Gloria Queipo

Participation of OCT3/4 and β-catenin during dysgenetic gonadal malignant transformation

Gonadoblastoma (GB) is an in situ tumor consisting of a heterogeneous population of mature and immature germ cells, other cells resembling immature Sertoli/granulosa cells, and Leydig/lutein-like cells, may also be present. GB almost exclusively affects a subset of patients with intersex disorders and in 30% of them overgrowth of the germinal component of the tumor is observed and the lesion is term dysgerminoma/seminoma. Several pathways have been proposed to explain the malignant process, and abnormal OCT3/4 expression is the most robust risk factor for malignant transformation. Some authors have suggested that OCT3/4 and beta-catenin might both be involved in the same oncogenic pathway, as both genes are master regulators of cell differentiation and, overexpression of either gene may result in cancer development. The mechanism by which beta-catenin participates in GB transformation is not completely clear and exploration of the E-cadherin pathway did not conclusively show that this pathway participated in the molecular pathogenesis of GB. Here we analyze seven patients with mixed gonadal dysgenesis and GB, in an effort to elucidate the participation of beta-catenin and E-cadherin, as well as OCT3/4, in the oncogenic pathways involved in the transformation of GB into seminoma/dysgerminoma. We conclude that the proliferation of immature germ cells in GB may be due to an interaction between OCT3/4 and accumulated beta-catenin in the nuclei of the immature germ cells.

Loss of Cytochrome P450 17A1 Protein Expression in a 17α-Hydroxylase/17,20-Lyase-Deficient 46,XY Female Caused by Two Novel Mutations in the CYP17A1 Gene

Abstract17α-Hydroxylase deficiency (17OHD) is a rare form of congenital adrenal hyperplasia caused by mutations in the CYP17A1 gene. This condition shows considerable clinical and biochemical variation. Molecular characterization of novel mutations in the CYP17A1 gene and detailed study of their structural, enzymatic, and clinical consequences are required to fully understand enzyme behavior. Here, we present the first molecular characterization of two novel mutations in CYP17A1 in a 15-year-old female Mexican mestizo 46,XY female with primary amenorrhea and lack of pubertal development and severe hypertension that manifested only after surgery. A complete clinical and biochemical evaluation was compatible with 17OHD. Structural anomalies in the CYP17A1 gene were discovered by direct automated sequencing, which revealed a novel compound heterozygous K110X/R362H mutation that leads to a complete lack of enzyme activity. Immunohistochemical analyses performed to determine protein expression and localization showed that cytochrome P450 17A1 was completely absent in the patient’s testicular tissue. Studies of novel mutations, such as those described here, provide important information that allows us to better understand the effect of a given mutation on enzyme function and to observe the impact of the mutation on clinical phenotype.

The high frequency of genetic diseases in hypotonic infants referred by neuropediatrics

Neonatal hypotonia is a relatively common cause of consultation in daily pediatric practice. It is part of the clinical presentation of a large group of heterogeneous diseases, many of which have an important and classifiable genetic background. Identification of the specific disorder can help optimize the management and treatment of the patient and inform genetic counseling for the family, and therefore input from clinical geneticists is critical at the earliest stages of medical management. Here we present 30 patients with hypotonia of unknown etiology referred by a neuropediatrician to clinical genetics. Clinical, genetic, and molecular evaluation of each patient was performed. Sixty‐nine percent of the patients included in the study had a genetic disease, including eight with Prader–Willi syndrome, three with spinal muscular atrophy, one with Rett syndrome, and one with Sotos syndrome harboring a previously undescribed mutation. Our data demonstrate that a multidisciplinary approach used from the outset that includes molecular analysis can help improve diagnosis and management of hypotonic infants.

Mix Gonadal Dysgenesis Associated with Ring Y Chromosome Mosaics in a Phenotypic Male

Ring chromosomes are present in 1 in 25,000 human fetuses; 99% arise de novo while less than 1% of rings are inherited. This chromosomal rearrangement may arise through a cytogenetic mechanism involving breaks in chromosome arms and fusion of the proximal broken ends, leading to a loss of distal material. Most patient Y ring chromosomes are present in a 45,X/46,X,r(Y) mosaic karyotype; molecular analyses of infertile men have shown that it is not rare to find r(Y) in these patients. However, the clinical spectrum in those cases with a 45,X cell line is broad and depends on the percentage of the monosomic cell line in different tissues. Y chromosome abnormalities and 45,X mosaic karyotypes are often associated with disorders of sex determination. Here, we report a male patient with hypospadias, cryptorchidism and a mosaic karyotype containing a low proportion of 45,X monosomic cells and multiple ring Y chromosomes in peripheral blood. Clinical, surgical, and molecular evidence was sufficient for a diagnosis of mixed gonadal dysgenesis. We suggest that a detailed cytogenetic and molecular analysis should be done in all males with bilateral descended testes and infertility.

Physical Activity Protects Men but Not Women for Sarcopenia Development

Objective: Sarcopenia is among the most deleterious effects of aging. The objective of this study was to analyze the relationship between performance tests and muscular volume over the life span of male and female participants. Method: A correlation study was conducted with healthy individuals (50 males and 47 females) between the ages of 20 and 94; the study group included active older people, sedentary younger people, and young athletes. Muscular volume was determined by tomography and muscular performance (4-meter speed tests [4 MSTs], chair test, and handgrip test), and a correlation analysis between the groups was performed. Results: Sex-related differences were observed between the variables; in males, muscle volume and functional parameters were closely related with age and physical activity, whereas in females, they were not related at all. Conclusion: Male and female muscle volume and performance demonstrate strong differences, which should be considered during clinical evaluations of sarcopenia.

Case Reports Muscular Volume or Fatigue: Which Is the Most Important Feature for the Evaluation of Muscular Performance in Elderly Adults?

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Peripheral Blood Regulatory T Cells Are Diminished in Kidney-Transplant Patients with Chronic Allograft Nephropathy

Introduction Kidney transplantation (KT) remains the major life-saving treatment for patients with end-stage renal disease. Despite the improvements in immunosuppressive strategies in recent years, late kidney allograft loss is a critical clinical challenge for long-term graft survival Over the past two decades, immunosuppressive drugs have failed to produce substantial long-term graft survival. Kidney allograft recipients, especially those individuals receiving organs from deceased donors, frequently suffer from the slow deterioration of kidney function or chronic allograft nephropathy (CAN). However, defining CAN as an idiopathic and multifactorial entity has precluded more comprehensive studies. Abundant evidence from animal models, as well as limited evidence from humans, involves Tregs in kidney transplant tolerance, although the recognition of allo or self-antigens by Tregs is not clear. Objective Investigate the peripheral blood levels of CD4+CD25+FOXP3p3+ regulatory T cells (Tregs) in patients with chronic allograft nephropathy (CAN) one year after kidney transplantation and compare it with chronic disease undergo hemodialysis and healthy controls. Methods Twelve renal-transplant patients with an initial onset of CAN, 12 patients with chronic kidney disease (CKD) stage G5 on dialysis, and 13 healthy control individuals were evaluated regarding the proportion of Tregs in their peripheral blood via flow cytometry. Results The renal-transplant patients with CAN had a significantly lower proportion of Tregs than the hemodialysis-CKD patients and healthy controls (P<0.01). In contrast, the hemodialysis-CKD patients showed higher levels of Tregs than the renal-transplant patients with CAN and the healthy controls (P<0.01) Figure 1 Figure. No caption available. Conclusion The high level of peripheral blood Tregs in the hemodialysis-CKD patients suggests a chronic inflammatory state. However, the low frequency of Tregs in the peripheral blood from the renal-transplant patients with CAN suggests an unfavorable prognosis for allograft immune tolerance. In representation of the work team I would like to state, that there are no known conflicts of interest associated with these work and there has been no significant financial support for this work that could have influenced its outcome.

Overexpression of BAX, NOL3, and XIAP Apoptotic Genes Participates in Calcineurin Inhibitors Nephrotoxicity: New Insights into Chronic Allograft Dysfunction

Introduction Calcineurin inhibitors (CNI) remain the most effective and widely used immunosuppressive agents in organ transplantation, is a factor that limit the outcome of renal transplantation graft rejection. Renal biopsy remains the best method for identifying nephrotoxicity. The hypoxia causes histological data as nodular hyalinosis, hyalinosis, fibrosis, thrombotic microangiopathy, and isometric tubular vacuolization. The diagnosis requires an invasive procedure, an expert pathologist, but more importantly: it is an exclusion diagnosis. Aim Exploratory and descriptive study of the gene expression behavior of representative extrinsic and intrinsic apoptotic pathways in renal biopsies of 5 patients with CNIT where compare with biopsies without toxicity data. Subjects and Methods An Observational, descriptive cross sectional study was conducted. A convenience size of 7 renal biopsies samples was included from the Organ Transplant Unit of the Hospital General de México from January to March 2017. 5 correspond to transplanted patients with clinical, biochemical or histopathological data of calcineurin-inhibitors toxicity (CNIT). The mRNA expression of renal tissue biopsies was analyzed using the RT2 Profiler PCR Array platform considering genes involved processes associated with renal damage. Results Two of five patients presented acute renal dysfunction with clinical and biochemical data with creatinine values of 2.5 mg/dl and CNIT values before the biopsy of 16ng/ml and 21 mg/ml respectively. The rest of the cases the toxicity was an incidental finding in the year follow up biopsy during the histopathological analysis. The expression analyses of the genes associated directly with the inflammatory process (interleukins 2, 4, 6, 8, 10, TNF alpha, and TNF beta) showed in all the cases and also in the controls the absence of any detectable transcript in all the cytokines studied. Interesting was that in all the samples an undetectable value was obtained, not even basal expression compared with the constitutive gene. The QPCR arrays showed that Bcl-2-associated X protein (BAX), Nucleolar Protein 3 (NOL3) and X-Linked Inhibitor of Apoptosis (XIAP) were consistent only in the CNIT patients. The Mann-Whitney U test was consistent for the three evaluated genes revealed in the control group an average rank of 1.5, while the patients have three more times with respect the control. This result suggests that in the group of patients with CNIT BAX is activated, this gene is a key player in the intrinsic apoptosis pathway, suggesting that apoptosis via mitochondria is turn on probably due to the arteriolar vasoconstriction and the hypoxic state. Figure. No caption available. Figure. No caption available. Conclusions We proposed that intrinsic apoptotic pathway plays a relevant role in the physiopathology of the CNIT. In representation of the work team I would like to state, that there are no known conflicts of interest associated with this work.

Analysis of PTPN22, ZFAT and MYO9B polymorphisms in Turner Syndrome and risk of autoimmune disease

Turner syndrome (TS) is one of the most common sexual chromosome abnormalities and is clearly associated with an increased risk of autoimmune diseases, particularly thyroid disease and coeliac disease (CD). Single‐nucleotide polymorphism analyses have been shown to provide correlative evidence that specific genes are associated with autoimmune disease. Our aim was to study the functional polymorphic variants of PTPN22 and ZFAT in relation to thyroid disease and those of MYO9B in relation to CD. A cross‐sectional comparative analysis was performed on Mexican mestizo patients with TS and age‐matched healthy females. Our data showed that PTPN22 C1858T (considered a risk variant) is not associated with TS (X2 = 3.50, p = .61, and OR = 0.33 [95% CI = 0.10–1.10]). Also, ZFAT was not associated with TS (X2 = 1.2, p = .28, and OR = 1.22 [95% CI = 0.84–1.79]). However, for the first time, rs2305767 MYO9B was revealed to have a strong association with TS (X2 = 58.6, p = .0001, and OR = 10.44 [95% C = 5.51–19.80]), supporting a high level of predisposition to CD among TS patients. This report addresses additional data regarding the polymorphic variants associated with autoimmune disease, one of the most common complications in TS.

New Genetic Abnormalities in Non-21α-Hydroxylase-Deficiency Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia comprises a group of autosomal recessive disorders of sexual differentiation and development that occur due to deficiencies in steroidogenic enzymes within the adrenal gland. Using clinical, biochemical, and sequencing data, we describe non-21α-hydroxylase deficiencies in 6 individuals from 4 families originating from endogamic regions in Mexico. Three individuals had 11β- hydroxylase deficiencies caused by 2 hitherto unreported mutations (P442L substitution and an 11-bp insertion in exon 5 of CYP11B1), while 3 individuals had 17α-hydroxylase/17,20-lyase deficiencies. Sequence-tagged site analysis of 8 individuals from 1 endogamic region suggested that the mutations likely occurred as a result of a founder effect. Although non-21α-hydroxylase enzymatic defects are rare in most populations, characterization of new mutations is important in order to understand the demographic, clinical, biochemical, and molecular variations that exist, and for both active and preventative management in individuals and their communities.