Silencing of HMGA2 promotes apoptosis and inhibits migration and invasion of prostate cancer cells

MicroRNA-143-5p Suppresses ER-Positive Breast Cancer Development by Targeting Oncogenic HMGA2

BACKGROUND

About 70%-80% of breast cancers (BCs) express estrogen receptors (ER-positive). MicroRNAs (miRNAs) are a group of small endogenous noncoding RNAs that play a critical regulatory role in cancer development and progression, including in BC. MiRNA deficiency promotes the development of BCs. MiR-143-5p is one of the most commonly dysregulated miRNAs in BC but its role as a tumor suppressor remains unclear.

MATERIALS AND METHODS

MiR-143-3p and -5p expression in breast tissue was analyzed using TCGA and StarBase databases. Expression in BC subclasses and survival analyses were conducted. Clinical samples were collected, cell cultures created, and gene expression assays performed following previous studies. Protein expression, luciferase reporter, wound healing, DAPI staining, cell cycle, colony formation, spheroid, CD44 FACS, and proliferation assays were conducted following various protocols.

RESULTS

Here, we find that both miR-143-3p and miR-143-5p levels are considerably lower in BC tissue compared to normal breast tissue and low miR-143 expression predicts poor prognosis in ER+ BC patients. In-depth analyses identified 3 miR-143-5p binding sites in the 3' untranslated region (UTR) of the DNA binding protein High Mobility Group AT-Hook 2 (HMGA2). Luciferase reporter assays using wild-type and mutant HMGA2 3'UTR sequences and Western blot analyses demonstrated that HMGA2 is a direct and bona fide miR-143-5p target in BC cells. In addition, we show that restoration of miR-143-5p expression suppresses metastasis-related features of ER+ BC cells, including reduced tumor cell migration, increased E-cadherin expression, and decreased vimentin and N-cadherin expression. Furthermore, miR-143-5p reduces cell proliferation, cell cycle entry, and stemness, while promoting apoptosis moderately. Finally, patient sample pathway analyses demonstrated that these mechanisms are also active in BC.

CONCLUSIONS

Altogether, our findings shed new light on miR-143-5p's anticancer biological functions in BC progression by directly targeting HMGA2. This suggests that restoration of miR-143-5p could be a promising new therapeutic approach for the treatment of ER+ BC.

Non-coding RNAs and exosomal non-coding RNAs in pituitary adenoma

Pituitary adenoma (PA) is the third most common primary intracranial tumor in terms of overall disease incidence. Although they are benign tumors, they can have a variety of clinical symptoms, but are mostly asymptomatic, which often leads to diagnosis at an advanced stage when surgical intervention is ineffective. Earlier identification of PA could reduce morbidity and allow better clinical management of the affected patients. Non-coding RNAs (ncRNAs) do not generally code for proteins, but can modulate biological processes at the post-transcriptional level through a variety of molecular mechanisms. An increased number of ncRNA expression profiles have been found in PAs. Therefore, understanding the expression patterns of different ncRNAs could be a promising method for developing non-invasive biomarkers. This review summarizes the expression patterns of dysregulated ncRNAs (microRNAs, long non-coding RNAs, and circular RNAs) involved in PA, which could one day serve as innovative biomarkers or therapeutic targets for the treatment of this neoplasia. We also discuss the potential molecular pathways by which the dysregulated ncRNAs could cause PA and affect its progression.

HMGA2 regulation by miRNAs in cancer: affecting cancer hallmarks and therapy response

High mobility group A 2 (HMGA2) is a protein that modulates the structure of chromatin in the nucleus. Importantly, aberrant expression of HMGA2 occurs during carcinogenesis, and this protein is an upstream mediator of cancer hallmarks including evasion of apoptosis, proliferation, invasion, metastasis, and therapy resistance. HMGA2 targets critical signaling pathways such as Wnt/β-catenin and mTOR in cancer cells. Therefore, suppression of HMGA2 function notably decreases cancer progression and improves outcome in patients. As HMGA2 is mainly oncogenic, targeting expression by non-coding RNAs (ncRNAs) is crucial to take into consideration since it affects HMGA2 function. MicroRNAs (miRNAs) belong to ncRNAs and are master regulators of vital cell processes, which affect all aspects of cancer hallmarks. Long ncRNAs (lncRNAs) and circular RNAs (circRNAs), other members of ncRNAs, are upstream mediators of miRNAs. The current review intends to discuss the importance of the miRNA/HMGA2 axis in modulation of various types of cancer, and mentions lncRNAs and circRNAs, which regulate this axis as upstream mediators. Finally, we discuss the effect of miRNAs and HMGA2 interactions on the response of cancer cells to therapy. Regarding the critical role of HMGA2 in regulation of critical signaling pathways in cancer cells, and considering the confirmed interaction between HMGA2 and one of the master regulators of cancer, miRNAs, targeting miRNA/HMGA2 axis in cancer therapy is promising and this could be the subject of future clinical trial experiments.

Identification of Genomic Regions and Candidate Genes Associated with Body Weight and Body Conformation Traits in Karachai Goats

The objective of this study was to identify the SNPs and candidate genes related to body weight and seven body conformation traits at the age of 8 months in the Russian aboriginal Karachai goats (n = 269) by conducting genome-wide association studies (GWAS), using genotypes generated by Goat SNP BeadChip (Illumina Inc., USA). We identified 241 SNPs, which were significantly associated with the studied traits, including 47 genome-wide SNPs (p < 10−5) and 194 suggestive SNPs (p < 10−4), distributed among all goat autosomes except for autosome 23. Fifty-six SNPs were common for two and more traits (1 SNP for six traits, 2 SNPs for five traits, 12 SNPs for four traits, 20 SNPs for three traits, and 21 SNPs for two traits), while 185 SNPs were associated with single traits. Structural annotation within a window of 0.4 Mb (±0.2 Mb from causal SNPs) revealed 238 candidate genes. The largest number of candidate genes was identified at Chr13 (33 candidate genes for the five traits). The genes identified in our study were previously reported to be associated with growth-related traits in different livestock species. The most significant genes for body weight were CRADD, HMGA2, MSRB3, MAX, HACL1 and RAB15, which regulate growth processes, body sizes, fat deposition, and average daily gains. Among them, the HMGA2 gene is a well-known candidate for prenatal and early postnatal development, and the MSRB3 gene is proposed as a candidate gene affecting the growth performance. APOB, PTPRK, BCAR1, AOAH and ASAH1 genes associated with withers height, rump height and body length, are involved in various metabolic processes, including fatty acid metabolism and lipopolysaccharide catabolism. In addition, WDR70, ZBTB24, ADIPOQ, and SORCS3 genes were linked to chest width. KCNG4 was associated with rump height, body length and chest perimeter. The identified candidate genes can be proposed as molecular markers for growth trait selection for genetic improvement in Karachai goats.

MicroRNAs as the critical regulators of cell migration and invasion in thyroid cancer

Thyroid cancer (TC) is one of the most frequent endocrine malignancies that is more common among females. Tumor recurrence is one of the most important clinical manifestations in differentiated TC which is associated with different factors including age, tumor size, and histological features. Various molecular processes such as genetic or epigenetic modifications and non-coding RNAs are also involved in TC progression and metastasis. The epithelial-to-mesenchymal transition (EMT) is an important biological process during tumor invasion and migration that affects the initiation and transformation of early-stage tumors into invasive malignancies. A combination of transcription factors, growth factors, signaling pathways, and epigenetic regulations affect the thyroid cell migration and EMT process. MicroRNAs (miRNAs) are important molecular factors involved in tumor metastasis by regulation of EMT-activating signaling pathways. Various miRNAs are involved in the signaling pathways associated with TC metastasis which can be used as diagnostic and therapeutic biomarkers. Since, the miRNAs are sensitive, specific, and non-invasive, they can be suggested as efficient and optimal biomarkers of tumor invasion and metastasis. In the present review, we have summarized all of the miRNAs which have been significantly involved in thyroid tumor cells migration and invasion. We also categorized all of the reported miRNAs based on their cellular processes to clarify the molecular role of miRNAs during thyroid tumor cell migration and invasion. This review paves the way of introducing a non-invasive diagnostic and prognostic panel of miRNAs in aggressive and metastatic TC patients.

Micro-RNA let-7a-5p Derived From Mesenchymal Stem Cell-Derived Extracellular Vesicles Promotes the Regrowth of Neurons in Spinal-Cord-Injured Rats by Targeting the HMGA2/SMAD2 Axis

Spinal cord injury (SCI) often causes neuronal and axonal damage, resulting in permanent neurological impairments. Mesenchymal stem cells (MSCs) and extracellular vesicles (EVs) are promising treatments for SCI. However, the underlying mechanisms remain unclear. Herein, we demonstrated that EVs from bone marrow-derived MSCs promoted the differentiation of neural stem cells (NSCs) into the neurons and outgrowth of neurites that are extending into astrocytic scars in SCI rats. Further study found that let-7a-5p exerted a similar biological effect as MSC-EVs in regulating the differentiation of NSCs and leading to neurological improvement in SCI rats. Moreover, these MSC-EV-induced effects were attenuated by let-7a-5p inhibitors/antagomirs. When investigating the mechanism, bioinformatics predictions combined with western blot and RT-PCR analyses showed that both MSC-EVs and let-7a-5p were able to downregulate the expression of SMAD2 by inhibiting HMGA2. In conclusion, MSC-EV-secreted let-7a-5p promoted the regrowth of neurons and improved neurological recovery in SCI rats by targeting the HMGA2/SMAD2 axis.

Photocontrolled apoptosis induction using precursor miR-664a and an RNA carrier-conjugated with photosensitizer

Methods to spatially induce apoptosis are useful for cancer therapy. To control the induction of apoptosis, methods using light, such as photochemical internalization (PCI), have been developed. We hypothesized that photoinduced delivery of microRNAs (miRNAs) that regulate apoptosis could spatially induce apoptosis. In this study, we identified pre-miR-664a as a novel apoptosis-inducing miRNA via mitochondrial apoptotic pathway. Further, we demonstrated the utility of photoinduced cytosolic dispersion of RNA (PCDR), which is an intracellular RNA delivery method based on PCI. Indeed, apoptosis is spatially regulated by pre-miR-664a and PCDR. In addition, we found that apoptosis induced by pre-miR-664a delivered by PCDR was more rapid than that by lipofection. These results suggest that pre-miR-664a is a nucleic acid drug candidate for cancer therapy and PCDR and pre-miR-664a-based strategies have potential therapeutic uses for diseases affecting various cell types.

Induction of microRNA hsa-let-7d-5p, and repression of HMGA2, contribute protection against lipid accumulation in macrophage 'foam' cells

Accumulation of excess cholesterol and cholesteryl ester in macrophage 'foam' cells within the arterial intima characterises early 'fatty streak' atherosclerotic lesions, and is accompanied by epigenetic changes, including altered expression of microRNA sequences which determine of gene and protein expression. This study established that exposure to lipoproteins, including acetylated LDL, induced macrophage expression of microRNA hsa-let-7d-5p, a sequence previously linked with tumour suppression, and repressed expression of one of its target genes, high mobility group AT hook 2 (HMGA2). A let-7d-5p mimic repressed expression of HMGA2 (18%; p < 0.05) while a marked increase (2.9-fold; p < 0.05) in expression of HMGA2 was noted in the presence of let-7d-5p inhibitor. Under these conditions, let-7d-5p mimic significantly (p < 0.05) decreased total (10%), free (8%) and cholesteryl ester (21%) mass, while the inhibitor significantly (p < 0.05) increased total (29%) and free cholesterol (29%) mass, compared with the relevant controls. Let-7d-5p inhibition significantly (p < 0.05) increased endogenous biosynthesis of cholesterol (38%) and cholesteryl ester (39%) pools in macrophage 'foam' cells, without altering the cholesterol efflux pathway, or esterification of exogenous radiolabelled oleate. Let-7d-5p inhibition in sterol-loaded cells increased the level of HMGA2 protein (32%; p < 0.05), while SiRNA knockdown of this protein (29%; p < 0.05) resulted in a (21%, p < 0.05) reduction in free cholesterol mass. Thus, induction of let-7d-5p, and repression of its target HMGA2, in macrophages is a protective response to the challenge of increased cholesterol influx into these cells; dysregulation of this response may contribute to atherosclerosis and other disorders such as cancer.

hsa_circ_0062019 promotes the proliferation, migration, and invasion of prostate cancer cells via the miR-195-5p/HMGA2 axis

Circular RNA (circRNA) is a new class of non-coding RNA. It was reported that circRNA involves in the metastasis of cancer. The aim of this study is to explore the role and mechanism of circRNA hsa_circ_0062019 in the development of prostate cancer (PCa). Our results showed that hsa_circ_0062019 was highly expressed in PCa cell lines. Cell Counting Kit-8 assay revealed that upregulation of hsa_circ_0062019 boosted PCa cell proliferation, and silencing of hsa_circ_0062019 inhibited cell proliferation. Meanwhile, transwell assay proved that upregulation of hsa_circ_0062019 facilitated PCa cell invasion and migration, while downregulation of hsa_circ_0062019 inhibited these malignant phenotypes. Furthermore, luciferase reporter assay proved the binding of hsa_circ_0062019 with miR-195-5p and the binding between miR-195-5p and high mobility group AT-hook 2 (HMGA2), suggesting that hsa_circ_0062019 promoted the expression of HMGA2 by sponging miR-195-5p. In addition, our results revealed that the hsa_circ_0062019-induced PCa cell malignant phenotypes were notably reversed by the downregulation of HMGA2. Overall, our study demonstrated that hsa_circ_0062019 promoted PCa cell proliferation, migration, and invasion via upregulation of HMGA2 expression by sponging miR-195-5p. Our study proved a novel molecular mechanism of PCa development and provided a potential target for the treatment of PCa.

A Personalized Genomics Approach of the Prostate Cancer

Decades of research identified genomic similarities among prostate cancer patients and proposed general solutions for diagnostic and treatments. However, each human is a dynamic unique with never repeatable transcriptomic topology and no gene therapy is good for everybody. Therefore, we propose the Genomic Fabric Paradigm (GFP) as a personalized alternative to the biomarkers approach. Here, GFP is applied to three (one primary—“A”, and two secondary—“B” & “C”) cancer nodules and the surrounding normal tissue (“N”) from a surgically removed prostate tumor. GFP proved for the first time that, in addition to the expression levels, cancer alters also the cellular control of the gene expression fluctuations and remodels their networking. Substantial differences among the profiled regions were found in the pathways of P53-signaling, apoptosis, prostate cancer, block of differentiation, evading apoptosis, immortality, insensitivity to anti-growth signals, proliferation, resistance to chemotherapy, and sustained angiogenesis. ENTPD2, AP5M1 BAIAP2L1, and TOR1A were identified as the master regulators of the “A”, “B”, “C”, and “N” regions, and potential consequences of ENTPD2 manipulation were analyzed. The study shows that GFP can fully characterize the transcriptomic complexity of a heterogeneous prostate tumor and identify the most influential genes in each cancer nodule.

CSNK2A1-mediated phosphorylation of HMGA2 modulates cisplatin resistance in cervical cancer

The development of chemoresistance reduces the efficacy of anti-cancer drugs. Cervical cancer is still one of the most common cancer types in developing countries. The oncogenic protein high mobility group AT-hook 2 (HMGA2) is involved in the development and progression of tumors, although its role in chemoresistance of cervical cancer remains unclear. Here, we report that HMGA2 is highly expressed in cervical cancer and negatively correlated with cisplatin-induced cell death. We performed liquid chromatography-tandem mass spectrometry to demonstrate that HMGA2 has high potential to interact with casein kinase II A1 (CSNK2A1). Moreover, we observed that HMGA2 co-localizes with CSNK2A1 in the nucleus by immunofluorescence. Binding of HMGA2-CSNK2A1 was detected by immunoprecipitation assays. In addition, we identified that cisplatin induces an interaction between CSNK2A1 and HMGA2, thereby promoting the phosphorylation of HMGA2. CX-4945, a CSNK2A1 inhibitor, could inhibit the phosphorylation of HMGA2 and sensitize tumor cells to cisplatin. Our results reveal that CSNK2A1-dependent HMGA2 phosphorylation may partially underlie cisplatin-resistance in cervical cancer, suggesting that HMGA2 phosphorylation may have potential as a predicative biomarker and therapeutic target to improve chemotherapeutic efficacy.

MiR-142-3p targets HMGA2 and suppresses breast cancer malignancy

MicroRNAs (miRNAs) have the ability to regulate gene expression programs in cells. Hence, altered expression of miRNAs significantly contributes to breast cancer development and progression. Here, we demonstrate that the miRNA miR-142-3p directly targets the 3' untranslated region of HMGA2, which encodes an onco-embryonic protein that is overexpressed in most cancers, including breast cancer. Down regulation of miR-142-3p predicting poor patient survival in grade 3 breast cancer (P-value = 0.045). MiR-142-3p downregulates HMGA2 mRNA and protein levels. Higher miR-142-3p and lower HMGA2 expressed are found in breast cancer versus normal breast tissue (P-value<0.05), and their levels inversely correlate in breast cancers (P-value = 1.46 × 10^-4). We demonstrate that miR-142-3p induces apoptosis and G2/M cell cycle arrest in breast cancer cells. In addition, it inhibits breast cancer stem cell properties and decreases SOX2, NANOG, ALDH and c-Myc expression. MiR-142-3p also decreases cell proliferation through inhibition of the ERK/AKT/STAT3 signaling pathways. Finally, pathway analyses of patient samples suggest that these mechanisms also acting in the tumors of breast cancer patients. Thus, our work identifies HMGA2 as a direct miR-142-3p target and indicates that miR-142-3p is an important suppressor of breast cancer oncogenesis. This identifies miR-142-3p may candidate as a therapeutic molecule for breast cancer treatment.

Therapeutic Implications of TGFβ in Cancer Treatment: A Systematic Review

Simple Summary

While the importance of transforming growth factor β (TGFβ) in cancer development and progression has long been recognized, a successful therapy targeting this cytokine has not been developed yet. The difficulty in blocking the tumor-promoting activity of this factor while maintaining the tumor suppressor effects can compromise the expected outcomes. This systematic review summarizes and discusses the different strategies being tested to regulate TGFβ expression in cancer treatment, as well as their associated side effects.

Abstract

Transforming growth factor β (TGFβ) is a pleiotropic cytokine that participates in a wide range of biological functions. The alterations in the expression levels of this factor, or the deregulation of its signaling cascade, can lead to different pathologies, including cancer. A great variety of therapeutic strategies targeting TGFβ, or the members included in its signaling pathway, are currently being researched in cancer treatment. However, the dual role of TGFβ, as a tumor suppressor or a tumor-promoter, together with its crosstalk with other signaling pathways, has hampered the development of safe and effective treatments aimed at halting the cancer progression. This systematic literature review aims to provide insight into the different approaches available to regulate TGFβ and/or the molecules involved in its synthesis, activation, or signaling, as a cancer treatment. The therapeutic strategies most commonly investigated include antisense oligonucleotides, which prevent TGFβ synthesis, to molecules that block the interaction between TGFβ and its signaling receptors, together with inhibitors of the TGFβ signaling cascade-effectors. The effectiveness and possible complications of the different potential therapies available are also discussed.

HMGA2 promotes breast cancer metastasis by modulating Hippo-YAP signaling pathway

BACKGROUND

Breast cancer is the most common cancer in women, and triple-negative breast cancer (TNBC) accounts for about 15-20% of all breast cancer. High mobility group AT-hook 2 (HMGA2) is overexpressed in some tumors and closely associated with patients' prognosis. However, the mechanisms involved in the regulation of HMGA2 in TNBC still remain unclear.

METHODS

In this study, HMGA2 level in TNBC cell lines was analyzed by western blot. After knockdown of HMGA2 expression by RNA interference in TNBC cell lines MDA-MB-231 and SUM149, wound healing and transwell assays were conducted to examine the effects of HMGA2 on migration and invasion. Tumor metastasis was assessed in amouse xenograft model invivo. Furthermore, expression levels of epithelial-mesenchymal transition (EMT) biomarkers and involvement of the Hippo-YAP pathway were detected by western blot.

RESULTS

Compared to normal breast epithelial cells, the expression levels of HMGA2 were significantly increased in TNBC cell lines (all P< .05). Downregulation of HMGA2 dramatically inhibited the migration and invasion of MDA-MB-231 and SUM149 cells (all P< .01) invitro, and suppressed the tumor metastasis of nude mice xenograft model invivo. Western blot analysis revealed alterations in EMT biomarkers: the expression of mesenchymal markers N-cadherin, Vimentin and Snail were decreased, while the expression of epithelial marker E-cadherin was increased. Downregulated expression of HMGA2 attenuated Hippo-YAP related protein expression and the stability of YAP.

CONCLUSIONS

HMGA2 is highly expressed in TNBC cells. Downregulation of HMGA2 inhibits the migration and invasion of TNBC and invivo tumor metastasis mediated through inhibition of EMT and Hippo-YAP pathway.

MiR-581/SMAD7 Axis Contributes to Colorectal Cancer Metastasis: A Bioinformatic and Experimental Validation-Based Study

Metastasis is a well-known poor prognostic factor and primary cause of mortality in patients with colorectal cancer (CRC). Recently, with the progress of high through-put sequencing, aberrantly expressed non-coding RNAs (ncRNAs) were found to participate in the initiation and development of cancer. However, the mechanisms of ncRNA-mediated regulation of metastasis in CRC remain largely unknown. In this study, we systematically analyzed the expression network of microRNAs (miRNAs) and genes in CRC metastasis using bioinformatics, and discovered that the miR-581/SMAD7 axis could be a potential factor that drives CRC metastasis. A dual luciferase report assay and protein analysis confirmed the binding relationship between miR-581 and SMAD7. Further functional assays revealed that miR-581 inhibition could suppress cell proliferation and induce apoptosis in SW480 cells. Up-regulation or down-regulation of miR-581 could both affect cell invasion capacity and modulate epithelial to mesenchymal transition (EMT) via a SMAD7/TGFβ signaling pathway. In conclusion, our findings elucidated that miR-581/SMAD7 could be essential for CRC metastasis, and may serve as a potential therapeutic target for CRC patients.

Y Chromosome LncRNA Are Involved in Radiation Response of Male Non-Small Cell Lung Cancer Cells

Numerous studies have implicated changes in the Y chromosome in male cancers, yet few have investigated the biological importance of Y chromosome noncoding RNA. Here we identify a group of Y chromosome-expressed long noncoding RNA (lncRNA) that are involved in male non-small cell lung cancer (NSCLC) radiation sensitivity. Radiosensitive male NSCLC cell lines demonstrated a dose-dependent induction of linc-SPRY3-2/3/4 following irradiation, which was not observed in radioresistant male NSCLC cell lines. Cytogenetics revealed the loss of chromosome Y (LOY) in the radioresistant male NSCLC cell lines. Gain- and loss-of-function experiments indicated that linc-SPRY3-2/3/4 transcripts affect cell viability and apoptosis. Computational prediction of RNA binding proteins (RBP) motifs and UV-cross-linking and immunoprecipitation (CLIP) assays identified IGF2BP3, an RBP involved in mRNA stability, as a binding partner for linc-SPRY3-2/3/4 RNA. The presence of linc-SPRY3-2/3/4 reduced the half-life of known IGF2BP3 binding mRNA, such as the antiapoptotic HMGA2 mRNA, as well as the oncogenic c-MYC mRNA. Assessment of Y chromosome in NSCLC tissue microarrays and expression of linc-SPRY3-2/3/4 in NSCLC RNA-seq and microarray data revealed a negative correlation between the loss of the Y chromosome or linc-SPRY3-2/3/4 and overall survival. Thus, linc-SPRY3-2/3/4 expression and LOY could represent an important marker of radiotherapy in NSCLC. SIGNIFICANCE: This study describes previously unknown Y chromosome-expressed lncRNA regulators of radiation response in male NSCLC and show a correlation between loss of chromosome Y and radioresistance. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/19/4046/F1.large.jpg.

Oncogenic role of HMGA2 in fusion-negative rhabdomyosarcoma cells

Background

Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue sarcoma. There are two subtypes, fusion gene-positive RMS (FP-RMS) and fusion gene-negative RMS (FN-RMS), depending on the presence of a fusion gene, either PAX3-FOXO1 or PAX7-FOXO1. These fusion genes are thought to be oncogenic drivers of FP-RMS. By contrast, the underlying mechanism of FN-RMS has not been thoroughly investigated. It has recently been shown that HMGA2 is specifically positive in pathological tissue from FN-RMS, but the role of HMGA2 in FN-RMS remains to be clarified.

Methods

In this study, we used FN-RMS cell lines to investigate the function of HMGA2. Gene expression, cell growth, cell cycle, myogenic differentiation, tumor formation in vivo, and cell viability under drug treatment were assessed.

Results

We found that HMGA2 was highly expressed in FN-RMS cells compared with FP-RMS cells and that knockdown of HMGA2 in FN-RMS cells inhibited cell growth and induced G1 phase accumulation in the cell cycle and myogenic differentiation. Additionally, we showed using both gain-of-function and loss-of-function assays that HMGA2 was required for tumor formation in vivo. Consistent with these findings, the HMGA2 inhibitor netropsin inhibited the cell growth of FN-RMS.

Conclusions

Our results suggest that HMGA2 has important role in the oncogenicity of FP-RMS and may be a potential therapeutic target in patients with FN-RMS.

PHF19 mediated regulation of proliferation and invasiveness in prostate cancer cells

The Polycomb-like protein PHF19/PCL3 associates with PRC2 and mediates its recruitment to chromatin in embryonic stem cells. PHF19 is also overexpressed in many cancers. However, neither PHF19 targets nor misregulated pathways involving PHF19 are known. Here, we investigate the role of PHF19 in prostate cancer cells. We find that PHF19 interacts with PRC2 and binds to PRC2 targets on chromatin. PHF19 target genes are involved in proliferation, differentiation, angiogenesis, and extracellular matrix organization. Depletion of PHF19 triggers an increase in MTF2/PCL2 chromatin recruitment, with a genome-wide gain in PRC2 occupancy and H3K27me3 deposition. Transcriptome analysis shows that PHF19 loss promotes deregulation of key genes involved in growth, metastasis, invasion, and of factors that stimulate blood vessels formation. Consistent with this, PHF19 silencing reduces cell proliferation, while promotes invasive growth and angiogenesis. Our findings reveal a role for PHF19 in controlling the balance between cell proliferation and invasiveness in prostate cancer.

MicroRNA-98 targets HMGA2 to inhibit the development of retinoblastoma through mediating Wnt/β-catenin pathway

BACKGROUND

Recently, the incidence and mortality of retinoblastoma (RB) have gradually increased. Many studies support the pivotal role of microRNAs (miRNAs) in the pathogenesis of RB. Alternation of microRNA-98 (miR-98) expression has been detected in several cancers, excluding RB. This study was designed to assess the regulatory mechanisms of miR-98 in human RB.

METHODS

RT-qPCR and Western blot analysis were used to detect miR-98 and HMGA2 expression. The effects of miR-98 were explored using the CCK-8 and Transwell assays. Dual-luciferase reporter assay was performed to confirm the relationship between miR-98 and HMGA2.

RESULTS

In RB, downregulation of miR-98 was identified. Upregulation of miR-98 inhibited proliferation, invasion and migration of RB cells. Further, HMGA2 was confirmed as a direct target gene of miR-98. And knockdown of HMGA2 suppressed the progression of RB. Moreover, upregulation of HMGA2 reversed the suppressive effects in the development of RB. In addition, miR-98 also showed suppressive effect on EMT and Wnt/β-catenin pathway.

CONCLUSION

MiR-98 targets HMGA2 to act as a tumor suppressor in RB by mediating Wnt/β-catenin pathway.

Exploring the Potential of MicroRNA Let-7c as a Therapeutic for Prostate Cancer

Prostate cancer (PCa) is one of the leading causes of mortality worldwide and often presents with aberrant microRNA (miRNA) expression. Identifying and understanding the unique expression profiles could aid in the detection and treatment of this disease. This review aims to identify miRNAs as potential therapeutic targets for PCa. Three bio-informatic searches were conducted to identify miRNAs that are reportedly implicated in the pathogenesis of PCa. Only hsa-Lethal-7 (let-7c), recognized for its role in PCa pathogenesis, was common to all three databases. Three further database searches were conducted to identify known targets of hsa-let-7c. Four targets were identified, HMGA2, c-Myc (MYC), TRAIL, and CASP3. An extensive review of the literature was undertaken to assess the role of hsa-let-7c in the progression of other malignancies and to evaluate its potential as a therapeutic target for PCa. The heterogeneous nature of cancer makes it logical to develop mechanisms by which the treatment of malignancies is tailored to an individual, harnessing specific knowledge of the underlying biology of the disease. Resetting cellular miRNA levels is an exciting prospect that will allow this ambition to be realized.

HMGA2 and Bach-1 cooperate to promote breast cancer cell malignancy

During breast cancer progression, tumor cells acquire multiple malignant features. The transcription factors and cell cycle regulators high mobility group A2 (HMGA2) and BTB and CNC homology 1 (Bach-1) are overexpressed in several cancers, but the mechanistic understanding of how HMGA2 and Bach-1 promote cancer development has been limited. We found that HMGA2 and Bach-1 are overexpressed in breast cancer tissues and their expression correlates positively in tumors but not in normal tissues. Individual HMGA2 or Bach-1 knockdown downregulates expression of both proteins, suggesting a mutual stabilizing effect between the two proteins. Importantly, combined HMGA2 and Bach-1 knockdown additively decrease cell proliferation, migration, epithelial-to-mesenchymal transition, and colony formation, while promoting apoptotic cell death via upregulation of caspase-3 and caspase-9. First the first time, we show that HMGA2 and Bach-1 overexpression in tumors correlate positively and that the proteins cooperatively suppress a broad range of malignant cellular properties, such as proliferation, migration, clonogenicity, and evasion of apoptotic cell death. Thus, our observations suggest that combined targeting of HMGA2 and Bach1 may be an effective therapeutic strategy to treat breast cancer.

miR-16 regulates proliferation and apoptosis of pituitary adenoma cells by inhibiting HMGA2

Previous studies have revealed that elevated expression of high mobility group A2 (HMGA2) is closely associated with the occurrence of pituitary adenomas (PAs). The expression of microRNA (miR)-16 is deregulated in PA tissues. Bioinformatics analysis has demonstrated that there is a complementary region between seed region of miR-16 and 3'-untranslated region (3'-UTR) of HMGA2 gene. In the present study, it was investigated whether miR-16 may regulate the expression of HMGA2 and whether it is involved in the pathogenesis of PAs. A total of 52 patients with PAs were recruited. Normal brain tissues obtained from 12 patients with traumatic brain injury were used as controls. The association between miR-16 and HMGA2 was validated using dual-luciferase reporter gene assay. HP75 cells were cultured in vitro and divided into the following groups: miR control, miR-16 mimic, small interfering RNA (si)-negative control, si-HMGA2 and miR-16 mimic+si-HMGA2 groups. The expression of miR-16 and HMGA2 in HP75 cells was determined using qRT-PCR and western blot. Cell proliferation was detected using the Cell Counting Kit-8 assay and apoptosis was detected using the TdT-UTP nick end labeling assay. Compared with normal pituitary tissues, the expression of miR-16 in PA tissues was significantly decreased, while the mRNA and protein levels of HMGA2 were significantly increased. miR-16 targeted the 3'-UTR of HMGA2 gene and regulated the expression of HMGA2. Transfection with siRNAs targeting HMGA2 and/or miR-16 mimics inhibited the expression of HMGA2 and the proliferative ability of HP75 cells, whereas it increased apoptosis of HP75 cells. The downregulation of miR-16 and upregulation of HMGA2 were involved in the pathogenesis of PAs. Thus, it is hypothesized that miR-16 inhibited the proliferation and promoted apoptosis of HP75 cells by inhibiting HMGA2 expression.

microRNA-98 inhibits the proliferation, invasion, migration and promotes apoptosis of breast cancer cells by binding to HMGA2

Breast cancer is a major contributor leading to cancer death in females worldwide. The aim of the present study was to investigate the effects of microRNA-98 (miR-98) on the processes of cell proliferation, invasion, migration and apoptosis by binding to high-mobility group AT-hook 2 (HMGA2) in breast cancer. Breast cancer tissues and adjacent normal tissues were collected from 112 patients suffering from breast cancer. The target relationship between miR-98 and HMGA2 was verified by in connection with the bioinformatics website as well as a dual-luciferase reporter assay, both of which provided evidence indicating that HMGA2 was a target gene of miR-98. Human breast cancer MDA-MB-231 cells were treated with miR-98 mimics, miR-98 inhibitors, siRNA-HMGA2 or miR-98 inhibitors + siRNA-HMGA2. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry methods were performed to determine cell proliferation, cell cycle and apoptosis, respectively, while a Transwell assay was employed to detect cell migration and invasion. Breast cancer tissues exhibited decreased miR-98 expression, while increased expression levels of HMGA2 were recorded. The mRNA and protein expressions of HMGA2, cell proliferation, cells at the S phase, cell migration, invasion, expressions of matrix metalloproteinase (MMP)2 as well as MMP9 were all reduced in response to miR-98 mimics or siRNA-HMGA2, while a contradictory trend was observed in the miR-98 inhibitors group. In conclusion, the results of the study demonstrate that miR-98 inhibits cell proliferation, migration and invasion, while acting to promote apoptosis by negatively regulating HMGA2 in breast cancer.

Targeting HMGA protein inhibits retinoblastoma cell proliferation

We describe a novel synthetic strategy for conjugating HMGA2 siRNA and the HMGA aptamer to the nucleolin aptamer and nucleolin antibody, respectively. Our studies demonstrate that these conjugates inhibit cell proliferation in retinoblastoma cells.

A novel approach to target HMGA proteins in retinoblastoma using HMGA2 siRNA–nucleolin aptamer and HMGA aptamer–nucleolin antibody conjugates was developed.

Increased high-mobility group A2 correlates with lymph node metastasis and prognosis of non-small cell lung cancer

BACKGROUND

High-mobility group A2 (HMGA2) has been investigated to be associated with tumorigenesis; however, the expression pattern and clinical significance of HMGA2 in non-small cell lung cancer (NSCLC) remains poorly understood. The purpose of this study is to examine the expression of HMGA2 and to analyze its relationships with respect to clinico-pathological features and patient survival in NSCLC.

METHODS

The expression level of HMGA2 was examined by Western blot and immunohistochemistry in NSCLC cells and tissues. The relationship between HMGA2 expression and survival of NSCLC patients was calculated by a Kaplan-Meier method and the evaluation of risk factor was determined by the multiple regression analysis.

RESULTS

NSCLC tissues exhibited a higher expression level of HMGA2 compared to normal tissues (p< 0.05) and the expression level of HMGA2 was significantly associated with poor differentiation of NSCLC (p< 0.05), lymph node metastasis (p< 0.05) and advanced clinical stage (p< 0.05). Besides, HMGA2 was also confirmed to be elevated in NSCLC cells by Western blot. Moreover, increased expression of HMGA2 correlated with decreased survival of NSCLC patients (p< 0.05).

CONCLUSIONS

HMGA2 was highly expressed in NSCLC tissues and cells and its overexpression was correlated with low-grade differentiation, lymph node metastasis, advanced clinical stage and poor survival time of NSCLC, which suggested that it could serve as a potential molecular marker and prognostic index for NSCLC.

Knockdown of Cripto-1 inhibits the proliferation, migration, invasion, and angiogenesis in prostate carcinoma cells

Cripto-1 (CR-1) is a member of the epidermal growth factor-Cripto-1/FRL1/Cryptic gene family that plays a key role in the various malignant cancers. However, the role of CR-1 in prostate carcinoma (PCa) remains limited. The expression of CR-1 was down-regulated by small interfering RNA (siRNA). Western blot measured the expression levels of CR-1 and some related proteins. We performed Cell Counting Kit-8, 5-ethynyl-2-deoxyuridine (EdU) incorporation assay and flow cytometry to detect the cellular proliferation and cycle. The transwell assay was used to observe cellular migration and invasion. The ability of angiogenesis was evaluated by tube formation assay. Our results showed that CR-1 knockdown markedly inhibited cell proliferation and induced cycle arrest in G1 phase, as p21 and p27 were up-regulated, whereas cyclin D1 and cyclin E1 were diminished. Moreover, silencing of CR-1 dramatically inhibited cell migration and invasion, repressed matrix metalloproteinases, and disturbed epithelial-mesenchymal transition. CR-1 siRNA suppressed the secreted level of vascular endothelial growth factor, and reduced protein level of Vascular endothelial growth factor receptor 2. We further found that decreased CR-1 expression inhibited FAK/Src/PI3K and Wnt/b-catenin signalling in PCa cells. These results suggested CR-1 might be served as an effective therapeutic target in PCa.

Hypoxia stimulates invasion and migration of human cervical cancer cell lines HeLa/SiHa through the Rab11 trafficking of integrin αvβ3/FAK/PI3K pathway-mediated Rac1 activation

Hypoxia plays a key role in tumour cell survival, invasion, and metastasis. An increasing number of studies have attempted to characterize the tumour response to hypoxia and to identify predictive markers of disease. Here we show that hypoxia increases tumour cell invasion and migration by the modulation of Rab11, an important molecule for vesicular trafficking. In our study, we found that Rab11, together with the activation of Rac1, could stimulate invasion and migration of cervical cancer cell lines HeLa/SiHa in hypoxia. Activation of Rac1 activity by hypoxia seems to be central to carcinoma invasion. We also found that these effects could be related to the integrin αvβ3. In addition, we studied the molecular pathway for this process. Our results showed that in cervical cancer cell lines HeLa/SiHa, Rac1 activation in hypoxia could stimulate invasion and migration, and this process was mediated by integrin αvβ3-mediated FAK and PI3K phosphorylation. Furthermore, hypoxia induced a dramatic increase in αvβ3 integrin surface expression, and this increase is dependent on Rab11. In conclusion, our study might provide a new mechanism for the effect of hypoxia on stimulating cervical carcinoma invasion.

High glucose induces epithelial-mesenchymal transition and results in the migration and invasion of colorectal cancer cells

Diabetes mellitus (DM) is associated with an increased risk of colorectal cancer (CRC). Hyperglycemia, a chronic abnormality in diabetes, is an independent predictor of cancer-associated mortality in CRC. However, the underlying biological mechanism of hyperglycemia in CRC cells is largely unknown. In the present study, HCT-116 and HT-29 cell proliferation, apoptosis, migration and invasion were assessed. In addition, the expression of epithelial (E)-cadherin, vimentin and high-mobility group A protein 2 (HMGA2) were assessed using western blotting. The results demonstrated that high glucose (HG; 30 mmol/l) caused CRC cells to lose their epithelial morphology, with a decrease in E-cadherin and an increase in vimentin, suggesting epithelial-mesenchymal transition (EMT). Furthermore, HG significantly enhanced the cell migration and invasion of CRC cells and the expression of HMGA2. Transfection with HMGA2 small interfering RNA reversed the HG-induced changes to CRC cells. In addition, HG promoted CRC cell proliferation and suppressed apoptosis. The results of the present study suggest that hyperglycemia promotes EMT, proliferation, migration and invasion in CRC cells and may provide novel insights into the link between HG and CRC.

Glyoxalase 1 sustains the metastatic phenotype of prostate cancer cells via EMT control

Metastasis is the primary cause of death in prostate cancer (PCa) patients. Effective therapeutic intervention in metastatic PCa is undermined by our poor understanding of its molecular aetiology. Defining the mechanisms underlying PCa metastasis may lead to insights into how to decrease morbidity and mortality in this disease. Glyoxalase 1 (Glo1) is the detoxification enzyme of methylglyoxal (MG), a potent precursor of advanced glycation end products (AGEs). Hydroimidazolone (MG-H1) and argpyrimidine (AP) are AGEs originating from MG-mediated post-translational modification of proteins at arginine residues. AP is involved in the control of epithelial to mesenchymal transition (EMT), a crucial determinant of cancer metastasis and invasion, whose regulation mechanisms in malignant cells are still emerging. Here, we uncover a novel mechanism linking Glo1 to the maintenance of the metastatic phenotype of PCa cells by controlling EMT by engaging the tumour suppressor miR-101, MG-H1-AP and TGF-β1/Smad signalling. Moreover, circulating levels of Glo1, miR-101, MG-H1-AP and TGF-β1 in patients with metastatic compared with non-metastatic PCa support our in vitro results, demonstrating their clinical relevance. We suggest that Glo1, together with miR-101, might be potential therapeutic targets for metastatic PCa, possibly by metformin administration.

Transcriptional landscape of human cancers

The homogeneity and heterogeneity in somatic mutations, copy number alterations and methylation across different cancer types have been extensively explored. However, the related exploration based on transcriptome data is lacking. In this study we explored gene expression profiles across 33 human cancer types using The Cancer Genome Atlas (TCGA) data. We identified consistently upregulated genes (such as E2F1, EZH2, FOXM1, MYBL2, PLK1, TTK, AURKA/B and BUB1) and consistently downregulated genes (such as SCARA5, MYOM1, NKAPL, PEG3, USP2, SLC5A7 and HMGCLL1) across various cancers. The dysregulation of these genes is likely to be associated with poor clinical outcomes in cancer. The dysregulated pathways commonly in cancers include cell cycle, DNA replication, repair, and recombination, Notch signaling, p53 signaling, Wnt signaling, TGFβ signaling, immune response etc. We also identified genes consistently upregulated or downregulated in highly-advanced cancers compared to lowly-advanced cancers. The highly (low) expressed genes in highly-advanced cancers are likely to have higher (lower) expression levels in cancers than in normal tissue, indicating that common gene expression perturbations drive cancer initiation and cancer progression. In addition, we identified a substantial number of genes exclusively dysregulated in a single cancer type or inconsistently dysregulated in different cancer types, demonstrating the intertumor heterogeneity. More importantly, we found a number of genes commonly dysregulated in various cancers such as PLP1, MYOM1, NKAPL and USP2 which were investigated in few cancer related studies, and thus represent our novel findings. Our study provides comprehensive portraits of transcriptional landscape of human cancers.

miR‑539 suppresses proliferation and induces apoptosis in renal cell carcinoma by targeting high mobility group A2

Renal cell carcinoma (RCC) is one of the most common urinary malignancies with a high rate of morbidity. MicroRNAs (miRNAs) have been shown to be critical post-transcriptional regulators in tumorigenesis. The present study aimed to investigate the effect of miRNA (miR)-539 on the proliferation and apoptosis of RCC. The expression of miR-539 and high mobility group AT-hook 2(HMGA2) were examined in clinical RCC specimens. The 786-O RCC cell line was also used and was transfected with miR-539 mimics or inhibitors. The correlation between miR-539 and HMGA2 was confirmed using a luciferase reporter assay. Cell viability and apoptosis were detected using MTT and flow cytometry assays. The protein levels of HMGA2, AKT, phosphorylated (p)-AKT, mammalian target of rapamycin (mTOR) and p-mTOR were analyzed using western blot analysis. The results revealed that miR-539 was negatively correlated with the expression of HMGA2 in clinical RCC specimens. Further experiments identified HMGA2 as a direct target of miR-539. The overexpression of miR-539 downregulated the expression of HMGA2, reduced cell proliferation and promoted cell apoptosis, whereas the knockdown of miR-539 led to the opposite results. miR-539 also suppressed the phosphorylation of AKT and mTOR, without altering the levels of total AKT and mTOR. Taken together, the results of the present study indicated that miR-539 negatively regulated the expression of HMGA2 in clinical specimens and in vitro. miR539 inhibited cell proliferation and induced apoptosis in RCC cells. This regulatory effect of miR-539 may be associated with the AKT signaling pathway. Therefore, miR-539 may be used as a biomarker for predicting the progression of RCC.

HMGA2 facilitates epithelial-mesenchymal transition in renal cell carcinoma by regulating the TGF-β/Smad2 signaling pathway

High-mobility group AT-hook 2 (HMGA2), a member of the high mobility group family, has been reported to correlate with cancer progression. However, there is no report concerning the correlation between HMGA2 and metastasis in renal cell carcinoma. In the present study, we found that HMGA2 was highly expressed in five renal cell carcinoma cell lines compared with that in the normal renal tubular epithelial HK2 cell line. Additionally, HMGA2 facilitated cell migration and invasion of renal cell carcinoma cells, as evidenced by wound healing and Transwell assays. Subsequently, our results revealed that the E-cadherin level was upregulated, while N-cadherin, Twist1 and Twist2 expression were downregulated in HMGA2-depleted ACHN cells. In contrast, overexpression of HMGA2 in 786-O cells enhanced epithelial-mesenchymal transition (EMT). In addition, analysis of the database Cancer Browser further validated the positive correlation between HGMA2 and Twist1 or Twist2 in renal cell carcinoma. Meanwhile, Kaplan-Meier analysis indicated that low HMGA2 expression was closely associated with an increased overall survival in renal cell carcinoma patients. To confirm the underlying mechanism of HMGA2-regulated EMT, our results revealed that silencing of HMGA2 downregulated the mRNA and protein levels of TGF-β and Smad2, while HMGA2 overexpression had the opposite effect. Furthermore, TGF-β overexpression could partially reverse the anti-metastatic effect and mesenchymal-epithelial transition (MET) by HMGA2 loss, while TGF-β deficiency impeded the pro-metastatic phenotype and high expression of EMT markers induced by HMGA2 overexpression. In summary, our results demonstrated that HMGA2 facilitated a metastatic phenotype and the EMT process in renal cell carcinoma cells in vitro through a TGF-β-dependent pathway. In addition, these data strongly suggest that HGMA2 may serve as a potential therapeutic target and prognostic biomarker against renal cell carcinoma in the future.

Genome-wide association study reveals genetic loci and candidate genes for average daily gain in Duroc pigs

Objective

Average daily gain (ADG) is an important target trait of pig breeding programs. We aimed to identify single nucleotide polymorphisms (SNPs) and genomic regions that are associated with ADG in the Duroc pig population.

Methods

We performed a genome-wide association study involving 390 Duroc boars and by using the PorcineSNP60K Beadchip and two linear models.

Results

After quality control, we detected 3,5971 SNPs, which included seven SNPs that are significantly associated with the ADG of pigs. We identified six quantitative trait loci (QTL) regions for ADG. These QTLs included four previously reported QTLs on Sus scrofa chromosome (SSC) 1, SSC5, SSC9, and SSC13, as well as two novel QTLs on SSC6 and SSC16. In addition, we selected six candidate genes (general transcription factor 3C polypeptide 5, high mobility group AT-hook 2, nicotinamide phosphoribosyltransferase, oligodendrocyte transcription factor 1, pleckstrin homology and RhoGEF domain containing G4B, and ENSSSCG00000031548) associated with ADG on the basis of their physiological roles and positional information. These candidate genes are involved in skeletal muscle cell differentiation, diet-induced obesity, and nervous system development.

Conclusion

This study contributes to the identification of the casual mutation that underlies QTLs associated with ADG and to future pig breeding programs based on marker-assisted selection. Further studies are needed to elucidate the role of the identified candidate genes in the physiological processes involved in ADG regulation.

miR-125b-5p functions as a tumor suppressor gene partially by regulating HMGA2 in esophageal squamous cell carcinoma

MicroRNAs (miRNAs) play important roles in the progression of human cancer including esophageal squamous cell carcinoma (ESCC). Although previous reports showed that miR-125b-5p was down-regulated in ESCC, the roles and mechanisms of loss of function of miR-125b-5p in ESCC were still unknown. Using microRNA microarray and GEO datasets, we found and confirmed that miR-125b-5p was down-regulated in ESCC tissues. In-vitro assays showed that ectopic miR-125b-5p expression repressed cell proliferation, migration and invasion, and induced cell senescence. We also found that miR-125b-5p reduced the expressions of cell cycle regulatory genes including CCNA2, CCND1 and CCNE1, and regulated the markers of epithelial to mesenchymal transition (EMT) including E-cadherin, N-cadherin and EMT associated transcription factor Slug, and also decreased the MMPs including MMP2, MMP7 and MMP13. Furthermore, the candidate target gene HMGA2 was negatively regulated by miR-125b-5p both in mRNA and protein levels. Importantly, knockdown of HMGA2 partially phenocopied the effects of miR-125b-5p overexpression on cell cycle regulators and EMT markers. In conclusion, our results suggested that overexpression of miR-125b-5p inhibited cell proliferation, migration and invasion partially by down-regulating HMGA2 in ESCC.

Loss of endothelial cell-specific molecule 1 promotes the tumorigenicity and metastasis of prostate cancer cells through regulation of the TIMP-1/MMP-9 expression

The Endothelial cell specific molecule-1 (ESM1) protein has been involved in proliferation and metastatic progression in multiple tumors. However, there are no studies regarding the mechanism of ESM1 in prostate cancer. We found that ESM1 knockdown in prostate cancer cells resulted in increased cell proliferation and colony formation ability response evidenced by decreased expression of p21 and increased expression of cyclin D1 in prostate cancer cells. Moreover, we revealed that knockdown ESM1 also induced the epithelial-mesenchymal transition (EMT), motility and invasiveness in accordance with the upregulated the MMP-9 expression, while downregulated the TIMP-1 expression. Recombinant human (Rh) TIMP-1 significantly attenuated ESM1-mediated cell migration and invasion. Additionally, ESM1 knockdown increased in vivo tumorigenicity and metastasis of prostate cancer cells. These findings provide the first evidence that the imbalance of MMP-9/TIMP-1, is one of the regulation mechanisms by which ESM1 promotes tumorigenicity and metastasis of prostate cancer cells.

HMGA2 upregulation mediates Cd-induced migration and invasion in A549 cells and in lung tissues of mice

Cadmium (Cd) is a toxic metal widely found in a number of environmental matrices, and it induces serious adverse effects in various organs and tissues. In this study, the role of high mobility group A2 (HMGA2) in promoting migration and invasion in Cd-treated A549 cells and lung tissues of mice was investigated. Our findings showed that exposure to Cd (2 μM) for 48 h or subcutaneous injection of Cd daily for 6 weeks significantly enhanced the expression of matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-2 (MMP-2), phosphorylated focal adhesion kinase (p-FAK), and HMGA2 in A549 cells or lung tissues of mice. In A549 cells, HMGA2 knockdown significantly decreased expression of MMP-9, MMP-2 and p-FAK and inhibited the migration and invasion compared to that of only Cd-treated cultures. Overexpression of HMGA2 in HEK-293T cells increased expression of MMP-9, MMP-2 and p-FAK and enhanced the migration and invasion compared with the empty vector transfection group. In conclusion, upregulation of HMGA2 plays an important role in Cd-enhanced migration and invasion. Suppressing HMGA2 expression might have potential values in prevention of Cd-resulted toxicities.

HMGA2 regulates lung cancer proliferation and metastasis

BACKGROUND

This study aimed to explore the effects of HMGA2 on cell proliferation and metastases in lung cancer and its underlying mechanism.

METHODS

HMGA2 expression in lung cancer tissues and its association with overall survival were analyzed based on data from a public database. The roles of HMGA2 were validated via loss-of-function and gain-of-function experiments in vitro. HMGA2 regulation by microRNA-195 (miR-195) was validated by real time-PCR, Western blotting, and luciferase reporter assays.

RESULTS

HMGA2 was upregulated and associated with reduced overall survival in patients with lung adenocarcinoma. HMGA2 knockdown suppressed the proliferation and motility of H1299 cells, while HMGA2 ectopic expression in A549 cells increased cell proliferation and migration. HMGA2 affected cell apoptosis through caspase 3/9 and Bcl-2, and regulated epithelial-to-mesenchymal transition by targeting Twist 1. Moreover, miR-195 was found to directly target the 3' untranslated region of HMGA2 messenger RNA and suppress its expression in lung cancer.

CONCLUSION

This study demonstrated that HMGA2, regulated by miR-195, played important roles in proliferation, metastases, and epithelial-to-mesenchymal transition in lung cancer. HMGA2 might serve as a biomarker and potential therapeutic target for lung cancer treatment.

Angiotensin II type 2 receptor-interacting protein 3a inhibits ovarian carcinoma metastasis via the extracellular HMGA2-mediated ERK/EMT pathway

Local migration and long-distance metastasis is the main reason for higher mortality of ovarian cancer. Microtubule-associated tumor suppressor 1/angiotensin II type 2 receptor-interacting protein is associated with tumor initiation and progression and exerts anti-tumor effects. High mobility group AT-hook 2 is overexpressed in majority of metastatic carcinomas, which contributes to carcinomas metastasis through Snail-induced epithelial-to-mesenchymal transition signal pathway. The purpose of this study was to investigate the signal pathway of microtubule-associated tumor suppressor 1/angiotensin II type 2 receptor-interacting protein-mediated anti-tumor effects. Our data observed that ovarian carcinoma cells exhibited lower expression of angiotensin II type 2 receptor-interacting protein 3a and higher expression of high mobility group AT-hook 2 compared to normal ovarian cells. Restoration of angiotensin II type 2 receptor-interacting protein 3a expression in ovarian carcinoma cells inhibited high mobility group AT-hook 2 expression and exhibited anti-proliferative effects. In addition, angiotensin II type 2 receptor-interacting protein 3a treatment suppressed the phosphorylation of epithelial-to-mesenchymal transition and extracellular signal-regulated kinase in ovarian carcinoma cells. We also observed that angiotensin II type 2 receptor-interacting protein 3a restoration downregulated expression of Snail, E-Cadherin, N-Cadherin, and Vimentin in ovarian carcinoma cells, whereas angiotensin II type 2 receptor-interacting protein 3a knockdown enhanced the phosphorylation of extracellular signal-regulated kinase and epithelial-to-mesenchymal transition. In vivo assay indicated that angiotensin II type 2 receptor-interacting protein 3a inhibited ovarian tumor growth and elevated survival of tumor-bearing immunodeficient mice. Tumor histological analysis indicated that Snail, E-Cadherin, N-Cadherin, and Vimentin expression levels were downregulated via decreasing high mobility group AT-hook 2 expression. Furthermore, upregulation of angiotensin II type 2 receptor-interacting protein 3a impaired the phenotype of extracellular signal-regulated kinase and epithelial-to-mesenchymal transition in ovarian carcinoma cells and tumor tissues. Taken together, angiotensin II type 2 receptor-interacting protein 3a presents potential in suppressing the proliferation and aggressiveness of ovarian carcinoma cells through the high mobility group AT-hook 2-mediated extracellular signal-regulated kinase/epithelial-to-mesenchymal transition signal pathway.

Dovitinib enhances temozolomide efficacy in glioblastoma cells

The multikinase inhibitor and FDA‐approved drug dovitinib (Dov) crosses the blood–brain barrier and was recently used as single drug application in clinical trials for GB patients with recurrent disease. The Dov‐mediated molecular mechanisms in GB cells are unknown. We used GB patient cells and cell lines to show that Dov downregulated the stem cell protein Lin28 and its target high‐mobility group protein A2 (HMGA2). The Dov‐induced reduction in pSTAT3^Tyr705 phosphorylation demonstrated that Dov negatively affects the STAT3/LIN28/Let‐7/HMGA2 regulatory axis in GB cells. Consistent with the known function of LIN28 and HMGA2 in GB self‐renewal, Dov reduced GB tumor sphere formation. Dov treatment also caused the downregulation of key base excision repair factors and O⁶‐methylguanine‐DNA‐methyltransferase (MGMT), which are known to have important roles in the repair of temozolomide (TMZ)‐induced alkylating DNA damage. Combined Dov/TMZ treatment enhanced TMZ‐induced DNA damage as quantified by nuclear γH2AX foci and comet assays, and increased GB cell apoptosis. Pretreatment of GB cells with Dov (‘Dov priming’) prior to TMZ treatment reduced GB cell viability independent of p53 status. Sequential treatment involving ‘Dov priming’ and alternating treatment cycles with TMZ and Dov substantially reduced long‐term GB cell survival in MGMT+ patient GB cells. Our results may have immediate clinical implications to improve TMZ response in patients with LIN28⁺/HMGA2⁺GB, independent of their MGMT methylation status.

High expression of HMGA2 predicts poor survival in patients with clear cell renal cell carcinoma

High-mobility group AT-hook 2 (HMGA2) is involved in a wide spectrum of biological processes and is upregulated in several tumors, but its role in renal carcinoma remains unclear. The aim of this study was to examine the expression of HMGA2 and its relationship to the overall survival (OS) of patients with non-metastatic clear cell renal cell carcinoma (ccRCC) following surgery. The expression of HMGA2 was evaluated retrospectively by immunohistochemistry (IHC) in 162 patients with ccRCC who underwent nephrectomy in 2003 and 2004. An IHC analysis revealed that HMGA2 was expressed in the nuclei of tumor cells in 146 (90.1%) patients with ccRCC. The level of HMGA2 was positively correlated with tumor size, lymph node metastasis, and Fuhrman Grade. A Kaplan–Meier analysis with log-rank test found that patients with high HMGA2 expression had a poor outcome and that patients with low HMGA2 expression had better survival. Cox regression analysis showed that HMGA2 expression could serve as an independent prognostic factor for ccRCC patients. The efficacy of the following prognostic models was improved when HMGA2 expression was added: tumor node metastasis stage, UCLA Integrated Scoring System, Mayo Clinic stage, size, grade, and necrosis score. In summary, this study showed that HMGA2 expression is an independent prognostic factor for OS in patients with ccRCC. HMGA2 was found to be a valuable biomarker for ccRCC progression.