FOXA1/MND1/TKT axis regulates gastric cancer progression and oxaliplatin sensitivity via PI3K/AKT signaling pathway.

BACKGROUND: Drug resistance is a main factor affecting the chemotherapy efficacy of gastric cancer (GC), in which meiosis plays an important role. Therefore, it is urgent to explore the effect of meiosis related genes on chemotherapy resistance. METHODS: The expression of meiotic nuclear divisions 1 (MND1) in GC was detected by using TCGA and clinical specimens. In vitro and in vivo assays were used to investigate the effects of MND1. The molecular mechanism was determined using luciferase reporter assay, CO-IP and mass spectrometry (MS). RESULTS: Through bioinformatics, we found that MND1 was highly expressed in platinum-resistant samples. In vitro experiments showed that interference of MND1 significantly inhibited the progression of GC and increased the sensitivity to oxaliplatin. MND1 was significantly higher in 159 GC tissues in comparison with the matched adjacent normal tissues. In addition, overexpression of MND1 was associated with worse survival, advanced TNM stage, and lower pathological grade in patients with GC. Further investigation revealed that forkhead box protein A1 (FOXA1) directly binds to the promoter of MND1 to inhibit its transcription. CO-IP and MS assays showed that MND1 was coexpressed with transketolase (TKT). In addition,TKT activated the PI3K/AKT signaling axis and enhanced the glucose uptake and lactate production in GC cells. CONCLUSIONS: Our results confirm that FOXA1 inhibits the expression of MND1, which can directly bind to TKT to promote GC progression and reduce oxaliplatin sensitivity through the PI3K/AKT signaling pathway.

High FOXA1 levels induce ER transcriptional reprogramming, a pro-metastatic secretome, and metastasis in endocrine-resistant breast cancer.

Aberrant activation of the forkhead protein FOXA1 is observed in advanced hormone-related cancers. However, the key mediators of high FOXA1 signaling remain elusive. We demonstrate that ectopic high FOXA1 (H-FOXA1) expression promotes estrogen receptor-positive (ER+) breast cancer (BC) metastasis in a xenograft mouse model. Mechanistically, H-FOXA1 reprograms ER-chromatin binding to elicit a core gene signature (CGS) enriched in ER+ endocrine-resistant (EndoR) cells. We identify Secretome14, a CGS subset encoding ER-dependent cancer secretory proteins, as a strong predictor for poor outcomes of ER+ BC. It is elevated in ER+ metastases vs. primary tumors, irrespective of ESR1 mutations. Genomic ER binding near Secretome14 genes is also increased in mutant ER-expressing or mitogen-treated ER+ BC cells and in ER+ metastatic vs. primary tumors, suggesting a convergent pathway including high growth factor receptor signaling in activating pro-metastatic secretome genes. Our findings uncover H-FOXA1-induced ER reprogramming that drives EndoR and metastasis partly via an H-FOXA1/ER-dependent secretome.

FOXA1 in prostate cancer.

Most prostate cancers initially respond to androgen deprivation therapy (ADT). With the long-term application of ADT, localized prostate cancer will progress to castration-resistant prostate cancer (CRPC), metastatic CRPC (mCRPC), and neuroendocrine prostate cancer (NEPC), and the transcriptional network shifted. Forkhead box protein A1 (FOXA1) may play a key role in this process through multiple mechanisms. To better understand the role of FOXA1 in prostate cancer, we review the interplay among FOXA1-targeted genes, modulators of FOXA1, and FOXA1 with a particular emphasis on androgen receptor (AR) function. Furthermore, we discuss the distinct role of FOXA1 mutations in prostate cancer and clinical significance of FOXA1. We summarize possible regulation pathways of FOXA1 in different stages of prostate cancer. We focus on links between FOXA1 and AR, which may play different roles in various types of prostate cancer. Finally, we discuss FOXA1 mutation and its clinical significance in prostate cancer. FOXA1 regulates the development of prostate cancer through various pathways, and it could be a biomarker for mCRPC and NEPC. Future efforts need to focus on mechanisms underlying mutation of FOXA1 in advanced prostate cancer. We believe that FOXA1 would be a prognostic marker and therapeutic target in prostate cancer.

FOXA1 in prostate cancer / 亚洲男科学杂志(英文版)

Most prostate cancers initially respond to androgen deprivation therapy (ADT). With the long-term application of ADT, localized prostate cancer will progress to castration-resistant prostate cancer (CRPC), metastatic CRPC (mCRPC), and neuroendocrine prostate cancer (NEPC), and the transcriptional network shifted. Forkhead box protein A1 (FOXA1) may play a key role in this process through multiple mechanisms. To better understand the role of FOXA1 in prostate cancer, we review the interplay among FOXA1-targeted genes, modulators of FOXA1, and FOXA1 with a particular emphasis on androgen receptor (AR) function. Furthermore, we discuss the distinct role of FOXA1 mutations in prostate cancer and clinical significance of FOXA1. We summarize possible regulation pathways of FOXA1 in different stages of prostate cancer. We focus on links between FOXA1 and AR, which may play different roles in various types of prostate cancer. Finally, we discuss FOXA1 mutation and its clinical significance in prostate cancer. FOXA1 regulates the development of prostate cancer through various pathways, and it could be a biomarker for mCRPC and NEPC. Future efforts need to focus on mechanisms underlying mutation of FOXA1 in advanced prostate cancer. We believe that FOXA1 would be a prognostic marker and therapeutic target in prostate cancer.

[MicroRNA-30a inhibits proliferation of hepatocellular carcinoma cells via targeted regulation of forkhead-box protein A1].

Objective: To investigate the expression of microRNA-30a (miR-30a) in hepatocellular carcinoma (HCC) and related molecular mechanisms in regulating HCC cell proliferation. Methods: A total of 30 pairs of HCC and adjacent tissue samples were collected, and quantitative real-time PCR and Western blot were used to measure the mRNA and protein expression of forkhead-box protein A1 (FOXA1). Methyl thiazolyl tetrazolium (MTT) assay was used to evaluate the proliferation of HCC cells, luciferase reporter gene assay was performed to verify the target relationship between miR-30a and FOXA1, and MTT assay and Western blot were used to measure the proliferation of HepG2 cells and the protein expression of FOXA1 after miR-30a transfection. The t-test was used for comparison of data between two groups, and a one-way analysis of variance was used for comparison of data between multiple groups. P < 0.05 was considered statistically significant. Results: HCC tissue had significantly lower relative expression of miR-30a than adjacent tissue (1.049 ± 0.380 vs 1.982 ± 1.013, t = 3.985, P < 0.001). At 72 hours after miR-30a overexpression, there was a significant difference in the proliferative capacity of HepG2 cells between the blank control group, the miR-30a-NC group, and the miR-30a group (0.821 ± 0.006 vs 0.816 ± 0.013 vs 0.546 ± 0.020, F = 3.396, P < 0.05), suggesting that miR-30a overexpression significantly inhibited the proliferation of HepG2 cells. FOXA1 was a target gene of miR-30a and its protein expression was negatively regulated by miR-30a, and there was a significant difference in luciferase activity between wild-type and mutant FOXA1-3'UTR vectors (1.221 ± 0.024 vs 2.658 ± 0.031, F = 6.737, P < 0.05). In HepG2 cells, miR-30a overexpression significantly inhibited the protein expression of FOXA1, and there was a significant difference in the relative expression of FOXA1 between the blank control group, the miR-30a-NC group, and the miR-30a group (1.019 ± 0.016 vs 1.022 ± 0.017 vs 0.227 ± 0.021, F = 45.43, P < 0.05). Upregulating the protein expression of FOXA1 reversed the inhibitory effect of miR-30a on the proliferation of HepG2 cells, and there was a significant difference in the proliferative capacity of HepG2 cells between the miR-30a group and the miR-30a+FOXA1 group (0.524 ± 0.023 vs 0.843 ± 0.019, t = 2.507, P < 0.05). Conclusion: MiR-30a exerts its inhibitory effect on the proliferation of HCC cells by negatively regulating the expression of FOXA1.

FOXA1 Induces E-Cadherin Expression at the Protein Level via Suppression of Slug in Epithelial Breast Cancer Cells.

Epithelial-to-mesenchymal transition (EMT) is an important process during embryonic development and tumor progression by which adherent epithelial cells acquire mesenchymal properties. Forkhead box protein A1 (FOXA1) is a transcriptional regulator preferentially expressed in epithelial breast cancer cells, and its expression is lost in mesenchymal breast cancer cells. However, the implication of this biased expression of FOXA1 in breast cancer is not fully understood. In this study, we analyzed the involvement of FOXA1 in EMT progression in breast cancer, and found that stable expression of FOXA1 in the mesenchymal breast cancer MDA-MB-231 cells strongly induced the epithelial marker E-cadherin at the mRNA and protein levels. Furthermore, stable expression of FOXA1 was found to reduce the mRNA and protein expression of Slug, a repressor of E-cadherin expression. FOXA1 knockdown in the epithelial breast cancer MCF7 cells reduced E-cadherin protein expression without decreasing its mRNA expression. In addition, FOXA1 knockdown in MCF7 cells up-regulated Slug mRNA and protein expression. Notably, similar to FOXA1 knockdown, stable expression of Slug in MCF7 cells reduced E-cadherin protein expression without decreasing its mRNA expression. Taken together, these results suggest that although FOXA1 can induce E-cadherin mRNA expression, it preferentially promotes E-cadherin expression at the protein level by suppressing Slug expression in epithelial breast cancer, and that the balance of this FOXA1-Slug axis regulates EMT progression.

MicroRNA-30a inhibits proliferation of hepatocellular carcinoma cells via targeted regulation of forkhead-box protein A1 / 中华肝脏病杂志

Objective@#To investigate the expression of microRNA-30a (miR-30a) in hepatocellular carcinoma (HCC) and related molecular mechanisms in regulating HCC cell proliferation.@*Methods@#A total of 30 pairs of HCC and adjacent tissue samples were collected, and quantitative real-time PCR and Western blot were used to measure the mRNA and protein expression of forkhead-box protein A1 (FOXA1). Methyl thiazolyl tetrazolium (MTT) assay was used to evaluate the proliferation of HCC cells, luciferase reporter gene assay was performed to verify the target relationship between miR-30a and FOXA1, and MTT assay and Western blot were used to measure the proliferation of HepG2 cells and the protein expression of FOXA1 after miR-30a transfection. The t-test was used for comparison of data between two groups, and a one-way analysis of variance was used for comparison of data between multiple groups. P < 0.05 was considered statistically significant.@*Results@#HCC tissue had significantly lower relative expression of miR-30a than adjacent tissue (1.049 ± 0.380 vs 1.982 ± 1.013, t = 3.985, P < 0.001). At 72 hours after miR-30a overexpression, there was a significant difference in the proliferative capacity of HepG2 cells between the blank control group, the miR-30a-NC group, and the miR-30a group (0.821 ± 0.006 vs 0.816 ± 0.013 vs 0.546 ± 0.020, F = 3.396, P < 0.05), suggesting that miR-30a overexpression significantly inhibited the proliferation of HepG2 cells. FOXA1 was a target gene of miR-30a and its protein expression was negatively regulated by miR-30a, and there was a significant difference in luciferase activity between wild-type and mutant FOXA1-3’UTR vectors (1.221 ± 0.024 vs 2.658 ± 0.031, F = 6.737, P < 0.05). In HepG2 cells, miR-30a overexpression significantly inhibited the protein expression of FOXA1, and there was a significant difference in the relative expression of FOXA1 between the blank control group, the miR-30a-NC group, and the miR-30a group (1.019 ± 0.016 vs 1.022 ± 0.017 vs 0.227 ± 0.021, F = 45.43, P < 0.05). Upregulating the protein expression of FOXA1 reversed the inhibitory effect of miR-30a on the proliferation of HepG2 cells, and there was a significant difference in the proliferative capacity of HepG2 cells between the miR-30a group and the miR-30a+FOXA1 group (0.524 ± 0.023 vs 0.843 ± 0.019, t = 2.507, P < 0.05).@*Conclusion@#MiR-30a exerts its inhibitory effect on the proliferation of HCC cells by negatively regulating the expression of FOXA1.

Clinicopathological significance of forkhead box protein A1 in breast cancer: A meta-analysis.

The aim of the present study was to investigate the associations between the expression of forkhead box protein A1 (FOXA1) and differential clinicopathological characteristics in breast cancer using a meta-analysis method. Eligible studies that investigated the correlation between FOXA1 expression and the clinical characteristics of breast cancer were collected through searching numerous databases, including PubMed, EMBASE, the Chinese National Knowledge Infrastructure and the VIP database. In total, eight studies were included in the meta-analysis. Following a systematic analysis, the expression of FOXA1 was found to be significantly associated with the estrogen receptor α status, the progesterone receptor status, lymph node metastasis and the histological grade in breast cancer. However, no statistically significant association was observed between FOXA1 expression and the human epidermal growth factor receptor-2 status in breast cancer patients.

MicroRNA-212 targets FOXA1 and suppresses the proliferation and invasion of intrahepatic cholangiocarcinoma cells.

MicroRNAs (miRNAs), which are a class of small RNAs, have been shown to negatively regulate the expression of their target genes by directly binding to the 3'-untranslated region (3'-UTR) of mRNA. miRNA dysregulation has been associated with the pathogenesis of numerous types of human cancer. However, the role of miRNAs in intrahepatic cholangiocarcinoma (ICC) has yet to be fully elucidated. The present study aimed to investigate the role of miR-212 in the growth and metastasis of ICC in vitro, as well as the underlying mechanism. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to examine mRNA and protein expression. An MTT assay and transwell assay were conducted to determine cell proliferation and invasion rates. The results of the RT-qPCR demonstrated that miR-212 was downregulated in the majority of investigated ICC tissues, as compared with their matched adjacent non-tumor tissues. In addition, miR-212 expression was shown to be markedly downregulated in three ICC cell lines, as compared with human intrahepatic biliary epithelial cells. Furthermore, restoration of miR-212 expression significantly suppressed the proliferation and invasion of ICC QBC939 cells. Forkhead box protein A1 (FOXA1) was predicted to be a putative target of miR-212 by bioinformatics analysis with TargetScan. Therefore, a luciferase reporter assay was conducted to confirm that miR-212 was able to directly bind to the 3'-UTR of FOXA1 mRNA. In addition, using western blot analysis, the protein expression of FOXA1 was shown to be negatively regulated by miR-212 in ICC QBC939 cells. In conclusion, it was demonstrated that FOXA1 was frequently upregulated in various ICC tissues and cell lines. The results of the present study suggested that miR-212 inhibits the proliferation and invasion of ICC cells by directly targeting FOXA1, and thus may be considered a potential candidate for the treatment of ICC.

MicroRNA-212 suppresses the proliferation and migration of osteosarcoma cells by targeting forkhead box protein A1.

MicroRNAs (miRNAs) are a class of small non-coding RNAs that function as critical gene regulators by targeting the 3' untranslated region (UTR) of mRNA, causing translational repression or mRNA degradation. Deregulation of specific miRNAs, including miR-212, has been identified in patients with osteosarcoma. However, the underlying mechanism is yet to be fully elucidated. The present study aimed to reveal the regulatory mechanism of miR-212 in osteosarcoma cell viability and migration. Quantitative polymerase chain reaction data revealed that miR-212 was significantly downregulated in osteosarcoma tissues compared with normal bone tissues. miR-212 was also downregulated in osteosarcoma cell lines compared with normal osteoblast cell lines. Overexpression of miR-212 significantly suppressed the viability and migration of human osteosarcoma MG-63 and Saos-2 cell lines. In addition, forkhead box protein A1 (FOXA1), an oncogene in osteosarcoma, was predicted to be a putative target of miR-212 by bioinformatical analysis. Furthermore, luciferase reporter assay data confirmed that miR-212 could directly bind to the seed sequences within the 3'UTR of FOXA1 mRNA, and miR-212 negatively mediated the protein levels of FOXA1 in osteosarcoma MG-63 and Saos-2 cells. Moreover, knockdown of FOXA1 also led to a significant decrease in the viability and migration of osteosarcoma MG-63 and Saos-2 cells and the expression levels of FOXA1 were significantly upregulated in osteosarcoma tissues and cell lines. These data suggest that miR-212 inhibits the viability and migration of osteosarcoma cells by targeting FOXA1. Accordingly, miR-212 may become a potential candidate for osteosarcoma therapy.

Lipid-rich diet enhances L-cell density in obese subjects and in mice through improved L-cell differentiation.

The enterohormone glucagon-like peptide-1 (GLP-1) is required to amplify glucose-induced insulin secretion that facilitates peripheral glucose utilisation. Alteration in GLP-1 secretion during obesity has been reported but is still controversial. Due to the high adaptability of intestinal cells to environmental changes, we hypothesised that the density of GLP-1-producing cells could be modified by nutritional factors to prevent the deterioration of metabolic condition in obesity. We quantified L-cell density in jejunum samples collected during Roux-en-Y gastric bypass in forty-nine severely obese subjects analysed according to their fat consumption. In mice, we deciphered the mechanisms by which a high-fat diet (HFD) makes an impact on enteroendocrine cell density and function. L-cell density in the jejunum was higher in obese subjects consuming >30 % fat compared with low fat eaters. Mice fed a HFD for 8 weeks displayed an increase in GLP-1-positive cells in the jejunum and colon accordingly to GLP-1 secretion. The regulation by the HFD appears specific to GLP-1-producing cells, as the number of PYY (peptide YY)-positive cells remained unchanged. Moreover, genetically obese ob/ob mice did not show alteration of GLP-1-positive cell density in the jejunum or colon, suggesting that obesity per se is not sufficient to trigger the mechanism. The higher L-cell density in HFD-fed mice involved a rise in L-cell terminal differentiation as witnessed by the increased expression of transcription factors downstream of neurogenin3 (Ngn3). We suggest that the observed increase in GLP-1-positive cell density triggered by high fat consumption in humans and mice might favour insulin secretion and therefore constitute an adaptive response of the intestine to balance diet-induced insulin resistance.