Project description:KEAP1 overexpressed and NRF2 siRNA knockdown A549 NSCLC cells were used to identify downstream genes of NRF2 pathway separately and by combinatorial analysis. We used triplicate microarrays of transfected A549 cells with mKeap1-GFP for overexpression, siRNAs targeting NRF2 for knockdown and siGFP as control respectively. As a result, we identified several genes which are involved in cancer metabolic functions in these cells. We used microarrays to identify the gene downregulated in both KEAP1 overexpressed and NRF2 siRNA knockdown A549 NSCLC cells and found a subset of downregulated genes which are involved in metabolic functions.
Project description:Nrf2-Keap1 signaling pathway protects cells against photo-oxidative stress. Yet in recent works, its role in melanogenesis together with cell protection functions against oxidative stress has been gaining interest. However, its effect on melanogenesis still has contradictory results from different studies. The aims of our study were to investigate the effect of Keap1 silencing in melanocyte on melanogenesis and its associated mechanism. Primary human epidermal melanocytes and melan-a cell line were used for this experiment. RNA sequencing was done to identify genes involved in melanocyte biology using Keap1 knockdown through siRNA techniques. And melanogenesis and the expression of melanogenesis-associated molecules were evaluated in Keap1 silenced melanocyte to examine the effects of Keap1 on melanogenesis, melanocyte growth, and related pathways. RNA-sequencing data revealed that Keap1 knockdown in primary human epidermal melanocytes (PHEMs) induced cell survival-related gene expression. Additionally, siRNA-mediated inhibition of Keap1 led to upregulation of MITF and melanogenesis-associated molecules along with Nrf2 activation in PHEMs. HO-1, a major gene that is upregulated in RNA-sequencing using Keap1-silenced PHEMs, protected melanocytes against H2O2-induced cell death and upregulated MITF and β-catenin expression. Further, increased expression of melanogenesis-associated molecules after Keap1 silencing was validated to occur through HO-1-associated β-catenin activation in a Keap1 and HO-1 double knockdown experiment. This work suggests that Keap1 silencing in melanocytes induced melanogenesis and the expression of melanogenesis-associated molecules through HO-1-associated β-catenin activation. Keap1 downregulation in melanocytes is important for cell proliferation and survival.
Project description:To elucidate the mechanisms by which Nrf2 regulates cell growth, we performed global gene expression profiling of A549 lung cancer cells with knockdown of Nrf2. Gene networks associated with carbohydrate metabolism and drug metabolism were significantly downregulated in Nrf2-depleted A549 cells. Gene Set Enrichment Analysis revealed significant enrichment of genes associated with carbohydrate catabolic processes, positive regulation of metabolic processes, PPP, and arachidonic acid metabolism. In summary, this analysis revealed that Nrf2 positively regulates transcription of genes that play key roles in central carbon metabolism. A549 cells were transfected with non targeting NS siRNA or siRNA targeting Nrf2. Mock transfected A549 cells were treated with transfection reagent alone. We had 3 biological replicates for each of the 3 groups. Ninty six hours post transfection, cells were lysed and total RNA was isolated.
Project description:The transcription factor NF-E2-related factor 2 (Nrf2) induces cytoprotective genes, but has also been linked to the regulation of hepatic energy metabolism. In order to assess the pharmacological potential of hepatic Nrf2 activation in metabolic disease, Nrf2 was activated over 8 weeks in mice on Western diet using two different siRNAs against kelch-like ECH-associated protein 1 (Keap1), the inhibitory protein of Nrf2. Whole genome expression analysis followed by pathway analysis demonstrated that the suppression of Keap1 expression induced genes that are involved in anti-oxidative stress defense and biotransformation, pathways proving the activation of Nrf2 by the siRNAs against Keap1. The expression of neither fatty acid- nor carbohydrate-handling proteins was regulated by the suppression of Keap1. Metabolic profiling of the animals did also not show effects on plasma and hepatic lipids, energy expenditure or glucose tolerance by the activation of Nrf2. The data indicate that hepatic Nrf2 is not a major regulator of intermediary metabolism in mice. Gene expression profile of mouse liver samples from 8-week-old male C57BL6/J mice (N=24) treated with liver-selective Keap1-specific siRNA (group 1: siKeap1-1, N=8; group 2: siKeap1-2, N=8) or unspecific scrambled control siRNA (group 3: siControl, N=8)
Project description:To examine the role of NRF2 in accelerating cell proliferation and to identify the target genes responsible for this function, transcriptome analysis was performed using A549 cells, in which NRF2 is constitutively activated. NRF2 was knocked down by siRNA against NRF2, and the gene expression profile was compared with that of A549 cells treated with control siRNA. To exclude off-target effects, three different siRNAs against NRF2 was independently applied. NRF2 siRNA or control siRNA was transfected into A549 cells. Cells were harvested 24 hours after transfection, and total RNA was purified.
Project description:Background: Non-Small Cell Lung Cancer (NSCLC) presents as a highly metastatic disease with Kras and P53 as prevalent oncogenic driver mutations. Endocytosis, through its role in receptor recycling and enrichment, is important for cancer cell proliferation and metastasis. Huntingtin Interacting Protein 1 (HIP1) is a clathrin mediated endocytic adapter protein found overexpressed in different cancers. However, conflicting roles both as a tumour promoter and suppressor are reported. HIP1 expression is found repressed at advanced stages and some HIP1-ALK fusions are reported in NSCLC patients. However, the molecular mechanisms and implications of HIP1 depletion are not completely understood. Methods: HIP1 depletion was performed using siRNA transient transfection and validated using immunoblotting for each experiment. HIP1 depleted A549 cells were analysed for deregulated global proteome using label-free LC-MS. Gene expression dataset was analysed using TCGA, GTeX and GEO to explore HIP1 expression in Lung cancer patients. Kaplan–Meier Plotter database was used to analyse the survival correlation between HIP1 mRNA expression in lung cancer patients. Various functional assays such as matrigel based invasion, trans-well migration, soft agar colony, tube formation are performed after HIP1 depletion. NRF2 inhibitor was used after HIP1 knockdown to assess its effect on invasion and soft agar colony formation. Results: In silico analysis of HIP1 transcript expression reveals that it is reduced in high-grade and metastatic lung cancer patients correlating with poor survival. Global proteome profiling reveals that HIP1 depleted A549 cells are enriched in pathways associated with metabolism, proliferation and survival. Molecular and functional analysis indicate higher invasive ability of HIP1 depleted cells. The secretome from HIP1 depleted cells also increases the angiogenic potential of HUVEC cells. NRF2 inhibition in HIP1 depleted cells reduces invasion of NSCLC cells with different driver mutations. Conclusion: Our study shows that HIP1 depletion leads to activation of various molecular pathways responsible for cell proliferation and survival. Additionally, enhancement of invasion in HIP1 depleted subsets of NSCLC cells is via upregulation of NRF2 and can be reversed by its inhibitor.
Project description:Sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables, is a potent inhibitor of experimental mammary carcinogenesis and may be an effective, safe chemopreventive agent for use in humans. SFN acts in part on the Keap1/Nrf2 pathway to regulate a battery of cytoprotective genes. In this study transcriptomic and proteomic changes in the estrogen receptor negative, non tumorigenic human breast epithelial MCF10A cell line were analyzed following SFN treatment or KEAP1 knockdown with siRNA using microarray and stable isotopic labeling with amino acids in culture (SILAC), respectively. Changes in selected transcripts and proteins were confirmed by PCR and Western blot in MCF10A and MCF12A cells. There was strong correlation between the transcriptomic and proteomic responses in both the SFN treatment (R=0.679, P<0.05) and KEAP1 knockdown (R=0.853, P<0.05) experiments. Common pathways for SFN treatment and KEAP1 knockdown were xenobiotic metabolism and antioxidants, glutathione metabolism, carbohydrate metabolism and NADH/NADPH regeneration. Moreover, these pathways were most prominent in both the transcriptomic and proteomic analyses. The aldo-keto reductase family members, AKR1B10, AKR1C1, AKR1C2 and AKR1C3, as well as NQO1 and ALDH3A1, were highly upregulated at both the transcriptomic and proteomic level. Collectively, these studies served to identify potential biomarkers that can be used in clinical trials to investigate the initial pharmacodynamic action of SFN in the breast. MCF10A cells were treated with SFN or had KEAP1 knocked down by siRNA.
Project description:We identified RNA binding motif protein 47 (RBM47) as a target gene of transforming growth factor (TGF)-beta in mammary gland epithelial cells (NMuMG cells) that have undergone the epithelial-to-mesenchymal transition (EMT). TGF-beta repressed RBM47 expression in NMuMG cells and lung cancer cell lines. Expression of RBM47 correlated with good prognosis in patients with lung, breast, and gastric cancer. RBM47 suppressed the expression of cell metabolism-related genes, which were the direct targets of nuclear factor erythroid 2-related factor 2 (Nrf2; also known as NFE2L2). RBM47 bound to KEAP1 and Cullin3 mRNAs, and knockdown of RBM47 inhibited their protein expression, which led to enhanced binding of Nrf2 to target genomic regions. Knockdown of RBM47 also enhanced the expression of some Nrf2 activators, p21/CDKN1A and MafK induced by TGF-beta. Both mitochondrial respiration rates and the side population cells in lung cancer cells increased in the absence of RBM47. Our findings, together with the enhanced tumor formation and metastasis of xenografted mice by knockdown of the RBM47 expression, suggested tumor suppressive roles for RBM47 through the inhibition of Nrf2 activity. Effect of shRNA for RBM47 and TGF-beta on gene expression was evaluated by RNA-seq and RBM47-bound RNAs were identified by RIP-seq in A549 cells.
Project description:The nuclear factor erythroid 2-like 2 (NFE2L2; NRF2) signal pathway is frequently deregulated in human cancers. The critical functions of NRF2 other than transcriptional activation in cancers remain largely unknown. Here, we uncovered a previously unrecognized role of Nrf2 in RNA splicing via regulating survival of motor neuron protein (SMN). Here, we performed next-generation high throughput global RNA-sequencing of siNrf2-C27 and siGFP-C5, which are stable NRF2-knockdown and control cell lines derived from A549 NSCLC cells, respectively To investigate whether NRF2 plays any role in RNA splicing.