Abstract P2-13-01: The Brazilian founder TP53 p.R337H mutation is uncommon in Portuguese women diagnosed with breast cancer

Since the first studies reporting the TP53 p.R337H mutation as founder mutation in Southern and Southeastern regions of Brazil, both in the general population and in patients from high risk breast cancer families with adrenocortical, choroid plexus and breast carcinomas, there has been controversy on the origin of this mutation. Preliminary analysis of the small subset of Brazilian mutation carriers that defined the founder haplotype using 29 tag SNPs revealed that the haplotype incided on a Caucasian background. The vast majority of carriers identified today reside in Brazil or, if identified in other countries, are Brazilian immigrants. To our knowledge, the only two exceptions of carriers without a recognizable link with Brazil are two European families (one Portuguese and one German) (Chompret et al., 2000; Herrmann et al. 2012). Haplotype analysis in the Portuguese family revealed the same haplotype identified in Brazilian individuals, but in the German family, a distinct haplotype was found. Knowing that a significant proportion of women with breast cancer in Southern Brazil are p.R337H carriers, we initiated TP53 genotyping in a Portuguese cohort of women with breast cancer recruited from the cities of Lisboa and Braga. Median age at diagnosis of breast cancer among the first 573 patients tested was 60 years and 100 (17.4%) patients had been diagnosed at or under the age of 45 years. Mutation screening was performed using Real-Time PCR (taqman assays), and failed to identify the mutation in the 573 patients tested. These results are in contrast with the mutation frequency observed in a study of 815 breast cancer-affected women from Southern and Southeastern Brazil, which has reached frequencies of 12.1 and 5.1% in pre- and post-menopausal women, respectively (Ashton-Prolla et al. 2012; ASCO Annual Meeting, ref 1522). We conclude that there is a significant difference in mutation frequency observed between the two cohorts (p<0.001). These findings suggest that TP53 p.R337H is not a common molecular alteration in Portuguese breast cancer-affected patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-13-01.

Complicações da Transplantação Renal em Idade Pediátrica

Background: Renal transplantation is the treatment of choice for children with end stage renal disease with positive impact on survival and quality of life. However, some complications affect morbidity and mortality. This study examines the renal transplantation complications profile in pediatric patients (< 18 y).Material and Methods: Retrospective analysis of clinical files from renal transplantation patients followed in Pediatric Nephrology Unit from September 1995 to August 2010. Collection of data regarding: demography, end stage renal disease etiology, previous renal replacement therapy, graft loss and death, complications: surgical, infectious and non-infectious (acute and chronic rejection, primary disease recurrence, metabolic and cardiovascular risk factors). Descriptive statistical analysis was performed.Results: 78 children (male: 48.7%), mean age at renal transplantation: 11.7 4.1 years. Previous peritoneal dialysis in 49 (62.6%). Five patients (6.4%) with preemptive renal transplantation. Median follow up: 37.5 months (1 - 169). Main end stage renal disease etiologies were urologic conditions in 41% and glomerular disease in 28.2%. Infectious complications occurred in 74%: viral: 56.4% (cytomegalovirus in 39.7%); bacterial in 53.8% (mainly urinary tract infections). Non-infectious complications were: 1) cardiovascular risk factors:hypertension in 85.9%, hyperlipidemia in 16.7% and new onset diabetes post transplantation in 7.7%; 2) acute graft dysfunctionin 32.1%; graft chronic nephropathy 17.9%; 3) surgical complications 16.7%. In the first month after renal transplantation, surgical complications (11.5%) and bacterial infections were the most prevalent complications. Between the 1st and the 6th month there were more bacterial (34.6% patients) and viral (17.9% patients) infections. From 6th month on, cardiovascular risk factors (89.7% patients) became the more prevalent. There was one death.Conclusions: The most frequent infections were viral, mainly CMV. Acute graft dysfunction was frequent after the 6th month, probably associated with poor compliance. New morbidities, namely cardiovascular risk factors, are emerging with the evolution of new diagnostic, prophylactic and therapeutic strategies for renal transplantation.

[Complications of pediatric renal transplantation]

BACKGROUND

Renal transplantation is the treatment of choice for children with end stage renal disease with positive impact on survival and quality of life. However, some complications affect morbidity and mortality. This study examines the renal transplantation complications profile in pediatric patients (<18 y).

MATERIAL AND METHODS

Retrospective analysis of clinical files from renal transplantation patients followed in Pediatric Nephrology Unit from September 1995 to August 2010. Collection of data regarding: demography, end stage renal disease etiology, previous renal replacement therapy, graft loss and death, complications: surgical, infectious and non-infectious (acute and chronic rejection, primary disease recurrence, metabolic and cardiovascular risk factors). Descriptive statistical analysis was performed.

RESULTS

78 children (male: 48.7%), mean age at renal transplantation: 11.7 4.1 years. Previous peritoneal dialysis in 49 (62.6%). Five patients (6.4%) with preemptive renal transplantation. Median follow up: 37.5 months (1-169). Main end stage renal disease etiologies were urologic conditions in 41% and glomerular disease in 28.2%. Infectious complications occurred in 74%: viral: 56.4% (cytomegalovirus in 39.7%); bacterial in 53.8% (mainly urinary tract infections). Non-infectious complications were: 1) cardiovascular risk factors: hypertension in 85.9%, hyperlipidemia in 16.7% and new onset diabetes post transplantation in 7.7%; 2) acute graft dysfunction in 32.1%; graft chronic nephropathy 17.9%; 3) surgical complications 16.7%. In the first month after renal transplantation, surgical complications (11.5%) and bacterial infections were the most prevalent complications. Between the 1st and the 6th month there were more bacterial (34.6% patients) and viral (17.9% patients) infections. From 6th month on, cardiovascular risk factors (89.7% patients) became the more prevalent. There was one death.

CONCLUSIONS

The most frequent infections were viral, mainly CMV. Acute graft dysfunction was frequent after the 6th month, probably associated with poor compliance. New morbidities, namely cardiovascular risk factors, are emerging with the evolution of new diagnostic, prophylactic and therapeutic strategies for renal transplantation.

Hyperuricemia in adult renal allograft recipients: prevalence and predictors

BACKGROUND

Hyperuricemia is a common complication after kidney transplantation that may adversely affect graft survival.

OBJECTIVE

Our aim was to determine the prevalence of hyperuricemia in a sample of adult kidney graft recipients and to investigate its predictors.

METHODS

A total of 302 patients were included in the study. We used univariate analyses to compare clinical characteristics between the hyper-and normouricemic groups. We used multivariate adjusted logistic regression to detect independent predictors of hyperuricemia. Hyperuricemia was defined as serum uric acid ≥6.5 mg/dL in women and ≥7.0 mg/dL in men or allopurinol use.

RESULTS

The patients had a mean age of 49.6 ± 13.4 years, a median posttransplantation time of 7.6 years, and a mean estimated glomerular filtration rate (eGFR) of 51.9 ± 18.46 mL/min. The prevalence of hyperuricemia was 42.1% (n = 127). Hyperuricemic patients were predominately male (P = .004), older (P = .038), and with lower eGFR (P < .001). They also had a higher prevalence of hypertension (P = .001), dyslipidemia (P = .004) and proteinuria (P = .001). Multivariate adjusted regression model showed as significant predictors of hyperuricemia: male gender (odds ratio [OR], 2.46; P = .002); impaired renal function (OR 1.33 for every 10 mL/min reduction in eGFR; P < .001), higher body weight (OR 1.09 for every 1 kg/m(2) increase of body mass index; P = .044), prednisolone use (OR 2.12; P = .035), and cyclosporine versus tacrolimus use (OR 2.44; P = .039).

CONCLUSIONS

The prevalence of posttransplant hyperuricemia was high, particularly in patients with classical cardiovascular risk factors and lower eGFR. However, our findings suggest that modifiable immunosuppression options could play a role in its management.

Electrical transport properties of CuS single crystals

Electrical resistivity, transverse magnetoresistance and thermoelectric power measurements were performed on CuS high quality single crystals in the range 1.2-300 K and under fields of up to 16 T. The zero field resistivity data are well described below 55 K by a quasi-2D model, consistent with a carrier confinement at lower temperatures, before the transition to the superconducting state. The transverse magnetoresistance develops mainly below 30 K and attains values as large as 470% for a 16 T field at 5 K, this behaviour being ascribed to a band effect mechanism, with a possible magnetic field induced DOS change at the Fermi level. The transverse magnetoresistance shows no signs of saturation, following a power law with field Δρ/ρ(0) ∝ H(1.4), suggesting the existence of open orbits for carriers at the Fermi surface. The thermoelectric power shows an unusual temperature dependence, probably as a result of the complex band structure of CuS.