An assessment is made of the anti-proliferative activity of cicada slough-derived materials against 10 human cancer cell lines, including PC-3 and DU145 prostate cancer cell lines, using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Results were compared with those of the commercially available anticancer agent with broad spectrum cisplatin. The ethanol extract of Cryptotympana spp. slough was proved to have anti-proliferative activity against A549 lung, AGS stomach, PC-3 and DU145 prostate, Hela cervix, HT-29 colon, MCF-7 breast, and SK-Hep-1 liver cancer cell lines except for Hep-2 larynx and SK-OV-3 ovary cancer cell lines. The biologically active constituent was characterized as the nonprotein α-amino acid theanine [2-amino-4-(ethylcarbamoyl)butyric acid] by spectroscopic analysis, including EI-MS and NMR. Theanine was isolated from the cicada slough as a new cytotoxic principle. Fifty percent inhibition concentration (IC50) values of the constituent against PC-3 was 6.52 μg/mL, respectively. The activity of theanine (IC50,6.52μg/mL) did not differ significantly from that of the anticancer agent cisplatin (IC50,7.39μg/mL) toward PC-3. In conclusion, further studies on the cicada slough-derived materials containing theanine as potential anticancer products or a lead molecule for the prevention or eradication from human prostate cancer.

Lung cancer caused by diverse changes in cells resulted by exposure to carcinogens found in tobacco smoke, the environment, or sequential accumulation of genetic changes to the normal epithelial cells of the lung. An assessment was made of the anti-proliferative activity of constituents from silkworm feces against 11 human cancer cell lines, including A549 and H727 lung cancer cell lines, using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The ethanol extract of silkworm feces was proved to have anti-proliferative activity against all 11 species of human cancer cell lines. The biologically active constituent was characterized as vomifoliol (blumenol A) (1) and stigmasterol (2) by spectroscopic analysis ,including MS and NMR. In conclusion, global efforts to reduce the level of antitcancer agents justify further studies on the silkworm feces-derived materials containing vomifoliol and stigmasterol as potential anticancer products or lead compounds for the prevention or eradication from human lung cancer.

The Egr family of zinc finger transcription factors is rapidly induced by various mitogens and regulates cell growth, differentiation, and apoptosis. While it is clear that loss of Egr1 leads to anovulatory infertility due to LHβ deficiency in female mice, molecular function of Egr1 in male reproduction has not been clearly investigated. Here, we demonstrate that Egr1 acts as an intrinsic transcription factor in Leydig cells to regulate their proliferation and steroidogenesis in the testis as well as an extrinsic factor for male reproduction via LHβ transcription in the pituitary. Egr1 is predominantly expressed in spermatogonia and Leydig cells in immature testes and later detected in some of these cell types in mature testes. The fertility potential of Egr1(-/-) male mice is relatively deteriorated even at 2 month-old age and aggravated with aging. The incidence of abnormalities of seminiferous tubules such as Sertoli cell only was dramatically increased with aging. The number and mean size of Leydig cells were significantly reduced in Egr1(-/-) testes. The impairment of Leydig cells is consistent with significant reduction in levels of testosterone and expression of factors critical for steroidogenesis such as StAR in Egr1(-/-) testes. Exogenous administration of hCG rapidly and transiently induced Egr1 expression in Leydig cells culture in vitro. hCG could reinstate reduced mean size of Leydig cells but not reduced number of Leydig cells and aberrantly low StAR expression, suggesting that Egr1 has critical functions for Leydig cell proliferation and their steroidgenesis. In addition, daily sperm production and in vitro fertilization (IVF) competence were significantly reduced, and apoptosis was facilitated in these mice. Furthermore, hCG administration to compensate for relatively low LH levels in Egr1(-/-) males could not restore the compromised reproductive phenotypes such as IVF competence and apoptosis in these mice. Interestingly, expression of Egr2, a member of Egr family, is significantly elevated in Egr1(-/-) Leydig cells suggesting that genetic compensation of Egr2 may alleviate phenotypic aberration of Egr1(-/-) male testes. Collectively, these results suggest that Egr1 act as an intrinsic transcription factor required for proliferation and steroidogenesis of Leydig cells to govern spermatogenesis in the testis.