DACH1 Expresison in Osteosarcoma and Its Relationship with Proliferation and Angiogenesis

Dach1 deficiency drives alveolar epithelium apoptosis in pulmonary fibrosis via modulating C-Jun/Bim activity

Dysregulation of type II alveolar epithelial cells (AECII) plays a vital role in the initiation and development of pulmonary fibrosis (PF). Dachshund homolog 1 (Dach1), frequently expressed in epithelial cells with stem cell potential, controls cell proliferation, apoptosis, and cell cycle in tissue development and disease process. In this study, we demonstrated that the lungs collected from PF patients and mice of Bleomycin (BLM)-treated were characterized by low expression of Dachshund homolog 1 (Dach1), especially in AECII. Dach1 deficiency in the alveolar epithelium exacerbated PF in BLM-treated mice, as evidenced by reduced pulmonary function and increased expression of fibrosis markers. Rather, treatment with lung-specific overexpression of Dach1 alleviated histopathological damage, lung compliance, and fibrosis in BLM-treated mice. Moreover, overexpression of Dach1 could inhibit epithelial apoptosis in vitro. Conversely, primary AECII with Dach1 depletion were more susceptible to apoptosis in vivo. Mechanically, Dach1 combined with C-Jun protooncogene selectively bound to the promoter of B-cell lymphoma 2 interacting mediators of cell death (Bim), by which it repressed Bim expression and alleviated epithelial apoptosis. Taken together, our data support that Dach1 in AECII contributes to the progression of PF and may be a viable target for the prevention and treatment of PF.

The regulation of cytokine signaling by retinal determination gene network pathway in cancer

Tumor environment plays a pivotal role in determining cancer biology characteristics. Cytokine factors, as a critical component in tumor milieu, execute distinct functions in the process of tumorigenesis and progression via the autocrine or paracrine manner. The retinal determination gene network (RDGN), which mainly comprised DACH, SIX, and EYA family members, is required for the organ development in mammalian species. While the aberrant expression of RDGN is involved in the proliferation, apoptosis, angiogenesis, and metastasis of tumors via interacting with different cytokine-related signals, such as CXCL8, IL-6, TGF-β, FGF, and VEGF, in a cell- or tissue-dependent manner. Thus, joint detection of this pathway might be used as a potential biomarker for the stratification of target therapy and for the precision prediction of the prognosis of cancer patients.

Decreased DACH1 expression in glomerulopathy is associated with disease progression and severity

Cell fate determination factor dachshund1 (DACH1) is a chromosome-associated protein that regulates cellular differentiation throughout development. Recent genome-wide association studies have show that missense mutation in DACH1 leads to hereditary renal hypodysplasia. Renal DACH1 expression can be used to estimate glomerular filtration rate (eGFR). We firstly characterized the function of DACH1 in normal and diseased renal tissue using immunohistochemistry to assess DACH1 in human renal biopsy specimens from 40 immunoglobulin A nephropathy (IgAN) patients, 20 idiopathic membranous nephropathy (IMN) patients, and 15 minimal change disease (MCD) patients. We found that DACH1 expression was decreased in the nephropathy group relative to healthy controls. DACH1 staining in the glomerulus correlated positively with eGFR (r = 0.41, p < 0.001) but negatively with serum creatinine (r = −0.37, p < 0.01). In vitro, DACH1 overexpression in human podocytes or HK2 cells decreased expression of cyclin D1, but increased expression of p21 and p53, which suggested that DACH1 overexpression in human podocytes or HK2 cells increased the G1/S phase or G2/M cell arrest. Together, These findings indicate that DACH1 expression is decreased in glomerulopathy imply a potential role for DACH1 in the this development of human chornic glomerulopathy. These data suggest that DACH1 is a potential a marker of disease progression and severity for glomerular diseases.

Establishment and genomic characterization of the new chordoma cell line Chor-IN-1

Chordomas are rare, slowly growing tumors with high medical need, arising in the axial skeleton from notochord remnants. The transcription factor "brachyury" represents a distinctive molecular marker and a key oncogenic driver of chordomas. Tyrosine kinase receptors are also expressed, but so far kinase inhibitors have not shown clear clinical efficacy in chordoma patients. The need for effective therapies is extremely high, but the paucity of established chordoma cell lines has limited preclinical research. Here we describe the isolation of the new Chor-IN-1 cell line from a recurrent sacral chordoma and its characterization as compared to other chordoma cell lines. Chor-IN-1 displays genomic identity to the tumor of origin and has morphological features, growth characteristics and chromosomal abnormalities typical of chordoma, with expression of brachyury and other relevant biomarkers. Chor-IN-1 gene variants, copy number alterations and kinome gene expression were analyzed in comparison to other four chordoma cell lines, generating large scale DNA and mRNA genomic data that can be exploited for the identification of novel pharmacological targets and candidate predictive biomarkers of drug sensitivity in chordoma. The establishment of this new, well characterized chordoma cell line provides a useful tool for the identification of drugs active in chordoma.