RESUMEN
Our group and others had previously developed a high throughput procedure to map translocation breakpoints using chromosome flow sorting in conjunction with microarray-based comparative genomic hybridization (arrayCGH). Here we applied both conventional positional cloning and integrated arrayCGH procedures to the mapping of constitutional chromosome anomalies in four patients with renal cell cancer (RCC), three with a chromosome 3 translocation, and one with an insertion involving chromosome 3. In one of these patients, who was carrying a t(3;4)(p13;p15), the KCNIP4 gene was found to be disrupted. KCNIP4 belongs to a family of potassium channel-interacting proteins and is highly expressed in normal kidney cells. In addition, KCNIP4 splice variants have specifically been encountered in RCC.
Asunto(s)
Carcinoma de Células Renales/genética , Neoplasias Renales/genética , Proteínas de Interacción con los Canales Kv/genética , Translocación Genética , Línea Celular Tumoral , Rotura Cromosómica , Mapeo Cromosómico , Cromosomas Humanos Par 3 , Cromosomas Humanos Par 4 , Clonación Molecular , Humanos , Hibridación Fluorescente in Situ , Pérdida de Heterocigocidad , Mutagénesis InsercionalRESUMEN
OBJECTIVE: To determine the diagnostic accuracy of noninvasive fetal sex determination in maternal plasma. METHODS: All consecutive patients for whom fetal sex determination in maternal plasma was performed in our laboratory from 2003 up to 2009 were included in the study. Real-time polymerase chain reaction was performed for the SRY gene and multicopy DYS14 marker sequence. A stringent diagnostic algorithm was applied. In the case of a positive result for both Y chromosome-specific assays, a male-bearing pregnancy was reported. In the case of a negative result, the presence of fetal DNA was ascertained through the use of 24 biallelic insertion/deletion polymorphisms or paternally inherited blood group antigens. Only if the presence of fetal DNA was confirmed was a female-bearing pregnancy reported. Results were compared with the pregnancy outcomes. RESULTS: A total of 201 women were tested. The median gestational age was 9 0/7 weeks (interquartile range 8 0/7 to 10 0/7 weeks). In 189 of 201 cases (94%), a test result was issued; in 10 cases, the presence of fetal DNA could not be confirmed; in two cases, an early miscarriage was observed. Pregnancy outcome was obtained in 197 cases, including 105 male-bearing and 81 female-bearing pregnancies and 11 miscarriages. Sensitivity and specificity of the test were 100% (95% confidence intervals 96.6-100% and 95.6-100%, respectively). In all 10 cases in which the presence of fetal DNA could not be confirmed, a female was born. CONCLUSION: Noninvasive fetal sex determination in maternal plasma is highly reliable and clinically applicable. LEVEL OF EVIDENCE: III.
Asunto(s)
Análisis para Determinación del Sexo/métodos , Sistema Libre de Células , Análisis Citogenético , ADN/análisis , Femenino , Humanos , Reacción en Cadena de la Polimerasa , Embarazo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Proteína de la Región Y Determinante del Sexo/sangreRESUMEN
FBXW7 (alias CDC4) is a p53-dependent tumor suppressor gene that exhibits mutations or deletions in a variety of human tumors. Mutation or deletion of the FBXW7 gene has been associated with an increase in chromosomal instability and cell cycle progression. In addition, the FBXW7 protein has been found to act as a component of the ubiquitin proteasome system and to degrade several oncogenic proteins that function in cellular growth regulatory pathways. By using a rapid breakpoint cloning procedure in a case of renal cell cancer (RCC), we found that the FBXW7 gene was disrupted by a constitutional t(3;4)(q21;q31). Subsequent analysis of the tumor tissue revealed the presence of several anomalies, including loss of the derivative chromosome 3. Upon screening of a cohort of 29 independent primary RCCs, we identified one novel pathogenic mutation, suggesting that the FBXW7 gene may also play a role in the development of sporadic RCCs. In addition, we screened a cohort of 48 unrelated familial RCC cases with unknown etiology. Except for several known or benign sequence variants such as single nucleotide polymorphisms (SNPs), no additional pathogenic variants were found. Previous mouse models have suggested that the FBXW7 gene may play a role in the predisposition to tumor development. Here we report that disruption of this gene may predispose to the development of human RCC.