Gonadal Function of Patients Treated With Cisplatin Based Chemotherapy for Germ Cell Cancer

The Effects of Glutathione on Clinically Essential Fertility Parameters in a Bleomycin Etoposide Cisplatin Chemotherapy Model

Chemotherapeutic agents used in the treatment of testicular cancer cause damage to healthy tissues, including the testis. We investigated the effects of glutathione on sperm DNA integrity and testicular histomorphology in bleomycin etoposide cisplatin (BEP) treated rats. Twelve-week-old male rats of reproductive age (n = 24) were randomly divided into three groups, the (i) control group, (ii) BEP group, and (iii) BEP+ glutathione group. Weight gain increase and testes indices of the control group were found to be higher than that of the BEP group and BEP+ glutathione group. While the BEP treatment increased sperm DNA fragmentation and morphological abnormalities when compared to the control group, GSH treatment resulted in a marked decrease for both parameters. Moreover, BEP treatment significantly decreased serum testosterone levels and sperm counts in comparison to the control group, yet this reduction was recovered in the BEP+ glutathione treated group. Similarly, seminiferous tubule epithelial thicknesses and Johnsen scores in testicles were higher in the control and BEP+ glutathione groups than in the BEP-treated group. In conclusion, exogenous glutathione might prevent the deterioration of male reproductive functions by alleviating the detrimental effects of BEP treatment on sperm quality and testicular histomorphology.

OXIDATIVE STRESS AND REPRODUCTIVE FUNCTION: The protection of mammalian spermatozoa against oxidative stress

In brief

This review focuses on the enzymatic antioxidant mechanisms to fight oxidative stress by spermatozoa, highlighting the differences among mammalian species. We discuss recent evidence about players that promote and fight oxidative stress and the need for novel strategies to diagnose and treat cases of male infertility associated with oxidative damage of the spermatozoon.

Abstract

The spermatozoon is very sensitive to high reactive oxygen species (ROS) levels due to its limited antioxidant system. A consortium of antioxidant enzymes, including superoxide dismutase (SOD), glutathione peroxidases (GPXs), peroxiredoxins (PRDXs), thioredoxins, and glutathione-S-transferases, is necessary to produce healthy spermatozoa and to maintain sperm quality to ensure motility, capacitation, and DNA integrity. A delicate balance between ROS production and antioxidant enzymes is needed to ensure ROS-dependent sperm capacitation. GPX4 is an essential component of the mitochondrial sheath in mammalian spermatozoa, and GPX5 is a crucial antioxidant defence in the mouse epididymis to protect the sperm genome during the maturation of the spermatozoon. The mitochondrial superoxide (O2·–) production is controlled by SOD2, and the hydrogen peroxide (H2O2) generated by SOD2 activity and peroxynitrite (ONOO–) are scavenged mainly by PRDXs in human spermatozoa. PRDXs regulate the redox signalling necessary for sperm motility and capacitation, particularly by PRDX6. This enzyme is the first line of defence against oxidative stress to prevent lipid peroxidation and DNA oxidation by scavenging H2O2 and ONOO– through its peroxidase activity and repairing oxidized membranes by its calcium-independent phospholipase A2 activity. The success of antioxidant therapy in treating infertility resides in the proper diagnosis of the presence of oxidative stress and which type of ROS are produced. Thus, more research on the molecular mechanisms affected by oxidative stress, the development of novel diagnostic tools to identify infertile patients with oxidative stress, and randomized controlled trials are of paramount importance to generate personalized antioxidant therapy to restore male fertility.

Peroxiredoxin 6 Peroxidase and Ca2+-Independent Phospholipase A2 Activities Are Essential to Support Male-Mouse Fertility

Human infertility is an important health problem that affects one in six couples worldwide. Half of these cases are due to male infertility. Oxidative stress is a common culprit of male infertility, promoting lipid peroxidation and the oxidation of proteins and DNA in spermatozoa, thereby impairing motility, capacitation and fertilization. Peroxiredoxin 6 (PRDX6) possesses peroxidase and Ca²⁺-independent-phospholipase-A₂ (iPLA₂) activities that scavenge ROS and repair oxidized sperm membranes, respectively. PRDX6 protects spermatozoa against oxidative stress. Infertile men’s spermatozoa have impaired motility, elevated lipid peroxidation levels and DNA damage due to low PRDX6 levels. A lack of PRDX6 is associated with male-mouse infertility. Here, we determined the impact of the absence of PRDX6 peroxidase or iPLA₂ activities on male-mouse fertility. Two-month-old male C57Bl6/J (wild-type), Prdx6^−/−, C47S and D140A knock-in (peroxidase- and iPLA₂-deficient, respectively) male mice were challenged with an in vivo oxidative stress triggered by tert-butyl hydroperoxide (t-BHP). C47S and D140A males produced smaller litters compared to wild-type controls. The t-BHP treatment promoted a lower number of pups, high levels of lipid peroxidation, tyrosine nitration, and DNA oxidation in all mutant spermatozoa compared to wild-type controls. All mutant spermatozoa had impaired capacitation and motility. In summary, both PRDX6 peroxidase and iPLA₂ activities are essential to support male-mouse fertility.

A Novel Combination of γ-Tocopherol-Rich Mixture of Tocopherols and Ascorbic Acid Restores Fertility in Cases of Tyrosine Nitration-Associated Male Infertility in Mice

Infertility is an important health problem that affects up to 16% of couples worldwide. Male infertility is responsible for 50% of the cases. Currently, a physical examination, hormone profiling and the evaluation of two consecutive semen samples (to determine the sperm concentration, motility, morphology and, in very few cases, sperm DNA integrity) are the sole tools that physicians have to evaluate infertility in men. Antioxidant therapy is often used to improve sperm quality and function in infertile men. However, there are controversial results regarding the efficacy of these treatments. Prdx6^-/- male mice are subfertile, displaying significant oxidative damage in the lipids, proteins and DNA of their spermatozoa. Here, we used Prdx6^-/- male mice to test whether a novel combination of tocopherols that contained 60% γ-tocopherol and ascorbic acid could restore their fertility. These mice were fed with the supplemented (Vit. Mix) or control diets. To assess sperm quality, we determined the motility, levels of lipid peroxidation, DNA oxidation and tyrosine nitration in the spermatozoa. The number of pups sired by the Prdx6^-/- mice fed with the Vit. Mix diet was higher than that sired by the males fed with the control diet, and the pups' mortality was lower. The sperm quality was improved in the males fed with the supplemented diet. We concluded that treatment with a supplement composed of tocopherols and rich in γ-tocopherol and ascorbic acid is effective in restoring fertility in cases where oxidative stress and high levels of tyrosine nitration are associated with male infertility.

Reactive Oxygen Species and Male Fertility

Human infertility affects ~15% of couples worldwide, and it is now recognized that in half of these cases, the causes of infertility can be traced to men[...].

Antioxidant Enzymes and Male Fertility: Lessons from Knockout Models

Significance: Spermatozoa are very sensitive to high levels of reactive oxygen species (ROS) due to the limited antioxidant systems present in these terminal cells. However, tight regulation of ROS levels must be ensured to accomplish the unique goal of the spermatozoon, that is, the transfer of the paternal genome into the mature oocyte during the fertilization process. Thus, it is essential that the restricted antioxidant enzymatic systems are active for sperm function. Recent Advances: Oxidative stress is associated with low sperm quality. High levels of ROS in spermatozoa produce oxidation of lipids, proteins, and DNA that lead to lipid peroxidation, oxidation of essential structural proteins and enzymes, and mutations due to oxidation of DNA. Critical Issues: In this study, we described the available knockout mouse models that helped to better understand the role of different antioxidant enzymes in male fertility. We focused mainly on those studies that directly explore the effects of the lack of these enzymes in male fertility and included information when existing knockout mouse models produced for other purposes were used. Special attention was given in this review to the consequences of the absence of antioxidant enzymes on sperm quality and fertility of aging males from the knockout models. Future Directions: Further studies using novel mouse models lacking different antioxidants and their combinations are essential to understand the consequences of high levels of ROS in aging testes, epididymes, spermatozoa, and embryo development to produce a healthy baby.

Long-Term Adverse Effects of Oxidative Stress on Rat Epididymis and Spermatozoa

Oxidative stress is a common culprit of several conditions associated with male fertility. High levels of reactive oxygen species (ROS) promote impairment of sperm quality mainly by decreasing motility and increasing the levels of DNA oxidation. Oxidative stress is a common feature of environmental pollutants, chemotherapy and other chemicals, smoke, toxins, radiation, and diseases that can have negative effects on fertility. Peroxiredoxins (PRDXs) are antioxidant enzymes associated with the protection of mammalian spermatozoa against oxidative stress and the regulation of sperm viability and capacitation. In the present study, we aimed to determine the long-term effects of oxidative stress in the testis, epididymis and spermatozoa using the rat model. Adult male rats were treated with tert-butyl hydroperoxide (t-BHP) or saline (control group), and reproductive organs and spermatozoa were collected at 3, 6, and 9 weeks after the end of treatment. We determined sperm DNA oxidation and motility, and levels of lipid peroxidation and protein expression of antioxidant enzymes in epididymis and testis. We observed that cauda epididymal spermatozoa displayed low motility and high DNA oxidation levels at all times. Lipid peroxidation was higher in caput and cauda epididymis of treated rats at 3 and 6 weeks but was similar to control levels at 9 weeks. PRDX6 was upregulated in the epididymis due to t-BHP; PRDX1 and catalase, although not significant, followed similar trend of increase. Testis of treated rats did not show signs of oxidative stress nor upregulation of antioxidant enzymes. We concluded that t-BHP-dependent oxidative stress promoted long-term changes in the epididymis and maturing spermatozoa that result in the impairment of sperm quality.

Proposed Key Characteristics of Male Reproductive Toxicants as an Approach for Organizing and Evaluating Mechanistic Evidence in Human Health Hazard Assessments

BACKGROUND

Assessing chemicals for their potential to cause male reproductive toxicity involves the evaluation of evidence obtained from experimental, epidemiological, and mechanistic studies. Although mechanistic evidence plays an important role in hazard identification and evidence integration, the process of identifying, screening and analyzing mechanistic studies and outcomes is a challenging exercise due to the diversity of research models and methods and the variety of known and proposed pathways for chemical-induced toxicity. Ten key characteristics of carcinogens provide a valuable tool for organizing and assessing chemical-specific data by potential mechanisms for cancer-causing agents. However, such an approach has not yet been developed for noncancer adverse outcomes.

OBJECTIVES

The objective in this study was to identify a set of key characteristics that are frequently exhibited by exogenous agents that cause male reproductive toxicity and that could be applied for identifying, organizing, and summarizing mechanistic evidence related to this outcome.

DISCUSSION

The identification of eight key characteristics of male reproductive toxicants was based on a survey of known male reproductive toxicants and established mechanisms and pathways of toxicity. The eight key characteristics can provide a basis for the systematic, transparent, and objective organization of mechanistic evidence relevant to chemical-induced effects on the male reproductive system. https://doi.org/10.1289/EHP5045.

Long-Term Follow Up of the Erectile Function of Testicular Cancer Survivors

The diagnosis of testicular cancer (TC) can have a considerable and persistent impact on a patient's sexuality, especially given its location. The high prevalence of TC in young adults, and the good prognosis, explain the great interest in sexual dysfunction and its influence on post-treatment quality of life. The aim of this study was to evaluate the impact of the diagnosis and treatments (inguinal orchiectomy and chemotherapy) on sex life. For this purpose, we recruited 241 TC patients attending the Laboratory of Seminology-Sperm Bank "Loredana Gandini" for sperm cryopreservation (mean age 31.3 ± 6.9 years) and 223 cancer-free healthy men who were undergoing andrological screening (mean age 32.0 ± 7.7 years). The IIEF-15 questionnaire was administered at the baseline (post-orchiectomy, pre-chemotherapy-T0) and at 6 (T1), 12 (T2), 18 (T3), 24 (T4), 48 months (T5) and >5 years (T6, median 96 months) after chemotherapy to all patients, to evaluate the following domains: erectile function (EF), orgasmic function (OF), sexual desire (SD), intercourse satisfaction (IS) and overall satisfaction (OS). A subgroup of patients also underwent blood sex hormone analysis for further correlations with IIEF scores. At the baseline, 37.7% of patients had erectile dysfunction (EF score <26) and all IIEF domains except OF showed significantly lower scores than in controls (p < 0.001). Long-term follow-up revealed persistently lower scores in TC survivors than in controls for EF, SD, IS, and OS. Furthermore, most IIEF domains did not improve significantly in TC patients during the duration of the follow-up, with the exception of EF, which showed a significant improvement from T2. Finally, no significant correlation was found between hormone levels (gonadotropin and testosterone) and IIEF-15 scores. In conclusion, TC and its treatment have a significant effect on sexuality. The absence of a clear correlation with biochemical hypogonadism suggests that this may to a large extent be due to the surgical procedure itself, or to the psychological impact of a cancer diagnosis.

Reactive oxygen species and protein modifications in spermatozoa

Cellular response to reactive oxygen species (ROS) includes both reversible redox signaling and irreversible nonenzymatic reactions which depend on the nature and concentration of the ROS involved. Changes in thiol/disulfide pairs affect protein conformation, enzymatic activity, ligand binding, and protein-protein interactions. During spermatogenesis and epididymal maturation, there are ROS-dependent modifications of the sperm chromatin and flagellar proteins.The spermatozoon is regulated by redox mechanisms to acquire fertilizing ability. For this purpose, controlled amounts of ROS are necessary to assure sperm activation (motility and capacitation). Modifications of the thiol groups redox status of sperm proteins are needed for spermatozoon to achieve fertilizing ability. However, when ROS are produced at high concentrations, the established oxidative stress promotes pathological changes affecting sperm function and leading to infertility. Sperm proteins are sensitive to high levels of ROS and suffer modifications that impact on motility, capacitation, and the ability of the spermatozoon to recognize and bind to the zona pellucida and damage of sperm DNA. Thiol oxidation, tyrosine nitration, and S-glutathionylation are highlighted in this review as significant redox-dependent protein modifications associated with impairment of sperm function and alteration of paternal genome leading to infertility. Peroxiredoxins, the primary antioxidant protection in spermatozoa, are affected by most of the protein modifications described in this review. They play a significant role in both physiological and pathological processes in mammalian spermatozoa.

Deficiency of peroxiredoxin 6 or inhibition of its phospholipase A2 activity impair the in vitro sperm fertilizing competence in mice

Prdx6 -/- male mice are subfertile, and the deficiency or inactivation of Peroxiredoxins (PRDXs) is associated with human male infertility. We elucidate the impact of the lack of PRDX6 or inhibition of its calcium-independent phospholipase A2 (Ca2+-iPLA2) activity by MJ33 on fertilization competence of mouse spermatozoa. Sperm motility, viability, fertilization and blastocyst rates were lower in Prdx6 -/- spermatozoa than in C57BL/6J wild-type (WT) controls (p ≤ 0.05). MJ33 inhibited the PRDX6 Ca2+-iPLA2 activity and reduced these parameters in WT spermatozoa compared with controls (p ≤ 0.05). Levels of lipid peroxidation and of superoxide anion (O2•─) were higher in Prdx6 -/- than in WT spermatozoa (p ≤ 0.05). MJ33 increased the levels of lipid peroxidation and mitochondrial O2•─ production in treated versus non-treated WT spermatozoa. Acrosome reaction, binding to zona pellucida and fusion with the oolemma were lower in Prdx6 -/- capacitated spermatozoa than WT capacitated controls and lower in WT spermatozoa treated with the PRDX6 inhibitor. In conclusion, the inhibition of the PRDX6 Ca2+-iPLA2 activity promotes an oxidative stress affecting viability, motility, and the ability of mouse spermatozoa to fertilize oocytes. Thus, PRDX6 has a critical role in the protection of the mouse spermatozoon against oxidative stress to assure fertilizing competence.

Absence of Peroxiredoxin 6 Amplifies the Effect of Oxidant Stress on Mobility and SCSA/CMA3 Defined Chromatin Quality and Impairs Fertilizing Ability of Mouse Spermatozoa

Oxidative stress, the imbalance between reactive oxygen species production and antioxidant defenses, is associated with male infertility. Peroxiredoxins (PRDXs) are antioxidant enzymes with a wide distribution in spermatozoa. PRDX6 is highly abundant and located in all subcellular compartments of the spermatozoon. Infertile men have lower levels of sperm PRDX6 associated with low sperm motility and high DNA damage. In order to better understand the role of PRDX6 in male reproduction, the aim of this study was to elucidate the impact of the lack of PRDX6 on male mouse fertility. Spermatozoa lacking PRDX6 showed significantly increased levels of cellular oxidative damage evidenced by high levels of lipid peroxidation, 8-hydroxy-deoxyguanosine (DNA oxidation), and protein oxidation (S-glutathionylation and carbonylation), lower sperm chromatin quality (high DNA fragmentation and low DNA compaction, due to low levels of protamination and a high percentage of free thiols), along with decreased sperm motility and impairment of capacitation as compared with wild-type (WT) spermatozoa. These manifestations of damage are exacerbated by tert-butyl hydroperoxide treatment in vivo. While WT males partially recovered the quality of their spermatozoa (in terms of motility and sperm DNA integrity), Prdx6(-/-) males showed higher levels of sperm damage (lower motility and chromatin integrity) 6 mo after the end of treatment. In conclusion, Prdx6(-/-) males are more vulnerable to oxidative stress than WT males, resulting in impairment of sperm quality and ability to fertilize the oocyte, compatible with the subfertility phenotype observed in these knockout mice.

Testicular function among testicular cancer survivors treated with cisplatin-based chemotherapy

Purpose

The aim of our study was to identify the clinical predictors of spermatogenesis recovery in testicular cancer (TC) patients after chemotherapy and to determine the recuperation period for spermatogenesis.

Methods

Patients treated for TC from January 1982 to November 2001 at Chiba University Hospital were retrospectively assessed. Thirty-five patients who met the following criteria were examined-(i) underwent both high orchiectomy and cisplatin-based chemotherapy; (ii) had semen analyses and hormonal measurements; and (iii) were alive with no evidence of disease. Clinical variables associated with normalization of spermatogenesis after chemotherapy were examined. Time to recover normospermia was also evaluated using Kaplan-Meier analysis.

Results

The observation period was 13.3 ± 5.6 years. Reappearance of sperm was confirmed in 85.7 % of patients, and 54.3 % of patients recovered normospermia. Age at diagnosis <25 years (p = 0.0057), number of chemotherapy cycles <4 cycles (p = 0.0042), and follicle-stimulating hormone at the end of chemotherapy <18 mIU/ml (p = 0.0220) were independent factors related to post-chemotherapy normalization of semen findings. The median (95 % CI) time to recover normospermia was 40 (range 22-96) months.

Conclusions

These findings help to predict whether spermatogenesis will recover and its timing. They may also help clinicians identify and manage TC patients at a higher risk of prolonged azoospermia after chemotherapy.

Testosterone deficiency and quality of life in Australasian testicular cancer survivors: a prospective cohort study

This is the first prospective study in a contemporary Australian/New Zealand population to determine the prevalence of testosterone deficiency in testicular cancer survivors at 12 months from treatment, and any association with poorer quality of life. Hormone assays from 54 evaluable patients in a prospective cohort study revealed biochemical hypogonadism in 18 patients (33%) and low-normal testosterone in 13 patients (24%). We found no association between testosterone levels and quality of life (all P > 0.05). Hypogonadal patients should be considered for testosterone replacement to prevent long-term morbidity.

Utilization of sperm banking and barriers to its use in testicular cancer patients

PURPOSE

Testicular cancer is the most common carcinoma in 20- to 40-year-old men. Eighty percent of patients with metastases achieve disease-free status with chemotherapy with or without surgical resection. Standard first-line chemotherapy is bleomycin, etoposide, and cisplatin (BEP) for three to four courses or etoposide and cisplatin (EP) for four courses. Forty percent of patients receiving chemotherapy will have permanently reduced sperm counts impairing future fertility. Sperm banking is an effective method of maintaining fertility. This retrospective study was performed to assess utilization and results from sperm banking, as well as the barriers to its use.

METHODS

Patients 18 and older who had received chemotherapy were given a five-item questionnaire on follow-up visit. This questionnaire included a mix of quantitative and qualitative questions.

RESULTS

Two hundred patients enrolled in the study, and all 200 completed the questionnaire. Of the two hundred, 139 (70 %) patients chose not to bank sperm; 71 (51 %) of those were not interested, 25 (18 %) declined due to desire to start chemotherapy, 24 (17 %) were not offered, 12 (9 %) declined due to cost, and 7 (5 %) answered "other." The average age at cancer diagnosis of patients who banked sperm was 28.4 as opposed to 32.6 for patients who did not (p = 0.003). The percentage of patients that had children before their diagnosis was 21 % in the sperm banking group, and 50 % in the group that did not (p = 0.0002). Sixty-one (30 %) chose to bank sperm; 11 of 61 patients (18 %) utilized the banked sperm; 9 of 11 (82 %) patients that utilized were successful; and 3 of 9 (33 %) successes resulted in multiple gestations.

CONCLUSIONS

Sperm banking provides the opportunity for paternity in testicular cancer patients with reduced sperm counts following treatment. However, the majority of these patients chose not to bank sperm or were not offered the opportunity. A range of factors such as time, emotional state, patient age, disease stage, prior children, institutional practices, and cost all influence whether banking is offered to patients and taken up. The authors provide recommendations to help clinicians overcome some of these barriers.

Ghrelin Prevents Cisplatin-Induced Testicular Damage by Facilitating Repair of DNA Double Strand Breaks Through Activation of p53 in Mice

Cisplatin administration induces DNA damage resulting in germ cell apoptosis and subsequent testicular atrophy. Although 50 percent of male cancer patients receiving cisplatin-based chemotherapy develop long-term secondary infertility, medical treatment to prevent spermatogenic failure after chemotherapy is not available. Under normal conditions, testicular p53 promotes cell cycle arrest, which allows time for DNA repair and reshuffling during meiosis. However, its role in the setting of cisplatin-induced infertility has not been studied. Ghrelin administration ameliorates the spermatogenic failure that follows cisplatin administration in mice, but the mechanisms mediating these effects have not been well established. The aim of the current study was to characterize the mechanisms of ghrelin and p53 action in the testis after cisplatin-induced testicular damage. Here we show that cisplatin induces germ cell damage through inhibition of p53-dependent DNA repair mechanisms involving gamma-H2AX and ataxia telangiectasia mutated protein kinase. As a result, testicular weight and sperm count and motility were decreased with an associated increase in sperm DNA damage. Ghrelin administration prevented these sequelae by restoring the normal expression of gamma-H2AX, ataxia telangiectasia mutated, and p53, which in turn allows repair of DNA double stranded breaks. In conclusion, these findings indicate that ghrelin has the potential to prevent or diminish infertility caused by cisplatin and other chemotherapeutic agents by restoring p53-dependent DNA repair mechanisms.

Oxidative stress impairs function and increases redox protein modifications in human spermatozoa

Oxidative stress, generated by excessive reactive oxygen species (ROS) or decreased antioxidant defenses (and possibly both), is associated with male infertility. Oxidative stress results in redox-dependent protein modifications, such as tyrosine nitration and S-glutathionylation. Normozoospermic sperm samples from healthy individuals were included in this study. Samples were incubated with increasing concentrations (0-5 mM) of exogenous hydrogen peroxide, tert-butyl hydroperoxide, or diethylamine NONOate (DA-NONOate, a nitric oxide (NO∙) donor) added to the medium. Spermatozoa treated with or without ROS were incubated under capacitating conditions and then levels of tyrosine phosphorylation and percentage of acrosome reaction (AR) induced by lysophosphatidylcholine were determined. Modified sperm proteins from cytosolic, triton-soluble, and triton-insoluble fractions were analyzed by SDS-PAGE immunoblotting and immunocytochemistry with anti-glutathione and anti-nitrotyrosine antibodies. Levels of S-glutathionylation increased dose dependently after exposure to hydroperoxides (P<0.05) and were localized mainly to the cytosolic and triton-soluble fractions of the spermatozoa. Levels of tyrosine-nitrated proteins increased dose dependently after exposure to DA-NONOate (P<0.05) and were mainly localized to the triton-insoluble fraction. ROS-treated spermatozoa showed impaired motility without affecting viability (hypo-osmotic swelling test). These treated spermatozoa had tyrosine phosphorylation and AR levels similar to that of non-capacitated spermatozoa following incubation under capacitating conditions, suggesting an impairment of sperm capacitation by oxidative stress. In conclusion, oxidative stress promotes a dose-dependent increase in tyrosine nitration and S-glutathionylation and alters motility and the ability of spermatozoa to undergo capacitation.Free Spanish abstractA Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/149/1/113/suppl/DC1.

Effects of bleomycin, etoposide and cisplatin treatment on Leydig cell structure and transcription of steroidogenic enzymes in rat testis

Cytotoxic anticancer chemotherapy affects pituitary-testicular hormonal axis in humans and in animals. This study investigated the effects on Leydig cells of three cycles of bleomycin, etoposide and cisplatin (0.75, 7.5, and 1.5mg/kg, respectively; BEP) chemotherapy in rat testis. The chemotherapy has induced hyperplasia of and degenerative changes in Leydig cells at the end of BEP exposure, which remained so even after a recovery time of 63 days. The increased testicular oxidative stress at the end of the chemotherapy returned to normal level after the recovery time. The chemotherapy has stimulated the transcription of scavenger receptor class type-B1 (SCARB1), steroidogenic acute-regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage (CYP11A1), CYP17A1, and inhibited that of 17β-hydroxysteroid dehydrogenase (HSD17B6) and CYP19A1 in association with increased cholesterol and decreased testosterone levels. Even after the recovery time, the chemotherapy still had inhibitory effects on the transcription of all of the above genes in addition to luteinizing hormone receptor and HSD3B1, but not on the StAR gene. The cholesterol and testosterone levels also did not show any significant differences with the control group. The decreased testosterone level at the end of chemotherapy was probably due to inhibition of HSD3B1 and HSD17B6 genes. In conclusion, clinically relevant dose-levels and treatment protocols of BEP chemotherapy adversely affect Leydig cell function. The BEP chemotherapy inhibits the transcription of steroidogenic enzymes and that these effects sustain over an extended period of time without returning to normal levels.

The Enzymatic Antioxidant System of Human Spermatozoa

The ejaculated spermatozoon, as an aerobic cell, must fight against toxic levels of reactive oxygen species (ROS) generated by its own metabolism but also by other sources such as abnormal spermatozoa, chemicals and toxicants, or the presence of leukocytes in semen. Mammalian spermatozoa are extremely sensitive to oxidative stress, a condition occurring when there is a net increase in ROS levels within the cell. Opportunely, this specialized cell has a battery of antioxidant enzymes (superoxide dismutase, peroxiredoxins, thioredoxins, thioredoxins reductases, and glutathione s-transferases) working in concert to assure normal sperm function. Any impairment of the antioxidant enzymatic activities will promote severe oxidative damage which is observed as plasma membrane lipid peroxidation, oxidation of structural proteins and enzymes, and oxidation of DNA bases that lead to abnormal sperm function. Altogether, these damages occurring in spermatozoa are associated with male infertility. The present review contains a description of the enzymatic antioxidant system of the human spermatozoon and a reevaluation of the role of its different components and highlights the necessity of sufficient supply of reducing agents (NADPH and reduced glutathione) to guarantee normal sperm function.

Peroxiredoxins: hidden players in the antioxidant defence of human spermatozoa

Spermatozoon is a cell with a precious message to deliver: the paternal DNA. Its motility machinery must be working perfectly and it should be able to acquire fertilizing ability in order to accomplish this mission. Infertility touches 1 in 6 couples worldwide and in half of the cases the causes can be traced to men. A variety of conditions such as infections of the male genital tract, varicocele, drugs, environmental factors, diseases, smoking, etc., are associated with male infertility and a common feature among them is the oxidative stress in semen that occurs when reactive oxygen species (ROS) are produced at high levels and/or when the antioxidant systems are decreased in the seminal plasma and/or spermatozoa. ROS-dependent damage targets proteins, lipids, and DNA, thus compromising sperm function and survival. Elevated ROS in spermatozoa are associated with DNA damage and decreased motility. Paradoxically, ROS, at very low levels, regulate sperm activation for fertilization. Therefore, the regulation of redox signaling in the male reproductive tract is essential for fertility. Peroxiredoxins (PRDXs) play a central role in redox signaling being both antioxidant enzymes and modulators of ROS action and are essential for pathological and physiological events. Recent studies from our lab emphasize the importance of PRDXs in the protection of spermatozoa as infertile men have significant low levels of PRDXs in semen and with little enzymatic activity available for ROS scavenging. The relationships between sperm DNA damage, motility and lipid peroxidation and high levels of thiol-oxidized PRDXs suggest the enhanced susceptibility of spermatozoa to oxidative stress and further support the importance of PRDXs in human sperm physiology. This review aims to characterize PRDXs, hidden players of the sperm antioxidant system and highlight the central role of PRDXs isoforms in the protection against oxidative stress to assure a proper function and DNA integrity of human spermatozoa.

Effects of oncological treatments on semen quality in patients with testicular neoplasia or lymphoproliferative disorders

Pretherapy sperm cryopreservation in young men is currently included in good clinical practice guidelines for cancer patients. The aim of this paper is to outline the effects of different oncological treatments on semen quality in patients with testicular neoplasia or lymphoproliferative disorders, based on an 8-year experience of the Cryopreservation Centre of a large public hospital. Two hundred and sixty-one patients with testicular neoplasia and 219 patients with lymphoproliferative disorders who underwent chemotherapy and/or radiotherapy and pretherapy semen cryopreservation were evaluated. Sperm and hormonal parameters (follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, inhibin B levels) were assessed prior to and 6, 12, 18, 24 and 36 months after the end of cancer treatment. At the time of sperm collection, baseline FSH level and sperm concentration were impaired to a greater extent in patients with malignant testicular neoplasias than in patients with lymphoproliferative disorders. Toxic effects on spermatogenesis were still evident at 6 and 12 months after the end of cancer therapies, while an improvement of seminal parameters was observed after 18 months. In conclusion, an overall increase in sperm concentration was recorded about 18 months after the end of cancer treatments in the majority of patients, even if it was not possible to predict the evolution of each single case 'a priori'. For this reason, pretherapy semen cryopreservation should be considered in all young cancer patients.

Progressive resistance training and cancer testis (PROTRACT) - efficacy of resistance training on muscle function, morphology and inflammatory profile in testicular cancer patients undergoing chemotherapy: design of a randomized controlled trial

Background

Standard treatment for patients with disseminated germ cell tumors is combination chemotherapy with bleomycin, etoposide and cisplatin (BEP). This treatment is highly effective, but the majority of patients experience severe adverse effects during treatment and are at risk of developing considerable long-term morbidity, including second malignant neoplasms, cardiovascular disease, and pulmonary toxicity. One neglected side effect is the significant muscular fatigue mentioned by many patients with testicular cancer both during and after treatment. Very limited information exists concerning the patho-physiological effects of antineoplastic agents on skeletal muscle. The primary aim of this study is to investigate the effects of BEP-treatment on the skeletal musculature in testicular cancer patients, and to examine whether the expected treatment-induced muscular deterioration can be attenuated or even reversed by high intensity progressive resistance training (HIPRT).

Design/Methods

The PROTRACT study is a randomized controlled trial in 30 testicular cancer patients undergoing three cycles of BEP chemotherapy. Participants will be randomized to either a 9-week HIPRT program (STR) initiated at the onset of treatment, or to standard care (UNT). 15 healthy matched control subjects (CON) will complete the same HIPRT program. All participants will take part in 3 assessment rounds (baseline, 9 wks, 21 wks) including muscle biopsies, maximum muscle strength tests, whole body DXA scan and blood samples. Primary outcome: mean fiber area and fiber type composition measured by histochemical analyses, satellite cells and levels of protein and mRNA expression of intracellular mediators of protein turnover. Secondary outcomes: maximum muscle strength and muscle power measured by maximum voluntary contraction and leg-extensor-power tests, body composition assessed by DXA scan, and systemic inflammation analyzed by circulating inflammatory markers, lipid and glucose metabolism in blood samples. Health related Quality of Life (QoL) will be assessed by validated questionnaires (EORTC QLQ-C30, SF-36).

Discussion

This study investigates the muscular effects of antineoplastic agents in testicular cancer patients, and furthermore evaluates whether HIPRT has a positive influence on side effects related to chemotherapy. A more extensive knowledge of the interaction between cytotoxic-induced physiological impairment and exercise-induced improvement is imperative for the future development of optimal rehabilitation programs for cancer patients.

Trial Registration

Current Controlled Trials ISRCTN32132990.

Sequelae of treatment in long-term survivors of testis cancer

CONTEXT

Testicular cancer patients are often diagnosed at a young age, and because of the advances in the treatment of this disease, the vast majority have a normal life expectancy after therapy. Thus, recognition of the long-term sequelae of treatment (ie, surgery, radiation therapy, and chemotherapy) is particularly important in these patients.

OBJECTIVE

To review the adverse effects and the risk of secondary malignancy in long-term survivors of testicular cancer.

EVIDENCE ACQUISITION

We conducted a Medline search to identify original articles and reviews on the long-term effects of testicular cancer treatment. Although the search included articles from January 1948 to February 2011, the majority of the included articles were published in the last two decades.

EVIDENCE SYNTHESIS

All studies examining the long-term sequelae of treatment in testicular cancer are retrospective in nature, with most classified as cohort, case-control, and/or epidemiologic studies. Given that no standardized method of reporting long-term complications exists, evidence synthesis is limited.

CONCLUSIONS

Recent evidence suggests an increased risk of cardiovascular disease, neurotoxicity, and mild reductions in renal function in survivors of testicular cancer. Treatment of testicular malignancy can also negatively affect gonadal function and fertility and has been shown to result in an increased risk of solid malignancy and leukemia.

Aging and osteoporosis in breast and prostate cancer

As people with cancer survive longer, and as the US population ages, skeletal effects of cancer treatment are becoming more pronounced. This is particularly true for breast and prostate cancer survivors because of the high average age of patients with these malignancies, the propensity of older adults in general toward the development of osteoporosis, and the wide use of therapeutic agents in these cancers that negatively impact bone health. Various therapies used in the treatment and prevention of cancer may cause decreases in bone mineral density and an increased risk of debilitating fracture, even in the absence of bone metastases. Aging is both a baseline risk factor in the development of osteoporosis and bony fracture, as well as a predictor of poor outcome after fracture. A variety of mechanisms may be responsible for the development of bone loss in patients with breast or prostate cancer. Cytotoxic chemotherapy may directly exert long-term toxic effects on bone. Chemotherapy and endocrine therapy can induce hypogonadism, leading to an increased rate of bone loss. The risk of skeletal events in older adults due to cancer therapy should be appreciated by all oncologists, geriatricians, and internists. The following review may serve as a guide to the skeletal side effects of cancer therapy in older adults with breast or prostate cancer, how to screen for treatment-related bone loss, and how to best prevent and/or treat skeletal events.

Anticancer chemotherapeutic agents and testicular dysfunction

The improvement of the survival rates of various cancer patients has resulted in increased focus on the long-term complications of treatment. Most anticancer chemotherapeutic agents are gonadotoxic, and sterility is therefore one of the most common complications for cancer survivors. The degree of gonadal dysfunction induced by anticancer chemotherapeutic agents seems to be drug specific and dose related. Following the development of new chemotherapeutic agents that have high benefit-to-risk ratios, sufficient sperm can be acquired by collection of ejaculated semen after the treatment in relatively many cases, and assisted reproductive techniques enable conceptions with even severe spermatogenesis dysfunction. However, anticancer chemotherapeutic agents have consistently exhibited the potential to induce permanent azoospermia. Cryopreservation of semen, which is currently the only proven successful option for future fertility preservation in male cancer patients, should certainly be recommended before cancer therapy. However, to date, no established effective methods have shown the capability to protect gonadal function from anticancer treatment in prepubertal cancer patients.

Testicular cancer survivorship: research strategies and recommendations

Testicular cancer represents the most curable solid tumor, with a 10-year survival rate of more than 95%. Given the young average age at diagnosis, it is estimated that effective treatment approaches, in particular, platinum-based chemotherapy, have resulted in an average gain of several decades of life. This success, however, is offset by the emergence of considerable long-term morbidity, including second malignant neoplasms, cardiovascular disease, neurotoxicity, nephrotoxicity, pulmonary toxicity, hypogonadism, decreased fertility, and psychosocial problems. Data on underlying genetic or molecular factors that might identify those patients at highest risk for late sequelae are sparse. Genome-wide association studies and other translational molecular approaches now provide opportunities to identify testicular cancer survivors at greatest risk for therapy-related complications to develop evidence-based long-term follow-up guidelines and interventional strategies. We review research priorities identified during an international workshop devoted to testicular cancer survivors. Recommendations include 1) institution of lifelong follow-up of testicular cancer survivors within a large cohort setting to ascertain risks of emerging toxicities and the evolution of known late sequelae, 2) development of comprehensive risk prediction models that include treatment factors and genetic modifiers of late sequelae, 3) elucidation of the effect(s) of decades-long exposure to low serum levels of platinum, 4) assessment of the overall burden of medical and psychosocial morbidity, and 5) the eventual formulation of evidence-based long-term follow-up guidelines and interventions. Just as testicular cancer once served as the paradigm of a curable malignancy, comprehensive follow-up studies of testicular cancer survivors can pioneer new methodologies in survivorship research for all adult-onset cancer.

A molecular evaluation of germ cell death induced by etoposide in pubertal rat testes

Etoposide is widely used in the treatment of patients with testicular cancer. The mechanism underlying apoptosis induction in cancer cells has been studied in different cell types, but it is not known whether the same factors participate in viable germ cells undergoing programmed cell death. Since testicular cancer primarily affects young males, we used pubertal rats (21 days old) as a model to determine different apoptotic parameters after etoposide treatment in healthy testes. We found that one intratesticular injection of etoposide (1.2 microg/testis) induced a significant increase in spermatocytes undergoing apoptosis, along with activation of caspase-9, -8 and -3 after 24 h of treatment. Spermatocyte apoptosis was inhibited when a general caspase inhibitor was added along with etoposide. Etoposide induces a significant stabilization/activation of p53, resulting in an increase level of this protein. The mRNA of Bcl-2 antagonist of cell death (BAD), a pro-apoptotic gene and a transcriptional target of p53, was significantly increased after etoposide treatment. Thus, our results suggest a single injection of etoposide induces apoptosis in healthy pachytene spermatocytes mediated by p53 and caspase activation. These findings will assist the search for new therapies to prevent the deleterious effect of cancer drugs upon normal cells.

Risk factors for post-treatment hypogonadism in testicular cancer patients

OBJECTIVES

Testicular germ-cell cancer (TGCC) patients are at risk of developing hypogonadism but no risk factors have yet been defined.

METHODS

Blood was collected from 143 TGCC patients (after orchidectomy, prior to further therapy (T0) and 6, 12, 24, 36 and 60 months (T6, T12, T24, T36 and T60) after therapy). Biological hypogonadism (BH) was defined as: serum testosterone below 10 nmol/l and/or LH >10 IU/l; odds ratios (ORs) for BH with BH at T0, age, stage of disease, testicular characteristics, and androgen receptor polymorphism as predictors were calculated as well as the OR for developing BH post-treatment (one to two cycles of adjuvant chemotherapy (ACT) versus three to four cycles of higher dose chemotherapy (HCT) versus adjuvant radiotherapy (RT)).

RESULTS

HCT increased the OR for BH at T6 (OR 22, 95% confidence interval (CI) 4.4-118) and T12 (OR 5.8, 95% CI 1.5-22). RT increased the OR at T6 (OR 10, 95% CI 2.1-47) and at T12 (OR 3.9, 95% CI 1.1-14). Microlithiasis predicted BH at T0 (OR 11, 95% CI 1.2-112), T12 (OR 3.9, 95% CI 1.1-13), T24 (OR 3.0, 95% CI 1.0-8.8), T36 (OR 5.4, 95% CI 1.7-17) and T60 (OR 4.4, 95% CI 1.2-16). BH at T0 was a risk for BH at T6 (OR 53, 95% CI 19-145), T12 (OR 125, 95% CI 37-430), T24 (OR 88, 95% CI 26-300) and T36 (OR 121, 95% CI 32-460).

CONCLUSIONS

It is clinically relevant that BH at T0 and testicular microlithiasis were predictive factors for post-treatment BH. HCT and RT gave temporary BH.

Current issues in adolescent and young adult cancer survivorship

BACKGROUND

Overall, the survival rate for cancer patients has continued to improve over the past several decades. However, those aged 15 to 29 years have not experienced the same improvements in survival. This review explores some of the challenges faced by adolescent and young adult (AYA) cancer patients and their survivorship needs.

METHODS

Using the OVID Medline database from 1966 to present, a variety of search terms including "adolescent," "young adult," and "cancer survivorship" were entered. Articles related to those obtained by the search were also collected. Additional data were obtained from the SEER database AYA monograph, the Childhood Cancer Survivorship Study, the Report of the Adolescent and Young Adult Oncology Progress Review Group, and the Long-Term Follow-Up Recommendations of the Children's Oncology Group.

RESULTS

Cancer patients in this age-group are at increased risk for second malignancies, cardiotoxicity, and reproductive difficulties. Few data exist concerning intellectual and other psychosocial issues for this specific patient population.

CONCLUSIONS

More research is needed to develop accurate data on treatment and survivorship for AYA patients. A separate cancer discipline focusing on improving outcomes in treatment and survivorship among AYA patients should be developed in major academic cancer centers.

[Osteoporosis in cancer survivors]

The detection of late sequelae in survivors of cancer has become increasingly important as developments in diagnostic and therapeutic methods have led to a more and long-term survival rates in tumoral patients. Osteoporosis is one of such problem that has been increasingly identified in patients with cancer. Significant bone loss and increased risk of fractures have been described in these patients. Medical problems associated with the malignancy or caused by the oncologic treatment are the main factors involved in bone loss. Therefore, patients at risk for bone loss should be undergo preventive or therapeutic interventions at an early enough stage to prevent fractures.

Infertility and testis cancer

Testicular cancer is the most common solid organ tumor in young men and affects men during their reproductive years. Current therapeutic regimens have significantly improved survival but often adversely impact fertility. Understanding the effects of testicular cancer, the systemic effects of neoplasia, and the effects of treatment protocols, such as radiotherapy, chemotherapy, and retroperitoneal lymph node dissection, is essential to restoring and maintaining fertility in men who have germ cell neoplasms.

Hypogonadism and androgen deficiency symptoms in testicular cancer survivors

OBJECTIVES

To investigate the prevalence of hypogonadism in correlation with androgen deficiency symptoms in testicular cancer survivors.

METHODS

Luteinizing hormone, follicle-stimulating hormone, serum testosterone, dehydroepiandrosterone, and sex hormone binding globulin levels were determined in patients who had undergone treatment for unilateral testicular cancer. Patients with serum testosterone levels less than 3.0 ng/mL were classified as hypogonadal; all other testosterone levels signified eugonadism. Additionally, all patients completed the Aging Males' Symptoms scale: scores of less than 26 indicated no androgen deficiency symptoms and scores greater than 27 indicated symptoms.

RESULTS

According to testosterone level, 18 (26.5%) of 68 patients were hypogonadal and 50 (73.5%) were eugonadal (P = 0.456). According to the Aging Males' Symptoms scale, 23 (33.8%) of the 68 patients had androgen deficiency symptoms and 45 (66.2%) had no symptoms (P = 0.267). The median testosterone level was 3.6 ng/mL in all patients with androgen deficiency symptoms, 2.4 ng/mL in patients with androgen deficiency symptoms who were hypogonadal, and 4.7 ng/mL in those with androgen deficiency symptoms who were eugonadal.

CONCLUSIONS

Testicular cancer survivors are at risk of developing hypogonadism and androgen deficiency symptoms. However, no specific testosterone threshold could be detected at which symptoms start, indicating that each patient has an individual testosterone threshold for androgen deficiency symptoms.

Fertility, gonadal and sexual function in survivors of testicular cancer

Modern treatments cure most testicular cancer patients, so an important goal is to minimise toxicity. Fertility and sexual functioning are key issues for patients. We have evaluated these outcomes in a cross-sectional study of long-term survivors of testicular cancer. In total, 680 patients treated between 1982 and 1992 completed the EORTC Qly-C-30(qc30) questionnaire, the associated testicular cancer specific module and a general health and fertility questionnaire. Patients have been subdivided according to treatment received: orchidectomy either alone (surveillance, S n=169), with chemotherapy (C, n=272), radiotherapy (R, n=158), or both chemotherapy and radiotherapy (C/RT n=81). In the surveillance group, 6% of patients had an elevated LH, 41% an elevated FSH and 11% a low (<10 nmol l⁻¹) testosterone. Hormonal function deteriorated with additional treatment, but the effect in general was small. Low testosterone was more common in the C/RT group (37% P=0.006), FSH abnormalities were more common after chemotherapy (C 49%, C/RT 71% both P<0.005) and LH abnormalities after radiotherapy (11% P<0.01) and chemotherapy (10%, P<0.001). Baseline hormone data were available for 367 patients. After treatment, compared to baseline, patients receiving chemotherapy had significantly greater elevations of FSH (median rise of 6 (IQR 3–9.25) iu l⁻¹ compared to 3 (IQR 1–5) iu l⁻¹ for S; P<0.001) and a fall (compared to a rise in the surveillance group) in median testosterone levels (−2 (IQR −8.0 to −1.5) vs 1.0. (IQR −4.0–4.0) P<0.001). Patients with low testosterone (but not elevated FSH) had lower quality of life scores related to sexual functioning on the testicular cancer specific module and lower physical, social and role functioning on the EORTC Qly C-30. Patients with a low testosterone also had higher body mass index and blood pressure. Treatment was associated with reduction in sexual activity and patients receiving chemotherapy had more concerns about fathering children. In total, 207 (30%) patients reported attempting conception of whom 159 (77%) were successful and a further 10 patients were successful after infertility treatment with an overall success rate of 82%. There was a lower overall success rate after chemotherapy (C 71%; CRT 67% compared to S 85% (P=0.028)). Elevated FSH levels were associated with reduced fertility (normal FSH 91% vs elevated 68% P<0.001). In summary, gonadal dysfunction is common in patients with a history of testicular cancer even when managed by orchidectomy alone. Treatment with chemotherapy in particular can result in additional impairment. Gonadal dysfunction reduces quality of life and has an adverse effect on patient health. Most patients retain their fertility, but the risk of infertility is likely to be increased by chemotherapy. Screening for gonadal dysfunction should be considered in the follow-up of testicular cancer survivors.

Treatment of testicular cancer: Influence on pituitary-gonadal axis and sexual function

OBJECTIVES

To investigate the influence of treatment for testicular cancer on the pituitary-gonadal axis and sexual function in long-time survivors after unilateral orchiectomy.

METHODS

Blood was drawn from patients treated for testicular cancer during routine oncologic follow-up for measurement of luteinizing hormone, follicle-stimulating hormone, sexual hormone-binding globulin, testosterone, and bioavailable testosterone. Sexual function was evaluated using the International Index of Erectile Function 15-item (IIEF-15) questionnaire. Patients were grouped according to treatment: group 1 followed a surveillance strategy, group 2 received two cycles of carboplatin monotherapy, and group 3 underwent cisplatin, etoposide, and bleomycin chemotherapy.

RESULTS

No statistically significant difference was found in the serum hormonal levels among the three groups, and all hormonal levels were within the 95% confidence range, except for follicle-stimulating hormone. The median serum testosterone level was 3.5 ng/mL in group 1, 3.9 ng/mL in group 2, and 4.2 ng/mL in group 3. In group 1, the median IIEF-15 score was 64.0, and the median Erectile Function (EF) domain score was 28. The median scores in groups 2 and 3 were 62.5 for IIEF-15 and 27.5 for EF and 65.0 for IIEF-15 and 30.0 for EF, respectively. No correlation was found between testosterone level and IIEF-15 or EF score.

CONCLUSIONS

None of the treatments investigated had a significant influence on the serum hormonal levels in long-time survivors of testicular cancer. Patients undergoing chemotherapy have no greater risk of developing a hormonal disorder than those following a surveillance strategy, and therapy for testicular cancer is not a risk factor for erectile dysfunction.