Integrative multi-omics analysis of intestinal organoid differentiation.

Intestinal organoids accurately recapitulate epithelial homeostasis in vivo, thereby representing a powerful in vitro system to investigate lineage specification and cellular differentiation. Here, we applied a multi-omics framework on stem cell-enriched and stem cell-depleted mouse intestinal organoids to obtain a holistic view of the molecular mechanisms that drive differential gene expression during adult intestinal stem cell differentiation. Our data revealed a global rewiring of the transcriptome and proteome between intestinal stem cells and enterocytes, with the majority of dynamic protein expression being transcription-driven. Integrating absolute mRNA and protein copy numbers revealed post-transcriptional regulation of gene expression. Probing the epigenetic landscape identified a large number of cell-type-specific regulatory elements, which revealed Hnf4g as a major driver of enterocyte differentiation. In summary, by applying an integrative systems biology approach, we uncovered multiple layers of gene expression regulation, which contribute to lineage specification and plasticity of the mouse small intestinal epithelium.

HNF4G increases cisplatin resistance in lung adenocarcinoma via the MAPK6/Akt pathway.

Background: Lung adenocarcinoma is one of the most common tumors, and cisplatin is frequently used in treating lung adenocarcinoma patients. This study aimed to look into the roles and mechanisms of HNF4G in cisplatin resistance of lung adenocarcinoma. Materials & Methods: Cisplatin resistance and gene expression data of 542 cell lines from the CTRP and CCLE databases were analyzed. HNF4G expression was detected in the lung adenocarcinoma cell lines after treatment with various concentrations of cisplatin. Cisplatin sensitivity curves were detected in cells that overexpressed or knocked down HNF4G. The ChIP-Seq data were then analyzed to identify the targets of HNF4G involved in cisplatin resistance. Expression and phosphorylation of the MAPK6/Akt pathway were detected after HNF4G was overexpressed or knocked down. Finally, ChIP-qPCR and dual-luciferase assays were used to investigate the regulation of HNF4G on MAPK6. Results: In cell lines, high expression of HNF4G was significantly positively correlated with cisplatin resistance, and lung adenocarcinoma patients who had high HNF4G expression had a poor prognosis. Cisplatin treatment increased HNF4G expression, and overexpression of HNF4G significantly increased the resistance to cisplatin in A549 and HCC827 cells, whereas knockdown of HNF4G had the opposite effect. HNF4G overexpression increased MAPK6 expression and activated the MAPK6/Akt pathway, while an Akt inhibitor reduced the effects of HNF4G on cisplatin resistance. HNF4G bound to the MAPK6 promoter region, promoting MAPK6 expression, according to ChIP-qPCR and luciferase assays. Conclusion: By binding to the MAPK6 promoter region, HNF4G promotes MAPK6 expression and subsequent Akt phosphorylation, resulting in resistance to cisplatin in lung adenocarcinoma.

HNF4G stimulates the development of pancreatic cancer by promoting IGF2BP2 transcription.

OBJECTIVE: Pancreatic cancer is a devastating and lethal malignancy. Our study investigated the effective mechanism of HNF4G on pancreatic cancer cell functions through the IGF2BP2 transcription. METHODS: HNF4G and IGF2BP2 expressions in pancreatic cancer were examined. The relationship between HNF4G expression and pancreatic cancer patients' clinicopathological characteristics was evaluated. After interfering with HNF4G expression in pancreatic cancer cells, the cell proliferative, migratory, and invasive capabilities were evaluated. Also, the expression of proliferation-related gene PCNA and migration and invasion-related gene MMP2 was determined. The binding relation between HNF4G and HNF4G promoter was forecasted and testified. A tumorigenesis assay in nude mice was performed to detect the HNF4G interference's effect on the subcutaneous tumorigenic capacity of pancreatic cancer cells. RESULTS: HNF4G and IGF2BP2 expressions were up-regulated in pancreatic cancer. Specifically, interfering with HNF4G inhibited PANC-1 cell proliferative, invasive and migratory behaviors, and decreased PCNA and MMP2 expression. Mechanistically, HNF4G as a transcription factor could specifically bind to IGF2BP2 and promote its expression. Rescue assay findings showed that IGF2BP2 overexpression could reverse the inhibiting effect of HNF4G interference on pancreatic cancer cells. For the in vivo finding, interfering HNF4G expression retarded the subcutaneous tumorigenic ability of pancreatic cancer cells. CONCLUSION: We summarize that HNF4G as a transcription factor regulates IGF2BP2 expression to promote pancreatic cancer cell proliferation and migration capacities.

Hepatocyte nuclear factor 4 gamma (HNF4G) is correlated with poor prognosis and promotes tumor cell growth by inhibiting caspase-dependent intrinsic apoptosis in colorectal cancer.

The hepatocyte nuclear factor 4 gamma (HNF4G), a member of orphan nuclear receptors, is up-regulated and functions as an oncoprotein in a variety of tumors. Recent advances in understanding the biologic function and action mechanism of HNF4G in colorectal cancer (CRC) have not been fully elucidated. In the present study, we observed that HNF4G expression levels were significantly increased in CRC tissues compared with adjacent normal tissues, and HNF4G overexpression correlated with worse prognosis in colorectal cancer. Transfection with a small interference RNA (siRNA) targeting HNF4G in HCT116 and SW480 CRC cell lines significantly inhibited cell proliferation and promoted apoptosis in vitro. In contrast, overexpression of HNF4G increased cell proliferation and decreased the percentage of apoptotic cells. Moreover, we discovered that HNF4G was involved in CRC cell apoptosis via the caspase-dependent intrinsic pathway. Finally, knockdown of HNF4G expression led to attenuated colorectal cancer growth and promoted apoptosis in a xenograft mouse model. Collectively, these results indicate that HNF4G exerts as an oncogenic role in colorectal cancer and provides a potential therapeutic target.

Metformin inhibits pancreatic cancer metastasis caused by SMAD4 deficiency and consequent HNF4G upregulation.

Pancreatic ductal adenocarcinoma (PDAC) has poor prognosis due to limited therapeutic options. This study examines the roles of genome-wide association study identified PDAC-associated genes as therapeutic targets. We have identified HNF4G gene whose silencing most effectively repressed PDAC cell invasiveness. HNF4G overexpression is induced by the deficiency of transcriptional factor and tumor suppressor SMAD4. Increased HNF4G are correlated with SMAD4 deficiency in PDAC tumor samples and associated with metastasis and poor survival time in xenograft animal model and in patients with PDAC (log-rank P = 0.036; HR = 1.60, 95% CI = 1.03-2.47). We have found that Metformin suppresses HNF4G activity via AMPK-mediated phosphorylation-coupled ubiquitination degradation and inhibits in vitro invasion and in vivo metastasis of PDAC cells with SMAD4 deficiency. Furthermore, Metformin treatment significantly improve clinical outcomes and survival in patients with SMAD4-deficient PDAC (log-rank P = 0.022; HR = 0.31, 95% CI = 0.14-0.68) but not in patients with SMAD4-normal PDAC. Pathway analysis shows that HNF4G may act in PDAC through the cell-cell junction pathway. These results indicate that SMAD4 deficiency-induced overexpression of HNF4G plays a critical oncogenic role in PDAC progression and metastasis but may form a druggable target for Metformin treatment.

Expression of HNF4G and its potential functions in lung cancer.

The hepatocyte nuclear factor 4 gamma (HNF4G), a member of orphan nuclear receptors, is up-regulated and functions as an oncoprotein in bladder cancer. In the present study, we observed that HNF4G expression was elevated in lung cancer tissues as compared to adjacent normal lung tissues. The expression of HNF4G protein was correlated with the tumor size and the prognosis of patients. Transfection with a small interference RNA (siRNA) targeting HNF4G in two lung cancer cell lines (H358 and H292 cells) significantly inhibited cell proliferation via arresting cells at G1 phase and inducing cell apoptosis. In addition, HNF4G siRNA reduced cell proliferation in a xenograft tumor-bearing model. Moreover, A549 cells, which had relative lower level of HNF4G, were ectopic expressed with HNF4G and treated with an AKT inhibitor (MK-2206). MK-2206 exposure not only attenuated the promoting effects of HNF4G overexpression on cell proliferation and cell cycle progression, but also suppressed the inhibitory effects of HNF4G overexpression on cell apoptosis. These data suggested that AKT signaling pathway was a potential upstream mediator of HNF4G. Collectively, our data indicate that HNF4G exerts as an oncogenic role in lung cancer by promoting cell proliferation and that HNF4G expression is a potential prognosis factor for lung cancer.

TT genotype of rs2941484 in the human HNF4G gene is associated with hyperuricemia in Chinese Han men.

The aim of the study is to investigate the association between the human hepatocyte nuclear factor 4 gamma (HNF4G) gene and hyperuricemia in Chinese Han population. A total of 414 hyperuricemia patients and 406 gender and age-matched normouricemic controls were enrolled. Four single nucleotide polymorphisms were genotyped as genetic markers for the human HNF4G gene (rs2977939, rs1805098, rs2941484, rs4735692). Data were analyzed for two separate groups: men and women. For rs2941484, the genotype distribution frequency in hyperuricemic subjects and was significantly different from that in normouricemic controls in men (P = 0.038). Meanwhile, in recessive model of rs2941484, the distribution frequency of TT genotype and CC+CT genotypes also differed significantly between the hyperuricemia men and normouricemic men (P = 0.011). For the other 3 SNPs in both men and women, there was no difference in the genotype and allele and distribution frequency between the hyperuricemia patients and normouricemic controls. In men, after adjustments for BMI, SBP, DBP, fasting glucose, total cholesterol, triglycerides, low density lipoprotein cholesterol and creatinine, the men with the TT genotype of rs2941484 were found to have significantly higher probability of suffering from hyperuricemia than the ones with CT and CC genotypes (OR = 2.170, P < 0.001). Therefore, TT genotype of rs2941484 in the human HNF4G gene might be a gender-specific genetic marker for hyperuricemia in Chinese Han men.

Aberrant Activation of a Gastrointestinal Transcriptional Circuit in Prostate Cancer Mediates Castration Resistance.

Prostate cancer exhibits a lineage-specific dependence on androgen signaling. Castration resistance involves reactivation of androgen signaling or activation of alternative lineage programs to bypass androgen requirement. We describe an aberrant gastrointestinal-lineage transcriptome expressed in ∼5% of primary prostate cancer that is characterized by abbreviated response to androgen-deprivation therapy and in ∼30% of castration-resistant prostate cancer. This program is governed by a transcriptional circuit consisting of HNF4G and HNF1A. Cistrome and chromatin analyses revealed that HNF4G is a pioneer factor that generates and maintains enhancer landscape at gastrointestinal-lineage genes, independent of androgen-receptor signaling. In HNF4G/HNF1A-double-negative prostate cancer, exogenous expression of HNF4G at physiologic levels recapitulates the gastrointestinal transcriptome, chromatin landscape, and leads to relative castration resistance.