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Takayuki Enomoto

Publications and source records attributed to Takayuki Enomoto.

At least 19 recordsLinked to original sources
PubMed2006

Prognostic significance of p53 mutation in suboptimally resected advanced ovarian carcinoma treated with the combination chemotherapy of paclitaxel and carboplatin.

The prognostic significance of p53 mutation, microsattelite instability and DNA mismatch protein hMLH1 expression in suboptimally resected advanced ovarian carcinoma treated with the combination chemotherapy of paclitaxel and carboplatin was evaluated. The overall combination chemotherapy response rate and the complete remission rate were significantly higher among patients with mutant p53 tumors than those with wild-type p53 tumors (35/42 (83%) vs. 32/58 (55%); P=0.003 and 18/42 (43%) vs. 16/58 (28%); P=0.03, respectively). This tendency apparently existed in non-serous carcinoma, but not in serous carcinoma. Univariate analysis showed that the risk of death due to disease and risk of progression was significantly lower among patients with p53 mutation (P=0.0357 and 0.0281, respectively). However, the presence of microsattelite instability or loss of hMLH1 expression was not associated with either the clinical response or prognosis. Determining p53 mutational status can be useful in predicting therapeutic response to drugs in ovarian carcinoma, especially in non-serous tumors.

Adenocarcinoma, Clear Cell↗
PubMed2005

Mutational analysis of TP53 and p21 in familial and sporadic ovarian cancer in Japan.

OBJECTIVE: To investigate whether somatic mutations in cell cycle checkpoint genes, TP53 and p21, are involved in the development of ovarian cancer with or without BRCA1 germline mutation. METHODS: We analyzed somatic genetic alterations of TP53 and p21 in 46 ovarian cancer patients with BRCA1 germline mutations and 93 sporadic patients, using direct sequencing for the entire coding sequences in TP53 and p21. RESULTS: TP53 somatic mutations were detected in 25 of the 46 BRCA1 cases and 40 of the 93 sporadic cases (54.3% vs. 43.0%). In contrast, p21 somatic mutations were detected in 1 of the 46 BRCA1 cases and 2 of the 93 sporadic cases (2.2% vs. 2.2%). TP53 mutations in sporadic cases more frequently occurred in exons 6-11 than those in cases with germline BRCA1 mutations (84.4% vs. 56.3%: P = 0.013). The proportion of sporadic cases with TP53 mutations in non-serous tumors (e.g. endometrioid, clear cell, or mucinous) was significantly lower than that in serous tumors (18.5% vs. 53.0%: P = 0.0038). However, there was no significant difference between the proportion of BRCA1 cases with TP53 mutation in non-serous and in serous tumors (37.5% vs. 57.9%). CONCLUSIONS: Our results suggest that somatic mutation of TP53 plays less of a role in the carcinogenesis of sporadic non-serous tumors than in that of sporadic serous tumors or BRCA1-related tumors. Furthermore, p21 somatic mutation appears to be less involved in the development of ovarian cancer than TP53 somatic mutation.

Adult↗
PubMed2005

B7-H4 overexpression in ovarian tumors.

OBJECTIVES: Despite great advances in therapeutic management, the mortality rate for ovarian cancer has remained relatively stable over the past 50 years. This study was designed to evaluate the expression of B7-H4 protein, recently identified as a potential molecular marker of breast and ovarian cancer by quantitative PCR analysis, in benign tumors, tumors of low malignant potential and malignant tumors of the ovary. METHODS: Archival formalin-fixed tissue blocks from serous, mucinous, endometrioid and clear cell ovarian tumors were evaluated by immunohistochemistry for the distribution of B7-H4 expression, and staining intensity was measured by automated image analysis. Univariate analyses were used to test for statistically significant relationships. RESULTS: B7-H4 cytoplasmic and membranous expression was detected in all primary serous (n = 32), endometrioid (n = 12), and clear cell carcinomas (n = 15), and in all metastatic serous (n = 23) and endometrioid (n = 7) ovarian carcinomas. By contrast, focal B7-H4 expression was detected in only 1/11 mucinous carcinomas. The proportion of positive cells and median staining intensity was greater in serous carcinomas than in serous cystadenomas or serous tumors of low malignant potential, and the differences were statistically significant (P < 0.0001 and P = 0.034, respectively). The median staining intensity was also significantly greater in endometrioid carcinomas than in endometriosis (P = 0.005). CONCLUSIONS: The consistent overexpression of B7-H4 in serous, endometrioid and clear cell ovarian carcinomas and the relative absence of expression in most normal somatic tissues indicates that B7-H4 should be further investigated as a potential diagnostic marker or therapeutic target for ovarian cancer.

Adenocarcinoma, Clear Cell↗
PubMed2005

Overexpression of LAMP3/TSC403/DC-LAMP promotes metastasis in uterine cervical cancer.

LAMP3 (DC-LAMP, TSC403, CD208) was originally isolated as a gene specifically expressed in lung tissues. LAMP3 is located on a chromosome 3q segment that is frequently amplified in some human cancers, including uterine cervical cancer. Because two other members of the LAMP family of lysosomal membrane glycoproteins, LAMP1 and LAMP2, were previously implicated in potentially modulating the interaction of vascular endothelial and cancer cells, we hypothesized that LAMP3 might also play an important part in metastasis. To clarify the metastatic potential of LAMP3 in cervical cancers, we transfected a LAMP3 expression vector into a human uterine cervical cancer cell line, TCS. In an in vitro invasion assay, the migration of LAMP3-overexpressing TCS cells was significantly higher than in control TCS cells. In an in vivo metastasis assay, distant metastasis was detected in 9 of 11 LAMP3-overexpressing TCS cell-injected mice and in only 1 of 11 control mice. Histologic study showed that LAMP3-overexpressing cells readily invaded into the lymph-vascular space. In clinical samples, quantitative real-time reverse transcription-PCR (RT-PCR) analyses showed that LAMP3 mRNA was significantly up-regulated in 47 of 47 (100%) cervical cancers and in 2 of 15 (13%) cervical intraepithelial neoplasias, compared with a low level of LAMP3 mRNA expressed in normal uterine cervixes. Interestingly, high LAMP3 expression was significantly correlated with the overall survival of patients with stage I/II cervical cancers. These findings indicate that LAMP3 overexpression is associated with an enhanced metastatic potential and may be a prognostic factor for cervical cancer.

Animals↗
PubMed2005

Altered protein expression in endometrial carcinogenesis.

We have discovered several protein biomarkers that are altered during carcinogenesis of the human uterine endometrium. Proteins prepared from 19 endometrial carcinomas (Group A), and 20 normal endometria obtained from benign gynecological conditions (Group B), were investigated by Surface Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS). Two proteins, EC1 and EC2, were consistently expressed differentially. EC1 had an increased level of expression in carcinomas (P<0.001), while EC2 was expressed at a lower level (P=0.004). The isoelectric points of EC1 and EC2 were approximately pH 5.0 and 7.0, respectively. These proteins are thus potential biomarkers for detection of endometrial carcinoma.

Adult↗
PubMed2005

Mutational analysis of the estrogen receptor-alpha gene in familial ovarian cancer.

AIM: The genetic region of 6q25 containing the estrogen receptor-alpha (ER-alpha) gene is lost in a significant number of ovarian tumors. The aim of this study was to identify how inherited variation in the ER-alpha gene contributes to susceptibility to familial ovarian cancer. METHODS: DNA obtained from 18 cases of familial ovarian cancer without mutation of the BRCA1 and BRCA2 genes, 20 cases with BRCA1 mutation, 20 cases of sporadic ovarian cancer, and 19 controls were screened for mutations in the coding region of the ER-alpha gene using direct sequencing. RESULTS: Two germline missense variants at codons 307 [GCC(Ala)-->TCC(Ser)] and 347 [ACC(Thr)-->TCC(Ser)] were detected in two unrelated cases with BRCA1 mutation, but not in all other cases tested. Three polymorphisms in codon 10 [TCT-->TCC(Ser)], codon 325 [CCC-->CCG(Pro)], and codon 594 [ACA-->ACG(Thr)] were identified in this series, and a higher frequency of the allele TCC at codon 10 and a lower frequency of the allele CCG at codon 325 were observed in familial cases without BRCA1 mutation, compared with those in familial cases with BRCA1 mutation, in both the sporadic cases and in the controls. CONCLUSIONS: We could not detect pathogenic mutations of the ER-alpha gene in ovarian cancer cases without BRCA1 mutation. However, association analyses of two polymorphisms suggest that the ER-alpha gene or a gene located close to the ER-alpha locus might be related to susceptibility of familial ovarian cancer without BRCA1 mutation.

Adult↗
PubMed2004

Correlation between p14(ARF)/p16(INK4A) expression and HPV infection in uterine cervical cancer.

The CDKN2A locus on human chromosome 9p21 encodes two tumor suppressors, p14(ARF) and p16(INK4A), which enhance the growth-suppressive functions of the retinoblastoma (Rb) and the p53 proteins, respectively. Conversely, the E6 and E7 oncoproteins of the high-risk human papillomaviruses (HPVs) causally associated with carcinogenesis of the uterine cervix contributes to tumor development by inactivating p53 and Rb. Nevertheless, a correlation between expression of p14(ARF)/p16(INK4A) and HPV infection in uterine cervix is less clear. To clarify this, we examined 25 cervical cancers and 11 normal uterine cervixes. HPV was detected in 21 of 25 cervical cancers (84%) and their subtype was determined by PCR-RFLP. Quantitative real-time RT-PCR assays showed overexpression of p14(ARF) mRNA in all 21 HPV-positive cases (100%). p16(INK4A) mRNA was overexpressed in 17 cases of the HPV-positive cases (81%). In four HPV-negative cancers, reduced expression of p14(ARF) mRNA was detected in two cases (50%) and reduced p16(INK4A) mRNA in three cases (75%). Our data indicate that the overexpression of p14(ARF) and p16(INK4A) strongly associates with HPV-positive cervical cancers and that reduced expression of p14(ARF) and p16(INK4A) correlates with HPV-negative cervical cancers. These findings may indicate that impaired p14(ARF) and p16(INK4A) mRNA expression contribute to tumor development in HPV-negative cervical cancers by failure to support p53 and Rb instead of their inactivation by HPV E6 and E7.

Carcinoma, Squamous Cell↗
PubMed2004

Analysis of clonality and HPV infection in benign, hyperplastic, premalignant, and malignant lesions of the vulvar mucosa.

To elucidate the pathogenesis of vulvar carcinomas, we studied clonality and human papillomavirus (HPV) infection in vulvar epithelial diseases. Monoclonal composition was demonstrated in all 9 invasive tumors (squamous cell carcinoma [SCC], 6; basal cell carcinoma, 1; malignant melanoma, 2), 15 of 20 cases of vulvar intraepithelial neoplasia (VIN), 7 of 9 cases of Paget disease, 2 of 6 cases of lichen sclerosus (LS), and 2 of 3 cases of squamous cell hyperplasia (SCH); high-risk type HPV was revealed in 5 of 6 SCCs and 17 of 20 VINs. These observations might imply that a subset of cases of LS and SCH result from a neoplastic proliferation, similar to VINs but not related to infection with high-risk type HPV. In 1 case of SCC with concurrent VIN 3 in an adjacent lesion, both lesions showed the same pattern of X chromosome inactivation and the presence of HPV-16 in episomal and integrated forms, suggesting that monoclonal expansion triggered by high-risk type HPV integration is an early event for carcinogenesis of HPV-associated SCC.

Carcinoma in Situ↗
PubMed2004

Cisplatin enhances the p53-independent apoptosis induced by a topoisomerase I inhibitor (CPT-11) in the lens epithelial tumors in transgenic mice.

We reported that CPT-11 could induce apoptosis in mouse lens epithelial tumors when it was administered to pregnant alphaT3 mice which developed epithelial cell carcinoma in situ in the lens in the perinatal period. p53-deficient alphaT3 mice were generated to analyze the influence of p53 status on tumor cells under combined chemotherapy. On the 16-18th gestational day, alphaT3 received a single i.p. administration of both CPT-11 and Cisplatin, and fetal lens epithelial tumors were examined two days later. Apoptosis in the p53-wild-type alphaT3 tumors was observed in a Cisplatin dose-dependent manner. In addition, it was found that Cisplatin augmented CPT-11-induced p53-independent apoptosis in p53-deficient alphaT3 mice.

Animals↗
PubMed2003

Genetic alterations in ovarian carcinoma: with specific reference to histological subtypes.

Multiple genetic changes including activation of proto-oncogenes and inactivation of tumor suppressor gene are involved in the development of human ovarian cancer. We describe such genetic alterations with specific reference to histological subtypes. K-ras activation is specific for mucinous tumors including adenomas. Borderline tumors and carcinomas, suggesting that K-ras activation may be associated with the mucinous differentiation rather than malignant transformation. Inactivation of p53 is detected in 30-40% of ovarian carcinoma. Mutations are more frequently observed in serous carcinomas, but not found in adenomas or rarely found in borderline tumors, suggesting that p53 mutations may be directly involved in malignant transformation. TGFbeta-2 mutations are found in 50% of endometrioid carcinoma, but rarely in other type. Loss of DCC mRNA expression is found in 50% of serous carcinomas but less frequently in other type. Loss of DCC expression is rare in borderline tumors and adenomas, suggesting that inactivation of DCC may be directly involved in malignant transformation. Microsatellite instability (MI) is found in 17% of ovarian carcinomas, and is frequently found in endometrioid carcinomas. Although inactivation of p16 by point mutation or deletion is rare, p16 inactivation by loss of expression is relatively common.

Acid Anhydride Hydrolases↗
PubMed2003

Mutations in the STK11 gene characterize minimal deviation adenocarcinoma of the uterine cervix.

Minimal deviation adenocarcinoma (MDA) is a well-differentiated variant of mucinous adenocarcinoma of the uterine cervix and is found relatively infrequently in the general population. However, MDA is strongly associated with Peutz-Jeghers syndrome (PJS), a rare hereditary autosomal disorder characterized by benign hamartomatous polyposis in the gastrointestinal tract and mucocutaneous pigmentation. A serine threonine kinase gene, STK11, has been identified as the tumor suppressor gene responsible for the PJS. In this study we investigated the possible direct role of STK11 in the development of MDA of the uterine cervix. Eleven rare cases of mucinous MDA, not known to be associated with PJS, were screened for the presence of mutations in the STK11 gene by single-strand conformation polymorphism analysis of PCR-amplified DNA fragments. Subsequently our findings were confirmed with cloning and sequencing. As a control, 24 cases of endocervical adenocarcinomas of other histologic subtypes, with no family history of PJS (19 mucinous adenocarcinomas, 4 endometrioid adenocarcinomas, and 1 clear cell adenocarcinoma), 15 cases of squamous cell carcinomas of the uterine cervix, 5 cases of endocervical glands with pyloric gland metaplasia, and 2 deeply situated nabothian cysts were investigated. Somatic mutations of the STK11 gene were confirmed in 6 (55%) of the 11 mucinous MDAs and 1 (5%) of the 19 mucinous adenocarcinomas, but not in the 5 nonmucinous adenocarcinomas, the 15 squamous cell carcinomas, nor the 5 endocervical glands with gastric metaplasia. MDAs with the STK11 mutation had a significantly poorer prognosis than MDAs without the STK11 mutation (p = 0.039). A germline mutation of STK11 was detected in one PJS patient with mucinous adenocarcinoma of the uterine cervix. These results suggest that mutations in the STK11 gene may play an important role in the etiology of MDA of the uterine cervix and may distinguish this rare tumor from other common types of adenocarcinoma of the uterine cervix.

AMP-Activated Protein Kinase Kinases↗
PubMed2003

Monoclonal expansion with integration of high-risk type human papillomaviruses is an initial step for cervical carcinogenesis: association of clonal status and human papillomavirus infection with clinical outcome in cervical intraepithelial neoplasia.

To define the natural history of cervical intraepithelial neoplasia (CIN) as related to clonal status, we evaluated 20 cases of CIN1 and 18 cases of CIN2 that had been clinically followed for 7 to 48 months at Osaka University Hospital. These included 10 cases that progressed, 15 cases that persisted, and 13 cases that regressed. We analyzed the clonal status of each case by analysis of the pattern of X-chromosomal inactivation. Human papillomavirus (HPV) infection was detected by PCR-RFLP analysis. CINs that are monoclonal or infected by high-risk HPVs are more likely to progress or persist than cases that are polyclonal or negative for high-risk HPVs (p = 0.009 for monoclonal vs polyclonal, p = 0.024 for high-risk HPV positive vs negative p = 0.024). Eighteen (90%) of 20 monoclonal, high-risk HPV-associated CINs progressed or persisted, whereas 9 (60%) of 15 polyclonal or high-risk HPV-negative CINs regressed. Therefore, the combination of clonality status and high-risk type HPV infection was significantly correlated with clinical outcome (p = 0.003). The physical status of the HPV genome was evaluated in 17 cases of HPV-16 positive CINs by real-time PCR. Of those, the HPV viral genome was present in both episomal and integrated forms in 14 CINs (84%), and 12 of these cases (86%) were monoclonal in composition. By contrast, all three CINs in which the HPV genome was present in episomal form were polyclonal. In one CIN1 that was polyclonal, HPV-16 was originally present in episomal form but after 24 months, the patient developed a monoclonal CIN3 in which the HPV-16 genome was present in mixed form. These results may imply that HPV viral integration into the host genomic DNA is associated with progression from polyclonal to monoclonal status in CIN. These events may play a fundamental role in the progression from low-grade to higher grade dysplasia of the cervical mucosa.

Clone Cells↗
PubMed2002

Loss of one allele of the p53 gene in the lens epithelial tumor in transgenic mice suppresses apoptosis induced by a topoisomerase I inhibitor (CPT-11).

To examine whether CPT-11 can induce apoptosis in the mouse lens tumor, it was administered to pregnant alphaT3 mice, which developed epithelial tumors in the lens during the perinatal stage. Three different p53 genotypes were generated to analyze the influence of p53 status on tumor cells under chemotherapy. On day 16--17 of gestation, alphaT3 mice received an i.p. injection of CPT-11, and fetal lens tumors were examined 2 days later. Apoptosis in the tumors was observed in both a CPT-11 dose- and p53 gene copy-dependent manner. In addition, it was found that CPT-11 could also induce apoptosis via a p53-independent pathway.

Animals↗
PubMed2002

Quantitative analysis of telomerase hTERT mRNA and telomerase activity in endometrioid adenocarcinoma and in normal endometrium.

OBJECTIVES: In the current study, the quantitative levels of telomerase hTERT mRNA and the functional telomerase repeat amplification protocol (TRAP) assay were correlated with tumor grade in endometrial carcinomas and with the histologic phase of normal endometrium. METHODS: Twenty-six samples of endometroid adenocarcinoma and 20 cases of benign endometrium were obtained from hysterectomy specimens. Total RNA was extracted from each tissue sample and used for quantitative real-time RT-PCR of hTERT mRNA and the levels were standardized to the levels of ribosomal RNA. Quantitative determination of telomerase activity was performed by the polymerase chain-based TRAP assay and the levels of expression were defined by the ratio of radioactivity incorporated into the 6-bp telomerase amplification products versus the radioactivity incorporated into an internal standard (telomerase/ITAS x 100 = 1 RU). Statistical analyses were performed using the Fisher exact test or chi2 test, a Wilcoxon rank sum test, and a linear regression analysis. RESULTS: hTERT mRNA and telomerase activity levels showed a linear association in the study group (P = 0.006, R2 = 0.139). hTERT mRNA levels and telomerase activity levels were significantly higher in endometrial cancer (179 pg/ng rRNA, 44 relative units (RU)) than in normal endometrium (45 pg/ng), (15 RU) (P = 0.009, P = 0.006). In normal endometrium, hTERT mRNA and telomerase activity levels were highest in the proliferative phase (74 pg/ng rRNA, 25 RU) and were relatively low in secretory (13 pg/ng rRNA, 6 RU) and atrophic endometrium (9 pg/ng rRNA, 2 RU). CONCLUSION: These results suggest that the quantitative analysis of hTERT and telomerase activity may have potential roles as diagnostic or prognostic adjuncts for both premenopausal and postmenopausal patients with endometrial cancer.

Adult↗
PubMed2002

Correlation of survivin mRNA detection with histologic diagnosis in normal endometrium and endometrial carcinoma.

BACKGROUND: The objective of this study was to determine if survivin mRNA expression is a marker of endometrioid adenocarcinoma and if survivin mRNA levels correlate with tumor grade and stage. METHODS: Twenty-six samples of endometrioid adenocarcinoma and 18 cases of benign endometrium were obtained at surgery. RNA was extracted from tissues and was used for quantitative real-time RT-PCR, targeting a 91-bp sequence of survivin mRNA and the levels were standardized to the levels of ribosomal RNA. Statistical analysis of the correlation between histologic diagnosis and the corrected survivin mRNA levels was performed by the Fisher Exact test and the Kruskal-Wallis test. RESULTS: Survivin mRNA was detected in all specimens. Survivin mRNA levels were increased in proliferative endometrium (P = 0.0509) and was increased in correlation with ascending grade in endometrioid adenocarcinoma (P = 0.01). CONCLUSION: Survivin mRNA is not a specific marker of endometrial cancer, but may reflect an important mechanism in tumor progression of the endometrial mucosa.

Adenocarcinoma↗
PubMed2002

Clonal analysis and mutations in the PTEN and the K-ras genes in endometrial hyperplasia.

The patterns of X chromosome inactivation and mutations of PTEN and K-ras were evaluated in cases of endometrial hyperplasia to determine the presence of potentially premalignant neoplastic versus polyclonal benign cell populations. Endometrial glandular epithelial cells were collected by laser capture microdissection, and genomic DNAs were extracted. Following treatment with the methylation sensitive restriction endonuclease Hha I, polymerase chain reaction amplification was performed targeting a highly polymorphic short tandem repeat of the human androgen receptor gene (HUMARA). PTEN and K-ras gene mutations were evaluated by analysis of single-strand conformation polymorphism. Two pathologists performed histologic diagnosis of the lesions independently. Monoclonal composition was demonstrated in 13 of 15 (87%) endometrial hyperplasias with atypia and 17 of 31 (55%) complex hyperplasias without atypia. Cytological atypia is significantly associated with the clonal status of the endometrial hyperplasia (13/15 vs 17/31, P = 0.049). In contrast, all 14 normal endometrial tissue samples were polyclonal. PTEN gene mutations were detected in 4 of 13 (30%) monoclonal endometrial hyperplasias with atypia and 2 of 17 (12%) monoclonal endometrial hyperplasias without atypia but were not detected in polyclonal endometrial hyperplasias, with or without atypia. K-ras gene mutations were present in 3 of 13 (23%) monoclonal endometrial hyperplasias with atypia but not in 2 cases of polyclonal endometrial hyperplasia with atypia or in 26 cases of endometrial hyperplasia without atypia. K-ras mutation is thus significantly more frequently found in endometrial hyperplasias with atypia than those without atypia (3/15 vs 0/31, P = 0.030). This study indicates that most cases of endometrial hyperplasia with atypia and a high proportion of cases of endometrial hyperplasias without atypia originate from a single progenitor cell, possibly as a result of genetic alterations, rather than as a result of benign reactive processes.

Cell Transformation, Neoplastic↗