Prognostic Value of HMGA2 in Human Cancers: A Meta-Analysis Based on Literatures and TCGA Datasets

CircTHSD4 promotes the malignancy and docetaxel (DTX) resistance in prostate cancer by regulating miR-203/HMGA2 axis

Objective

Circular ribose nucleic acids (circRNAs) are implicated in tumor progression and drug resistance of prostate cancer (PCa). The current work explored the function of circ_0005203 (circTHSD4) in the malignancy and docetaxel (DTX) resistance of PCa.

Methods

circTHSD4 expression within PCa as well as matched non-carcinoma samples was measured through real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, a subcellular fraction assay was conducted to determine circTHSD4 subcellular localization within PCa cells. In addition, we performed a Western blot (WB) assay to detect high-mobility-group A2 protein (HMGA2) levels. Besides, functional associations of two molecules were investigated through dual luciferase reporter assay. Cell Counting Kit (CCK)-8, colony formation together with Transwell assay was conducted to assess malignant phenotypes of PCa cells, whereas flow cytometry was performed to determine cell apoptosis. Furthermore, a xenograft mouse model was constructed to verify the effect of circTHSD4 on the carcinogenesis of PCa cells.

Results

According to RT-qPCR results, circTHSD4 was up-regulated within PCa tissues and cells, which predicted the dismal prognostic outcome of PCa cases. circTHSD4 silencing within PCa cells markedly suppressed cell growth, migration, and colony formation. circTHSD4 silencing remarkably elevated PCa cell apoptosis and carcinogenesis within the xenograft model. Further, circTHSD4 silencing enhanced docetaxel (DTX) sensitivity in PCa cells. Furthermore, we demonstrated that circTHSD4 modulated the malignancy of PCa cells by regulating HMGA2 expression through sponging miR-203.

Conclusion

Together, our findings suggest that circTHSD4 overexpression could promote the malignant phenotype and DTX resistance in PCa through the regulation of the miR-203/HMGA2 axis.

Identification of HMGA2 as a predictive biomarker of response to bintrafusp alfa in a phase 1 trial in patients with advanced triple-negative breast cancer

Background

We report the clinical activity, safety, and identification of a predictive biomarker for bintrafusp alfa, a first-in-class bifunctional fusion protein composed of the extracellular domain of TGFβRII (a TGF-β "trap") fused to a human IgG1 mAb blocking PD-L1, in patients with advanced triple-negative breast cancer (TNBC).

Methods

In this expansion cohort of a global phase 1 study, patients with pretreated, advanced TNBC received bintrafusp alfa 1200 mg every 2 weeks intravenously until disease progression, unacceptable toxicity, or withdrawal. The primary objective was confirmed best overall response by RECIST 1.1 assessed per independent review committee (IRC).

Results

As of May 15, 2020, a total of 33 patients had received bintrafusp alfa, for a median of 6.0 (range, 2.0-48.1) weeks. The objective response rate was 9.1% (95% CI, 1.9%-24.3%) by IRC and investigator assessment. The median progression-free survival per IRC was 1.3 (95% CI, 1.2-1.4) months, and median overall survival was 7.7 (95% CI, 2.1-10.9) months. Twenty-five patients (75.8%) experienced treatment-related adverse events (TRAEs). Grade 3 TRAEs occurred in 5 patients (15.2%); no patients had a grade 4 TRAE. There was 1 treatment-related death (dyspnea, hemolysis, and thrombocytopenia in a patient with extensive disease at trial entry). Responses occurred independently of PD-L1 expression, and tumor RNAseq data identified HMGA2 as a potential biomarker of response.

Conclusions

Bintrafusp alfa showed clinical activity and manageable safety in patients with heavily pretreated advanced TNBC. HMGA2 was identified as a potential predictive biomarker of response.

ClinicalTrialsgov identifier

NCT02517398.

Cancer-Related Stigmatization, Quality of Life, and Fear of Death Among Newly Diagnosed Cancer Patients

The purpose of the study is to investigate the gender differences among newly diagnosed cancer patients from the cultural perspective of Pakistan. The data comprised two equal groups: men (50%) and women (50%). Most participants were 31-45 years old, and the duration of the cancer diagnosis was less than 6 months (74.6%). The data was collected on the following scales: the discrimination and stigma scale, the internalized stigma scale, the WHO-quality of life scale, and the fear of death scale. Data was analyzed using SPSS v.25; descriptive statistics, an independent sample t-test, and simple linear regression were applied to the data. The results revealed that men and women are both experiencing cancer-related stigmatization in Pakistan. However, women face a higher level of stigmatization, lower quality of life, and higher fear of death than men. Furthermore, the regression analysis result confirms that the cancer-related stigma faced by the diagnosed patients decreases the patient's quality of life and induces the fear of death.

Caspase-9b drives cellular transformation, lung inflammation, and lung tumorigenesis

Caspase 9 undergoes alternative splicing to produce two opposing isoforms: pro-apoptotic Caspase-9a (C9a) and pro-survival Caspase-9b (C9b). Previously, our laboratory reported that C9b is expressed in majority of non-small cell lung cancer tumors and directly activates the NF-κB pathway. In this study, the role of C9b in activation of the NF-κB pathway in vivo, lung inflammation and immune responses, and lung tumorigenesis were examined. Specifically, a transgenic mouse model expressing human C9b in the lung pneumocytes developed inflammatory lung lesions, which correlated with enhanced activation of the NF-κB pathway and increased influx of immunosuppressive MDSCs in contrast to wild-type mice. C9b mice presented with facial dermatitis, a thickened and disorganized dermis, enhanced collagen depth, and increased serum levels of IL-6. C9b mice also developed spontaneous lung tumors, and C9b cooperated with oncogenic KRAS in lung tumorigenesis. C9b expression also cooperated with oncogenic KRAS and p53 downregulation to drive the full cell transformation of human bronchial epithelial cells (e.g., tumor formation). Implications: Our findings show that C9b can directly activate NF-κB pathway in vivo to modulate lung inflammation, immune cell influx, and peripheral immune responses, which demonstrates that C9b is key factor in driving cell transformation and lung tumorigenesis.

Expression and Clinical Significance of High-Mobility Group AT-hook 2 (HMGA2) in Osteosarcoma

Objective

Although high‐mobility group AT‐hook 2 (HMGA2) has been shown to have crucial roles in the pathogenesis and metastasis of various malignancies, its expression and significance in osteosarcoma remain unknown. Here we evaluate the expression, clinical prognostic value, and overall function of HMGA2 in osteosarcoma.

Methods

Sixty‐nine osteosarcoma patient specimens within a tissue microarray (TMA) were analyzed by immunohistochemistry for HMGA2 expression. Demographics and clinicopathological information including age, gender, tumor location, metastasis, recurrence, chemotherapy response, follow‐up time, and disease status were also collected. After validation of expression, we determined whether there was a correlation between HMGA2 expression and patient clinicopathology. HMGA2 expression was also evaluated in osteosarcoma cell lines and patient tissues by Western blot, we analyzed the expression of HMGA2 in the human osteosarcoma cell lines MG63, 143B, U2OS, Saos‐2, MNNG/HOS, and KHOS. HMGA2‐specific siRNA and clonogenic assays were then used to determine the effect of HMGA2 inhibition on osteosarcoma cell proliferation, growth, and chemosensitivity.

Results

HMGA2 expression was elevated in the osteosarcoma patient specimens and human osteosarcoma cell lines. HMGA2 was differentially expressed in human osteosarcoma cell lines. Specifically, a relatively high expression of HMGA2 was present in KHOS, MNNG/HOS, 143B and a relatively low expression was in MG63, U2OS as well as Saos‐2. HMGA2 expression is correlated with metastasis and shorter overall survival. High HMGA2 expression is an independent predictor of poor osteosarcoma prognosis. There was no significant correlation between HMGA2 expression and the age, gender, or tumor site of the patient. HMGA2 expression is predominantly within the nucleus. The expression of HMGA2 also directly correlated to neoadjuvant chemoresistance. There was a significant reduction of HMGA2 expression in the siRNA transfection group. After the use of siRNA, the proliferation of osteosarcoma cells is decreased and the chemosensitivity of osteosarcoma cells is significantly increased.

Conclusion

Our study supports HMGA2 as a potential prognostic biomarker and therapeutic target in osteosarcoma.

A mechanistic basis for the malignant progression of salivary gland tumors

Salivary gland tumors are diverse neoplasms, likely reflecting differences in the tissue- and cell-of-origin. 80%-90% of tumors arising in the sublingual gland (SLG) are malignant, whereas the other major glands often form benign tumors. Owing to the lack of experimental models to explore the etiology of salivary gland tumors, the cellular and molecular bases of malignancy remain unknown. Here, we generated a murine model of HRASG12V-driven salivary gland tumors amenable to examine tumor onset and malignant progression. We found that HMGA2 marks the tumor onset, and transformed-SOX2+ stem/progenitor cells expand exclusively in SLG tumors. Lineage tracing experiments showed that SLG tumor cells undergo an extensive epithelial-mesenchymal transition (EMT) and TGF-β-responding tumor cells are a source of mesenchymal tumor cells invading the surrounding stroma. This study advances our understanding of the mechanistic basis of salivary gland malignancy and may help combat this highly heterogeneous cancer.

HMGA2 Supports Cancer Hallmarks in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that exhibits a high proliferation rate and early metastasis leading to a poor prognosis. HMGA2 is a DNA binding transcriptional regulator implicated in tumorigenesis. Here, we demonstrate that the HMGA2 promoter is demethylated in TNBC tumors, leading to increased expression of HMGA2 at both mRNA and protein levels. Importantly, high HMGA2 levels in TNBC tumors are correlated with poor prognosis. To detail the role of HMGA2 in TNBC development and progression, we studied its effect on core cancer phenotypes. Stable knockdown of HMGA2 in TNBC cells revealed that HMGA2 may support cell proliferation, cell migration and invasion. In addition, HMGA2 knockdown decreased cancer stem cell (CSC) features. Importantly, we found that silencing HMGA2 inhibited NF-kB signaling and lead to decreased expression of the downstream molecules IL-6 and IL-8 and reduced STAT3 pathway activation. Our results demonstrate that HMGA2 supports cancer hallmarks in TNBC and may represent a promising target for TNBC treatment.

CDK13-Mediated Cell Cycle Disorder Promotes Tumorigenesis of High HMGA2 Expression Gastric Cancer

The inhibitor of CDK4/6 has been clinically used for treating certain types of cancer which are characterized by G0/G1 acceleration induced by the CDK4/6-RB1 pathway. On the contrary, the cell cycle–related molecules are abnormal in over 50% of the patients with gastric cancer (GC), but the efficiency of inhibiting CDK4/6 does not work well as it is expected. In our study, we found HMGA2 promotes GC through accelerating the S–G2/M phase transition, instead of G0/G1. We also found CDK13 is the direct target gene of HMGA2. Importantly, we analyzed 200 pairs of GC and the adjacent tissue and proved the positive relation between HMGA2 and CDK13; moreover, high expression of both genes predicts a poorer prognosis than the expression of single gene does. We explored the effect of the novel CDK12/13 inhibiting agent, SR-4835, on high HMGA2 expression GC and found inhibition of both genes jointly could reach a satisfied result. Therefore, we suggest that inhibition of CDK13 and HMGA2 simultaneously could be an effective strategy for high HMGA2 expression GC. To detect the expression of both genes simultaneously and individually could be of benefit to predict prognosis for GC.

Prognostic significance of high mobility group A2 (HMGA2) in pancreatic ductal adenocarcinoma: malignant functions of cytoplasmic HMGA2 expression

PURPOSE

HMGA2 has frequently been found in benign as well as malignant tumors and a significant association between HMGA2 overexpression and poor survival in different malignancies was described. In pancreatic ductal adenocarcinoma (PDAC), nuclear HMGA2 expression is associated with tumor dedifferentiation and presence of lymph node metastasis. Nevertheless, the impact of HMGA2 occurrence in other cell compartments is unknown.

METHODS

Intracellular distribution of HMGA2 was analyzed in PDAC (n = 106) and peritumoral, non-malignant ducts (n = 28) by immunohistochemistry. Findings were correlated with clinico-pathological data. Additionally, intracellular HMGA2 presence was studied by Western blotting of cytoplasmic and nuclear fractions of cultured cells.

RESULTS

HMGA2 was found in the cytoplasm and in the nucleus of cultured cells. In human tumor tissue, HMGA2 was also frequently found in the cytoplasm and the nucleus of tumor cells, however, nuclear staining was generally stronger. Direct comparison from tumor tissue with corresponding non-neoplastic peritumoral tissue revealed significantly stronger expression in tumors (p = 0.003). Of note, the nuclear staining was significantly stronger in lymph node metastatic cell nuclei compared to primary tumor cell nuclei (p = 0.049). Interestingly, cytoplasmic staining positively correlated with lymph vessel (p = 0.004) and venous invasion (p = 0.046).

CONCLUSION

HMGA2 is a prognostic marker in PDAC. Firstly, we found a positive correlation for cytoplasmic HMGA2 expression with lympho-vascular invasion and, secondly, we found a significantly stronger nuclear expression of HMGA2 in cancer-positive lymph node nuclei compared to primary tumor cell nuclei. So far, the role of cytoplasmic HMGA2 is nearly unknown, however, our data lend support to the hypothesis that cytoplasmic HMGA2 expression is involved in nodal spread.

Genes involved in the epithelial-mesenchymal transition in oral cancer: A systematic review

OBJECTIVE

Epithelial-mesenchymal transition (EMT) is considered the initial step in the invasion-metastasis cascade. The aim of this systematic review was to study the signature of genes involved in the EMT process in oral cancer (OC) confirmed by protein expression and its possible relationship with oral squamous cell carcinoma (OSCC) prognostic variables.

MATERIALS AND METHODS

A search of the scientific literature was carried out with no start date restriction until 17 September 2020 in the electronic databases Pubmed/MEDLINE, Web of Science, Cochrane Library and Scopus, following specific eligibility criteria. The methodological quality of the included studies was assessed using the Newcastle-Ottawa tool.

RESULTS

A total of 8 retrospective cohort studies were included, all of them performed in China and with low risk of bias. Overexpression of the genes HNRNPC, ITGA5, HMGA2 and SRSF3, and low expression of ALDH3A1 and ARID2 promote EMT in OC. The more advanced clinical stages of the TNM classification were significantly associated with overexpression of HNRNPC, ITGA5, HMGA2 and SRSF3, and low expression of ARID2.

CONCLUSIONS

HNRNPC, ITGA5, HMGA2, SRSF3, ALDH3A1 and ARID2 genes were associated with EMT process. Over- or under-expression of these genes is associated with worse stages of OSCC and/or worse prognosis of the tumor. Further studies on this topic are needed in different countries to be able to confirm these results, since the detection of these genes can help to know which tumors have a worse prognosis.

CircFAM73A promotes the cancer stem cell-like properties of gastric cancer through the miR-490-3p/HMGA2 positive feedback loop and HNRNPK-mediated β-catenin stabilization

Background

Circular RNAs (circRNAs) have emerged as a new subclass of regulatory RNAs that play critical roles in various cancers. Cancer stem cells (CSCs), a small subset of cancer cells, are believed to possess the capacities to initiate tumorigenesis and promote progression. Although accumulating evidence has suggested that cells with CSC-like properties are crucial for the malignancy of gastric cancer (GC), it remains unclear whether circRNAs are related to the acquisition of CSC-like properties in GC.

Methods

CircFAM73A expression was analyzed by GEO datasets and verified in GC samples. The roles of circFAM73A in GC cell proliferation, migration, cisplatin resistance, and CSC-like properties were determined by a series of functional experiments both in vitro and in vivo. RNA pulldown was used to explore the miRNAs and proteins binding to circFAM73A. Bioinformatic analysis and experimental verification confirmed the downstream targets of circFAM73A. The regulation of circFAM73A by HMGA2 was verified by ChIP and RIP assays.

Results

Elevated circFAM73A expression was confirmed in GC tissues, and higher circFAM73A predicted poor prognosis in GC patients. The upregulation of circFAM73A enhanced CSC-like properties in GC, thus facilitating cell proliferation, migration, and cisplatin resistance. Mechanistically, circFAM73A promoted GC malignancy by regulating miR-490-3p/HMGA2 in a positive feedback loop and recruiting HNRNPK to facilitate β-catenin stabilization. Moreover, HMGA2 further enhanced E2F1 and HNRNPL activity, which in turn promoted circFAM73A expression.

Conclusions

Our work demonstrates the crucial role of circFAM73A in the CSC-like properties of GC and uncovers a positive feedback loop in circFAM73A regulation that leads to the progression of gastric cancer, which may provide new insights into circRNA-based diagnostic and therapeutic strategies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01896-9.

Potential Utility of Cell Free High Mobility Group AT-hook 2 (HMGA2) as a Prognostic Biomarker in Liquid Biopsies of Oral Squamous Cell Carcinoma

Background:

Locoregional spread is a frequent finding in oral cancer which dictates poor prognosis. HMGA2 expression has been linked to malignant traits of oral cancer in tissue biopsies however, data on HMGA2 expression in liquid biopsies in oral cancer is sparse. Purpose of this study was to explore prognostic relevance of HMGA2 in liquid biopsies of oral cancer patients.

Patients and Methods:

After obtaining approval from Institutional Review Board of Ziauddin University and informed written consent from study subjects, expression of circulating HMGA2 was evaluated in 96 OSCC cases and 100 age and sex matched controls via real time PCR using specific set of primers. We further analyzed relationship of various sociodemographic and clinicopathological variables with HMGA2expression and explored its prognostic potential.

Results:

Expression was seen in 22 (23%) cases. A higher expression was observed among subjects with local invasion (52.6% vs 47.4 %), distant metastasis (71.4% vs 28.6%) and tumor recurrence (57.1% vs 42.9%) p <0.05. Subjects having HMGA2 expression had a poor survival compared to HMGA2 negative (13.6% vs 35.4%), p <0.05.

Conclusion:

Circulating HMGA2 reflects presence of local invasion and distant metastasis and dictates poor prognosis in OSCC. It may contribute in categorizing high risk patients using a minimally invasive technique who are likely to benefit from targeted therapy.

Alterations in TGF-β signaling leads to high HMGA2 levels potentially through modulation of PJA1/SMAD3 in HCC cells

Recently, we observed that the TGF-β pathway is altered in 39% of HCCs. The alterations are correlated with a raised HMGA2 level. Therefore, we compared genetic alterations of HMGA2 and 43 TGF-β pathway core genes in HCC patients from TCGA database. Genetic alterations of 15 genes, including INHBE, INHBC, GDF11, ACVRL and TGFB2 out of 43 core genes, highly-moderately matched that of HMGA2. Co-occurrences of mutation amplification, gains, deletions and high/low mRNA of HMGA2 with those of the core genes were highly significant in INHBE, INHBC, ACVR1B, ACVRL and GDF11. Mass spectrometry studies revealed that HMGA2 interacted with an E3 ligase, PJA1, and that this interaction is enhanced by TGF-β treatment in the nuclear of HCC cells. Co-localization of nuclear PJA1 and HMGA2 in HCC cells increased upon TGF-β treatment. Raised HMGA2 levels that occur with alterations in the TGF-β signaling pathway may reflect an altered activity of E3 ligases, such as PJA1, and potentially contribute to the tumor-promoting roles of TGF-β signaling. Here, we report that the co-occurrence of genetic alterations in HMGA2 and TGF-β pathway core genes is implicated in HCC progression, and propose that HMGA2 and PJA1 may be potential novel targets in dysfunctional TGF-β signaling in HCC.

Cytoplasmic levels of high mobility group A2 determine survival prognoses in breast cancer patients

BACKGROUND

High mobility group A proteins are involved in chromatin remodeling, thereby influencing multiple fundamental biological processes. HMGA2 has been linked to oncogenic traits among a variety of malignancies.

OBJECTIVE

To determine the prognostic implications of subcellular distribution patterns of HMGA2 in breast cancer.

METHODS

Nuclear and cytoplasmic HMGA2 was evaluated in 342 breast cancer specimens and matched with clinico-pathological parameters.

RESULTS

Overall and cytoplasmic, but not nuclear, levels of HMGA2 correlated with better survival prognoses in our collective (hazard ratio (HR) 0.34, P = 0.001 and HR 0.34, P < 0.001, respectively). The protective effect of cytoplasmic HMGA2 persisted in the Luminal A and triple negative breast cancer subgroups. Evaluating Luminal A and B subgroups jointly, only cytoplasmic, but not overall or nuclear HMGA2 levels were associated with better survival (HR 0.42, 95% confidence interval 0.21, 0.86, P = 0.017), irrespective of tumor size and node status. The addition of HMGA2 overall and cytoplasmic scores strengthened the prognostic selectivity in a model of conventional breast cancer risk factors. No predictive significance with regard to endocrine or chemoendocrine therapies was observed.

CONCLUSION

Unexpectedly, we found a favorable survival probability upon overall levels of HMGA2 in our breast cancer collective, which was predominantly determined by the presence of HMGA2 in the cytoplasm.

The Prominent Role of HMGA Proteins in the Early Management of Gastrointestinal Cancers

GI tumors represent a heterogeneous group of neoplasms concerning their natural history and molecular alterations harbored. Nevertheless, these tumors share very high incidence and mortality rates worldwide and patients' poor prognosis. Therefore, the identification of specific biomarkers could increase the development of personalized medicine, in order to improve GI cancer management. In this sense, HMGA family members (HMGA1 and HMGA2) comprise an important group of genes involved in the genesis and progression of malignant tumors. Additionally, it has also been reported that HMGA1 and HMGA2 display an important role in the detection and progression of GI tumors. In this way, HMGA family members could be used as reliable biomarkers able to efficiently track not only the tumor per se but also the main risk conditions related with their development of GI cancers in the future. Finally, it shall be a promising option to revert the current scenario, once HMGA genes and proteins could represent a convergence point in the complex landscape of GI tumors.

An Integrated Bioinformatics Analysis Repurposes an Antihelminthic Drug Niclosamide for Treating HMGA2-Overexpressing Human Colorectal Cancer

Aberrant overexpression of high mobility group AT-hook 2 (HMGA2) is frequently found in cancers and HMGA2 has been considered an anticancer therapeutic target. In this study, a pan-cancer genomics survey based on Cancer Cell Line Encyclopedia (CCLE) and The Cancer Genome Atlas (TCGA) data indicated that HMGA2 was mainly overexpressed in gastrointestinal cancers including colorectal cancer. Intriguingly, HMGA2 overexpression had no prognostic impacts on cancer patients’ overall and disease-free survivals. In addition, HMGA2-overexpressing colorectal cancer cell lines did not display higher susceptibility to a previously identified HMGA2 inhibitor (netroposin). By microarray profiling of HMGA2-driven gene signature and subsequent Connectivity Map (CMap) database mining, we identified that S100 calcium-binding protein A4 (S100A4) may be a druggable vulnerability for HMGA2-overexpressing colorectal cancer. A repurposing S100A4 inhibitor, niclosamide, was found to reverse the HMGA2-driven gene signature both in colorectal cancer cell lines and patients’ tissues. In vitro and in vivo experiments validated that HMGA2-overexpressing colorectal cancer cells were more sensitive to niclosamide. However, inhibition of S100A4 by siRNAs and other inhibitors was not sufficient to exert effects like niclosamide. Further RNA sequencing analysis identified that niclosamide inhibited more cell-cycle-related gene expression in HMGA2-overexpressing colorectal cancer cells, which may explain its selective anticancer effect. Together, our study repurposes an anthelminthic drug niclosamide for treating HMGA2-overexpression colorectal cancer.

MicroRNA-9 exerts antitumor effects on hepatocellular carcinoma progression by targeting HMGA2

Accumulating evidence has demonstrated that the aberrant expression of microRNAs (miRs or miRNAs) may contribute to the initiation and progression of various types of human cancer and may also constitute biomarkers for cancer diagnosis and therapy. However, the specific function of miR‐9 in hepatocellular carcinoma (HCC) remains unclear, and the mechanisms that underlie HCC are incompletely understood. Here, we report that miR‐9 expression was significantly decreased in clinical tumor tissue samples, as well as in a cohort of HCC cell lines. In addition, it was demonstrated that overexpression of miR‐9 suppressed the proliferative and migratory capacity of HCC cells and impaired cell cycle progression. Furthermore, high mobility group AT‐hook 2 (HMGA2) was verified as a downstream target gene of miR‐9 using a luciferase reporter assay. Quantitative RT‐PCR and western blotting implicated HMGA2 in the miR‐9‐mediated reduction of HCC cell growth. In vivo, transfection with miR‐9 mimics down‐regulated the expression of HMGA2, thus leading to a dramatic reduction in tumor growth in a mouse xenograft model. These results suggest that miR‐9 may exert critical antitumor effects on HCC by directly targeting HMGA2, and the miR9/HMGA2 signaling pathway may be of use for the diagnosis and prognosis of patients with HCC.

CXCL12-regulated miR-370-3p functions as a tumor suppressor gene by targeting HMGA2 in nonfunctional pituitary adenomas

Silencing of noncoding genes within the imprinted DLK1-MEG3 locus is exclusive to human nonfunctional pituitary adenomas (NFPAs), but the exact mechanism is still unclear. This study was designed to demonstrate the impact of CXCL12 on the expression of miRNAs within this locus and phenotypic alterations of NFPAs. Human NFPA samples were collected for screening differentially expressed miRNAs by CXCL12. Target mRNAs of the miRNAs were predicted and verified in vitro. Tumor phenotypic alterations were also tested. Another 51 NFPA samples were enrolled to examine the correlation and clinical features. The expression of miR-370 was decreased by CXCL12 treatment in NFPAs. miR-370-3p was predicted and verified to target HMGA2 as a tumor suppressor gene. Overexpression of HMGA2 inhibited its antitumor function. miR-370-3p was downregulated and HMGA2 was upregulated significantly in High grade NFPAs. In conclusion, the CXCL12/miR-370-3p/HMGA2 signaling pathway is involved in tumor growth and invasiveness of NFPAs.