RESUMEN
To better define the place of multiplex ligation-dependent probe amplification (MLPA) in routine cytogenetic diagnosis in chronic lymphocytic leukemia (CLL), we compared MLPA and fluorescence in situ hybridization (iFISH) data obtained in 77 CLL patients. Although MLPA detected most recurrent copy number genomic aberrations (90.9%), false-negative results were found in cases with small-size abnormal clones and false-positive MLPA findings resulting from point mutations (TP53) or an apparent lack of probe specificity (chromosome 19) were observed. Thus, MLPA may be a useful complementary but not alternative approach for iFISH testing of genomic aberration in CLL.
Asunto(s)
Aberraciones Cromosómicas , Pruebas Diagnósticas de Rutina/métodos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/genética , Reacción en Cadena de la Polimerasa Multiplex , Adulto , Anciano , Anciano de 80 o más Años , Aberraciones Cromosómicas/estadística & datos numéricos , Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 12/genética , Cromosomas Humanos Par 13/genética , Cromosomas Humanos Par 17/genética , Femenino , Frecuencia de los Genes , Humanos , Hibridación Fluorescente in Situ , Leucemia Linfocítica Crónica de Células B/epidemiología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa Multiplex/métodos , PronósticoRESUMEN
PURPOSE: Genetic instability plays an important role in ovarian carcinogenesis. We investigated the level of telomere shortening and genomic instability in early and preinvasive stages of ovarian cancer, serous tubal intraepithelial carcinoma (STIC), and tubo-ovarian dysplasia (TOD). EXPERIMENTAL DESIGN: Fifty-one TOD from prophylactic salpingo-oophorectomies with BRCA1 or 2 mutation, 12 STICs, 53 tubo-ovarian high-grade serous carcinoma, and 36 noncancerous controls were laser capture microdissected from formalin-fixed, paraffin-embedded sections, analyzed by comparative genomic hybridization (array CGH) and for telomere length (using quantitative real-time PCR based on the Cawthon's method). TOD and STICs were defined by morphologic scores and immunohistochemical expressions of p53, Ki67, and γH2AX. RESULTS: TOD showed marked telomere shortening compared with noncancerous controls (P < 10(-7)). STICs had even shorter telomeres than TOD (P = 0.0008). Ovarian carcinoma had shorter telomeres than controls but longer than STICs and dysplasia. In TOD, telomeres were significantly shorter in those with BRCA1 mutation than in those with BRCA2 mutation (P = 0.005). In addition, γH2AX expression in TOD and STIC groups with short telomeres was significantly increased (P < 10(-7)). In dysplastic epithelium, we found subtle genomic alterations, in contrast to more important genomic imbalances in STICs. The total number of genetic alterations was the highest in ovarian cancers. CONCLUSIONS: These findings suggest that genetic instability occurs in early stages of ovarian tumorigenesis. STICs and noninvasive dysplasia are likely an important step in early serous ovarian neoplasia.