Although it is established that in utero exposure to antiandrogenic compounds such as flutamide induces hypospermatogenesis in adult male rat offspring, the cellular and molecular mechanisms remain to be investigated. By using adult rats exposed in utero to flutamide (0.4, 2, 10 mg/kg.d) as a model, we show that the hypospermatogenesis could be related to a chronic apoptotic cell death process associated with a long-term increase in caspase-3 and -6 expression and activation in germ cells. The number of apoptotic (terminal deoxynucleotidyl transferase-mediated deoxyuridine positive) adult germ cells was dependent on the dose of flutamide. The apoptotic germ cell death process could be related to an increased expression and activation of effector caspases-3 and -6. Procaspases-3 and -6 were immunodetected in germ cells from both untreated or flutamide-treated rats, whereas cleaved active caspase-3 was detected exclusively in germ cells from adult rat exposed in utero to flutamide. Exposure to the antiandrogen increased in a dose-dependent manner as caspase-3 and -6 mRNA (in RT-PCR approaches) as well as procaspase-3 and -6 protein (in Western blotting analyses) levels in the adult rat testis. Flutamide also activates procaspases. Indeed, whereas cleaved active caspase-3 and -6 proteins were absent in control animals, they were detected in adult rat testes exposed in utero to flutamide. Our results show that whereas the apoptotic germ cell death process associated with the increased caspase expression and activation in adult rat germ cells was chronic and nonreversible when exposure to flutamide occurred in utero, it was transient when such an exposure occurred during adulthood. Indeed, although an increase in caspase-3 and -6 mRNA and procaspase-3 and -6 protein levels was observed in germ cells after 3 d of exposure to flutamide, 1-2 wk after the cessation of the antiandrogen exposure, the caspase mRNA and procaspase protein levels were back to control. Active cleaved caspase-3 and -6 protein appeared following the exposure to the antiandrogen, whereas they disappeared at cessation of exposure to flutamide. In summary, the present findings indicate that in utero exposure to the antiandrogen induced in the adult rat testes a chronic apoptotic germ cell death associated with a long-term increase in the expression and activation in germ cells of caspases-3 and -6, two key components in the death machinery.

In the present study we investigated whether fetal exposure to flutamide affected messenger and protein levels of claudin-11, a key Sertoli cell factor in the establishment of the hemotesticular barrier, at the time of two key events of postnatal testis development: 1) before puberty (postnatal d 14) during the establishment of the hemotesticular barrier, and 2) at the adult age (postnatal d 90) at the time of full spermatogenesis. The data obtained show that claudin-11 expression was inhibited in prepubertal rat testes exposed in utero to 2 and 10 mg/kg x d flutamide. However, in adult testes, the inhibition was observed only with 2, and not with 10, mg/kg x d of the antiandrogen. It is shown here that these differences between prepubertal and adult testes could be related to dual and opposed regulation of claudin-11 expression resulting from positive control by androgens and an inhibitory effect of postmeiotic germ cells. Indeed, testosterone is shown to stimulate claudin-11 expression in cultured Sertoli cells in a dose- and time-dependent manner (maximum effect with 0.06 microm after 72 h of treatment). In contrast, postmeiotic germ cells potentially exert a negative effect on claudin-11 expression, because adult rat testes depleted in spermatids (after local irradiation) displayed increased claudin-11 expression, whereas in a model of cocultured Sertoli and germ cells, spermatids, but not spermatocytes, inhibited claudin-11 expression. The apparent absence of claudin-11 expression changes in adult rat testes exposed to 10 mg/kg x d flutamide therefore could result from the antagonistic effects of 1) the inhibitory action of the antiandrogen and 2) the stimulatory effect of the apoptotic germ cells on claudin-11 expression. Together, due to the key role of claudin-11 in the hemotesticular barrier, the present findings suggest that such regulatory mechanisms may potentially affect this barrier (re)modeling during spermatogenesis.

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Patients with cancer are at higher risk of severe coronavirus infectious disease 2019 (COVID-19), but the mechanisms underlying virus–host interactions during cancer therapies remain elusive. When comparing nasopharyngeal swabs from cancer and noncancer patients for RT-qPCR cycle thresholds measuring acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in 1063 patients (58% with cancer), we found that malignant disease favors the magnitude and duration of viral RNA shedding concomitant with prolonged serum elevations of type 1 IFN that anticorrelated with anti-RBD IgG antibodies. Cancer patients with a prolonged SARS-CoV-2 RNA detection exhibited the typical immunopathology of severe COVID-19 at the early phase of infection including circulation of immature neutrophils, depletion of nonconventional monocytes, and a general lymphopenia that, however, was accompanied by a rise in plasmablasts, activated follicular T-helper cells, and non-naive Granzyme B+FasL+, EomeshighTCF-1high, PD-1+CD8+ Tc1 cells. Virus-induced lymphopenia worsened cancer-associated lymphocyte loss, and low lymphocyte counts correlated with chronic SARS-CoV-2 RNA shedding, COVID-19 severity, and a higher risk of cancer-related death in the first and second surge of the pandemic. Lymphocyte loss correlated with significant changes in metabolites from the polyamine and biliary salt pathways as well as increased blood DNA from Enterobacteriaceae and Micrococcaceae gut family members in long-term viral carriers. We surmise that cancer therapies may exacerbate the paradoxical association between lymphopenia and COVID-19-related immunopathology, and that the prevention of COVID-19-induced lymphocyte loss may reduce cancer-associated death.

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Recently, we and others have described a novel class of chromosome aberrations that involves constitutive heterochromatin on human chromosome 1 (cytogenetic band 1q12). These anomalies are particularly frequent in B cell non-Hodgkins lymphoma (NHL) and multiple myeloma (MM) and, remarkably, almost invariably involve partial or total gain of chromosome 1q (including 1q12 heterochromatin) and the formation of novel heterochromatin/euchromatin junctions. This review discusses the pathological significance of these anomalies in light of i) recent integrated gene expression and array comparative genomic hybridisation (aCGH) profiling in MM and ii) increasing evidence of a key role for heterochromatin in the control of normal and pathological gene silencing.

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Fetal androgen disruption, induced by the administration of anti-androgen flutamide (0 . 4, 2, and 10 mg/kg day) causes a long-term apoptosis in testicular germ cells in adult male rat offspring. One of the questions raised by this observation is the role of the Sertoli cells in the adult germ cell apoptotic process. It is shown here that Sertoli cells originating from 15-day-old rats treated in utero with the anti-androgen (10 mg/kg d) did no longer protect adult germ cells against apoptosis. Indeed, untreated spermatocytes or spermatids exhibited increased (P!0 . 0001) active caspase-3 levels when co-cultured with Sertoli cells isolated from rat testes exposed in utero to the anti-androgen. This alteration of Sertoli cell functions was not due to modifications in the androgen signal in the adult (90-day-old) animals, since plasma testosterone and estradiol, androgen receptor expression, and androgentargeted cell number (e.g., Sertoli cells in the seminiferous tubules) were not affected by the fetal androgen disruption. In contrast, this inability of Sertoli cells to protect germ cells against apoptosis could be accounted for by the potential failure of Sertoli cell functions. Indeed, adult testes exposed in utero to anti-androgens displayed decreased levels of several genes mainly expressed in adult Sertoli cells (anti-Mullerian hormone receptor type II (AMHR2), Cox-1, cyclin D2, cathepsin L, and GSTa). In conclusion, fetal androgen disruption may induce alterations of Sertoli cell activity probably related to Sertoli cell maturation, which potentially leads to increased adult germ cell apoptosis.