Biotin attenuates heat shock factor 4b transcriptional activity by lysine 444 biotinylation.

Genetic mutations in HSF4 cause congenital cataracts. HSF4 exhibits both positive and negative regulation on the transcription of heat shock and non-heat shock proteins during lens development, and its activity is regulated by posttranslational modifications. Biotin is an essential vitamin that regulates gene expression through protein biotinylation. In this paper, we report that HSF4b is negatively regulated by biotinylation. Administration of biotin or ectopic bacterial biotin ligase BirA increases HSF4b biotinylation at its C-terminal amino acids from 196 to 493. This attenuates the HSF4b-controlled expression of αB-crystallin in both lens epithelial cells and tested HEK293T cells. HSF4b interacts with holocarboxylase synthetase (HCS), a ubiquitous enzyme for catalyzing protein biotinylation in mammal. Ectopic HA-HCS expression downregulates HSF4b-controlled αB-crystallin expression. Lysine-mutation analyses indicate that HSF4b/K444 is a potential biotinylation site. Mutation K444R reduces the co-precipitation of HSF4b by streptavidin beads and biotin-induced reduction of αB-crystallin expression. Mutations of other lysine residues such as K207R/K209R, K225R, K288R, K294R and K355R in HSF4's C-terminal region do not affect HSF4's expression level and the interaction with streptavidin, but they exhibit distinct regulation on αB-crystallin expression through different mechanisms. HSF4/K294R leads to upregulation of αB-crystallin expression, while mutations K207R/K209R, K225R, K288R, K255R and K435R attenuate HSF4's regulation on αB-crystallin expression. K207R/K209R blocks HSF4 nuclear translocation, and K345R causes HSF4 destabilization. Taken together, the data reveal that biotin maybe a novel factor in modulating HSF4 activity through biotinylation.

The Therapeutic Roles of Recombinant Hsp90α on Cornea Epithelial Injury.

Purpose: The purpose of this study was to explore the therapeutic role of heat shock protein 90 (Hsp90) in wound healing of injury cornea epithelium. Methods: The right eye of C57BL/6N male mice were performed the debridement wounds in the center of the cornea using an algerbrush II blade. The injured area was determined by staining the cornea with fluorescein sodium and measured with image-J. Immunoblotting, ELISA and immunochemistry were used for determining protein expression. The quantitation PCR was performed to measure mRNA expression. Results: Hsp90α is upregulated at both the mRNA and protein levels, and is secreted extracellularly into the corneal stroma and tear film during the healing process after corneal injury in mice. This upregulation is associated with activation of HSF1. Administration of recombinant exogenous Hsp90α (eHsp90α) speeds up wound healing of injured corneal epithelium. The eHsp90α binds to low-density lipoprotein (LDL)-related protein-1 (LRP-1) on the corneal epithelial cells and increases phosphorylation of AKT at S473, which is associated with proliferation and migration corneal epithelial cells in vitro or vivo. Inhibition of AKT by its inhibitor LY294002 abolishes eHsp90α-induced migration and proliferation of corneal epithelial cells. Conclusion: Hsp90α is upregulated and secreted after corneal injury and acts to promote the healing process. Recombinant Hsp90α may be a promising therapeutic drug candidate for corneal injury.

FcRn is not the receptor mediating the transfer of serum IgG to colostrum in pigs.

In contrast to humans or rabbits, in which maternal IgG is transmitted to offspring prenatally via the placenta or the yolk sac, large domestic animals such as pigs, cows and sheep transmit IgG exclusively through colostrum feeding after delivery. The extremely high IgG content in colostrum is absorbed by newborns via the small intestine. Although it is widely accepted that the neonatal Fc receptor, FcRn, is the receptor mediating IgG transfer across both the placenta and small intestine, it remains unclear whether FcRn also mediates serum IgG transfer across the mammary barrier to colostrum/milk, especially in large domestic animals. In this study, using a FcRn knockout pig model generated with a CRISPR-Cas9-based approach, we clearly demonstrate that FcRn is not responsible for the IgG transfer from serum to colostrum in pigs, although like in other mammals, it is involved in IgG homeostasis and mediates IgG absorption in the small intestine of newborns.

Monoclonal antibody AC10364 inhibits cell proliferation in 5-fluorouracil resistant hepatocellular carcinoma via apoptotic pathways.

BACKGROUND: This study was designed to investigate the antitumor activity of the mAb (AC10364) in vitro and elucidate the related mechanisms of inhibition to cell growth using bel/fu cells treated with AC10364. METHODS: The inhibitory effects of AC10364 on the proliferation of Bel/fu cells were examined using a cytotoxicity assay. Apoptosis of Bel/fu cells was detected using FITC annexin V and PI staining following treatment with AC10364 for 24 h. The factors regulating apoptosis were identified by Western blot using lysates of Bel/fu cells treated with AC10364 for 0, 12, 24, or 36 h. Genes associated with tumorigenesis or growth were analyzed by reverse transcription-quantitative polymerase chain reaction using Bel/fu cells treated for 12, 24, or 36 h with AC10364. RESULTS: The early apoptotic ratios of Bel/fu cells treated with AC10364 increased in a dose-dependent manner. The levels of caspases, including cleaved caspase-3, caspase-3 and caspase-9, were significantly high in Bel/fu cells treated with AC10364 (P<0.001). Compared with untreated cells, those exposed to AC10364 had showed significant downregulation of the expression of binding protein gene (G protein subunit α 15, GNA15) and other protein-coding genes, including fms-related tyrosine kinase 1(FLT1), nicotinamide phosphoribosyltransferase (NAMPT), netrin 4 (NTN4), platelet-derived growth factor subunit A (PDGFA), S100 calcium binding protein A11 (S100A11), tubulin ß 3 class III (TUBB3), aldo-keto reductase family 1 member C3 (AKR1C3), endothelial PAS domain protein 1 (EPAS1), and interferon α-inducible protein 27 (IFI27) (P<0.001). Two other genes, AXL receptor tyrosine kinase (AXL) and carboxypeptidase A4 (CPA4), were significantly upregulated (P<0.001). CONCLUSION: AC10364 inhibited cell viability and proliferation through aberrant expression of multiple genes associated with tumorigenesis or growth, which suggests that these genes may be promising therapeutic candidates for cancer therapy.

SNAP23 suppresses cervical cancer progression via modulating the cell cycle.

OBJECTIVE: Cervical cancer (CC) is one of the most common gynecologic tumors in women worldwide, with poor prognosis and low survival rate. In this study, we identified SNAP23 as a potential tumor suppressor gene in CC. METHODS: The expression of SNAP23 in tissues and cell lines were measured by qRT-PCR, western blot and IHC. Knockdown of SNAP23 by siRNA and ectopic expression of SNAP23 by overexpression plasmid were performed to observe the biological function of SNAP23 in CC. Xenograft nude mice models were established to measure its function in vivo. RESULTS: SNAP23 was downregulated in CC tissues and had a negative correlation with advanced clinical characteristics. Ectopic expression of SNAP23 suppressed malignant phonotype of CC while knockdown of SNAP23 promoted the progression of CC in vitro. The flow cytometry analysis revealed that SNAP23 exerted its tumor suppressor activity via inducing G2/M cell cycle arrest. Moreover, xenograft tumor models showed that SNAP23 suppresses tumor growth in vivo. CONCLUSIONS: Our results revealed that SNAP23 suppressed progression of CC and induced cell cycle G2/M arrest via upregulating p21cip1 and downregulating CyclinB1.

Selective suppression of the JNK-MMP2/9 signal pathway by tetramethylpyrazine attenuates neuropathic pain in rats.

BACKGROUND: Activated astrocytes release matrix metalloproteinase-2/9 (MMP-2/9) to induce central sensitization and maintain neuropathic pain. However, the mechanisms involved in the activation of MMP-2/9 on astrocytes during pain remain poorly understood. Meanwhile, there is a lack of effective treatment to inhibit the activation of MMP-2/9 on astrocytes. In this study, we aim to investigate the effect of tetramethylpyrazine (TMP), a natural compound with analgesic effects but unknown mechanisms, on MMP-2/9 in neuropathic pain. METHODS: The nociception was assessed by measuring the incidence of foot withdrawal in response to mechanical indentation in rats (n = 6). Cell signaling was assayed using western blotting (n = 6) and immunohistochemistry (n = 5). The astrocyte cell line C8-D1A was cultured to investigate the in vitro effects. RESULTS: TMP significantly attenuated the maintenance of chronic constrictive injury (CCI)-induced neuropathic pain, inhibited the activation of astrocytes, and decreased the expression of MMP-2/9. Furthermore, our results indicated that TMP could selectively suppress JNK activity but had no notable effects on ERK and p38. Our study also revealed that the effect of TMP may be dependent on the inhibition of TAK1. CONCLUSIONS: Inhibition of astrocyte activation in the spinal cord by tetramethylpyrazine may have utility in the treatment of CCI-induced neuroinflammation, and our results further implicate JNK-MMP-2/9 as a novel target for the attenuation of neuropathic pain.

SNAP23 promotes the malignant process of ovarian cancer.

BACKGROUND: Ovarian cancer (OC) was the primary malignant gynecological cancer and SNARE protein is closely related with tumor progression. Here, we identified SNAP23, a member of SNARE complex, as a potential oncogene in OC. METHODS: We determined the expression of SNAP23 in OC tissues and explored the clinical significance through bioinformatics analysis. The effects of SNAP23 on OC cell proliferation, migration, invasion, cell cycle and apoptosis were then evaluated in vitro. RESULTS: SNAP23 is hyper-expressed in OC tumor tissues compared to normal tissues, and increased expression of SNAP23 is associated with a poor progression free survival (HR = 1.24, 95% CI = 1.07-1.44, p = 0.0042). SNAP23 knock down increases cell apoptosis and inhibits cell proliferation, migration and invasion of OC cells. GO analysis reveals that most genes correlated highly with SNAP23 were enriched in metabolic process. CONCLUSIONS: Our data suggest that SNAP23 may serve as an oncogene promoting tumorigenicity of OC cells by decreasing apoptotic process.

Video Endoscopic Inguinal Lymphadenectomy via 3-Incision Lateral Approach for Vulvar Cancers: Our Preliminary Outcome of 37 Cases.

OBJECTIVE: The purpose of this study was to build a video endoscopic inguinal lymphadenectomy (VEIL) via the 3-incision superolateral inguinal approach and explore the feasibility and significance of this method for vulvar cancer. METHODS: Thirty-seven patients with vulvar cancer who underwent VEIL via the 3-incision superolateral inguinal approach were enrolled and followed up. The number of excised lymph nodes, intraoperative complications, inguinal wound healing, and the prognosis were retrospectively analyzed. RESULTS: The average number of excised lymph nodes per side is 8.8 ± 3.7 (4-18) among the 37 patients and after the new method was more mature, is 9.6 ± 3.6 among the 34 patients treated. Primary healing was found in 36 cases, whereas delayed healing occurred in 1 case complicated with diabetes. The lymph node-positive patients (6 cases) were supplemented with postoperative radiochemotherapy (RCT). All patients survived during the follow-up. Of the 2 recurrent patients, one patient who received surgery again and RCT survived without tumor. The other patient undergoing RCT survived with tumor. CONCLUSIONS: Compared with open lymphadenectomy, VEIL via the 3-incision lateral approach provides a feasible, but more cosmetic, and promising minimally invasive modality in clinic for treating patients with vulvar cancer.

The Higher Response of Vascular Endothelial Growth Factor and Angiotensin-II to Human Chorionic Gonadotropin in Women with Polycystic Ovary Syndrome.

BACKGROUND: This research investigated the response of vascular active factors, vascular endothelial growth factor (VEGF) and angiotensin-II (AT-II) to ovarian stimulation during 24 hours in patients with polycystic ovary syndrome (PCOS). MATERIALS AND METHODS: In this clinical trial study, 52 patients with PCOS and 8 control cases were stimulated with human chorionic gonadotropin (HCG) on the 4(th) to 7(th) day of the patients' natural or induced menstrual cycles. We measured VEGF and AT-II by radioimmunoassay before the injection (0 hour) and 3, 8, 12, 18 and 24 hours after the stimulation. RESULTS: After ovarian stimulation, there was substantially higher level of VEGF in typical PCOS patients than the other three groups at the 3 hour time point (p<0.05), while there were no significant differences in VEGF at all the other time points among the four groups. As for AT-II, before and at all time points after the ovarian stimulation, it seemed that the AT-II levels in patients' sera with different phenotypes of PCOS by the Rotterdam criteria were all higher than in the control group although the differences were not statistically significant. The level of AT-II in typical PCOS patients was also significantly higher than the other three groups at the 3 hour time point (p<0.05), while no significant differences at all the other time points among the four groups were observed. CONCLUSION: The response to the stimulation varied among patients with different phenotypes of PCOS according to the Rotterdam criteria. Serum VEGF and AT-II were possible contributors to an increased risk of developing ovarian hyperstimulation syndrome (OHSS) in patients with typical PCOS during the early follicular phase (3 hours) after ovarian stimulation ( REGISTRATION NUMBER: NCT02265861).

Genetic variants at 6p21.1 and 7p15.3 Identified by GWASs of multiple cancers and ovarian cancer risk: a case-control study in Han Chinese women.

A recent study summarized several published genome-wide association studies (GWASs) of cancer and reported two pleiotropic loci at 6p21.1 and 7p15.3 contributing to multiple cancers including lung cancer, noncardia gastric cancer (NCGC), and esophageal squamous-cell carcinoma (ESCC) in Han Chinese. However, it is not known whether such genetic variants have similar effects on the risk of gynecologic cancers, such as ovarian cancer. Hence, we explored associations between genetic variants in 6p21.1 and 7p15.3 and ovarian cancer risk in Han Chinese women. We performed an independent case-control study by genotyping the two loci (rs2494938 A > G at 6p21.1 and rs2285947 A > G at 7p15.3) in a total of 377 ovarian cancer cases and 1,034 cancer-free controls using TaqMan allelic discrimination assay. We found that rs2285947 at 7p15.3 was significantly associated with risk of ovarian cancer with per allele odds ratio (OR) of 1.33 [95% confidence interval (CI): 1.08-1.64, P=0.008]. However, no significant association was observed between rs2494938 and ovarian cancer risk. Our results showed that rs2285947 at 7p15.3 may also contribute to the development of ovarian cancer in Han Chinese women, further suggesting pleiotropy of 7p15.3 in multiple cancers.

Mechanistic analysis of taxol-induced multidrug resistance in an ovarian cancer cell line.

OBJECTIVES: To establish a taxol-resistant cell line of human ovarian carcinoma (A2780/Taxol) and investigate its biological features. METHODS: The drug-resistant cell line (A2780/Taxol) was established by continuous stepwise selection with increasing concentrations of Taxol. Cell morphology was assessed by microscopy and growth curves were generated with in vitro and in vivo tumor xenograft models. With rhodamine123 (Rh123) assays, cell cycle distribution and the apoptotic rate were analyzed by flow cytometry (FCM). Drug resistance-related and signal associated proteins, including P-gp, MRPs, caveolin-1, PKC-α, Akt, ERK1/2, were detected by Western blotting. RESULTS: A2780/Taxol cells were established with stable resistance to taxol. The drug resistance index (RI) was 430.7. Cross-resistance to other drugs was also shown, but there was no significant change to radioresistance. Compared with parental cells, A2780/Taxol cells were significantly heteromorphous, with a significant delay in population doubling time and reduced uptake of Rh123 (p < 0.01). In vivo, tumor take by A2780 cells was 80%, and tumor volume increased gradually. In contrast, with A2780/Taxol cells in xenograft models there was no tumor development. FCM analysis revealed that A2780/Taxol cells had a higher percentage of G0/G1 and lower S phase, but no changes of G2 phase and the apoptosis rate. Expression of P-gp, MRP1, MRP2, BCRP, LRP, caveolin-1, PKC-α, Phospho-ERK1/2 and Phospho-JNK protein was significantly up-regulated, while Akt and p38 MARK protein expression was not changed in A2780/Taxol cells. CONCLUSION: The A2780/Taxol cell line is an ideal model to investigate the mechanism of muti-drug resistance related to overexpression of drug-resistance associated proteins and activation of the PKC-α/ERK (JNK) signaling pathway.

Secondary cytoreduction surgery improves prognosis in platinum-sensitive recurrent ovarian cancer.

BACKGROUND: There is no consensus regarding the secondary cytoreduction surgery (CRS) in recurrent ovarian cancer patients. The present study aims to determine the value of secondary CRS and the eligible subgroup for this procedure. METHODS: 96 platinum-sensitive recurrent ovarian cancer patients were recruited from Jiangsu Institute of Cancer Research between 1992 and 2011. Follow-up was conducted based on the surveillance protocol of MD Anderson Cancer Center. Cox proportional hazards model and log-rank test were used to assess the associations between the survival durations and covariates. Logistic regression analysis was used to explore optimal secondary CRS related factors. RESULTS: Optimal secondary CRS was associated with time to progression (TTP) and overall survival (OS) in patients (p < 0.01 both). Optimal secondary CRS and asymptomatic recurrent were similarly associated with longer OS (median: 79.2 vs. 53.9 and 76.1 vs. 56.0 months with p = 0.02 and p = 0.04, respectively) and TTP (median: 13.9 vs. 10.5 and 19.3 vs. 9.0 months with p = 0.02 and p = 0.03, respectively) than counterparts. Optimal initial CRS (p = 0.01), asymptomatic recurrent (p = 0.02) and longer progression-free survival duration (p = 0.02) were the independent indicators of optimal secondary CRS. CONCLUSIONS: Optimal secondary CRS had survival benefit for platinum-sensitive epithelial ovarian cancer. Asymptomatic recurrent was one of the recruited factors for this procedure.

Nadir CA-125 level as prognosis indicator of high-grade serous ovarian cancer.

PURPOSE: The capacity of nadir CA-125 levels to predict the prognosis of epithelial ovarian cancer remains controversial. This study aimed to explore whether the nadir CA-125 serum levels could predict the durations of overall survival (OS) and progression free survival (PFS) in patients with high-grade serous ovarian cancer (HG-SOC) from the USA and PRC. MATERIALS AND METHODS: A total of 616 HG-SOC patients from the MD Anderson Cancer Center (MDACC, USA) between 1990 and 2011 were retrospectively analyzed. The results of 262 cases from the Jiangsu Institute of Cancer Research (JICR, PRC) between 1992 and 2011 were used to validate the MDACC data. The CA-125 immunohistochemistry assay was performed on 280 tissue specimens. The Cox proportional hazards model and the log-rank test were used to assess the associations between the clinicopathological characteristics and duration of survival. RESULTS: The nadir CA-125 level was an independent predictor of OS and PFS (p < 0.01 for both) in the MDACC patients. Lower nadir CA-125 levels (≤10 U/mL) were associated with longer OS and PFS (median: 61.2 and 16.8 months with 95% CI: 52.0-72.4 and 14.0-19.6 months, respectively) than their counterparts with shorter OS and PFS (median: 49.2 and 10.5 months with 95% CI: 41.7-56.7 and 6.9-14.1 months, respectively). The nadir CA-125 levels in JICR patients were similarly independent when predicting the OS and PFS (p < 0.01 for both). Nadir CA-125 levels less than or equal to 10 U/mL were associated with longer OS and PFS (median: 59.9 and 15.5 months with 95% CI: 49.7-70.1 and 10.6-20.4 months, respectively), as compared with those more than 10 U/mL (median: 42.0 and 9.0 months with 95% CI: 34.4-49.7 and 6.6-11.2 months, respectively). Baseline serum CA-125 levels, but not the CA-125 expression in tissues, were associated with the OS and PFS of HG-SOC patients in the MDACC and JICR groups. However, these values were not independent. Nadir CA-125 levels were not associated with the tumor burden based on second-look surgery (p = 0.09). Patients who achieved a pathologic complete response had longer OS and PFS (median: 73.7 and 20.7 months with 95% CI: 63.7-83.7 and 9.5-31.9 months, respectively) than those with residual tumors (median: 34.6 and 10.6 months with 95% CI: 6.9-62.3 and 4.9-16.3 months, respectively). CONCLUSIONS: The nadir CA-125 level was an independent predictor of OS and PFS in HG-SOC patients. Further prospective studies are required to clinically optimize the chances for a complete clinical response of HG-SOC cases with higher CA-125 levels (>10 U/mL) at the end of primary treatment.

Clinical application of endoscopic inguinal lymph node resection after lipolysis and liposuction for vulvar cancer.

AIM: To examine lymph nodes obtained after lipolysis and liposuction of subcutaneous fat of the inguinal region of female vulvar cancer patients to explore the feasibility of clinical application. METHODS: The field of operation was on the basis of the range of the conventional resection of inguinal lymph nodes. We injected lipolysis liquid fanwise, started liposuction after 15-20 minutes; then the subcutaneous fatty tissue was sucked out clearly by suction tube. We selected the first puncture holes located on 2-3 cm part below anterior superior spine, the others respectively being located 3cm and 6cm below the first for puncturing into the skin, imbedding a trocar to intorduce CO2 gas and the specular body, and excise the lymph nodes by ultrasonic scalpel. The surgical field chamber was set with negative pressure drainage and was pressured with a soft saline bag after surgery. RESULTS: A lacuna emerged from subcutaneous of the inguinal region after lipolysis and liposuction, with a wide fascia easily exposed at the bottom where lymph nodes could be readily excised. The number of lymph nodes of ten patients excised within the inguinal region on each side was 4-18. The excised average number of lymph nodes was 11 when we had mature technology. CONCLUSION: Most of adipose tissue was removed after lipolysis and liposuction of subcutaneous tissue of inguinal region, so that the included lymph nodes were exposed and easy to excise by endoscope. This surgery avoided the large incision of regular surgery of inguinal region, the results indicating that this approach is feasible and safe for used as an alternative technology.

Modulation of drug resistance in ovarian cancer cells by inhibition of protein kinase C-alpha (PKC-α) with small interference RNA (siRNA) agents.

OBJECTIVE: To determine whether silence of PKC-α expression by small interference RNA (siRNA) might regulate MDR1 expression and reverse chemoresistance of ovarian cancer. METHODS: We measured gene and protein expression of MDR1 and PKC-α in ovarian cancer cells and assessed their correlation with cell drug resistance. We also examined whether blocking PKC-α by RNA interference (RNAi) affected MDR1 expression and reversed drug resistance in drug sensitivity tests. RESULTS: The drug resistance cell lines, OV1228/DDP and OV1228/Taxol, had higher gene and protein expression of MDR1 and PKC-α than their counterpart sensitive cell line, OV1228. SiRNA depressed PKC-α gene protein expression, as well as MDR1 and protein expression and improved the drug sensitivity in OV1228/DDP and OV1228/Taxol cells. CONCLUSION: These results indicated that decreasing PKC-α expression with siRNA might be an effective method to improve drug sensitivity in drug resistant cells with elevated levels of PKC-α and MDR1. A new siRNA-based therapeutic strategy targeting PKC-α gene could be designed to overcome the chemoresistance of ovarian cancer.

The impairment of reproduction in db/db mice is not mediated by intraovarian defective leptin signaling.

OBJECTIVE: To demonstrate whether leptin modulates reproduction by a direct effect within the ovary. DESIGN: Animal model. SETTING: National Key Laboratory of Infertility. ANIMAL(S): Adult female db/db mice. INTERVENTION(S): Adult littermate wild-type (WT) and diabetic (db) leptin receptor (LR) mutant female mice were matched for the allograft of the ovary to construct new genotypic models, respectively. WT mouse received only one ovary from a WT or a db/db mouse (WT Ov-WT, WT Ov-db), and db/db mouse received one ovary from a WT or a db/db mouse (db Ov-WT, db Ov-db). WT and db/db mice received one ovary from a WT mouse and another ovary from a db/db mouse (WT Ov-WT/db, db Ov-WT/db) or received two ovaries all from a WT mouse (db Ov-WT/WT). MAIN OUTCOME MEASURE(S): Hormones, lipids, and reverse transcription polymerase chain reaction. RESULT(S): Both WT Ov-WT and WT Ov-db mice presented normal cycles, comparable serum E(2) and FSH levels, and ovarian expressions of the Star, Cyp17, and Cyp19 mRNA, even with different ovary genotypes. In WT Ov-WT/db with hMG stimulation, db ovaries with LR mutation expressed higher Star, Cyp17, Cyp19, Jak2, Stat3, and Pias3 mRNA than in the basal state, whereas WT ovaries with intact LR expressed higher Star, Cyp17, and Cyp19 but divergently lower Jak2, Stat3, and Pias3 levels. CONCLUSION(S): We confirmed that impairment of reproduction in intact db/db mice is not mediated by intraovary intact/defective leptin signaling even in face of a divergent modulation by gonadotropins.

Different phenotypes of polycystic ovary syndrome by Rotterdam criteria are differently steroidogenic but similarly insulin resistant.

In traditional Chinese medicine, polycystic ovary syndrome (PCOS) is considered an anovulation disorder related to ovarian insulin resistance. The three phenotypes of PCOS, according to the Rotterdam criteria, are differently steroidogenic but similarly insulin resistant, suggesting a similar involvement of insulin resistance/hyperinsulinemia in different compartments of the PCOS ovary, namely, overactive theca and/or granulosa cells.

Response of IGF and IL-6 to ovarian stimulation in PCOS and normal women.

The objective of the present study was to investigate the response patterns of insulin-like growth factors (IGFs) and interleukin-6 (IL-6) to ovarian stimulation within 24 h in patients with polycystic ovary syndrome (PCOS) in comparison with normally ovulating women. This controlled prospective clinical study involved 60 women who attended an infertility clinic. For the induction of the ovarian stimulation, fifty-two patients with PCOS and eight control cases were injected with human menopause gonadotropin (hMG) and human chorionic gonadotropin (hCG) during the early follicular phase of the natural or induced menstrual cycle. The blood was sampled before (0h) and 6, 12, 18, and 24 h after the stimulation. Serum levels of estradiol (E2), IGF-I, IGF-II and IL-6 were measured by radioimmunoassay. A significant decrease in serum IGF-II at 12 h was observed after a mixture of hMG and hCG was administered in patients with polycystic ovaries (PCO) including the typical PCOS group and the PCO + OA group (accumulated p < 0.05), while normal women presented a slight decrease (accumulated p < 0.1) 18h after the stimulation. Moreover, all the groups had similar serum levels of IL-6 and IGF-I at all time points. An increase in serum E2 occurred coincident with a decrease in IGF-II in all the groups except the ovarian hyperandrogenism patients (HA + OA group). Serum IGF-II levels, which appeared to be negatively correlated with elevated E2, statistically decreased in PCO patients early after hMG and hCG administration when monitored for 24 h, while no such changes were observed in IGF-I and IL-6.

Insulin resistance directly contributes to androgenic potential within ovarian theca cells.

OBJECTIVE: To investigate whether insulin resistance (IR) within theca cells may directly contribute to their hyperandrogenism, a heritable trait of polycystic ovary syndrome (PCOS). DESIGN: In vitro cell model. SETTING: University-affiliated laboratory. ANIMAL(S): Porcine ovaries. INTERVENTION(S): Ovarian theca cells from porcine follicles were isolated and cultured. Insulin resistance was induced in theca cells without (Con) or with dexamethasone (Dex); cells were further treated by troglitazone (Tro) and metformin (Met) in IR cells or by vehicle only in IR and Con cells. MAIN OUTCOME MEASURE(S): Medium glucose and T levels; reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot for insulin signal molecules and androgenic enzyme. RESULT(S): As compared with Con cells, Dex-treated cells had significantly lower [(3)H]-glucose uptake (565 +/- 58 cpm/10(6) vs. 1077 +/- 78 cpm/10(6)) but higher medium glucose levels (16.31 +/- 0.39 nmol/L vs. 10.62 +/- 1.02 nmol/L) and had approximately twofold T levels (0.82 +/- 0.20 microg/L vs. 0.38+/-0.08 microg/L). Troglitazone and Met significantly reduced the medium glucose and testosterone concentrations to levels comparable to those in Con cells. The RT-PCR and Western blot showed that the two sensitizers in different ways reversed the altered messenger RNA and protein expression of insulin receptor substrate-1, glucose transporter-4, peroxisome proliferator-activated receptor-gamma, and 17 alpha-hydroxylase in Dex-induced IR cells. CONCLUSION(S): Insulin resistance induced by Dex could directly exaggerate androgenic potential within theca cells, suggesting the possible involvement of this ovarian metabolic phenotype in PCOS hyperandrogenism.

[Microsatellite polymorphism of (tttta) n in the promoter of CYP11a gene in Chinese women with polycystic ovary syndrome].

OBJECTIVE: To investigate the distribution of (tttta) n microsatellite polymorphism in the promoter of CYP11a gene in Chinese women with polycystic ovary syndrome (PCOS) and the relationship between such polymorphism and PCOS. METHODS: Peripheral blood samples were obtained from 201 women with PCOS, aged 26 +/- 4, and 147 women without PCOS, aged 29 +/- 5. Radioimmunoassay was used to examine the levels of testosterone, follicle-stimulating hormone, luteinizing hormone, progesterone, estradiol, and prolactin. Locus-specific prime PCR was used to detect the frequencies of the CYP11a alleles. Body mass index (BMI) was calculated. RESULTS: The average BMI of the women with PCOS was 22 kg/m(2) +/- 4 kg/m(2), and that of the non-PCOS women was 22 kg/m(2) +/- 6 kg/m(2). The six-repeat allele variant genotypic distribution of CYP11a was statistically different between the women with PCOS and those without PCOS [Fisher's exact test (2-tail), P = 0.031]. The frequency of 6//6 genotype in the PCOS patients was 57.7% (116/201), significantly higher than that of the non-PCOS women [44.9% (66/147), chi(2) = 5.588, P = 0.018]. The BMI of the PCOS patients with 4//4 genotype was 19.4 kg/m(2) +/- 1.7 kg/m(2), statistically lower than those of the PCOS patients with 4//6, 6//6, and 6//8 genotypes (23.6 kg/m(2) +/- 3.3 kg/m(2), 22.5 kg/m(2) +/- 3.8 kg/m(2), 22.2 kg/m(2) +/- 4.2 kg/m(2) respectively, P = 0.0037, 0.0027, and 0.059 respectively). The PCOS patients with the allele (tttta) 6 had markedly higher BMI (22.7 kg/m(2) +/- 3.7 kg/m(2)) than those without the allele (tttta) 6 (19.4 kg/m(2) +/- 1.7 kg/m(2), P = 0.0075). No differences were observed in the serum levels of reproductive hormones among the individuals with different genotypic features in the PCOS patients. CONCLUSION: The six-repeat allele is the most common fragment of (tttta) n microsatellite polymorphism in Chinese Han woman. The 6//6 genotype is significantly more frequent and is associated with greater BMI in the women with PCOS. The six-repeat allele variant may play a certain role in the pathogenesis of PCOS.