Non-collagen genes role in digenic Alport syndrome
BMC NEPHROLOGY
Authors: Daga, S.; Fallerini, C.; Furini, S.; Pecoraro, C.; Scolari, F.; Ariani, F.; Bruttini, M.; Mencarelli, M. A.; Mari, F.; Renieri, A.; Pinto, A. M.
Abstract
BackgroundAlport syndrome is a clinically heterogeneous nephropathy characterized by severe symptomatology at kidney level due to ultrastructural lesions of the glomerular basement membrane (GBM) as consequence of mutations in COL4 genes. The disease has been linked to COL4A3/COL4A4/COL4A5 mutations, which impair GBM functionality and can be inherited in a dominant, recessive or X-linked transmission. Although a targeted Next Generation Sequencing approach has allowed identifying families with pathogenic mutations in more than one COL4 3-4-5 heterotrimer encoding genes, leading to conclude for a digenic pattern of inheritance, the role of non-collagen genes in digenic Alport syndrome has not yet been established.MethodsWe employed a whole-exome sequencing approach on three families in whom a digenic pattern of transmission could be suspected because of a likely biparental contribution or an unexplained phenotype in the proband.ResultsWe identified in the three probands hypomorphic LAMA5 mutations co-inherited with pathogenic COL4 4-5 chains mutations. Segregation analysis revealed that the combination of LAMA5/COL4 variants co-segregate with a fully penetrant phenotype in line with a digenic inheritance.In one of the three probands an hypomorphic variant in NPHS2 was also found, suggesting that role of other kidney disease related-genes as modifiers.ConclusionThese findings validate the impact of LAMA5 mutations in digenic ATS and highlight the role of extracellular matrix's genes, basement membrane, slit diaphragm and podocyte cytoskeleton in ATS. This underline the need for a more extensive panel approach in the presence of a digenic ATS, in order to better define clinical severity and recurrence risk for family members.
In vivo Survivors of Transformed Mouse Ovarian Surface Epithelial Cells Display Diverse Phenotypes for Gene Expression and Tumorigenicity
TUMOR BIOLOGY
Authors: Li, Xiao-Lin; Zhang, Dong-Qing; Wang, David; Knight, David S.; Yin, Lija; Bao, Jianxiong; Liu, Yong-Yu; Glass, Jonathan; Mathis, J. Michael; Zhang, Qian-Jin
Abstract
Ovarian cancer is the fifth most common cause of cancer death in women. Due to a lack of appropriate animal models, studies involving tumorigenicity, tumor progression and immune response at the molecular level are limited. We isolated many clones derived from the survivors of a transformed mouse ovarian epithelial cell line IG-10 in immune-competent mice and found that the clones displayed diverse phenotypes. Most clones were deficient in components of the MHC-I antigen presentation pathway. Soft-agarose colony assays showed different growth rates among clones. However, this did not completely correlate with each clone's in vivo tumorigenicity regarding growth, tumor mass and ascites formation, suggesting the possibility that the clones may display contrasting intrinsic gene expression. We therefore performed two types of arrays to evaluate gene expression at transcriptional and translational levels. The results showed differences in expression of COL4 alpha 5, NOS-2, and SOCS-1 genes at the transcriptional level, MIP-2 gene at the protein level and CCL5, CXCL-10, IL-1 alpha genes at both transcriptional and protein levels between low and high tumorigenic clones. Thus, our animal cell model together with the identified genes may provide a useful tool to study ovarian cancer immune response, tumorigenicity and tumor-host cell interactions in the tumor microenvironment. Copyright (C) 2008 S. Karger AG, Basel