HOXB9 promotes epithelial-to-mesenchymal transition via transforming growth factor-β1 pathway in hepatocellular carcinoma cells

The mechanisms, functions and clinical applications of miR-542-3p in human cancers

MicroRNAs, as a major type of noncoding RNAs, have crucial roles in various functions during development. Available data have shown that miR-542-3p decreased in various types of cancers. MiR-542-3p is engaged in various cancer-related behaviors like glycolysis, metastasis, epithelial-to-mesenchymal transition (EMT), cell cycle, apoptosis, and proliferation via targeting at least 18 genes and some important signaling pathways like Wnt/β-catenin, Extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) and Janus kinase 2 (JAK2) signaling, and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling. Current studies have proposed that the level of miR-542-3p could be modulated by several upstream regulators like transcription factors, long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs). In addition, the level of miR-542-3p or its related lncRNAs/circRNAs are correlated with poor prognosis and clinicopathological features of cancer-affected patients. Here, we have discussed the biogenesis, function, and regulation of miR-542-3p as well as its aberrant expression in various types of neoplastic cells. Moreover, we have discussed the prognostic value of miR-542-3p in cancer. Finally, we have added the underlying molecular mechanism of miR-542-3p in cancer pathogenesis.

HOXB9 a miR-122-5p regulated gene, suppressed the anticancer effects of brassaol by upregulating SCD1 expression in melanoma

Brusatol (Bru), a Chinese medicine Brucea javanica extract, has a variety of antitumour effects. However, its role and underlying mechanism in melanoma have not been fully elucidated. In this study, we found that brusatol inhibited melanoma cell proliferation and migration and promoted cell apoptosis in vitro, in addition to suppressing melanoma cell tumorigenesis in vivo. Further studies on the mechanism revealed that brusatol significantly downregulated the expression of stearoyl-CoA desaturase 1 (SCD1). Increased SCD1 expression could impair the antitumour effects of brusatol on melanoma cells. Subsequently, we found that HOXB9, an important transcription factor, was directly bound to the promoter of SCD1, facilitating its transcription. Overexpression of HOXB9 inhibited brusatol-induced SCD1 reduction and promoted cell survival. Furthermore, our results revealed that miR-122-5p was significantly increased in response to brusatol treatment and led to a decrease in HOXB9 in melanoma. Collectively, our data suggested that the miR-122-5p/HOXB9/SCD1 axis might play an important role in the antitumour effects of brusatol and that brusatol might have potential clinical implications in melanoma therapy.

Comprehensive analysis of a homeobox family gene signature in clear cell renal cell carcinoma with regard to prognosis and immune significance

The homeobox (HOX) family genes have been linked to multiple types of tumors, while their effect on malignant behaviors of clear cell renal cell carcinoma (ccRCC) and clinical significance remains largely unknown. Here, we comprehensively analyzed the expression profiles and prognostic value of HOX genes in ccRCC using datasets from The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases. We developed a prognostic signature comprising eight HOX genes (HOXB1, HOXA7, HOXB5, HOXD8, HOXD9, HOXB9, HOXA9, and HOXA11) for overall survival prediction in ccRCC and it allowed patients to be subdivided into high- and low-risk groups. Kaplan-Meier survival analysis in all the internal and external cohorts revealed significant difference in clinical outcome of patients in different risk groups, indicating the satisfactory predictive power of the signature. Additionally, we constructed a prognostic nomogram by integrating signature-derived risk score and clinical factors such as gender, age, T and M status, which might be helpful for clinical decision-making and designing tailored management schedules. Immunological analysis revealed that the regulatory T cells (Tregs) infiltrated differently between the two subgroups in both TCGA and ICGC cohorts. ssGSEA method showed that the enrichment scores for mast cells were significantly lower in high-risk group compared with the low-risk group, which was consistent in both TCGA and ICGC cohorts. As for the related immune function, the enrichment scores of APC co-inhibition, para-inflammation, and type II IFN response were consistently lower in high-risk group in both cohorts. Of the eight HOX genes, the mRNA and protein levels of HOXD8 were downregulated in ccRCC than that in normal tissues, and decreased expression of HOXD8 was associated with increased tumor grade and stage, and lymph node metastasis. Survival analysis revealed that lower expression of HOXD8 predicted worse overall survival in ccRCC. In conclusion, our HOX gene-based signature was a favorable indicator to predict the prognosis of ccRCC cases and associated with immune cell infiltration. HOXD8 might be a tumor suppressor gene in ccRCC and a potential predictor of tumor progression.

Homeobox B9 Promotes the Progression of Hepatocellular Carcinoma via TGF-β1/Smad and ERK1/2 Signaling Pathways

Objectives

Homeobox B9 (HOXB9), a homeodomain-containing transcription factor, may play a role in hepatocellular carcinoma (HCC) progression. However, the exact mechanisms underlying its action remain unclear. Materials and methods. Immunohistochemistry was used to investigate the expression of HOBX9 and its prognostic values in HCC patients. HCC cells were transfected with pBabe-HOXB9 and shHOXB9 plasmids, and MTT assay, Transwell assays, and xenograft mouse models were employed to determine the effects of HOXB9 on HCC cell proliferation, migration, and invasion in vitro and in vivo. The biological mechanisms involved in the role of HOXB9 were determined with Western blot and RT-qPCR methods.

Results

HOXB9 expression was significantly increased in HCC tissues and cell lines. Patients with higher HOXB9 levels were associated with poor prognosis. Overexpression of HOXB9 in BEL-7405 cells promoted proliferation, migration, and invasion, whereas knockdown of HOXB9 in HepG2 cells significantly reduced cell proliferation, migration, and invasion abilities. Mechanically, a positive correlation was found between HOXB9 expression and transforming growth factor-β1 (TGF-β1) and extracellular signal-regulated kinase (ERK)1/2 pathway in HCC tissues. HOXB9 overexpression stimulated TGF-β1/Smads signaling pathway in BEL-7405 cells. In contrast, HOXB9 knockdown inhibited the TGF-β1/Smads signaling pathway in HepG2 cells. In addition, the treatment with TGF-β1 inhibitor, LY364947, significantly reserved HOXB9 overexpression-induced cell proliferation, migration, and invasion abilities.

Conclusions

These findings validated that HOXB9 promoted proliferation, migration, and invasion in HCC cells by stimulating the TGF-β1/Smads and ERK1/2 signaling pathway. HOXB9 could be a promising prognostic biomarker and a potential therapeutic target in HCC.

The AMPK-HOXB9-KRAS axis regulates lung adenocarcinoma growth in response to cellular energy alterations

HOXB9 is an important transcription factor associated with unfavorable outcomes in patients with lung adenocarcinoma (LUAD). However, its degradation mechanism remains unclear. Here, we show that HOXB9 is a substrate of AMP kinase alpha (AMPKα). AMPK mediates HOXB9 T133 phosphorylation and downregulates the level of HOXB9 in mice and LUAD cells. Mechanistically, phosphorylated HOXB9 promoted E3 ligase Praja2-mediated HOXB9 degradation. Blocking HOXB9 phosphorylation by depleting AMPKα1/2 or employing the HOXB9 T133A mutant promoted tumor cell growth in cell culture and mouse xenografts via upregulation of HOXB9 and KRAS that is herein identified as a target of HOXB9. Clinically, AMPK activation levels in LUAD samples were positively correlated with pHOXB9 levels; higher pHOXB9 levels were associated with better survival of patients with LUAD. We thus present a HOXB9 degradation mechanism and demonstrate an AMPK-HOXB9-KRAS axis linking glucose-level-regulated AMPK activation to HOXB9 stability and KRAS gene expression, ultimately controlling LUAD progression.

Expression and Prognostic Role of CXCL1 Gene in Colorectal Adenocarcinoma

In this manuscript, we have extensively examined expression and prognosis of CXCL1 gene in colorectal adenocarcinoma (COAD) using different cases of colorectal adenocarcinoma and tissues. To verify this, protein and mRNA expressions of cxcl1 were identified through RT-PCR and immunohistochemistry in 30 cases of colorectal adenocarcinoma and adjacent tissues, which were surgically resected from January to July 2021 in our hospital, and relationship between CXCL1 mRNA and clinicopathological features and protein expression was analyzed. CXCL 1 mRNA in COAD carcinoma's expression was considerably higher than in the adjacent normal intestine. At the same time, CXCL 1 diagnostic receiver operating characteristic (ROC) curve had preferably higher value of the diagnostic for area under curve (AUC) = 0.912, 95%, COAD (P < 0.001, CI = 0.825–0.969). We have observed that CXCL1 gene was closely linked with preoperative CEA level (P=0.007) and gross tumor typing (P=0.039). Finally, we have concluded that that CXCL1 can be a possible biomarker for stress prognosis and diagnosis.

Establishing a Prognostic Signature Based on Epithelial-Mesenchymal Transition-Related Genes for Endometrial Cancer Patients

Backgrounds

Epithelial-mesenchymal transition (EMT) is a sequential process where tumor cells develop from the epithelial state to the mesenchymal state. EMT contributes to various tumor functions including initiation, propagating potential, and resistance to therapy, thus affecting the survival time of patients. The aim of this research is to set up an EMT-related prognostic signature for endometrial cancer (EC).

Methods

EMT-related gene (ERG) expression and clinical data were acquired from The Cancer Genome Atlas (TCGA). The entire set was randomly divided into two sets, one for contributing the risk model (risk score) and the other for validating. Univariate and multivariate Cox proportional hazards regression analyses were applied to the training set to select the prognostic ERGs. The expression of 10 ERGs was confirmed by qRT-PCR in clinical samples. Then, we developed a nomogram predicting 1-/3-/5-year survival possibility combining the risk score and clinical factors. The entire set was stratified into the high- and low-risk groups, which was used to analyze the immune infiltrating, tumorigenesis pathways, and response to drugs.

Results

A total of 220 genes were screened out from 1,316 ERGs for their differential expression in tumor versus normal. Next, 10 genes were found to be associated with overall survival (OS) in EC, and the expression was validated by qRT-PCR using clinical samples, so we constructed a 10-ERG-based risk score to distinguish high-/low-risk patients and a nomogram to predict survival rate. The calibration plots proved the predictive value of our model. Gene Set Enrichment Analysis (GSEA) discovered that in the low-risk group, immune-related pathways were enriched; in the high-risk group, tumorigenesis pathways were enriched. The low-risk group showed more immune activities, higher tumor mutational burden (TMB), and higher CTAL4/PD1 expression, which was in line with a better response to immune checkpoint inhibitors. Nevertheless, response to chemotherapeutic drugs turned out better in the high-risk group. The high-risk group had higher N ⁶-methyladenosine (m⁶A) RNA expression, microsatellite instability level, and stemness indices.

Conclusion

We constructed the ERG-related signature model to predict the prognosis of EC patients. What is more, it might offer a reference for predicting individualized response to immune checkpoint inhibitors and chemotherapeutic drugs.

Molecular implications of HOX genes targeting multiple signaling pathways in cancer

Homeobox (HOX) genes encode highly conserved homeotic transcription factors that play a crucial role in organogenesis and tissue homeostasis. Their deregulation impacts the function of several regulatory molecules contributing to tumor initiation and progression. A functional bridge exists between altered gene expression of individual HOX genes and tumorigenesis. This review focuses on how deregulation in the HOX-associated signaling pathways contributes to the metastatic progression in cancer. We discuss their functional significance, clinical implications and ascertain their role as a diagnostic and prognostic biomarker in the various cancer types. Besides, the mechanism of understanding the theoretical underpinning that affects HOX-mediated therapy resistance in cancers has been outlined. The knowledge gained shall pave the way for newer insights into the treatment of cancer.

WT1 regulates HOXB9 gene expression in a bidirectional way

The homeoboxB9 (HOXB9) gene is necessary for specification of the anterior-posterior body axis during embryonic development and expressed in various types of cancer. Here we show that the Wilms tumor transcription factor WT1 regulates the HOXB9 gene in a bidirectional manner. Silencing of WT1 activates HOXB9 in Wt1 expressing renal cell adenocarcinoma-derived 786-0 cells, mesonephric M15 cells and ex vivo cultured murine embryonic kidneys. In contrast, HOXB9 expression in U2OS osteosarcoma and human embryonic kidney (HEK) 293 cells, which lack endogenous WT1, is enhanced by overexpression of WT1. Consistently, Hoxb9 promoter activity is stimulated by WT1 in transiently transfected U2OS and HEK293 cells, but inhibited in M15 cells with CRISPR/Cas9-mediated Wt1 deletion. Electrophoretic mobility shift assay and chromatin immunoprecipitation demonstrate binding of WT1 to the HOXB9 promoter in WT1-overexpressing U2OS cells and M15 cells. BASP1, a transcriptional co-repressor of WT1, is associated with the HOXB9 promoter in the chromatin of these cell lines. Co-transfection of U2OS and HEK293 cells with BASP1 plus WT1 prevents the stimulatory effect of WT1 on the HOXB9 promoter. Our findings identify HOXB9 as a novel downstream target gene of WT1. Depending on the endogenous expression of WT1, forced changes in WT1 can either stimulate or repress HOXB9, and the inhibitory effect of WT1 on transcription of HOXB9 involves BASP1. Consistent with inhibition of Hoxb9 expression by WT1, both transcripts are distributed in an almost non-overlapping pattern in embryonic mouse kidneys. Regulation of HOXB9 expression by WT1 might become relevant during kidney development and cancer progression.

HOXB5 promotes proliferation, migration, and invasion of pancreatic cancer cell through the activation of the GSK3β/β-catenin pathway

Many homeobox (HOX) genes have been shown to be related to cancer progression. HOXB5, a member of the HOX genes, is overexpressed in retinoblastoma cancer and positively regulates the breast cancer cell proliferation as well as invasion. However, the role and underlying mechanism of HOXB5 in pancreatic cancer cells are still unclear. HOXB5 expression was measured in four pancreatic cancer cell lines, including PANC-1, ASPC-1, MIA-PaCa-2, and CFPAC-1. PANC-1 and ASPC-1 cells were selected for cell transfection experiments. Cell proliferation, migration, and invasion were measured by Cell Counting Kit-8 (CCK-8) assay, wound healing assay, and transwell assay. Expressions of epithelial-to-mesenchymal transition (EMT) markers were determined by western blotting. Immunofluorescence staining and cellular morphology were used to confirm the effect of HOXB5 dysregulation on pancreatic cancer cells. We found that HOXB5 was markedly expressed in pancreatic cancer cell lines. HOXB5 overexpression contributed to proliferation, migration, and invasion in ASPC-1 cells, whereas HOXB5 knockdown decreased proliferation, migration, and invasion of PANC-1 cells. Western blotting confirmed that overexpression of HOXB5 promoted the EMT process. Conversely, knockdown of HOXB5 alleviated EMT. Furthermore, knockdown of HOXB5 suppressed proliferation, migration, and invasion of pancreatic cancer cells via the Glycogen synthase kinase 3β (GSK3β)/β-catenin pathway. Our study demonstrates that HOXB5 is a tumor promoter in pancreatic cancer, and the GSK3β/β-catenin pathway is important in HOXB5-induced proliferation, migration, and invasion in pancreatic cancer cells.

HOXB9 enhances the ability of lung cancer cells to penetrate the blood-brain barrier

Even after multimodal therapy, the prognosis is dismal for patients with brain metastases from non-small cell lung cancer (NSCLC). Although the blood-brain barrier (BBB) limits tumor cell penetration into the brain parenchyma, some nevertheless colonize brain tissue through mechanisms that are not fully clear. Here we show that homeobox B9 (HOXB9), which is commonly overexpressed in NSCLC, promotes epithelial-to-mesenchymal transition (EMT) and tumor migration and invasion. Animal experiments showed that HOXB9 expression correlates positively with the brain metastatic potential of human NSCLC cells, while brain metastatic cells derived through in vivo selection showed greater HOXB9 expression than their cells of origin. Comparable results were obtained after immunohistochemical analysis of clinical primary NSCLC and matched brain metastasis samples obtained after surgery. Using an in vitro BBB model, knockdown and overexpression experiments showed that HOXB9-dependent expression of MMP9 in NSCLC cells leads to reduced expression of junctional proteins in cultured human vascular endothelial cells and enhanced transmigration of tumor cells. These data indicate that HOXB9 enables NSCLC cells to break away from the primary tumor by inducing EMT, and promotes brain metastasis by driving MMP9 production and degradation of intercellular adhesion proteins in endothelial cells comprising the BBB.

HOX Genes Family and Cancer: A Novel Role for Homeobox B9 in the Resistance to Anti-Angiogenic Therapies

Simple Summary

The inhibition of angiogenesis, relying on the use of drugs targeting the VEGF signaling pathway, has become one of the main strategies for cancer treatment. However, the intrinsic and acquired resistance to this type of therapy limit its efficacy. Thus, the identification of novel therapeutic targets is urgently needed. The resistance to anti-angiogenic treatment often occurs through the activation of alternative VEGF independent signaling pathways and recruitment of bone marrow-derived pro-angiogenic cells in the tumor microenvironment. HOX genes are key regulators of embryonic development, also involved in angiogenesis and in cancer progression. HOXB9 upregulation occurs in many types of cancer and it has been identified as a critical transcription factor involved in tumour resistance to anti-angiogenic drugs. Indeed, HOXB9 modulates the expression of alternative pro-angiogenic secreted factors in the tumour microenvironment leading tumor escape from the anti-angiogenic treatments. Hence, HOXB9 could serves as a novel therapeutic target to overcome the resistance to anti-angiogenic therapies.

Abstract

Angiogenesis is one of the hallmarks of cancer, and the inhibition of pro-angiogenic factors and or their receptors has become a primary strategy for cancer therapy. However, despite promising results in preclinical studies, the majority of patients either do not respond to these treatments or, after an initial period of response, they develop resistance to anti-angiogenic agents. Thus, the identification of a novel therapeutic target is urgently needed. Multiple mechanisms of resistance to anti-angiogenic therapy have been identified, including the upregulation of alternative angiogenic pathways and the recruitment of pro-angiogenic myeloid cells in the tumor microenvironment. Homeobox containing (HOX) genes are master regulators of embryonic development playing a pivotal role during both embryonic vasculogenesis and pathological angiogenesis in adults. The importance of HOX genes during cancer progression has been reported in many studies. In this review we will give a brief description of the HOX genes and their involvement in angiogenesis and cancer, with particular emphasis on HOXB9 as a possible novel target for anti-angiogenic therapy. HOXB9 upregulation has been reported in many types of cancers and it has been identified as a critical transcription factor involved in resistance to anti-angiogenic drugs.

Five genes as a novel signature for predicting the prognosis of patients with laryngeal cancer

In this study, we purpose to investigate a novel five-gene signature for predicting the prognosis of patients with laryngeal cancer. The laryngeal cancer datasets were obtained from The Cancer Genome Atlas (TCGA). Both univariate and multivariate Cox regression analysis was applied to screening for prognostic differential expressed genes (DEGs), and a novel gene signature was obtained. The performance of this Cox regression model was tested by receiver operating characteristic (ROC) curves and area under the curve (AUC). Further survival analysis for each of the five genes was carried out through the Kaplan-Meier curve and Log-rank test. Totally, 622 DEGs were screened from the TCGA datasets in this study. We construct a five-gene signature through Cox survival analysis. Patients were divided into low- and high-risk groups depending on the median risk score, and a significant difference of the 5-year overall survival was found between these two groups (P < .05). ROC curves verified that this five-gene signature had good performance to predict the prognosis of laryngeal cancer (AUC = 0.862, P < .05). In conclusion, the five-gene signature consist of EMP1, HOXB9, DPY19L2P1, MMP1, and KLHDC7B might be applied as an independent prognosis predictor of laryngeal cancer.

Identification of a Modified HOXB9 mRNA in Breast Cancer

First identified as a developmental gene, HOXB9 is also known to be involved in tumor biological processes, and its aberrant expression correlates with poor prognosis of various cancers. In this study, we isolated a homeodomain-less, novel HOXB9 variant (HOXB9v) from human breast cancer cell line-derived mRNA. We confirmed that the novel variant was produced from variationless HOXB9 genomic DNA. RT-PCR of mRNA isolated from clinical samples and reanalysis of publicly available RNA-seq data proved that the new transcript is frequently expressed in human breast cancer. Exogenous HOXB9v expression significantly enhanced the proliferation of breast cancer cells, and gene ontology analysis indicated that apoptotic signaling was suppressed in these cells. Considering that HOXB9v lacks key domains of homeobox proteins, its behavior could be completely different from that of the previously described variationless HOXB9. Because none of the previous studies on HOXB9 have considered the presence of HOXB9v, further research analyzing the two transcripts individually is warranted to re-evaluate the true role of HOXB9 in cancer.

HOX family transcription factors: Related signaling pathways and post-translational modifications in cancer

HOX family transcription factors belong to a highly conserved subgroup of the homeobox superfamily that determines cellular fates in embryonic morphogenesis and the maintenance of adult tissue architecture. HOX family transcription factors play key roles in numerous cellular processes including cell growth, differentiation, apoptosis, motility, and angiogenesis. As tumor promoters or suppressors HOX family members have been reported to be closely related with a variety of cancers. They closely regulate tumor initiation and growth, invasion and metastasis, angiogenesis, anti-cancer drug resistance and stem cell origin. Here, we firstly described the pivotal roles of HOX transcription factors in tumorigenesis. Then, we summarized the main signaling pathways regulated by HOX transcription factors, including Wnt/β-catenin, transforming growth factor β, mitogen-activated protein kinase, phosphoinositide 3-kinase/Akt, and nuclear factor-κB signalings. Finally, we outlined the important post-translational modifications of HOX transcription factors and their regulation in cancers. Future research directions on the HOX transcription factors are also discussed.

Homeobox Genes and Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common type of cancer, and is the third leading cause of cancer-related deaths each year. It involves a multi-step progression and is strongly associated with chronic inflammation induced by the intake of environmental toxins and/or viral infections (i.e., hepatitis B and C viruses). Although several genetic dysregulations are considered to be involved in disease progression, the detailed regulatory mechanisms are not well defined. Homeobox genes that encode transcription factors with homeodomains control cell growth, differentiation, and morphogenesis in embryonic development. Recently, more aberrant expressions of Homeobox genes were found in a wide variety of human cancer, including HCC. In this review, we summarize the currently available evidence related to the role of Homeobox genes in the development of HCC. The objective is to determine the roles of this conserved transcription factor family and its potential use as a therapeutic target in future investigations.

HOXB9 inhibits proliferation in gastric carcinoma cells via suppression of phosphorylated-Akt and NF-κB-dependent Snail expression

BACKGROUND

HOXB9 is a homeobox transcription factor which plays an important role in carcinoma development. This protein has been shown to inhibit cancer cell proliferation. However, the mechanisms that underpin HOXB9-mediated inhibition of cellular proliferation remain to be elucidated.

METHODS

In this study, two gastric cancer cell lines, SGC7901 and MKN45, were transfected with plasmids pLVX-HOXB9 and shHOXB9. These transfections resulted in the over-expression of the HOXB9 gene in the SGC7901/HOXB9 cells and knockdown of the HOXB9 gene in the MKN45/shHOXB9 cells.

RESULTS

Over-expression of the HOXB9 gene in the SGC7901/HOXB9 cells caused an increase in the apoptotic rate and a concomitant reduction in metastatic ability compared with the knocked-down MKN45/shHOXB9 cells. Moreover, a reduction in the expression of the phosphorylated-Akt protein was observed in the SGC7901/HOXB9 cells, while an increase in expression of the same protein was observed in the MKN45/shHOXB9 cells. We also observed that HOXB9 mediated a reduction in both NF-κB and N-cadherin and Snail protein expression. Conversely, HOXB9 caused an increase in the expression of E-cadherin.

CONCLUSIONS

In summary, this study reports that HOXB9 can suppress both phosphorylated-Akt expression and NF-κB activity. The latter phenomenon affects Snail protein expression and the inhibition of gastric carcinoma proliferation.

Downregulation of miR-542-3p promotes cancer metastasis through activating TGF-β/Smad signaling in hepatocellular carcinoma

Introduction

Hepatocellular carcinoma (HCC) accounts for more than 90% of primary liver cancer. Although great progress has been made on HCC molecular mechanism and therapy techniques, the prognosis of HCC patient is poor due to high metastasis and recurrence.

Materials and methods

Expression of miR-542-3p was quantified by quantitative real-time PCR (qRT-PCR). The role of miR-542-3p in HCC metastasis was examined using transwell and 3D-culture assay. qRT-PCR, Western blotting and luciferase reporter assay were used to elucidate the mechanisms of miR-542-3p-mediated cancer metastasis.

Results and Conclusion

In the research, we found that miR-542-3p is decreased in HCC cell lines and tissues, and downregulation of miR-542-3p enhances, while upregulation suppresses HCC cell invasion ability. Further assay demonstrated that miR-542-3p can directly target TGF-β1 3′ untranslated region (3′UTR) to influence TGF-β/Smad signaling pathway, and suppression of miR-542-3p can hyperactivate TGF-β/Smad pathway and further to promote Epithelial-Mesenchyme Transition (EMT) and induce poor prognosis. Lastly, the clinical correlation analysis illustrated that miR-542-3p is negatively related with the activity of TGF-β1. In summary, our results find that miR-542-3p takes an important role on HCC progression and provide more evidence of microRNAs (miRNAs) for cancer therapy.

Overexpression of non‑SMC condensin I complex subunit G serves as a promising prognostic marker and therapeutic target for hepatocellular carcinoma

The non-SMC condensin I complex subunit G (NCAPG) that organizes the coiling topology of individual chromatids, represents an overexpressed antigen in various types of cancer, and also contributes to restructuring chromatin into rod-shaped mitotic chromosomes and ensuring the segregation of sister chromatid during cell division. In this study, we investigated the association between NCAPG expression and the biological behavior of hepatocellular carcinoma (HCC) to further explore the potential of NCAPG as a therapeutic target. The expression of NCAPG was detected in human HCC cell lines and tumor samples. The effects of NCAPG on the cell cycle, apoptosis and metastasis were investigated by various assays. NCAPG was found to be overexpressed in HCC compared with the adjacent normal tissue (P<0.001), and high levels of NCAPG expression were found to significantly correlate with recurrence, the time of recurrence, metastasis, differentiation and TNM stage. Furthermore, an elevated expression of NCAPG was associated with a poor overall survival (P<0.05). In addition, in vitro experiments further confirmed the ex vivo data; i.e., the knockdown of NCAPG expression reduced HCC cell viability, but induced apoptosis and arrested the cells at the S phase of the cell cycle. The knockdown of NCAPG expression also inhibited tumor cell migration and the cell invasive capacity in vitro. At the protein level, the knockdown of NCAPG expression upregulated Bax, cleaved caspase-3 and E-cadherin, but downregulated cyclin A1, CDK2, Bcl-2, N-cadherin and HOXB9 expression, suggesting that the knockdown of NCAPG expression suppressed tumor cell epithelial-mesenchymal transition. On the whole, this study demonstrates that NCAPG plays an important role in the development and progression of HCC, and that it may be a novel therapeutic target for patients with HCC.

Dynamic Pattern of HOXB9 Protein Localization during Oocyte Maturation and Early Embryonic Development in Mammals

Background

We previously showed that the homeodomain transcription factor HOXB9 is expressed in mammalian oocytes and early embryos. However, a systematic and exhaustive study of the localization of the HOXB9 protein, and HOX proteins in general, during mammalian early embryonic development has so far never been performed.

Results

The distribution of HOXB9 proteins in oocytes and the early embryo was characterized by immunofluorescence from the immature oocyte stage to the peri-gastrulation period in both the mouse and the bovine. HOXB9 was detected at all studied stages with a dynamic expression pattern. Its distribution was well conserved between the two species until the blastocyst stage and was mainly nuclear. From that stage on, trophoblastic cells always showed a strong nuclear staining, while the inner cell mass and the derived cell lines showed important dynamic variations both in staining intensity and in intra-cellular localization. Indeed, HOXB9 appeared to be progressively downregulated in epiblast cells and only reappeared after gastrulation had well progressed. The protein was also detected in the primitive endoderm and its derivatives with a distinctive presence in apical vacuoles of mouse visceral endoderm cells.

Conclusions

Together, these results could suggest the existence of unsuspected functions for HOXB9 during early embryonic development in mammals.

Endocrine disrupting chemical, bisphenol-A, induces breast cancer associated gene HOXB9 expression in vitro and in vivo

HOXB9 is a homeobox-containing gene that plays a key role in mammary gland development and is associated with breast and other types of cancer. Here, we demonstrate that HOXB9 expression is transcriptionally regulated by estradiol (E2), in vitro and in vivo. We also demonstrate that the endocrine disrupting chemical bisphenol-A (BPA) induces HOXB9 expression in cultured human breast cancer cells (MCF7) as well as in vivo in the mammary glands of ovariectomized (OVX) rats. Luciferase assay showed that estrogen-response-elements (EREs) in the HOXB9 promoter are required for BPA-induced expression. Estrogen-receptors (ERs) and ER-co-regulators such as MLL-histone methylase (MLL3), histone acetylases, CBP/P300, bind to the HOXB9 promoter EREs in the presence of BPA, modify chromatin (histone methylation and acetylation) and lead to gene activation. In summary, our results demonstrate that BPA exposure, like estradiol, increases HOXB9 expression in breast cells both in vitro and in vivo through a mechanism that involves increased recruitment of transcription and chromatin modification factors.

HOXB13 and ALX4 induce SLUG expression for the promotion of EMT and cell invasion in ovarian cancer cells

Homeoproteins, a family of transcription factors that have conserved homeobox domains, play critical roles in embryonic development in a wide range of species. Accumulating studies have revealed that homeoproteins are aberrantly expressed in multiple tumors and function as either tumor promoters or suppressors. In this study, we show that two homeoproteins, HOXB13 and ALX4, are associated with epithelial to mesenchymal transition (EMT) and invasion of ovarian cancer cells. HOXB13 and ALX4 formed a complex in cells, and exogenous expression of either protein promoted EMT and invasion. Conversely, depletion of either protein suppressed invasion and induced reversion of EMT. SLUG is a C2H2-type zinc-finger transcription factor that promotes EMT in various cell lines. Knockdown of HOXB13 or ALX4 suppressed SLUG expression, and exogenous expression of either protein promoted SLUG expression. Finally, we showed that SLUG expression was essential for the HOXB13- or ALX4-mediated EMT and invasion. Our results show that HOXB13/SLUG and ALX4/SLUG axes are novel pathways that promote EMT and invasion of ovarian cancer cells.

HOXD9 promotes epithelial-mesenchymal transition and cancer metastasis by ZEB1 regulation in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumor that severely threatens human health. The poor prognosis of HCC is mainly attributed to intrahepatic and extrahepatic metastases. HOXD9 proteins belong to a superfamily that regulates the development and control of many cellular processes, including proliferation, apoptosis, cell shape, and cell migration. HOXD9 can also function as an oncogene in several cancer cells. However, its biological function in human HCC requires further investigation. In this study, HOXD9 exhibited high expression in invasive HCC cells. HOXD9 overexpression can significantly enhance HCC cell migration, invasion, and metastasis, whereas silencing HOXD9 inhibits these processes. HOXD9 also promotes the epithelial-mesenchymal transition (EMT) of HCC cells. Microarray analysis suggests that ZEB1 can function as a downstream factor of HOXD9. HOXD9 can interact with the promoter region of ZEB1 and promotes ZEB1 expression. ZEB1 knockdown inhibits HOXD9-induced migration and invasion, as well as EMT in HCC cells. This study helps elucidates the oncogenic functions of HOXD9 in HCC.

Management strategies for hepatocellular carcinoma: old certainties and new realities

Hepatocellular carcinoma (HCC) is a highly prevalent disease ranking among the ten most common cancers worldwide with increasing trend of incidence in most developed countries. The great healthcare costs and economic burden of HCC dictate proper preventive interventions as well as surveillance and screening programs to decrease disease incidence and allow early diagnosis. HCC treatment outcomes are affected by several variables, including liver function, patient's performance status, and tumor stage. In line with the Barcelona Clinic Liver Cancer (BCLC) staging curative treatments, such as surgery or radio-frequency ablation, are indicated in early-stage HCC (BCLC-A), and the noncurative treatments are indicated in intermediate and advanced stages of HCC (BCLC-B, C). Transarterial chemoembolization (TACE) represents the treatment of choice for intermediate-stage HCC with Child-Pugh A cirrhosis, and the long-term survival after liver transplantation is inferior to that of early-stage HCCs. In advanced-stage HCC or when complete necrosis is not achieved or early recurrence after TACE develops, individualized treatments such as systemic treatment or combined radiation therapy are indicated. The increasing knowledge of the genomic landscape of HCC and the development of molecular-targeted therapies is heading toward expanding the armamentarium for HCC management.

The role of HOXB9 and miR-196a in head and neck squamous cell carcinoma

Background

Previous studies have demonstrated that a number of HOX genes, a family of transcription factors with key roles in early development, are up-regulated in head and neck squamous cell carcinoma (HNSCC) and other cancers. The loci of several Homeobox (HOX) genes also contain microRNAs (miRs), including miR-196a.

Methods

Global miR expression and expression of all 39 HOX genes in normal oral keratinocytes (NOKs), oral pre-malignant (OPM) and HNSCC cells was assessed by expression microarray and qPCR and in tissues by immunohistochemistry (IHC) and qPCR of laser microdissected (LCM) tissues. Expression of miR196a and HOXB9 was reduced using anti-miR-196a and siRNA, respectively. Expression microarray profiles of anti-miR196a and pre-miR196a transfected cells were compared to parental cells in order to identify novel targets of miR-196a. Putative miR196a targets were validated by qPCR and were confirmed as binding to the 3’UTR of miR196a by a dual luciferase reporter assay combined with mutational analysis of the miR-196a binding site.

Results

miR-196a and HOXB9 are highly expressed in HNSCC compared to NOKs, a pattern also seen in HNSCC tissues by HOXB9 IHC and qPCR of miR-196a in LCM tissue. Knock-down of miR-196a expression decreased HNSCC cell migration, invasion and adhesion to fibronectin, but had no effect on proliferation. Furthermore, knock-down of HOXB9 expression decreased migration, invasion and proliferation but did not alter adhesion. We identified a novel primary mRNA transcript containing HOXB9 and miR196a-1 as predicted from in-silico analysis. Expression array analysis identified a number of miR196a targets, including MAMDC2 and HOXC8. We confirmed that MAMDC2 is a novel miR-196a target using a dual luciferase reporter assay with the effect abolished on mutation of the binding site.

Conclusions

These results show that miR-196a and HOXB9 are overexpressed, perhaps co-ordinately, as HNSCC develops and exert a pro-tumourigenic phenotype in HNSCC and OPM cells.

Fighting the force: Potential of homeobox genes for tumor microenvironment regulation

Tumor cells exist in a constantly evolving stromal microenvironment composed of vasculature, immune cells and cancer-associated fibroblasts, all residing within a dynamic extracellular matrix. In this review, we examine the biochemical and biophysical interactions between these various stromal cells and their matrix microenvironment. While the stroma can alter tumor progression via multiple mechanisms, we emphasize the role of homeobox genes in detecting and modulating the mechanical changes in the microenvironment during tumor progression.