Biomedical subjects

Jun-ichi Akahira

Publications and source records attributed to Jun-ichi Akahira.

12 recordsLinked to original sources

PubMed2007

5Alpha-reductase type 1 and aromatase in breast carcinoma as regulators of in situ androgen production.

Previous in vitro studies demonstrated that bioactive androgen 5alpha-dihydrotestosterone (DHT) exerted antiproliferative effects through an interaction with androgen receptor (AR) in breast carcinoma cells. However, AR status has not been examined in association with DHT concentration in breast carcinoma tissues, and significance of androgenic actions remains unclear in breast carcinomas. Therefore, in our study, we first examined intratumoral DHT concentrations in 38 breast carcinoma tissues using liquid chromatography/electrospray tandem mass spectrometry. Intratumoral DHT concentration was positively associated with 5alpha-reductase type 1 (5alphaRed1), and negatively correlated with aromatase. We then examined clinical significance of AR and 5alphaRed1 status in 115 breast carcinoma tissues by immunohistochemistry. Breast carcinomas positive for both AR and 5alphaRed1 were inversely associated with tumor size or Ki-67. These patients showed significant associations with a decreased risk of recurrence and improved prognosis for overall survival, and the AR / 5alphaRed1 status was demonstrated an independent prognostic factor. Moreover, we examined possible regulation of DHT production by aromatase in in vitro studies. DHT synthesis from androstenedione in MCF-7 cells was significantly inhibited by coculture with aromatase-positive stromal cells, which was significantly reversed by addition of aromatase inhibitor exemestane. These results suggest that intratumoral DHT concentration is mainly determined by 5alphaRed1 and aromatase in breast carcinoma tissues, and antiproliferative effect of DHT may primarily occur in the cases positive for both AR and 5alphaRed1. Aromatase inhibitors may be more effective in these patients, possibly due to increasing local DHT concentration with estrogen deprivation.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

PubMed2005

14-3-3sigma in endometrial cancer--a possible prognostic marker in early-stage cancer.

PURPOSE: We examined expression of 14-3-3sigma, a regulator of cell proliferation, and evaluated its clinical significance in endometrioid endometrial carcinoma. EXPERIMENTAL DESIGN: One hundred three endometrioid endometrial adenocarcinoma cases were examined using immunohistochemistry with archival specimens. We correlated this finding with various clinicopathologic variables, including the status of estrogen receptor, progesterone receptor, and MIB-1 (Ki-57). RESULTS: 14-3-3sigma Immunoreactivity was detected in 78 of 103 (75.3%) of carcinoma cases. No statistically significant correlation was detected between status of 14-3-3sigma and any of clinicopathologic variables examined. There was, however, a statistically significant correlation between loss of 14-3-3sigma expression and adverse clinical outcome of the patients (P = 0.0007). In the early stages of cancer (stages I and II), 14-3-3sigma immunoreactivity was absent in 5 of 10 (50.0%) patients who showed recurrence during follow-up, whereas its absence was detected in only 13 of 68 (19.1%) disease-free patients in the same period. In addition, 14-3-3sigma immunoreactivity was absent in 4 of 5 (80.0%) patients who died, whereas its absence was detected in only 14 of 73 (19.2%) patients who had lived during the same period. Patients whose tumors were negative for 14-3-3sigma were at much greater risk to develop recurrent and/or mortal disease (P = 0.0372 and 0.0067). In multivariate analysis using the Cox proportional hazards model, absence of 14-3-3sigma turned out to be statistically independent risk factor in disease-free survival and overall survival even in patients with early-stage disease (P = 0.0321 and 0.0191). CONCLUSIONS: Results of our study showed that loss or absence of 14-3-3sigma determined by immunohistochemistry may be an important tool to identify endometrial carcinoma cases at high risk of recurrence and/or death, who are otherwise not detected by current clinical and pathologic evaluation, especially in the early stages of the disease. In addition, results of 14-3-3sigma immunohistochemistry in the early stage of endometrial carcinoma could contribute to planning postoperative follow-up and adjuvant therapy.

14-3-3 Proteins↗

PubMed2005

Expression of estrogen-responsive finger protein (Efp) is associated with advanced disease in human epithelial ovarian cancer.

OBJECTIVE: The estrogen-responsive ring finger protein (Efp) gene, one of estrogen receptor (ER) target genes, is considered to be essential for estrogen-dependent cell proliferation. To understand the estrogenic action on ovarian cancer, we studied the relationships between Efp and ERs expressions and the correlations of Efp expression with clinicopathological parameters in epithelial ovarian cancer. METHODS: The protein expressions for Efp, ERalpha and ERbeta were examined by immunoblotting in 12 ovarian cancer cell lines. Efp mRNA expressions were evaluated by quantitative RT-PCR in 12 ovarian cancer cell lines. A total of 100 surgical specimens diagnosed as epithelial ovarian cancer were examined immunohistochemically using antibodies for Efp, ERalpha and ERbeta. RESULTS: Efp protein was detected in 8 out of 12 cell lines. In Efp protein-positive cell lines, Efp mRNA was expressed higher than that in negative (P=0.021). All of the Efp protein-positive cell lines simultaneously expressed either ERalpha or ERbeta protein. By immunohistochemical staining, Efp immunoreactivity was detected in 63 out of 100 ovarian cancer specimens and positive signals were in the cytoplasm of carcinoma cells. There were significant correlations between Efp and ERalpha, ERbeta immunoreactivity (Efp and ERalpha, P=0.022; Efp and ERbeta, P=0.032). Efp expression was significantly higher in a subgroup with serous adenocarcinoma (P=0.010) and with advanced disease (P=0.026). No significant relationship was detected between Efp immunoreactivity and overall survival. CONCLUSION: The expression of Efp was detected in human epithelial ovarian cancer and high expression of Efp was correlated with advanced disease and serous adenocarcinoma, and ERs status.

Adenocarcinoma↗

PubMed2005

Immunolocalization of nuclear transcription factors, DAX-1 and Ad4BP/SF-1, in human common epithelial ovarian tumors: correlations with StAR and steroidogenic enzymes in epithelial ovarian carcinoma.

Intratumoral steroidogenesis is considered to play important roles in the biologic behavior of common epithelial ovarian carcinoma. Recent studies have demonstrated the important roles of Ad4BP/SF-1 and DAX-1 in regulation of steroidogenesis. In this study, we evaluated DAX-1, Ad4BP/SF-1, StAR, and steroidogenic enzyme expressions and their correlations in epithelial ovarian carcinomas to evaluate the possible roles of these factors in regulation of intratumoral steroid metabolism and/or production. Immunolocalization of DAX-1, Ad4BP/SF-1, StAR, and steroidogenic enzymes were examined in 90 epithelial ovarian carcinomas. mRNA expression of these proteins was evaluated using real-time polymerase chain reaction (PCR) in 23 cases for further characterization. DAX-1 and Ad4BP/SF-1 immunoreactivity was detected predominately in the nuclei of tumor cells, whereas that of StAR and steroidogenic enzymes was present in the cytoplasm. We detected a significant positive correlation between StAR and steroidogenic enzymes immunoreactivity and Ad4BP/SF-1 and statistically inversed correlation with DAX-1. A positive statistical correlation was detected between intratumoral stromal Ad4BP/SF-1 immunoreactivity and clinicopathologic parameters of carcinoma patients. Results of real-time PCR analysis were correlated with those of immunohistochemical studies. The status of intratumoral DAX-1, Ad4BP/SF-1, and StAR and steroidogenic enzymes in epithelial cells and intratumoral stromal cells of epithelial ovarian carcinoma may contribute in the progression and/or aggressiveness of these tumors.

Biomarkers, Tumor↗

PubMed2005

StAR and progesterone producing enzymes (3beta-hydroxysteroid dehydrogenase and cholesterol side-chain cleavage cytochromes P450) in human epithelial ovarian carcinoma: immunohistochemical and real-time PCR studies.

Steroidogenic acute regulatory protein (StAR), P450 side-chain cleavage enzyme (P450scc) and 3 beta-hydroxysteroid dehydrogenase enzyme (3beta-HSD) are all involved in the transport of cholesterol and production of progesterone. In situ production of sex steroids including progesterone have been considered to play important roles in pathogenesis and/or development of common epithelial ovarian carcinomas. In this study, StAR, P450scc, and 3beta-HSD were immunolocalized in 100 cases of ovarian carcinoma and results were then correlated with clinicopathological and prognostic parameters of individual patients including status of progesterone receptor (PR) in tumor cells. Results of immunohistochemistry were further characterized by real-time PCR analysis in 20 cases of epithelial ovarian carcinomas in which frozen tissues were available for examination. StAR, P450scc, and 3beta-HSD immunoreactivity was detected predominately in the cytoplasm of carcinoma cells. Results of real-time PCR analysis were correlated with those of immunohistochemical studies. StAR, P450scc, and 3beta-HSD H scores demonstrated significant inversed statistical correlation with FIGO stage, residual size of the tumor, and Ki67 LI. A positive statistically significant correlation was detected between StAR H score and PR-B LI. Multivariate statistical analysis demonstrated that the status of intratumoral StAR, FIGO stage, and residual tumor size all turned out to be independent prognostic factors for the clinical outcome of the patient. The presence of StAR, a cholesterol transporter for steroidogenesis in human epithelial ovarian carcinoma, may reflect the ability of these tumors to produce progesterone in situ that could influence biological behavior of these tumors, especially through progesterone dependent inhibition of tumor cell proliferation.

17-Hydroxysteroid Dehydrogenases↗

PubMed2005

Orphan nuclear receptor DAX-1 in human endometrium and its disorders.

DAX-1 (dosage-sensitive sex reversal adrenal hypoplasia congenita critical region on the X chromosome gene 1) is a recently characterized member of the orphan nuclear receptor family. DAX-1 functions as a global negative regulator of steroid hormone production. It inhibits adrenal 4 binding protein (Ad4BP)/steroidogenic factor-1 (SF-1) pathway-dependent P450arom expression in cultured human endometriotic stromal cells and acts as a corepressor for estrogen receptors (ER). In this study we first examined the localization of DAX-1 in 46 normal cycling endometria, 36 cases of endometrial hyperplasia and 103 cases of endometrial carcinoma by using immunohistochemistry to elucidate the possible involvement of DAX-1 and its correlation to the status of Ad4BP/SF-1, a universal transcription factor of steroidogenesis. We then evaluated DAX-1 mRNA expression, using quantitative reverse transcription-polymerase chain reaction for DAX-1 in 33 cases of endometrial carcinoma for further characterization. We subsequently correlated these findings with various clinicopathological parameters of the cases. Ad4BP/SF-1 immunoreactivity was not detected in any human endometria examined. A significant inverse correlation was detected between the status of DAX-1 immunoreactivity and histological grade (P = 0.0003) in endometrial carcinoma. The labeling index (LI) values of DAX-1 in normal endometrium during the secretory phase (P < 0.0001) and hyperplasia (P < 0.0001) were significantly higher than that of carcinoma. No significant correlations were detected between DAX-1 immunoreactivity and amounts of aromatase mRNA. There was a statistically significant positive correlation between DAX-1 and ERalpha (P = 0.006) and ERbeta LI (P < 0.001). These findings suggest that DAX-1 may inhibit the proliferation and progression of endometrial carcinoma through inhibition of estrogenic actions, possibly by interacting with ER present in carcinoma cells, rather than regulating in situ steroidogenesis.

Adrenal Glands↗

PubMed2004

Decreased expression of 14-3-3 sigma is associated with advanced disease in human epithelial ovarian cancer: its correlation with aberrant DNA methylation.

PURPOSE: In this study, we examined the promoter methylation status and expression of 14-3-3 sigma and evaluated its clinical significance in epithelial ovarian cancer. EXPERIMENTAL DESIGN: Twelve ovarian cancer cell lines; 2 ovarian surface epithelial cell lines; and 8 normal, 8 benign, 12 borderline, and 102 ovarian cancer tissues were examined. Methylation-specific PCR, quantitative reverse transcription-PCR, and immunohistochemistry were used to evaluate methylation status and expression of 14-3-3 sigma gene and protein. RESULTS: Among the 12 ovarian cancer cell lines, the presence of a methylated band was detected in seven cell lines. Median values of relative 14-3-3 sigma gene expression in cancers with methylation (3.27) were significantly lower than those without methylation (16.4; P < 0.001). Treatment of 5-aza-2'-deoxycitidine resulted in the demethylation of the promoter CpG islands and reexpression. All of the normal, benign, and borderline tissues were positive for 14-3-3 sigma protein, and in ovarian cancer tissues, 73.5% (75 of 102) were positive for 14-3-3 sigma protein and was almost consistent with methylation status. Negative immunoreactivity of 14-3-3 sigma was significantly correlated with high age and serous histology, high-grade, advanced-stage residual tumor of >2 cm, high serum CA125, high Ki-67 labeling index, and positive p53 immunoreactivity. 14-3-3 sigma immunoreactivity was significantly associated with overall survival (P = 0.0058). CONCLUSIONS: Our findings suggest that 14-3-3 sigma is inactivated mainly by aberrant DNA methylation and that it may play an important role in the pathogenesis of epithelial ovarian cancer.

14-3-3 Proteins↗

PubMed2004

Primary vaginal adenosarcoma with sarcomatous overgrowth.

BACKGROUND: Primary vaginal adenosarcomas are extremely rare, and typical adenosarcomas are of low malignancy. However, aggressive forms with sarcomatous overgrowth have been reported, those appear to have a poor prognosis. CASE: A 52-year-old woman who had undergone prior surgery for uterine leiomyoma and an ovarian cyst (total abdominal hysterectomy and left salpingo-oophorectomy) presented 10 years later with a rapidly enlarging tumor arising from the vaginal cuff. Repetitive biopsy samples revealed a mixture of benign epithelial gland and malignant stromal components with periglandular stromal hypercellularity and sarcomatous overgrowth. A histological diagnosis of mullerian adenocarcinoma was made. The patient died from recurrent disease 9 months after surgery. CONCLUSION: Regardless of primary focus, adenosarcoma with sarcomatous overgrowth is associated with postoperative recurrence and a fatal outcome.

Adenosarcoma↗

PubMed2004

Promoter methylation status and expression of TMS1 gene in human epithelial ovarian cancer.

Gene silencing associated with aberrant DNA methylation of promoter CpG islands is one mechanism through which tumor suppressor genes are inactivated in human cancers. TMS1 (target of methylation-induced silencing) is a CpG island-associated gene that functions in the regulation of apoptosis. In this study, we examined the DNA methylation status of the TMS1 promoter in ovarian cancer cell lines and tissues by methylation-specific PCR (MSP) and its mRNA expression by reverse transcription and quantitative PCR. Aberrant methylation of TMS1 was present in 7/12 ovarian cancer cell lines and 8/20 primary ovarian cancer tissues. The median value of relative TMS1 gene expression in cancers with methylation (0.15) was significantly lower than that in cancers without methylation (13.9) (P < 0.001). The expression of the TMS1 gene was relatively high (48.5) in the normal ovarian cDNA library. TMS1 gene expression was restored by treatment with the demethylating agent 5-aza-2'-deoxycitidine in the OV90 cell line, which lacks the TMS1 transcript. Our results suggest that aberrant methylation of TMS1 may play a role in the pathogenesis of ovarian cancer.

CARD Signaling Adaptor Proteins↗

PubMed2003

Prognostic significance of second-look laparotomy for surgically confirmed early-stage epithelial ovarian cancer: a multicenter retrospective study.

BACKGROUND: In the present study, we conducted a multicenter retrospective analysis to elucidate the prognostic significance of second-look laparotomy (SLL) in early-stage epithelial ovarian cancer that was confirmed by complete surgical exploration. METHODS: In July 2001, 12 Japanese institutions received questionnaires regarding patients with early-stage epithelial ovarian cancer and SLL. Eligibility criteria included patients with stage I or II epithelial ovarian cancer who were surgically diagnosed between January 1988 and December 1997. Data were collected regarding age, performance status, tumor histologic subtype, stage, preoperative carbohydrate antigen (CA) 125 level, results of SLL if performed, recurrence, disease-free survival, and overall survival. Survival analyses and comparisons were performed by univariate methods. RESULTS: There were 87 patients who met the eligibility criteria. There were no significant differences in the backgrounds of patients who had had SLL ( n = 30) and the non-SLL group ( n = 57). Of the 30 SLL-group patients, 28 had negative SLL findings and 2 had positive findings. Six and 5 patients in the SLL group and the non-SLL group, respectively, had recurrence ( P = 0.177), and 4 patients in the SLL group had a recurrence after "negative" SLL findings. There was no significant difference between the two groups for either overall ( P = 0.73) or disease-free survival ( P = 0.273). On univariate analysis, only clear-cell histology was associated with a poor prognosis in early-stage epithelial ovarian cancer ( P = 0.031). CONCLUSION: SLL is not beneficial for early-stage epithelial ovarian cancer. More favorable outcomes will be achieved for early-stage patients with the improvement of treatment for clear-cell adenocarcinoma.

Adult↗

PubMed2003

Nuclear receptor DAX-1 in human common epithelial ovarian carcinoma: an independent prognostic factor of clinical outcome.

DAX-1 is a member of the nuclear receptor superfamily and is thought to be involved in the regulation of steroidogenesis. Its expression has been detected primarily in endocrine neoplasms such as adrenocortical as well as pituitary tumors in human, but its biological roles have not been examined well in sex steroid-dependent neoplasms. The aim of this study is to detect the expression of DAX-1 in common epithelial ovarian carcinomas in order to evaluate its possible biological significance. DAX-1 immunoreactivity was examined using immunohistochemistry. The correlation between the status of DAX-1 immunoreactivity and clinicopathological parameters and disease-free survival of the patients in a series of 60 cases of common epithelial ovarian carcinoma was examined. The status of DAX-1 immunoreactivity was evaluated using H score. DAX-1 immunoreactivity was widely detected in the nuclei of common epithelial ovarian carcinoma cells. There was a significant positive correlation between DAX-1 immunoreactivity and clinical staging (P = 0.0241), tumor grade (P = 0.0115), the residual size of the tumor (P = 0.0014) and Ki-67 labeling index (P = < 0.0001). In univariate survival analysis, a significant association was detected between DAX-1 immunoreactivity and shortened patient survival (P = 0.0157). Other significant prognostic parameters were clinical stage, residual size of tumor and Ki-67. In multivariate analysis, DAX-1 immunoreactivity, clinical stage, residual size of tumor and Ki-67 all turned out to be independent prognostic factors for shortened survival. In conclusion, DAX-1 immunoreactivity is considered to be a new independent marker of poor prognosis or adverse clinical outcome in patients with epithelial ovarian carcinoma, possibly through altering in situ steroids production.

Adenocarcinoma, Clear Cell↗

PubMed2002

Expression of androgen receptor and 5alpha-reductases in the human normal endometrium and its disorders.

Androgen metabolism and actions are considered to play a very important role in the development and progression of the normal human endometrium and its disorders. Details regarding androgen actions in these tissues, however, have not been well studied. We first immunolocalized the androgen receptor (AR) and 5alpha-reductases, which catalyze the conversion of testosterone to the bioactive and potent androgen, 5alpha-dihydrotestesterone (DHT), in 18 normal cycling human endometria, 27 endometrial hyperplasia and 46 endometrioid endometrial adenocarcinomas. We also examined the mRNA expression of AR and 5alpha-reductases in 7 cases of endometrioid endometrial adenocarcinomas using reverse transcription polymerase chain reaction (RT-PCR). In the normal human endometrium, AR was immunolocalized predominantly in stromal cells of the proliferative phase of the menstrual cycle and in epithelial cells of the secretory phase, whereas 5alpha-reductase types 1 and 2 immunoreactivities were detected in the cytoplasm of epithelial cells but not in stromal cells throughout all phases of the menstrual cycle. In endometrial hyperplasia, the median labeling index (LI) for AR was 48.1%, whereas positive immunostaining for 5alpha-reductase Type 1 and Type 2 was detected in only 1 case. In endometrial carcinoma, AR immunoreactivity was detected in the nuclei of carcinoma cells and the number of positive cases was 39/44 (88.6%). Median LI for AR was 36.1%. Immunoreactivity for 5alpha-reductase Type 1 and Type 2 was detected in the cytoplasm of carcinoma cells and the number of positive cases was 37/44 cases (84.1%) and 34/44 (77.3%) for 5alpha-reductase Types 1 and 2, respectively. A significant positive correlation was detected between 5alpha-reductase Type 1 and Type 2 immunoreactivity (p < 0.001). AR LI was not correlated with the presence or absence of Type 1 and Type 2 5alpha-reductases. Results from our RT-PCR studies were consistent with those of immunohistochemistry. These results suggest that DHT may play more important roles than testosterone in the regulation of androgen action in endometrial cancer and normal human endometrium, especially in the secretory phase, in which both AR and 5alpha-reductase are increased. Androgenic actions may be also regulated predominantly by serum testosterone and not by DHT in endometrial hyperplasia because of the absence of 5alpha-reductases in the site of its actions.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗