Highly sensitive quantitative telomerase assay of diagnostic testicular biopsy material predicts the presence of haploid spermatogenic cells in therapeutic testicular biopsy in men with Sertoli cell-only syndrome

Evaluating the Predictive Value of Diagnostic Testicular Biopsy for Sperm Retrieval Outcomes in Men with Non-Obstructive Azoospermia

BACKGROUND

Non-obstructive azoospermia (NOA) presents a challenge in male infertility management. This study aimed to assess the efficacy of diagnostic testicular biopsy (DTB) in predicting sperm retrieval success via therapeutic testicular biopsy (TTB) and to understand the role of systemic inflammation in microdissection testicular sperm extraction (mTESE) outcomes.

METHODS

A retrospective analysis was conducted on 50 NOA males who underwent mTESE at the University of Ioannina's Department of Urology from January 2017 to December 2019. All participants underwent thorough medical evaluations, including semen analyses and endocrinological assessments.

RESULTS

DTB did not detect spermatozoa in half of the patients who later showed positive sperm findings in TTB. Preoperative variables, such as age, plasma levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (TT), prolactin (PRL), estradiol (E2), and inflammation biomarkers (neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-eosinophil ratio (MER)), were not consistently predictive of sperm retrieval success. Notably, TTB-negative patients had elevated NLR and PLR values, suggesting a possible link between systemic inflammation and reduced sperm retrieval during mTESE.

CONCLUSIONS

The findings question the necessity of an initial DTB, which might provide misleading results. A negative DTB should not deter further TTB or intracytoplasmic sperm injection (ICSI) attempts. The study emphasizes the need for further research to refine diagnostic approaches and deepen the understanding of factors influencing sperm retrieval in NOA patients, ultimately enhancing their prospects of biological parenthood.

Functional association between telomeres, oxidation and mitochondria

Prior research has substantiated the vital role of telomeres in human fertility. Telomeres are prerequisites for maintaining the integrity of chromosomes by preventing the loss of genetic material following replication events. Little is known about the association between sperm telomere length and mitochondrial capacity involving its structure and functions. Mitochondria are structurally and functionally distinct organelles that are located on the spermatozoon's midpiece. Mitochondria produce adenosine triphosphate (ATP) through oxidative phosphorylation (OXPHOS), which is necessary for sperm motility and generate reactive oxygen species (ROS). While a moderate concentration of ROS is critical for egg-sperm fusion, and fertilization, excessive ROS generation is primarily related to telomere shortening, sperm DNA fragmentation, and alterations in the methylation pattern leading to male infertility. This review aims to highlight the functional connection between mitochondria biogenesis and telomere length in male infertility, as mitochondrial lesions have a damaging impact on telomere length, leading both to telomere lengthening and reprogramming of mitochondrial biosynthesis. Furthermore, it aims to shed light on how both inositol and antioxidants can positively affect male fertility.

Sertoli cell-only syndrome: etiology and clinical management

Almost 50% of infertility cases are due to male factors, and spermatogenesis failure is one of the most severe forms of male infertility. Sertoli cell-only syndrome (SCOS) also known as germ cell aplasia is characterized by azoospermia in which the seminiferous tubules of testicular biopsy are lined only with Sertoli cells. The definitive diagnosis of SCOS is by diagnostic testicular biopsy. Although SCOS may be a result of Klinefelter syndrome, most of the SCOS men have a normal karyotype. Along with genetic aberrations, signaling pathways and endocrine processes might be major factors in the development of SCOS. Sperm retrieval and intracytoplasmic sperm injection (ICSI) are available treatments for SCOS. However, some SCOS patients do not have therapeutic options to help them having a biological child. This review aims to summarize our present knowledge about SCOS and to highlight the importance of future researches in the diagnosis and treatment of this disorder.

Undecylprodigiosin induced apoptosis in P388 cancer cells is associated with its binding to ribosome

Prodigiosins (PGs) are a family of natural red pigments with anticancer activity, and one member of the family has entered clinical phase II trials. However, the anticancer mechanisms of PGs remain largely unclear. This study was designed to investigate the molecular basis of anticancer activity of UP, a derivative of PGs, in P388 cells. By introducing pharmacological inhibitors and utilizing a variety of analytical approaches including western blotting, flow cytometry and confocal laser microscopy, we found that UP inhibited proliferation of P388 via arresting cells at G2/M phase and inducing cells apoptosis, which was related to the activation of P38, JNK rather than ERK1/2 signaling. ROS regeneration and acidification in cells appear not involved in UP induced apoptosis. Furthermore, utilizing mass spectrometry, sucrose density gradient fractionation and immunofluorescence staining, we discovered that UP was apparently located at ribosome. These results together indicate that ribosome may be the potential target of UP in cancer cells, which opened a new avenue in delineating the anticancer mechanism of PGs.

Telomerase and the endocrine system

Telomeres are nucleoprotein complexes located at the ends of chromosomes that have a critical role in the maintenance of chromosomal integrity. This involvement is based on complex secondary and tertiary structures that rely on DNA-DNA, DNA-protein and protein-protein interactions. De novo synthesis and maintenance of telomere repeats is controlled by telomerase, a specialized complex that consists of a telomerase RNA component and a protein component--telomerase reverse transcriptase. When telomerase is silent (its default state in differentiated somatic cells), chromosomes shorten with every cell division, thus limiting the lifespan of the cells (the process of senescence) and preventing unlimited cell proliferation, which might eventually lead to the development of cancer. During this process, occasionally, a cell can activate telomerase, which stabilizes short telomeres and enables immortalization-a process essential for malignant transformation. Thus, although telomere erosion is a barrier to malignant progression, paradoxically, in certain circumstances it might also trigger tumorigenesis. A number of studies have demonstrated unequivocally that reactivation of telomerase in the presence of short telomeres is one of the most common features of human cancers, including those of the endocrine system.

Enhancement of extra chromosomal recombination in somatic cells by affecting the ratio of homologous recombination (HR) to non-homologous end joining (NHEJ)

Advancements in somatic cell gene targeting have been slow due to the finite lifespan of somatic cells and the overall inefficiency of homologous recombination. The rate of homologous recombination is determined by mechanisms of DNA repair, and by the balance between homologous recombination (HR) and non-homologous end joining (NHEJ). A plasmid-to-plasmid, extra chromosomal recombination system was used to study the effects of the manipulation of molecules involved in NHEJ (Mre11, Ku70/80, and p53) on HR/NHEJ ratios. In addition, the effect of telomerase expression, cell synchrony, and DNA nuclear delivery was examined. While a mutant Mre11 and an anti-Ku aptamer did not significantly affect the rate of NHEJ or HR, transient expression of a p53 mutant increased overall HR/NHEJ by 2.5 fold. However, expression of the mutant p53 resulted in increased aneuploidy of the cultured cells. Additionally, we found no relationship between telomerase expression and changes in HR/NHEJ. In contrast, cell synchrony by thymidine incorporation did not induce chromosomal abnormalities, and increased the ratio of HR/NHEJ 5-fold by reducing the overall rate of NHEJ. Overall our results show that attempts at reducing NHEJ by use of Mre11 or anti-Ku aptamers were unsuccessful. Cell synchrony via thymidine incorporation, however, does increase the ratio of HR/NHEJ and this indicates that this approach may be of use to facilitate targeting in somatic cells by reducing the numbers of colonies that need to be analyzed before a HR is identified.

Quality of reporting of test accuracy studies in reproductive medicine: impact of the Standards for Reporting of Diagnostic Accuracy (STARD) initiative

OBJECTIVE

To evaluate the extent to which test accuracy studies published in two leading reproductive medicine journals in the years 1999 and 2004 adhered to the Standards for Reporting of Diagnostic Accuracy (STARD) initiative parameters, and to explore whether the introduction of the STARD statement has led to an improved quality of reporting.

DESIGN

Structured literature search. Articles that reported on the diagnostic performance of a test in comparison with a reference standard were eligible for inclusion. For each article we scored how well the 25 items of the STARD checklist were reported. These items deal with the study question, study participants, study design, test methods, reference standard, statistical methods, reporting of results, and conclusions. We calculated the total number of reported STARD items per article, summary scores for each STARD item, and the average number of reported STARD items per publication year.

SETTING

Not applicable.

PATIENT(S)

Not applicable.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Quality of reporting.

RESULT(S)

We found 24 studies reporting on test accuracy in reproductive medicine in 1999 and 27 studies in 2004. The mean number of reported STARD items for articles published in 1999 was 12.1 +/- 3.3 (range 6.5-20) and 12.4 +/- 3.2 (range 7-17.5) in 2004, after publication of the STARD statement. Overall, less than half of the studies reported adequately on 50% or more of the STARD items. The reporting of individual items showed a wide variation. There was no significant improvement in mean number of reported items for the articles published after the introduction of the STARD statement.

CONCLUSION(S)

Authors of test accuracy studies in the two leading fertility journals poorly report the design, conduct, methodology, and statistical analysis of their study. Strict adherence to the STARD guidelines should be encouraged.

Testicular expression of survivin and human telomerase reverse transcriptase (hTERT) associated with spermatogenic function in infertile patients

AIM

To characterize the coexpression of survivin, an inhibitor of apoptosis (IAF), and human telomerase reverse transcriptase (hTERT) in human testes with varying spermatogenic function.

METHODS

Transcript levels of survivin mRNA and hTERT mRNA were determined in normal testes (n=11) and testes with defective spermatogenesis (n=28) using real-time reverse-transcription polymerase chain reaction (RT-PCR). The histological work-up was performed according to a modified Johnsen score.

RESULTS

Expressions of both survivin and hTERT were highest at median levels of 96.8 and 709 in normal spermatogenesis and dropped to 53.3 and 534 in testes with postmeiotic spermatogenic arrest (n=10). In severe spermatogenic failure (n=18), survivin expression was lacking in most specimens (n=16), whereas at least low levels of testicular hTERT expression were largely detectable with a normalized expression of 73 in premeiotic spermatogenic arrest (n=7) and 45 in patients with Sertoli cell-only syndrome (SCOS) (n=3). Both survivin and hTERT expressions increased with a progressing Johnsen score (P for trend=0.001).

CONCLUSION

Although both survivin and hTERT are correlated with spermatogenic function, they show different expression patterns in testes of infertile patients. These findings substantiate results from studies in the rodent testis suggesting a predominant expression of survivin in meiotically dividing germ cells.

Expression levels of the inhibitor of apoptosis survivin in testes of patients with normal spermatogenesis and spermatogenic failure

OBJECTIVE

To determine the expression of the inhibitor of apoptosis survivin in men with and without spermatogenic failure.

DESIGN

Prospective case study.

SETTING

Two university-based infertility clinics.

PATIENT(S)

Forty-nine infertile men presenting with azoospermia.

INTERVENTION(S)

Testicular biopsies for histopathological assessment and analyses of survivin expression levels by real-time reverse transcription-polymerase chain reaction. Survivin levels were normalized to expression of the housekeeping porphobilinogen deaminase gene.

MAIN OUTCOME MEASURE(S)

Correlation of the histological findings with normalized survivin expression levels.

RESULTS(S)

Testicular survivin mRNA expression was highest in normal spermatogenesis (n = 14). Decreased expression was observed in patients with spermatogenesis disorders. The expression level correlated with the degree of spermatogenic failure. While it was reduced in postmeiotic maturation arrest (n = 11), a lack of expression was seen in most specimens (10 of 12) with premeiotic maturation arrest and in all of those with Sertoli cell-only syndrome (n = 12).

CONCLUSION(S)

These data indicate that survivin is expressed in human germ cells and might be involved in apoptosis control during spermatogenesis. Decreased survivin expression in spermatogenic disorders may contribute to the accelerated germ cell apoptosis observed in male idiopathic infertility.

Role of testicular tissue telomerase assay for the prediction of the presence of testicular spermatozoa in azoospermic men with varicoceles, pre- and post-varicocelectomy

We evaluated the reproductive potential of frozen/thawed testicular spermatozoa of azoospermic men with left varicocele. The role of testicular tissue telomerase assay (TTA) in the prediction of the presence of testicular spermatozoa pre- and post-varicocelectomy was investigated, as well. Therapeutic testicular biopsy and TTA were performed in 82 nonobstructed azoospermic (NOA) men with varicoceles. Testicular spermatozoa were found in 33 men and processed for cryopreservation. Oocytes were later recovered from the spouses of the latter azoospermic men with varicoceles and injected with frozen/thawed testicular spermatozoa. Among the 49 men who were negative for testicular spermatozoa, 22 men underwent subsequently subinguinal microsurgical varicocelectomy. A total of 198 mature oocytes were successfully injected and 101 were normally fertilized and subsequently cleaved. Transfer of these 101 embryos in 26 women resulted in nine full-term pregnancies. Thirteen healthy babies were delivered. A cut-off value of TTA of 39 TPG U microg(-1) protein had an overall diagnostic accuracy equal to 90.2% to predict the presence of testicular spermatozoa pre-varicocelectomy. Within the group of men who were negative for testicular spermatozoa a cut-off value of TTA equal to 28 TPG U microg(-1) protein (pre-varicocelectomy) had a 84.2 % diagnostic accuracy to recognize the men who would become positive for either ejaculated or testicular spermatozoa post-varicocelectomy. Testicular spermatozoa can be found in 40% of NOA men with left varicocele. Ooplasmic injections with frozen/thawed testicular spermatozoa have a role in the therapeutic management of non-obstructive azoospermia associated with varicocele. Pre-varicocelectomy, a TTA cut-off value equal to 39 TPG U microg(-1) protein has a 90.2% diagnostic accuracy to indicate the men positive/negative for testicular spermatozoa. In addition, pre-varicocelectomy, a cut-off value equal to 28 TPG U microg(-1) protein has a 84.2% diagnostic accuracy to identify those men with varicoceles without testicular spermatozoa, who will become positive/negative for spermatozoa (either ejaculated or testicular) post-varicocelectomy.

Cytogenetics and fluorescence in situ hybridization assessment of sex-chromosome mosaicism in Klinefelter’s syndrome

A retrospective study was carried out in 152 infertile men to determine the prevalence of sex chromosome abnormalities among non-obstructive azoospermic and severe oligospermic men (n = 51) and to evaluate the feasibility of fluorescence in situ hybridization (FISH) techniques to assess mosaicism in Klinefelter's patients in comparison with conventional cytogenetics. Cytogenetic analysis were performed for 51 infertile men and among 14 chromosomal abnormalities found, nine were compatible with Klinefelter's syndrome. FISH staining with a CEP X/CEP Y probes were performed for Klinefelter's patients and for five of them; testes were biopsied for histopathologic examination. Six Klinefelter's patients showed a non-mosaic 47,XXY and three showed a 47,XXY/46,XY mosaic by G or R banding analysis of 20 cells with a ratio of 17%, 20% and 33%, respectively. FISH analysis confirmed mosaicism in only one patient (the first) in whom a third cells population was found. There was no relationship between the ratios of mosaicism by banding and FISH analysis. Conventional histopathologic findings in five non-mosaic Klinefelter's patients confirm the diagnosis of Sertoli Only Cells syndrome. FISH is recommended in Klinefelter's syndrome to define exactly the cytogenetic statute as mosaic or non-mosaic and then discussing prognosis and decision regarding fertility counseling.

The role of ultrasonographically guided puncture of the human rete testis in the therapeutic management of nonobstructive azoospermia

We attempted to characterize the cells collected from the rete testis via ultrasonographically guided puncture. Unilateral puncture of the rete testis was performed in nine men with obstructive azoospermia and 51 men with nonobstructive azoospermia. All the aspirated samples from the rete testis were observed via confocal scanning laser microscope and some of them after fluorescent in situ hybridization techniques. Then therapeutic testicular biopsy was performed in the punctured testis of each man. Spermatozoa were found in all rete testis samples and all biopsy samples from obstructed men. Twenty-two nonobstructed men demonstrated absence of spermatozoa in biopsy samples. Twenty-nine nonobstructed men showed spermatozoa in biopsy material and 24 of these men (82%) had demonstrated spermatozoa in rete testis samples. There were no significant differences in fertilization and cleavage rate between intracytoplasmic sperm injection trials using biopsy spermatozoa and rete testis spermatozoa both in obstructed and nonobstructed men. Considering that puncture of the rete testis does not reduce the volume of testicular parenchyma, is less invasive and apparently causes less detrimental effect on testicular vasculature than biopsy, puncture of rete testis is recommended as first line approach for the treatment of azoospermic men. If puncture is negative for spermatozoa in nonobstructed men, biopsy is indicated.

Use of a highly sensitive quantitative telomerase assay in intracytoplasmic sperm injection programmes for the treatment of 47,XXY non-mosaic Klinefelter men

We evaluated the role of the sensitive quantitative telomerase assay (SQTA) in the management of men with non-mosaic Klinefelter's syndrome (KS). Diagnostic testicular biopsy (DTB) was performed in 24 men with KS. A part of the DTB was stained and the remaining fragment was processed for the SQTA. After 3-18 months, a therapeutic testicular biopsy (TTB) was performed in the same testicle and the recovered specimens were processed to identify spermatozoa. Men with a SQTA outcome equal to 0.00 Units microg-1 protein (n = 7) demonstrated therapeutic testicular biopsy material that was negative for spermatogenic cells. In five men with a SQTA outcome of 8.11-38.03 Units microg-1, the most advanced germ cell was the spermatogonium/primary spermatocyte. In the remaining 12 men, the most advanced spermatogenic cell in the TTB was the spermatozoon. In these men, the SQTA outcome was equal to 25.76-92.68 Units microg-1 protein. Using 39.00 Units microg-1 protein as a cut-off value, the accuracy of the SQTA in identifying men positive for spermatozoa was 91.6%. It appears that the SQTA has a role for identifying non-mosaic KS men who have testicular spermatozoa.

Predictive value of testicular histology in secretory azoospermic subgroups and clinical outcome after microinjection of fresh and frozen-thawed sperm and spermatids

BACKGROUND

A retrospective study was carried out on 159 treatment cycles in 148 secretory azoospermic patients to determine whether histopathological secretory azoospermic subgroups were predictive for gamete retrieval, and to evaluate outcome of microinjection using fresh or frozen-thawed testicular sperm and spermatids.

METHODS

Sperm and spermatids were recovered by open testicular biopsy and microinjected into oocytes. Fertilization and pregnancy rates were assessed.

RESULTS

In hypoplasia, 97.7% of the 44 patients had late spermatids/sperm recovered. In maturation-arrest (MA; 47 patients), 31.9% had complete MA, and 68.1% incomplete MA due to a focus of early (36.2%) or late (31.9%) spermiogenesis. Gamete retrieval was achieved in 53.3, 41.2 and 93.3% of the cases respectively. In Sertoli cell-only syndrome (SCOS; 57 patients), 61.4% were complete SCOS, whereas incomplete SCOS cases showed one focus of MA (5.3%), or of early (29.8%) and late (3.5%) spermiogenesis. Only 29.8% of the patients had a successful gamete retrieval, 2.9% in complete and 77.3% in incomplete SCOS cases. In total, there were 87 ICSI, 39 elongated spermatid injection (ELSI) and 33 round spermatid injection (ROSI) treatment cycles, with mean values of fertilization rate of 71.4, 53.6 and 17%, and clinical pregnancy rates of 31.7, 26.3 and 0% respectively.

CONCLUSIONS

Histopathological subgroups were positively correlated with successful gamete retrieval. No major outcome differences were observed between testicular sperm and elongated spermatids, either fresh or frozen-thawed. However, injection of intact round-spermatids showed very low rates of fertilization and no pregnancies.

Quantification of telomerase activity, porphobilinogen deaminase and human telomerase reverse transcriptase mRNA in testicular tissue - new parameters for a molecular diagnostic classification of spermatogenesis disorders

The aim of the study was to evaluate the quantitative detection of human telomerase reverse transcriptase (hTERT) mRNA and telomerase activity as new molecular diagnostic parameters for a subclassification of spermatogenesis disorders. Telomerase activity was detected by a quantitative telomerase PCR ELISA, and hTERT mRNA expression was quantified by fluorescence real-time RT-PCR in a LightCycler in cryopreserved testicular tissue specimens. This was paralleled by a histological workup. The discriminant analysis showed that detection of normalized hTERT expression was able to correctly classify 89.0% of the investigated tissue specimens into the subgroups of full spermatogenesis, maturation arrest or Sertoli-cell-only syndrome. In contrast, discriminant analysis revealed an only 58% accuracy of telomerase activity for the investigated tissue specimens. This study shows that the quantification of hTERT expression in testicular tissue by real-time fluorescence RT-PCR is well suited for correctly classifying spermatogenesis disorders and proved to be markedly superior to the determination of telomerase activity.