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07-15-2005, 07:07 PM

Here you go, Al

Abstract
Nutrition and Cancer
2000, Vol. 38, No. 1, Pages 123-130
(doi:10.1207/S15327914NC381_17)

Molecular Mechanisms of Cell Cycle Block by Methionine Restriction in Human Prostate Cancer Cells

Shan Lu, Daniel E. Epner*

Previous studies have shown that dietary or pharmacological methionine restriction inhibits growth of human prostate cancer cells in vitro or as xenografts in mice. We undertook the present studies to clarify the molecular mechanisms by which methionine restriction inhibits prostate cancer cell growth. We found that PC-3 and DU 145 cells stopped proliferating within six days in growth medium containing homocysteine in place of methionine. In contrast, proliferation of LNCaP cells was only partially inhibited by the absence of methionine. Using flow cytometry, we found that methionine restriction caused PC-3 cells to arrest in all phases of the cell cycle, but predominantly in the G2/M phase, whereas LNCaP cells accumulated exclusively in the G1 phase. Methionine restriction led to accumulation of the cyclin-dependent kinase inhibitors p21 and p27, as determined by Western blot analysis, and inhibited the enzymatic activities of the cyclin-dependent kinases CDK2 and cdc2, as determined by an in vitro kinase assay. However, methionine restriction had little or no effect on CDK2 or cdc2 protein levels. Methionine restriction also induced PC-3 cells to undergo apoptosis, as indicated by the appearance of a typical nucleosomal ladder on gel electrophoresis of genomic DNA. We conclude that methionine restriction has potential as a novel treatment strategy for prostate cancer.

Cited by
Ya-Min Fu, Zu-Xi Yu, Yi-Qi Li, Xiaokang Ge, Phillip J. Sanchez, Xing Fu, Gary G. Meadows*. (2003) Specific Amino Acid Dependency Regulates Invasiveness and Viability of Androgen-Independent Prostate Cancer Cells. Nutrition and Cancer 45:1, 60-73
Online publication date: 1-Jan-2003.
Abstract | Printable PDF (919 KB) | PDF with links (230 KB)
W.K. Liu, S.C.W. Sze, J.C.K. Ho, B.P.L. Liu, M.C. Yu*. (2004) Wheat germ lectin induces G2/M arrest in mouse L929 fibroblasts. Journal of Cellular Biochemistry 91:6, 1159
CrossRef
Printable PDF (871 KB) PDF with links (117 KB)

07-15-2005, 07:07 PM	#14
al from canada Guest Posts: n/a	Here you go, Al Abstract Nutrition and Cancer 2000, Vol. 38, No. 1, Pages 123-130 (doi:10.1207/S15327914NC381_17) Molecular Mechanisms of Cell Cycle Block by Methionine Restriction in Human Prostate Cancer Cells Shan Lu, Daniel E. Epner* Previous studies have shown that dietary or pharmacological methionine restriction inhibits growth of human prostate cancer cells in vitro or as xenografts in mice. We undertook the present studies to clarify the molecular mechanisms by which methionine restriction inhibits prostate cancer cell growth. We found that PC-3 and DU 145 cells stopped proliferating within six days in growth medium containing homocysteine in place of methionine. In contrast, proliferation of LNCaP cells was only partially inhibited by the absence of methionine. Using flow cytometry, we found that methionine restriction caused PC-3 cells to arrest in all phases of the cell cycle, but predominantly in the G2/M phase, whereas LNCaP cells accumulated exclusively in the G1 phase. Methionine restriction led to accumulation of the cyclin-dependent kinase inhibitors p21 and p27, as determined by Western blot analysis, and inhibited the enzymatic activities of the cyclin-dependent kinases CDK2 and cdc2, as determined by an in vitro kinase assay. However, methionine restriction had little or no effect on CDK2 or cdc2 protein levels. Methionine restriction also induced PC-3 cells to undergo apoptosis, as indicated by the appearance of a typical nucleosomal ladder on gel electrophoresis of genomic DNA. We conclude that methionine restriction has potential as a novel treatment strategy for prostate cancer. Cited by Ya-Min Fu, Zu-Xi Yu, Yi-Qi Li, Xiaokang Ge, Phillip J. Sanchez, Xing Fu, Gary G. Meadows. (2003) Specific Amino Acid Dependency Regulates Invasiveness and Viability of Androgen-Independent Prostate Cancer Cells. Nutrition and Cancer 45:1, 60-73 Online publication date: 1-Jan-2003. Abstract \| Printable PDF (919 KB) \| PDF with links (230 KB) W.K. Liu, S.C.W. Sze, J.C.K. Ho, B.P.L. Liu, M.C. Yu. (2004) Wheat germ lectin induces G2/M arrest in mouse L929 fibroblasts. Journal of Cellular Biochemistry 91:6, 1159 CrossRef Printable PDF (871 KB) PDF with links (117 KB)