HMGA2 Contributes to Distant Metastasis and Poor Prognosis by Promoting Angiogenesis in Oral Squamous Cell Carcinoma

Decoding high mobility group A2 protein expression regulation and implications in human cancers

High Mobility Group A2 (HMGA2) oncofetal proteins are a distinct category of Transcription Factors (TFs) known as "architectural factors" due to their lack of direct transcriptional activity. Instead, they modulate the three-dimensional structure of chromatin by binding to AT-rich regions in the minor grooves of DNA through their AT-hooks. This binding allows HMGA2 to interact with other proteins and different regions of DNA, thereby regulating the expression of numerous genes involved in carcinogenesis. Consequently, multiple mechanisms exist to finely control HMGA2 protein expression at various transcriptional levels, ensuring precise concentration adjustments to maintain cellular homeostasis. During embryonic development, HMGA2 protein is highly expressed but becomes absent in adult tissues. However, recent studies have revealed its re-elevation in various cancer types. Extensive research has demonstrated the involvement of HMGA2 protein in carcinogenesis at multiple levels. It intervenes in crucial processes such as cell cycle regulation, apoptosis, angiogenesis, epithelial-to-mesenchymal transition, cancer cell stemness, and DNA damage repair mechanisms, ultimately promoting cancer cell survival. This comprehensive review provides insights into the HMGA2 protein, spanning from the genetic regulation to functional protein behavior. It highlights the significant mechanisms governing HMGA2 gene expression and elucidates the molecular roles of HMGA2 in the carcinogenesis process.

High Mobility Group AT-hook 2: A Biomarker Associated with Resistance to Enzalutamide in Prostate Cancer Cells

Metastatic prostate cancer (mPCa) is a leading cause of mortality, partly due to its resistance to anti-androgens like enzalutamide. Snail can promote this resistance by increasing full-length AR and AR-V7. High Mobility Group AT-hook 2 (HMGA2), a DNA-binding protein upstream of Snail, is crucial in proliferation and epithelial-mesenchymal transition (EMT). This study examines HMGA2's role in enzalutamide resistance. LNCaP and 22Rv1 cells overexpressing wild-type HMGA2, but not truncated HMGA2, showed EMT. Both variants led to a decreased sensitivity to enzalutamide but not alisertib compared to Neo control cells. The overexpression of HMGA2 did not alter AR expression. Enzalutamide-resistant C4-2B cells (C4-2B MDVR) had higher HMGA2 and AR/AR variant expression than enzalutamide-sensitive C4-2B cells but remained sensitive to alisertib. The HMGA2 knockdown in C4-2B MDVR cells increased sensitivity to both enzalutamide and alisertib without changing AR expression. A clinical analysis via cBioPortal revealed HMGA2 alterations in 3% and AR alterations in 59% of patients. The HMGA2 changes were linked to treatments like enzalutamide, abiraterone, or alisertib, with amplifications more prevalent in bone, lymph node, and liver metastases. Conclusively, HMGA2 is a potential biomarker for enzalutamide resistance in mPCa, independent of Snail and AR signaling, and alisertib may be an effective treatment for mPCa that expresses HMGA2.

Dysregulation of TCONS_00006091 contributes to the elevated risk of oral squamous cell carcinoma by upregulating SNAI1, IRS and HMGA2

In this study, we aimed to study the role of TCONS_00006091 in the pathogenesis of oral squamous cellular carcinoma (OSCC) transformed from oral lichen planus (OLP). This study recruited 108 OSCC patients which transformed from OLP as the OSCC group and 102 OLP patients with no sign of OSCC as the Control group. ROC curves were plotted to measure the diagnostic values of TCONS_00006091, miR-153, miR-370 and let-7g, and the changes in gene expressions were measured by RT-qPCR. Sequence analysis and luciferase assays were performed to analyze the molecular relationships among these genes. Cell proliferation and apoptosis were observed via MTT and FCM. TCONS_00006091 exhibited a better diagnosis value for OSCC transformed from OLP. OSCC group showed increased TCONS_00006091 expression and decreased expressions of miR-153, miR-370 and let-7g. The levels of SNAI1, IRS and HMGA2 was all significantly increased in OSCC patients. And TCONS_00006091 was found to sponge miR-153, miR-370 and let-7g, while these miRNAs were respectively found to targe SNAI1, IRS and HMGA2. The elevated TCONS_00006091 suppressed the expressions of miR-153, miR-370 and let-7g, leading to the increased expression of SNAI1, IRS and HMGA2. Also, promoted cell proliferation and suppressed apoptosis were observed upon the over-expression of TCONS_00006091. This study demonstrated that the expressions of miR-153, miR-370 and let-7g were down-regulated by the highly expressed TCONS_00006091 in OSCC patients, which accordingly up-regulated the expressions of SNAI1, IRS and HMGA2, resulting in the promoted cell proliferation and suppressed cell apoptosis.

Genes involved in metastasis in oral squamous cell carcinoma: A systematic review

Background and Aims

Oral squamous cell carcinoma is the most prevalent malignancy in the oral cavity, with a significant mortality rate. In oral squamous cell carcinoma patients, the survival rate could decrease because of delayed diagnosis. Thus, prevention, early diagnosis, and appropriate treatment can effectively increase the survival rate in patients. In this systematic review, we discussed the role of different genes in oral squamous cell carcinoma metastasis. Herein, we aimed to summarize clinical results, regarding the potential genes that promote oral squamous cell carcinoma metastasis.

Methods

This systematic review was carried out under the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. An electronic search for all relevant articles published in English between January 2018 and April 2022 was performed using Scopus, PubMed, and Google Scholar search engines. All original studies published in English were included, and we excluded studies that were in a non-English language.

Results

A total of 4682 articles were found, of which 14 were relevant and detected significant genes in oral squamous cell carcinoma progression. These findings investigated the overexpression of interferon-induced proteins with tetratricopeptide repeats 1 and 3 (IFIT1, IFT3), high-mobility group A2 (HMGA2), transformed growth factor-beta-induced, lectin galactoside-binding soluble 3 binding protein (LGALS3BP), bromodomain containing 4, COP9 signaling complex 6, heterogeneous nuclear ribonucleoproteins A2B1 (HNRNPA2B1), 5'-3' exoribonuclease 2 (XRN2), cystatin-A (CSTA), fibroblast growth factors 8 (FGF8), forkhead box P3, cadherin-3, also known as P-cadherin and Wnt family member 5A, ubiquitin-specific-processing protease 7, and retinoic acid receptor responder protein 2 genes lead to promote metastasis in oral squamous cell carcinoma. Overexpression of some genes (IFIT1, 3, LGALS3BP, HMGA2, HNRNPA2B1, XRN2, CSTA, and FGF8) was proven to be correlated with poor survival rates in oral squamous cell carcinoma patients.

Conclusion

Studies suggest that metastatic genes indicate a poor prognosis for oral squamous cell carcinoma patients. Detecting these metastatic genes in oral squamous cell carcinoma patients may be of predictive value and can also facilitate assessing oral squamous cell carcinoma development and its response to treatment.

HMGA2 promotes cancer metastasis by regulating epithelial-mesenchymal transition

Epithelial-mesenchymal transition (EMT) is a complex physiological process that transforms polarized epithelial cells into moving mesenchymal cells. Dysfunction of EMT promotes the invasion and metastasis of cancer. The architectural transcription factor high mobility group AT-hook 2 (HMGA2) is highly overexpressed in various types of cancer (e.g., colorectal cancer, liver cancer, breast cancer, uterine leiomyomas) and significantly correlated with poor survival rates. Evidence indicated that HMGA2 overexpression markedly decreased the expression of epithelial marker E-cadherin (CDH1) and increased that of vimentin (VIM), Snail, N-cadherin (CDH2), and zinc finger E-box binding homeobox 1 (ZEB1) by targeting the transforming growth factor beta/SMAD (TGFβ/SMAD), mitogen-activated protein kinase (MAPK), and WNT/beta-catenin (WNT/β-catenin) signaling pathways. Furthermore, a new class of non-coding RNAs (miRNAs, circular RNAs, and long non-coding RNAs) plays an essential role in the process of HMGA2-induced metastasis and invasion of cancer by accelerating the EMT process. In this review, we discuss alterations in the expression of HMGA2 in various types of cancer. Furthermore, we highlight the role of HMGA2-induced EMT in promoting tumor growth, migration, and invasion. More importantly, we discuss extensively the mechanism through which HMGA2 regulates the EMT process and invasion in most cancers, including signaling pathways and the interacting RNA signaling axis. Thus, the elucidation of molecular mechanisms that underlie the effects of HMGA2 on cancer invasion and patient survival by mediating EMT may offer new therapeutic methods for preventing cancer progression.

HMGA2 promotes nasopharyngeal carcinoma progression and is associated with tumor resistance and poor prognosis

Nasopharyngeal carcinoma (NPC), as one of the most prevalent malignancies in the head and neck region, still lacks a complete understanding of its pathogenesis. Presently, radiotherapy, concurrent chemoradiotherapy, and targeted therapy stand as the primary modalities for treating NPC. With advancements in medicine, the cure rates for nasopharyngeal carcinoma have been steadily increasing. Nevertheless, recurrence and metastasis persist as the primary reasons for treatment failure. Consequently, a profound exploration of the molecular mechanisms underlying the occurrence and progression of nasopharyngeal carcinoma, along with the exploration of corresponding therapeutic approaches, becomes particularly imperative in the quest for comprehensive solutions to combat this disease. High mobility group AT-hook 2 (HMGA2) is a pivotal protein capable of altering chromatin structure, regulating gene expression, and influencing transcriptional activity. In the realm of cancer research, HMGA2 exhibits widespread dysregulation, playing a crucial role in nearly all malignant tumors. It is implicated in various tumorigenic processes, including cell cycle regulation, cell proliferation, epithelial-mesenchymal transition, angiogenesis, tumor invasion, metastasis, and drug resistance. Additionally, HMGA2 serves as a molecular marker and an independent prognostic factor in certain malignancies. Recent studies have increasingly unveiled the critical role of HMGA2 in nasopharyngeal carcinoma (NPC), particularly in promoting malignant progression, correlating with tumor resistance, and serving as an independent adverse prognostic factor. This review focuses on elucidating the oncogenic role of HMGA2 in NPC, suggesting its potential association with chemotherapy resistance in NPC, and proposing its candidacy as an independent factor in nasopharyngeal carcinoma prognosis assessment.

Copper-containing titanium alloys promote the coupling of osteogenesis and angiogenesis by releasing copper ions

Previous investigations have reported on the ability of copper (Cu)-bearing biomaterials to accelerate vascular formation and bone regeneration. However, few studies have explored the effects of Cu-bearing materials on the interactions between angiogenesis and osteogenesis. Therefore, in this study, we prepared Cu-containing alloys using selective laser melting (SLM) technology and investigated the impact of preosteoblasts seeded on Ti6Al4V-4.5Cu alloy on angiogenesis. Our results indicated that Ti6Al4V-4.5Cu alloys increased the expression of proangiogenic genes and proteins in preosteoblasts, which further stimulated vascular formation in endothelial cells. Besides, we discovered that the biological effects of the Ti6Al4V-4.5Cu alloy were partly attributed to the release of Cu ions. In short, our research demonstrated the ability of Ti6Al4V-4.5Cu alloys to promote the coupling of angiogenesis and osteogenesis by releasing Cu ions.

Oral squamous cell carcinomas: state of the field and emerging directions

Oral squamous cell carcinoma (OSCC) develops on the mucosal epithelium of the oral cavity. It accounts for approximately 90% of oral malignancies and impairs appearance, pronunciation, swallowing, and flavor perception. In 2020, 377,713 OSCC cases were reported globally. According to the Global Cancer Observatory (GCO), the incidence of OSCC will rise by approximately 40% by 2040, accompanied by a growth in mortality. Persistent exposure to various risk factors, including tobacco, alcohol, betel quid (BQ), and human papillomavirus (HPV), will lead to the development of oral potentially malignant disorders (OPMDs), which are oral mucosal lesions with an increased risk of developing into OSCC. Complex and multifactorial, the oncogenesis process involves genetic alteration, epigenetic modification, and a dysregulated tumor microenvironment. Although various therapeutic interventions, such as chemotherapy, radiation, immunotherapy, and nanomedicine, have been proposed to prevent or treat OSCC and OPMDs, understanding the mechanism of malignancies will facilitate the identification of therapeutic and prognostic factors, thereby improving the efficacy of treatment for OSCC patients. This review summarizes the mechanisms involved in OSCC. Moreover, the current therapeutic interventions and prognostic methods for OSCC and OPMDs are discussed to facilitate comprehension and provide several prospective outlooks for the fields.

Diagnostic, Prognostic, and Therapeutic Role for Angiogenesis Markers in Head and Neck Squamous Cell Carcinoma: A Narrative Review

Despite refinements to diagnostic and therapeutic approaches over the last two decades, the outcome of patients with head and neck squamous cell carcinoma (HNSCC) has not shown substantial improvements, especially regarding those with advanced-stage disease. Angiogenesis is believed to be a turning point in the development of solid tumors, being a premise for mass growth and potential distant dissemination. Cancer-induced angiogenesis is a result of increased expression of angiogenic factors, decreased expression of anti-angiogenic factors, or a combination of both. The assessment of angiogenesis has also emerged as a potentially useful biological prognostic and predictive factor in HNSCC. The aim of this review is to assess the level of current knowledge on the neo-angiogenesis markers involved in the biology, behavior, and prognosis of HNSCC. A search (between 1 January 2012 and 10 October 2022) was run in PubMed, Scopus, and Web of Science electronic databases. After full-text screening and application of inclusion/exclusion criteria, 84 articles are included. The current knowledge and debate on angiogenesis in HNSCC presented in the eligible articles are stratified as follows: (i) diagnostic markers; (ii) prognostic markers; (iii) predictive markers; and (iv) markers with a potential therapeutic role. Angiogenesis is a biological and pathological indicator of malignancies progression and has negative implications in prognosis of some solid tumors; several signals capable of tripping the "angiogenic switch" have also been identified in HNSCC. Although several studies suggested that antiangiogenic agents might be a valuable adjunct to conventional chemo-radiation of HNSCC, their long-term therapeutic value remains uncertain. Further investigations are required on combinations of antiangiogenic agents with conventional chemotherapeutic ones, immunotherapeutic and molecularly targeted agents in HNSCC. Additional data are necessary to pinpoint which patients could benefit most from these treatments.

Histone lysine methyltransferase SMYD3 promotes oral squamous cell carcinoma tumorigenesis via H3K4me3-mediated HMGA2 transcription

BACKGROUND

Epigenetic dysregulation is essential to the tumorigenesis of oral squamous cell carcinoma (OSCC). SET and MYND domain-containing protein 3 (SMYD3), a histone lysine methyltransferase, is implicated in gene transcription regulation and tumor development. However, the roles of SMYD3 in OSCC initiation are not fully understood. The present study investigated the biological functions and mechanisms involved in the SMYD3-mediated tumorigenesis of OSCC utilizing bioinformatic approaches and validation assays with the aim of informing the development of targeted therapies for OSCC.

RESULTS

429 chromatin regulators were screened by a machine learning approach and aberrant expression of SMYD3 was found to be closely associated with OSCC formation and poor prognosis. Data profiling of single-cell and tissue demonstrated that upregulated SMYD3 significantly correlated with aggressive clinicopathological features of OSCC. Alterations in copy number and DNA methylation patterns may contribute to SMYD3 overexpression. Functional experimental results suggested that SMYD3 enhanced cancer cell stemness and proliferation in vitro and tumor growth in vivo. SMYD3 was observed to bind to the High Mobility Group AT-Hook 2 (HMGA2) promoter and elevated tri-methylation of histone H3 lysine 4 at the corresponding site was responsible for transactivating HMGA2. SMYD3 also was positively linked to HMGA2 expression in OSCC samples. Furthermore, treatment with the SMYD3 chemical inhibitor BCI-121 exerted anti-tumor effects.

CONCLUSIONS

Histone methyltransferase activity and transcription-potentiating function of SMYD3 were found to be essential for tumorigenesis and the SMYD3-HMGA2 is a potential therapeutic target in OSCC.

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.

Endothelial miR-196b-5p regulates angiogenesis via the hypoxia/miR-196b-5p/HMGA2/HIF1α loop

Angiogenesis is involved in development, reproduction, wound healing, homeostasis, and other pathophysiological events. Imbalanced angiogenesis predisposes patients to various pathological processes, such as angiocardiopathy, inflammation, and tumorigenesis. MicroRNAs (miRNAs) have been found to be important in regulating cellular processing and physiological events including angiogenesis. However, the role of miRNAs that regulate angiogenesis (angiomiRs) is not fully understood. Here, we observed a downregulation of the miR-196 family in endothelial cells upon hypoxia. Functionally, miR-196b-5p inhibited the angiogenic functions of endothelial cells in vitro and suppressed angiogenesis in Matrigel plugs and skin wound healing in vivo. Mechanistically, miR-196b-5p bound onto the 3' untranslated region (UTR) of high-mobility group AT-hook 2 (HMGA2) mRNA and repressed the translation of HMGA2, which in turn represses HIF1α accumulation in endothelial cells upon hypoxia. Together, our results establish the role of endothelial miR-196b-5p as an angiomiR that negatively regulates endothelial growth in angiogenesis via the hypoxia/miR-196b-5p/HMGA2/HIF1α loop. miR-196b-5p and its regulatory loop could be an important addition to the molecular mechanisms underlying angiogenesis and may serve as potential targets for antiangiogenic therapy.

MAIT cells and their implication in human oral diseases

OBJECTIVE

Mucosal-associated invariant T (MAIT) cells are unique innate-like T cells that are abundant in humans, accounting for 1-10% of circulating T cells and about 2% of total T cells in human oral cavity. MAIT cells can mount a strong immune response quickly without exogenous antigens and undergo a phenotypic transformation in the development of diseases. They produce cytokines involved in the Th1 and Th17 immune response and cytotoxic proteins, promote the dysfunction of autoreactive B cell and inhibit the function of NK cells. MAIT cells have been widely explored in autoimmune diseases, inflammatory diseases and tumors, and these mechanisms may also be involved in the pathogenesis of some oral diseases, while MAIT cells have not been systematically discussed in oral diseases.

METHODS

We searched PubMed/MEDLINE, EMBASE and Microsoft Bing databases to review and analyze relevant literatures on the impact of MAIT cells in the pathogenesis of human oral diseases.

CONCLUSION

Collected evidence elucidated the characteristics of MAIT cells and emphasized the potential roles of MAIT cells in oral lichen planus (OLP), chronic graft-versus-host disease (cGVHD), oral squamous cell carcinoma (OSCC), apical periodontitis (AP) and primary Sjogren's syndrome (pSS).

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.

CircARL8B Contributes to the Development of Breast Cancer Via Regulating miR-653-5p/HMGA2 Axis

Circular RNAs (circRNAs) act as essential regulators in breast cancer (BC) progression. In this paper, we aimed to investigate the functions of circARL8B in BC. The levels of circARL8B, ADP Ribosylation Factor Like GTPase 8B (ARL8B), miR-653-5p and high-mobility group AT-hook 2 (HMGA2) mRNA were examined by qRT-PCR. The stability of circARL8B was determined by RNase R assay and Actinomycin D assay. Cell viability and metastasis were evaluated by Cell Counting Kit-8 (CCK-8) assay and transwell assay, respectively. The levels of cellular phospholipids and triglycerides were measured using relevant kits. Protein levels were measured by western blot analysis. The association between miR-653-5p and circARL8B or HMGA2 was verified by dual-luciferase reporter assay. A murine xenograft model was established to explore the function of circARL8B in vivo. CircARL8B was increased in BC tissues and cells. CircARL8B silencing inhibited cell viability, migration, invasion and fatty acid metabolism in BC cells in vitro and blocked tumor growth in vivo. MiR-653-5p was identified as the target of circARL8B and miR-653-5p was negatively modulated by circARL8B. The suppressive role of circARL8B silencing in BC cell progression was abolished by miR-653-5p downregulation. Moreover, HMGA2 was the target gene of miR-653-5p. HMGA2 overexpression abrogated the effect of miR-653-5p on BC cell development. In addition, circARL8B knockdown might block PGE2/PI3K/AKT/GSK-3β/Wnt/β-catenin pathway. Silencing of circARL8B inhibited cell viability, migration, invasion and fatty acid metabolism via miR-653-5p/HMGA2 axis in BC.

LncRNA FENDRR in Carcinoma-Associated Fibroblasts Regulates the Angiogenesis of Oral Squamous Cell Carcinoma Through the PI3K/AKT Pathway

Angiogenesis is essential for the development of tumors. Studies have shown that carcinoma-associated fibroblasts (CAFs) are involved in regulating tumor angiogenesis, but the mechanism remains unclear. Recently, long noncoding RNAs (lncRNAs) have been proved to play an important role in the angiogenesis of various tumors. However, there is currently no research involving the regulation of CAFs on the angiogenesis of oral squamous cell carcinoma (OSCC) mediated by lncRNAs. By analyzing microarray data, we identified that the expression of lncRNA FOXF1 adjacent noncoding developmental regulatory RNA (FENDRR) in OSCC patients is downregulated, compared to that in normal tissues. Quantitative polymerase chain reaction (qPCR) results demonstrated that FENDRR expression is lower in CAFs compared to normal fibroblasts (NFs) of OSCC patients. KEGG pathway analysis revealed that some genes differentially expressed between CAFs and NFs of HNSCC patients are enriched to the PI3K/AKT pathway. Further experiments confirmed that the downregulation of FENDRR can activate the PI3K/AKT pathway in NFs and enhances the expression of matrix metalloproteinase 9 (MMP9). The overexpression of FENDRR had the opposite effect. Besides, we co-cultured human umbilical vein endothelial cells (HUVECs) with CAFs, and the tube-forming ability of HUVECs co-cultured with CAFs overexpressing FENDRR decreased significantly. However, activation of the AKT pathway of CAFs overexpressing FENDRR can weaken the inhibitory effect of FENDRR on angiogenesis. In summary, our experiments are focused on the influence of lncRNAs in CAFs on OSCC angiogenesis for the first time and prove that FENDRR mediates CAFs’ regulation of OSCC angiogenesis through the PI3K/AKT pathway.

Metronomic Therapy in Oral Squamous Cell Carcinoma

Metronomic therapy is characterized by drug administration in a low-dose, repeated, and regular manner without prolonged drug-free interval. The two main anticancer mechanisms of metronomic therapy are antiangiogenesis and immunomodulation, which have been demonstrated in several delicate in vitro and in vivo experiments. In contrast to the traditional maximum tolerated dose (MTD) dosing of chemotherapy, metronomic therapy possesses comparative efficacy but greatlydecreases the incidence and severity of treatment side-effects. Clinical trials of metronomic anticancer treatment have revealed promising results in a variety cancer types and specific patient populations such as the elderly and pediatric malignancies. Oral cavity squamous cell carcinoma (OCSCC) is an important health issue in many areas around the world. Long-term survival is about 50% in locally advanced disease despite having high-intensity treatment combined surgery, radiotherapy, and chemotherapy. In this article, we review and summarize the essence of metronomic therapy and focus on its applications in OCSCC treatment.

HMGA2 as a Critical Regulator in Cancer Development

The high mobility group protein 2 (HMGA2) regulates gene expression by binding to AT-rich regions of DNA. Akin to other DNA architectural proteins, HMGA2 is highly expressed in embryonic stem cells during embryogenesis, while its expression is more limited at later stages of development and in adulthood. Importantly, HMGA2 is re-expressed in nearly all human malignancies, where it promotes tumorigenesis by multiple mechanisms. HMGA2 increases cancer cell proliferation by promoting cell cycle entry and inhibition of apoptosis. In addition, HMGA2 influences different DNA repair mechanisms and promotes epithelial-to-mesenchymal transition by activating signaling via the MAPK/ERK, TGFβ/Smad, PI3K/AKT/mTOR, NFkB, and STAT3 pathways. Moreover, HMGA2 supports a cancer stem cell phenotype and renders cancer cells resistant to chemotherapeutic agents. In this review, we discuss these oncogenic roles of HMGA2 in different types of cancers and propose that HMGA2 may be used for cancer diagnostic, prognostic, and therapeutic purposes.

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.

In vitro and in vivo synergistic anti-tumor effect of LIN28 inhibitor and metformin in oral squamous cell carcinoma

Cancer stem cell therapy is becoming a focal point for oral squamous cell carcinoma (OSCC). They can be regulated by tumor glucose metabolism, whereas the regulation is not fully investigated in OSCC. Herein, we studied the synergistic anti-tumor effect of a LIN28 inhibitor C1632 and hypoglycemic medication metformin in OSCC. In this study, OSCC cell lines SCC9 and CAL27 were treated with C1632 and metformin respectively or synergistically. First, western blotting was performed to detect the expression level of LIN28 and its downstream molecule HMGA2. Second, MTT assay was conducted to assess cell proliferation. Next, wound healing assay and transwell assay were applied to evaluate cell migration. Then, xenograft mouse experiment was done to explore anti-tumor effect in vivo. Finally, western blotting was used to investigate the pharmacological mechanisms of the synergistic effect oft he two medication. Results showed that LIN28 and HMGA2 expression decreased significantly in SCC9 and CAL27 cells under 240 μM C1632 treatment for 72 h. These effects were synergized under combined treatment for 24 h. Cell proliferation ability and migration ability of both cell lines decreased significantly under respective and combined treatment. In xenograft mouse experiment, tumor weights decreased by 48% under 40 mg/kg/3d C1632 treatment, 53% under 250 mg/kg/d metformin treatment and 91% under combined treatment for 18 days. Tumor volumes decreased by 32%, 57% and 47% under C1632, metformin and combined treatment respectively. These results indicated that C1632 and metformin exerts synergistic anti-tumor effects in OSCC cell lines SCC9 and CAL27, and also inhibits xenograft tumor growth in vivo.

Significance of HMGA2 expression as independent poor prognostic marker in perihilar and distal cholangiocarcinoma resected with curative intent

BACKGROUND

Extrahepatic cholangiocarcinoma requires invasive surgery and is associated with poor prognosis; thus, a prognostic biomarker is highly needed. Extrahepatic cholangiocarcinoma is sub-classified into two types based on their location, namely perihilar and distal. Perihilar cholangiocarcinoma requires lobectomy as curative surgical resection, whereas the distal requires pancreatoduodenectomy. HMGA2 overexpression is reported to correlate with progression, aggressiveness, dissemination and poor prognosis in several types of cancers. Although its association with extrahepatic cholangiocarcinoma has been reported, none of the previous studies assessed its significance in each subtype.

METHODS

We assessed the expression of HMGA2 protein in surgical specimens after curative intent surgery in 80 patients including 41 with perihilar cholangiocarcinoma and 39 with distal cholangiocarcinoma by immunohistochemistry. We then examined its association with clinicopathological findings and patient survival outcomes.

RESULTS

We found that HMGA2 was expressed in 51% (21 of 41) of perihilar cholangiocarcinoma and 41% (16 of 39) of distal cholangiocarcinoma samples. In perihilar cholangiocarcinoma, we found significant correlations between expression and vascular invasion and perineural invasion. In distal cholangiocarcinoma, we found that protein levels correlated with tumor grade. Univariate and multivariate analyses demonstrated that HMGA2 expression was an independent poor prognostic factor for patients with both subtypes of disease.

CONCLUSIONS

Our results revealed that HMGA2 expression as an independent prognostic marker for both perihilar and distal cholangiocarcinoma that were resected with curative intent.

HMGA2-mediated tumorigenesis through angiogenesis in leiomyoma

OBJECTIVE

To study the role of HMGA2 in promoting angiogenesis in uterine leiomyoma (LM).

DESIGN

This study involved evaluation of vessel density and angiogenic factors in leiomyomas with HMGA2 overexpression; examining angiogenic factor expression and AKT signaling in myometrial (MM) and leiomyoma cells by introducing HMGA2 overexpression in vitro; and exploring vessel formation induced by HMGA2 overexpression both in vitro and in vivo.

SETTING

University research laboratory.

PATIENTS

None.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

The main outcome measures include vessel density in leiomyomas with HMGA2 (HMGA2-LM) or MED12 (MED12-LM) alteration; angiogenic factor expression in primary leiomyoma and in vitro cell line model; and vessel formation in leiomyoma cells with HMGA2 overexpression in vitro and in vivo.

RESULTS

Angiogenic factors and receptors were significantly upregulated at mRNA and protein levels in HMGA2-LM. Specifically, HMGA2-LM exhibited increased expression of VEGFA, EGF, bFGF, TGFα, VEGFR1, and VEGFR2 compared to MED12-LM and myometrium. Overexpression of HMGA2 in MM and LM cell lines resulted in increased secretion of angiogenesis-associated factors. Secreted factors promoted human umbilical vein endothelial cell (HUVEC) migration, tube formation, and wound healing. HMGA2 overexpression upregulated IGF2BP2 and pAKT, and silencing the IGF2BP2 gene reduced pAKT levels and reduced HUVEC migration. Myometrial cells with stable HMGA2 overexpression exhibited increased colony formation and cell growth in vitro and formed xenografts with increased blood vessels.

CONCLUSIONS

HMGA2-LM have a high vasculature density, which likely contributes to tumor growth and disease burden of this leiomyoma subtype. HMGA2 plays an important role in angiogenesis and the involvement of IGF2BP2-mediated pAKT activity in angiogenesis, which provides a potential novel target for therapy for this subtype of LM.

Neutrophils: Accomplices in metastasis

Metastasis is a critical cause of treatment failure and death in patients with advanced malignancies. Tumor cells can leave the primary site and enter the bloodstream; these circulating tumor cells then colonize target organs by overcoming blood shear stress, evading immune surveillance, and silencing the offensive capabilities of immune cells, eventually forming metastatic foci. From leaving the primary focus to the completion of distant metastasis, malignant tumor cells are supported and/or antagonized by certain immune cells. In particular, it has been found that myeloid granulocytes play an important role in this process. This review therefore aims to comprehensively describe the significance of neutrophils in solid tumor metastasis in terms of their supporting role in initiating the invasion and migration of tumor cells and assisting the colonization of circulating tumor cells in distant target organs, with the hope of providing insight into and ideas for anti-tumor metastasis treatment of tumor patients.

Screening and functional prediction of differentially expressed circRNAs in proliferative human aortic smooth muscle cells

Vascular smooth muscle cell (VSMC) proliferation is the pathological base of vascular remodelling diseases. Circular RNAs (circRNAs) are important regulators involved in various biological processes. However, the function of circRNAs in VSMC proliferation regulation remains largely unknown. This study was conducted to identify the key differentially expressed circRNAs (DEcircRNAs) and predict their functions in human aortic smooth muscle cell (HASMC) proliferation. To achieve this, DEcircRNAs between proliferative and quiescent HASMCs were detected using a microarray, followed by quantitative real-time RT-PCR validation. A DEcircRNA-miRNA-DEmRNA network was constructed, and functional annotation was performed using Gene Ontology (GO) and KEGG pathway analysis. The function of hsa_circ_0002579 in HASMC proliferation was analysed by Western blot. The functional annotation of the DEcircRNA-miRNA-DEmRNA network indicated that the four DEcircRNAs might play roles in the TGF-β receptor signalling pathway, Ras signalling pathway, AMPK signalling pathway and Wnt signalling pathway. Twenty-seven DEcircRNAs with coding potential were screened. Hsa_circ_0002579 might be a pro-proliferation factor of HASMC. Overall, our study identified the key DEcircRNAs between proliferative and quiescent HASMCs, which might provide new important clues for exploring the functions of circRNAs in vascular remodelling diseases.

HMGA Genes and Proteins in Development and Evolution

HMGA (high mobility group A) (HMGA1 and HMGA2) are small non-histone proteins that can bind DNA and modify chromatin state, thus modulating the accessibility of regulatory factors to the DNA and contributing to the overall panorama of gene expression tuning. In general, they are abundantly expressed during embryogenesis, but are downregulated in the adult differentiated tissues. In the present review, we summarize some aspects of their role during development, also dealing with relevant studies that have shed light on their functioning in cell biology and with emerging possible involvement of HMGA1 and HMGA2 in evolutionary biology.

Gene Expression Signature-Based Approach Identifies Antifungal Drug Ciclopirox As a Novel Inhibitor of HMGA2 in Colorectal Cancer

Human high-mobility group A2 (HMGA2) encodes for a non-histone chromatin protein which influences a variety of biological processes, including the cell cycle process, apoptosis, the DNA damage repair process, and epithelial–mesenchymal transition. The accumulated evidence suggests that high expression of HMGA2 is related to tumor progression, poor prognosis, and a poor response to therapy. Thus, HMGA2 is an important molecular target for many types of malignancies. Our recent studies revealed the positive connections between heat shock protein 90 (Hsp90) and HMGA2 and that the Hsp90 inhibitor has therapeutic potential to inhibit HMGA2-triggered tumorigenesis. However, 43% of patients suffered visual disturbances in a phase I trial of the second-generation Hsp90 inhibitor, NVP-AUY922. To identify a specific inhibitor to target HMGA2, the Gene Expression Omnibus (GEO) database and the Library of Integrated Network-based Cellular Signatures (LINCS) L1000platform were both analyzed. We identified the approved small-molecule antifungal agent ciclopirox (CPX) as a novel potential inhibitor of HMGA2. In addition, CPX induces cytotoxicity of colorectal cancer (CRC) cells by induction of cell cycle arrest and apoptosis in vitro and in vivo through direct interaction with the AT-hook motif (a small DNA-binding protein motif) of HMGA2. In conclusion, this study is the first to report that CPX is a novel potential inhibitor of HMGA2 using a drug-repurposing approach, which can provide a potential therapeutic intervention in CRC patients.