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PubMed2006

Opa interacting protein 5 (OIP5) is a novel cancer-testis specific gene in gastric cancer.

BACKGROUND: Identification of novel cancer-specific antigens is important for the advancement of immunotherapy. Our aim was to identify cancer-specific genes in gastric cancer. METHODS: Using cDNA microarray analysis, we detected genes overexpressed specifically in gastric cancer cells. The expression levels of selected genes, including OIP5, was confirmed by real time RT-PCR analysis in tumor/normal paired bulk samples of 58 clinical cases. The expression levels of selected genes in normal tissues were also determined with a human total RNA master panel. We also compared the expression status of OIP5 with that of the other known cancer-testis specific genes. RESULTS: Twenty-two genes were determined to be upregulated in gastric cancer cells. Among these, three genes (CDC6, Exo1, and OIP5) were selected and confirmed to be upregulated in the tumor tissue compared to normal tissue. A human total RNA master panel demonstrated that OIP5, but not Exo1 or CDC6, showed high specificity in testis. Thus OIP5 may be considered a cancer-testis specific gene. In 58 clinical cases of gastric cancer examined, we found OIP5 gene expression in 27 cases (47%). Thirteen of these 27 cases showed no expression of the known cancer specific genes such as MAGE-1, MAGE-3 or NY-ESO-1. CONCLUSIONS: Using a combination of LMD and microarray, we identified OIP5 as a cancer-testis specific gene. Further expression analysis in a set of clinical cases revealed that OIP5 may be a novel immunotherapy target for patients with gastric cancer.

Adenocarcinoma↗
PubMed1998

Characterization of cytoplasmic dynein light-intermediate chain isoforms in rat testis.

We obtained three kinds of novel cytoplasmic dynein light-intermediate chain (LIC) isoforms from rat testis and brain by reverse transcription polymerase chain reaction (RT-PCR). The primers for RT-PCR were designed according to LIC-2 (LIC 53/55) (15). In one novel isoform, the 42 bp specific sequence named TDL was inserted between 1,106 and 1,107 nucleotides (nts) of LIC-2, whereas the 57 bp sequence corresponding to LIC-2 1,339-1,395 nts (BDL) was absent. The TDL and BDL regions were specifically digested with restriction enzymatic treatment and followed by subcloning of non-digested cDNA band in testis and brain, producing an isoform without TDL and BDL regions. BDL specific RT-PCR of testis cDNA followed by sequencing produced an isoform with two specific regions. By Northern blot hybridization using TDL and BDL specific antisense oligo DNA probe, 4.4, 3.5, and 2.0 kb of signals were detected. With both TDL and BDL probes, the 2.0 kb signal was intensely detected in testis, while the 4.4 kb was defected in brain. This indicates that TDL and BDL are derived from the same size of mRNAs. In situ hybridization method using these probes showed that all seminiferous epithelial cells, especially late pachytene spermatocytes, were positive, indicating that LIC 53/55 isoforms were coexpressed in these cells. These findings indicate that LIC 53/55 isoforms provide a variety of dynein subunits, and thus may regulate the dynein-dependent intracellular transport system.

Alternative Splicing↗
PubMed1998

Structural analysis of milk and testis beta-1,4-galactosyltransferase gene products.

There seems to exist a relatively low similarity between the amino acid sequences of the testis and milk beta-1,4-galactosyltransferase gene products. However, the predicted higher structures of testis and milk beta-1,4-galactosyltransferase proteins revealed a highly significant similarity in the regions required for enzymatic activities. Testis beta-1,4-galactosyltransferase protein contained a WD repeat similar to the motif of the G protein beta subunit type I and a Zn-finger motif at the N- and C-terminal portions of the protein, respectively. Phylogenetic analysis of glycosyltransferase proteins revealed that the ancestral gene of testis and milk beta-1,4-galactosyltransferases and alpha-1,3-galactosyltransferase evolved into three different destinations at about the same time on an evolutionary scale.

Amino Acid Sequence↗
PubMed1991

High levels of cholesteryl esters, progesterone and estradiol in the testis of aging male Fischer 344 rats: feminizing Leydig cell tumors.

The levels and fatty acid composition of cholesteryl esters (CEs), and the levels of steroid hormones in the testis of aging Fischer 344 (F344) rats were studied in comparison with those of 6-month-old rats without Leydig cell tumors (controls). The total lipid content in the testis increased as Leydig cell tumors developed: in 23-month-old rats, the content increased to five times higher than that of the controls. The CE level reached about 300 times higher than that of the controls and comprised 57.5% of the total lipid of the testis. The fatty acid composition of the CEs in the tumor compared to the normal tissue from the controls was characterized by a marked increase in 22:4 (n-6) and a decrease in 22:5 (n-6), a characteristic acid in rat testis lipids. Testicular progesterone levels considerably increased with the development of tumors (23-month-old rats, 2870 ng/wet wt; controls, 7 ng/g wet wt). Also, levels of estradiol showed striking increments (23-month-old rats, 2205 pg/g wet wt; controls, 153 pg/g wet wt). On the other hand, testosterone levels decreased (23-month-old rats, 13 ng/g wet wt; controls, 50 ng/g wet wt). These results suggest that Leydig cell tumors in aging F344 rats resemble the ovary tissue of rats in the levels and fatty acid composition of the CEs, and in the levels of steroid hormones. This is supported by the observation that the two kinds of cells found in the tumor tissue resemble cells of the corpus luteum and granulosa cells of the follicles, respectively, in the ovary of rats. In conclusion, the study shows that Leydig cell tumors in aging male F344 rats have a tendency towards feminization.

Aging↗
PubMed1999

Effect of neonatal exposure to estrogenic compounds on development of the excurrent ducts of the rat testis through puberty to adulthood.

Neonatal exposure to diethylstilbestrol (DES) can alter the structure of the testicular excurrent ducts in rats. We characterized these changes according to dose and time posttreatment and established whether potent estrogens (ethinyl estradiol), environmental estrogens (genistein, octylphenol, bisphenol A, parabens), and tamoxifen induce such changes. Rats were administered these compounds neonatally and assessed at several time points during (day 10, or day 18 for some treatments) and after (days 18, 25, 35, and 75) the treatment period to detect any changes in testis weight, distension of the rete testis and efferent ducts, epithelial cell height in the efferent ducts, and immunoexpression of the water channel aquaporin-1 (AQP-1). Treatment with DES (10, 1, or 0.1 microg/injection; equivalent to 0.37, 0.037, or 0.0037 mg/kg/day, respectively) induced dose-dependent changes in testis weight and all parameters. These effects were most pronounced at days 18 and 25 and appeared to lessen with time, although some persisted into adulthood. Neonatal treatment with ethinyl estradiol (10 microg/injection; equivalent to 0.37 mg/kg/day) caused changes broadly similar to those induced by 10 mg DES. Administration of tamoxifen (2 mg/kg/day) caused changes at 18 days that were similar to those induced by 1 microg DES. Treatment with genistein (4 mg/kg/day), octylphenol (2 mg/injection; equivalent to 150 mg/kg/day), or bisphenol A (0.5 mg/injection; equivalent to 37 mg/kg/day) caused minor but significant (p<0.05) decreases in epithelial cell height of the efferent ducts at days 18 and/or 25. In animals that were followed through to 35 days and/or adulthood, these changes were no longer obvious; other parameters were either unaffected or were affected only marginally and transiently. Administration of parabens (2 mg/kg/day) had no detectable effect on any parameter at day 18. To establish whether these effects of estrogens were direct or indirect (i.e., resulting from reduced follicle-stimulating hormone/luteinizing hormone secretion), the above end points were assessed in animals in which gonadotropin secretion was suppressed neonatally by administration of a gonadotropin-releasing hormone antagonist. This treatment permanently reduced testis weight, but did not affect any of the other end points, apart from a minor transient reduction in efferent duct epithelial cell height at 18 days. This study suggests that structural and functional (expression of AQP-1) development of the excurrent ducts is susceptible to impairment by neonatal estrogen exposure, probably as a consequence of direct effects. The magnitude and duration of adverse changes induced by treatment with a range of estrogenic compounds was broadly comparable to their estrogenic potencies reported from in vitro assays.

Animals↗
PubMed2001

Effects of short photoperiod on the expression of smad2 and smad3 mRNA in Syrian hamster testis.

The testicular localization and expression of Smad2 and Smad3 mRNA involved in the intracellular signal transduction of activin, inhibin and transforming growth factor-beta (TGF-beta) were examined under the influence of long and short photoperiod in Syrian hamsters (Mesocricetus auratus). In situ hybridization detected both Smad2 and Smad3 mRNA in spermatogonia and premeiotic spermatocytes in the active testis exposed to a long photoperiod, as well as in the regressed testis exposed to a short photoperiod. Northern blots showed that Smad2 mRNA was expressed at all stages over long and short photoperiods, whereas Smad3 mRNA was expressed at high levels in the photoperiod-induced regressed testis. The photoperiodic condition would change the balance between Smad2 and Smad3 transcripts in the testis. Thus, intracellular Smad2 and Smad3 might participate in transducing signals from activin, inhibin and TGF-beta in spermatogenetic cells.

Animals↗
PubMed2002

Gonadosomatic index and testis morphology of common carp (Cyprinus carpio) in rivers contaminated with estrogenic chemicals.

To study the effect of estrogenic chemicals on fish, the gonadosomatic index (GSI = [testis weight/body weight] x 100) and testis histology of mature common carp (Cyprinus carpio) from 2 contaminated sites (Ishizu and Wada rivers, Osaka) and a control site were examined between June 1998 and March 2001. The concentration of nonylphenol, bisphenol A and 17beta-estradiol in the Ishizu river was 3-4 times higher than in the Wada river. In the pre-breeding and breeding seasons, there were no significant differences in body weight among carp from the 3 sites, the body weight of Ishizu river carp being significantly lower (p<0.05) than that of Wada river fish only in the post-breeding season. The GSI and testis weight in fish from the Ishizu river were significantly lower (p<0.05) than in control fish during all phases of gonadal cycle and lower than in Wada river fish in the pre-breeding and post-breeding season. No histological abnormalities were found in the testes of the males examined. Histological observation of the testes revealed a delay in the onset of spermatogenesis in fish from the Ishizu river compared with those from the other sites. These results clearly imply that the estrogenic chemicals in the Ishizu river adversely affect the testis development of the fish.

Animals↗
PubMed2004

Expression of constitutive endothelial, neuronal and inducible nitric oxide synthase in the testis and epididymis of horse.

The expression of three isoforms of nitric oxide synthase (NOS) were examined in the testis and epididymis of a thoroughbred horse. Immunohistochemical studies demonstrated the presence of eNOS immunostaining in some germ cells in the seminiferous tubules and in vascular endothelial cells in the interstitial tissues. Interstitial cells, most likely Leydig cells, were also intensely immunopositive for eNOS. The pattern of immunostaining for nNOS was similar to that for eNOS in the testis. Weak expression of iNOS was detected in the seminiferous tubules of the testis, but intense expression was found in interstitial cells. Inducible NOS was also strongly detected in stereocilia, sperm, epithelium and connective tissue of the epididymis of normal horses. These findings suggest that three isoforms of NOS are expressed in the testis and epididymis of horse and that they play important roles in the biology of interstitial cells that produce testosterone, as well as in spermatogenesis in the seminiferous tubules.

Animals↗
PubMed2001

Cytochrome P450 aromatase in testis and epididymis of male rhesus monkeys.

To understand the role of estrogen in testicular and epididymal function of rhesus monkeys, we measured steroids in the spermatic and peripheral venus circulation and aromatase activity and its mRNA in testis and epididymis. Testosterone, estradiol-17beta, and estrone, but not androstenedione, were elevated in the spermatic vein serum compared to the peripheral circulation. Aromatase activity in testis and in caput epididymis (259+/-16 [SEM] vs 274+/-47 fmol of 3H2O/mg of protein/h [n = 10], respectively) was significantly higher (p < 0.01) than in corpus and cauda (124+/-28 and 113+/-33 fmol of 3H2O/mg of protein/h [n = 10], respectively). In the ribonuclease protection assay, two P450arom mRNA transcripts were identified in testis and epididymis. One corresponded with the aromatase full-length transcript and the other was a truncated isoform. The latter was significantly more abundant than the former (p < 0.01). Our results demonstrate that the monkey testis and, to a lesser extent, the epididymis can aromatize androgens. However, in the epididymis, like in some areas of the brain, there was a discrepancy between the aromatase activity and the mRNA. The fact that P450arom mRNA and aromatase activity do not correlate in the epididymis may indicate that aromatase activity is not strictly regulated at the level of RNA expression and that other mechanisms for this regulation should be considered.

Animals↗
PubMed2004

L-prostaglandin D synthase expression and regulation in mouse testis and epididymis during sexual maturation and testosterone treatment after castration.

Lipocalin-type prostaglandin D synthase (L-PGDS) is highly expressed in the adult testis and epididymis of many mammals. The present study was to investigate L-PGDS expression in mouse testis and epididymis during sexual maturation, and the effects of testosterone replacement on L-PGDS expression in epididymis by in situ hybridization and immunohistochemistry. Both L-PGDS mRNA and protein were highly expressed in the interstitial tissue of adult testis. L-PGDS mRNA was first detected on d 30 after birth and exhibited an abundant signal in adult caput and cauda epididymis. L-PGDS immunostaining was first observed on d 30 after birth. There was a strong level of L-PGDS immunostaining in adult epididymis. Castrated male mice were treated with either vehicle or testosterone propionate following 3 d postcastration. L-PGDS expression steadily declined in a time-dependent fashion in control groups. No L-PGDS mRNA expression or immunostaining was detected in the controls for 12 d. When the castrated mice were treated with testosterone propionate for 5 or 12 d, L-PGDS expression was significantly increased in the whole epididymis. These data suggest that L-PGDS expression in mouse epididymis gradually declined in parallel to the declining concentration of endogenous androgen after castration and increased with the treatment of exogenous testosterone, indicating that L-PGDS expression in mouse epididymis was modulated by androgen levels. However, differential expression in different areas of the epididymis may also be influenced by factors derived from the testis.

Animals↗
PubMed1999

Sertoli cell expression of galectin-1 and -3 and accessible binding sites in normal human testis and Sertoli cell only-syndrome.

Galectins are vertebrate lectins interacting with beta-galactosides and derivates thereof such as blood group A, B and H determinants. The expression of gelectin-1 and -3 and galectin-specific binding sites by human Sertoli cells was analyzed in normal human testis and Sertoli cell only-syndrome (SCOS). Staining intensity was scored semiquantitatively on a 4-grade scale. Sertoli cells in normal testes displayed a moderate cytoplasmic and weak nuclear staining for galectin-1-specific binding sites. Galectin-3-specific binding sites were expressed in Sertoli cells less intensely than accessible ligands for galectin-1 (mean score 2.25 for galectin-1 and 1.50 for galectin-3). Germ cells were only weakly reactive. Tubular walls were negative for both classes of galectin-specific binding sites. In SCOS, galectin-1 binding was moderate to strong and more pronounced than galectin-3 binding by Sertoli cells (mean scores 4.00 and 2.25). Tubular walls were negative for galectin-staining. The ratio for galectin-1-/galectin-3-specific binding (staining score ratio) was 1.50 form normal testis and 1.78 for SCOS disclosing a relative increase of galectin-3 binding sites in the latter. Staining with galectin-1- and -3-specific antisera showed a strong cytoplasmic galectin-1 immunoreactivity in Sertoli cells of normal and SCOS testis (score 4.00 for both). Anti-galectin-3 did not stain Sertoli cells or germ cells in normal testis. Only Leydig cells were labeled (score 3.00). In SCOS a weak to moderate nuclear staining of Sertoli cells was noted (score 2.00). Galectin-3 expression and galectin-1-specific binding sites were found to be increased in Sertoli cells of SCOS. This modulation of reactivity can have implications for Sertoli cell interactions with galectin-reactive extracellular matrix components like laminin and for anti-apoptotic effects.

Adult↗
PubMed2000

Expression of the aromatase gene in the human prepubertal testis.

It has been proposed that estrogens might play a negative feedback role in the local regulation of androgen biosynthesis in the testis. Although aromatase has been reported to be present in human adult Leydig cells, CYP19 gene expression in the human prepubertal testis has not been studied. Human prepubertal testicular tissue was obtained from 12 testes collected at necropsy. Ages ranged from 0.07 to 7 years, but 7 of the 12 subjects were younger than 3 months old. Tissue mRNA was subjected to RT-PCR analysis by two methods. Cytochrome P450arom mRNA was detected by non-radioactive RT-PCR in five of the 12 prepubertal testes collected from 0.05-7 year-old subjects, and in one testis collected from a 15 year-old pubertal control. Four of these five prepubertal samples belonged to the youngest infant group. Using a more sensitive, radioactive RT-PCR, aromatase mRNA was detected in all prepubertal testes. This study shows that the CYP19 gene is expressed in the prepubertal human testis including the period of early postnatal activation. It is possible that estrogens may have a role in prepubertal males during this period.

Adolescent↗
PubMed2002

Cancer-testis antigens: promising targets for antigen directed antineoplastic immunotherapy.

During the last decade, the aberrant expression of normal testicular proteins in neoplastically transformed cells became common knowledge. Cancer-testis antigens (CTAs) represent a novel family of immunogenic proteins. The genes MAGE, BAGE, GAGE, LAGE and NY-ESO-1 code for antigens that are recognised on various neoplastically transformed cells by autologous, cytolytic CD8 ( + ) T lymphocytes. The MAGE genes were initially analysed from melanomas and turned out to have an almost exclusively neoplasm specific expression pattern. In normal adult tissues, most 23 human MAGE genes are expressed only in the testis, with expression patterns suggesting that this gene family is involved in germ cell development. The SSX (synovial sarcoma on X chromosome) gene family, located on the X chromosome, encode a family of highly homologous nuclear proteins. A number of observations confirmed that all five SSX genes were expressed in normal testis. The newly detected CTA, NY-ESO-1, is regarded as one of the most immunogenic antigens ever isolated, inducing spontaneous host immune responses in 50% of patients with NY-ESO-1-expressing neoplasms. The identification of neoplasm-associated markers recognised by cellular or humoral effectors of the immune system has opened new perspectives for antigen directed, individualised antineoplastic immunotherapy. In preparation for this new era of targeted immunotherapy, a number of neoplasm-associated antigen families have been identified as targets for CD8+, cytolytic T lymphocytes in vitro and in vivo : (1) CTAs expressed in various neoplasms and in normal testis, restricted to male germ cells; (2) melanocyte differentiation antigens; (3) point mutations of normal genes; (4) antigens overexpressed in neoplastic tissues; and (5) viral antigens. Immunotherapeutic protocols directed against the CTAs have already been initiated to analyse the induction of antigen-specific cellular and humoral immune responses in vivo.

Antigens↗
PubMed1994

Fetal testis--a very special endocrine organ.

The fetal testis is a special organ endocrinologically and not at all like a smaller version of the adult testis. Unlike the quiescent fetal ovary, its hormone production is very active. Besides testosterone it produces a special 'fetal gonadal hormone', the anti-Müllerian hormone. These two hormones together play a key role in the induction and regulation of male sexual differentiation. To meet these functional requirements the fetal testis has many unique features, especially as regards luteinizing hormone and follicle-stimulating hormone action, which discriminate it from the respective functions of the adult testis. In this article, some enigmatic features of fetal testicular endocrine function are concentrated on in an attempt to identify the most important questions for further research.

Animals↗
PubMed1994

Effect of thyroid status on the oxidative capacity of Sertoli cells isolated from immature rat testis.

Our previous studies indicate the Sertoli cell as a target for thyroid hormone action at testis level. In the present study we evaluated the effect of thyroid hormone on Sertoli cell oxidative capacity measured by specific cytochrome oxidase (COX) activity and intracellular adenosine triphosphate (ATP) content. Sertoli cells were isolated from 21-day-old rats. Hypothyroidism, induced from the day of birth by administration of 0.025% methimazole, was characterized by a severe delay of body and testis growth and resulted in a lower COX activity (-40%, p < or = 0.01) and a lower ATP content (-35%, p < or = 0.01) by isolated Sertoli cells. Administration of triiodothyronine (10 micrograms/100 g body wt on alternate days) to hypothyroid rats improved body and testis growth and restored both COX activity and ATP content. The presence of high-affinity, low-capacity binding sites for triiodothyronine in Sertoli cell mitochondria also was demonstrated. This study, unlike that carried out on the whole testis from adult rats, demonstrates that thyroid hormone affects the energy metabolism of Sertoli cells from midpubertal rat testes.

Adenosine Triphosphate↗
PubMed2005

Differential expression of p160 steroid receptor coactivators in the rat testis and epididymis.

OBJECTIVE: Androgens are critical for the development and maintenance of male sexual characteristics. Their action is mediated through the androgen receptor (AR). Ligand-bound AR interacts with coactivator proteins that mediate transcriptional activation. Such coactivators include three members of the 160 kDa proteins (p160s): SRC-1, TIF2/GRIP1, and p/CIP/RAC3/ACTR/AIB1/TRAM-1. The aim of this study was to investigate the expression of the three p160 coactivators and their association with AR in testis and epididymis. METHODS: We determined the localization of these three p160 coactivators in immature and mature rat testis, and epididymis by immunohistochemistry using the specific monoclonal antibodies. We also performed double immunofluorescence staining to examine whether p160s are colocalized with AR in these tissues. RESULTS: In seminiferous tubules of mature rat testis, SRC-1 and TRAM-1 immunoreactivity was found predominantly in spermatogonia and spermatocytes. In contrast, TIF2 was expressed predominantly in Sertoli cells. AR was coexpressed with TIF2 in this cell type. In immature rat testis, however, all three coactivators were expressed in both germ cells and Sertoli cells. In the epididymis, SRC-1 and TIF2 immunoreactivities were localized in nuclei of epithelial cells. However, TRAM-1 immunostaining was observed in the luminal portion of the cytoplasm with greater intensity than in the nucleus, especially in the caput epididymidis. CONCLUSIONS: The cell-type-specific expression of p160 coactivators suggests specific roles in male reproductive organs. Further, the strong cytoplasmic localization of TRAM-1 protein in epithelial cells of epididymis suggests that TRAM-1 may have additional role(s) in transcriptional regulation.

Aging↗
PubMed1975

Cellular and subcellular compartmentalization of steroid metabolism in the rat testis.

The following aspects are discussed in relation to the cellular and subcellular localization of steroid metabolism in the rat testis: (1) the localization of enzyme activities for steroid production in interstitial tissue and seminiferous tubules in intact cells and in isolated mitochondrial fractions: (2) steroid production by isolated cellular and subcellular fractions and by the intact testis in vivo; and (3) the effect of cofactors on steroid production by rat testis preparations in vitro. It is concluded that it is difficult to decide whether steroid production and the enzymes involved in steroid metabolism are restricted to specific compartments. Steroid production by the testis can, however, be quantitatively explained by that occurring in the isolated mitochondria of the interstitial tissue.

Animals↗
PubMed1997

Age-related changes in peripheral hormone concentrations and their relationships with testis size and number of Sertoli and germ cells in yearling beef bulls.

A study was conducted to determine whether basal or GnRH-stimulated concentrations of FSH, LH, testosterone, androstenedione and oestradiol measured from 2 months to 12 months of age were correlated with size and histology of the testes of Angus bulls at 12 months of age. Three blood samples per month were taken from 24 calves at 1.5 h intervals to establish basal hormone concentrations. On the following day, calves received 0.05 microgram of GnRH kg-1 body mass and were bled 1.5 h and 3.0 h later. At 12 months of age, bulls were castrated and testes were measured and prepared for histological analysis. Yearling testis diameter was related to GnRH-stimulated testosterone at 3 months (r = 0.48, P < 0.05). Basal FSH at all ages between 2 months and 12 months was correlated with yearling testis diameter (r = -0.53, P < 0.05, to r = -0.74, P < 0.01). In addition, basal FSH, measured at 2 and 3 months and between 8 and 12 months, was related to number of Sertoli cells per testis (r = -0.47, P < 0.05, to r = -0.53, P < 0.05), number of round spermatids per A1 spermatogonium (r = -0.48, P < 0.05, to r = -0.60, P < 0.01) and number of round spermatids per Sertoli cell (r = -0.50, P < 0.05, to r = -0.64, P < 0.01). Similarly, prepubertal concentrations of GnRH-stimulated FSH between 2 months and 12 months of age were correlated with testis diameter (r = non-significant, to r = -0.71, P < 0.01) and cell ratios in the seminiferous tubules (r = non-significant, to r = -0.61, P < 0.01). Thus, prepubertal hormone secretion could serve as a meaningful index of the potential sperm-producing capacity of the yearling bull.

Aging↗