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Isoflavones may influence insulin action by means of their well-known receptor-mediated estrogenic activity. However, isoflavones also bind to PPAR's which are strongly associated with insulin action. Soy protein with its isoflavones has previously been shown to improve glycemic control in diabetic postmenopausal women and to improve insulin sensitivity in ovariectomized monkeys. The purpose of the current report was to extend our studies of dietary soy protein to male monkeys and determine effects of the soy isoflavones on insulin resistance. Two studies are reported here. Study one involved 91 male monkeys consuming three diets differing only by the source of protein (casein-lactalbumin, soy protein with a low isoflavone concentration or soy protein with a high isoflavone concentration). Intravenous glucose tolerance tests (IVGTTs) were done and plasma adiponectin and lipoprotein concentrations were determined after 25 months of study. Samples of visceral fat were obtained at 31 months for assessment adiponectin and PPARγ expression. The second study involved 8 monkeys in a Latin square design that compared the effects of diets with either casein/lactalbumin, soy protein with a high isoflavone concentration, or soy protein that was alcohol-washed to deplete the isoflavones. After eight weeks of treatment, insulin sensitivity and plasma lipoproteins were assessed. At ten weeks, skeletal muscle was biopsied for determination of insulin receptor, PPARα and PPARγ content. The major findings were that consumption of isoflavone-containing soy protein dose-dependently increased insulin responses to the glucose challenge and decreased plasma adiponectin while isoflavone-depleted soy protein decreased body weight and had no effect on plasma adiponectin concentrations. Muscle PPARα and γ expression was also increased with the isoflavone-depleted soy relative to either casein or soy protein containing the isoflavones. Further studies are needed to determine the mechanisms involved in these effects of a high soy isoflavone diet and to optimize dietary isoflavone content for maximal health benefits in males.

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Hodgkin's lymphoma (HL) is characterized by the presence of neoplastic Hodgkin and Reed-Sternberg cells (HRSC) in a background of inflammatory cells. Free radicals and oxidative stress generated in the inflammatory lesions could cause DNA damage, thus providing a basis for lymphomagenesis. Ataxia-telangiectasia mutated (ATM) and Rad3-related (ATR) genes are responsive genes for DNA damage, therefore the potential involvement of the ATR gene in HL pathogenesis was examined in 8 HL cell lines and 7 clinical cases. ATR alterations were detected in 6 out of 8 HL lines. Most aberrant transcripts observed were heterozygous deletions, which may have resulted from aberrant splicing. ATR aberrant transcripts were also detected in 3 out of 7 clinical cases. Three alterations, del exon 4, deletion exon 29-34 and insertion of 137 bp in exon 46/47 were commonly observed in both cell lines and clinical samples. HL cells with ATR alterations except del exon 4 showed a delay/abrogation in repair for DNA double-strand breaks (DSBs) and singlestrand break (SSB) as well as exhibiting a defect in p53 accumulation. These findings suggested the role of ATR gene alterations in HL lymphomagenesis.