Benign Leydig cell tumor of the testis associated with human papillomavirus type 33 presenting with the sign of Leser-Trélat

Both selenium deficiency and excess impair male reproductive system via inducing oxidative stress-activated PI3K/AKT-mediated apoptosis and cell proliferation signaling in testis of mice

Selenium (Se) deficiency or excess impairs testicular development and spermatogenesis, while the underlying mechanisms in this regard remain unclear. This study was designed to explore the molecular biology of Se deficiency or excess in spermatogenesis in mice. Three-week-old male mice (n = 10 mice/diet) were fed with Se-deficient diet (SeD, 0.02 mg Se/kg), adequate-Se diet (SeA, 0.2 mg Se/kg), or excess-Se diet (SeE, 2.0 mg Se/kg) for 5 months. Compared with SeA, SeD reduced (P < 0.05) the body weight (10.4%) and sperm density (84.3%) but increased (P < 0.05) sperm deformity (32.8%); SeE decreased (P < 0.05) the sperm density (78.5%) and sperm motility (35.9%) of the mice. Meanwhile, both SeD and SeE increased (P < 0.05) serum FSH concentrations (10.4-25.6%) and induced testicular damage in mice in comparison with the SeA. Compared with SeA, SeD increased (P < 0.05) the 8-OHdG concentration by 25.5%; SeE increased (P < 0.05) both MDA and 8-OHdG concentrations by 118.8-180.3% in testis. Furthermore, transcriptome analysis showed that there 1325 and 858 transcripts were altered (P < 0.05) in the testis by SeD and SeE, respectively, compared with SeA. KEGG pathway analysis revealed that these differentially expressed genes were mainly enriched in the PI3K-AKT signaling pathway, which is regulated by oxidative stress. Moreover, western blotting analysis revealed that SeD and SeE dysregulated PI3K-AKT-mediated apoptosis and cell proliferation signaling, including upregulating (P < 0.05) caspase 3, cleaved-caspase 3, BCL-2 and (or) P53 and downregulating (P < 0.05) PI3K, p-AKT, p-mTOR, 4E-BP1, p-4E-BP1 and (or) p-p70S6K in the testis of mice compared with SeA. Additionally, compared with SeA, both SeD and SeE increased (P < 0.05) GPX3 and SELENOO; SeD decreased (P < 0.05) GPX1, TXRND3 and SELENOW, but SeE increased (P < 0.05) production of three selenoproteins in the testis. Conclusively, both Se deficiency and excess impairs male reproductive system in mice, potentially with the induction of oxidative stress and activation of PI3K/AKT-mediated apoptosis and cell proliferation signaling in the testis.

Altered LKB1/AMPK/TSC1/TSC2/mTOR signaling causes disruption of Sertoli cell polarity and spermatogenesis

Male patients with Peutz-Jeghers syndrome (PJS) have defective spermatogenesis and are at increased risk of developing Sertoli cell tumors. Mutations in the Liver Kinase B1 (LKB1/STK11) gene are associated with the pathogenesis of PJS and have been identified in non-PJS patients with sporadic testicular cancers. The mechanisms controlled by LKB1 signaling in Sertoli cell functions and testicular biology have not been described. We have conditionally deleted the Lkb1 gene (Lkb1(cko)) in somatic testicular cells to define the molecular mechanisms involved in the development of the testicular phenotype observed in PJS patients. Focal vacuolization in some of the seminiferous tubules was observed in 4-week-old mutant testes but germ cell development appeared to be normal. However, similar to PJS patients, we observed progressive germ cell loss and Sertoli cell only tubules in Lkb1(cko) testes from mice older than 10 weeks, accompanied by defects in Sertoli cell polarity and testicular junctional complexes and decreased activation of the MAP/microtubule affinity regulating and focal adhesion kinases. Suppression of AMP kinase and activation of mammalian target of rapamycin (mTOR) signaling were also observed in Lkb1(cko) testes. Loss of Tsc1 or Tsc2 copies the progressive Lkb1(cko) phenotype, suggesting that dysregulated activation of mTOR contributes to the pathogenesis of the Lkb1(cko) testicular phenotype. Pten(cko) mice had a normal testicular phenotype, which could be explained by the comparative lack of mTOR activation detected. These studies describe the importance of LKB1 signaling in testicular biology and the possible molecular mechanisms driving the pathogenesis of the testicular defects observed in PJS patients.

Penile, urethral, and seminal sampling for diagnosis of human papillomavirus infection in men

Methods that used specimens from three genital sites (penile brushing [PB], urethral brushing [UB], and the retrieval of semen [SE]) from 50 men were examined for human papillomavirus (HPV) DNA detection. The rates of detection by PB, UB, SE, PB and UB, and PB and SE were 88.9%, 50.0%, 33.3%, 100%, and 97.2%, respectively. The use of PB and UB appears to be the most accurate method; as an alternative to UB, the use of SE with PB could be used to improve the rate of HPV DNA detection in men.

Presence of human papillomavirus DNA in testicular biopsies from nonobstructive azoospermic men

CONTEXT

Human papillomavirus (HPV) plays a major role in the etiology of many malignancies of diverse localization, such as uterine cervical carcinoma and its precursors. Human papillomavirus sequences have been detected throughout the male lower genitourinary tract, but the role of men as transmitters remains unclear.

OBJECTIVE

To investigate the relationship between azoospermia and the presence of HPV DNA in testicular cells.

DESIGN

One hundred eighty-five patients with azoospermia undergoing testicular biopsy were studied. Histologic study was done on formalin-fixed, paraffin-embedded samples from testicular biopsies, stained with hematoxylin-eosin. Molecular study to detect HPV sequences was performed on genomic DNA isolated from paraffin sections by standard protocols. Seven cases containing HPV sequences were studied after microdissection with PALM microlaser technology in order to determine the presence of HPV DNA sequences in different cells, as well as from seminal tubules or stromal (Leydig) cells.

RESULTS

Human papillomavirus DNA sequences were detected in testicular biopsies of 12 patients (6.48%). Human papillomavirus type 16 was the most common genotype encountered. Among the 92 patients who underwent bilateral testicular biopsy, HPV sequences were detected in 9 patients (9.78%), all of whom showed only unilateral testicular affection, more often in the left testicle (ratio, 2: 1). After microdissection, HPV DNA sequences were seen in Leydig and Sertoli cells; the presence of HPV in germinal cells could not be ruled out.

CONCLUSIONS

Leydig cells, Sertoli cells, and probably germinal cells (cases 2, 3, and 4) harbored HPV DNA sequences. Such findings have not been previously described in testicular tissue.

Sign of Leser-Trélat

The sign of Leser-Trélat is rare. It is defined as the sudden eruption of multiple seborrheic keratoses caused by a malignancy. Because both seborrheic keratoses and cancer are common in the elderly, it is not always easy to tell from the literature or in any given patient if this sign is present. In fact, its validity has been questioned. Its association with malignant acanthosis nigricans is one of several of its features that support its legitimacy as a true paraneoplastic disorder.

Role of retroperitoneal lymph node dissection in clinical stage I Leydig cell tumours

Leydig Cell Tumours (LCT) account for 3% of all testicular tumours; 10% are malignant and are refractory to radio- and chemotherapy. The role of Retroperitoneal Lymph Node Dissection in clinical stage I LCT is therefore a particularly debated one. From March ‘83 to December ‘95, 10 patients with LCT were subjected to orchiectomy (1 of them bilaterally because of a metachronous tumour). In 10 out of 11 specimens the following pathological features – a) size larger than 50 mm, b) infiltration of spermatic cord, c) lymphatics and veins, d) capsule, e) necrosis, f) cellular pleomorphism, g) numerous mitoses, h) nuclear atypia – were absent. The only patient in which b) and d) were present was subjected to RPLND. After a follow-up ranging from 17 to 157 months all patients are disease-free. Abstention from RPLND in clinical stage I LCT therefore seems the more rational choice when the above- listed pathologic features are absent.

Establishment and further characterization of a line of transgenic mice showing testicular tumorigenesis at 100% incidence

We have reported production of transgenic mice containing human papillomavirus type 16 (HPV16) E6 and E7 oncogenes in which a characteristic testicular tumor develops at a very high incidence. Three transgenic mice transmitted the transgene to their siblings, in which the same type of tumor developed. In one line, named line 181, this testicular tumor developed in all the 93 males obtained for 10 generations. In most cases, this tumor was detectable bilaterally in the testes 9 to 10 months postdelivery. On cross-matings with other inbred strains, the HPV transgene was dominant in all the genetic backgrounds examined. In the condition of experimental cryptorchidism, obvious delay of tumor formation was observed. In these testes, the tumor cells were seen to arise from the interstitium. Moreover, this tumor also manifested obvious expression of gonadal specific 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and other enzymes for androgen metabolism. These observations strongly suggest that this tumor has originated from Leydig cells. This transgenic mouse line, therefore, provides a novel system for investigating in vivo carcinogenesis and the mechanism of transformation of male gonadal cells.