The Adrenomedullin Gene Is a Target for Negative Regulation by the Myc Transcription Complex

Abstract The Myc family of transcription factors plays a central role in vertebrate growth and development although relatively few genetic targets of the Myc transcription complex have been identified. In this study, we used mRNA differential display to investigate gene expression changes induced by the overexpression of the MC29 v-Myc oncoprotein in C3H10T1/2 mouse fibroblasts. We identified the transcript of the adrenomedullin gene (AM) as an mRNA that is specifically down-regulated in v-Myc overexpressing C3H10T1/2 cell lines as well as in a Rat 1a cell line inducible for c-Myc. Nucleotide sequence analysis of the mouse AM promoter reveals the presence of consensus CAAT and TATA boxes as well as an initiator element (INR) with significant sequence similarity to the INR responsible for Myc-mediated repression of the adenovirus major late promoter (AdMLP). Reporter gene assays confirm that the region of the AM promoter containing the INR is the target of Myc-mediated repression. Exogenous application of AM peptide to quiescent C3H10T1/2 cultures does not stimulate growth, and constitutive expression of AM mRNA in C3H10T1/2 cells correlates with a reduced potential of the cells to be cotransformed by v-Myc and oncogenic Ras p21. Additional studies showing that AM mRNA is underrepresented in C3H10T1/2 cell lines stably transformed by Ras p21 or adenovirus E1A suggest that AM gene expression is incompatible with deregulated growth in this cell line. We propose a model in which the repression of AM gene expression by Myc is important to the role of this oncoprotein as a potentiator of cellular transformation in C3H10T1/2 and perhaps other cell lines.

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Histone Deacetylase Inhibitors and Microtubule Inhibitors Induce Apoptosis in Feline Luminal Mammary Carcinoma Cells

Animals ◽

10.3390/ani11020502 ◽

2021 ◽

Vol 11 (2) ◽

pp. 502

Author(s):

Filipe Almeida ◽

Andreia Gameiro ◽

Jorge Correia ◽

Fernando Ferreira

Keyword(s):

Breast Cancer ◽

Gene Expression ◽

Cell Line ◽

Cell Lines ◽

Mammary Carcinoma ◽

Human Breast Cancer ◽

Histone Deacetylase Inhibitors ◽

Trichostatin A ◽

Human Breast ◽

Antitumor Effects

Feline mammary carcinoma (FMC) is the third most common type of neoplasia in cats, sharing similar epidemiological features with human breast cancer. In humans, histone deacetylases (HDACs) play an important role in the regulation of gene expression, with HDAC inhibitors (HDACis) disrupting gene expression and leading to cell death. In parallel, microtubules inhibitors (MTIs) interfere with the polymerization of microtubules, leading to cell cycle arrest and apoptosis. Although HDACis and MTIs are used in human cancer patients, in cats, data is scarce. In this study, we evaluated the antitumor properties of six HDACis (CI-994, panobinostat, SAHA, SBHA, scriptaid, and trichostatin A) and four MTIs (colchicine, nocodazole, paclitaxel, and vinblastine) using three FMC cell lines (CAT-MT, FMCp, and FMCm), and compared with the human breast cancer cell line (SK-BR-3). HDACis and MTIs exhibited dose-dependent antitumor effects in FMC cell lines, and for all inhibitors, the IC50 values were determined, with one feline cell line showing reduced susceptibility (FMCm). Immunoblot analysis confirmed an increase in the acetylation status of core histone protein HDAC3 and flow cytometry showed that HDACis and MTIs lead to cellular apoptosis. Overall, our study uncovers HDACis and MTIs as promising anti-cancer agents to treat FMCs.

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Characterization of the BCR promoter in Philadelphia chromosome-positive and -negative cell lines.

Molecular and Cellular Biology ◽

10.1128/mcb.11.4.1854 ◽

1991 ◽

Vol 11 (4) ◽

pp. 1854-1860 ◽

Cited By ~ 18

Author(s):

N P Shah ◽

O N Witte ◽

C T Denny

Keyword(s):

Transcription Factor ◽

Cell Lines ◽

Transcription Initiation ◽

Transcriptional Control ◽

Philadelphia Chromosome ◽

Gc Content ◽

Cellular Transformation ◽

Nucleotide Sequence Analysis ◽

Coding Sequences ◽

Gene Assay

The t(9;22) Philadelphia chromosome translocation fuses 5' regulatory and coding sequences of the BCR gene to the c-ABL proto-oncogene. This results in the formation of hybrid BCR-ABL mRNAs and proteins. The shift in ABL transcriptional control to the BCR promoter may play a role in cellular transformation mediated by this rearrangement. We have functionally localized the BCR promoter to a region 1 kb 5' of BCR exon 1 coding sequences by using a chloramphenicol acetyltransferase reporter gene assay. Nucleotide sequence analysis of this region revealed many consensus binding sequences for transcription factor SP1 as well as two potential CCAAT box binding factor sites and one putative helix-loop-helix transcription factor binding site. No TATA-like or "initiator" element sequences were found. Because of low steady-state levels of BCR mRNA and the high GC content (78%) of the promoter region, definitive mapping of transcription start sites required artificial amplification of BCR promoter-directed transcripts. Overexpression from the BCR promoter in a COS cell system was effective in demonstrating multiple transcription initiation sites. In order to assess the effects of chromosomal translocation on the transcriptional control of the BCR gene, we determined S1 nuclease protection patterns of poly(A)+ RNA from tumor cell lines. No differences were observed in the locations and levels of BCR transcription initiation sites between those lines that harbored the t(9;22) translocation and those that did not. This demonstrates that BCR promoter function remains intact in spite of genomic rearrangement. The BCR promoter is structurally similar to the ABL promoters. Together, this suggests that the structural fusion of BCR-ABL and not its transcriptional deregulation is primarily responsible for the transforming effect of the t(9;22) translocation.

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A CRISPR/Cas9 genome editing pipeline in the EndoC-βH1 cell line to study genes implicated in beta cell function

Wellcome Open Research ◽

10.12688/wellcomeopenres.15447.1 ◽

2019 ◽

Vol 4 ◽

pp. 150 ◽

Cited By ~ 3

Author(s):

Antje K. Grotz ◽

Fernando Abaitua ◽

Elena Navarro-Guerrero ◽

Benoit Hastoy ◽

Daniel Ebner ◽

...

Keyword(s):

Gene Expression ◽

Beta Cell ◽

Er Stress ◽

Cell Line ◽

Cell Lines ◽

Target Genes ◽

Gene Knockout ◽

Mrna Levels ◽

Beta Cell Line ◽

Human Beta Cell

Type 2 diabetes (T2D) is a global pandemic with a strong genetic component, but most causal genes influencing the disease risk remain unknown. It is clear, however, that the pancreatic beta cell is central to T2D pathogenesis. In vitro gene-knockout (KO) models to study T2D risk genes have so far focused on rodent beta cells. However, there are important structural and functional differences between rodent and human beta cell lines. With that in mind, we have developed a robust pipeline to create a stable CRISPR/Cas9 KO in an authentic human beta cell line (EndoC-βH1). The KO pipeline consists of a dual lentiviral sgRNA strategy and we targeted three genes (INS, IDE, PAM) as a proof of concept. We achieved a significant reduction in mRNA levels and complete protein depletion of all target genes. Using this dual sgRNA strategy, up to 94 kb DNA were cut out of the target genes and the editing efficiency of each sgRNA exceeded >87.5%. Sequencing of off-targets showed no unspecific editing. Most importantly, the pipeline did not affect the glucose-responsive insulin secretion of the cells. Interestingly, comparison of KO cell lines for NEUROD1 and SLC30A8 with siRNA-mediated knockdown (KD) approaches demonstrate phenotypic differences. NEUROD1-KO cells were not viable and displayed elevated markers for ER stress and apoptosis. NEUROD1-KD, however, only had a modest elevation, by 34%, in the pro-apoptotic transcription factor CHOP and a gene expression profile indicative of chronic ER stress without evidence of elevated cell death. On the other hand, SLC30A8-KO cells demonstrated no reduction in KATP channel gene expression in contrast to siRNA silencing. Overall, this strategy to efficiently create stable KO in the human beta cell line EndoC-βH1 will allow for a better understanding of genes involved in beta cell dysfunction, their underlying functional mechanisms and T2D pathogenesis.

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Gene expression analysis of human prostate cell lines with and without tumor metastasis suppressor CD82

BMC Cancer ◽

10.1186/s12885-020-07675-7 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Pushpaja Dodla ◽

Vanitha Bhoopalan ◽

Sok Kean Khoo ◽

Cindy Miranti ◽

Suganthi Sridhar

Keyword(s):

Gene Expression ◽

Cell Line ◽

Cell Lines ◽

Differentially Expressed Genes ◽

Tumor Metastasis ◽

Human Prostate ◽

Metastasis Suppressor ◽

Data Sets ◽

Prostate Cell ◽

Prostate Cell Lines

Abstract Background Tetraspanin CD82 is a tumor metastasis suppressor that is known to down regulate in various metastatic cancers. However, the exact mechanism by which CD82 prevents cancer metastasis is unclear. This study aims to identify genes that are regulated by CD82 in human prostate cell lines. Methods We used whole human genome microarray to obtain gene expression profiles in a normal prostate epithelial cell line that expressed CD82 (PrEC-31) and a metastatic prostate cell line that does not express CD82 (PC3). Then, siRNA silencing was used to knock down CD82 expression in PrEC-31 while CD82 was re-expressed in PC3 to acquire differentially-expressed genes in the respective cell line. Results Differentially-expressed genes with a P < 0.05 were identified in 3 data sets: PrEC-31 (+CD82) vs PrEC-31(−CD82), PC3–57 (+CD82) vs. PC3-5 V (−CD82), and PC3–29 (+CD82) vs. PC3-5 V (−CD82). Top 25 gene lists did not show overlap within the data sets, except (CALB1) the calcium binding protein calbindin 1 which was significantly up-regulated (2.8 log fold change) in PrEC-31 and PC3–29 cells that expressed CD82. Other most significantly up-regulated genes included serine peptidase inhibitor kazal type 1 (SPINK1) and polypeptide N-acetyl galactosaminyl transferase 14 (GALNT14) and most down-regulated genes included C-X-C motif chemokine ligand 14 (CXCL14), urotensin 2 (UTS2D), and fibroblast growth factor 13 (FGF13). Pathways related with cell proliferation and angiogenesis, migration and invasion, cell death, cell cycle, signal transduction, and metabolism were highly enriched in cells that lack CD82 expression. Expression of two mutually inclusive genes in top 100 gene lists of all data sets, runt-related transcription factor (RUNX3) and trefoil factor 3 (TFF3), could be validated with qRT-PCR. Conclusion Identification of genes and pathways regulated by CD82 in this study may provide additional insights into the role that CD82 plays in prostate tumor progression and metastasis, as well as identify potential targets for therapeutic intervention.

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Constitutive expression of SOCS3 confers resistance to IFN-α in chronic myelogenous leukemia cells

Blood ◽

10.1182/blood-2002-01-0073 ◽

2002 ◽

Vol 100 (8) ◽

pp. 2926-2931 ◽

Cited By ~ 67

Author(s):

Ikuya Sakai ◽

Kazuto Takeuchi ◽

Hayato Yamauchi ◽

Hirosi Narumi ◽

Shigeru Fujita

Keyword(s):

Cell Line ◽

Cell Lines ◽

Chronic Myelogenous Leukemia ◽

Blast Crisis ◽

Constitutive Expression ◽

Myelogenous Leukemia ◽

Cytokine Signaling ◽

Interferon Α ◽

Socs3 Expression ◽

Blast Cells

Because suppressor of cytokine signaling (SOCS) proteins are negative regulators of cytokine-induced signaling, it has been hypothesized that aberrant SOCS expression confers resistance against cytokine therapy. This study reports on the constitutive expression of SOCS3 in most chronic myelogenous leukemia (CML) cell lines, which are resistant to treatment with interferon α (IFN-α). In contrast, the KT-1/A3 cell line, in which constitutive expression of SOCS3 is barely detectable, is sensitive to IFN-α treatment. Forced expression of SOCS3 in the KT-1/A3 cell line confers resistance to IFN-α treatment. Furthermore, most of the blast cells from patients in CML blast crisis, which are usually resistant to IFN-α therapy, showed constitutive expression of SOCS3. These findings indicate that constitutive SOCS3 expression affects the IFN-α sensitivity of CML cell lines and blast cells from patients with CML blast crisis.

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Overexpression of thyroid hormone receptor beta1 is associated with thyrotropin receptor gene expression and proliferation in a human thyroid carcinoma cell line

Journal of Endocrinology ◽

10.1677/joe.0.1650379 ◽

2000 ◽

Vol 165 (2) ◽

pp. 379-389 ◽

Cited By ~ 18

Author(s):

ST Chen ◽

HY Shieh ◽

JD Lin ◽

KS Chang ◽

KH Lin

Keyword(s):

Gene Expression ◽

Transcription Factor ◽

Thyroid Hormone ◽

Cell Line ◽

Cell Lines ◽

Hormone Receptor ◽

Thyroid Hormone Receptor ◽

Human Thyroid ◽

Thyrotropin Receptor ◽

Tshr Gene

To correlate the differentiation phenotype of two human thyroid cancer cell lines with their expression of various molecular markers, we analyzed the mRNA levels of four thyroid-specific genes, including thyrotropin receptor (TSHR), thyroglobulin (Tg), thyroid transcription factor-1 (TTF-1), and paired-box containing transcription factor-8 (PAX-8) genes. The results showed a differentiation-status-related pattern in which a well-differentiated cell line (WRO) expressed all the four genes, in contrast to an anaplastic cell line (ARO) that expressed TTF-1 and reduced levels of TSHR, but no Tg or PAX-8 genes. Furthermore, to verify the finding of concomitant loss of beta subtype thyroid hormone receptor (TRbeta) and TSHR gene expression in neoplastic thyroid tumors (Bronnegard et al. 1994), we examined the expression levels of TRbeta1 gene in these cell lines. Whereas the WRO cells produced an abundant amount of TRbeta1 protein detectable by immunoprecipitation, the ARO cells produced none. This new observation prompted us to investigate whether overexpression of TRbeta1 protein in ARO cells might produce changes in the differentiation phenotypes. We found that the level of expression of the TSHR gene and the proliferative index of ARO cells were significantly upregulated in the cells stably transfected with wild-type TRbeta1. These findings suggest that TRbeta1 protein overexpression can affect the differentiation phenotypes and induce more efficient cell proliferation of the anaplastic ARO cells.

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Deregulated Apoptotic Pathways Point to Effectiveness of IAP Inhibitor Therapy in Acute Myeloid Leukemia.

Blood ◽

10.1182/blood.v114.22.1275.1275 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1275-1275

Author(s):

Sonja C Lück ◽

Annika C Russ ◽

Konstanze Döhner ◽

Ursula Botzenhardt ◽

Domagoj Vucic ◽

...

Keyword(s):

Gene Expression ◽

Acute Myeloid Leukemia ◽

Cell Line ◽

Cell Lines ◽

Myeloid Leukemia ◽

Gene Set Enrichment Analysis ◽

Core Binding Factor ◽

Binding Factor ◽

Acute Myeloid

Abstract Abstract 1275 Poster Board I-297 Core binding factor (CBF) leukemias, characterized by translocations t(8;21) or inv(16)/t(16;16) targeting the core binding factor, constitute acute myeloid leukemia (AML) subgroups with favorable prognosis. However, 40-50% of patients relapse, and the current classification system does not fully reflect the heterogeneity existing within the cytogenetic subgroups. Therefore, illuminating the biological mechanisms underlying these differences is important for an optimization of therapy. Previously, gene expression profiling (GEP) revealed two distinct CBF leukemia subgroups displaying significant outcome differences (Bullinger et al., Blood 2007). In order to further characterize these GEP defined CBF subgroups, we again used gene expression profiles to identify cell line models similar to the respective CBF cohorts. Treatment of these cell lines with cytarabine (araC) revealed a differential response to the drug as expected based on the expression patterns reflecting the CBF subgroups. In accordance, the cell lines resembling the inferior outcome CBF cohort (ME-1, MONO-MAC-1, OCI-AML2) were less sensitive to araC than those modeling the good prognostic subgroup (Kasumi-1, HEL, MV4-11). A previous gene set enrichment analysis had identified the pathways Caspase cascade in apoptosis and Role of mitochondria in apoptotic signaling among the most significant differentially regulated BioCarta pathways distinguishing the two CBF leukemia subgroups. Thus, we concluded that those pathways might be interesting targets for specific intervention, as deregulated apoptosis underlying the distinct subgroups should also result in a subgroup specific sensitivity to apoptotic stimuli. Therefore, we treated our model cell lines with the Smac mimetic BV6, which antagonizes inhibitor of apoptosis (IAP) proteins that are differentially expressed among our CBF cohorts. In general, sensitivity to BV6 treatment was higher in the cell lines corresponding to the subgroup with good outcome. Time-course experiments with the CBF leukemia cell line Kasumi-1 suggested a role for caspases in this response. Interestingly, combination treatment of araC and BV6 in Kasumi-1 showed a synergistic effect of these drugs, with the underlying mechanisms being currently further investigated. Based on the promising sensitivity to BV6 treatment in some cell lines, we next treated mononuclear cells (mostly leukemic blasts) derived from newly diagnosed AML patients with BV6 in vitro to evaluate BV6 potency in primary leukemia samples. Interestingly, in vitro BV6 treatment also discriminated AML cases into two distinct populations. Most patient samples were sensitive to BV6 monotherapy, but about one-third of cases were resistant even at higher BV6 dosage. GEP of BV6 sensitive patients (at 24h following either BV6 or DMSO treatment) provided insights into BV6-induced pathway alterations in the primary AML patient samples, which included apoptosis-related pathways. In contrast to the BV6 sensitive patients, GEP analyses of BV6 resistant cases revealed no differential regulation of apoptosis-related pathways in this cohort. These results provide evidence that targeting deregulated apoptosis pathways by Smac mimetics might represent a promising new therapeutic approach in AML and that GEP might be used to predict response to therapy, thereby enabling novel individual risk-adapted therapeutic approaches. Disclosures Vucic: Genentech, Inc.: Employment. Deshayes:Genentech, Inc.: Employment.

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A Novel Microarray Gene Expression Analysis of Murine AML Cell Lines Provides Clues to the Development of Drug Resistance to Ara-C

Blood ◽

10.1182/blood.v112.11.5017.5017 ◽

2008 ◽

Vol 112 (11) ◽

pp. 5017-5017

Author(s):

Susan K Rathe ◽

David Largaespada

Keyword(s):

Gene Expression ◽

Cell Line ◽

Cell Lines ◽

Ribosomal Subunit ◽

Nuclear Factor Κb ◽

Parental Cell ◽

Parental Cell Line ◽

Drug Resistant ◽

Microarray Gene Expression ◽

Expression Microarrays

Abstract Acute myeloid leukemia (AML) has the ability to evade cell death in the presence of chemotherapeutic cocktails containing cytosine arabinoside (Ara-C). This lab previously developed two highly resistant murine AML cell lines, B117H and B140H, by introducing increasing concentrations of Ara-C to their parental cell lines, B117P and B140P, respectively. B117H and B140H can tolerate Ara-C concentrations ~1000X that of their drug sensitive parental cell lines. mRNA from all four cell lines were used in gene expression microarrays for the purpose of comparing Ara-C drug resistant murine AML cell lines with their Ara-C drug sensitive parental lines. A novel algorithm was developed to evaluate the changes in gene expression between the drug resistant and drug sensitive cells. The algorithm differed from more conventional algorithms in two key ways. First, the detection data was normalized by using ribosomal subunit 9 (Rsp9) as the normalization gene, and secondly it calculated fold change by comparing the minimum value of one population to the maximum value of the other population. The output of this algorithm was a list of genes with significant gene expression changes. These genes were next submitted to the Ingenuity Pathway Analysis (IPA) process. IPA implicated nuclear factor-κB (NFκB) in the Ara-C resistance process. Cell growth assays confirmed that the Ara-C drug resistant B117H cell line was significantly more sensitive to NFκB inhibition than its Ara-C sensitive parental cell line. This leads us to believe that the selection of Ara-C resistance may also concomitantly make some AML cells highly sensitive to killing by NFκB inhibition. This theory is being tested further through the use of drug combination assays, to determine if a synergistic or antagonistic relationship exists between Ara-C and various drugs that affect the NFκB pathway.

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Connecting gene expression subtypes of colorectal cancer (CRC) with cell lines and drug resistance.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.e14544 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. e14544-e14544

Author(s):

Eva Budinska ◽

Jenny Wilding ◽

Vlad Calin Popovici ◽

Edoardo Missiaglia ◽

Arnaud Roth ◽

...

Keyword(s):

Gene Expression ◽

Cell Line ◽

Clinical Significance ◽

Cell Lines ◽

Drug Response ◽

Drug Sensitivity ◽

Expression Profiles ◽

Enrichment Analysis ◽

Gene Set Enrichment Analysis

e14544 Background: We identified CRC gene expression subtypes (ASCO 2012, #3511), which associate with established parameters of outcome as well as relevant biological motifs. We now substantiate their biological and potentially clinical significance by linking them with cell line data and drug sensitivity, primarily attempting to identify models for the poor prognosis subtypes Mesenchymal and CIMP-H like (characterized by EMT/stroma and immune-associated gene modules, respectively). Methods: We analyzed gene expression profiles of 35 publicly available cell lines with sensitivity data for 82 drug compounds, and our 94 cell lines with data on sensitivity for 7 compounds and colony morphology. As in vitro, stromal and immune-associated genes loose their relevance, we trained a new classifier based on genes expressed in both systems, which identifies the subtypes in both tissue and cell cultures. Cell line subtypes were validated by comparing their enrichment for molecular markers with that of our CRC subtypes. Drug sensitivity was assessed by linking original subtypes with 92 drug response signatures (MsigDB) via gene set enrichment analysis, and by screening drug sensitivity of cell line panels against our subtypes (Kruskal-Wallis test). Results: Of the cell lines 70% could be assigned to a subtype with a probability as high as 0.95. The cell line subtypes were significantly associated with their KRAS, BRAF and MSI status and corresponded to our CRC subtypes. Interestingly, the cell lines which in matrigel created a network of undifferentiated cells were assigned to the Mesenchymal subtype. Drug response studies revealed potential sensitivity of subtypes to multiple compounds, in addition to what could be predicted based on their mutational profile (e.g. sensitivity of the CIMP-H subtype to Dasatinib, p<0.01). Conclusions: Our data support the biological and potentially clinical significance of the CRC subtypes in their association with cell line models, including results of drug sensitivity analysis. Our subtypes might not only have prognostic value but might also be predictive for response to drugs. Subtyping cell lines further substantiates their significance as relevant model for functional studies.

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The role of HNF4A in GATA4-deficiency phenotypes of hepatocellular carcinoma.

Journal of Clinical Oncology ◽

10.1200/jco.2018.36.4_suppl.284 ◽

2018 ◽

Vol 36 (4_suppl) ◽

pp. 284-284

Author(s):

Yu Bin Tan ◽

Timothy Shuen ◽

Han Chong Toh

Keyword(s):

Gene Expression ◽

Hepatocellular Carcinoma ◽

Cell Cycle ◽

Correlation Analysis ◽

Cell Cycle Arrest ◽

Cell Line ◽

Transgenic Mouse ◽

Cell Lines ◽

Downstream Target ◽

Cycle Arrest

284 Background: Hepatocellular carcinoma (HCC) is the 2nd leading global cause of cancer death. Recently, we have discovered previously undescribed deletion and germline mutation of GATA4 and showed that GATA4 is a key differentiation driver and metabolic regulator in HCC. However, as GATA4 is mostly deleted in HCC, targeting GATA4-downstream molecules is ideal. In this study, proof-of-concept experiments were conducted to show that introduction of HNF4A, which is a GATA4-regulated downstream target, could partially rescue the impaired phenotypes in GATA4-deficient HCC cell line. Methods: Correlation analysis using gene expression microarray of human HCC samples was conducted to identify the genes that are positively correlated with GATA4. A transgenic mouse model with a liver-specific conditional GATA4 knockout was designed to identify liver morphology and gene expression changes which are correlated with the loss of Gata4 in the mouse liver. CRISPR-mediated knockout of GATA4 and lentiviral HNF4A overexpression was carried out in a GATA4-deficient HCC cell lines, PLC/PRF/5 and Hep3B, followed by proliferation, apoptosis, cell cycle and senescence functional assays. Results: Pearson correlation analysis from human HCC samples showed that expression of HNF4A is positively correlated with that of GATA4. Livers from conditional Gata4 knockout mice had lower Hnf4a gene expression when compared to age-matched control mice. Loss of function analysis by CRISPR-mediated GATA4 knockout further showed downregulation of HNF4A in GATA4-deficient PLC/PRF/5 cell line. Lentiviral HNF4A overexpression in PLC/PRF/5 and Hep3B demonstrated reduced proliferation and increased apoptosis while PLC/PRF/5 also showed cell cycle arrest at G2/M phase when compared to control. However, no senescence induction was detected in HNF4A-overexpressing cells. Conclusions: Transgenic mouse data, CRISPR-mediated knockout and analysis of HCC samples showed that HNF4A is a key GATA4-downstream target. HNF4A overexpression decreases proliferation, increases apoptosis and cell cycle arrest in GATA4-deficient HCC cell lines, thus representing a possible therapeutic target for HCC.

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