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Background: Radiotherapy is used routinely to treat testicular cancer. Testicular cells vary in radio-sensitivity and the aim of this study was to investigate cellular and molecular changes caused by low dose irradiation of mice testis and to identify transcripts from different cell types in the adult testis.Methods: Transcriptome profiling was performed on total RNA from testes sampled at various time points (n = 17) after 1 Gy of irradiation. Transcripts displaying large overall expression changes during the time series, but small expression changes between neighbouring time points were selected for further analysis. These transcripts were separated into clusters and their cellular origin was determined. Immunohistochemistry and in silico quantification was further used to study cellular changes post-irradiation (pi).Results: We identified a subset of transcripts (n = 988) where changes in expression pi can be explained by changes in cellularity. We separated the transcripts into five unique clusters that we associated with spermatogonia, spermatocytes, early spermatids, late spermatids and somatic cells, respectively. Transcripts in the somatic cell cluster showed large changes in expression pi, mainly caused by changes in cellularity. Further investigations revealed that the low dose irradiation seemed to cause Leydig cell hyperplasia, which contributed to the detected expression changes in the somatic cell cluster.Conclusions: The five clusters represent gene expression in distinct cell types of the adult testis. We observed large expression changes in the somatic cell profile, which mainly could be attributed to changes in cellularity, but hyperplasia of Leydig cells may also play a role. We speculate that the possible hyperplasia may be caused by lower testosterone production and inadequate inhibin signalling due to missing germ cells.

More than half the pregnant women in the Western world report taking mild analgesics. These pharmaceutical compounds have been associated with congenital cryptorchidism in humans, the best-known risk factor for low semen quality and testicular germ cell cancer. Furthermore, some of these mild analgesics exert potent anti-androgenic effects in the male rat and several endocrine-disrupting compounds, known to alter masculinization, have also been shown to be potent inhibitors of prostaglandin (PG) synthesis similar to mild analgesics. Using a 3-day ex vivo organotypic model system based on gestational day 14.5 rat testes, we herein show that testosterone production was inhibited by paracetamol, at doses of 0.1??m to 100??m. Similar results were obtained for aspirin (1?100??m) and indomethacin (10??m). The production of the other Leydig cell hormone, Insl3, was not disrupted by exposure to paracetamol. Investigations of the gross anatomy of the testis as well as Leydig cells number and rate of gonocyte apoptosis after the 3?days of ex vivo differentiation showed no significant effect of the analgesics tested compared with controls. These data indicate therefore that mild analgesics specifically inhibit testosterone production in rat foetal testes in vitro and that these compounds had no effect on gonocyte survival. Parallel determinations of prostaglandin D2 (PGD2) production indicated that the effects of paracetamol and aspirin on PGD2 and testosterone were not connected, whereas the effects of indomethacin were correlated. We conclude that mild analgesics exert direct and specific anti-androgenic effects in rat foetal testis in our experimental setup and that the mechanism of action is probably uncoupled from the inhibition of PG synthesis.

Prompted by the recently reported expression of POU5F1 (OCT3/4) in epididymis, a panel of markers for carcinoma in situ (CIS) testis and testicular germ cell tumours (TGCT), including AP-2¿(TFAP2C), NANOG, OCT3/4, KIT, placental-like alkaline phosphatase (PLAP), M2A/PDPN and MAGE-A4 were examined by immunohistochemistry or in situ hybridisation in urogenital epithelia, which may interfere with detection of CIS cells in semen. In addition to OCT3/4, the expression of AP-2¿ and NANOG or their variants was detected in urogenital epithelia, while other CIS markers, including PLAP/alkaline phosphatase were absent. A combination of immunocytological staining for AP-2¿ or OCT3/4 and rapid cytochemical alkaline phosphatase reaction was subsequently developed. This approach was tested in 22 patients with TGCT. In 14 patients (63.6%), double stained cells were found and thus the method was proven suitable for the detection of CIS cells in semen. In conclusion, transcription factors related to pluripotency and undifferentiated state of cells, which most likely have several variants or modifications, are unexpectedly detected using currently available antibodies in urogenital epithelial cells which may be shed into semen. Combining the immunohistochemical nuclear markers with a rapid cytochemical alkaline phosphatase reaction for detection of CIS cells in ejaculates may provide a more reliable diagnostic method.

Vitamin D (VD) is important for male reproduction in mammals and the VD receptor (VDR) and VD-metabolizing enzymes are expressed in human spermatozoa. The VD-inactivating enzyme CYP24A1 titrates the cellular responsiveness to VD, is transcriptionally regulated by VD, and has a distinct expression at the sperm annulus. Here, we investigated if CYP24A1 expression serves as a marker for VD metabolism in spermatozoa, and whether CYP24A1 expression was associated with semen quality. We included 130 men (53 healthy young volunteers and 77 subfertile men) for semen analysis and immunocytochemical (ICC) detection of CYP24A1. Another 40 men (22 young, 18 subfertile) were tested for in vitro effects of 1,25(OH)(2) D(3) on intracellular calcium concentration ([Ca(2+) ](i) ) and sperm motility. Double ICC staining showed that CYP24A1 and VDR were either concomitantly expressed or absent in 80% of the spermatozoa from young men. The median number of CYP24A1-expressing spermatozoa was 1% in subfertile men and thus significantly (p 3% CYP24A1-positive spermatozoa distinguished young men from subfertile men with a sensitivity of 66.0%, a specificity of 77.9% and a positive predictive value of 98.3%. Functional studies revealed that 1,25(OH)(2) D(3) increased [Ca(2+) ](i) and sperm motility in young healthy men, while 1,25(OH)(2) D(3) was unable to increase motility in subfertile patients. In conclusion, we suggest that CYP24A1 expression at the annulus may serve as a novel marker of semen quality and an objective proxy for sperm function.

Genetic variants, including single-nucleotide polymorphisms (SNPs), are key determiners of interindividual differences in treatment efficacy and toxicity in childhood acute lymphoblastic leukemia (ALL). Although up to 13 chemotherapeutic agents are used in the treatment of this cancer, it remains a model disease for exploring the impact of genetic variation due to well-characterized cytogenetics, drug response pathways and precise monitoring of minimal residual disease. Here, we have selected clinically relevant genes and SNPs through literature screening, and on the basis of associations with key pathways, protein-protein interactions or downstream partners that have a role in drug disposition and treatment efficacy in childhood ALL. This allows exploration of pathways, where one of several genetic variants may lead to similar clinical phenotypes through related molecular mechanisms. We have designed a cost-effective, high-throughput capture assay of ∼25 000 clinically relevant SNPs, and demonstrated that multiple samples can be tagged and pooled before genome capture in targeted enrichment with a sufficient sequencing depth for genotyping. This multiplexed, targeted sequencing method allows exploration of the impact of pharmacogenetics on efficacy and toxicity in childhood ALL treatment, which will be of importance for personalized chemotherapy. © 2011 Macmillan Publishers Limited All rights reserved.

A recent decline in onset of puberty - especially among girls - has been observed, first in the US in the mid-1990s and now also in Europe. The development of breast tissue in girls occurs at a much younger age and the incidence of precocious puberty (PP) is increasing. Genetic factors and increasing prevalence of adiposity may contribute, but environmental factors are also likely to be involved. In particular, the widespread presence of endocrine-disrupting chemicals (EDCs) is suspected to contribute to the trend of earlier pubertal onset. The factors regulating the physiological onset of normal puberty are poorly understood. This hampers investigation of the possible role of environmental influences. There are many types of EDCs. One chemical may have more than one mode of action and the effects may depend on dose and duration of the exposure, as well as the developmental stage of the exposed individual. There may also be a wide range of genetic susceptibility to EDCs. Human exposure scenarios are complex and our knowledge about effects of mixtures of EDCs is limited. Importantly, the consequences of an exposure may not be apparent at the actual time of exposure, but may manifest later in life. Most known EDCs have oestrogenic and/or anti-androgenic actions and only few have androgenic or anti-oestrogenic effects. Thus, it appears plausible that they interfere with normal onset of puberty. The age at menarche has only declined by a few months whereas the age at breast development has declined by 1 year; thus, the time span from initiation of breast development to menarche has increased. This may indicate an oestrogen-like effect without concomitant central activation of the hypothalamic-pituitary axis. The effects may differ between boys and girls, as there are sex differences in age at onset of puberty, hormonal profiles and prevalence of precocius puberty.

The GH/IGF-I axis influences gonadal development and function. Recently, a deletion of exon 3 in the GH receptor gene (GHRd3) has been linked to increased responsiveness to GH.

The aim of this study was to investigate endothelial lipase (EL, LIPG) and lipoprotein lipase (LPL) mRNA and protein expression in normal human testis and testicular germ cell tumours (GCT). Both EL and LPL were expressed in normal seminiferous tubules and in the interstitial compartment. EL mRNA and protein were found in all germ cells as well as in Sertoli and Leydig cells. EL mRNA was abundant in pre-invasive carcinoma in situ (CIS) cells and GCTs, and EL protein was present in the cytoplasm of these cells. LPL mRNA was also relatively abundant in germ cells, Sertoli cells, CIS cells and GCTs. The LPL protein, however, was restricted to the cell membranes of pachytene spermatocytes and spermatids in normal tubules, absent from CIS cells and scarcely represented in tumours. The distribution of LPL protein in non-seminomas resembled the distribution of OCT3/4, a marker of embryonal carcinoma. The results suggest that both EL and LPL participate in the supply of nutrients and steroidogenesis in the testes, and that especially EL may be important for the supply of cholesterol for testosterone production in the Leydig cells. The partial cellular separation of the expression of the two lipases in normal testis suggests the existence of distinct biological roles, perhaps developmentally regulated, as indicated by the LPL expression in GCTs with embryonic features. A high expression of EL and abundance of lipid in tubules with CIS may have a diagnostic value.

Udgivelsesdato: 2008-Nov, BACKGROUND: A possible association between the polymorphic CAG repeat in the DNA polymerase gamma (POLG) gene and the risk of testicular germ-cell tumours (TGCT) was investigated in this study. The hypothesis was prompted by an earlier preliminary study proposing an association of the absence of the common 10-CAG-long POLG allele with testicular cancer as well as previously reported in some European populations' association with male subfertility, which is a condition carrying an increased risk of TGCT. PATIENTS AND METHODS: The number of CAG repeats in both POLG alleles was established in 243 patients with TGCT and in 869 controls by the analysis of the genomic DNA fragment. RESULTS: A significantly higher proportion of men homozygous allele of other than the common 10 CAG repeats was found among the patients with TGCT in comparison to the controls (4.9% versus 1.3%, respectively, P = 0.001). The vast majority of the homozygous patients had a seminoma (11 of 12; 97%), despite that only about half (55%) of the studied patients had this tumour type. CONCLUSIONS: The findings indicate that the POLG polymorphism may be a contributing factor in the pathogenesis of TGCT particularly in seminoma, but the mechanisms remain to be elucidated.

Healthy men produce an enormous number of sperms, far more than necessary for conception. However, several studies suggest that semen samples where the concentration of sperms is below 40 mill/mL may be associated with longer time to pregnancy or even subfertility, and specimens where the concentration of sperms is below 15 mill/mL may carry a high risk of infertility. Historic data from the 1940s show that the bulk of young men at that time had sperm counts far above 40 mill/mL with averages higher than 100 mill/mL. However, recent surveillance studies of young men from the general populations of young men in Northern Europe show that semen quality is much poorer. In Denmark approximately 40 percent of the men have now sperm counts below 40 mill/mL. A simulation assuming that average sperm count had declined from 100 mill/mL in 'old times' to a current level close to 40 mill/mL indicated that the first decline in average sperm number of 20-40 mill/mL might not have had much effect on pregnancy rates, as the majority of men would still have had counts far above the threshold value. However, due to the assumed decline in semen quality, the sperm counts of the majority of 20 year old European men are now so low that we may be close to the crucial tipping point of 40 mill/mL spermatozoa. Consequently, we must face the possibility of more infertile couples and lower fertility rates in the future.

BACKGROUND: UTF-1 and REX-1/ZFP42 are transcription factors involved in pluripotency. Because of phenotypic similarities between pluripotent embryonic stem cells and testicular germ cell tumours (TGCT) and the derivation of pluripotent cells from testes, we investigated the expression of UTF-1 and REX-1 during human gonadal development and in TGCT. METHODS: Expression of UTF-1 and REX-1 was studied in 52 specimens from human gonadal development and in 86 samples from TGCT. RESULTS: UTF-1 and REX-1 were expressed throughout male gonadal development. In the mature testis, UTF-1 was expressed in spermatogonia, whereas REX-1 was expressed in meiotic cells and, together with OCT-3/4, in primary oocytes. Both UTF-1 and REX-1 were expressed in testicular carcinoma in situ and in TGCT. Contrarily to REX-1, UTF-1 was expressed in all spermatocytic seminomas. CONCLUSIONS: Unlike other pluripotency markers NANOG and OCT-3/4, UTF-1 and REX-1 are expressed throughout human testes development. The expression pattern indicated that UTF-1 plays a possible role in spermatogonial self-renewal, whereas expression of REX-1 in meiotic cells from both testes and ovary indicate a role in meiosis. UFT-1 and REX-1 are expressed in TGCT and the high abundance of UTF-1 in spermatocytic seminomas is consistent with the hypothesis that this tumour type originates from spermatogonia Udgivelsesdato: 2008/4

Chlormequat is a plant growth regulator widely used on cereals, and there is general concern that it may impair human fertility. A LC-MS/MS method for the analysis of chlormequat in milk and serum was developed and validated in connection with an investigation on the effect of chlormequat on pig reproduction. Validation of the method was based on recovery tests at three spiking levels, determined as double determinations and repeated at least four times. Samples were extracted with methanol-water-acetic acid, centrifuged, filtrated and determined by LC-MS/MS. The mean recoveries were in the range 80-110%, and the LOD was 0.2 ng/g for serum and 0.3 ng/g for milk. The values for repeatability and reproducibility were within 2/3 of the limits given by the Horwitz equation. Samples of pig serum (59) and sow milk (27) were analyzed using the method. Chlormequat was determined in four milk samples in the range of 0.4 ng/g to 1.2 ng/g and in all serum samples in the range of 0.2 ng/g-4.0 ng/g.

Recently a worldwide rise in the incidence of testicular germ cell cancer (TGCC) has been repeatedly reported. The changing disease pattern may signal that other testicular problems may also be increasing. We have reviewed recent research progress, in particular evidence gathered in the Nordic countries, which shows strong associations between testicular cancer, undescended testis, hypospadias, poor testicular development and function, and male infertility. These studies have led us to suggest the existence of a testicular dysgenesis syndrome (TDS), of which TGCC, undescended testis, hypospadias/disorders of sex differentiation and male fertility problems may be symptoms with varying penetration. In spite of their fetal origin, most of the TDS symptoms, including TGCC and poor semen quality, can only be diagnosed in adulthood. Data from a Danish-Finnish research collaboration strongly suggest that trends in TGCC rates of a population may be 'whistle blowers' of other reproductive health problems. As cancer registries are often of excellent quality - in contrast to registries for congenital abnormalities - health authorities should consider an increase in TGCC as a warning that other reproductive health problems may also be rising.

Udgivelsesdato: 2007-Apr