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Large cell calcifying Sertoli cell tumour of the testis.

Five cases of large cell calcifying Sertoli cell tumour of the testis not associated with complex dysplastic syndromes are reported. The age of the patients ranged from 13 to 34 years and all the tumours were histologically similar, having large, isomorphic, non-mitotic, eosinophilic Sertoli cells with foci of calcification. Flow cytometry demonstrated the cells to be diploid or hypodiploid. All cases were positive for vimentin and focally positive for low molecular weight keratin. The present cases, together with a review of the 22 previously reported tumours, demonstrate that there are two clear cut types of large cell calcifying Sertoli cell tumour; those which are associated with complex dysplastic syndromes and which are bilateral and multifocal, and those which are not associated and are unilateral and focal. Prognosis in all of our cases was uniformly good despite invasion of the rete testis in two cases. It is considered that conservative resection of the tumour is the treatment of choice in cases not associated with complex dysplastic syndromes, since the malignancy rate is low.

Adolescent↗

High TGFbeta1, estrogen receptor, and aromatase gene expression in a large cell calcifying sertoli cell tumor (LCCSCT): implications for the mechanism of oncogenesis.

Large cell calcifying Sertoli cell tumors (LCCSCT) are associated with Carney complex and Peutz-Jeghers syndrome. The mechanisms linking these 2 genetic defects to the genesis of this tumor are obscure. Studies of CYP19 (aromatase) and transforming growth factor (TGF)-beta1 messenger RNA (mRNA) abundance, estrogen receptor (ER), TGFbeta1, and TGFbeta type II receptor (R) immunochemistry were carried out in the testis of a patient with this tumor to gain information on possible mechanisms of cell tumor development. Testicular tissue of a prepubertal patient, collected at gonadectomy, was separated into 2 macroscopically distinct fractions: tumoral nodules (Tu) and extratumoral, normal-looking testicular tissue (ExTu). The patient was a 9.5-year-old boy with a 5-year history of bilateral gynecomastia (Tanner stage 4), no pubic hair, incipient genital development, and bilateral testicular nodules. Multiple pigmented lesions of the skin were present. Bilateral mammectomy and gonadectomy was performed. RNA was extracted from Tu and ExTu for semiquantitative reverse transcriptase-polymerase chain reaction of CYP19 and TGFbeta1. Protein expression of ER, TGFbeta1, and TGFbeta type II R in Tu and ExTu was detected by immunohistochemistry. Cell proliferation was estimated by Ki-67 antigen immunochemistry and apoptosis using a modified TUNEL assay. Mean expression of aromatase and TGFbeta1 mRNAs in Tu was 6- and 2.3-fold higher than in ExTu, respectively (P<0.05). Tumoral cells exhibited ER staining with a predominant extranuclear localization. Positive staining of Sertoli cells in Tu was higher than in ExTu. TGFbeta1 immunostaining of the interstitial cells in Tu was higher than in ExTu. TGFbeta type II R immunostaining was detected in most Sertoli and interstitial cells, but intensity in ExTu was lower than in Tu. No significant difference was detected in the proliferation index, but in Tu, the percentage of Sertoli cells in apoptosis (1.4%) was significantly lower (P<0.01) than in ExTu (14.0%). The following hypothesis is proposed. The congenital gene defects of Carney complex or of Peutz-Jeghers syndrome might trigger a cascade of intracellular events that leads to overexpression of aromatase in Sertoli cells, favoring the development of a LCCSCT. At some point in the evolution of the disease, a mutational event might induce a higher expression of the ER. Also, TGFbeta1 protein expression is increased in neighboring cells. In this environment, TGFbeta1 might switch from tumor suppressor to oncogenic factor and, along with estrogen-ER complexes, might favor tumor progression by inhibiting apoptosis.

Apoptosis↗

Collagen increases the synthesis of membrane-associated proteoglycans produced by Sertoli cells.

Sertoli cells in culture produce two isoforms of proteoglycans which are found in the culture medium and associated with the cell membrane. The amount of both types of proteoglycans increased when Sertoli cells were plated on type I collagen-coated dishes as compared to uncoated dishes. The effect is due to an increase in the synthesis of proteoglycans rather than a diminished rate of degradation of these molecules. The collagen substrate also affects the distribution of these macromolecules; an increase in the amount of membrane-associated proteoglycans occurs at the expense of the proteoglycans released to the culture medium.

Animals↗

Identification of a non-mitogenic paracrine factor involved in mesenchymal-epithelial cell interactions between testicular peritubular cells and Sertoli cells.

Seminiferous peritubular cells have previously been shown to secrete a protein termed P-Mod-S which modulates the functions of Sertoli cells. The present study provides an initial characterization of P-Mod-S and examines the actions of P-Mod-S on Sertoli cells. Gel filtration chromatography demonstrates that P-Mod-S has an apparent molecular weight of 70 000 that could not be dissociated to a lower molecular weight form. A 40- to 90-fold purification of P-Mod-S was obtained with a predicted half maximal effective concentration for Sertoli cells of less than 10(-9) M. Through an analysis of the actions of P-Mod-S on Sertoli cells it is demonstrated that P-Mod-S stimulates the Sertoli cell to a greater extent than any single hormone or vitamin known to influence the cell. P-Mod-S maximally stimulates testicular transferrin and androgen-binding protein production by Sertoli cells, but does not stimulate levels of plasminogen activator activity. P-Mod-S also appears to induce the synthesis of several proteins that are not detected in control non-treated Sertoli cell cultures. One such protein whose synthesis was stimulated by P-Mod-S treatment of Sertoli cells was a component having a molecular mass of 20 kDa. This 20 kDa Sertoli cell-secreted protein was specifically immunoprecipitated with an antibody against an epididymal lactalbumin-like protein. This implies that P-Mod-S can induce Sertoli cells to synthesize and secrete a lactalbumin-like protein. P-Mod-S was found not to contain mitogenic activity. Data presented indicate that testicular peritubular cells synthesize and secrete a 70 kDa non mitogenic paracrine factor termed P-Mod-S which has a dramatic influence on Sertoli cell functions. Results are discussed with respect to modulation of epithelial (Sertoli) cell functions by components produced by mesenchymal (peritubular) cells.

Androgen-Binding Protein↗

Vectorial (transcellular) transport of potassium (86Rb+) by cultured Sertoli cells.

Sertoli cells from rats aged 25 days were grown on Millipore filters (pore diameter 0.5 micron) for 7 days and were then used for determination of transport of 86Rb+ through the cells (base to apex); this procedure is referred to as measuring transcellular or vectorial transport. Sertoli cells were also used to measure apical efflux of 86Rb+ by loading the cells with the isotope to steady state and then incubating cells so that the apical surfaces were in contact with medium not containing 86Rb+, from which samples were taken. Basal efflux was measured in the same way except that the opposite surface of the cells was in contact with the medium. Cells grown on filters treated with collagen IV plus fibronectin showed transcellular transport of 86Rb+; t1/2 for equilibration across the cells was 9-12 min. The rate of transport was accelerated by addition of (Bu)2cAMP, forskolin, or FSH to the incubation medium. Half-maximal responses were seen with (Bu)2cAMP at 0.2 mM and with forskolin at 20 microM. Apical efflux (t1/2 9.8 +/- 2.1 min) was not influenced by the presence or absence of K+ in the medium nor by azide or (Bu)2cAMP. Basal efflux showed similar values for t1/2 in the presence of K+ (9.7 +/- 1.9 min) and values of 21.4 +/- 4.2 min in the absence of K+. Vectorial transport of 86Rb+ by these cells may account for the K+ gradient seen in the seminiferous tubule and appears to result from a basolateral potassium pump together with an apical membrane that is permeable to K+.

Animals↗

Inhibin gene expression in a large cell calcifying Sertoli cell tumour and serum inhibin and activin levels.

Inhibin is a potential tumour suppressor gene product in the gonads. While inhibin gene products may have a role in tumourigenesis, serum inhibin levels can be used as a marker for ovarian tumours derived from granulosa cells. Tumours derived from Sertoli cells, testicular counterparts of granulosa cells, are rare. To assess whether inhibin could be used as a human Sertoli cell tumour marker, serum inhibin and activin levels and inhibin subunit mRNA expression in the testis were studied. Northern blot and in situ hybridization revealed abundant expression of inhibin alpha, beta A, and beta B subunit mRNAs in large cell calcifying Sertoli cell tumours found in a 12-year old boy with Carney complex. The tumours were multifocal and bilateral. Serum inhibin levels were clearly elevated at the time of the diagnosis, decreased by 50% after one of the testes was removed, and were low or undetectable after the second orchidectomy six weeks later. Activin was undetectable before the orchidectomies, while a low concentration of activin-A was measured after them. Follicle stimulating hormone (FSH) concentration increased from normal pubertal value to castration level as expected. Normal seminiferous tubules also showed inhibin subunit alpha and beta B mRNA expression, whereas inhibin beta A mRNA was expressed in normal Leydig cells. These data suggest that serum inhibin reflects Sertoli cell activity and can be used as a human tumour marker.

Activins↗

Large-cell calcifying Sertoli cell tumor of the testis: a case report with ultrastructural study.

Large-cell calcifying Sertoli cell tumor (LCCSCT) is a rare histologic variant of Sertoli cell tumor. Recently we observed a case of LCCSCT of the testis with no associated endocrine abnormality. Our ultrastructural findings of rows of tight junctions, numerous intracytoplasmic filaments, and abundant rough endoplasmic reticulum in whorled formations support the Sertoli cell origin of this neoplasm.

Adult↗

A reassessment of Y chromosomal behaviour in germ cells and Sertoli cells of the mouse as revealed by in situ hybridisation.

In situ hybridisation experiments were carried out to reappraise the state of condensation of the Y chromosome in germ cells and Sertoli cells of the mouse. Previous work had suggested that all testicular cells showed a condensed Y chromosome prior to the adult stage. We now demonstrate that, although the Y chromosome is condensed in pre-pubertal Sertoli cells, it is greatly expanded in primordial germ cells (gonocytes). An expanded Y-signal is first seen in Sertoli cell nuclei at or around day 21 of postnatal development, coinciding with the first appearance of spermatids in the germinal epithelium.

Animals↗

Purification and characterization of testicular transferrin secreted by rat Sertoli cells.

Sertoli cells synthesize and secrete a transferrin-like protein (testicular transferrin) [Skinner & Griswold (1980) J. Biol. Chem. 255, 1923-1925]. The purpose of the present study was to purify and characterize testicular transferrin and to compare it with serum transferrin. Testicular transferrin was obtained from the medium of cultured rat Sertoli cells, whereas serum transferrin was obtained from rat serum. Both proteins were purified with the use of phenyl-Sepharose hydrophobic chromatography and transferrin immunoaffinity chromatography. The purified proteins were shown to have similar molecular masses (75 000 Da) and amino acid compositions. The pattern of tryptic peptides from testicular and serum transferrin were found to be essentially the same when analysed by reverse-phase high-pressure liquid chromatography. The carbohydrate composition of both transferrins was determined by several colorimetric assays and g.l.c. Testicular transferrin, isolated from cell culture medium, had increased amounts of glucose, galactose and glucosamine. Serum transferrin that was incubated with cell culture medium also had a large amount of associated glucose. The results show that testicular transferrin and serum transferrin are structurally very similar and are possibly products of the same gene expressed in two different tissues, the testis and liver. However, the amount of carbohydrate associated with these two proteins is different.

Amino Acids↗

Large cell calcifying Sertoli cell tumor of the testis: contrasting features of six malignant and six benign tumors and a review of the literature.

We report six malignant and six benign large cell calcifying Sertoli cell tumors of the testis and compare the features of malignant and benign cases based on these cases and those in the literature. All the tumors in this report consisted of sheets, nests, solid tubules, and cords of eosinophilic cells, with focal calcifications, as well as a substantial neutrophilic infiltrate in 11 of them. Analysis of our cases and those in the literature showed that the malignant tumors were unilateral and solitary and occurred at a mean age of 39 years (range 28-51 years), whereas the benign neoplasms were bilateral and multifocal in 28% of cases and occurred at a mean age of 17 years (range 2-38 years). Only one malignant tumor occurred in a patient with evidence of a genetic syndrome (Carney syndrome), whereas 36% of benign tumors had various genetic syndromes or endocrine abnormalities. Most of the tumors in the latter cases were bilateral and multifocal. There were strong associations of malignant behavior with size >4 cm, extratesticular growth, gross or microscopic necrosis, high-grade cytologic atypia, vascular space invasion, and mitotic rate greater than three mitoses per 10 high-power fields. All malignant cases exhibited at least two of these features, whereas all benign cases lacked any of them. The presence of any one of these features in a solitary large cell calcifying Sertoli cell tumor, especially in a patient >25 years of age, should be viewed as suspicious for malignant behavior, whereas the presence of two or more of these features indicates a strong probability of a malignant course. "Low" percentages (< or =35%) of tumor cells staining for proliferating cell nuclear antigen (PCNA) also may correlate with benign behavior, but some benign tumors have high PCNA values. Ki-67 values (MIB-1 antibody) did not correlate with biologic behavior, nor did immunostains for p53 protein.

Adolescent↗

Germ cell and Sertoli cell interactions in human testis: evidence for stimulatory and inhibitory effects.

In human Sertoli cell preparations obtained from healthy men (mean age 31.8 +/- 6.8 years; n = 6), we have measured the productions of lactate, 17 beta-oestradiol, transferrin and inhibin between day 4 and day 5 after plating, either in the presence or absence (hypotonic treatment of plated cells on day 2) of germ cells. The results, expressed per 10(6) of cells plated/24 h, showed that lactate production was unchanged, whether or not germ cells were present. However, if we calculated the lactate production per mg protein/24 h, the lactate output was decreased (30-60%) in the presence of germ cells. Whatever the mode of expression, Sertoli cell 17 beta-oestradiol synthesis was diminished 1.5-fold in the presence of germ cells. Conversely, the transferrin output was increased 3.2-fold in non-treated Sertoli cell preparations when compared to the hypotonic-treated plates. A similar observation was recorded for the in-vitro production of inhibin by Sertoli cells, which was enhanced 1.4-fold when germ cells were present. These results, together with a likely potentializing role of germ cells on follicle stimulating hormone control of Sertoli cell function, strongly suggest that germ cells exert both stimulatory and inhibitory effects in regulating human Sertoli cell function through either direct contact and/or via secreted factors.

Adult↗

Stimulation of polyamine biosynthesis by follicle-stimulating hormone in serum-free cultures of rat Sertoli cells.

Sertoli cells derived from 21-day-old rats were cultured in serum-free Ham's F-10 medium to allow a direct investigation of the effects of FSH on polyamine (PA) biosynthesis in a defined culture system. After 48 h in culture, the basal cellular content consisted predominantly of spermine (1.1 nmol/mg protein) with substantially lower amounts of spermidine (0.1 nmol/mg protein) and undetectable amounts of putrescine. Upon the addition of ovine FSH (3 X 10(-9) M), cellular spermine content became significantly elevated above the control value as early as 1 h after treatment, reaching a 2.5-fold stimulation by 4 h. Spermidine was also elevated by 4 h after FSH treatment, but remained less than 20% of the spermine concentration. At no time did the cellular content of putrescine increase to measurable levels. Extended time-course studies demonstrated that the FSH-induced cellular increase in spermine and spermidine content persisted up to 24 h during the continuous presence of FSH. Bu2cAMP (5 mM) invoked similar changes in PA levels when measured at 4, 8, and 24 h. Ornithine decarboxylase (ODC) activity, which catalyzes the production of putrescine, was increased by FSH in a temporal fashion similar to that of spermine production. Addition of alpha-difluoromethylornithine, an irreversible inhibitor of ODC, blocked increases in both ODC activity and PA in cells stimulated with FSH or Bu2cAMP. Pulse-chase experiments using [3H]ornithine demonstrate that putrescine is initially synthesized, and is subsequently converted to spermidine and spermine. These studies suggest that regulation of PA biosynthesis by FSH is largely expressed as increases in spermine, and to a lesser extent spermidine, suggesting that the more complex PAs may be involved in the regulation of Sertoli cell function.

Animals↗

Effect of uncoupling treatments on FSH-induced hyperpolarization of immature rat Sertoli cells from Sertoli cell-enriched cultures.

Sertoli cell-enriched cultures isolated from immature rat testes by enzymic treatments were investigated by intracellular microelectrode recordings. The hyperpolarization of cells induced by FSH was independent of the age of the rats (7-37 days) and was unchanged by exposure to a hormone-free medium or to a glycine buffer of pH 3. It was reduced by treatments which decreased the electrical coupling between cells either by an increase of intracellular calcium [i.e. calcium ionophore (A 23187, 5 x 10(-6) M), general anaesthetic (heptanol, 3.5 mM) and uncoupler of oxidative phosphorylations (carbonylcyanide m-chlorophenylhydrazone-CCmP, 10(-6) M)] or by a decrease of extracellular calcium [i.e. 0Ca + EGTA (1 mM) medium]. These effects were partly or totally reversed by a recovery period in a drug-free medium. Similar results were obtained by an exposure to trypsin (0.05%) followed by a second mechanical dispersion, but new cell hyperpolarization was induced by a new exposure to FSH. This electrophysiological study suggests an initial effect of FSH on the junctional complex between Sertoli cells, then the control by calcium of this complex.

Aging↗

Follicle-stimulating hormone stimulates estradiol-17beta synthesis in cultured Sertoli cells.

Sertoli cells isolated from testes of 20-day-old rats and maintained in primary culture synthesized estradiol-17beta [1,3,5(10)-estratriene-3,17beta-diol] (measured by specific radioimmunoassay) when testosterone (17beta-hydroxy-4-androsten-3-one) 0.5 muM, was added to the culture medium. No detectable estradiol synthesis occurred when cells were incubated in medium containing pregnenolone (3beta-hydroxypregn-5-en-20-one), 0.5 muM, or containing no added steroid substrate. Follicle-stimulating hormone (FSH) (NIH-FSH-S10, 5 mug/ml) stimulated estradiol synthesis 12- to 80-fold when added to medium containing testosterone, but not when added to medium containing pregnenolone or no exogenous steroid substrate. A highly purified FSH preparation, with FSH potency 50 times that of the NIH-FSH, caused a similar stimulation at a concentration of 0.25 mug/ml of medium, whereas luteinizing hormone (NIH-LH-S18, 5 MUG/ML) Caused only marginal stimulation. Dibutyryl-adenosine 3':5' cyclic monophosphate, 0.1 mM, caused a 30-fold increase in estradiol synthesis by Sertoli cells cultured in medium containing testosterone. These studies provide direct demonstration of estradiol-17beta production by Seroli cells from normal animals, and offer evidence that the synthesis of this steroid is regulated at the level of the aromatizing enzyme system by FSH and adenosine 3':5' cyclic monophosphate.

Animals↗

De novo synthesis and recycling pathways of sphingomyelin in rat Sertoli cells.

Sertoli cells from 19-day-old rats have two molecular species of sphingomyelin (SM1 and SM2) with different kinetic characteristics and fatty acid composition. Here, we have studied the incorporation of [14C]-choline and [14C]-palmitic acid into SM in presence or absence of fumonisin B1, an inhibitor of ceramide synthesis, and beta-chloroalanine, an inhibitor of sphinganine synthesis. The contributions of de novo synthesis and recycling pathways were estimated by analysis of the inhibition caused by these drugs. SM1 was synthesized more by sphingosine recycling, and SM2 was synthesized principally by ceramide recycling than SM1. De novo synthesis seems to be important for the two SM types, but our results showed that this pathway is more extensively utilized by SM2. In conclusion, using Sertoli cell cultures, we have shown for the first time that in the same cell different molecular species of SM are synthesized by different pathways.

Animals↗

Large cell calcifying Sertoli cell tumor of the testis: comparative immunohistochemical study with Leydig cell tumor.

Large cell calcifying Sertoli cell tumor is a rare type of testicular tumor. Reported herein is a Japanese patient with this tumor not associated with Carney's complex. An 11-year-old boy was admitted to hospital because of left testicular enlargement, and radical orchiectomy was performed. Macroscopically, the tumor was well circumscribed and had a maximum diameter of approximately 2 cm. The cut surface showed a yellow-white solid mass. Histologically, the tumor was composed of large neoplastic cells with abundant eosinophilic cytoplasm with a tubular, trabecular, and solid arrangement and loose myxoid stroma with irregularly shaped calcification. Immunohistochemically, the tumor cells were positive for vimentin, S-100 protein, calretinin, inhibin-alpha, melan-A, and CD10, and type IV collagen and laminin were observed in the extracellular matrix around the tumor cells. The distributions of melan-A, CD10, and mitochondria were characteristically patchy; in contrast, they were diffusely distributed in the cytoplasm in a control case of Leydig cell tumor. The differences in immunostaining patterns for melan-A, CD10, and mitochondria as well as positivity for S-100 protein-beta might be useful diagnostic hallmarks of large cell calcifying Sertoli cell tumor for discrimination from Leydig cell tumor.

Antigens, Neoplasm↗

Different roles of prepubertal and postpubertal germ cells and Sertoli cells in the regulation of serum inhibin B levels.

To elucidate the role of germ cells in the regulation of inhibin B secretion, serum inhibin B levels in prepubertal boys and adult men whom had a concurrent testicular biopsy showing either normal or impaired testicular function were compared. In addition, by immunohistochemistry the cellular localization of the two subunits of inhibin B (alpha and betaB) were examined in adult testicular tissue with normal spermatogenesis, spermatogenic arrest, or Sertoli cell only tubules (SCO) as well as in normal testicular tissue from an infant and a prepubertal boy. Adult men with testicular biopsy showing normal spermatogenesis (n=8) or spermatogenic arrest (n=5) had median inhibin B levels of 148 pg/mL (range, 37-463 pg/mL) and 68 pg/mL (range, 29-186 pg/mL), respectively, corresponding to normal or near-normal levels of our reference population (165 and 31-443 pg/mL; n=358). Men with SCO (n=9) had undetectable or barely detectable (n=1) serum levels of inhibin B. In contrast to adults, prepubertal boys with SCO (n=12) all had measurable serum inhibin B levels that corresponded to our previously determined normal range in healthy prepubertal boys (n=114). However, in postpubertal samples from the same SCO boys, inhibin B levels were undetectable as in the adult SCO men. Intense inhibin alpha-subunit immunostaining was evident in Sertoli cells in both prepubertal and adult testes. In the prepubertal testis, positive immunostaining for the betaB-subunit was observed in Sertoli cells. In the adult testis, intense immunostaining for the betaB-subunit was evident in germ cells from the pachytene spermatocyte to early spermatid stages and to a lesser degree in Leydig cells, but not in Sertoli cells or other stages of germ cells. Thus, surprisingly, in adult men the two subunits constituting inhibin B were expressed by different cell types. We speculate that during puberty Sertoli cell maturation induces a change in inhibin subunit expression. Thus, immature Sertoli cells express both alpha and betaB inhibin subunits, whereas fully differentiated Sertoli cells only express the alpha-subunit. The correlation in adult men between serum inhibin B levels and spermatogenesis may be due to the fact that inhibin B in adult men is possibly a joint product of Sertoli cells and germ cells, including the stages from pachytene spermatocytes to early spermatids.

Adult↗

Polyamine profiles in rat testis, germ cells and Sertoli cells during testicular maturation.

Polyamine cellular concentrations (putrescine, spermidine and spermine) in the rat testis and testicular cell types were determined by fluorescence spectroscopy of their dansyl derivatives. A method is described to separate dansylated polyamines by high performance liquid chromatography in less than 12 minutes. In rat Sertoli cells, polyamine concentrations (per mg DNA) were greater than those in germ cells and the testis. The concentrations of all three polyamines increased with age. Concentrations of spermidine and spermine in germ cells also increased with age and leveled off after 27 to 35 days. On the other hand, higher putrescine levels were found in the testis of young rats (13 to 22 days) while the greatest spermidine and spermine contents were observed in the testis from rats of 31 to 35 days old. Of great interest, Sertoli cells from all age groups studied released a relatively large quantity of putrescine and a smaller amount of spermidine, but no spermine, into culture media. The amount of polyamine released by Sertoli cells varied with the age of the animal. Sertoli cells from 27-day-old rats released the greatest quantity of putrescine on a per mg DNA basis. The release of putrescine increased after hypotonic treatment that removed contaminating germ cells from the remaining Sertoli cells. It is concluded that cellular polyamine levels in the rat testis, germ cells and cultured Sertoli cells and the amount of polyamines released by Sertoli cells were age-dependent during the first wave of spermatogenesis.

Aging↗