Mutations of PTCH1 gene in two pedigrees with bifid rib-basal cell nevus-jaw cyst syndrome / 浙江大学学报·医学版

Two male patients with bifid rib-basal cell nevus-jaw cyst syndrome (BCNS) were admitted to Department of Stomatology, the First Affiliated Hospital of Bengbu Medical College due to radiological findings of multiple low density shadows in the jaw. Clinical and imaging findings showed thoracic malformation, calcification of the tentorium cerebellum and falx cerebrum as well as widening of the orbital distance. Whole exon high-throughput sequencing was performed in two patients and their family members. The heterozygous mutations of c.C2541C>A(p.Y847X) and c.C1501C>T(p.Q501X) in PTCH1 gene were detected in both patients. Diagnosis of BCNS was confirmed. The heterozygous mutations of PTCH1 gene locus were also found in the mothers of the two probands. Proband 1 showed clinical manifestations of low intelligence, and heterozygous mutations of c.C2141T(p.P714L) and c.G3343A(p.V1115I) were detected in FANCD2 gene. Proband 2 had normal intelligence and no FANCD2 mutation. The fenestration decompression and curettage of jaw cyst were performed in both patients. Regular follow-up showed good bone growth at the original lesion, and no recurrence has been observed so far.

Expression of FANCD2 in Sporadic Breast Cancer and Clinicopathological Analysis / 华中科技大学学报（医学）（英德文版）

FANCD2 is involved in DNA damage repair and maintenance of chromosome stability.The purpose of this study was to investigate the expression of FANCD2 in sporadic breast cancer tissues and its association with clinicopathological features.A total of 162 Chinese women with invasive breast carcinoma who had no family history in first-degree relatives and 12 normal breast tissues were examined.The expression of FANCD2 was detected by immunohistochemical staining based on a tissue microarray technique.SAS system was used to analyze the data.Twenty-one out of the 162 invasive breast cancers(13%)were negative for FANCD2.The mean percentage of FANCD2 positive cells was significantly lower in breast cancers than in controls(P＜0.05).FANCD2 expression was significantly inversely associated with histological grade and TNM stage(P＜0.05),but not with axillary lymph node status or other conventional prognostic markers such as ER,PR,Her-2 and PCNA(P＞0.05).It was suggested that FANCD2 may play a critical role in breast carcinogenesis.It may become a valuable and independent marker for identifying women with sporadic breast cancer and evaluating the prognosis.

FANCD2 Western blot as a diagnostic tool for Brazilian patients with Fanconi anemia

Fanconi anemia is a rare hereditary disease showing genetic heterogeneity due to a variety of mutations in genes involved in DNA repair pathways, which may lead to different clinical manifestations. Phenotypic variability makes diagnosis difficult based only on clinical manifestations, therefore laboratory tests are necessary. New advances in molecular pathogenesis of this disease led researchers to develop a diagnostic test based on Western blot for FANCD2. The objective of the present study was to determine the efficacy of this method for the diagnosis of 84 Brazilian patients with Fanconi anemia, all of whom tested positive for the diepoxybutane test, and 98 healthy controls. The FANCD2 monoubiquitinated isoform (FANCDS+/FANCD2L-) was not detected in 77 patients (91.7 percent). In 2 patients (2.4 percent), there was an absence of both the monoubiquitinated and the non-ubiquitinated proteins (FANCD2S-/FANCD2L-) and 5 patients (5.9 percent) had both isoforms (FANCD2S+/FANCD2L+). This last phenotype suggests downstream subtypes or mosaicism. All controls were diepoxybutane negative and were also negative on the FANCD2 Western blot. The Western blot for FANCD2 presented a sensitivity of 94 percent (79/84) and specificity of 100 percent (98/98). This method was confirmed as an efficient approach to screen Brazilian patients with deleterious mutations on FANCD2 (FANCD2S-/FANCD2L-) or other upstream genes of the FA/BRCA pathway (FANCDS+/FANCD2L-), to confirm the chromosome breakage test and to classify patients according to the level of FA/BRCA pathway defects. However, patients showing both FANCD2 isoforms (FANCD2S+/FANCD2L+) require additional studies to confirm mutations on downstream Fanconi anemia genes or the presence of mosaicism.