Identification of de novo mutations and rare variants in hypoplastic left heart syndrome
CLINICAL GENETICS
Authors: Iascone, M.; Ciccone, R.; Galletti, L.; Marchetti, D.; Seddio, F.; Lincesso, A. R.; Pezzoli, L.; Vetro, A.; Barachetti, D.; Boni, L.; Federici, D.; Soto, A. M.; Comas, J. V.; Ferrazzi, P.; Zuffardi, O.
Abstract
Iascone M, Ciccone R, Galletti L, Marchetti D, Seddio F, Lincesso AR, Pezzoli L, Vetro A, Barachetti D, Boni L, Federici D, Soto AM, Comas JV, Ferrazzi P, Zuffardi O. Identification of de novo mutations and rare variants in hypoplastic left heart syndrome. Hypoplastic left heart syndrome (HLHS) is one of the most severe congenital heart malformations, characterized by underdevelopment of the structures in the left heartaorta complex. The majority of cases are sporadic. Although multiple genetic loci have been tentatively implicated in HLHS, no gene or pathway seems to be specifically associated with the disease. To elucidate the genetic basis of HLHS, we analyzed 53 well-characterized patients with isolated HLHS using an integrated genomic approach that combined DNA sequencing of five candidate genes (NKX2-5, NOTCH1, HAND1, FOXC2 and FOXL1) and genome-wide screening by high-resolution array comparative genomic hybridization. In 30 patients, we identified two novel de novo mutations in NOTCH1, 23 rare patients inherited gene variants in NOTCH1, FOXC2 and FOXL1, and 33 rare patients mostly inherited copy-number variants. Some of the identified variations coexisted in the same patient. The biological significance of such rare variations is unknown, but our findings strengthen the role of NOTCH pathway in cardiac valve development, indicating that HLHS is, at least in part, a valve disease. This is the first report of de novo mutations associated with isolated HLHS. Moreover, the coexistence of multiple rare variants suggests in some cases a cumulative effect, as shown for other complex disease.
Foxl1 inhibits tumor invasion and predicts outcome in human renal cancer
INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY
Authors: Yang, Feng-Qiang; Yang, Feng-Ping; Li, Wei; Liu, Min; Wang, Guang-Chun; Che, Jian-Ping; Huang, Jian-Hua; Zheng, Jun-Hua
Abstract
The Forkhead Box L1 (Foxl1) transcription factor regulates epithelial proliferation and development of gastrointestinal tract, and has been implicated in gastrointestinal and pancreatic tumorigenesis. However, the role of Foxl1 in renal cancer development and progression remains to be elucidated. The study was conducted to investigate the expression of Foxl1 and its prognostic significance in clear cell renal cell carcinoma (ccRCC). Meanwhile, the function of Foxl1 in human ccRCC was further investigated in cell culture models. Methods: Real-time quantitative PCR, western-blot, immunohistochemistry were used to explore Foxl1 expression in primary ccRCC clinical specimens and ccRCC cell lines. Foxl1 expression was up-regulated by over-expression vector in 786-O and ACHN cells, proliferation, cell cycle, migration and invasion were assayed. Results: Foxl1 expression was down-regulated in the majority of the ccRCC clinical tissue specimens at both mRNA and protein levels. Clinic pathological analysis showed that Foxl1 expression was significantly correlated with tumor stage, lymph node metastasis, distant metastasis, clinical TNM stage (cTNM) and histological grade of renal cancer. The Kaplan-Meier survival curves revealed that low Foxl1 expression was associated with poor prognosis in ccRCC patients. Foxl1 expression was an independent prognostic marker of overall ccRCC patient survival in a multivariate analysis. Mechanistic analyses demonstrated that over-expression of Foxl1 inhibits tumor cell growth, migration and invasion in renal cancer cells. Conclusions: These results suggest that Foxl1 expression is a candidate predictor of clinical outcome in patients with resected ccRCC and it plays an inhibitory role in renal tumor progression.