Reduced male fertility in childhood cancer survivors

Small pituitary volume and central nervous system anomalies in Fanconi Anemia

Introduction

Fanconi anemia (FA) is a genomic instability disorder associated with congenital abnormalities, including short stature and the presence of central nervous system anomalies, especially in the hypothalamic-pituitary area. Thus, differences in pituitary size could associate with the short stature observed in these patients. Our aim was to evaluate whether central nervous system abnormalities and pituitary gland volume correlate with height and hormone deficiencies in these patients.

Methods

In this cross-sectional exploratory study 21 patients diagnosed with FA between 2017 and 2022 in a Spanish Reference Center were investigated. Magnetic resonance imaging (MRI) was performed and pituitary volume calculated and corelated with height and other endocrine parameters.

Results

The percentage of abnormalities in our series was 81%, with a small pituitary (pituitary volume less than 1 SD) being the most frequent, followed by Chiari malformation type 1. The median value of pituitary volume was -1.03 SD (IQR: -1.56, -0.36). Short stature was found in 66.7% [CI95% 43-85.4]. Total volume (mm3) increases significantly with age and in pubertal stages. There were no differences between volume SD and pubertal stage, or the presence of endocrine deficiencies. No correlations were found between pituitary volume and the presence of short stature. The intraclass correlation index (ICC) average for volume was 0.85 [CI95% 0.61-0.94] indicating a good-to-excellent correlation of measurements.

Discussion

Central nervous system anomalies are part of the FA phenotype, the most frequent after pituitary hypoplasia being posterior fossa abnormalities, which may have clinical repercussions in the patient. It is therefore necessary to identify those who could be candidates for neurosurgical intervention. The size of the pituitary gland is smaller in these patients, but this does not seem to be related to hormone deficiency and short stature or exposure to a low dose of total body irradiation.

Anticancer Drugs-Related Hypogonadism in Male Patients with Advanced Cancers on Active Treatment: A Systematic Review

BACKGROUND

In male patients with cancer treated with antineoplastic drug, hypogonadism is a neglected cause of diminished quality of life. This condition may be cancer related as well as toxicity related. The role of antineoplastic drug in causing hypogonadism is poorly understood. The aim of this systematic review was to establish the prevalence, nature (primary/secondary), and impact of hypogonadism on quality of life in male patients with cancer on antineoplastic therapy.

METHODS

The search strategy used PubMed, Embase, and Cochrane databases to select articles in English language that described hypogonadism in male patients with cancer. The search period was from January 1, 1945 to February 28, 2023. We included observational studies, case reports or case series and excluded studies concerning hematological malignancies, prostate cancer, female patients, and survivors.

FINDINGS

Of 4488 records identified, 28 studies met inclusion criteria (17 observational studies, 11 case reports or case series). Anti-angiogenic drugs and crizotinib were found to have a role in the development of hypogonadism. Patients treated with immune checkpoint-inhibitors developed secondary hypogonadism due to immune-related hypophysitis or orchitis. As for active chemotherapy, platinum salts were often associated with hypogonadism, followed by antimetabolites and taxanes. Selected studies were heterogeneous for populations, interventions, and outcomes assessments. Thus, a generalization is difficult. Moreover, the role of concurrent etiologies cannot be excluded in most studies.

CONCLUSION

Our research emphasizes the importance of evaluating the gonadal axis before treatment in patients considered at risk and testing it at regular intervals or in case of clinical suspicion.

The Effects of Silymarin Supplementation on Post-Thawed Human Sperm Functional Parameters

This study investigated the effect of silymarin on human sperm quality during cryopreservation. Samples were collected from 20 normospermic individuals, and each sample was divided into different concentrations of silymarin comprising the following groups: (0, 20, 100, 500, and 1000 μg/mL silymarin). Sperm quality parameters, such as plasma membrane integrity, mitochondrial membrane potential, acrosomal membrane integrity, and caspase 3 were estimated. Silymarin concentrations of 100-500 μg/mL significantly increased motility, plasma membrane integrity, and mitochondrial activity compared with the frozen control group. Acrosomal integrity was increased in the 1000 μg/mL silymarin group. Moreover, 20 and 100 μg/mL concentrations significantly decreased the percentage of caspase 3. The addition of silymarin antioxidant to the frozen medium reduced damage in the sperm after freezing and thawing. This is the first study that showed silymarin can be useful in cryopreservation of human sperm.

Evaluation of oncofertility care in childhood cancer patients: the EU-Horizon 2020 twinning project TREL initiative

Background

The 5-year survival rate of childhood cancer exceeds 80%, however, many survivors develop late effects including infertility. The aim of this study was to evaluate the current status of oncofertility care at Vilnius University Hospital Santaros Klinikos (VULSK) within the framework of the EU-Horizon 2020 TREL project.

Methods

All parents or patients aged 12-17.9 years treated from July 1, 2021 until July 1, 2022 were invited to complete an oncofertility-care-evaluation questionnaire. After completing the questionnaire, patients were triaged to low-risk (LR) or high-risk (HR) of gonadal damage using a risk stratification tool (triage). Data was assessed using descriptive statistics.

Results

Questionnaires were completed by 48 parents and 13 children triaged as 36 (59%) LR and 25 (41%) HR patients. Most HR respondents (21/25, 84%) were not counseled by a fertility specialist. Six boys (4 HR, 2 LR) were counseled, none of the girls was counseled. Three HR boys underwent sperm cryopreservation. Only 17 (27.9%, 9 HR, 8 LR) respondents correctly estimated their risk. All counseled boys (n = 6) agreed the risk for fertility impairment had been mentioned as compared to 49.1% (n = 27) of uncounseled. All counseled respondents agreed they knew enough about fertility (vs. 42%).

Conclusions

Respondents counseled by a fertility specialist were provided more information on fertility than uncounseled. HR patients were not sufficiently counseled by a fertility specialist. Based on the current experience oncofertility care at VULSK will be improved.

Organ-Sparing Surgery for Testicular Germ Cell Tumors: A Current Perspective

Background and Objectives: We aimed to evaluate the oncological and functional outcomes of organ-sparing surgery for testicular germ cell tumors, a procedure that seeks to strike a balance between effective cancer control and organ preservation, in the treatment of testicular tumors. We aimed to discuss the surgical technique and complications, and determine the appropriate candidate selection for this approach. Material and Methods: A comprehensive literature search was conducted to identify relevant studies on organ-sparing surgery for testicular tumors. Various databases, including PubMed, Embase, and Cochrane Library, were used. Studies reporting on surgical techniques, complications, and oncologic and functional outcomes were included for analysis. Results: Current evidence suggests that organ-sparing surgery for testicular germ cell tumors can be considered a safe and efficacious alternative to radical orchiectomy. The procedure is associated with adequate oncological control, as indicated by low recurrence rates and low complication rates. Endocrine testicular function can be preserved in around 80-90% of patients and paternity can be achieved in approximately half of the patients. Candidate selection for this surgery is typically based on the following criteria: pre-surgery normal levels of testosterone and luteinizing hormone, synchronous or metachronous bilateral tumors, tumor in a solitary testis, and tumor size less than 50% of the testis. Conclusions: Organ-sparing surgery for testicular germ cell tumors offers a promising approach that balances oncological control and preservation of testicular function. Further research, including large-scale prospective studies and long-term follow-ups, is warranted to validate the effectiveness and durability of organ-sparing surgery and to identify optimal patient selection criteria.

Sperm DNA methylome abnormalities occur both pre- and post-treatment in men with Hodgkin disease and testicular cancer

BACKGROUND

Combination chemotherapy has contributed to increased survival from Hodgkin disease (HD) and testicular cancer (TC). However, questions concerning the quality of spermatozoa after treatment have arisen. While studies have shown evidence of DNA damage and aneuploidy in spermatozoa years following anticancer treatment, the sperm epigenome has received little attention. Our objectives here were to determine the impact of HD and TC, as well as their treatments, on sperm DNA methylation. Semen samples were collected from community controls (CC) and from men undergoing treatment for HD or TC, both before initiation of chemotherapy and at multiple times post-treatment. Sperm DNA methylation was assessed using genome-wide and locus-specific approaches.

RESULTS

Imprinted gene methylation was not affected in the sperm of HD or TC men, before or after treatment. Prior to treatment, using Illumina HumanMethylation450 BeadChip (450 K) arrays, a subset of 500 probes was able to distinguish sperm samples from TC, HD and CC subjects; differences between groups persisted post-treatment. Comparing altered sperm methylation between HD or TC patients versus CC men, twice as many sites were affected in TC versus HD men; for both groups, the most affected CpGs were hypomethylated. For TC patients, the promoter region of GDF2 contained the largest region of differential methylation. To assess alterations in DNA methylation over time/post-chemotherapy, serial samples from individual patients were compared. With restriction landmark genome scanning and 450 K array analyses, some patients who underwent chemotherapy showed increased alterations in DNA methylation, up to 2 to 3 years post-treatment, when compared to the CC cohort. Similarly, a higher-resolution human sperm-specific assay that includes assessment of environmentally sensitive regions, or "dynamic sites," also demonstrated persistently altered sperm DNA methylation in cancer patients post-treatment and suggested preferential susceptibility of "dynamic" CpG sites.

CONCLUSIONS

Distinct sperm DNA methylation signatures were present pre-treatment in men with HD and TC and may help explain increases in birth defects reported in recent clinical studies. Epigenetic defects in spermatozoa of some cancer survivors were evident even up to 2 years post-treatment. Abnormalities in the sperm epigenome both pre- and post-chemotherapy may contribute to detrimental effects on future reproductive health.

Fertility Preservation for Prepubertal Patients at Risk of Infertility: Present Status and Future Perspectives

The increasing cure rate of cancer has led to a vast population of survivors having to face the late adverse effects of oncological treatments, with fertility impairment being one of the most sensitive issues for patients. Different options to preserve the fertility of adult patients are routinely used in clinical practice. However, fertility preservation strategies for prepubertal patients at risk of infertility are limited to the cryopreservation of immature gonadal tissue. In recent decades, many research efforts have been focused on the future use of cryopreserved gonadal tissue. This review discusses the common status of fertility preservation measures for pediatric patients undergoing gonadotoxic treatment, focusing especially on the challenges that remain to be solved in order to implement this fundamental service.

Postnatal testicular development in Vietnamese pot-bellied pigs

The Vietnamese pot-bellied pig is a breed with high investigation potential. However, at the reproductive level, its testicular characteristics are still unknown, as well as the different stages of its development. Therefore, the objective of this work is to describe the postnatal testicular development of Vietnamese pot-bellied pigs. In this study, we used pigs grouped into the neonatal stage, animals at zero weeks; prepubertal stage, animals at three and eight weeks; pubertal stage, animals at twelve and sixteen weeks; and postpubertal stage animals at twenty, twenty-four, twenty-eight and thirty-two weeks of age. The neonatal stage is characterized by gonocytes at different migration phases. In the prepubertal stage, gonocytes were differentiated into spermatogonia at 3 weeks of age, and the first spermatocytes were observed at 7 weeks of age. Puberty was determined to start at 12 weeks because seminiferous tubules are found with complete spermatogenesis and the highest peaks in positive cell counting of androgen receptors (AR) and proliferating cell nuclear antigen (PCNA) factor that later decreased and further stabilized in the following weeks. In the postpubertal stage, an increase in seminiferous tubule areas was observed. The number of apoptotic cells ranged from low to null at all ages. Testosterone (T) and gonadotropin levels had two important peaks at 3 and 24 weeks. The seminiferous epithelium cycle was found to have 11 stages according to acrosome development. These characteristics of Vietnamese pot-bellied pig testes, which are different from rat testes and more similar to human testicles, make them a viable model to study human male reproductive biology. The postnatal testicular development of pot-bellied pigs is different from the postnatal testicular development of other breeds. Therefore, due to this difference in size and easy manipulation, the Vietnamese pig is an alternative for investigation compared to other pig breeds.

Testicular Function of Childhood Cancer Survivors: Who Is Worse?

Background: A multi-disciplinary approach has led to an improvement in prognosis of childhood cancers. However, in parallel with the increase in survival rate, there is a greater occurrence of long-term toxicity related to antineoplastic treatment. Hypogonadism and infertility are among the most frequent endocrinological sequelae in young adult childhood cancer survivors. The aim of this study was to identify which category of patients, grouped according to diagnosis, therapy, and age at treatment, shows the worst reproductive function in adulthood. Methods: We evaluated morpho-volumetric development of the testis, endocrine function of the hypothalamic–pituitary–gonadal axis, and sperm parameters in 102 young adult childhood cancer survivors. Results: Overall, about one-third of patients showed low total testicular volume, total testosterone (TT) <3.5 ng/mL, and altered sperm count. Hodgkin’s disease, hematopoietic stem cell transplantation, and non-cranial irradiation associated to chemotherapy were risk factors for poor gonadal function. Patients treated in pubertal age showed lower total testicular volume; however, the difference was due to more gonadotoxic treatment performed in older age. Testicular volume was more predictive of spermatogenesis than follicle-stimulating hormone (FSH), while anti-Müllerian hormone (AMH) was not useful in the evaluation of testicular function of male childhood cancer survivors. Conclusions: Pre-pubertal subjects at high risk of future infertility should be candidates for testicular tissue cryopreservation.

Effects of quercetin, sitagliptin alone or in combination in testicular toxicity induced by doxorubicin in rats

Objective

This study aimed to evaluate the effect of quercetin and/or sitagliptin on testicular damage induced by doxorubicin (DOX).

Methodology

Twenty-five male Wistar rats, weighing 240±20 g, were randomly divided into five groups as follows: a negative control group; that was treated with 1 mL of 0.9% sodium chloride; a DOX-treated group received Intraperitoneal (I.P.) DOX injection (3 mg/kg); a group treated with quercetin 80 mg/kg + sitagliptin 10 mg/kg + DOX; a group treated with quercetin 80 mg/kg + DOX; and a group treated with sitagliptin 10 mg/kg+ DOX. All treatment were given orally daily for 21 days with I.P. DOX 3 mg/kg injection for the treatment groups at days 8, 10, 12, 15, 17, and 19. On day 22, blood was collected for analysis of testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glutathione peroxidase (GPx), and total antioxidant capacity (TAOC). The testes were also removed and sent for histopathological examination.

Results

The study revealed that the combination of quercetin with sitagliptin produced a significant increase in testosterone and FSH levels with a non-significant increase in LH level. This combination also non-significantly decreased the level of ALP and LDH and restored the GPx level with enhancing TAOC.

Conclusion

The results suggest quercetin/sitagliptin combination as a promising therapeutic modality for attenuation of DOX-induced testicular toxicity in rats, and the main mechanism involved in such effect could be due to the antioxidant and anti-inflammatory properties of both agents.

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Testicular organoids to study cell-cell interactions in the mammalian testis

BACKGROUND

Over the last ten years, three-dimensional organoid culture has garnered renewed interest, as organoids generated from primary cells or stem cells with cell associations and functions similar to organs in vivo can be a powerful tool to study tissue-specific cell-cell interactions in vitro. Very recently, a few interesting approaches have been put forth for generating testicular organoids for studying the germ cell niche microenvironment.

AIM

To review different model systems that have been employed to study germ cell biology and testicular cell-cell interactions and discuss how the organoid approach can address some of the shortcomings of those systems.

RESULTS AND CONCLUSION

Testicular organoids that bear architectural and functional similarities to their in vivo counterparts are a powerful model system to study cell-cell interactions in the germ cell niche. Organoids enable studying samples in humans and other large animals where in vivo experiments are not possible, allow modeling of testicular disease and malignancies and may provide a platform to design more precise therapeutic interventions.

Three-dimensional testicular organoids as novel in vitro models of testicular biology and toxicology

Organoids are three dimensional structures consisting of multiple cell types that recapitulate the cellular architecture and functionality of native organs. Over the last decade, the advent of organoid research has opened up many avenues for basic and translational studies. Following suit of other disciplines, research groups working in the field of male reproductive biology have started establishing and characterizing testicular organoids. The three-dimensional architectural and functional similarities of organoids to their tissue of origin facilitate study of complex cell interactions, tissue development and establishment of representative, scalable models for drug and toxicity screening. In this review, we discuss the current state of testicular organoid research, their advantages over conventional monolayer culture and their potential applications in the field of reproductive biology and toxicology.

The humanin analogue (HNG) prevents temozolomide-induced male germ cell apoptosis and other adverse effects in severe combined immuno-deficiency (SCID) mice bearing human medulloblastoma

Subfertility is a major concern of long-term cancer survivors at the reproductive age. We have previously demonstrated that a potent humanin analogue, HNG, protected chemotherapy-induced apoptosis in germ cells but not cancer cells in a metastatic melanoma allograft model. In this study, we utilized severe combined immuno-deficiency (SCID) mice bearing human medulloblastoma to study the effect of HNG in Temozolomide (TMZ) induced male germ cell apoptosis and white blood cell (WBC) suppression. Human medulloblastoma DAOY cells were injected subcutaneously into the right flank of male SCID mice. Three weeks later, groups of tumor-bearing mice received one of the following treatments: vehicle, HNG, TMZ, or TMZ + HNG. 24 h after last injection, the tumors weights, complete blood counts, liver and spleen weights, male germ cell apoptosis was assessed. HNG did not affect TMZ's significant anti-tumor action. HNG significantly prevented TMZ-induced germ cell apoptosis and attenuated the suppressed total WBC and granulocyte counts in SCID mice with or without TMZ treatment. HNG also attenuated TMZ-induced body weight loss and decrease of spleen and liver weights. In conclusion, HNG ameliorated TMZ-induced germ cell apoptosis; WBC and granulocytes loss; and decreased body/organ weights without compromising the TMZ's anti-cancer action on medulloblastoma xenografts in SCID mice.

How does chemotherapy treatment damage the prepubertal testis?

Chemotherapy treatment is a mainstay of anticancer regimens, significantly contributing to the recent increase in childhood cancer survival rates. Conventional cancer therapy targets not only malignant but also healthy cells resulting in side effects including infertility. For prepubertal boys, there are currently no fertility preservation strategies in use, although several potential methods are under investigation. Most of the current knowledge in relation to prepubertal gonadotoxicity has been deduced from adult studies; however, the prepubertal testis is relatively quiescent in comparison to the adult. This review provides an overview of research to date in humans and animals describing chemotherapy-induced prepubertal gonadotoxicity, focusing on direct gonadal damage. Testicular damage is dependent upon the agent, dosage, administration schedule and age/pubertal status at time of treatment. The chemotherapy agents investigated so far target the germ cell population activating apoptotic pathways and may also impair Sertoli cell function. Due to use of combined chemotherapy agents for patients, the impact of individual drugs is hard to define, however, use of in vivo and in vitro animal models can overcome this problem. Furthering our understanding of how chemotherapy agents target the prepubertal testis will provide clarity to patients on the gonadotoxicity of different drugs and aid in the development of cytoprotective agents.

High risk of hypogonadism in young male cancer survivors

OBJECTIVE

Cancer and its treatment in childhood and young adulthood can cause hypogonadism, leading to increased risk of long-term morbidity and mortality. The aim of this study was to evaluate the risk of presenting with biochemical signs of hypogonadism in testicular cancer survivors (TCS) and male childhood cancer survivors (CCS) in relation to the type of treatment given.

DESIGN

Case-control study.

PATIENTS

Ninety-two TCS, 125 CCS (mean age 40 and median age 34 years, respectively; mean follow-up time 9.2 and 24 years, respectively) and a corresponding number of age-matched controls.

MEASUREMENTS

Fasting morning blood samples were analysed for total testosterone (TT), follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The odds ratios (OR) for hypogonadism, defined as primary, secondary, compensated or ongoing androgen replacement, were calculated for TCS and CCS and for subgroups defined by diagnosis and treatment.

RESULTS

Hypogonadism was found in 26% of CCS and 36% of TCS, respectively (OR: 2.1, P = .025 and OR = 2.3, P = .021). Among CCS, the OR was further increased in those given testicular irradiation (OR = 28, P = .004). Radiotherapy other than cranial or testicular irradiation plus chemotherapy, or cranial irradiation without chemotherapy, associated also with increased ORs (OR = 3.7, P = .013, and OR = 4.4, P = .038, respectively). Among TCS, those receiving >4 cycles of cisplatin-based chemotherapy had OR = 17, P = .015.

CONCLUSIONS

Biochemical signs of testosterone deficiency are recognized as markers of decreased life expectancy. Thus, the risk of hypogonadism in TCS and CCS should be recognized and emphasizes the need of long-term follow-up for these men.

Assessment of doxorubicin-induced mouse testicular damage by the novel second-harmonic generation microscopy

Microtubules, maintaining a non-linear structure, are suitable for direct observation in living mammalian by second-harmonic imaging microscopy (SHIM) (a new kind of confocal microscopies). Testes constituted by vast seminiferous microtubules (SM), serve as good candidates for visualization by SHIM. This study employs the SHIM and Western-blot (WB) to assess the cellular-molecular levels of doxorubicin (Dox)-induced mouse testicular damage. The SHIM examination was able to clearly identify the integrity of normal architecture of the living mouse testis, namely, the anatomical features of SM, smooth muscle wall of SM, manchette microtubules, exoplasmic microtubules in Sertoli cells and interstitial connective tissue, as well as the destructive feature of SM in Dox-treated mice (n = 6 per group). By day 21 after Dox-treatment, the testicular weight and testicular length were significantly progressively decreased as Dox dosage was stepwise increased, i.e., 0/5/10/15/20 mg/kg/body-weight (BW) (all p<0.0001). The cross-section area of SM was significantly lower in Dox-treated (15 mg/kg-BW) mice than that in controls (p<0.001). The protein expression of vimentin was significantly progressively increased whereas the protein expression of β-tubulin/androgen-receptor was significantly progressively decreased in stepwise increased Dox dosage (all p<0.001). The protein expressions of inflammatory (MMP-9/IL-1β/TNF-α/iNOX), oxidative-stress (NOX-1/NOX-2/NOX-4/oxidized protein), apoptotic (mitochondrial-Bax/cleaved-caspase-3/PARP), fibrotic (Smad3/TGF-ß) mitochondrial/DNA-damaged (cytosolic cytochrome-C/γ-H2AX/ATM/KU70), and cell apoptotic/death (PTEN/p53) biomarkers were significantly higher in Dox-treated (15 mg/kg-BW) group than those in controls (all p<0.001). In conlusion, the dose-dependent Dox-caused mouse testicular damage can be not only detected by WB in molecular level but also clearly identified by SHIM in living mice.

Cancer survivorship care-planning: Practice, research, and policy implications for social work

Increasing numbers of cancer survivors are living longer than 5 years from their diagnosis date. This has resulted in a growing population of cancer survivors, expected to reach 19 million by 2024. Survivors frequently experience late effects caused by cancer and its treatment, reducing survivors' quality of life in multiple domains. Survivorship care-plans may aid the many physical, psychosocial, and financial needs that emerge posttreatment. However, the lack of reimbursement mechanisms, the limited amount of effectiveness research, and minimal guidelines for content and delivery are barriers to the widespread provision of survivorship care-plans. Challenges and opportunities for social work practice, research, and policy are identified and discussed.

The effects of humanin and its analogues on male germ cell apoptosis induced by chemotherapeutic drugs

Human (HN) prevents stress-induced apoptosis in many cells/tissues. In this study we showed that HN ameliorated chemotherapy [cyclophosphamide (CP) and Doxorubicin (DOX)]-induced male germ cell apoptosis both ex vivo in seminiferous tubule cultures and in vivo in the testis. HN acts by several putative mechanisms via binding to: an IL-12 like trimeric membrane receptor; BAX; or insulin-like growth factor binding protein-3 (IGFBP-3, a proapoptotic factor). To understand the mechanisms of HN on male germ cell apoptosis, we studied five HN analogues including: HNG (HN-S14G, a potent agonist), HNG-F6A (no binding to IGFBP-3), HN-S7A (no self-dimerization), HN-C8P (no binding to BAX), and HN-L12A (a HN antagonist) on CP-induced male germ cell apoptosis in mice. CP-induced germ cell apoptosis was inhibited by HN, HNG, HNG-F6A, HN-S7A, and HN-C8P (less effective); but not by HN-L12A. HN-L12A, but not HN-S7A or HN-C8P, blocked the protective effect of HN against CP-induced male germ cell apoptosis. HN, HN-S7A, and HN-C8P restored CP-suppressed STAT3 phosphorylation. These results suggest that HN: (1) decreases DOX (ex vivo) and CP (in vivo) induced male germ cell apoptosis; (2) action is mediated by the membrane receptor/STAT3 with minor contribution by BAX-binding pathway; (3) self-dimerization or binding to IGFBP-3 may not be involved in HN's effect in testis. HN is an important molecule in the regulation of germ cell homeostasis after injury and agonistic analogues may be developed for treating male infertility or protection against chemotherapy side effects.

TRANSITION IN ENDOCRINOLOGY: Hypogonadism in adolescence

Puberty is a remarkable developmental process with the activation of the hypothalamic-pituitary-gonadal axis culminating in reproductive capacity. It is accompanied by cognitive, psychological, emotional, and sociocultural changes. There is wide variation in the timing of pubertal onset, and this process is affected by genetic and environmental influences. Disrupted puberty (delayed or absent) leading to hypogonadism may be caused by congenital or acquired etiologies and can have significant impact on both physical and psychosocial well-being. While adolescence is a time of growing autonomy and independence, it is also a time of vulnerability and thus, the impact of hypogonadism can have lasting effects. This review highlights the various forms of hypogonadism in adolescence and the clinical challenges in differentiating normal variants of puberty from pathological states. In addition, hormonal treatment, concerns regarding fertility, emotional support, and effective transition to adult care are discussed.