Mitotane treatment in patients with metastatic testicular Leydig cell tumor associated with severe androgen excess.

Mitotane (o,p'DDD) is established in the adjuvant and advanced-stage treatment of adrenocortical carcinoma and counteracts both tumor growth and tumor-related steroid production. Both the adrenal glands and the gonads are steroidogenically active organs and share a common embryogenic origin. Here, we describe the effects of mitotane in two patients with metastatic Leydig cell tumor (LCT) of the testes and associated severe androgen excess (serum testosterone 93 and 88 nmol/L, respectively; male reference range 7-27 nmol/L). Both men suffered from severe restlessness, insomnia and irritability, which they described as intolerable and disrupting normal life activities. Urinary steroid profiling by gas chromatography-mass spectrometry (GC-MS) confirmed excess androgen production and revealed concurrent overproduction of glucocorticoids and glucocorticoid precursors, which under physiological conditions are produced only by the adrenal glands but not by the gonads. In a palliative approach, they were commenced on mitotane, which achieved swift control of the hormone excess and the debilitating clinical symptoms, restoring normal quality of life. GC-MS demonstrated normalization of steroid production and decreased 5α-reductase activity, resulting in decreased androgen activation, and imaging demonstrated disease stabilization for 4-10 months. In conclusion, mitotane can be highly effective in controlling steroid excess in metastatic LCTs, with anti-tumor activity in some cases.

Histamine H4 receptor as a novel therapeutic target for the treatment of Leydig-cell tumours in prepubertal boys.

Leydig-cell tumours (LCTs) are rare endocrine tumours of the testicular interstitium, with recent increased incidence. Symptoms include precocious puberty in children; and erectile dysfunction, infertility and/or gynaecomastia, in adults. So far, scientific evidence points to aromatase (CYP19) overexpression and excessive oestrogen and insulin-like growth factor (IGF) -1 production as responsible for Leydig-cell tumourigenesis. LCTs are usually benign; however, malignant LCTs respond poorly to chemo/radiotherapy, highlighting the need to identify novel targets for treatment. Herein, we investigated the potential role of the histamine receptor H4 (HRH4) as a therapeutic target for LCTs using R2C rat Leydig tumour cells, a well-documented in vitro model for Leydigioma. Also, we studied for the first time the expression of CYP19, IGF-1R, oestrogen receptor (ER) α, ERß, androgen receptor (AR) and HRH4 in human prepubertal LCTs versus normal prepubertal testes (NPTs). HRH4 agonist treatment inhibited steroidogenesis and proliferation in R2C cells and also negatively affected their pro-angiogenic capacity in vitro and in vivo, as assessed by evaluating the proliferative activity of human umbilical vein endothelial cells and by means of the quail chorioallantoic membrane assay, respectively. Moreover, E2 and IGF-1 inhibited HRH4 mRNA and protein levels. In human prepubertal LCTs, CYP19, IGF-1R, ERα and ERß were overexpressed compared with NPTs. In contrast, HRH4 staining was weak in LCTs, but moderate/strong and confined to the interstitium in NPTs. Importantly, HRH4 was absent or barely detectable in seminiferous tubules or germ cells. Overall, our results point to HRH4 as a novel therapeutic target in LCTs.

[Testicular malignant Leydig cell tumor: A case report].

OBJECTIVE: To investigate the clinicopathological features of testicular malignant Leydig cell tumor (TMLCT) and improve the non-invasive diagnosis of the disease. METHODS: We retrospectively analyzed the clinicopathological data on a case of TMLCT, detected the circulating tumor cells (CTC) in the peripheral venous blood, and reviewed the related literature. RESULTS: The patient, a 47-year-old male, underwent radical orchidoepididymectomy under general anesthesia. Postoperative pathology confirmed the lesion to be TMLCT, which was mainly composed of Leydig cells and suspected with vessel carcinoma embolus. Immunohistochemistry showed the tumor cells to be positive for α-inhibin, Ki67, CD30, vimentin, EMA, and PLAP, but negative for CK, CK7, S100, CD10, SMA, Des, AFP, hCG, CEA, CK19, CD117, Oct-4, LCA, CD20, Pax-5, CD3, and CD43. Two CTCs were detected in the peripheral venous blood. The patient received 3 courses of chemotherapy for retroperitoneal multiple lymph nodes metastasis post-operatively. Subsequent CT imaging manifested no obvious reduction of the retroperitoneal lymph nodes and consequently the patient again underwent retroperitoneal lymphadenectomy and cryoablation. At 8 months after treatment, CT examination revealed notably enlarged retroperitoneal lymph nodes with the right adrenal gland evidently invaded. CONCLUSION: TMLCT is an extremely rare sex-gonad stromal tumor with high malignancy and poor prognosis, and CTCs may be used for its early diagnosis and prognostic prediction.

Glucocorticoid Receptor as a Potential Target to Decrease Aromatase Expression and Inhibit Leydig Tumor Growth.

Leydig cell tumors are the most frequent interstitial neoplasms of the testis with increased incidence in recent years. They are hormonally active and are considered one of the steroid-secreting tumors. Although usually benign, the malignant phenotype responds poorly to conventional chemotherapy or radiation, highlighting the need to identify new therapeutic targets for treatment. Here, we identified a novel glucocorticoid-mediated mechanism that controls cell growth in Leydig cell tumors. We found that a synthetic glucocorticoid receptor agonist, dexamethasone, reduces cell proliferation in rat Leydig tumor cells by decreasing the expression and the enzymatic activity of the estrogen-producing enzyme aromatase. This inhibitory effect relies on the ability of activated glucocorticoid receptor to regulate the aromatase gene transcriptional activity through the recruitment of nuclear receptor corepressor protein and silencing mediator of retinoid and thyroid hormone receptors to a newly identified putative glucocorticoid responsive element within the aromatase promoter II. Our in vivo studies reveal a reduction of tumor growth, after dexamethasone treatment, in animal xenografts. Tumors from dexamethasone-treated mice exhibit a decrease in the expression of the proliferation marker Ki-67 and the aromatase enzyme. Our data demonstrate that activated glucocorticoid receptor, decreasing aromatase expression, induces Leydig tumor regression both in vitro and in vivo, suggesting that glucocorticoid receptor might be a potential target for the therapy of Leydig cell tumors.

[Gefitineb inhibits the growth and induces the apoptosis of mouse I-10 Leydig testicular cancer cells in vitro].

OBJECTIVE: To observe the inhibitory effect of gefitineb on the proliferation and its inducing effect on the apoptosis of mouse I-10 Leydig testicular cancer cells in vitro. METHODS: We treated I-10 Leydig testicular cancer cells of mice with gefitineb at 0, 1.25, 2.5, 5, 10, 20, and 40 µmol/L. Then we determined the inhibitory effect of gefitineb on the growth of the cells by MTT, detected their early and late apoptosis by Annexin V-FITC/propidium iodide double staining and Hoechst 33258 nuclear staining, respectively, and observed the expressions of apoptosis-related proteins Bcl-2, Bax and caspase 3/9 by Western blot. RESULTS: Compared with the blank control group, gefitineb significantly inhibited the proliferation of the I-10 cells at 10 and 20 µmol/L (P < 0.05). The survival rate of the cells was (32.4 ± 2.8)% (P < 0.01) and their early and late apoptosis rates were (26.7 ± 4.2)% and (59.33 ± 10.2)% in the 40 µmol/L group, significantly different from those in the control (P < 0.05 and P <0.01). In comparison with the blank control group, gefitineb at 10, 20, and 40 µmol/L increased the expression of pro-apoptotic protein Bax by (41.9 ± 7.1), (60.1 ± 9.8), and (69.0 ± 11.3)% (all P < 0.05), decreased that of apoptosis-inhibitory protein Bcl-2 by (50.3 ± 8.9), (63.9 ± 6.9), and (88.7 ± 13.9)% (all P < 0.05), and elevated that of the cleft proteins caspase-3 by (69.0 ± 6.9)% (P < 0.05), (71.5 ± 8.1)% (P < 0.05), and (110.9 ± 14.2)% (P < 0.01) and caspase-9 by (51.8 ± 4.9), (54.7 ± 6.7), and (43.8 ± 11.8)% (all P < 0.05). CONCLUSION: Gefitineb can increase the cytotoxicity of I-10 Leydig testicular cancer cells of mice and induce their apoptosis via the mitochondria-mediated apoptosis signaling pathway.

Cordycepin induced MA-10 mouse Leydig tumor cell apoptosis by regulating p38 MAPKs and PI3K/AKT signaling pathways.

The p38 MAPKs play important roles in the regulation of balance between cell survival and cell death on the development of various cancers. However, the roles of p38 MAPKs regulating apoptotic effects on Leydig tumor cells remain unclear. In the present study, we showed that cordycepin (3'-deoxyadenosine) selectively induced apoptosis in MA-10 mouse Leydig tumor cells through regulating the p38 MAPK and PI3K/AKT signaling pathways. Cordycepin reduced viability in MA-10, TM4, and NT2/D1 cells, but not cause cell death of primary mouse Leydig cells on moderate concentration. Cordycepin increased reactive oxygen species (ROS) levels, which is associated with the induction of apoptosis as characterized by positive Annexin V binding, activation of caspase-3, and cleavage of PARP. Inhibition of p38 MAPKs activity by SB203580 significantly prevented cordycepin-induced apoptosis in MA-10 cells. Co-treatment with wortmannin or the autophagy inhibitor 3-methyladenine (3-MA) elevated levels of apoptosis in cordycepin-treated MA-10 cells. Moreover, cordycepin activated p53, p21 and TGFß; and downregulated CDK2. The antitumour activity of cordycepin-treated MA-10 cells was significantly distinct in severe combined immunodeficiency (SCID) mice in vivo. These results suggested that cordycein is a highly selective treatment to induce MA-10 cells apoptosis via p38 MAPKs signaling.

2-Phenylimidazo[1,2-a]pyridine-containing ligands of the 18-kDa translocator protein (TSPO) behave as agonists and antagonists of steroidogenesis in a mouse leydig tumor cell line.

Ligands of 18-kDa translocator protein (TSPO) are known for their ability to potently and dose-dependently stimulate steroid biosynthesis in steroidogenic cells. In this study, we investigated a number of 2-phenyl-imidazo[1,2-a]pyridine acetamide derivatives, analogs of alpidem, for their ability to bind TSPO and to affect steroidogenesis in a mouse Leydig tumor cell line. We observed that not only some compounds behaved as agonists, stimulating steroidogenesis (e.g., 3 and 4) with EC50 values (15.9 and 6.99µM) close to that determined for FGIN-1-27 used as positive control (7.24µM), but two compounds, namely 5 and 6, which on the other hand are the most lipophilic ones in the investigated series, behaved as antagonists, by significantly inhibiting steroid production at concentrations at least twenty times lower than the cytotoxic ones. To our surprise, the newly synthesized compound 3, which is a strict analog of alpidem bearing at the para position of the 2-phenyl group a methoxy group instead of chlorine, achieved a ten-fold stimulation of the steroid production (for comparison FGIN-1-27 achieved 1.6-fold stimulation). Within the limits of the examined property space, some unprecedented SARs were unveiled, which can help in understanding the key molecular factors underlying the transition from agonism to antagonism in the steroidogenesis process. Besides the substitution pattern and the physicochemical features (mainly hydrogen bonding potential) of the substituents at the positions C(6) and C(8) of the imidazo[1,2-a]pyridine nucleus, and at the para position of the 2-phenyl group, the structure-activity relationship analysis suggested lipophilicity, whose increase seems to be generally related to steroidogenesis inhibition, and steric hindrance, which appeared as a stimulation-limiting factor, as two main properties to control in the design or optimization of novel imidazo[1,2-a]pyridine-based TSPO ligands endowed with potential in modulating the steroidogenesis process.

Annexin V-induced rat Leydig cell proliferation involves Ect2 via RhoA/ROCK signaling pathway.

This study investigated the effect of annexin V on the proliferation of primary rat Leydig cells and the potential mechanism. Our results showed that annexin V promoted rat Leydig cell proliferation and cell cycle progression in a dose- and time-dependent manner. Increased level of annexin V also enhanced Ect2 protein expression. However, siRNA knockdown of Ect2 attenuated annexin V-induced proliferation of rat Leydig cells. Taken together, these data suggest that increased level of annexin V induced rat Leydig cell proliferation and cell cycle progression via Ect2. Since RhoA activity was increased following Ect2 activation, we further investigated whether Ect2 was involved in annexin V-induced proliferation via the RhoA/ROCK pathway, and the results showed that annexin V increased RhoA activity too, and this effect was abolished by the knockdown of Ect2. Moreover, inhibition of the RhoA/ROCK pathway by a ROCK inhibitor, Y27632, also attenuated annexin V-induced proliferation and cell cycle progression. We thus conclude that Ect2 is involved in annexin V-induced rat Leydig cell proliferation through the RhoA/ROCK pathway.

Androgens inhibit aromatase expression through DAX-1: insights into the molecular link between hormone balance and Leydig cancer development.

Leydig cell tumors (LCTs) of the testis are steroid-secreting tumors associated with various steroid biosynthetic abnormalities and endocrine dysfunctions. Despite their overall rarity, LCTs are still of substantial interest owing to the paucity of information regarding their exact nature and malignant potential. In the present study, we disclose the ability of androgens to inhibit Leydig tumor cell proliferation by opposing to self-sufficient in situ estrogen production. In rat Leydig tumor cells, R2C, androgen treatment significantly decreases the expression and the enzymatic activity of cytocrome P450 aromatase, responsible for the local conversion of androgens into estrogens. This inhibitory effect relies on androgen receptor (AR) activation and involves negative regulation of the CYP19 gene transcriptional activity through the nuclear orphan receptor DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1). Ligand-activated AR up-regulates the expression of DAX-1 and promotes its increased recruitment within the steroidogenic factor-1 site-containing region of the aromatase proximal promoter II in association with the nuclear receptor corepressor. The biological relevance in LCTs of the newly highlighted functional interplay between AR, DAX-1, and aromatase is underlined by our in vivo observations, revealing a marked down-regulation of AR and DAX-1 expression and a strong increase in aromatase levels in testes tissues from old Fischer rats with spontaneously developed Leydig cell neoplasia, compared with normal testes tissues from younger animals. In elucidating a mechanism by which androgens modulate the growth of Leydig tumor cells, our finding support the hypothesis that maintaining the adequate balance between androgen and estrogens may represent the key for blocking estrogen-secreting Leydigioma development, opening new prospects for therapeutic intervention.

Cooperation of histone deacetylase inhibitors SAHA and valproic acid in promoting sodium/iodide symporter expression and function in rat Leydig testicular carcinoma cells.

The presence of the sodium/iodide symporter (NIS) is the prerequisite for the use of the radioiodine in the treatment of thyroid cancer. Thus, stimulators of NIS expression and function are currently investigated in cellular models of various human malignancies, also including extrathyroid cancers. In this study, we analyzed the effects of the histone deacetylase inhibitors (HDACi), suberoylanilide hydroxamic acid (SAHA) and valproic acid (VPA), on NIS expression and function in rat Leydig testicular carcinoma cells (LC540). LC540 cells were exposed to SAHA 3 µM and VPA 3 mM (alone and in combination), and cell viability evaluated by MTT assay and cell counting, NIS mRNA and protein levels by using, respectively, real-time RT-PCR and western blotting. NIS function was evaluated by iodide uptake assay. We found that both HDACi were able to stimulate the transcription of NIS gene, but not its protein expression, while the association of SAHA and VPA increased both NIS transcript and protein levels, resulting in significant sixfold enhancement of radioiodine uptake capacity of LC540 cells. These data demonstrate the presence of an epigenetic control of NIS expression in Leydig tumor cells, suggesting the possibility to use the combination of these two HDACi for a radioiodine-based treatment of these malignancies.

Selective GPER activation decreases proliferation and activates apoptosis in tumor Leydig cells.

We have previously shown that estrogens binding to estrogen receptor (ER) α increase proliferation of Leydig tumor cells. Estrogens can also bind to G protein-coupled ER (GPER) and activation of this receptor can either increase or decrease cell proliferation of several tumor types. The aim of this study was to investigate GPER expression in R2C rat tumor Leydig cells, evaluate effects of its activation on Leydig tumor cell proliferation and define the molecular mechanisms triggered in response to its activation. R2C cells express GPER and its activation, using the specific ligand G-1, is associated with decreased cell proliferation and initiation of apoptosis. Apoptosis after G-1 treatment was asserted by appearance of DNA condensation and fragmentation, decrease in Bcl-2 and increase in Bax expression, cytochrome c release, caspase and poly (ADP-ribose) polymerase-1 (PARP-1) activation. These effects were dependent on GPER activation because after silencing of the gene, using a specific small interfering RNA, cyt c release, PARP-1 activation and decrease in cell proliferation were abrogated. These events required a rapid, however, sustained extracellular regulated kinase 1/2 activation. G-1 was able to decrease the growth of R2C xenograft tumors in CD1 nude mice while increasing the number of apoptotic cells. In addition, in vivo administration of G-1 to male CD1 mice did not cause any alteration in testicular morphology, while cisplatin, the cytotoxic drug currently used for the therapy of Leydig tumors, severely damaged testicular structure, an event associated with infertility in cisplatin-treated patients. These observations indicate that GPER targeting for the therapy of Leydig cell tumor may represent a good alternative to cisplatin to preserve fertility in Leydig tumor patients.

Simvastatin-induced up-regulation of gap junctions composed of connexin 43 sensitize Leydig tumor cells to etoposide: an involvement of PKC pathway.

Some of lipophilic statins have been reported to enhance toxicities induced by antineoplastic agents but the underling mechanism is unclear. The authors investigated the involvement of Cx43-mediated gap junction intercellular communication (GJIC) in the effect of simvastatin on the cellular toxicity induced by etoposide in this study. The results showed that a major component of the cytotoxicity of therapeutic levels of etoposide is mediated by gap junctions composed of connexin 43(Cx43) and simvastatin at the dosage which does not induce cytotoxicity enhances etoposide toxicity by increasing gap junction coupling. The augmentative effect of simvastatin on GJIC was related to the inhibition of PKC-mediated Cx43 phosphorylation at ser368 and subsequent enhancement of Cx43 membrane location induced by the agent. The present study suggests the possibility that upregulation of gap junctions may be utilized to increase the efficacy of anticancer chemotherapies.

Inhibition of Leydig tumor growth by farnesoid X receptor activation: the in vitro and in vivo basis for a novel therapeutic strategy.

Leydig cell tumors (LCTs) are the most common tumors of the gonadal stroma and represent about 3% of all testicular neoplasms. In most cases, LCTs are benign; however, if the tumor is malignant, no effective treatments are currently available. We have recently reported that farnesoid X receptor (FXR) is expressed in R2C Leydig tumor cells, and it reduces the estrogen-dependent cell proliferation by negatively regulating aromatase expression. Here, we demonstrated that treatment with GW4064, a specific FXR agonist, markedly reduced Leydig tumor growth in vivo by inhibiting proliferation and inducing apoptosis. Indeed, the tumors from GW4064-treated mice exhibited a decrease in the expression of the proliferation marker Ki-67 and aromatase along with an increase in the apoptotic nuclei. FXR activation induced an enhanced poly(ADP-ribose) polymerase cleavage, a marked DNA fragmentation and a strong increase in TUNEL-positive R2C cells also in vitro. Moreover, in both in vivo and in vitro models, FXR ligands upregulated mRNA and protein levels of p53 and of its downstream effector p21(WAF1/Cip1) . Functional experiments showed that FXR ligands upregulated p53 promoter activity and this occurred through an increased binding of FXR/nuclear factor-kB (NF-kB) complex to the NF-kB site located within p53 promoter region as revealed by electrophoretic mobility shift assay and chromatin immunoprecipitation analysis. Taken together, results from our study show, for the first time, that treatment with FXR ligands induces Leydig tumor regression in vivo, suggesting that activation of FXR may represent a promising therapeutic strategy for LCTs.

Proliferative effect of histamine on MA-10 Leydig tumor cells mediated through HRH2 activation, transient elevation in cAMP production, and increased extracellular signal-regulated kinase phosphorylation levels.

Mast cells (MC) occur normally in the testis with a species-specific distribution, yet their precise role remains unclear. Testicular MC express histidine decarboxylase (HDC), the unique enzyme responsible for histamine (HA) generation. Evidence to date supports a role for HA as a local regulator of steroidogenesis via functional H1 and H2 receptor subtypes (HRH1 and HRH2, respectively) present in Leydig cells. Given that HA is a well-known modulator of physiological and pathological proliferation in many different cell types, we aimed in the present study to evaluate whether HA might contribute to the regulation of Leydig cell number as well as to the control of androgen production. Herein, we demonstrate, to our knowledge for the first time, that MA-10 Leydig tumor cells, but not normal immature Leydig cells (ILC), exhibit a proliferative response upon stimulation with HA that involves HRH2 activation, transient elevation of cAMP levels, and increased extracellular signal-regulated kinase (ERK) phosphorylation. Our results also reveal that MA-10 cells show significantly heightened HDC expression compared to normal ILC or whole-testicular lysate and that inhibition of HDC activity decreases MA-10 cell proliferation, suggesting a possible correlation between autocrine overproduction of HA and abnormally increased proliferation in Leydig cells. The facts that germ cells are also both source and target of HA and that multiple testicular cells are susceptible to HA action underline the importance of the present study, which we hope will serve as a first step for further research into regulation of non-MC-related HDC expression within the testis and its significance for testicular function.

Cordycepin stimulated steroidogenesis in MA-10 mouse Leydig tumor cells through the protein kinase C Pathway.

Cordycepin (3'-deoxyadenosine) is an adenosine analogue isolated from Cordyceps sinensis , which is a Chinese herbal medicine known to have many benefits, including adjustment of the physical condition, an anticancer effect, and enhancement of sexual performance. It was previously demonstrated that cordycepin could simultaneously activate steroidogenesis and apoptosis in MA-10 mouse Leydig tumor cells. However, the mechanism remains elusive. Thus, aim of the present study was to investigate the steroidogenic and apoptotic mechanism of cordycepin in MA-10 cells. MA-10 cells were treated with cordycepin at various dosages and time courses plus different protein kinase inhibitors. Steroid production, protein expression, and cell viability were then determined. Results illustrated that cordycepin stimulated MA-10 cell steroidogenesis in dose- and time-dependent relationships. However, cordycepin could not induce steroidogenic acute regulatory (StAR) protein expression. However, cordycepin did activate the phospholipase C/protein kinase C (PLC/PKC), but not PKA and PI3K, pathway to induce MA-10 cell steroidogenesis. Moreover, cordycepin could stimulate the phosphorylation of PKC, extracellular signal-regulated kinase 1/2 (ERK1/2), and c-Jun N-terminal kinase (c-JNK), but not p38, in MA-10 cells. In addition, cordycepin could activate the PKC pathway to induce MA-10 cell death, and this death effect was not caused by cordycepin-stimulated progesterone from MA-10 cells. In conclusion, cordycepin stimulated intracellular PLC/PKC and MAPK signal transduction pathways to induce steroidogenesis and cell death in MA-10 mouse Leydig tumor cells.

Icariin induces apoptosis in mouse MLTC-10 Leydig tumor cells through activation of the mitochondrial pathway and down-regulation of the expression of piwil4.

The Leydig cell tumor, derived from interstitial cells, is a rare neoplasm. In most cases, Leydig cell tumors are benign, however, if the tumor is malignant, no effective treatments are currently available. In this study, we aimed to evaluate the effects of icariin on the growth of the mouse Leydig tumor cell line MLTC-1 and to examine its underlying mechanism. Icariin caused a dose-dependent decrease in the viability of MLTC-1 cells, which coincided with an increase in cell apoptosis through regulation of the expression of Bcl-2/Bax and cytochrome c, activation of caspase-9 and -3. Moreover, the pro-apoptotic effect of icariin on MLTC-1 cells is related to piwil4, since icariin induced a decrease in piwil4 protein expression and piwil4 silencing significantly enhanced the cytotoxic effects of icariin in MLTC-1 cells. These findings suggest a novel anticancer effect of icariin in Leydig cell tumor through activation of the mitochondrial pathway and down-regulation of the expression of piwil4.

Proliferative and anti-proliferative effects of retinoic acid at doses similar to endogenous levels in Leydig MLTC-1/R2C/TM-3 cells.

BACKGROUND: Vitamin A is suggested to be protective against oxidative stress. However, different authors observed pro-oxidant effects of retinoids both in experimental works and clinical trials. These discordances are the bases for the investigation of the proliferative and anti-proliferative properties of retinoic acid (RA) in biological systems. METHODS: Cell viability is determined with the MTT assay. Oxidative stress parameters are detected measuring catalase (CAT) and glutathione S-transferase (GST) enzymatic activities. FABP5 mRNA levels are measured by RT-PCR. Autophagy and apoptosis are analyzed by Monodansylcadaverine (MDC) staining and TUNEL assay, respectively. RESULTS AND CONCLUSIONS: RA, at nutraceutic/endogenous doses (10-200 nM), increases cell viability of testes tumor Leydig cell lines (MLTC-1 and R2C) and modulates antioxidant enzyme activities, as CAT and GST. RA is able to induce proliferation through non-classical and redox-dependent mechanisms accompanied by increased levels of FABP5 mRNA. The redox environment of the cell is currently thought to be extremely important for controlling either apoptosis or autophagy. Apoptosis occurs at pharmacological doses, while autophagy, which plays a critical role in removing damaged or surplus organelles in order to maintain cellular homeostasis, is triggered at the critical concentration of 500 nM RA, both in normal and tumoral cells. Slight variations of RA concentrations are evaluated as a threshold value to distinguish between the proliferative or anti-proliferative effects. GENERAL SIGNIFICANCE: Although retinoids have a promising role as antineoplastic agents, physiological levels of RA play a key role in Leydig cancer progression, fostering proliferation and growth of testicular tumoral mass.

Leydig-cell-tumor of the ovary that responded to GnRH-analogue administration - case report and review of the literature.

Progressive hirsutism can be a symptom of an androgen-producing tumor, especially in postmenopausal women. We report a case of a 58-year-old woman who complained of progressive hirsutism, nervousness, irritability, anxiousness and an increased libido. Examination showed an unusual redness of her head, décolleté, palms and soles of her feet. Basal laboratory tests revealed a profound elevation of testosterone levels (7.5 microg/l) and normal levels of androstendione, dehydroepiandrosterone-sulfate, 17alpha-hydroxy-progesterone and thyroid-stimulating hormone. Also remarkable was that her red blood count, hemoglobin and hematocrit values were elevated while erythropoietin was within normal limits. Functional laboratory tests ruled out heterozygous C21-hydroxylase deficiency and showed a moderate insulin resistance on the oral glucose tolerance test. Transvaginal ultrasound revealed a slightly hyperdensic area of 6 mm in the left ovary. Magnetic resonance imaging showed a contrast medium-accumulating area of 2 cm in the left ovary. Since the patient was initially reluctant to undergo surgery, a GnRH-analogue (triptoreline) was administered VIA intramuscular injection once per month for two months and testosterone levels were lowered to less than one third of the initial level (2 microg/l). Surgery was eventually performed with laparoscopic bilateral salpingoophorectomy, hysteroscopy and uterine curettage. The histologic examination revealed a Leydig cell tumor in the hilus and stroma of the left ovary. Postoperatively testosterone levels dropped dramatically and instantly into the normal range. Within months, the red blood count and hematocrit levels were within normal limits. The patient's face became more feminine, the redness of her face and hirsutism regressed. Her anxiousness and nervosity resolved and the insulin sensitivity improved. In this paper, polyglobulia, the metabolic and psychological changes due to hyperandrogenism are discussed, as well as the phenomenon that the tumor responded to a GnRH-analogue. Such a response implies that the tumor is either under gonadotropin control or that GnRH analogues have direct effects via receptors on tumorous Leydig cells.

Recurrent malignant Leydig cell tumor of testis: a case report with review of literature.

Malignant Testicular Leydig Cell tumors (leydigomas) are extremely rare to occur and mostly carry a bad prognosis. Here we describe the disease course of a middle aged patient with recurrent / metastatic Leydig cell tumor of testes, who needed repeated oncosurgical intervention and chemotherapy.

Tumores testiculares bilaterais por hiperplasia congênita de restos adrenais / Bilateral testicular tumors caused by congenital adrenal rest hyperplasia

OBJETIVOS: Tumores testiculares são uma rara condição associada à hiperplasia adrenal congênita (HAC) que decorrem da hiperplasia de restos adrenais intratesticulares (HRA), raramente ocorrendo associados a neoplasias malignas. Sua diferenciação histológica com tumores de células de Leydig é muito difícil, podendo levar a orquiectomias desnecessárias. O objetivo deste relato foi apresentar esse dilema diagnóstico em um paciente com HAC e tumores testiculares bilaterais. MÉTODOS: Relatou-se o caso de um paciente masculino, 16 anos, com diagnóstico de HAC desde os 3 anos de idade, que apresentava tumorações testiculares endurecidas, indolores e de crescimento lento, sendo encaminhado para orquiectomia bilateral. RESULTADOS: Foi decidido por tratamento conservador com prednisona, havendo significativa diminuição do volume testicular e normalização dos níveis de andrógenos. CONCLUSÃO: Este caso demonstra a importância de sempre se considerar a hipótese de HRA intratesticulares no diagnóstico diferencial dos tumores testiculares. A investigação e a conduta devem ser conduzidas de maneira cautelosa para se evitar orquiectomias desnecessárias.

OBJECTIVES: Testicular tumors are a rare condition associated with congenital adrenal hyperplasia (CAH), originated from intratesticular adrenal rest tumors, and they are rarely associated with malignant tumors. Their histological differentiation from Leydig-cell tumors is quite difficult, which would lead to inappropriate orchiectomies. Thus the objective of this report was to present this diagnostic dilemma. METHODS: Reported the case of 16-yr-old boy with previous diagnosis of CAH with bilateral testicular enlargement who was recommended to be submitted to a bilateral orchiectomy. RESULTS: Considering this findings, it was decided to treat conventionally with prednisone with significant reduction of testicular volume, and normalization of androgens levels. CONCLUSION: This case shows the importance of intratesticular adrenal rest tumors in the differential diagnosis of testicular tumors. Cautious approach during investigation and treatment are recommended to avoid inappropriate orchiectomies.