Downregulation of homeobox gene Barx2 increases gastric cancer proliferation and metastasis and predicts poor patient outcomes

BarH-Like Homeobox 2 Suppresses Cell Proliferation, Invasion, and Angiogenesis in Hepatocellular Carcinoma by Activating N-Acetylgalactosaminyltransferase 4

BarH-like homeobox 2 (BARX2) has been identified to play a key role in the development of multiple cancers. Meanwhile, BARX2 may be an independent prognostic biomarker for patients suffering from hepatocellular carcinoma (HCC). Nevertheless, the regulatory role of BARX2 in HCC is still unclear and needs to be unveiled. In this study, the expressions of BARX2 and N-acetylgalactosaminyltransferase 4 (GALNT4) were evaluated by quantitative real-time PCR (qRT-PCR) as well as western blot. Besides, the abilities of cells to proliferate, migrate, invade, and angiogenesis were assessed with CCK-8, colony formation, wound-healing, Transwell, and tube formation assays, separately. Cell apoptosis was determined by flow cytometry analysis. The binding relationship between BARX2 and GALNT4 was predicted by JASPAR website and verified using Chromatin immunoprecipitation (ChIP) and luciferase report assay. It was discovered that BARX2 was reduced in HCC cell lines, while its overexpression greatly repressed cell proliferation, migration, invasion, and angiogenesis and promoted cell apoptosis in HuH7 and MHCC97-H cells. BARX2 could bind to GALNT4 promoter and positively regulate GALNT4 expression. In addition, GALNT4 deficiency partly abolished the inhibitory effects of BARX2 on the progression of HCC. In summary, this study highlights that BARX2 may hold promise for serving as a potential therapeutic target, facilitating the development of a novel therapeutic strategy against HCC.

Restoring BARX2 in OSCC reverses partial EMT and suppresses metastasis through miR-186-5p/miR-378a-3p-dependent SERPINE2 inhibition

Tumor cells undergoing partial epithelial-mesenchymal transition (pEMT) are pivotal in local invasion and lymphatic metastasis of oral squamous cell carcinoma (OSCC), yet the mechanisms behind pEMT reversal remain poorly understood. In this study, the loss of BARX2 expression was revealed during the process of oral epithelial carcinogenesis and identified to activate the pEMT program, facilitate metastasis, and be associated with poor prognosis. Restoring BARX2 expression in OSCC cell lines effectively reversed tumor pEMT, evident in E/N-Cadherin switching, reduced cell invasion, proliferation, and stemness, and inhibited murine lung metastasis. BARX2 re-expression negatively correlated with several pEMT markers, notably SERPINE2, which was enriched in the invasive OSCC front, enhancing stemness and promoting metastasis, particularly in cervical lymph nodes. Furthermore, rescuing SERPINE2 impaired the inhibitory effect of BARX2 on the pEMT programs and reconstructed ECM through re-expression of MMP1. Mechanistically, we identified that BARX2 inhibited SERPINE2 through activating miR-186-5p and miR-378a-3p. These miRNAs, upregulated by BARX2, post-transcriptionally degraded SERPINE2 mRNA via targeting specific sequences. Blocking miR-186-5p and miR-378a-3p effectively abolished the negative regulatory effect of BARX2 on SERPINE2. Overall, our findings highlight BARX2 as a partial EMT-reverser in OSCC, providing fresh therapeutic prospects for restoring BARX2 signaling to inhibit invasion and metastasis.

Pancancer analysis of oncogenic BARX2 identifying its prognostic value and immunological function in liver hepatocellular carcinoma

The transcription factor BarH-like homeobox 2 (BARX2), a member of the Bar-like homeobox gene family, is involved in cell proliferation, differentiation, immune responses and tumorigenesis. However, the potential role of BARX2 in the development of liver hepatocellular carcinoma (LIHC) remains unclear. Therefore, we aimed to study the biological role of BARX2 in hepatocellular carcinoma. Through the UALCAN, GTEx PORTAL, TIMER 2.0, LinkedOmics, SMART, MethSurv, Metascape, GSEA and STRING public databases, the BARX2 mRNA level, prognostic value, coexpressed genes, associated differentially expressed genes, DNA methylation and functional enrichment of LIHC patients were studied. The relationships between BARX2 expression and various clinical or genetic parameters of LIHC patients were determined using data from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and BEAT LIHC databases. In addition, the biological function of BARX2 in LIHC was studied in vitro. Through large-scale data mining, our study showed that BARX2 was differentially expressed between different normal and tumour tissues.BARX2 expression in LIHC tissues was significantly lower than that in corresponding controls, especially in patients with T2-4 stage disease. In patients with LIHC, overexpression of BARX2 was an independent poor prognostic factor associated with poor cytogenetic risk and gene mutations. Genomic hypermethylation of the BARX2 gene was associated with upregulated BARX2 expression and poor overall survival (OS) in LIHC. Functional enrichment analysis showed that BARX2 had an immunomodulatory role and was involved in the inflammatory response in LIHC occurrence. In conclusion, the oncogene BARX2 may serve as a new biomarker and prognostic factor for patients with LIHC. The immunomodulatory function of BARX2 deserves further validation in LIHC.

BARX2 expression is downregulated by CpG island hypermethylation and is associated with suppressed cell proliferation and invasion of gastric cancer cells

BarH-like homeobox 2 (BARX2), a homeobox gene, is associated with several types of cancers. The present study aimed to determine whether DNA methylation downregulates BARX2 expression and whether BARX2 is associated with suppression of gastric carcinogenesis. BARX2 protein expression in normal and cancerous gastric tissues and various gastric cancer (GC) cell lines was detected using immunohistochemical and western blot assays. BARX2 mRNA levels were detected using both reverse transcription-polymerase chain reaction (RT-PCR) and quantitative PCR (qPCR). Promoter hypermethylation in GC cells was detected using methylation-specific PCR or bisulfite DNA sequencing PCR. Effects of BARX2 expression on GC cell proliferation, clonal formation, and migration were evaluated after lentivirus-BARX2 transfection. The effect of stable BARX2 transfection on tumor formation was assessed in a nude xenograft mouse model. BARX2 was strongly expressed in the normal gastric mucosa, but weakly or not expressed in GC tissues and most GC cell lines. BARX2 expression was negatively correlated with DNMT (a marker for DNA methylation) expression in the gastric tissues. The BARX2 promoter fragment was hypermethylated in the GC cell lines. Overexpression of BARX2 significantly inhibited GC cell proliferation, clonal formation, and migration. Stable BARX2 transfection inhibited tumor formation in xenograft mice, which was correlated with decreased expression of E-cadherin, proliferation markers, and matrix metalloproteinases. In conclusion, BARX2 expression is aberrantly reduced in GC, which is associated with increased DNA methylation of its promoter. BARX2 inhibits GC cell proliferation, migration, and tumor formation, suggesting that BARX2 acts as a tumor suppressor in gastric carcinogenesis.

DAB2 suppresses gastric cancer migration by regulating the Wnt/β-catenin and Hippo-YAP signaling pathways

BACKGROUND

Disabled-2 (DAB2), a potential tumor suppressor, plays an in important role in cancer development and cellular differentiation. Its lower expression levels have founded in many cancers. In addition, DAB2 is involved in multiple signaling pathways, including TGF-β and Wnt signal pathways. Gastric cancer (GC) is a common gastrointestinal malignant tumor. Nonetheless, the role of DAB2 in GC remains unclear.

METHODS

Thirty-seven clinical specimens of GC tissues and adjacent non-tumor tissues were examined by immunohistochemistry. Proteins were extracted from two of them to perform Western blot analysis. Then, CMV-MCS-3FLAG-SV40-DAB2 and si-DAB2 were transfected into MGC and SGC cell line, respectively. The migration of GC cells was evaluated by transwell migration assay. And, the expression of migration related proteins was detected by Western blot and immunofluorescence (IF).

RESULTS

Eighty-six percent (32/37) of patients DAB2 staining was reduced in GC tissues compared to adjacent normal tissues. Further studies showed that in six human GC cell lines, the level of DAB2 expression was lower than normal gastric epithelial cells, and that DAB2 was closely related to cell migration in vitro. In DAB2 silenced cells, the Wnt/β-catenin signaling was increased and the Hippo-YAP pathway was affected. In addition, lower DAB2 level led to nuclear translocation of β-catenin and Yap.

CONCLUSIONS

The lower expression of DAB2 regulates cell migration in GC via interfering with the Wnt and Hippo signaling pathway. Our findings suggested that DAB2 played an important role in the migration of GC.

Analysis of Copy-Number Variations and Feline Mammary Carcinoma Survival

Feline mammary carcinomas (FMCs) are highly malignant. As the disease-free survival (DFS) and overall survival (OS) are short, prognostication is crucial. Copy-number variations (CNVs) analysis by next-generation sequencing serves to identify critical cancer-related genomic regions. Thirty-three female cats with FMCs were followed during two years after surgery. Tumours represented tubulopapillary and solid carcinomas encompassing six molecular subtypes. Regardless of the histopathological diagnosis, molecular subtypes showed important differences in survival. Luminal A tumours exhibited the highest DFS (p = 0.002) and cancer-specific OS (p = 0.001), and the lowest amount of CNVs (p = 0.0001). In contrast, basal-like triple-negative FMCs had the worst outcome (DFS, p < 0.0001; and OS, p < 0.00001) and were the most aberrant (p = 0.05). In the multivariate analysis, copy-number losses (CNLs) in chromosome B1 (1-23 Mb) harbouring several tumour-repressors (e.g. CSMD1, MTUS1, MSR1, DBC2, and TUSC3) negatively influenced DFS. Whereas, copy-number gains (CNGs) in B4 (1-29 Mb) and F2 (64-82.3 Mb) comprising epithelial to mesenchymal transition genes and metastasis-promoting transcription factors (e.g. GATA3, VIM, ZEB1, and MYC) negatively influenced DFS and cancer-specific OS. These data evidence an association between specific CNVs in chromosomes B1, B4 and F2, and poor prognosis in FMCs.

Elevated expression of AGGF1 predicts poor prognosis and promotes the metastasis of colorectal cancer

Background

Angiogenic factor with G-patch and FHA domains 1 (AGGF1) can promote angiogenesis and increasing evidence has highlighted the important roles of AGGF1 in tumorigenesis. However, the differential expression as well as the biological functions of AGGF1 in colorectal cancer (CRC) remain to be established. The purpose of the present study is therefore to identify the effect of AGGF1 on prognosis and metastasis in CRC patients.

Methods

The expression level of AGGF1 in CRC was examined by qPCR, western blot and immunohistochemistry in a tissue microarray containing 236 CRC specimens and paired normal mucosae. And the effect of AGGF1 on CRC cell malignance was investigated in our established stable AGGF1 upregulated and knockdown CRC cell lines.

Results

The expression level of AGGF1 in CRC tissue was not significantly different to that in adjacent normal mucosa at the mRNA level. However, at the protein level, AGGF1 expression in CRC tissues was significantly higher than in paired normal mucosa, which showed a clear association with TNM stage, AJCC stage, vascular invasion, and differentiation. Further, we revealed an apparent correlation between AGGF1 expression and poorer disease-free survival and overall survival of CRC patients. In addition, we discovered that AGGF1 significantly promoted CRC cell wound healing, migration, and invasion in vitro and distant metastasis in vivo.

Conclusions

Our study demonstrates the aberrant overexpression of AGGF1 in CRC and provides a basis on which to explore the application of AGGF1 as a potential therapeutic target for CRC patients, especially for CRC patients with distant metastasis.

miR-942 promotes tumor migration, invasion, and angiogenesis by regulating EMT via BARX2 in non-small-cell lung cancer

Epithelial-mesenchymal transition (EMT) has an important function in cancer. Recently, microRNAs have been reported to be involved in EMT by regulating target genes. miR-942 is considered a novel oncogene in esophageal squamous cell carcinoma. However, its role in non-small-cell lung cancer (NSCLC) has not been investigated. In this study, the expression of miR-942 in NSCLC patients tumor and paired adjacent tissues were assessed by quantitative real-time polymerase chain reaction and in situ hybridization. Transwell, wound healing, tube formation, and tail vein xenograft assays were conducted to assess miR-942's function in NSCLC. Potential miR-942 targets were confirmed using dual-luciferase reporter assays, immunohistochemistry, immunoblot, and rescue experiments. The results showed miR-942 is relatively highly expressed in human NSCLC tissues and cells. In vitro assays demonstrated that overexpression of miR-942 promoted cell migration, invasion, and angiogenesis. Tail vein xenograft assays suggested that miR-942 contributed to NSCLC metastasis in vivo. Three bioinformatics software was searched, and BARX2 was predicted as a downstream target of miR-942. Direct interaction between them was validated by dual-luciferase assays. Rescue experiments further confirmed that BARX2 overexpression could reverse functional changes caused by miR-942. Moreover, miR-942 increased EMT-associated proteins N-cadherin and vimentin by inhibiting BARX2, while E-cadherin expression is reduced. In summary, this study reveals that miR-942 induces EMT-related metastasis by directly targeting BARX2, which may provide a potential therapeutic strategy for NSCLC.

Review of recent efforts to discover biomarkers for early detection, monitoring, prognosis, and prediction of treatment responses of patients with gastric cancer

Gastric cancer (GC) is the leading cause of cancer-related death worldwide. Despite recent advances in diagnosis and therapy, the prognosis of patients with GC is poor. Many patients have inoperable disease upon diagnosis or experience recurrent disease after curative gastrectomy. Unfortunately, tumor markers for GC, such as serum carcinoembryonic antigen and carbohydrate antigen 19-9, lack sufficient sensitivity and specificity. Therefore, effective biomarkers are required to detect early GC and to predict tumor recurrence and chemosensitivity. Areas covered: Here we aimed to review recent developments in techniques that improve the detection of aberrant expression of GC-associated molecules, including protein coding genes, microRNAs, long noncoding RNAs, and methylated promoter DNAs. Expert commentary: Detection of genetic and epigenetic alterations in gastric tissue or in the circulation will likely improve the diagnosis and management of GC to achieve significantly improved outcomes.

Elevated FOXO6 expression correlates with progression and prognosis in gastric cancer

The FOXO6 correlated with tumor progression in a wide range of carcinomas, yet little is known in gastric cancer. The expression of FOXO6 and matrix metallopeptidase 9 (MMP-9) was assessed by immunohistochemistry in 192 gastric carcinoma specimens. The correlation between FOXO6 expression with MMP-9, clinicopathological/prognostic value in gastric cancer was examined. FOXO6 overexpression was significantly associated with depth of invasion, lymph node metastasis and stage of disease. In univariate and multivariate analyses, FOXO6 was an independent prognostic factor for both overall survival (OS) and recurrence-free survival (RFS). Moreover, FOXO6 over-expression was correlated with poor prognosis in patients subgroups stratified by tumor size, depth of invasion and lymph node metastasis. FOXO6 expression was increased in both prominent serosal invasion group and lymph node metastasis group. In addition, FOXO6 expression was positively correlated with MMP-9 among 192 gastric cancer tissues. Patients with FOXO6 over-expression had poor OS and shorter RFS in low and high invasiveness groups. Furthermore, stratified analysis showed that the TNM stage I patients with high FOXO6 expression had poor prognosis than those with low FOXO6 expression. In conclusion, FOXO6 overexpression promotes tumor aggressiveness and prognosis, and could be a promising target for prognostic prediction in gastric cancer patients.

PCDHGA9 acts as a tumor suppressor to induce tumor cell apoptosis and autophagy and inhibit the EMT process in human gastric cancer

The results of a cDNA  array revealed that protocadherin gamma subfamily A, 9 (PCDHGA9) was significantly decreased in SGC-7901 gastric cancer (GC) cells compared with GES-1 normal gastric cells and was strongly associated with the Wnt/β-catenin and transforming growth factor-β (TGF-β)/Smad2/3 signaling pathway. As a member of the cadherin family, PCDHGA9 functions in both cell-cell adhesion and nuclear signaling. However, its role in tumorigenicity or metastasis has not been reported. In the present study, we found that PCDHGA9 was decreased in GC tissues compared with corresponding normal mucosae and its expression was correlated with the GC TNM stage, the UICC stage, differentiation, relapse, and metastasis (p < 0.01). Multivariate Cox analysis revealed that PCDHGA9 was an independent prognostic indicator for overall survival (OS) and disease-free survival (DFS) (p < 0.01). The effects of PCDHGA9 on GC tumor growth and metastasis were examined both in vivo and in vitro. PCDHGA9 knockdown promoted GC cell proliferation, migration, and invasion, whereas PCDHGA9 overexpression inhibited GC tumor growth and metastasis but induced apoptosis, autophagy, and G1 cell cycle arrest. Furthermore, PCDHGA9 suppressed epithelial-mesenchymal transition (EMT) induced by TGF-β, decreased the phosphorylation of Smad2/3, and inhibited the nuclear translocation of pSmad2/3. Our results suggest that PCDHGA9 might interact with β-catenin to prevent β-catenin from dissociating in the cytoplasm and translocating to the nucleus. Moreover, PCDHGA9 overexpression restrained cell proliferation and reduced the nuclear β-catenin, an indicator of Wnt/β-catenin pathway activation, suggesting that PCDHGA9 negatively regulates Wnt signaling. Together, these data indicate that PCDHGA9 acts as a tumor suppressor with anti-proliferative activity and anti-invasive ability, and the reduction of PCDHGA9 could serve as an independent prognostic biomarker in GC.

Downregulation of BarH-like homeobox 2 promotes cell proliferation, migration and aerobic glycolysis through Wnt/β-catenin signaling, and predicts a poor prognosis in non-small cell lung carcinoma

Background

Human BarH‐like homeobox 2 (Barx2), a homeodomain factor of the Bar family, plays a critical role in cell adhesion and cytoskeleton remodeling, and has been reported in an increasing array of tumor types except non‐small cell lung carcinoma (NSCLC). The purpose of the current study was to characterize the expression of Barx2 and assess the clinical significance of Barx2 in NSCLC.

Methods

Quantitative real‐time polymerase chain reaction, immunohistochemistry and western blot analysis were used to examine mRNA and protein expression, respectively. The relationships between Barx2 expression and clinicopathological variables were analyzed. Cell Counting Kit‐8 and plate colony formation assay were used to detect cell proliferation. Transwell assay was used to examine cell migration ability. Glucose uptake, lactate, adenosine triphosphate, and lactate dehydrogenase assays were used to detect aerobic glycolysis.

Results

Barx2 is downregulated in NSCLC tissues compared with para‐carcinoma. Furthermore, Barx2 expression shows a negative correlation with advanced TNM stage and a high level of Ki‐67. Survival analysis reveals that Barx2 level is an independent prognostic factor for NSCLC patients. The Barx2 (low) Ki‐67 (high) group had the worst prognosis. Furthermore, the data indicate that downregulation of Barx2 expression promotes cell proliferation, migration, and aerobic glycolysis, including increased lactate dehydrogenase activity, glucose utilization, lactate production, and decreased intracellular adenosine triphospahte level. Furthermore, Barx2 acts as a negative regulator of the canonical Wnt/β‐catenin pathway. Reactivation of Wnt/β‐catenin pathway by LiCl can reverse the inhibiting effect of Barx2.

Conclusions

These findings reveal that Barx2 serving as a tumor suppressor gene could decrease cell proliferation, migration, and aerobic glycolysis through inhibiting the Wnt/β‐catenin signaling pathway, and predicts a good prognosis in NSCLC.

Loss of Barx1 promotes hepatocellular carcinoma metastasis through up-regulating MGAT5 and MMP9 expression and indicates poor prognosis

Metastasis is the major dominant reason for poor prognosis of hepatocellular carcinoma (HCC) after surgical treatment. However, the molecular mechanism of metastasis has not been well characterzied. Here, we report a novel function of Barx homeobox1 (Barx1) in inhibiting HCC invasion and metastasis. Barx1 expression is significantly decreased in human HCC tissues than in adjacent non-tumorous tissues and normal liver tissues. Low Barx1 expression is correlated with higher tumor-nodule-metastasis stage and indicates poor prognosis. Down-regulation of Barx1 promotes HCC migration, invasion and metastasis, whereas up-regulation of Barx1 inhibits HCC migration, invasion and metastasis. Mannosyl (alpha-1,6-)-glycoprotein beta-1,6-N-acetyl-glucosaminyltransferase 5 (MGAT5) and matrix metallopeptidase 9 (MMP9) are direct target genes of Barx1. Knockdown of Barx1 up-regulates MGAT5 and MMP9 expression in HCC cells with low metastatic capability, whereas over-expression of Barx1 suppresses their expression in HCC cells with high metastatic capability. Knockdown of both MGAT5 and MMP9 significantly decreases the invasion and metastasis abilities induced by Barx1 knockdown. Barx1 expression is negatively correlated with MGAT5 and MMP9 expression in human HCC tissues. Patients with low expression of Barx1 and high expression of MGAT5 or MMP9 are associated with poorer prognosis. Thus, loss of Barx1 represents a prognostic biomarker in human HCC patients.