Project description:<p>BRCA1 mutations are a hallmark of hereditary ovarian cancer, strongly linked to deficiencies in homologous recombination (HR) DNA repair and impaired DNA replication fork protection. However, its roles in cancer progression beyond maintaining genomic integrity remain poorly understood. Through metabolomics approaches, we found BRCA1-deficiency strikingly increased choline metabolism. Loss of BRCA1 promotes choline uptake through upregulating choline transporter-like protein 4 (CTL4). BRCA1 directly binds and recruits EZH2-mediated H3K27Me3 deposition to CTL4 promoter. CTL4 was therefore overexpressed in ovarian cancer tissues with BRCA1 mutations. Furthermore, BRCA1-deficiency significantly promotes ovarian cancer invasion, while inhibition of CTL4 reverses the high metastatic potential of BRCA1-deficient ovarian cancer cells, suggesting the functionality and specificity of CTL4 as a therapeutic target. Additionally, we discovered that phosphocholine, the choline metabolite increased by CTL4 overexpression, interacted with and stabilized the epithelial-to-mesenchymal transition inducer FAM3C in BRCA1-deficient ovarian cancer cells. Importantly, we identified a potent CTL4 inhibitor, DT-13, which significantly reduces choline metabolism and effectively suppresses metastasis in BRCA1-deficient ovarian cancers. Therefore, our study uncovers a mechanism underlying metastasis in BRCA1-deficient cancers and identifies CTL4 as a therapeutic target for metastatic ovarian cancer patients with BRCA1 mutations.</p>
Project description:Transcriptional profiling of Homo sapiens inflammatory skin diseases (whole skin biospies): Psoriasis (Pso), vs Atopic Dermatitis (AD) vs Lichen planus (Li), vs Contact Eczema (KE), vs Healthy control (KO) In recent years, different genes and proteins have been highlighted as potential biomarkers for psoriasis, one of the most common inflammatory skin diseases worldwide. However, most of these markers are not psoriasis-specific but also found in other inflammatory disorders. We performed an unsupervised cluster analysis of gene expression profiles in 150 psoriasis patients and other inflammatory skin diseases (atopic dermatitis, lichen planus, contact eczema, and healthy controls). We identified a cluster of IL-17/TNFα-associated genes specifically expressed in psoriasis, among which IL-36γ was the most outstanding marker. In subsequent immunohistological analyses IL-36γ was confirmed to be expressed in psoriasis lesions only. IL-36γ peripheral blood serum levels were found to be closely associated with disease activity, and they decreased after anti-TNFα-treatment. Furthermore, IL-36γ immunohistochemistry was found to be a helpful marker in the histological differential diagnosis between psoriasis and eczema in diagnostically challenging cases. These features highlight IL-36γ as a valuable biomarker in psoriasis patients, both for diagnostic purposes and measurement of disease activity during the clinical course. Furthermore, IL-36γ might also provide a future drug target, due to its potential amplifier role in TNFα- and IL-17 pathways in psoriatic skin inflammation. In recent years, different genes and proteins have been highlighted as potential biomarkers for psoriasis, one of the most common inflammatory skin diseases worldwide. However, most of these markers are not psoriasis-specific but also found in other inflammatory disorders. We performed an unsupervised cluster analysis of gene expression profiles in 150 psoriasis patients and other inflammatory skin diseases (atopic dermatitis, lichen planus, contact eczema, and healthy controls). We identified a cluster of IL-17/TNFα-associated genes specifically expressed in psoriasis, among which IL-36γ was the most outstanding marker. In subsequent immunohistological analyses IL-36γ was confirmed to be expressed in psoriasis lesions only. IL-36γ peripheral blood serum levels were found to be closely associated with disease activity, and they decreased after anti-TNFα-treatment. Furthermore, IL-36γ immunohistochemistry was found to be a helpful marker in the histological differential diagnosis between psoriasis and eczema in diagnostically challenging cases. These features highlight IL-36γ as a valuable biomarker in psoriasis patients, both for diagnostic purposes and measurement of disease activity during the clinical course. Furthermore, IL-36γ might also provide a future drug target, due to its potential amplifier role in TNFα- and IL-17 pathways in psoriatic skin inflammation.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Colorectal carcinoma is the third leading cause of cancer-related death in the United States. In order to understand the mechanism/signaling pathways responsible for invasion, migration and metastasis in colorectal cancer, we developed an integrative and comparative genetic approach to infer transcriptional regulatory mechanisms underlying colon cancer progression. Accordingly, we filtered fourteen human colorectal cancer (CRC) microarray data sets, from an immune competent mouse model of metastasis to identify known and novel transcriptional regulators in CRC. Using this approach, Nuclear Factor of Activated T cells (NFAT) family of transcription factors were identified as metastasis driver of colon cancer. NFAT family of transcription factors is known to induce gene transcription in various disease processes, including carcinogenesis. We used parental and metastatic derivatives of MC38 mouse colon cancer cells (MC38Par and MC38Met, respectively) to evaluate the role of NFATc1 in cancer cell invasiveness. We found that high NFATc1 expression correlates with significantly increased (p<0.0001) Trans-Endothelial Invasion (TEI) in MC38Met cells. Conversely, RNAi-based inhibition of NFATc1 expression and functional inhibition with calcineurin inhibitor FK506 in MC38Met cells, both resulted in significant decreased TEI (p=0.0193 & p=0.0003). Furthermore, a set of predicted NFATc1 target mRNAs identified in our original analysis were downregulated by knock-down of NFATc1 or functional inhibition with FK506 in MC38Met cells. The expression level (mRNA) of predicted gene targets were high in human CRC specimens which had higher than median NFATc1 mRNA expression (n=11 out of total 22). The tumor-associated NFATc1 co-regulated gene signature is significantly correlated with both disease-specific and disease-free survival in Stage II and III CRC patients. We have successfully demonstrated a bioinformatics approach to identify a tumor promoter driver gene NFATc1. Our studies suggest a role of NFATc1 towards invasion and its co-regulated gene signature for poor outcomes in colorectal cancer. We developed an integrative and comparative genetic approach to infer transcriptional regulatory mechanisms underlying colon cancer progression. Using this approach, the Nuclear Factor of Activated T cells (NFAT) family of transcription factors were identified as metastasis driver of colon cancer. We used parental and metastatic derivatives of MC38 mouse colon cancer cells (MC38Par and MC38Met, respectively) to evaluate the role of NFATc1 in cancer cell invasiveness [GSE19073]. We found that high NFATc1 expression correlates with significantly increased (p<0.0001) Trans-Endothelial Invasion (TEI) in MC38Met cells. Conversely, RNAi-based inhibition of NFATc1 expression and functional inhibition with calcineurin inhibitor FK506 in MC38Met cells, both resulted in significant decreased TEI (p=0.0193 & p=0.0003). Furthermore, a set of predicted NFATc1 target mRNAs identified in our original analysis were downregulated by knock-down of NFATc1 or functional inhibition with FK506 in MC38Met cells. Finally, we generated a microarray gene expression dataset based on tumor samples collected from 122 CRC patients and tested whether the tumor-associated NFATc1co-regulated gene signature is correlated with patient survival. The following clinical information can be found in the characteristics fields of each sample; AJCC_STAGE: stage of cancer classified by AJCC (American Joint Committee on Cancer) staging system DFS_EVENT: disease free survival; cancer recurrence=1, no recurrence=0 DFS_TIME: disease free survival time (months) DSS_EVENT: disease specific survival; death from cancer=1,no death=0 DSS_TIME: disease specific survival time (months)