Manual Chain Hoist Manufacturer
He adds statins that lower cellular cholesterol production may beone way to reduce prostate cancer progression - although that hasyet to be demonstrated. Monitoring blood cholesterol levels ofprostate cancer patients may also provide important informationabout cancer progression. "For example, tests showing a sudden dropin blood cholesterol is often indicative of the development oftumors," Dr. Frank adds.
Dr. Frank receives funding from the Jane Barsumian/Mary Lyons Trustand the Susan G. Komen Foundation; the first author, GemmaLlaverias Ph.D., was supported by the Spanish Ministry of Scienceand Innovation. The other study co-authors are Christiane Danilo,M.S., Yu Wang, M.S., Agnes Witkiewicz, M.D., Kristin Daumer, M.S.,and Michael Lisanti, M.D., Ph.D. All researchers are from Thomas Jefferson University, areaffiliated with the Kimmel Cancer Center, and declare no conflictsof interest.
Source: Thomas Jefferson University Additional References Citations.