MiR-2392 suppresses metastasis and epithelial-mesenchymal transition by targeting MAML3 and WHSC1 in gastric cancer

High-yield extracellular vesicle production from HEK293T cells encapsulated in 3D auxetic scaffolds with cyclic mechanical stimulation for effective drug carrier systems

Extracellular vesicles (EVs) show promise in drug loading and delivery for medical applications. However, the lack of scalable manufacturing processes hinders the generation of clinically suitable quantities, thereby impeding the translation of EV-based therapies. Current EV production relies heavily on non-physiological two-dimensional (2D) cell culture or bioreactors, requiring significant resources. Additionally, EV-derived ribonucleic acid cargo in three-dimensional (3D) and 2D culture environments remains largely unknown. In this study, we optimized the biofabrication of 3D auxetic scaffolds encapsulated with human embryonic kidney 293 T (HEK293 T) cells, focusing on enhancing the mechanical properties of the scaffolds to significantly boost EV production through tensile stimulation in bioreactors. The proposed platform increased EV yields approximately 115-fold compared to conventional 2D culture, possessing properties that inhibit tumor progression. Further mechanistic examinations revealed that this effect was mediated by the mechanosensitivity of YAP/TAZ. EVs derived from tensile-stimulated HEK293 T cells on 3D auxetic scaffolds demonstrated superior capability for loading doxorubicin compared to their 2D counterparts for cancer therapy. Our results underscore the potential of this strategy for scaling up EV production and optimizing functional performance for clinical translation.

MAML3-fusions modulate vascular and immune tumour microenvironment and confer high metastatic risk in pheochromocytoma and paraganglioma

Pheochromocytomas and paragangliomas are rare neuroendocrine tumours. Around 20-25 % of patients develop metastases, for which there is an urgent need of prognostic markers and therapeutic stratification strategies. The presence of a MAML3-fusion is associated with increased metastatic risk, but neither the processes underlying disease progression, nor targetable vulnerabilities have been addressed. We have compiled a cohort of 850 patients, which has shown a 3.65 % fusion prevalence and represents the largest MAML3-positive series reported to date. While MAML3-fusions mainly cause single pheochromocytomas, we also observed somatic post-zygotic events, resulting in multiple tumours in the same patient. MAML3-tumours show increased expression of neuroendocrine-to-mesenchymal transition markers, MYC-targets, and angiogenesis-related genes, leading to a distinct tumour microenvironment with unique vascular and immune profiles. Importantly, our findings have identified MAML3-tumours specific vulnerabilities beyond Wnt-pathway dysregulation, such as a rich vascular network, and overexpression of PD-L1 and CD40, suggesting potential therapeutic targets.

Tiam1 methylation by NSD2 promotes Rac1 signaling activation and colon cancer metastasis

Metastasis is a major cause of cancer therapy failure and mortality. However, targeting metastatic seeding and colonization remains a significant challenge. In this study, we identified NSD2, a histone methyltransferase responsible for dimethylating histone 3 at lysine 36, as being overexpressed in metastatic tumors. Our findings suggest that NSD2 overexpression enhances tumor metastasis both in vitro and in vivo. Further analysis revealed that NSD2 promotes tumor metastasis by activating Rac1 signaling. Mechanistically, NSD2 combines with and activates Tiam1 (T lymphoma invasion and metastasis 1) and promotes Rac1 signaling by methylating Tiam1 at K724. In vivo and in vitro studies revealed that Tiam1 K724 methylation could be a predictive factor for cancer prognosis and a potential target for metastasis inhibition. Furthermore, we have developed inhibitory peptide which was proved to inhibit tumor metastasis through blocking the interaction between NSD2 and Tiam1. Our results demonstrate that NSD2-methylated Tiam1 promotes Rac1 signaling and cancer metastasis. These results provide insights into the inhibition of tumor metastasis.

miRNA/epithelial-mesenchymal axis (EMT) axis as a key player in cancer progression and metastasis: A focus on gastric and bladder cancers

The metastasis a major hallmark of tumors that its significant is not only related to the basic research, but clinical investigations have revealed that majority of cancer deaths are due to the metastasis. The metastasis of tumor cells is significantly increased due to EMT mechanism and therefore, inhibition of EMT can reduce biological behaviors of tumor cells and improve the survival rate of patients. One of the gaps related to cancer metastasis is lack of specific focus on the EMT regulation in certain types of tumor cells. The gastric and bladder cancers are considered as two main reasons of death among patients in clinical level. Herein, the role of EMT in regulation of their progression is evaluated with a focus on the function of miRNAs. The inhibition/induction of EMT in these cancers and their ability in modulation of EMT-related factors including ZEB1/2 proteins, TGF-β, Snail and cadherin proteins are discussed. Moreover, lncRNAs and circRNAs in crosstalk of miRNA/EMT regulation in these tumors are discussed and final impact on cancer metastasis and response of tumor cells to the chemotherapy is evaluated. Moreover, the impact of miRNAs transferred by exosomes in regulation of EMT in these cancers are discussed.

Positive effect of miR-2392 on fibroblast to cardiomyocyte-like cell fate transition: an in silico and in vitro study

INTRODUCTION

Somatic cell fate transition is now gained great importance in tissue regeneration. Currently, research is focused on heart tissue regeneration by reprogramming diverse cells into cardiomyocyte-like cells. Here, we examined the possible effect of miRNAs on the transdifferentiation of fibroblasts into cardiomyocyte-like cells.

METHODS

First heart-specific miRNAs were identified by comparing the gene expression profiles of heart tissue to other body tissues using bioinformatic techniques. After identifying heart-specific miRNAs, their cellular and molecular functions were studied using the miRWalk and miRBase databases. Then the candidate miRNA was cloned into a lentiviral vector. Following, human dermal fibroblasts were cultured and treated with compounds forskolin, valproic acid, and CHIR99021. After 24 h, the lentivector harboring miRNA gene was transfected into the cells to initiate the transdifferentiation process. Finally, after a two-week treatment period, the efficiency of transdifferentiation was examined by inspecting the appearance of the cells and measuring the expression levels of cardiac genes and proteins using RT-qPCR and immunocytochemistry techniques.

RESULTS

Nine miRNAs were identified with higher expression in the heart. The miR-2392 was nominated as the candidate miRNA due to its function and specific expression in the heart. This miRNA has a direct connection with genes involved in cell growth and differentiation; e.g., MAPK and Wnt signaling pathways. According to in vitro results cardiac genes and proteins demonstrated an increase in expression in the fibroblasts that simultaneously received the three chemicals and miR-2392.

CONCLUSION

Considering the ability of miR-2392 to induce the expression of cardiac genes and proteins in fibroblast cells, it can induce fibroblasts to differentiate into cardiomyocyte-like cells. Therefore, miR-2392 could be further optimized for cardiomyocyte regeneration, tissue repair, and drug design studies.

Functional screening of congenital heart disease risk loci identifies 5 genes essential for heart development in zebrafish

Congenital heart disease (CHD) is the most common birth defect worldwide and a main cause of perinatal and infant mortality. Our previous genome-wide association study identified 53 SNPs that associated with CHD in the Han Chinese population. Here, we performed functional screening of 27 orthologous genes in zebrafish using injection of antisense morpholino oligos. From this screen, 5 genes were identified as essential for heart development, including iqgap2, ptprt, ptpn22, tbck and maml3. Presumptive roles of the novel CHD-related genes include heart chamber formation (iqgap2 and ptprt) and atrioventricular canal formation (ptpn22 and tbck). While deficiency of maml3 led to defective cardiac trabeculation and consequent heart failure in zebrafish embryos. Furthermore, we found that maml3 mutants showed decreased cardiomyocyte proliferation which caused a reduction in cardiac trabeculae due to inhibition of Notch signaling. Together, our study identifies 5 novel CHD-related genes that are essential for heart development in zebrafish and first demonstrates that maml3 is required for Notch signaling in vivo.

Ceramide Metabolism Regulated by Sphingomyelin Synthase 2 Is Associated with Acquisition of Chemoresistance via Exosomes in Human Leukemia Cells

Ceramide levels controlled by the sphingomyelin (SM) cycle have essential roles in cancer cell fate through the regulation of cell proliferation, death, metastasis, and drug resistance. Recent studies suggest that exosomes confer cancer malignancy. However, the relationship between ceramide metabolism and exosome-mediated cancer malignancy is unclear. In this study, we elucidated the role of ceramide metabolism via the SM cycle in exosomes and drug resistance in human leukemia HL-60 and adriamycin-resistant HL-60/ADR cells. HL-60/ADR cells showed significantly increased exosome production and release compared with parental chemosensitive HL-60 cells. In HL-60/ADR cells, increased SM synthase (SMS) activity reduced ceramide levels, although released exosomes exhibited a high ceramide ratio in both HL-60- and HL-60/ADR-derived exosomes. Overexpression of SMS2 but not SMS1 suppressed intracellular ceramide levels and accelerated exosome production and release in HL-60 cells. Notably, HL-60/ADR exosomes conferred cell proliferation and doxorubicin resistance properties to HL-60 cells. Finally, microRNA analysis in HL-60 and HL-60/ADR cells and exosomes showed that miR-484 elevation in HL-60/ADR cells and exosomes was associated with exosome-mediated cell proliferation. This suggests that intracellular ceramide metabolism by SMS2 regulates exosome production and release, leading to acquisition of drug resistance and enhanced cell proliferation in leukemia cells.

The Role of MicroRNA in the Regulation of Tumor Epithelial–Mesenchymal Transition

Consistently, the high metastasis of cancer cells is the bottleneck in the process of tumor treatment. In this process of metastasis, a pivotal role is executed by epithelial–mesenchymal transition (EMT). The epithelial-to-mesenchymal transformation was first proposed to occur during embryonic development. Later, its important role in explaining embryonic developmental processes was widely reported. Recently, EMT and its intermediate state were also identified as crucial drivers in tumor progression with the gradual deepening of research. To gain insights into the potential mechanism, increasing attention has been focused on the EMT-related transcription factors. Correspondingly, miRNAs target transcription factors to control the EMT process of tumor cells in different types of cancers, while there are still many exciting and challenging questions about the phenomenon of microRNA regulation of cancer EMT. We describe the relevant mechanisms of miRNAs regulating EMT, and trace the regulatory roles and functions of major EMT-related transcription factors, including Snail, Twist, zinc finger E-box-binding homeobox (ZEB), and other families. In addition, on the basis of the complex regulatory network, we hope that the exploration of the regulatory relationship of non-transcription factors will provide a better understanding of EMT and cancer metastasis. The identification of the mechanism leading to the activation of EMT programs during diverse disease processes also provides a new protocol for the plasticity of distinct cellular phenotypes and possible therapeutic interventions. Here, we summarize the recent progress in this direction, with a promising path for further insight into this fast-moving field.

Deep sequencing unveils altered cardiac miRNome in congenital heart disease

Congenital heart disease (CHD) surges from fetal cardiac dysmorphogenesis and chiefly contributes to perinatal morbidity and cardiovascular disease mortality. A continual rise in prevalence and prerequisite postoperative disease management creates need for better understanding and new strategies to control the disease. The interaction between genetic and non-genetic factors roots the multifactorial status of this disease, which remains incompletely explored. The small non-coding microRNAs (miRs, miRNAs) regulate several biological processes via post-transcriptional regulation of gene expression. Abnormal expression of miRs in developing and adult heart is associated with anomalous cardiac cell differentiation, cardiac dysfunction, and cardiovascular diseases. Here, we attempt to discover the changes in cardiac miRNA transcriptome in CHD patients over those without CHD (non-CHD) and find its role in CHD through functional annotation. This study explores the miRNome in three most commonly occurring CHD subtypes, namely atrial septal defect (ASD), ventricular septal defect (VSD), and tetralogy of fallot (TOF). We found 295 dysregulated miRNAs through high-throughput sequencing of the cardiac tissues. The bioinformatically predicted targets of these differentially expressed miRs were functionally annotated to know they were entailed in cell signal regulatory pathways, profoundly responsible for cell proliferation, survival, angiogenesis, migration and cell cycle regulation. Selective miRs (hsa-miR-221-3p, hsa-miR-218-5p, hsa-miR-873-5p) whose expression was validated by qRT-PCR, have been reported for cardiogenesis, cardiomyocyte proliferation, cardioprotection and cardiac dysfunction. These results indicate that the altered miRNome to be responsible for the disease status in CHD patients. Our data expand the existing knowledge on the epigenetic changes in CHD. In future, characterization of these cardiac-specific miRs will add huge potential to understand cardiac development, function, and molecular pathogenesis of heart diseases with a prospect of epigenetic manipulation for cardiac repair.

Poria Acid, Triterpenoids Extracted from Poria cocos, Inhibits the Invasion and Metastasis of Gastric Cancer Cells

Background: Poria cocos (P. cocos) is an important medicinal fungus in traditional Chinese medicine. Poria acid (PA), a triterpenoid compound, is an effective component of traditional Chinese medicine P. cocos. This experiment investigated the anti-gastric cancer biological activity of PA in vitro. Methods: The effect of PA on the viability of gastric cancer cells was detected by the thiazolyl blue (MTT) assay. Cell adhesion assays were used to detect changes in the adhesion of cells treated after PA (0, 20, 40, and 80 µmol/L). The ability of cell invasion and migration were detected by Transwell assays and wound healing assays. A high-content imaging system was used to dynamically record the motility of the gastric cancer cells after PA (0, 20, 40, and 80 µmol/L) treatment. Western blotting was used to detect the expression of epithelial–mesenchymal transformation (EMT), invasion and migration related proteins. Results: The MTT assay showed that the proliferation of gastric cancer cells was significantly inhibited after PA treatment. Cell adhesion experiments showed that the adhesion of gastric cancer cells was significantly decreased after PA treatment. Compared with the control group, the wound healing area of the gastric cancer cells treated with different concentrations of PA decreased. The Transwell assay showed that the number of gastric cancer cells passing through the cell membrane were significantly reduced after PA treatment. In addition, after PA treatment, the cells’ movement distance and average movement speed were significantly lower than those of the control group. Finally, PA can significantly alter the expression of EMT-related proteins E-cadherin, N-cadherin, and Vimentin and decreased the expressions of metastasis-related proteins matrix metalloproteinase (MMP) 2, MMP-9 and tissue inhibition of matrix metalloproteinase (TIMP)1 in the gastric cancer cells. Conclusions: Triterpenoids from P. cocos have significant biological activity against gastric cancer, and the mechanism may be involved in the process of epithelial–mesenchymal transformation.

Exosomal miRNA profiles of triple-negative breast cancer in neoadjuvant treatment

Triple-negative breast cancer (TNBC) is characterized by aggressive clinicopathological features and is associated with a poor prognosis. Identifying patients that are non-responsive to chemotherapy remains a critical goal for effective personalized therapies. In the present study, the predictive value of exosomal microRNAs (miRNAs) was investigated in patients with TNBC. Exosomes were isolated from patients with TNBC undergoing neoadjuvant chemotherapy. Microarray-based miRNA profiles were compared between patients with pathological complete response (pCR; n=12) and non-pCR (n=12). Furthermore, the miRNA profiles of non-pCR patients with breast cancer recurrence were compared with those with no recurrence. A total of 16 differentially expressed exosomal miRNAs were identified between the patients with pCR and non-pCR by microarray analysis. Of these, a combined signature of four miRNAs (miR-4448, miR-2392, miR-2467-3p and miR-4800-3p) could be used to discriminate between pCR and non-pCR patients with TNBC with an area under the curve value of 0.7652. Furthermore, this study found 43 differentially expressed miRNAs between the patients with non-pCR and recurrence and non-pCR patients without recurrence. In network analysis, 'pathway in cancer', 'focal adhesion' and 'cell cycle' were identified as the crucial pathways in patients with non-pCR who also developed recurrence. Several exosomal miRNAs may be useful biomarkers to predict treatment efficacy for TNBC. The present study identified patients who were resistant to standard chemotherapy and therefore more likely to develop breast cancer recurrence.

Role of miR-2392 in driving SARS-CoV-2 infection

MicroRNAs (miRNAs) are small non-coding RNAs involved in post-transcriptional gene regulation that have a major impact on many diseases and provide an exciting avenue toward antiviral therapeutics. From patient transcriptomic data, we determined that a circulating miRNA, miR-2392, is directly involved with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) machinery during host infection. Specifically, we show that miR-2392 is key in driving downstream suppression of mitochondrial gene expression, increasing inflammation, glycolysis, and hypoxia, as well as promoting many symptoms associated with coronavirus disease 2019 (COVID-19) infection. We demonstrate that miR-2392 is present in the blood and urine of patients positive for COVID-19 but is not present in patients negative for COVID-19. These findings indicate the potential for developing a minimally invasive COVID-19 detection method. Lastly, using in vitro human and in vivo hamster models, we design a miRNA-based antiviral therapeutic that targets miR-2392, significantly reduces SARS-CoV-2 viability in hamsters, and may potentially inhibit a COVID-19 disease state in humans.

The Great Deceiver: miR-2392's Hidden Role in Driving SARS-CoV-2 Infection

MicroRNAs (miRNAs) are small non-coding RNAs involved in post-transcriptional gene regulation that have a major impact on many diseases and provides an exciting avenue towards antiviral therapeutics. From patient transcriptomic data, we have discovered a circulating miRNA, miR-2392, that is directly involved with SARS-CoV-2 machinery during host infection. Specifically, we show that miR-2392 is key in driving downstream suppression of mitochondrial gene expression, increasing inflammation, glycolysis, and hypoxia as well as promoting many symptoms associated with COVID-19 infection. We demonstrate miR-2392 is present in the blood and urine of COVID-19 positive patients, but not detected in COVID-19 negative patients. These findings indicate the potential for developing a novel, minimally invasive, COVID-19 detection method. Lastly, using in vitro human and in vivo hamster models, we have developed a novel miRNA-based antiviral therapeutic that targets miR-2392, significantly reduces SARS-CoV-2 viability in hamsters and may potentially inhibit a COVID-19 disease state in humans.

MicroRNAs in Cancer: From Gene Expression Regulation to the Metastatic Niche Reprogramming

By 2003, the Human Genome project had been completed; however, it turned out that 97% of genome sequences did not encode proteins. The explanation came later when it was found the untranslated DNA contain sequences for short microRNAs (miRNAs) and long noncoding RNAs that did not produce any mRNAs or tRNAs, but instead were involved in the regulation of gene expression. Initially identified in the cytoplasm, miRNAs have been found in all cell compartments, where their functions are not limited to the degradation of target mRNAs. miRNAs that are secreted into the extracellular space as components of exosomes or as complexes with proteins, participate in morphogenesis, regeneration, oncogenesis, metastasis, and chemoresistance of tumor cells. miRNAs play a dual role in oncogenesis: on one hand, they act as oncogene suppressors; on the other hand, they function as oncogenes themselves and inactivate oncosuppressors, stimulate tumor neoangiogenesis, and mediate immunosuppressive processes in the tumors, The review presents current concepts of the miRNA biogenesis and their functions in the cytoplasm and nucleus with special focus on the noncanonical mechanisms of gene regulation by miRNAs and involvement of miRNAs in oncogenesis, as well as the authors' opinion on the role of miRNAs in metastasis and formation of the premetastatic niche.

Mastermind Like Transcriptional Coactivator 3 (MAML3) Drives Neuroendocrine Tumor Progression

Metastatic disease in pheochromocytomas and paragangliomas (PCC/PGL) is not well-understood. The Cancer Genome Atlas discovered recurrent MAML3 fusion genes in a subset of tumors that lacked known germline or somatic driver mutations and were associated with aggressive disease. Here, we aimed to investigate the role of MAML3 in tumorigenesis. Human PCC/PGLs were used for IHC and genetic analysis. Three neuroendocrine tumor cell lines, SK-N-SH, QGP-1, and BON-1, were transiently transfected with MAML3 (FL) or exon 1 deleted MAML3 (dEx1; mimicking the fusion), and biologic effects of overexpression were examined in vitro. We found 7% (4/55) of human PCC/PGL have UBTF∼MAML3 fusions and all were sporadic cases with metastatic disease. Fusion-positive tumors had intense MAML3 nuclear staining and increased β-catenin by IHC and showed increased WNT4 expression. In vitro, overexpression of FL and dEx1 MAML3 increased invasion in SK-N-SH, QGP-1, and BON-1 (all P < 0.05) and increased soft-agar colony formation in QGP-1 and BON-1 (all P < 0.05). Cotransfection with FL or dEx1 MAML3 and β-catenin increased TCF/LEF promoter activation by luciferase activity and coimmunoprecipitation confirmed interaction between MAML3 and β-catenin. These data suggest MAML3 is involved in WNT signaling pathway activation. In summary, UBTF∼MAML3 fusions are present in a subset of PCC/PGL and associated with metastatic disease without other known drivers. MAML3 overexpression led to increased tumorigenicity in neuroendocrine tumor cells and the mechanism of action may involve WNT signaling pathways. IMPLICATIONS: MAML3 increases tumorigenicity and invasion in neuroendocrine tumor cells and may be a prognostic marker for aggressive disease.

BTXA regulates the epithelial-mesenchymal transition and autophagy of keloid fibroblasts via modulating miR-1587/miR-2392 targeted ZEB2

Keloids are very resistant to treatment in dermatology and plastic surgical practice. The present study aimed to explore the underlying mechanism of botulinum toxin A (BTXA) treated human skin keloid fibroblasts (HSFBs) proving some new insights into keloids treatment. Expression of miR-1587 and miR-2392 were significantly down-regulated in keloid tissues and HSFBs, while the ZEB2 was a target of both and up-regulated in keloid tissues and HSFBs compared with the normal controls. BTXA could significantly increase the expression of miR-1587 and miR-2392 but decrease the expression of ZEB2. BTXA could significantly inhibit the proliferation, cell cycle, and migration and promote apoptosis and autophagy of HSFBs; however, miR-1587 and miR-2392 inhibitors could reverse these effects of BTXA on HSFBs. Silencing ZEB2 could significantly attenuate the effects of miR-1587 and miR-2392 inhibitors in promoting cell proliferation and migration and suppressing apoptosis and autophagy of HSFBs after treating with BTXA. BTXA could suppress the proliferation and migration and promote apoptosis and autophagy of HSFBs via modulating miR-1587/miR-2392 targeted ZEB2.

Targeting epigenetic regulators for cancer therapy: mechanisms and advances in clinical trials

Epigenetic alternations concern heritable yet reversible changes in histone or DNA modifications that regulate gene activity beyond the underlying sequence. Epigenetic dysregulation is often linked to human disease, notably cancer. With the development of various drugs targeting epigenetic regulators, epigenetic-targeted therapy has been applied in the treatment of hematological malignancies and has exhibited viable therapeutic potential for solid tumors in preclinical and clinical trials. In this review, we summarize the aberrant functions of enzymes in DNA methylation, histone acetylation and histone methylation during tumor progression and highlight the development of inhibitors of or drugs targeted at epigenetic enzymes.

Polymorphisms and genetic effects of PRLR, MOGAT1, MINPP1 and CHUK genes on milk fatty acid traits in Chinese Holstein

BACKGROUND

Our initial genome-wide association study (GWAS) identified 20 promising candidate genes for milk fatty acid (FA) traits in a Chinese Holstein population, including PRLR, MOGAT1, MINPP1 and CHUK genes. In this study, we performed whether they had significant genetic effects on milk FA traits in Chinese Holstein.

RESULTS

We re-sequenced the entire exons and 3000 bp of the 5' and 3' flanking regions, and identified 11 single nucleotide polymorphisms (SNPs), containing four in PRLR, two in MOGAT1, two in MINPP1, and three in CHUK. The SNP-based association analyses showed that all the 11 SNPs were significantly associated with at least one milk FA trait (P = 0.0456 ~ < 0.0001), and none of them had association with C11:0, C13:0, C15:0 and C16:0 (P > 0.05). By the linkage disequilibrium (LD) analyses, we found two, one, one, and one haplotype blocks in PRLR, MOGAT1, MINPP1, and CHUK, respectively, and each haplotype block was significantly associated with at least one milk FA trait (P = 0.0456 ~ < 0.0001). Further, g.38949011G > A in PRLR, and g.111599360A > G and g.111601747 T > A in MOGAT1 were predicted to alter the transcription factor binding sites (TFBSs). A missense mutation, g.39115344G > A, could change the PRLR protein structure. The g.20966385C > G of CHUK varied the binding sequences for microRNAs. Therefore, we deduced the five SNPs as the potential functional mutations.

CONCLUSION

In summary, we first detected the genetic effects of PRLR, MOGAT1, MINPP1 and CHUK genes on milk FA traits, and researched the potential functional mutations. These data provided the basis for further investigation on function validation of the four genes in Chinese Holstein.

Whole-exome sequencing of familial esophageal squamous cell carcinoma identified rare pathogenic variants in new predisposition genes

PURPOSE

Esophageal squamous cell carcinoma (ESCC) is one of the most important causes of mortality in the developing world. Although hereditary forms arise from germ-line mutations in TP53, Rb, and the mismatch repair genes, many familial cases present with an unknown inherited cause. The new theory of rare, high-penetrance mutations in less known genes is a likely explanation for the underlying predisposition in some of these familial cases.

METHODS

Exome sequencing was performed in 9 patients with esophageal squamous cancer from 9 families with strong disease aggregation without mutations in known hereditary esophageal cancer genes. Data analysis was limited to only really rare variants (0-0.01%), producing a putative loss of function and located in genes with a role compatible with carcinogenesis.

RESULTS

Twenty-two final candidate variants were selected and validated by Sanger sequencing. Correct family segregation and somatic studies were used to categorize the most interesting variants in CDK11A, ARID1A, JMJD6, MAML3, CDKN2AIP, and PHLDA1.

CONCLUSION

Together, we identified new potential esophageal squamous cancer predisposition variants in genes which may have a role in cancer and are involved in chromatin remodeling and cell-cycle pathway, which could increase the risk of ESCC.

Non-coding RNAs in regulating gastric cancer metastasis

Gastric cancer is one of the leading causes of cancer-related deaths worldwide, and mortality remains high, especially in East Asia. At present, the main method to diagnose gastric cancer is pathological biopsy. At the time of diagnosis, most patients have been diagnosed with advanced cancer and metastasis. The treatment of gastric cancer patients is mainly radical surgical resection and chemoradiotherapy, while patients with metastatic tumor have great challenges to radical surgery and are prone to drug resistance. Metastasis is an important factor affecting tumor development. In addition, evidence accumulated in the literature indicates that non-coding RNA plays a key role in tumor metastasis. This article reviews the role of ncRNAs in gastric cancer metastasis and discusses the regulatory mechanism in the development and treatment of gastric cancer.

LncRNA CACNA1G-AS1 facilitates hepatocellular carcinoma progression through the miR-2392/C1orf61 pathway

Emerging studies have indicated that long noncoding RNAs (lncRNAs) possess various functions in initiating human cancers. However, the role of lncRNAs in hepatocellular carcinoma (HCC) still remains ill understood. In this study, we sought to investigate the role of lncRNA CACNA1G-AS1 in HCC progression. Through bioinformatics analysis, we found that CACNA1G-AS1 expression was significantly upregulated in HCC tissues compared with that in the adjacent normal tissues. Moreover, CACNA1G-AS1 upregulation indicated poor prognosis in HCC patients. Knockdown of CACNA1G-AS1 attenuated the proliferation, migration, and invasion of HCC cells. Additionally, decreased expression of CACNA1G-AS1 prevented epithelial-mesenchymal transition. In vivo assay also showed that CACNA1G-AS1 silencing HCC cells have smaller tumor volumes and weights. Further investigations demonstrated that CACNA1G-AS1 worked as a competing endogenous RNA to bind microRNA-2392 (miR-2392) and thereby alleviate the repression of the downstream target C1orf61. Collectively, CACNA1G-AS1 promotes HCC progression through regulating the miR-2392/C1orf61 pathway.

Knockdown of NSD2 Suppresses Renal Cell Carcinoma Metastasis by Inhibiting Epithelial-Mesenchymal Transition

Background: Renal cell carcinoma (RCC) accounts for around 85% of all primary kidney neoplasms, which is one of top 10 common cancers worldwide. Nuclear receptor suppressor of variegation, enhancer of zeste, and trithorax (SET) domain-containing 2 (NSD2), belonging to NSD protein family, functions as an oncogene in the pathogenesis of multiple cancers. Methods: GEO database was used to analyze the expression of NSD2 mRNA in renal cancer. Furthermore, NSD2 protein level in clear cell RCC (ccRCC) tissues was detected by immunohistochemistry (IHC). Knockdown efficiency of different siRNAs was evaluated by quantitative real-time PCR (qRT-PCR) and western blot analysis. The biological role and molecular mechanism of NSD2 in RCC metastasis were investigated via a series of functional experiments. Results: NSD2 mRNA was massively amplified in several types of renal cancer, especially in metastatic ccRCC. The expression level of NSD2 protein was elevated in ccRCC tissues, but not correlated with pathological grading. The migratory and invasive properties were significantly repressed in NSD2-silenced RCC cells, concurrent with an increase of E-cadherin expression and a decrease of N-cadherin and Vimentin expression. Conclusion: Down-regulation of NSD2 could potently suppress cell migration and invasion through inhibiting epithelial-mesenchymal transition (EMT), indicating that NSD2 may be a potential therapeutic target for metastatic RCC.

Upregulation of lncRNA ADAMTS9-AS2 Promotes Salivary Adenoid Cystic Carcinoma Metastasis via PI3K/Akt and MEK/Erk Signaling

Neurotropic infiltrative growth and distant metastasis are the main causes of death in salivary adenoid cystic carcinoma (SACC) patients. Long noncoding RNAs (lncRNAs) are involved in many human neoplasms, however, their potential roles in SACC are unclear. In our study, we found that ADAM metallopeptidase with thrombospondin type 1 motif, 9 (ADAMTS9) antisense RNA 2 (ADAMTS9-AS2) was significantly upregulated in SACC patients with metastasis and SACC-lung metastasis (LM) cells. Moreover, ADAMTS9-AS2 expression was closely associated with the prognosis and distant metastasis in SACC patients. Next, we found that c-myc could specifically bind to the promoter of ADAMTS9-AS2 and activated its transcription. Knockdown of ADAMTS9-AS2 significantly inhibited migration and invasion of SACC cells in vitro and distant lung metastasis in vivo. Furthermore, ADAMTS9-AS2, which mainly expressed in the cytoplasm, shared microRNA (miRNA) response elements with Integrin α6 (ITGA6). Overexpression of ADAMTS9-AS2 competitively bound to miR-143-3p that inhibited ITGA6 from miRNA-mediated degradation, and thus it activated the activity of PI3K/Akt and MEK/Erk signaling and facilitated SACC metastasis. In summary, ADAMTS9-AS2 promotes migration and invasion in SACC by competing with miR-143-3p. This sheds a new insight into the regulation mechanism of ADAMTS9-AS2, and it provides a possible application for the SACC treatment.

Molecular alterations of cancer cell and tumour microenvironment in metastatic gastric cancer

The term metastasis is widely used to describe the endpoint of the process by which tumour cells spread from the primary location to an anatomically distant site. Achieving successful dissemination is dependent not only on the molecular alterations of the cancer cells themselves, but also on the microenvironment through which they encounter. Here, we reviewed the molecular alterations of metastatic gastric cancer (GC) as it reflects a large proportion of GC patients currently seen in clinic. We hope that further exploration and understanding of the multistep metastatic cascade will yield novel therapeutic targets that will lead to better patient outcomes.

Relationship between NSD2 and tumors

Nuclear receptor binding SET domain-protein 2 (NSD2), also known as MMSET or WHSC1, is a member of the NSD family. Methylation of histone as an important regulatory mechanism in epigenetics plays an important role in transcriptional regulation and chromatin remodeling. The overexpression of NSD2, caused by t(4; 14) (p16; q23) translocation, is closely related to the prognosis of patients with multiple myeloma. In addition, high expression of NSD2 can be detected in many other malignant tumors. NSD2 catalyzes the methylation of the lysine sites of histone, and promotes the initiation and progression of tumors by participating in the interaction among multiple proteins or the regulation of target genes. NSD2 and related signal molecules are expected to be the targets for treatment of various related tumors. Elucidating the mechanism of NSD2 may promote the development of targeted drugs and provide new solutions for the treatment of various NSD2-related tumors.

Thymoquinone Inhibits the Migration and Invasive Characteristics of Cervical Cancer Cells SiHa and CaSki In Vitro by Targeting Epithelial to Mesenchymal Transition Associated Transcription Factors Twist1 and Zeb1

Cervical cancer is one of the most common gynecological malignant tumors worldwide, for which chemotherapeutic strategies are limited due to their non-specific cytotoxicity and drug resistance. The natural product thymoquinone (TQ) has been reported to target a vast number of signaling pathways in carcinogenesis in different cancers, and hence is regarded as a promising anticancer molecule. Inhibition of epithelial to mesenchymal transition (EMT) regulators is an important approach in anticancer research. In this study, TQ was used to treat the cervical cancer cell lines SiHa and CaSki to investigate its effects on EMT-regulatory proteins and cancer metastasis. Our results showed that TQ has time-dependent and dose-dependent cytotoxic effects, and it also inhibits the migration and invasion processes in different cervical cancer cells. At the molecular level, TQ treatment inhibited the expression of Twist1, Zeb1 expression, and increased E-Cadherin expression. Luciferase reporter assay showed that TQ decreases the Twist1 and Zeb1 promoter activities respectively, indicating that Twist1 and Zeb1 might be the direct target of TQ. TQ also increased cellular apoptosis in some extent, but apoptotic genes/proteins we tested were not significant affected. We conclude that TQ inhibits the migration and invasion of cervical cancer cells, probably via Twist1/E-Cadherin/EMT or/and Zeb1/E-Cadherin/EMT, among other signaling pathways.