Sperm DNA integrity in testicular cancer patients

Testicular Cancer Survivorship and Fertility Preservation

Testicular cancer disproportionally affects men of reproductive age making fertility an important aspect of testicular cancer survivorship. Men with testicular cancer have more semen parameter abnormalities and a higher incidence of infertility compared to the general population. All treatment options for testicular cancer negatively affect fertility with recovery rates varying by treatment. For these reasons, clinicians should offer sperm cryopreservation, ideally before orchiectomy to maximize the possibility of biologic paternity, if desired. Several innovations have positively impacted this space including direct-to-consumer cryopreservation and bench research demonstrating the feasibility of reintroducing testicular cells post-therapy.

Elucidating the Transcriptional States of Spermatogenesis-Joint Analysis of Germline and Supporting Cell, Mice and Human, Normal and Perturbed, Bulk and Single-Cell RNA-Seq

In studying the molecular underpinning of spermatogenesis, we expect to understand the fundamental biological processes better and potentially identify genes that may lead to novel diagnostic and therapeutic strategies toward precision medicine in male infertility. In this review, we emphasized our perspective that the path forward necessitates integrative studies that rely on complementary approaches and types of data. To comprehensively analyze spermatogenesis, this review proposes four axes of integration. First, spanning the analysis of spermatogenesis in the healthy state alongside pathologies. Second, the experimental analysis of model systems (in which we can deploy treatments and perturbations) alongside human data. Third, the phenotype is measured alongside its underlying molecular profiles using known markers augmented with unbiased profiles. Finally, the testicular cells are studied as ecosystems, analyzing the germ cells alongside the states observed in the supporting somatic cells. Recently, the study of spermatogenesis has been advancing using single-cell RNA sequencing, where scientists have uncovered the unique stages of germ cell development in mice, revealing new regulators of spermatogenesis and previously unknown cell subtypes in the testis. An in-depth analysis of meiotic and postmeiotic stages led to the discovery of marker genes for spermatogonia, Sertoli and Leydig cells and further elucidated all the other germline and somatic cells in the testis microenvironment in normal and pathogenic conditions. The outcome of an integrative analysis of spermatogenesis using advanced molecular profiling technologies such as scRNA-seq has already propelled our biological understanding, with additional studies expected to have clinical implications for the study of male fertility. By uncovering new genes and pathways involved in abnormal spermatogenesis, we may gain insights into subfertility or sterility.

Radiotherapy and Testicular Function: A Comprehensive Review of the Radiation-Induced Effects with an Emphasis on Spermatogenesis

This comprehensive review explores the existing literature on the effects of radiotherapy on testicular function, focusing mainly on spermatogenic effects, but also with a brief report on endocrine abnormalities. Data from animal experiments as well as results on humans either from clinical studies or from accidental radiation exposure are included to demonstrate a complete perspective on the level of vulnerability of the testes and their various cellular components to irradiation. Even relatively low doses of radiation, produced either from direct testicular irradiation or more commonly from scattered doses, may often lead to detrimental effects on sperm count and quality. Leydig cells are more radioresistant; however, they can still be influenced by the doses used in clinical practice. The potential resultant fertility complications of cancer radiotherapy should be always discussed with the patient before treatment initiation, and all available and appropriate fertility preservation measures should be taken to ensure the future reproductive potential of the patient. The topic of potential hereditary effects of germ cell irradiation remains a controversial field with ethical implications, requiring future research.

Fertility preservation in adult male patients with cancer: a systematic review and meta-analysis

STUDY QUESTION

Does sperm cryopreservation serve as a feasible and effective method for preserving fertility in adult male patients with cancer?

SUMMARY ANSWER

Sperm cryopreservation is an effective fertility preservation method and may benefit patients with cancer.

WHAT IS KNOWN ALREADY

Sperm cryopreservation is the only way to efficiently preserve male fertility. It is an important procedure in ART. Recently, due to remarkable advances in cancer treatment, an increasing number of studies have reported the outcomes of sperm cryopreservation in patients with cancer.

STUDY DESIGN SIZE DURATION

We conducted an extensive literature search for relevant studies published through to 31 December 2021, in the following databases: CENTRAL, CNKI, Cochrane Systematic Reviews, EMBASE, MEDLINE, PUBMED, and Web of Science. The search terms used were '(cryopreservation OR freeze OR freezing OR banking OR cryostorage OR storage) AND (sperm OR semen OR spermatozoon) AND (cancer OR tumor OR malignancy OR neoplasm)'.

PARTICIPANTS/MATERIALS SETTING METHODS

We included all studies that reported offering or attempting to cryopreserve sperm before or during cancer treatment in male patients considered at risk of treatment-related fertility impairment. We evaluated the eligibility of all data in each study. The major exclusion criteria were as follows: non-cancer patients; pediatric and adolescent cancer patients; not reporting the use of cryopreserved sperm; use of fresh semen for ART; not reporting the number of patients with cancer offered sperm cryopreservation or attempting to do so before or during treatment; using an experimental fertility preservation technique such as preservation of testicular tissue or spermatogonial stem cells; duplicate data; abstracts, case report, comments, reviews, or editorials; insufficient data reported. The quality of the included studies was assessed using the Newcastle-Ottawa scale and the Methodological Index for Non-Randomized Studies.

MAIN RESULTS AND THE ROLE OF CHANCE

This meta-analysis included 69 non-randomized studies, with 32 234 patients referred for sperm analysis and 23 178 patients cryopreserving at least one sperm sample. The pooled failed-to-cryopreserve rate was 10% (95% CI, 8-12%), and the sperm disposal and sperm use rates were 23% (95% CI, 16-30%) and 9% (95% CI, 8-10%), respectively. The pregnancy, miscarriage, and delivery rates were 28% (95% CI, 22-33%), 13% (95% CI, 10-17%), and 20% (95% CI, 15-25%), respectively. Subgroup analysis showed higher pregnancy and delivery rates, as well as a lower failed-to-cryopreserve rate, in recent studies compared to those released a decade ago. The studies from Asia reported higher sperm disposal and pregnancy rates than in other continents. Our analysis showed clinical pregnancy rates per cycle of 34% (27-41%), 24% (14-35%), and 9% (5-15%) and delivery rates per cycle of 23% (17-30%), 18% (11-26%), and 5% (1-9%) for ICSI, IVF, and IUI, respectively.

LIMITATIONS REASONS FOR CAUTION

As with all meta-analyses, some limitations should be considered. The first limitation of our study is that the data span 36 years. During this time, the World Health Organization has revised its sperm analysis standards, and other important changes have been made. There is also a limitation in that the outcome does not analyze the correlation between the type of cancer and sperm quality. Many of the earlier studies were limited by small sample sizes and a lack of control groups. Furthermore, almost all studies did not consider the severity of the disease, which could potentially have a substantial impact on the results. Consequently, further research should evaluate the effect of the type of cancer and, in particular, the severity of the condition on sperm quality in order to draw more precise conclusions. Similarly, it is inappropriate that most studies failed to differentiate between patients with different types of tumors and instead drew generalized conclusions that are presumed to apply to all patients with cancer. In the present analysis, we did not have in-depth information on patients' disease, and although extensive efforts were made to conduct a thorough systematic review and meta-analysis of the outcomes for patients with various types of tumors, the results must be acknowledged as being subject to bias. However, the use of average results obtained in each study, without the patient-level data, might also represent a source of bias.

WIDER IMPLICATIONS OF THE FINDINGS

Sperm cryopreservation is an effective fertility preservation method and may benefit patients with cancer. The observed utilization rate of frozen sperm at 9% may underestimate the actual usage, as the short follow-up period is inadequate for obtaining comprehensive data on the use of frozen sperm in young cancer survivors. ART plays an important role in fertility preservation and the achievement of pregnancy, with this meta-analysis showing that ICSI delivers better clinical outcomes than IVF or IUI in patients with cancer undergoing fertility preservation.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the National Natural Science Foundation of China (grant no. 82001634, 81960550), and the China Postdoctoral Science Foundation (2019M661521). There are no competing interests to declare.

REGISTRATION NUMBER

CRID 42022314460.

Long-term effect of cytotoxic treatments on sperm DNA fragmentation in patients affected by testicular germ cell tumor

INTRODUCTION

Testicular germ cell tumor is the most frequent neoplasia in men of reproductive age, with a 5-year survival rate of 95%. Antineoplastic treatments induce sperm DNA fragmentation, especially within the first year post-therapy. Data in the literature are heterogeneous concerning longer follow-up periods, and the large majority is limited to 2 years.

OBJECTIVE

To define the timing for the recovery of sperm DNA damage and the proportion of patients with severe DNA damage at 2 and 3 years from the end of therapy.

MATERIALS AND METHODS

Sperm DNA fragmentation was evaluated in 115 testicular germ cell tumor patients using terminal deoxynucleotidyl transferase dUTP nick end labeling assay coupled with flow cytometry before (T0 ) and 2 (T2 ) and 3 (T3 ) years post-treatment. Patients were divided based on the type of treatment: carboplatin, bleomycin-etoposide-cisplatin, and radiotherapy. For 24 patients, paired sperm DNA fragmentation data were available at all time-points (T0 -T2 -T3 ). Seventy-nine cancer-free, fertile normozoospermic men served as controls. Severe DNA damage was defined as the 95th percentile in controls (sperm DNA fragmentation = 50%).

RESULTS

Comparing patients versus controls, we observed: (i) no differences at T0 and T3 and (ii) significantly higher sperm DNA fragmentation levels (p < 0.05) at T2 in all treatment groups. Comparing pre- and post-therapy in the 115 patients, the median sperm DNA fragmentation values were higher in all groups at T2 , reaching significance (p < 0.05) only in the carboplatin group. While the median sperm DNA fragmentation values were also higher in the strictly paired cohort at T2 , about 50% of patients returned to baseline. The proportion of severe DNA damage in the entire cohort was 23.4% and 4.8% of patients at T2 and T3 , respectively.

DISCUSSION

Currently, testicular germ cell tumor patients are advised to wait 2 years post-therapy before seeking natural pregnancy. Our results suggest that this period may not be sufficient for all patients.

CONCLUSION

The analysis of sperm DNA fragmentation may represent a useful biomarker for pre-conception counseling following cancer treatment.

Male infertility

Clinical infertility is the inability of a couple to conceive after 12 months of trying. Male factors are estimated to contribute to 30-50% of cases of infertility. Infertility or reduced fertility can result from testicular dysfunction, endocrinopathies, lifestyle factors (such as tobacco and obesity), congenital anatomical factors, gonadotoxic exposures and ageing, among others. The evaluation of male infertility includes detailed history taking, focused physical examination and selective laboratory testing, including semen analysis. Treatments include lifestyle optimization, empirical or targeted medical therapy as well as surgical therapies that lead to measurable improvement in fertility. Although male infertility is recognized as a disease with effects on quality of life for both members of the infertile couple, fewer data exist on specific quantification and impact compared with other health-related conditions.

Sperm DNA Damage and Its Relevance in Fertility Treatment: A Review of Recent Literature and Current Practice Guidelines

Sperm deoxyribonucleic acid (DNA) damage has recently emerged as one of the most controversial topics in male reproductive medicine. While level I evidence indicates that abnormal sperm DNA damage has substantial adverse effects on reproductive outcomes (including chance of pregnancy and risk of miscarriage), there is limited consensus on how sperm DNA fragmentation (SDF) testing should be performed and/or interpreted in clinical practice. In this article, we review: (1) how SDF is assessed, (2) cumulative evidence regarding its impact on reproductive outcomes, (3) methods for mitigating high SDF, and (4) the most recent practice guidelines available for clinicians regarding the use and interpretation of SDF testing.

Microsurgical Management of Male Infertility: Compelling Evidence That Collaboration with Qualified Male Reproductive Urologists Enhances Assisted Reproductive Technology (ART) Outcomes

A male factor plays a significant role in a couple's reproductive success. Today, advances in reproductive technology, such as intracytoplasmic sperm injection (ICSI), have allowed it to be possible for just a single sperm to fertilize an egg, thus, overcoming many of the traditional barriers to male fertility, such as a low sperm count, impaired motility, and abnormal morphology. Given these advances in reproductive technology, it has been questioned whether a reproductive urologist is needed for the evaluation and treatment of infertile and subfertile men. In this review, we aim to provide compelling evidence that collaboration between reproductive endocrinologists and reproductive urologists is essential for optimizing a couple's fertility outcomes, as well as for improving the health of infertile men and providing cost-effective care.

Testicular Dysfunction Among Cancer Survivors

In parallel with increased survival rates, quality of life (QoL) has become of growing importance in the management of young cancer survivors. Several surveys have indicated that in those subjects, the issue of reproductive function is considered as one of the main QoL aspects. In this article, we summarize the current evidence, as well as gaps of knowledge and research needs, regarding the impact of cancer and cancer treatment on testicular function-including fertility and androgen production. Also, pre and posttherapy clinical management of reproductive issues in male cancer survivors, are given.

Fertility preservation in boys facing gonadotoxic cancer therapy

Patient survival following childhood cancer has increased with contemporary radiation and chemotherapy techniques. However, gonadotoxicity associated with treatments means that infertility is a common consequence in survivors. Novel fertility preservation options are emerging, but knowledge about these options amongst urologists and other medical professionals is lacking. Pre-pubertal boys generally do not produce haploid germ cells. Thus, strategies for fertility preservation require cryopreservation of tissue containing spermatogonial stem cells (SSCs). Few centres worldwide routinely offer this option and fertility restoration (including testicular tissue engraftment, autotransplantation of SSCs and in vitro maturation of SSCs to spermatozoa) post-thaw is experimental. In pubertal boys, the main option for fertility preservation is masturbation and cryopreservation of the ejaculate. Assisted ejaculation using penile vibratory stimulation or electroejaculation and surgical sperm retrieval can be used in a sequential manner after failed masturbation. Physicians should inform boys and parents about the gonadotoxic effects of cancer treatment and offer fertility preservation. Preclinical experience has identified challenges in pre-pubertal fertility preservation, but available options are expected to be successful when today's pre-pubertal boys with cancer become adults. By contrast, fertility preservation in pubertal boys is clinically proven and should be offered to all patients undergoing cancer treatment.

Lower female partner live birth rate in male cancer survivors: An age-matched cohort analysis of the Utah Population Database

We determine the time to first live birth for female partners of males after a cancer diagnosis. Our group performed a retrospective, population-based, age-matched cohort study of Utah male residents diagnosed with cancer at age 18 years or later between 1956 and 2013 (exposed) matched to male Utah residents without cancer diagnosis (unexposed). Using stratified Cox proportional hazard models, we adjusted for race, ethnicity and number of live births prior to cancer diagnosis, to estimate the effect of time to a partner live birth following cancer diagnosis. Our study cohort included 19,303 men diagnosed with cancer (exposed) and 93,608 age-matched men without cancer diagnoses (unexposed). Exposed men were less likely to have a live birth prior to first cancer diagnosis (60.7% vs. 65.4%, p < 0.001) and after first cancer diagnosis (10.9% vs. 12.2%, p < 0.001) compared to unexposed men. Exposed men had a fertility hazard rate that was 31% lower after cancer diagnosis date than unexposed men (HR: 0.69; 95% CI: 0.65-0.72). This was most profound for men aged 18-30 years (HR: 0.59, 95% CI: 0.55-0.63). Male cancer survivors have a 31% lower female partner live birth rate after cancer diagnosis. These findings are important for patient counselling regarding fertility preservation at the time of cancer diagnosis.

Sperm DNA fragmentation testing: Summary evidence and clinical practice recommendations

We herein summarise the evidence concerning the impact of sperm DNA fragmentation in various clinical infertility scenarios and the advances on sperm DNA fragmentation tests. The collected evidence was used to formulate 41 recommendations. Of these, 13 recommendations concern technical aspects of sperm DNA fragmentation testing, including pre-analytical information, clinical thresholds and interpretation of results. The remaining 28 recommendations relate to indications for sperm DNA fragmentation testing and clinical management. Clinical scenarios like varicocele, unexplained infertility, idiopathic infertility, recurrent pregnancy loss, intrauterine insemination, in vitro fertilisation/intracytoplasmic sperm injection, fertility counselling for men with infertility risk factors and sperm cryopreservation have been contemplated. The bulk evidence supporting the recommendations has increased in recent years, but it is still of moderate to low quality. This guideline provides clinicians with advice on best practices in sperm DNA fragmentation testing. Also, recommendations are provided on possible management strategies to overcome infertility related to sperm DNA fragmentation, based on the best available evidence. Lastly, we identified gaps in knowledge and opportunities for research and elaborated a list of recommendations to stimulate further investigation.

Oxidative stress in the pathophysiology of male infertility

The effects of reactive oxygen species on male fertility are governed by the oxidative paradox, defined by a delicate balance between oxidative stress and antioxidant capacity. When regulated appropriately, reactive oxygen species ensure effective function; however, when uninhibited, they represent key players in male factor infertility. Mechanisms responsible for this include oxidative destruction of sperm lipid membranes, damage to gamete DNA both by gene mutation and by direct breakdown of the DNA backbone, mitochondrial dysfunction and apoptotic cell death. Utilizing various male pathologies as case studies, we see ways in which oxidative stress has the potential to impact fertility in a negative way. Varicocele, erectile dysfunction, testicular cancer and even idiopathic male infertility highlight common mechanistic pathways, as well as subtle variations in the ways reactive oxygen species can operate. Oxidative biomarkers have emerged to better study male infertility, predict reproductive success and modify assisted reproductive technologies to minimize oxidative stress.

Risk of Congenital Malformations in Children Born Before Paternal Cancer

Background

Increased risk of congenital malformations in children fathered by men treated for cancer might be due to mutagenicity of cancer therapies. Finding of increased malformation prevalence in offspring born before paternal cancer would indicate a treatment-independent mechanism.

Methods

Through national registries, we obtained data on singletons born in Sweden from 1994 to 2014 (n = 1 796 160) and their fathers and mothers (1 092 950/1 092 011). Men with cancer (n = 23 932) fathered 26 601 and 9926 children before and after cancer diagnosis, respectively. Associations between paternal cancer, diagnoses retrieved from the Swedish Cancer Register, and offspring malformations, based on Swedish Medical Birth Register data, were estimated by logistic regression.

Results

Children conceived before paternal cancer had a statistically significantly increased risk of all malformations (odds ratio [OR] = 1.08, 95% confidence interval [CI] = 1.02 to 1.15, P = .016, 3.8% vs 3.4%) and major malformations (OR = 1.09, 95% CI = 1.01 to 1.18, P = .03, 2.4% vs 2.1%). Eye and central nervous system cancers were associated with the highest risk of all malformations (OR = 1.30, 95% CI = 1.04 to 1.61, P = .02, 4.5% vs 3.4%). A similar trend was seen for testicular cancer. The malformation rates among children conceived before and after paternal cancer diagnosis were similar.

Conclusions

The association between paternal cancer and risk of malformations in the offspring is not solely due to mutagenic effects of cancer therapy. The increase in prevalence of birth anomalies among children of fathers with malignancy might be due to cancer per se or a common underlying paternal factor, for example, genomic instability.

Cancer therapy and risk of congenital malformations in children fathered by men treated for testicular germ-cell cancer: A nationwide register study

BACKGROUND

Because of the potential mutagenic effects of chemo- and radiotherapy, there is concern regarding increased risk of congenital malformations (CMs) among children of fathers with cancer. Previous register studies indicate increased CM risk among children conceived after paternal cancer but lack data on oncological treatment. Increased CM risk was recently reported in children born before paternal cancer. This study aims to investigate whether anti-neoplastic treatment for testicular germ-cell cancer (TGCC) implies additional CM risk.

METHODS AND FINDINGS

In this nationwide register study, all singletons born in Sweden 1994-2014 (n = 2,027,997) were included. Paternal TGCC diagnoses (n = 2,380), anti-neoplastic treatment, and offspring CMs were gathered from the Swedish Norwegian Testicular Cancer Group (SWENOTECA) and the Swedish Medical Birth Register. Children were grouped based on +/- paternal TGCC; treatment regimen: surveillance (n = 1,340), chemotherapy (n = 2,533), or radiotherapy (n = 360); and according to time of conception: pre- (n = 2,770) or post-treatment (n = 1,437). Odds ratios (ORs) for CMs were calculated using logistic regression with adjustment for parental ages, maternal body mass index (BMI), and maternal smoking. Children conceived before a specific treatment acted as reference for children conceived after the same treatment. Among children fathered by men with TGCC (n = 4,207), 184 had a CM. The risk of malformations was higher among children of fathers with TGCC compared with children fathered by men without TGCC (OR 1.28, 95% confidence interval [CI] 1.19-1.38, p = 0.001, 4.4% versus 3.5%). However, no additional risk increase was associated with oncological treatment when comparing post-treatment-to pretreatment-conceived children (chemotherapy, OR = 0.82, 95% CI 0.54-1.25, p = 0.37, 4.1% versus 4.6%; radiotherapy, OR = 1.01, 95% CI 0.25-4.12, p = 0.98, 3.2% versus 3.0%). Study limitations include lack of data on use of cryopreserved or donor sperm and on seminoma patients for the period 1995-2000-both tending to decrease the difference between the groups with TGCC and without TGCC. Furthermore, the power of analyses on chemotherapy intensity and radiotherapy was limited.

CONCLUSIONS

No additional increased risk of CMs was observed in children of men with TGCC treated with radio- or chemotherapy. However, paternal TGCC per se was associated with modestly increased risk for offspring malformations. Clinically, this information can reassure concerned patients.

Sperm count in Swedish clinical stage I testicular cancer patients following adjuvant treatment

BACKGROUND

Little is known regarding sperm production following adjuvant treatment in testicular cancer (TC) clinical stage I (CS I) patients.

PATIENTS AND METHODS

A total of 182 TC patients aged 18-50 years were prospectively included during 2001-2006 at any given time within 5 years of orchiectomy. Semen samples were delivered postorchiectomy but before further treatment, 6, 12, 24, 36 and 60 months (T0-T60) after completed therapy. Total sperm number (TSN) and sperm concentration (SC) were used as measurements of testicular function. Four groups according to treatment modality were identified; Radiotherapy; To a total dose of 25.2 Gy to the infradiaphragmal paraaortic and ipsilateral iliac lymph nodes (RT, N = 70), one cycle of adjuvant BEP (bleomycin, etoposide, cisplatin, 5 day regimen) (BEP, N = 62), one cycle of adjuvant carboplatin AUC 7 (Carbo, N = 22), and patients managed by surveillance (SURV, N = 28).

RESULTS

In the cross-sectional analysis, a significant but transient drop in mean TSN and mean SC (T0-T60) was seen at T6 after radiotherapy. Apart from a significant increase in mean SC at T12 compared with baseline, no significant differences were observed in the other treatment groups. In 119 patients delivering 3 or more samples, values in TSN and SC were rather stable over time. Azoospermic patients (N = 11) were observed in most treatment groups except for in the BEP group. During follow-up, one azoospermic patient belonging to the Carbo group became normospermic.

CONCLUSIONS

No clinically significant long-term effect on TSN or SC associated with adjuvant treatment in TC CSI patients was found. However, as patients may have low sperm counts before orchiectomy as well as after adjuvant treatment, we offer sperm banking before orchiectomy as assisted reproductive measures may be necessary regardless of treatment given.

Radiotherapy toxicity

Radiotherapy is used in >50% of patients with cancer, both for curative and palliative purposes. Radiotherapy uses ionizing radiation to target and kill tumour tissue, but normal tissue can also be damaged, leading to toxicity. Modern and precise radiotherapy techniques, such as intensity-modulated radiotherapy, may prevent toxicity, but some patients still experience adverse effects. The physiopathology of toxicity is dependent on many parameters, such as the location of irradiation or the functional status of organs at risk. Knowledge of the mechanisms leads to a more rational approach for controlling radiotherapy toxicity, which may result in improved symptom control and quality of life for patients. This improved quality of life is particularly important in paediatric patients, who may live for many years with the long-term effects of radiotherapy. Notably, signs and symptoms occurring after radiotherapy may not be due to the treatment but to an exacerbation of existing conditions or to the development of new diseases. Although differential diagnosis may be difficult, it has important consequences for patients.

Antioxidant treatment ameliorates germ cell apoptosis induced by a high-dose ionizing irradiation in rats

BACKGROUND

Exposure to ionizing radiation results in cytotoxic and genotoxic effects caused mainly by the oxidative damage. In the present study, we investigated the radioprotective effect of novel antioxidant cocktail on germ cell apoptosis and spermatogenesis in rats subjected to whole body radiation (WBIR).

METHODS

Adult male rats weighing 250-270 g were divided into four groups, eight rats each. Group 1 served as untreated control, group 2 received an IP single dose of antioxidant cocktail (1 ml). Group 3 was exposed to a WBIR (6 Gy). Group 4 received antioxidant cocktail before WBIR. Rats from each group were killed after 48 h. MDA levels were measured in serum (TBARS assay). Johnsen's criteria and the number of germinal cell layers were used to categorize spermatogenesis. TUNEL assay was used to determine germ cell apoptosis. Statistical analysis was performed using one-way ANOVA test.

RESULTS

WBIR resulted in histological testicular damage (decrease in Johnsen's criteria, p < 0.05) that was accompanied by a significant increase in germ cell apoptosis, expressed as the number of apoptotic cells per 100 tubules (AI-1 apoptotic index) and the number of positive tubules per 100 tubules (AI-2 apoptotic index). Treatment with antioxidant cocktail resulted in a significant decrease in germ cell apoptosis (33% decrease in AI-1, p < 0.05 and 34% decrease in AI-2, p < 0.05) that was accompanied by an improved spermatogenesis (increase in Johnsen's criteria, p < 0.05).

CONCLUSIONS

In a rat model of WBIR, antioxidant treatment ameliorates oxidative stress-induced testicular damage, decreases germ cell apoptosis and improves spermatogenesis.

Radiations and male fertility

During recent years, an increasing percentage of male infertility has to be attributed to an array of environmental, health and lifestyle factors. Male infertility is likely to be affected by the intense exposure to heat and extreme exposure to pesticides, radiations, radioactivity and other hazardous substances. We are surrounded by several types of ionizing and non-ionizing radiations and both have recognized causative effects on spermatogenesis. Since it is impossible to cover all types of radiation sources and their biological effects under a single title, this review is focusing on radiation deriving from cell phones, laptops, Wi-Fi and microwave ovens, as these are the most common sources of non-ionizing radiations, which may contribute to the cause of infertility by exploring the effect of exposure to radiofrequency radiations on the male fertility pattern. From currently available studies it is clear that radiofrequency electromagnetic fields (RF-EMF) have deleterious effects on sperm parameters (like sperm count, morphology, motility), affects the role of kinases in cellular metabolism and the endocrine system, and produces genotoxicity, genomic instability and oxidative stress. This is followed with protective measures for these radiations and future recommendations. The study concludes that the RF-EMF may induce oxidative stress with an increased level of reactive oxygen species, which may lead to infertility. This has been concluded based on available evidences from in vitro and in vivo studies suggesting that RF-EMF exposure negatively affects sperm quality.

Recovery of Spermatogenesis Following Cancer Treatment with Cytotoxic Chemotherapy and Radiotherapy

The survival rates of boys and men with cancer have increased due to advances in cancer treatments; however, maintenance of quality of life, including fertility preservation, remains a major issue. Fertile male patients who receive radiation and/or chemotherapy face temporary, long-term, or permanent gonadal damage, particularly with exposure to alkylating agents and whole-body irradiation, which sometimes induce critical germ cell damage. These cytotoxic treatments have a significant impact on a patient's ability to have their own biological offspring, which is of particular concern to cancer patients of reproductive age. Therefore, various strategies are needed in order to preserve male fertility. Sperm cryopreservation is an effective method for preserving spermatozoa. Advances have also been achieved in pre-pubertal germ cell storage and research to generate differentiated male germ cells from various types of stem cells, including embryonic stem cells, induced pluripotent stem cells, and spermatogonial stem cells. These approaches offer hope to many patients in whom germ cell loss is associated with sterility, but are still experimental and preliminary. This review examines the current understanding of the effects of chemotherapy and radiation on male fertility.

Fatherhood and Sperm DNA Damage in Testicular Cancer Patients

Testicular cancer (TC) is one of the most treatable of all malignancies and the management of the quality of life of these patients is increasingly important, especially with regard to their sexuality and fertility. Survivors must overcome anxiety and fears about reduced fertility and possible pregnancy-related risks as well as health effects in offspring. There is thus a growing awareness of the need for reproductive counseling of cancer survivors. Studies found a high level of sperm DNA damage in TC patients in comparison with healthy, fertile controls, but no significant difference between these patients and infertile patients. Sperm DNA alterations due to cancer treatment persist from 2 to 5 years after the end of the treatment and may be influenced by both the type of therapy and the stage of the disease. Population studies reported a slightly reduced overall fertility of TC survivors and a more frequent use of ART than the general population, with a success rate of around 50%. Paternity after a diagnosis of cancer is an important issue and reproductive potential is becoming a major quality of life factor. Sperm chromatin instability associated with genome instability is the most important reproductive side effect related to the malignancy or its treatment. Studies investigating the magnitude of this damage could have a considerable translational importance in the management of cancer patients, as they could identify the time needed for the germ cell line to repair nuclear damage and thus produce gametes with a reduced risk for the offspring.

Sperm DNA Fragmentation Index and Hyaluronan Binding Ability in Men from Infertile Couples and Men with Testicular Germ Cell Tumor

Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC) and men with testicular germ cell tumor (TGCT). Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI) and the ability of sperm to bind with hyaluronan (HA) was assessed. Results. In comparison with the IC men, the men with TGCT had a higher percentage of sperm with fragmented DNA (median 28% versus 21%; p < 0.01) and a lower percentage of HA-bound sperm (24% versus 66%; p < 0.001). Normal results of both analyses were observed in 24% of IC men and 4% of men with TGCT. Negative Spearman's correlations were found between DFI and the percentage of HA-bound sperm in the whole group and in IC subjects and those with TGCT analyzed separately. Conclusions. Approximately 76% of IC men and 96% with TGCT awaiting orchiectomy demonstrated DNA fragmentation and/or sperm immaturity. We therefore recommend sperm banking after unilateral orchiectomy, but before irradiation and chemotherapy; the use of such a deposit appears to be a better strategy to obtain functionally efficient sperms.

Relationship of spermatozoal DNA fragmentation with semen quality in varicocele-positive men

The aim of the study was to assess the semen quality and levels of spermatozoal nuclear DNA fragmentation in subfertile subjects clinically diagnosed with varicocele, subfertile subjects without varicocele and healthy fertile controls. Semen samples were obtained from 302 subjects. Of them, 115 were healthy fertile controls having normal semen characteristics, 121 subfertile men diagnosed with varicocele, both, clinically and on ultrasonography, while 66 subjects were subfertile with no varicocele. Spermatozoal concentration, percentage motility, morphology and DNA fragmentation were measured. In the study population, deterioration in semen quality-decreased spermatozoal concentration, percentage motility and normal morphology was seen in subfertile subjects, especially with varicocele. Highest spermatozoal DNA fragmentation was observed in varicocele-positive subjects as compared with varicocele-negative subjects and healthy fertile controls. Significant negative correlation was seen between spermatozoal DNA fragmentation and concentration (r = -0.310), motility (r = -0.328) normal morphology, WHO method (r = -0.221) and Tygerberg strict criteria (r = -0.180) in the varicocele-positive subfertile subjects. In conclusion, this study suggests existence of a negative relationship between spermatozoal DNA fragmentation and semen quality in varicocele-positive subfertile subjects.

Paternal Benzo[a]pyrene Exposure Modulates MicroRNA Expression Patterns in the Developing Mouse Embryo

Little attention has been given to how microRNA expression is affected by environmental contaminants exposure. We investigate the effects of paternal exposure to benzo[a]pyrene (B[a]P) on miRNA expression in the developing mouse embryo. Male mice were exposed to B[a]P (150 mg/kg i.p.), and their sperm was used four days later in in-vitro fertilization experiments. Twenty embryos each from 2-, 8-cell and the blastocyst stage were used for genome-wide miRNA expression profiling. Paternal exposure to B[a]P affected the expression of several miRNAs, and the target genes for some of the dysregulated miRNAs were enriched in many different pathways that are likely to be relevant for the developing mouse embryo. By linking the miRNA target genes to publicly available databases, we identified some miRNA target genes that may serve as global markers of B[a]P-mediated genotoxic stress. The dysregulated miRNAs may provide valuable knowledge about potential transgenerational effects of sublethal exposure to chemicals.

Sperm DNA Fragmentation: Origin and Impact on Human Reproduction

Sperm DNA can be damaged due to a multitude of different noxae, which include disease, and occupational and environmental factors. Depending on the magnitude of the damage, such lesions may be repaired by the oocyte or the embryo. If this is not possible, a permanent damage can be manifested leading to mutations of the male genome. In cases where the oocyte or the embryo does not counter these damages to the male genome in terms of repair or an early abortion, sperm DNA damage and fragmentation can be a cause of numerous diseases including childhood cancer.

Risk of birth abnormalities in the offspring of men with a history of cancer: a cohort study using Danish and Swedish national registries

Background

The potential mutagenic effects of cancer therapies and the growing number of young male cancer survivors have given rise to concern about the health of their offspring.

Methods

We identified all singleton children born alive in Denmark between 1994 and 2004 and in Sweden between 1994 and 2005 (n = 1 777 765). Of the 8670 children with a paternal history of cancer, 8162 were conceived naturally and 508 were conceived using assisted reproductive technologies (ARTs) (in vitro fertilization or intracytoplasmatic sperm injection). Of the 1 769 0795 children without a paternal history of cancer, 25 926 were conceived using ARTs. Associations between paternal history of cancer and risk of adverse birth outcomes of children conceived naturally or by ARTs were investigated using log-linear binomial models, yielding risk ratios (RRs) with 95% confidence intervals (CIs). All statistical tests were two-sided.

Results

The offspring of male cancer survivors were more likely to have major congenital abnormalities than the offspring of fathers with no history of cancer (RR = 1.17, 95% CI = 1.05 to 1.31, P = .0043, 3.7% vs 3.2%). However, the mode of conception (natural conception or ARTs) did not modify the association between paternal history of cancer and risk of congenital abnormalities (natural conception, RR = 1.17, 95% CI = 1.04 to 1.31; ARTs, RR = 1.22, 95% CI = 0.80 to 1.87, P_interaction = .84).

Conclusion

We observed a statistically significant but modest increase in the risk of major congenital abnormalities among offspring of males with a history of cancer, independent of the mode of conception.

Sperm DNA integrity in cancer patients before and after cytotoxic treatment

BACKGROUND

We assessed sperm DNA fragmentation index (DFI) in cancer patients before and after treatment to evaluate if sperm DNA integrity is compromised by cancer itself or its treatment.

METHODS

In a prospective study, DFI was assessed in 127 patients diagnosed with testicular germ cell tumours (TGCT), Hodgkin's lymphoma (HL), non-Hodgkin's lymphoma (NHL) and various malignancies. The severity of cancer and tumour markers at diagnosis was recorded. Follow-up DFI after treatment was available in 52 patients who were mostly less severely affected.

RESULTS

In patients diagnosed with TGCT, HL and various malignancies, pretreatment DFI levels were not significantly different from that of proven fertile controls, but in patients with NHL an increased DFI was found. An overall significant decrease in post-treatment DFI (13.2% range 5.0-70.5) compared with pretreatment values (17.1% range 5.1-66.6) was found (P = 0.040). In TGCT patients, post-treatment DFI was significantly higher in patients who were treated with radiotherapy (16.9% range 11.5-39.9) compared with that in patients treated with chemotherapy (CT) alone (10.9% range 5.5-39.9) (P = 0.037). In HL patients, the type of treatment or number of CT cycles was not associated with DFI. Overall, post-treatment DFI in cancer patients was not significantly different from that of proven fertile controls.

CONCLUSIONS

In this study, the presence of cancer does not seem to negatively affect the sperm DNA integrity in TGCT and HL patients; only NHL patients showed increased DFI at the time of diagnosis compared with healthy controls. Our results confirm previous reports that DFI decreases significantly following various anti-cancer treatments. In contrast, radiotherapy in TGCT patients is associated with an increase in DFI compared with CT treatment alone.

Using decision trees to enhance interdisciplinary team work: the case of oncofertility

PURPOSE

Oncofertility, an emerging discipline at the intersection of cancer and fertility, strives to give cancer patients options when they are confronting potential infertility as a consequence of cancer treatment. Fertility preservation decisions must be made before treatment begins, adding stress to the decision-making process.

METHODS

Healthcare providers need to be aware of the intricacies involved in oncofertility decision making, and the often tight time line that patients face when making these decisions. Cancer patient's perspectives may also change, as the dual burden of a cancer diagnosis and potential infertility can cause great flux in emotions.

RESULTS

A provider-facing decision tree was created to enhance patient decision-making capacities and outline the multiple potential intervention points.

CONCLUSIONS

Decision trees, which highlight the important decision points during which providers can approach patients, can be a useful tool to help providers in counseling patients on fertility preservation.

Potential biological role of poly (ADP-ribose) polymerase (PARP) in male gametes

Maintaining the integrity of sperm DNA is vital to reproduction and male fertility. Sperm contain a number of molecules and pathways for the repair of base excision, base mismatches and DNA strand breaks. The presence of Poly (ADP-ribose) polymerase (PARP), a DNA repair enzyme, and its homologues has recently been shown in male germ cells, specifically during stage VII of spermatogenesis. High PARP expression has been reported in mature spermatozoa and in proven fertile men. Whenever there are strand breaks in sperm DNA due to oxidative stress, chromatin remodeling or cell death, PARP is activated. However, the cleavage of PARP by caspase-3 inactivates it and inhibits PARP's DNA-repairing abilities. Therefore, cleaved PARP (cPARP) may be considered a marker of apoptosis. The presence of higher levels of cPARP in sperm of infertile men adds a new proof for the correlation between apoptosis and male infertility. This review describes the possible biological significance of PARP in mammalian cells with the focus on male reproduction. The review elaborates on the role played by PARP during spermatogenesis, sperm maturation in ejaculated spermatozoa and the potential role of PARP as new marker of sperm damage. PARP could provide new strategies to preserve fertility in cancer patients subjected to genotoxic stresses and may be a key to better male reproductive health.

Male gonadal toxicity

Cancer treatment with chemotherapy or radiotherapy causes gonadal toxicity in male patients. The endpoint of most concern for future reproductive options is the induction of prolonged azoospermia, which may or may not be reversible. The immediate effects of therapy and its reversibility are most readily observed in post-pubertal patients, but the same antineoplastic regimens given to prepubertal males can induce permanent azoospermia. The probability of permanent azoospermia is related to the specific agents used and their doses. The most damaging are alkylating agents (particularly chlorambucil, procarbazine, cyclophosphamide, melphalan, and busulfan), cisplatin and radiation to the region of the testicles.

Risk-Adapted Treatment in Clinical Stage I Nonseminomatous Germ Cell Testicular Cancer: The SWENOTECA Management Program

Purpose

To offer minimized risk-adapted adjuvant treatment on a nationwide basis for patients with clinical stage 1 (CS1) nonseminomatous germ-cell testicular cancer (NSGCT). The aim was to reduce the risk of relapse and thereby reducing the need of later salvage chemotherapy while maintaining a high cure rate.

Patients and Methods

From 1998 to 2005, 745 Norwegian and Swedish patients were included into a prospective, community-based multicenter Swedish and Norwegian Testicular Cancer Project (SWENOTECA) management program. Treatment strategy depended on the presence or absence of vascular tumor invasion (VASC). VASC-positive patients were recommended brief adjuvant chemotherapy (ACT) with bleomycin, etoposide, and cisplatin (BEP), whereas VASC-negative patients could choose between ACT and surveillance.

Results

At a median follow-up of 4.7 years, there have been 51 relapses. On surveillance, 41.7% of VASC+ patients relapsed, compared with 13.2% of VASC− patients. After one course of BEP, 3.2% of VASC+ and 1.3% of VASC− patients relapsed. The toxicity of adjuvant BEP was low. Eight patients have died, none died from progressive disease.

Conclusion

One course of adjuvant BEP reduces the risk of relapse by approximately 90% in both VASC+ and VASC− CS1 NSGCT, and may be a new option as initial treatment for all CS1 NSGCT. One course of adjuvant BEP for VASC+ CS1 reduces the total burden of chemotherapy compared with surveillance or two courses of BEP. SWENOTECA currently recommends one course of BEP as standard treatment of VASC+ CS1 NSGCT, whereas both surveillance and one course of BEP are options for VASC− CS1 NSGCT.

Apoptotic-like changes in equine spermatozoa separated by density-gradient centrifugation or after cryopreservation

The objective was to evaluate apoptotic markers in ejaculated equine spermatozoa after separation by density-gradient centrifugation and after cryopreservation. Subpopulations of percoll-separated equine spermatozoa differed (P<0.05) in the percentage of live, caspase-activated spermatozoa (2.9+/-0.7% vs 14.2+/-6.4%; mean+/-S.E.M.), low mitochondrial membrane potential (MMP; 6.8+/-1.1 vs 23.8+/-3.7), altered plasma membrane permeability (1.3+/-0.2 vs 3.0+/-0.5), DNA fragmentation (2.0+/-1.3 vs 14.3+/-3.6), total motility (81.8+/-3.3 vs 35.1+/-5.4), and progressive motility (66.3+/-4.3 vs 24.1+/-4.5) for high-density versus low-density subpopulations, respectively. Phosphatidylserine externalization did not differ (P=0.67) between the high- and low-density subpopulations (2.6+/-0.7 vs 3.1+/-0.9). After cryopreservation, equine spermatozoa differed (P<0.01) in the percentage of active caspases (19.1+/-1.6 vs 52.1+/-2.8), low MMP (18.2+/-2.5 vs 48.7+/-2.6), altered plasma membrane permeability (6.8+/-1.7 vs 17.6+/-2.0), total motility (75.5+/-2.4 vs 45.2+/-5.6), and progressive motility (53.9+/-3.1 vs 28.3+/-4.5) for pre-freeze versus cryopreserved spermatozoa. There was no difference (P=0.21) in percentage of DNA fragmented cells before (5.5+/-1.2) versus after cryopreservation (6.6+/-1.1). We concluded that apoptotic-like changes were detectable in ejaculated equine spermatozoa and were more prevalent after cryopreservation.

Human sperm DNA fragmentation: correlation of TUNEL results as assessed by flow cytometry and optical microscopy

An association between DNA fragmentation in sperm determined by the terminal deoxynucleotidyl transferase [TdT]-mediated deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) assay and the incidence of reproductive failure has been reported, either using flow cytometry or optical microscopy. However, the results obtained using each of these two approaches are different. Since there is a relative lack of studies standardizing these two approaches, the direct comparison of the results described in the different articles is difficult at present. To allow the comparison of the TUNEL results obtained using flow cytometry and optical microscopy, we applied these two approaches in a total of 66 human sperm samples. A positive correlation is detected in the TUNEL results as measured by flow cytometry and optical microscopy (Spearman; r = 0.720, P < 0.001). The percentage of TUNEL-positive spermatozoa assessed by flow cytometry is 2.6 times higher than that detected in optical microscopy (39.7% +/- 23.1% versus 15.3% +/- 10.3%). Although there is a good correlation of the TUNEL results obtained by flow cytometry and optical microscopy, the percentages obtained with either technique are different. Therefore, the TUNEL results described in the present work should be valuable to compare the results described in many independent articles, using either optical microscopy or flow cytometry.

Characterization of sperm chromatin quality in testicular cancer and Hodgkin's lymphoma patients prior to chemotherapy

BACKGROUND

Although the incidences of testicular cancer and Hodgkin's lymphoma have increased in young men over the past decade, combination chemotherapy has improved survival. As fertility is of importance to these patients, characterization of sperm chromatin structure is needed. We assessed sperm chromatin in testicular cancer and Hodgkin's lymphoma patients prior to chemotherapy, in comparison with control community and idiopathic infertile volunteers.

METHODS

DNA damage was assessed with the sperm chromatin structure assay (SCSA), terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and comet assays; reactive thiols (SH) and DNA compaction were determined with the monobromobimane (mBBr) and chromomycin A3 (CMA3) assays, respectively.

RESULTS

Both testicular cancer (37%) and Hodgkin's lymphoma (81%) patients had normospermic samples with increased DNA damage, compared with controls. Cancer patients also had higher reactive thiols and CMA3 staining, indicating low DNA compaction.

CONCLUSIONS

Sperm DNA integrity and compaction were affected in testicular cancer and Hodgkin's lymphoma patients prior to chemotherapy. Although SCSA, TUNEL and comet assays all detected DNA damage, the latter was optimal for use in cancer patients. A combination of the comet assay with tests that evaluate sperm DNA compaction, such as flow cytometry-based CMA3 and mBBr assays, is a reliable strategy to characterize sperm chromatin quality in cancer patients at the time of sperm banking.

The effect of cancer on sperm DNA fragmentation as measured by the sperm chromatin dispersion test

The percentage of spermatozoa with fragmented DNA from cancer patients before surgery, chemotherapy, or radiotherapy treatments was compared with infertile male patients in an assisted reproduction program and with sperm donors of proven fertility. The percentages of DNA fragmentation were 34.3% in cancer patients, 30.9% in infertile men whose partners did not become pregnant, 28.8% in men who partners became pregnant, and 10.8% in fertile sperm donors. The DNA fragmentation of sperm donors was statistically significantly lower compared the other groups. No statistically significant differences were found in the levels of DNA fragmentation when comparing cancer types, including those of testicular origin.

Effectiveness of sperm banking in adolescents and young adults with cancer

BACKGROUND

Improving success in the treatment of cancer has resulted in an increasing number of survivors. An important quality of life issue among younger survivors is the ability to have a family. Current gonadotoxic treatments for cancer pose a challenge to future fertility. Preservation of fertility after gonadotoxic therapy is an important consideration for these patients. In a regional center, the authors evaluated efficacy and utilization of sperm banking for preservation of male fertility in adolescents and young adults (AYA) with cancer.

METHODS

A retrospective chart review was conducted to obtain data on clinical features, andrology, and fertility from patients (ages < 30 years) who cryopreserved samples of semen from 1995-2005.

RESULTS

Of 821 newly diagnosed male AYA cancer patients, aged 14-30 years, only 146 (17.8%) used sperm cryopreservation technology. Patients who used their cryopreserved semen for attempted conception had a 36.4% success rate with intrauterine insemination (IUI) and a 50.0% clinical pregnancy rate with in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

CONCLUSIONS

Sperm cryopreservation by AYA males with cancer is an efficacious method for preserving future fertility. Awareness and employment of assisted reproductive technologies needs to be implemented by an interdisciplinary team of experts caring for these patients and can result in successful paternity in males after treatment for cancer.