Guidelines for office gynecology in Japan: Japan Society of Obstetrics and Gynecology (JSOG) and Japan Association of Obstetricians and Gynecologists (JAOG) 2017 edition.

Six years after the first edition of The Guideline for Gynecological Practice, which was jointly edited by The Japan Society of Obstetrics and Gynecology and The Japan Association of Obstetricians and Gynecologists, the third revised edition was published in 2017. The 2017 Guidelines includes 10 additional clinical questions (CQ), which brings the total to 95 CQ (12 on infectious disease, 28 on oncology and benign tumors, 27 on endocrinology and infertility and 28 on healthcare for women). Currently a consensus has been reached on the Guidelines and therefore the objective of this report is to present the general policies regarding diagnostic and treatment methods used in standard gynecological outpatient care that are considered appropriate. At the end of each answer, the corresponding recommendation level (A, B, C) is indicated.

High Expression of Ubiquitin C-terminal Hydrolase L1 Is Associated With Poor Prognosis in Endometrial Cancer Patients.

OBJECTIVE: The ubiquitin C-terminal hydrolase L1 (UCHL1) plays a key role in tumor invasion and metastasis. Ubiquitin C-terminal hydrolase L1 is overexpressed in various cancers and reported to be correlated with a poor prognosis. The objective of this study was to determine the prognostic significance of UCHL1 in endometrial cancer. METHODS: The expression of UCHL1 in endometrial cancer was assessed using quantitative reverse transcription polymerase chain reaction and immunohistochemistry in 56 and 215 resected tumor specimens, respectively. RESULTS: The 4-year survival rates of the high UCHL1 messenger RNA expression group and high UCHL1 protein expression group were 78% and 71%, respectively, compared with 96% and 95% for the low UCHL1 messenger RNA expression group and low UCHL1 protein expression group, respectively. Kaplan-Meier and log-rank tests indicated a significant correlation between expression of UCHL1 and disease-free survival and overall survival. Moreover, multivariate stepwise Cox proportional hazard regression model analysis showed that UCHL1 was a significant independent marker for predicting a poor disease-free survival and overall survival. In 43 patients with metastatic lesions, immunohistochemical analysis of metastatic lesions revealed that the recurrence rate and mortality rate were 62% and 41%, respectively, in 29 UCHL1-positive patients and 36% and 29%, respectively, in 14 UCHL1-negative patients. CONCLUSIONS: The results of this study suggest that high UCHL1 expression is a strong marker of poor prognosis of endometrial cancer. Furthermore, we suggest that UCHL1 may be involved in the development of distant metastasis in endometrial cancer.

Prevalence of rear seat belt use among pregnant women in a suburban area of Japan.

AIM: The aim of this study was to clarify the prevalence and influencing factors of rear seat belt use among pregnant women. METHODS: Questionnaires were given to 1546 pregnant women who visited obstetrics clinics and hospitals for prenatal checkups from October to December 2013. A total of 1494 pregnant women (96.6%) agreed to participate in this study and completed the questionnaire. RESULTS: Fewer than 20% of the rear-seat passengers 'always' used seat belts before and during pregnancy, whereas a third 'never' used a seat belt before or during pregnancy. There was no significant decrease in seat belt use by rear-seat passengers during compared to before pregnancy. Multivariate analysis revealed that age, knowledge of how to use a seat belt during pregnancy, belief in the compulsory use of a rear seat belt and driver behavioral characteristics before pregnancy were associated with rear seat belt use during pregnancy. CONCLUSIONS: The prevalence of fastening seat belts was substantially low. The provision of information regarding proper seat belt use and its role in protecting the fetus may increase use.

Clinical outcomes of infertility treatment for women with adenomyosis in Japan.

Aim: A multicenter, retrospective survey was conducted in order to investigate the current clinical status of adenomyosis in Japan. Methods: The questionnaires covered the management of infertile women with adenomyosis and the outcomes of infertility treatment in women with adenomyosis. The questionnaires were sent to 1149 facilities in Japan. Results: The data were obtained on 535 infertile women with adenomyosis from 190 facilities. Regarding management, infertility treatment was performed without pretreatment for adenomyosis in 37 facilities, after medication in eight facilities, and after an operation in four facilities. Management policies were not established in 106 facilities. Regarding outcomes, the pregnancy rate was 41.7% and the abortion rate was 29.8%. Eighty-five patients received medication and 89 patients underwent surgery as a pretreatment before infertility treatment, while 361 patients had no pretreatment. In relation to the type of adenomyosis, 162 patients had the focal type and 336 patients had the diffuse type. The pregnancy rate and abortion rate were not affected by pretreatment or the type of adenomyosis. Conclusion: The management policy for infertile women with adenomyosis has not been established. The pregnancy rate of infertility treatment is about 40%. There were no data to suggest that medication or surgery as a pretreatment for adenomyosis increased the pregnancy rate in infertile women.

Complications and outcomes of pregnant women with adenomyosis in Japan.

Purpose: To investigate the impact of adenomyosis on the complications and outcomes of pregnancy in Japan. Methods: We carried out a multicenter retrospective questionnaire survey. A questionnaire regarding pregnancy complications and the outcomes of pregnancy was sent to 725 facilities. Results: Data were obtained on the cases of 272 pregnant women with adenomyosis from 65 facilities. The complications of pregnancy included miscarriage before 12 weeks of pregnancy (14.8%), miscarriage after 12 weeks of pregnancy (9.9%), preterm delivery (24.4%), fetal growth restriction (11.8%), pregnancy-induced hypertension (9.9%), intrauterine infection (7.3%), and cervical incompetency (5.3%). The rates of pregnancy complications in the three groups classified according to pretreatment for adenomyosis (no pretreatment, medication, surgery) did not differ to a statistically significant extent. The rates of miscarriage (>12 weeks) and cervical incompetency increased according to the size of the adenomyosis. The rates of pregnancy-induced hypertension and uterine infection in patients with diffuse-type adenomyosis were higher than that in patients with focal-type adenomyosis. Conclusions: Our results show that the increased size and diffuse type of adenomyosis are associated with adverse pregnancy outcome. We should be aware of the higher incidence of pregnancy-induced hypertension and uterine infection in patients with diffuse-type adenomyosis.

Effect of the molecular targeted drug, erlotinib, against endometrial cancer expressing high levels of epidermal growth factor receptor.

BACKGROUND: The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, erlotinib, has been clinically applied for the treatment of a variety of tumors with EGFR overexpression. A phase II clinical study of erlotinib (NCIC IND-148) for recurrent or metastatic endometrial carcinoma (EC) resulted in an unfavorable result. However, in that study, the expression levels of EGFR were not accurately analyzed. Thus, the aim of this study was to re-examine the efficacy of erlotinib in EC cells by utilizing in vitro and in vivo models. METHODS: Tissue samples obtained from patients histologically diagnosed with EC of the uterine corpus were subjected to immunohistochemistry and RT-PCR to determine the protein and mRNA expression levels of EGFR. Western blot and WST-1 assays of EGFR siRNA-transfected HEC-1A, KLE, and Ishikawa cells were used to evaluate the efficacy of erlotinib in tumor cell lines expressing different EGFR levels. Furthermore, HEC-1A and Ishikawa cells were implanted into athymic mice treated with either erlotinib or trastuzumab. RESULTS: At our institution, 20.9% of endometrial cancer patients with low grade endometrioid histology have been diagnosed as stage III and IV. Immunohistochemical analysis and RT-PCR revealed the presence of significant EGFR and EGFR mRNA expression in low-grade endometrioid carcinoma in comparison with high-grade endometrioid carcinoma. In vitro study, WST-1 assay and Western blot analysis revealed that EGFR expression levels were correlated with tumor cell viability. Erlotinib reduced the proliferation of HEC-1A expressing high levels of EGFR, while trastuzumab showed similar effect in Ishikawa cells dominantly expressing human epidermal growth factor receptor type2 (HER2). In vivo erlotinib decreased tumor growth in mice xenografted with HEC-1A cells, whereas this tumor-growth inhibition was not observed in trastuzumab-treated mice xenografted with Ishikawa cell. CONCLUSIONS: EGF contributed to tumor proliferation in EC cell lines along with EGFR expression in vitro. Erlotinib also demonstrated anti-tumor effects in xenograft mice models. Our results suggest that erlotinib continues to have clinical usefulness in specific cases, after taking into consideration the EGFR expression levels.

Case of radioactive iodine exposure during pregnancy.

A 43-year-old woman (gravida 0, para 0) was diagnosed with thyroid carcinoma and had been receiving radioactive iodine for remnant ablation. Eventually, her pregnant status became apparent; during radiation, she was at 5 gestational weeks. She decided to continue the pregnancy and delivered a boy of 2362 g at 37 gestational weeks. The infant did not present thyroid dysfunction or developmental abnormalities at 2 months of age. The patient was in the early pregnancy stage during radiation, so the fetus did not develop radiation-related damage of the thyroid gland because at this stage, the fetal thyroid does not concentrate iodine. Although the mother had received radioactive iodine during the critical organogenesis period, the fetus did not develop teratogenicity because the radiation was administered at the borderline threshold for teratogenicity. This case suggests the importance of iodine thyroid absorption when considering radiation-related damage to the fetal thyroid gland during early pregnancy.

Annual report of Reproductive Endocrinology Committee, Japan Society of Obstetrics and Gynecology, 2013.

The Japan Society of Obstetrics and Gynecology Reproductive Endocrinology Committee summarizes the activities of each subcommittee below from April 2011 to March 2013. 1. Survey for clinical outcomes of infertility treatment for women with adenomyosis and complications of pregnant women with adenomyosis. 2. Survey for multiple pregnancies after controlled ovarian stimulation in non-assisted-reproductive-technology infertility treatment cycles: population-based study in Japan. 3. Study on the effect of endometriosis management on ovarian reserve.

Role of microRNA-136-3p on the expression of luteinizing hormone-human chorionic gonadotropin receptor mRNA in rat ovaries.

MicroRNAs (miRNAs) are small noncoding RNAs that interact with mRNAs and trigger either translation repression or RNA cleavage of target genes. In this study, we investigated whether miRNA was involved in down-regulation of the luteinizing hormone receptor (LHR) in rat ovaries. An miRNA microarray was used to analyze the overall miRNA expression profile of rat ovaries in association with the down-regulation of LHR mRNA. We found that 23 miRNAs were highly expressed during this period. Combining these results with data from a bioinformatics database, clustering analysis led us to focus on miR-136-3p for further analysis. In both in vivo and in vitro studies, miR-136-3p expression levels were increased at 6 h after human chorionic gonadotropin (hCG) administration, concurrent with down-regulation of LHR mRNA. Moreover, transfection of cultured granulosa cells with miR-136-3p resulted in a significant decrease in LHR mRNA levels in comparison with those of cells transfected with negative control. In contrast, transfection with a miR-136-3p inhibitor increased LHR mRNA levels. Finally, cotransfection of granulosa cells with a miR-136-3p inhibitor and a reporter vector containing the 3'-untranslated region (UTR) of LHR mRNA and Renilla luciferase coding sequence revealed that miR-136-3p bound directly to the 3'-UTR of LHR mRNA. These data demonstrated that miR-136-3p participated in the down-regulation of LHR mRNA by binding directly to LHR mRNA.

Glucose-regulated protein, 78-kilodalton is a modulator of luteinizing hormone receptor expression in luteinizing granulosa cells in rats.

Glucose-regulated protein, 78-kilodalton (GRP78) is a molecular chaperone that exists in the endoplasmic reticulum and is involved in the assembly, transportation, and folding of proteins. Previously, GRP78 was reported to associate with gonadotropin receptors. However, little is known about how GRP78 is involved in the regulation of luteinizing hormone receptor (LHR). Thus, in this study, we investigated the significance of GRP78 for the induction of LHR in rat luteinizing granulosa cells. Western blot analysis of rat LHR expressed in HEK293 cells revealed that the protein levels of LHR were increased, depending on the increment of GRP78 protein. In both in vivo and in vitro experiments, the GRP78 mRNA level peaked while LHR mRNA was down-regulated by human chorionic gonadotropin (hCG). To examine the time-dependent localization of GRP78 in vivo, immunohistochemistry was performed. GRP78 was expressed mainly in granulosa cells, and the GRP78 protein peaked 18 h after the ovulatory dose of hCG injection in equine chorionic gonadotropin-primed immature rats. To ascertain the role of GRP78 in LHR after down-regulation, small interfering GRP78 was transfected to cultured rat granulosa cells, demonstrating that knockdown of the GRP78 protein level impaired the recovery of cell surface LHR from down-regulation that negatively affected progesterone synthesis. Moreover, luciferase assays showed that CRE mediated the hCG-induced promoter activity of GRP78 in rat luteinizing granulosa cells. These results reveal a novel mechanism of LHR by GRP78 in the early stage of corpus lustrum formation, which may be an important factor in the recovery of LHR after the down-regulation.

GRP78 induced by estrogen plays a role in the chemosensitivity of endometrial cancer.

OBJECTIVE: Molecular chaperone 78 kDa glucose-regulated protein (GRP78) is a residential protein in the endoplasmic reticulum (ER) that is induced by an unfolded-protein response triggered under many kinds of stress against a cell. GRP78 is also known to act as an anti-apoptotic factor by protecting ER-stress-induced cell death. In this study, we examined the significance of GRP78 expression in endometrial cancer. METHODS: Tissue samples obtained from patients with a diagnosis of enodometrial cancer were subjected to immunohistochemistry and RT-PCR to determine protein and mRNA expression levels of GRP78 and estrogen receptor α. We used Western blot and RT-PCR to examine whether estrogen induced GRP78 expression in cancer cell lines. Western blots and MTT assays of GRP78 siRNA transfected Ishikawa and HHUA cells were used to demonstrate whether GRP78 is involved in chemoresistence. RESULTS: GRP78 was highly expressed in well and moderately differentiated endometrial carcinoma. Estrogen induced GRP78 expression, which was correlated with cell viability and resistance to paclitaxel and cisplatin. Western blot analysis indicated that active caspase-3 and the 85-kDa protein poly (ADP-ribose) polymerase (PARP) were increased by incubation with either paclitaxel or cisplatin, suggesting that the apoptotic pathway was involved in cancer-drug-induced cell death. CONCLUSIONS: These results may open up a novel therapeutic strategy for endometrial cancer: namely, the targeting of GRP78 to sensitize the tumor cell to chemotherapy.

Lymphangioleiomyomatosis suspected to be a gynecologic disease.

Lymphangioleiomyomatosis (LAM) is a rare, systemic disorder that predominantly affects women. Although patients with LAM mostly present with pulmonary symptoms, some patients may present initially with extrapulmonary symptoms. We present a case of a 30-year-old Japanese female with abdominal pain during menstrual periods was suspected of having ovarian cancer due to exaggerated ascites observed at a local clinic. Subsequently, she was transferred to our hospital for further investigations, and was diagnosed with LAM. Three years after diagnosis, she had a girl by cesarean section to avoid the progression of pulmonary LAM by vaginal delivery. The patient is undergoing follow-up treatment with the administration of gonadotropin-releasing hormone-analog. Though LAM is rare, gynecologists should know about it because it may occur with gynecological symptoms in young women.

SAP-1 is a microvillus-specific protein tyrosine phosphatase that modulates intestinal tumorigenesis.

SAP-1 (PTPRH) is a receptor-type protein tyrosine phosphatase (RPTP) with a single catalytic domain in its cytoplasmic region and fibronectin type III-like domains in its extracellular region. The cellular localization and biological functions of this RPTP have remained unknown, however. We now show that mouse SAP-1 mRNA is largely restricted to the gastrointestinal tract and that SAP-1 protein localizes to the microvilli of the brush border in gastrointestinal epithelial cells. The expression of SAP-1 in mouse intestine is minimal during embryonic development but increases markedly after birth. SAP-1-deficient mice manifested no marked changes in morphology of the intestinal epithelium. In contrast, SAP-1 ablation inhibited tumorigenesis in mice with a heterozygous mutation of the adenomatous polyposis coli gene. These results thus suggest that SAP-1 is a microvillus-specific RPTP that regulates intestinal tumorigenesis.

Plasma adrenomedullin levels during multiple pregnancy.

BACKGROUND: To estimate the normal level of adrenomedullin (AM) during multiple pregnancy. METHODS: The study population consisted of 5 women with normal cycles, 130 women with normal pregnancy between 6 and 40 weeks of gestation, 93 women with twin pregnancy and 42 women with triplet pregnancy. RESULTS: Total AM concentration in the first trimester (13.7 +/- 0.58 fmol/ml), second trimester (26.8 +/- 1.13 fmol/ml) and third trimester (37.8 +/- 1.32 fmol/ml) in pregnant women was significantly higher than that in nonpregnant women (8.0 +/- 0.71 fmol/ml). In each trimester, the maternal plasma concentrations of triplet-pregnant women were significantly higher than in twin and singleton-pregnant women. Umbilical venous AM levels (29.9 +/- 2.63 fmol/ml) were higher than umbilical arterial AM (20.2 +/- 2.04 fmol/ml). CONCLUSION: Since alterations in the AM concentration in maternal plasma may mediate compensatory vascular responses in the uterine circulation, it might be useful to know the normal level of AM during multiple pregnancy in order to detect abnormalities during multiple pregnancy.

Effect of estrogen on the expression of luteinizing hormone-human chorionic gonadotropin receptor messenger ribonucleic acid in cultured rat granulosa cells.

Estrogen has been considered to enhance FSH actions in the ovary, including the induction of the LH receptor (LHR). In this study, we elucidated the mechanism underlying the effect of estrogen on the induction of LHR by FSH in rat granulosa cells. Estradiol clearly enhanced the FSH-induced LHR mRNA increase in a time- and dose-dependent manner, with a maximum increase of approximately 3.5-fold at 72 h, compared with the level of LHR mRNA solely induced by FSH. We then investigated whether the effect of estrogen on LHR mRNA was due to increased transcription and/or altered mRNA stability. A luciferase assay with the plasmid containing the LHR 5'-flanking region did not show that estradiol increased the promoter activity induced by FSH. In contrast, the decay curves for LHR mRNA showed a significant increase in half-life with FSH and estradiol, suggesting that the increased stability of LHR mRNA is at least responsible for the regulation of LHR mRNA by estrogen. Recently mevalonate kinase (Mvk) was identified as a trans-factor that binds to LHR mRNA and alters LHR mRNA stability in the ovary. We found that estradiol, with FSH, decreased Mvk mRNA levels in rat granulosa cell culture, resulting in up-regulation of LHR mRNA that was inversely correlated to Mvk mRNA expression. Furthermore, the augmentation of FSH-induced LHR expression in the presence of estrogen was erased with the overexpression of Mvk by transient transfection. Taken together, these data indicate that LHR mRNA is up-regulated due to increased stability when estrogen negatively controls Mvk.

Expression of an activated mammalian target of rapamycin in adenocarcinoma of the cervix: A potential biomarker and molecular target therapy.

Alterations of the Akt/mTOR pathway have been observed in numerous types of cancer, thus this pathway represents an exciting new target for molecular therapeutics. We investigated the expression of activated Akt (p-Akt) and mTOR (p-mTOR) in patients with adenocarcinoma of the cervix and the involvement of the p-Akt/p-mTOR pathway in response to combination of inhibitor agents, rapamycin and LY294002, with conventional therapy, cisplatin, in vitro. Immunohistochemistry analysis of p-Akt and p-mTOR was conducted in 26 patients with adenocarcinoma of the cervix. Western blot analysis was performed to determine the protein expression involved in response to chemotherapy in cervical cancer cell lines. The results showed that p-Akt and p-mTOR were identified in 50% and 53.8% of adenocarcinoma of the cervix. The expression of p-mTOR was a significant independent marker for prognosis. A significant correlation between p-Akt and p-mTOR was observed. There was no correlation between their expressions with any of clinicopathological factors. In the in vitro study, cisplatin at CPI(50) targets both the apoptosis and survival pathway by activating the caspase-cascade; inhibiting Akt, mTOR, p70S6K, and 4EBP1. Combination of rapamycin with cisplatin induced synergistic interaction. On the other hand, combination with LY294002 resulted in either synergistic or antagonistic effect depending on the doses given. Rapamycin pretreatment potentiated cisplatin-induced apoptosis cell death and enhanced blocking of the survival pathway. Overall, the expression of p-mTOR is a significant prognostic marker of adenocarcinoma of the cervix and a potential molecular target for the treatment of cervical cancer. Inhibition of the mTOR pathway contributes to cisplatin-induced apoptosis in cervical cancer cell lines.

HOX cofactors expression and regulation in the human ovary.

BACKGROUND: HOX cofactors enhance HOX binding affinities and specificities and increase HOX's unique functional activities. The expression and the regulation of HOX cofactors in human ovaries are unknown. METHODS: In this study, the expression of HOX cofactors, PBX1, PBX2, and MEIS1/2, were examined by using RT-PCR, immunofluorescence in cultured immortalized human granulosa (SVOG) cells. The distribution of these HOX cofactors in human ovaries was examined by immunohistochemistry. The effects of growth differentiation factor-9 (GDF-9) and follicle-stimulating hormone (FSH) on PBX2 in SVOG cells were investigated by western blot analysis. Binding activities of HOXA7 and PBX2 to the specific sequences in granulosa cells were determined by electrophoretic mobility shift assay (EMSA). RESULTS AND CONCLUSION: In SVOG cells, PBX1, PBX2 and MEIS1/2 were expressed during cell culture. In normal human ovaries, PBX1 and MEIS1/2 were expressed in granulosa cells at essentially all stages of follicular development. These cofactors were expressed in the nuclei of the granulosa cells from the primordial to the secondary follicles, whereas beyond multilayered follicles was observed in the cytoplasm. The co-expression of PBX1 and MEIS1/2 in granulosa cells in normal human ovaries suggested that MEIS1/2 might control PBX1 sublocalization, as seen in other systems. PBX2 was not expressed or weakly expressed in the primordial follicles. From the primary follicles to the preovulatory follicles, PBX2 expression was inconsistent and the expression was found in the granulosa cell nuclei. The PBX2 expression pattern is similar to HOXA7 expression in ovarian follicular development. Furthermore, FSH down-regulated, GDF-9 did not change PBX2 expression, but co-treatment of the granulosa cells with FSH and GDF-9 up-regulated PBX2 expression. These results implicated a role for PBX2 expression in the steroidogenic activities of granulosa cells in humans. Moreover, PBX2 and HOXA7 bound together to the Pbx sequence, but not to the EMX2 promoter sequence, in SVOG cells. Our findings indicate that HOX cofactors expression in normal human ovary is temporally and spatially specific and regulated by FSH and GDF-9 in granulosa cells. HOX proteins may use different HOX cofactors, depending on DNA sequences that are specific to the granulosa cells.

Compartment syndrome with thrombosis of common iliac artery after gynecologic surgery.

BACKGROUND: Compartment syndrome is a potentially devastating complication with possible permanent neuromuscular and kidney damage. CASE: A woman who had undergone radical hysterectomy with pelvic and paraaortic lymphadenectomy was diagnosed with compartment syndrome of the lower left limb. Thrombosis of the left common iliac artery was also found after emergency fasciotomy. CONCLUSION: Arterial thrombosis is less common than deep vein thrombosis during gynecologic operations, but the lithotomy position may cause insufficient arterial circulation in both the pelvis and legs.

Primary hypothyroidism presenting as multiple ovarian cysts in an adult woman: a case report.

A 21-year-old woman was referred because of abdominal pain. On physical examination, her abdomen was distended up to the umbilical region. Ultrasound and computer tomography of the abdomen revealed bilateral multiple ovarian cysts. Laboratory studies revealed increased liver function, total cholesterol and creatine phosphokinase. Further clinical investigations determined that the patient suffered from primary hypothyroidism due to autoimmune thyroiditis. The cysts resolved spontaneously after the simple replacement of a thyroid hormone. Some reports have been published of primary hypothyroidism presenting as ovarian cysts and precocious puberty in prepubertal girls. However, the case presented herein indicates that an ovarian tumor as a result of hypothyroidism may also occur in adult females. To avoid inadvertent surgery to remove an ovarian tumor, it is essential that a patient with multiple ovarian cysts and hypothyroidism be properly managed, as the simple replacement of a thyroid hormone could resolve the ovarian cysts.

Regulation of human luteinizing hormone receptor in the ovary.

The luteinizing hormone receptor (LHR) is essential for elevated levels of progesterone to maintain pregnancy during the first trimester; the maintenance of the expression of LHR is a key factor controlling the duration of luteal function. Therefore, as the expression of LHR is most likely to be regulated by the stability of the receptor mRNA at the luteal phase of the human menstrual cycle, we focused on studies examining the stability of mRNA rather than the production of mRNA. In addition, LHR (exon 9), one of the splice variants of human LHR (hLHR), was cloned in the corpus luteum of a patient with a regular menstrual cycle. The results of Western blots using Percoll gradient fractionation indicated that hLHR formed complexes with hLHR (exon 9), which are transferred to the lysosome, where they are eventually degraded, instead of being translocated from the endoplasmic reticulum to the transducing organelle. These results showed that hLHR (exon 9) caused a reduction in the expression of functional receptor number and affected the signaling condition of wild-type hLHR. As the luteal phase progressed hLHR (exon 9) increased relative to hLHR, demonstrating that hLHR (exon 9) was expressed more than hLHR in the late luteal phase. This work reveals the essential function of the regulatory and structural elements involved in human LH receptor splicing, and that hLHR (exon 9) can negatively control the function of wild-type receptors. Moreover, this finding presented a novel mechanism of regulation of LHR in the human corpus luteum. (Reprod Med Biol 2008; 7: 11-16).