Gender difference in the incidence of colorectal cancer is well known and has been supported by various epidemiologic studies. In Korea, women have lower incidence of colorectal cancer and adenoma, and the incidence in men has recently increased. Hormone replacement therapy in menopausal women is preventive of colorectal cancer but can cause cardiovascular diseases and breast cancer. Estrogen exerts diverse effects through estrogen receptors, ERalpha and ERbeta. ERbeta is associated with anti-proliferation and apoptosis. The ratio of ERalpha/ERbeta is important in the protection and tumorigenesis of colorectal cancer. Therefore ERbeta modulation has been investigated for preventing or treating colorectal cancer and avoiding adverse effects of estrogen at the same time. In addition, the gender-difference in the incidence of colorectal cancer should be taken into account when making guidelines on colorectal surveillance for Korean population.
Adenoma/diagnosis/epidemiology/mortality ; Colorectal Neoplasms/*diagnosis/epidemiology/mortality ; Estradiol Dehydrogenases/metabolism ; Estrogen Receptor alpha/metabolism ; Estrogen Receptor beta/metabolism ; Estrogens/*metabolism ; Humans ; Sex Factors

OBJECTIVETo investigate the expression of 17 beta-hydroxysteroid dehydrogenase type 1 (17β-HSD1) in the kidney of rats and explore the capacity of the kidney for synthesizing sex hormones.

METHODSThe expressions of 17-HSD1 and sex hormones were detected by Western blotting and radioimmunoassay in rat renal cells in primary cultured for 24 and 48 h in the presence or absence of follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

RESULTSAfter cell culture for 24 h, the primary rat renal cells expressed a low level of 17β-HSD1 (0.1843±0.076), which increased to 1.6651±0.044 (P<0.01) in response to co-stimulation by FSH and LH. Low levels of estradiol, progesterone and testosterone were also detected in rat renal cells (3.30±3.78, 62.60±12.33, and 22.12±3.36, respectively), and co-stimulation of FSH and LH significantly increased their levels to 8.50±2.64, 117.80±9.79, and 45.04±4.39, respectively (P<0.05). The levels of these hormones showed no significant differences between cells cultured for 24 h and 48 h (P>0.05).

CONCLUSIONThe rat renal cells express 17β-HSD1 and are capable of stably secreting sex hormones in response to co-stimulation with FSH and LH, suggesting the capacity of the rat kidneys for synthesizing sex hormones. These findings enrich the understanding of the endocrine function of the kidney.

17-Hydroxysteroid Dehydrogenases ; metabolism ; Animals ; Cells, Cultured ; Estradiol ; biosynthesis ; Follicle Stimulating Hormone ; pharmacology ; Kidney ; enzymology ; Luteinizing Hormone ; pharmacology ; Progesterone ; biosynthesis ; Rats ; Testosterone ; biosynthesis

OBJECTIVETo screen the proteins interacting with FXR1P for functional investigation of FXR1P.

METHODSThe yeast strain AH109 transformed with the recombinant expression vector pGBKT7/FXR1 was mated with the yeast strain Y187 pretransformed with human fetal brain cDNA library. The positive clones were screened and identified by sequence analysis.

RESULTSThe recombinant expression vector pGBKT7/FXR1 was constructed successfully. Five proteins binding to FXR1P were screened from human fetal brain cDNA library using the yeast two-hybrid system, including CMAS, FTH1, GOLGA4, HSD17B1 and CSH1.

CONCLUSIONSThese results provide new clues for investigating the biological functions of FXR1P and the pathogenesis of Fragile X syndrome.

Autoantigens ; genetics ; metabolism ; Estradiol Dehydrogenases ; genetics ; metabolism ; Ferritins ; genetics ; metabolism ; Gene Library ; Humans ; Membrane Proteins ; genetics ; metabolism ; Protein Binding ; Protein Interaction Domains and Motifs ; genetics ; RNA-Binding Proteins ; genetics ; metabolism ; Two-Hybrid System Techniques

OBJECTIVETo evaluate the inhibitory effect of genistin combined with anastrozole on the growth and apoptosis of breast tumor tissue, and to study their anti-cancer mechanism by using the model of 7,12-dimethylbenz [alpha] anthracene (DMBA)-induced mammary tumors following ovariectomy in Sprague-Dawley (SD) rats.

METHODSThe DMBA induced postmenopausal SD rats were randomly divided into the control group, the genistein group, the anastrozole group, and the genistein combined with anastrozole group. The growth of tumors was observed in each group. The proliferation index and apoptosis index of tumor cells were determined. Moreover, estradiol (E2) and 17beta-HSD1 mRNA levels were determined by ELISA and RT-PCR respectively.

RESULTSThe tumor growth was inhibited in the genistein group and the anastrozole group. The inhibitory ratio was significantly higher in the genistein combined with anastrozole group (P < 0.05). Compared with the control group, levels of E2 and 17beta-HSD1 mRNA decreased more significantly in the genistein combined with anastrozole group (P < 0.05).

CONCLUSIONSGenistein could suppress the growth of mammary tumors in postmenopausal rats. It showed synergistic effect when combined with anastrozole, which resulted in reduced levels of E2 and 17beta-HSD1 mRNA. It had inhibitory effect on the growth of breast tumors.

17-Hydroxysteroid Dehydrogenases ; metabolism ; Animals ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Estradiol ; metabolism ; Female ; Genistein ; administration & dosage ; pharmacology ; Mammary Neoplasms, Experimental ; chemically induced ; pathology ; Nitriles ; administration & dosage ; pharmacology ; Ovariectomy ; Postmenopause ; Rats ; Rats, Sprague-Dawley ; Triazoles ; administration & dosage ; pharmacology

OBJECTIVETo explore the mechanism of inhibitory effect of SLW on estrogen production by endometrial cells of endometriosis.

METHODAfter the model of eutopic primary cultured endometrial cells of endometiosis and hysteromyoma in vitro was successfully established, the changes of steroidgenic factor-1 (SF-1), chicken ovalbumin upstream-transcription factor (COUP-TF), 17-beta-hydroxysteroid dehydrogenase 1 (17-beta-HSD1) and 17-beta-hydroxysteroid dehydrogenase 2 (17-beta-HSD2) mRNA were detected by RT-PCR before and after treatment of medicated serum of SLW. The changes of SF-1 and COUP-TF protein were also observed by western blot synchronously according to the same treatment method mentioned-above. Meanwhile ,the data of hysteromyoma group was obtained from the above experiments.

RESULTThe expression of SF-1 mRNA and protein, 17-beta-HSD1 mRNA was weak, but COUP-TF mRNA and protein, 17-beta-HSD2 mRNA was remarkable in Hysteromyoma endometrium, as compared with those of endometiosis ,which was taken as control group (P<0.01). After the 48 hours' treatment of medicated serum of 5.0, 2.5 g kg(-1) d(-1) of SLW , the expression of COUP-TF mRNA and protein, 17beta-HSD2 mRNA was found significantly increased, but SF-1 mRNA and protein, 17-beta-HSD 1 mRNA was decreased in contrast to the control group (P <0.01 or P <0.05). Although the expresson of COUP-TF mRNA and protein was increased, SF-1 protein and 17-beta-HSD1 mRNA was decreased in 1.25 g kg(-1) d(-1) medicated serum group ,compared with those of the control group (P <0.01), the low dose group had no apparent inhibitory effect on the expression of SF-1, 17-beta-HSD2 mRNA.

CONCLUSIONThe medicated serum of SLW could inhibit the secretion of estradiol in eutopic endometrial cells of endometiosis, and its mechanism might be associated with combined action of inhibiting expression of SF-1, 17-beta-HSD1 and up-regulating expression of COUP-TF, 17-beta-HSD2.

17-Hydroxysteroid Dehydrogenases ; genetics ; Adult ; Animals ; COUP Transcription Factors ; genetics ; Drugs, Chinese Herbal ; pharmacology ; Endometriosis ; blood ; metabolism ; pathology ; Endometrium ; drug effects ; metabolism ; pathology ; Estradiol Dehydrogenases ; Estrogens ; biosynthesis ; Female ; Gene Expression Regulation ; drug effects ; Humans ; In Vitro Techniques ; Middle Aged ; RNA, Messenger ; genetics ; metabolism ; Rats ; Serum ; chemistry ; Steroidogenic Factor 1 ; genetics

OBJECTIVEThis study was designed to examine the in vitro effects of fenvalerate on steroid production and steroidogenic enzymes mRNA expression level in rat granulosa cells.

METHODSUsing primary cultured rat granulosa cells (rGCs) as model, fenvalerate of various concentrations (0, 1, 5, 25, 125, 625 micromol/L) was added to the medium for 24 h. In some cases, optimal concentrations of 22(R)-hydroxycholesterol (25 micromol/L), Follicle stimulating hormone (FSH, 2 mg/L), or 8-Bromo-cAMP (1 mmol/L) were provided. Concentrations of 17 beta-estradiol(E2) and progesterone (P4) in the medium from the same culture wells were measured by RIA and the steroidogenic enzyme mRNA level was quantified by semi-quantitative RT-PCR.

RESULTSFenvalerate decreased both P4 and E2 production in a dose-dependent manner while it could significantly stimulate rGCs proliferation. This inhibition was stronger in the presence of FSH. Furthermore, it could not be reversed by 22(R)-hydroxycholesterol or 8-Bromo-cAMP. RT-PCR revealed that fenvalerate had no significant effect on 3 beta-HSD, but could increase the P450scc mRNA level. In addition, 17 beta-HSD mRNA level was dramatically reduced with the increase of fenvalerate dose after 24 h treatment.

CONCLUSIONFenvalerate inhibits both P4 and E2 production in rGCs. These results support the view that fenvalerate is considered as a kind of endocrine-disrupting chemicals. The mechanism of its disruption may involve the effects on steroidogenesis signaling cascades and/or steroidogenic enzyme's activity.

3-Hydroxysteroid Dehydrogenases ; analysis ; metabolism ; 8-Bromo Cyclic Adenosine Monophosphate ; pharmacology ; Animals ; Base Sequence ; Cells, Cultured ; Dose-Response Relationship, Drug ; Estradiol ; analysis ; metabolism ; Female ; Follicle Stimulating Hormone ; pharmacology ; Granulosa Cells ; cytology ; drug effects ; metabolism ; Hydroxycholesterols ; pharmacology ; Nitriles ; pharmacology ; Progesterone ; analysis ; metabolism ; Pyrethrins ; pharmacology ; RNA, Messenger ; analysis ; metabolism ; Rats ; Steroids ; metabolism