Surveillance of human papilloma virus infection and cervical cancer in kidney transplant recipients: preliminary data.

INTRODUCTION: Development of cancer after transplantation has rapidly became one of the leading causes of death in kidney transplant recipients with functioning grafts. Anogenital malignant neoplasms may occur with a 14-fold increased incidence, and human papilloma virus (HPV) infection has been recently identified as the leading cause of cervical carcinoma. We report the preliminary findings of a prospective study that evaluated the incidence of HPV infection and cervical carcinoma in a population of kidney transplant recipients. PATIENTS AND METHODS: The study included 35 female recipients of a deceased donor kidney with at least 6 months of follow-up. All patients underwent a cervicovaginal brushing, an HPV DNA test, and a Papanicolaou test. RESULTS: Twenty-two patients (62.8%) were positive for HPV DNA. Thirteen of 22 HPV DNA-positive recipients (59%) demonstrated a high-risk HPV genotype. No cytologic anomalies were detected in Papanicolaou smears. CONCLUSIONS: These preliminary data demonstrated a high incidence of HPV infection in renal transplant recipients. Most of our recipients exhibited a high-risk HPV genotype, which suggests higher aggressiveness of such infection in immunosuppressed patients. The HPV test is useful to monitor patients at higher risk of anogenital malignant neoplasms by identifying the cytologic anomalies at an earlier stage. This ongoing study will investigate the rate of progression of HPV infection and the clinical patterns of HPV-positive cytologic anomalies in renal transplant recipients.

Corticotrophin-releasing hormone inhibits insulin-like growth factor-I release from primary cultures of rat granulosa cells.

Corticotrophin-releasing hormone (CRH), a neuropeptide which modulates gonadal function during stress, is expressed by several cell types of the rat ovary and is able to suppress oestrogen release from rat granulosa cells. The mechanism of this effect is, however, not known. Since insulin-like growth factor (IGF)-I is produced by rat granulosa cells and exerts a synergistic role with FSH on granulosa cell steroidogenesis, we hypothesised that CRH may suppress oestrogen release from granulosa cells by inhibiting IGF-I release and/or stimulating the release of its binding protein (IGFBP-3). To test this hypothesis, granulosa cells were obtained from immature female Sprague-Dawley rats primed with diethylstilboestrol, and hormone concentrations were measured in the conditioned medium by radioimmunoassay. CRH suppressed oestrogen and IGF-I release stimulated by FSH used at a concentration of 1 IU/l, whereas it did not have any statistically significant effect on oestrogen and IGF-I release in basal conditions or in response to 5 IU/l FSH. The suppressive effects of CRH on oestrogen and IGF-I release were antagonised by a selective CRH receptor antagonist. CRH had no effects on IGFBP-3 release. CRH did not have any effect on oestrogen release stimulated by increasing concentrations of IGF-I and its suppressive effect on FSH-stimulated oestrogen release was overcome by the addition of low doses of exogenous IGF-I. In conclusion, CRH suppressed the release of oestrogen and IGF-I, but not of IGFBP-3. Thus, the inhibitory effects of CRH on oestrogen release could be mediated, partly, by a suppression of the autocrine/paracrine action of IGF-I.

High sperm aneuploidy rate in unselected infertile patients and its relationship with intracytoplasmic sperm injection outcome.

BACKGROUND: Men with oligoasthenoteratozoospermia (OAT) frequently undergo intracytoplasmic sperm injection (ICSI) as a treatment for their infertility. However, there is an increased risk of transmitting chromosomal abnormalities to the offspring given that natural selection is bypassed by the use of this technique and patients have an increased rate of sperm aneuploidy which, in addition, may negatively affect ICSI outcome. For this reason, the rate of sperm aneuploidy in unselected patients undergoing ICSI and its impact on ICSI performance have been evaluated. METHODS: Aneuploidy and diploidy were evaluated in spermatozoa separated by swim-up for oocyte injection, using DNA probes for chromosomes 8, 12, 18, X and Y. RESULTS: ICSI patients had sperm aneuploidy and diploidy rates significantly higher than those of 13 normozoospermic men who served as controls. Although the total aneuploidy rate varied considerably between the 18 patients, 15 of them (83%) had values above the upper range of the control group. Eighteen ICSI cycles were performed with an overall fertilization rate of 95% and a pregnancy rate of 39%. The aneuploidy rate of the 11 patients whose wives did not achieve pregnancy was slightly higher than that of pregnant couples, but the difference did not reach statistical significance. However, 10 patients in this group (91%) had a sperm aneuploidy rate well above the upper limit of the controls as compared with two patients in the "pregnant" group (29%). CONCLUSIONS: This study has shown that unselected patients undergoing ICSI had an elevated sperm aneuploidy rate. Lack of pregnancy was associated with a tendency towards an increased aneuploidy rate; however, pregnancy occurred even in the presence of an elevated sperm aneuploidy rate.

Cloning and expression of activator of CREM in testis in human testicular tissue.

Activator of cAMP-responsive element modulator (CREM) in testis (ACT) has recently been found in the mouse testis where it activates CREM, a transcription factor essential for the differentiation of spermatids into mature spermatozoa. The importance of CREM in human spermatogenesis prompted us to examine whether ACT was also present in the human testis. Western blot analysis, performed with an anti-mouse ACT serum, showed the presence of a single immunoreactive band of a size similar to murine ACT. A library screening resulted in the isolation and characterization of the complete cDNA which showed 88% homology with the mouse counterpart. The human ACT gene is composed of five coding exons, being the first untranslated, and the mRNA spans 835 nucleotides coding for a 284 amino acid protein. Expression studies by RT-PCR confirmed that ACT is present in normal human testis. The human ACT gene is localized on the chromosome 6.

Effects of cancer and anti-neoplastic treatment on the human testicular function.

Men with testicular neoplasia (TN) and Hodgkin's disease (HD) are those who more frequently require treatment for fertility because these malignancies affect patients during the reproductive age and because the early diagnosis and the improved anti-neoplastic treatments cure most of these patients. Although some of them can father a child spontaneously, assisted reproductive techniques allow fatherhood to patients with severe spermatogenesis impairment and this possibility has raised concern about the long-term consequence of the testicular damage induced by chemo- and/or radiotherapy. This paper reviews the effects of cancer per se and of anti-neoplastic treatments on gonadal function, sperm aneuploidy rate and sperm DNA integrity. A debate is still open as to whether TN or HD per se may impair spermatogenesis. Many studies have shown that this is the case, albeit others have challenged this view. Chemo- and/or radiotherapy affects negatively gonadal function, rendering almost all patients azoospermics. However, spontaneous pregnancies and a high degree of spermatogenesis recovery occur with time. A large body of literature on sperm chromosome complement suggests an increased rate of structural and numerical chromosome abnormalities in patients with cancer during anti-neoplastic treatment. A minority of them has, however, shown that this effect disappears with time. An interesting and relatively new aspect is the study of sperm DNA integrity in patients with TN and HD particularly following chemo- and/or radiotherapy. The scanty information available seems to suggest that these patients have a permanent or at least a long-lasting DNA fragmentation in their spermatozoa.

Effects of progesterone on sperm function: mechanisms of action.

Progesterone stimulates sperm functions, e.g. hyperactivation, acrosome reaction, binding to oocyte zona pellucida and penetration rate into the hamster oocyte. The physiological relevance of these effects has been shown using female genital tract fluids which modulate sperm function according to their progesterone content. Progesterone interacts with specific sperm binding sites that, unlike the classic nuclear receptors, are located on the plasma membrane of the spermatozoon. Binding studies have revealed the presence of two classes of progesterone receptors in the human spermatozoon, one class has an elevated affinity constant (nanomolar) and is specific for progesterone, whereas the other class has an affinity constant in the micromolar range and binds equally well other hydroxylated progesterone derivatives. Following exposure to progesterone, the main event is a rapid (within seconds) increase of the intracellular free calcium concentration, followed by a sustained rise lasting for several minutes (plateau phase). Both these calcium transients are dependent upon entry of extracellular calcium. The nature of the calcium channel that mediates the effects of progesterone is, currently, unknown. It has been postulated that it may be: (i) part of the progesterone receptor; (ii) voltage-dependent; or (iii) operated by second messengers following activation of the progesterone receptor. Progesterone also modulates sperm function by stimulating a trypsin-like proteolytic activity, the biosynthesis of polyamine (putrescine and spermidine), phospholipase A2 activity and protein tyrosine kinase activity in the sperm cell. Recent studies have shown that chloride ion efflux is vital for progesterone to promote the acrosome reaction. This effect is achieved by interaction with a sperm membrane receptor which resembles the neuronal GABA(A) receptor. Accordingly, GABA(A) receptors have been found in the spermatozoon plasma membrane and GABA stimulates hyperactivation and promotes the acrosome reaction.

Intracytoplasmic injection of round and elongated spermatids from azoospermic patients: results and review.

Microinjection is established as the method of choice in the treatment of severe male factor infertility as well as in azoospermic patients. Recent studies have shown that fertilization and cleavage can be achieved by injection of ejaculated as well as testicular elongated spermatids into oocytes. Here we report on the two first pregnancies worldwide resulting from elongated spermatid injection from frozen-thawed testicular tissue. Four patients with complete Sertoli cell-only syndrome (SCOS) and two with spermatogenetic maturation arrest were included in our microinjection programme. Tissues from open testicular biopsies were cryopreserved until the time of follicle puncture. A total of 67 oocytes were harvested. In the two patients with maturation arrest, cryopreserved elongated spermatids were successfully injected, while in two of the other four SCOS patients only cryopreserved round spermatids were available to be injected into the oocytes. Out of 18 injected oocytes, 10 were fertilized in the first group, while nine out of 49 injected oocytes showed fertilization and cleavage in the second group. Two clinical pregnancies were achieved with elongated spermatids from frozen-thawed testicular tissue, while no pregnancy was established in the case of round spermatids. This study confirms that fertilization, cleavage and pregnancy can be successfully achieved in cases with spermatogenetic maturation arrest by injecting cryopreserved elongated spermatids into oocytes. The literature on pregnancies following spermatid injection, as well as the problems using this technique and possible risks, are discussed.