Pharmacogenomics and therapeutic target validation in cerebral vasospasm

One of the most important pharmacogenomic technologies is transcriptome analysis. We used this method to study the change of gene expression profiles in animal models of cerebral vasospasm. We found novel drug target candidates in cerebral vasospasm through pharmacogenomics. By using differential display and quantitative reverse transcriptase-polymerase chain reaction, we found that heme oxygenase-1 (HO-1) mRNA was prominently induced in the basilar artery and modestly in brain tissue in a murine vasospasm model. There was a significant correlation between the degree of vasospasm and HO-1 mRNA levels in the basilar arteries exhibiting vasospasm. Antisense HO-1 oligodeoxynucleotides (ODN) inhibited HO-1 induction in the basilar arteries, but not in the whole brain tissue. This phenomenon was not observed in the nontreatment, sense HO-1 ODN and scrambled ODN treatment arteries. We report, for the first time, the protective effects of HO-1 gene induction by endogenous or clinical compounds in cerebral vasospasm after subarachnoid hemorrhage, a finding that should provide a novel therapeutic target for cerebral vasospasm.

Uterine inversion caused by uterine sarcoma: a case report

Uterine inversion caused by uterine sarcoma is a rare condition with 12 reported cases to date according to a MEDLINE search. We report two cases of this rare condition. A 71- and a 72-year-old woman presented with uterine sarcomas rapidly extruded into the vagina. In both cases, magnetic resonance imaging (MRI) scans showed U-shaped uterine cavities and the pedicles of these tumors were attached to the uterine fundi. Pathological examination confirmed a leiomyosarcoma and a heterologous carcinosarcoma. Uterine inversion can occur when uterine sarcoma rapidly increases in size and extrudes into the vagina. MRI should be performed in the diagnosis of this rare combination.

Loss of heterozygosity on 10q23.3 and mutation of the tumor suppressor gene PTEN in benign endometrial cyst of the ovary: possible sequence progression from benign endometrial cyst to endometrioid carcinoma and clear cell carcinoma of the ovary

Loss of heterozygosity (LOH) at locus 10q23.3 and mutation of the PTEN tumor suppressor gene occur frequently in both endometrial carcinoma and ovarian endometrioid carcinoma. To investigate the potential role of the PTEN gene in the carcinogenesis of ovarian endometrioid carcinoma and its related subtype, clear cell carcinoma, we examined 20 ovarian endometrioid carcinomas, 24 clear cell carcinomas, and 34 solitary endometrial cysts of the ovary for LOH at 10q23.3 and point mutations within the entire coding region of the PTEN gene. LOH was found in 8 of 19 ovarian endometrioid carcinomas (42.1%), 6 of 22 clear cell carcinomas (27.3%), and 13 of 23 solitary endometrial cysts (56.5%). In 5 endometrioid carcinomas synchronous with endometriosis, 3 cases displayed LOH events common to both the carcinoma and the endometriosis, 1 displayed an LOH event in only the carcinoma, and 1 displayed no LOH events in either lesion. In 7 clear cell carcinomas synchronous with endometriosis, 3 displayed LOH events common to both the carcinoma and the endometriosis, 1 displayed an LOH event in only the carcinoma, and 3 displayed no LOH events in either lesion. In no cases were there LOH events in the endometriosis only. Somatic mutations in the PTEN gene were identified in 4 of 20 ovarian endometrioid carcinomas (20.0%), 2 of 24 clear cell carcinomas (8.3%), and 7 of 34 solitary endometrial cysts (20.6%). These results indicate that inactivation of the PTEN tumor suppressor gene is an early event in the development of ovarian endometrioid carcinoma and clear cell carcinoma of the ovary.

Genes encoding nitrilase-like proteins from tobacco

Nitrilase (nitrile aminohydrolase, EC 3.5.5.1) catalyzes the hydrolysis of indole-3-acetonitrile (IAN) to indole-3-acetic acid (IAA). Arabidopsis thaliana genome has four nitrilase genes (NIT1, NIT2, NIT3 and NIT4). Three (NIT1, NIT2 and NIT3) of the four genes have high similarity. We have cloned two NIT4 homologs (TNIT4A and TNIT4B) from tobacco (Nicotiana tabacum). Genomic Southern hybridization, among other experiments, strongly suggests that tobacco has NIT4 homologs but not NIT1 to NIT3 homologs. Introduction of Arabidopsis NIT2 into tobacco conferred IAN-mediated growth inhibition, probably due to hydrolysis of IAN to IAA, while ectopic expression of TNIT4A had little effect on the sensitivity of transgenic plants to IAN. Nitrilase activity of TNIT4 proteins is discussed.

Metachronous carcinoma of the vulva and fallopian tube

BACKGROUND

Metachronous carcinoma of the vulva and fallopian tube is an unusual co-occurrence of gynecological malignancies. A report of such a case that developed and recurred over a 7-year period is presented.

CASE

A 53-year-old G3P3 female presented with a verrucous carcinoma of the vulva and a serous papillary adenocarcinoma of the left fallopian tube metachronously. To investigate a possible association between the co-occurrence of the rare neoplasms and factors associated with multiple gynecological malignancies, we analyzed the status of human papillomavirus infection and DNA mismatch repair deficiency as indicated by microsatellite instability. All samples analyzed were negative for these factors.

CONCLUSION

The present results support the possibility that metachronous carcinomas of the vulva and fallopian tube involve unknown etiological factors or arise independently.

Site-specific integration of adeno-associated virus-based plasmid vectors in lipofected HeLa cells

Adeno-associated virus (AAV) integrates specifically into a site (AAVS1) on human chromosome 19q13.3-qter. Similarly, there is accumulating evidence that this site-specific integration occurs by transfection of AAV-based plasmid vectors. In order to further define the process of plasmid integration events, we constructed some AAV plasmids, introduced them into HeLa cells by lipofection, and isolated chromosomal integrants. One of such plasmids, pTH-5, contained the rep and neomycin-resistant (neo(r)) genes flanked by the 5'- and 3'-inverted terminal repeats of AAV and the hygromycin-resistant (hyg(r)) gene located in the plasmid backbone. Southern blot analysis revealed that among 36 G418-resistant (G418(r)) clones isolated, 22 (61%) showed site-specific integration into AAVS1. Further structural and functional analyses on the expression of the hyg(r) gene in the site-specific clones and the LacZ gene in clones generated with plasmid pTH-2 indicated that, together with the AAV sequence, the plasmid backbone was integrated into the AAVS1 site and thus the neo(r) and hyg(r) genes remained linked at high frequencies in the targeted integrants compared with random integrants. Sequence analysis of integration junctions between pTH-5 and AAVS1 revealed that the junctions occurred in the p5 promoter region of the plasmid while mainly in the partial cDNA coding region of the AAVS1 site. We also found that plasmid pTH-1 linearized in the backbone before lipofection gave a significantly lower frequency of site-specific integration (26%) than the circular form (60%). This finding may support the involvement of the double-stranded, circular form of infected AAV in the integration process. Our results may help to understand the process and mechanism of site-specific integration of lipofected AAV plasmid vectors.

[Phase I study of a combination chemotherapy of nedaplatin and cisplatin]

A new platinum complex, nedaplatin, has been reported to be effective for both ovarian and cervical cancers. We designated a phase I dose-escalation study of a combination chemotherapy of nedaplatin and cisplatin to investigate the dose-limiting toxicity (DLT) and the maximum tolerated dose (MTD). Six patients, including two with advanced cervical cancer, three with ovarian clear cell adenocarcinoma and one with endometrial clear cell adenocarcinoma, were enrolled in this study. The doses of the two agents were escalated alternatively, i.e., a tandem method, from 40 to 80 mg/m2 by 20 mg/m2. Nedaplatin and cisplatin were administrated by intravenous drip infusion and repeated after an interval of at least 4 weeks, as a rule. The major toxicity observed was hematotoxicity. One of the 6 patients dropped out of this study because of severe hematotoxicity after 80 mg/m2 of nedaplatin and 60 mg/m2 of cisplatin were administered. With a dose of 80 mg/m2 nedaplatin and 80 mg/m2 cisplatin, severe neutropenia was found in all 6 patients, and thrombocytopenia and anemia were found in 1 patient, respectively. A slight hearing loss was detected by audiometry in 5 patients, but no one was inconvenienced in daily life. Mild nausea and vomiting were also observed in all 6 patients. In conclusion, the DLT of this combination therapy was hematotoxicity and the MTD was 80 mg/m2 for nedaplatin and 60 mg/m2 for cisplatin, respectively. Thus, 60 mg/m2 of nedaplatin and 60 mg/m2 of cisplatin may be recommended for combined administration.

Structural analysis of the TNIT4 genes encoding nitrilase-like protein from tobacco

Nitrilase (nitrile aminohydrolase, EC 3.5.5.1) catalyzes the hydrolysis of indole-3-acetonitrile (IAN) to indole-3-acetic acid (IAA). The Arabidopsis thaliana genome has four nitrilase genes (NIT1 to NIT4), while tobacco (Nicotiana tabacum) has only NIT4 homologs (TNIT4A and TNIT4B) and no NIT1 to NIT3 homologs. We have cloned the promoter region of TNIT4B and determined the transcriptional start sites which are the same sites in both TNIT4A and TNIT4B. The TNIT4 genes are expressed in various organs at low levels. The positions of the exon-intron splicing junctions in Arabidopsis NIT1 to NIT3 are completely conserved in TNIT4A.

[Heme oxgenase-1 gene induction and the mechanism in the rat vasospasm model]

Using fluorescent differential display and quantitative reverse-PCR, we found in the rat vasospasm model that heme oxygenase-1 messenger RNA was induced in basilar artery. Intracistemal injection of antisense OH-1 oligodeoxynucleotide significantly reduced HO-1 mRNA and HO-1 protein levels and enhanced angiographic vasospasm. Thus, we demonstrate that HO-1 induction may play a important role in the resolution of delayed vasospasm after subarachnoid hemorrhage.

The adenovirus E1A domains required for induction of DNA rereplication in G2/M arrested cells coincide with those required for apoptosis

Induction of apoptosis by adenovirus E1A in rodent cells is stimulated by wild type (wt) p53 but completely suppressed by mutated p53. The suppression is overcome by coexpression with Id proteins (Ids). The cells expressing E1A and Ids undergo apoptosis after accumulation in S phase, suggesting that S phase events are perturbed by E1A and Ids. The E1A domains required for induction of apoptosis, analysed by transfection with expression vectors for E1A, Ids and their mutants, followed by flow cytometry, reside in N-terminal (positions 17 - 38), CR1 and CR2 regions. Interaction of E1A with Ids requires the N-terminal and CR1 regions. The cyclin D1 promoter activity in S phase was reduced severely by E1A and this reduction is caused through CR1 and CR2 regions required for interaction with pRB. Analysis of DNA synthesis in G2/M arrested cells indicated that E1A is capable of inducing >4 N cells and this E1A-mediated DNA rereplication is enhanced by coexpression with Id-1H. The E1A domains required for induction of DNA rereplication coincide with those required for apoptosis.

Heme oxygenase-1 gene induction as an intrinsic regulation against delayed cerebral vasospasm in rats

Delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) causes cerebral ischemia and infarction. To date, the pathogenesis and gene expression associated with vasospasm remain poorly understood. The present study used fluorescent differential display to identify differentially expressed genes in a rat model of SAH. By using quantitative RT-PCR, we found that heme oxygenase-1 (HO-1) mRNA was prominently induced in the basilar artery and modestly in brain tissue in a rat vasospasm model. A significant correlation was observed between the degree of vasospasm and HO-1 mRNA levels in the basilar arteries exhibiting vasospasm. Intracisternal injection of antisense HO-1 oligodeoxynucleotide (ODN) significantly delayed the clearance of oxyhemoglobin and deoxyhemoglobin from the subarachnoid space and aggravated angiographic vasospasm. Antisense HO-1 ODN inhibited HO-1 induction in the basilar arteries but not in the whole brain tissue. This phenomenon was not observed in the nontreated, sense HO-1 ODN-treated, or scrambled ODN-treated arteries. We report the protective effects of HO-1 gene induction in cerebral vasospasm after SAH, a finding that should provide a novel therapeutic approach for cerebral vasospasm.

Identification of a novel GC-rich 113-nucleotide region to complete the circular, single-stranded DNA genome of TT virus, the first human circovirus

The sequence data (H. Okamoto et al., Hepatol. Res. 10:1-16, 1998) of a newly discovered single-stranded DNA virus, TT virus (TTV), showed that it did not have the terminal structure typical of a parvovirus. Elucidation of the complete genome structure was necessary to understand the nature of TTV. We obtained a 1.0-kb amplified product from serum samples of four TTV carriers by an inverted, nested long PCR targeted for nucleotides (nt) 3025 to 3739 and 1 to 216 of TTV. The sequence of a clone obtained from serum sample TA278 was compared with those registered in GenBank. The complete circular TTV genome contained a novel sequence of 113 nt (nt 3740 to 3852 [=0]) in between the known 3'- and 5'-end arms, forming a 117-nt GC-rich stretch (GC content, 90.6% at nt 3736 to 3852). We found a 36-nt stretch (nt 3816 to 3851) with an 80.6% similarity to chicken anemia virus (CAV) (nt 2237 to 2272 of M55918), a vertebrate circovirus. A putative SP-1 site was located at nt 3834 to 3839, followed by a TATA box at nt 85 to 90, the first initiation codon of a putative VP2 at nt 107 to 109, the termination codon of a putative VP1 at nt 2899 to 2901, and a poly(A) signal at nt 3073 to 3078. The arrangement was similar to that of CAV. Furthermore, several AP-2 and ATF/CREB binding sites and an NF-kappaB site were arranged around the GC-rich region in both TTV and CAV. The data suggested that TTV is circular and similar to CAV in its genomic organization, implying that TTV is the first human circovirus.

Differential diagnosis of gynaecological "stained glass" tumours on MRI

Although multilocular cystic gynaecological masses in which the loculi show variable signal intensity on both T1 and T2 weighted images have been considered to be mucinous cystadenoma or adenocarcinoma, other gynaecological tumours can demonstrate this "stained glass" appearance. These include mature cystic teratoma, fibrothecoma, endometrioma, Brenner's tumour of the ovary and degenerated leiomyoma of the uterus, all of which may mimic mucinous tumours of the ovaries.

A novel adenovirus E1B19K-binding protein B5 inhibits apoptosis induced by Nip3 by forming a heterodimer through the C-terminal hydrophobic region

The adenovirus E1B19K protein inhibits apoptosis induced by E1A and other divergent signals. The cellular proteins that interact with E1B19K have been analyzed by isolating cDNA clones by the yeast two hybrid system. One of these clones encodes B5 which consists of 219 amino acid residues and contains the putative BH3 and transmembrane regions. B5 binds strongly to Nip3 and itself, weakly to E1B19K, but not to Bcl-2 and localizes in nuclear envelope, endoplasmic reticulum and mitochondria. B5 has sequence homology with Nip3 in the middle and C-terminal regions, but not in the N-terminal region. Unlike other E1B19K binding BH3 proteins so far characterized, B5 does not induce apoptosis, but inhibits apoptosis induced by Nip3. However the deletion mutant B5Delta1-31 lacking the N-terminus does induce apoptosis, although weaker than does Nip3, suggesting that the N-terminal region is masking the apoptosis-inducing capacity of B5.

Effects of wild-type and mutated p53 and Id proteins on the induction of apoptosis by adenovirus E1A, c-Myc, Bax, and Nip3 in p53 null mouse cerebellum cells

The sensitivities of apoptosis induced by E1A, c-Myc, Bax, and Nip3 to wild-type (wt) and mutated p53 and Id proteins were analyzed by transient transfection followed by flow cytometry with p53 null mouse cerebellum cell lines W7 and M13 that express wt and mutated p53 in response to dexamethasone, respectively. Apoptosis induced by c-Myc was stimulated weakly by wt p53, strongly by Ids, but suppressed completely by mutated p53 irrespective of coexpression with Ids, while apoptosis induced by E1A was suppressed by mutated p53 but stimulated when coexpressed with Ids. Apoptosis induced by Bax was little affected by wt and mutated p53, but inhibited by Ids, while apoptosis induced by Nip3 was inhibited by both wt and mutated p53 and inhibition was stimulated by Ids. Caspase-1 was activated only by Bax significantly when coexpressed with mutated p53 but not with wt p53. These results indicate that the apoptotic processes elicited by these inducers are different and differently affected by wt and mutated p53 and by Ids.

Molecular cloning and characterization of human PDE8B, a novel thyroid-specific isozyme of 3',5'-cyclic nucleotide phosphodiesterase

We have identified a novel human isozyme of 3',5'-cyclic nucleotide phosphodiesterase (PDE), which we designated PDE8B. cDNA of 2844 bp encoding the C-terminal 659 amino acids of PDE8B was cloned following the identification of an expressed sequence tag (EST) obtained through a search of the EST database. The predicted protein sequences of PDE8B showed highest homology (65% identity, 83% similarity) to that of PDE8A. Northern blot analysis indicated that the mRNA encoding PDE8B is expressed specifically and abundantly in thyroid gland as a approximately 4.2 kb mRNA, in contrast to the wide expression of PDE8A mRNA in various tissues. The carboxyl-terminal 584 amino acids of PDE8B were expressed in E.coli as a fusion protein. The recombinant PDE8B exhibited cAMP PDE activity which was not inhibited by various PDE inhibitors including vinpocetine, milrinone, rolipram, and IBMX with the exception of dipyridamole which caused 50% inhibition at a concentration of 40 microM. cAMP hydrolytic activity was unaffected by cGMP and no cGMP PDE hydrolysis were detectable at concentrations up to 100 microM. These findings suggest that PDE8B is a new member of the PDE8 family.

Stabilization of p53 by adenovirus E1A occurs through its amino-terminal region by modification of the ubiquitin-proteasome pathway

The human epidermoid carcinoma-derived cell line MA1, established by introduction of the adenovirus E1A 12 S cDNA linked to the hormone-inducible promoter, elicits apoptosis after induction of E1A12 S in response to dexamethasone. E1A expression caused accumulation of wild type p53 more than 10-fold within 24 h after dexamethasone treatment. The cell lines that express E1A mutants containing a deletion either in the amino terminus or the conserved region 1 were unable to accumulate p53. p53 accumulated was degraded efficiently in vitro in the S10-0 extract (S10-0) prepared from MA1 cells in an ATP and ubiquitin-dependent manner, but not in S10-24 prepared after treatment with dexamethasone for 24 h. The p53 polyubiquitination activity in S100-0 was calcium-dependent and reduced greatly in S100-24. Ubiquitin affinity chromatography revealed that p53 ubiquitination activity in eluates thought to contain ubiquitin-conjugating enzymes decreased greatly in S100-24 as compared with S100-0. The accumulation of p53 was accompanied by the increase in the level of Mdm2, which has been shown to degrade p53 through binding to it. The high p53 level, however, was maintained until the late stage of the apoptotic process. These results indicate that the stabilization of p53 by E1A occurs through modification of a ubiquitin-specific enzyme(s) in the ubiquitin-proteasome pathway.

A novel human glassy-cell carcinoma cell line producing IL-6 and IL-8 from uterine cervix

A novel human cell line, TOM-2, was established from a rare uterine cervical cancer, glassy cell carcinoma (GCC). TOM-2 is the second established GCC cell line so far reported. The cells were intermediately or poorly differentiated with dysplastic nuclei and polygonal shape and secreted two tumor markers and cytokines, i.e., CA-125 and SCC, interleukin (1L)-1alpha, -6, and -8, and TNF-alpha. Growth of TOM-2 was so strongly dependent on population density that it was not possible to determine the plating efficiency. In mass culture, the following characteristics were observed: doubling time, 83 h; mode of chromosome number, 79; human papillomavirus type 18 DNA, detectable; tumorigenicity, easily transplantable into subcutis of nude mice; chemosensitivity in vitro, considerably sensitive to Cisplatin and 5-FU but not to 9 other antineoplastic agents. This novel cell line will be useful for developing new therapeutic strategies for the rare cancer, GCC.

Characterization of human amniotic epithelial cells transformed with origin-defective SV40 T-antigen gene

This paper describes characteristics of human amniotic epithelial cells (AEC) transfected with a gene of origin-defective simian virus (SV) 40 large T-antigen (pMTIOD). Normal AEC before transfection with pMTIOD exhibited only low proliferative potential under our culture conditions. On the other hand, AEC cells transfected with pMTIOD exhibited greater proliferative potentials. Flow cytometry and immunohistochemistry analyses showed that both the primary and the transfected AEC did not express appreciable levels of class II antigens. However, the expression of class I antigen of the transfected AEC cells was slightly increased. The cells obtained in this experiment have the ability to induce tumors in severely combined immunodeficiency mice. This finding suggests that established AEC line can be used as a tool to investigate possible expression of the desired gene in human AEC and the gene products, however, was not suitable as a gene carrier to the recipient. Further experiments will be required to establish AEC as a transgene carrier for somatic cell gene therapy.

Pregnancy increases ET-1-induced contraction and changes receptor subtypes in uterine smooth muscle in humans

The purpose of the present study was to investigate whether pregnancy affects endothelin (ET)-1-induced contraction, the density ofET receptors, and the ratio of receptor subtypes (ET(A) and ET(B)) in uterine smooth muscle in humans. We also investigated which ET receptor subtypes mediate ET-1-induced contraction in the human uterus. In uterine membrane preparations, (125)I-labeled ET-1 ((125)I-ET-1) binding sites (Bmax) in pregnant women did not differ from those in age-matched nonpregnant women (596.2 +/- 107.1 vs. 512.1 +/- 167.7 fmol/mg protein). The dissociation constant (Kd) in pregnant women did not differ from that in nonpregnant women. Competitive displacement experiments with (125)I-ET-1 binding to the membranes using BQ-123 (ET(A) receptor antagonist) showed that the percentage of ET(A) receptors in uterine muscle was significantly higher in pregnant women than in nonpregnant women (P < 0.01). The calculated ratios of ET(A) to ET(B) receptors in pregnant and nonpregnant uteri were 92:8 and 68:32, respectively. Combination treatment with BQ-788 (ET(B) receptor antagonist) completely inhibited the BQ-123-resistant component of (125)I-ET-1 specific binding. ET-1 caused dose-dependent contractions in isolated human uteri from both pregnant and nonpregnant women. The maximum response was markedly greater in pregnant women than in nonpregnant women, whereas pD2 (-log[EC50]) values did not differ between pregnant and nonpregnant uteri. In pregnant human uterus, BQ-123 (10(-6) M) significantly shifted the dose-dependent curve of ET-1 response to the right, whereas BQ-3020 (ET(B) receptor agonist) did not cause contraction. These results suggested that ET-1-induced contraction of the human uterus is mediated through only ET(A) receptors and that ET-1-induced uterine contraction in humans is markedly increased during pregnancy. In addition, the present study suggests that, although (125)I-ET-1 Bmax are not altered during pregnancy, the proportion of ET(A) receptors is increased and that of ET(B) receptors is decreased in the pregnant human uterus.

Inactivation of p16/CDKN2 and p15/MTS2 genes in different histological types and clinical stages of primary ovarian tumors

To define the involvement of p16/CDKN2 and p15/MTS2 inactivation in ovarian tumorigenesis and the association of these inactivation events with histological types and clinical stages of ovarian tumors, we analyzed homozygous deletion and somatic mutation of p16/CDKN2 and p15/MTS2 genes, as well as hypermethylation of the 5'-CpG island of the p16/CDKN2 gene, in 49 primary ovarian tumors and 6 ovarian carcinoma cell lines. We found homozygous deletions of p16/CDKN2 and p15/MTS2 in 6 (12%) and 5 (10%) primary tumors, respectively. Somatic mutation of p16/CDKN2 was found in only 1 primary tumor, but mutation of p15/MTS2 was not detected in any sample. None of the 28 primary tumors or 6 cell lines was hypermethylated at the 5'-CpG island of p16/CDKN2. The incidence of inactivation of p16/CDKN2 in primary tumors was significantly higher in the advanced stages (7 of 29) than in the early stages (0 of 14). Seven of 9 alterations in p16/CDKN2 and p15/MTS2 were observed in serous (3 of 12), endometrioid (3 of 9) and clear-cell (1 of 4) carcinomas. However, only normal sequences of these genes were detected in mucinous carcinomas. Loss of heterozygosity (LOH) at the IFNA locus was detected in 1 of 19 (5%) tumors, but no change at the D9S171 locus was observed in 17 tumors. These results suggest that: (i) homozygous deletion is the main mechanism of inactivation of p16/CDKN2 and p15/MTS2 in ovarian tumorigenesis; (ii) inactivation of p16/CDKN2 and p15/MTS2 may be the histological type-specific events involved in ovarian tumorigenesis; and (iii) inactivation of p16/CDKN2 is potentially involved in the progression of ovarian tumors in advanced stages.

Mutation analysis of gonadotropin receptor and G protein genes in various types of human ovarian tumors

The heterotrimeric guanine-nucleotide-binding proteins (G proteins) and G protein-coupled hormone receptors including gonadotropin receptors have been suggested to play a role in ovarian tumorigenesis. However, no functional significance of gonadotropin receptors and G proteins in this process has been demonstrated. To investigate this issue, we examined point mutations in these genes in various types of ovarian tumors by polymerase chain reaction-single strand conformation polymorphism analysis and direct sequencing. Among 37 tumors (20 epitherial, 8 sex cord-stromal, and 9 germ cell tumors) and 5 carcinoma cell lines examined, no mutational sequence of G protein-interaction domains of luteinizing hormone receptor and follicle-stimulating hormone receptor, or "hot spots" of the alpha subunit of adenylyl cyclase-stimulating G protein and -inhibitory G protein was observed. Although this analysis was performed on only a limited number of tumors and cell lines, and on limited gene loci, the results suggest that mutational activation in gonadotropin receptors and G proteins is not crucial for ovarian tumorigenesis.

[Incidence of synchronous or metachronous multiple primary cancers and aggregation of cancers in families of patients with endometrial cancer]

We evaluated the incidence of synchronous or metachronous multiple primary cancer, hereditary or familial cancer, and the familial aggregation of cancer in 142 patients who were treated for endometrial cancer at Tsukuba University Hospital in the period 1977 to 1995. Synchronous multiple primary cancers were identified in 6 of the 142 patients (4.2%). Eleven patients (7.7%) had a history of extraendometrial cancer. Patients with endometrial cancer had a significantly high incidence of a history of breast cancer. Endometrial cancer was diagnosed in two patients who were screened before menopause. Four patients with endometrial cancer (2.8%) subsequently developed extraendometrial forms of cancer. One patient (0.7%) was considered to have a hereditary form of cancer, and 5 patients (3.5%) had familial forms of cancer. A total of 86 cases of cancer were found among 53 kindred (37.3%). More detailed studies are needed to elucidate the aggregation of cancers in the families of patients with endometrial cancer in Japan. Patients with a history of breast cancer should be screened for the presence of endometrial cancer.