MicroRNA-30e Functions as a Tumor Suppressor in Cervical Carcinoma Cells through Targeting GALNT7

Comprehensive pan-cancer analysis reveals the versatile role of GALNT7 in epigenetic alterations and immune modulation in cancer

Cancer is a leading cause of mortality globally, characterized by intricate molecular alterations, including epigenetic changes such as glycosylation. This study presents a comprehensive pan-cancer analysis of Polypeptide N-Acetylgalactosaminyltransferase 7 (GALNT7), an enzyme involved in mucin-type O-linked protein glycosylation. GALNT7 has previously been linked to various cancers, but a unified analysis across cancer types is lacking. Leveraging data from TCGA, GTEx, and other sources, we scrutinized GALNT7's expression, prognostic relevance, links to immune-related genes, immune cell infiltration, and its involvement in tumor genetic heterogeneity across 33 cancer types. GALNT7 exhibited diverse expression patterns across cancer types, showcasing its potential as an oncogenic factor, with its expression levels linked to both positive and negative prognoses, highlighting the context-specific nature of its role in cancer progression. We delved into the intricate interplay between GALNT7 and immune genes, unveiling positive and negative correlations, underscoring complex interactions in the tumor microenvironment. GALNT7 was found to impact immune cell infiltration, which could have implications for treatment strategies. Additionally, GALNT7 displayed associations with genetic tumor aspects, encompassing genomic instability, DNA repair issues, and genetic mutations, hinting at its pivotal role in shaping the genetic landscape of diverse cancers. Enrichment analysis uncovered potential functions of GALNT7 beyond glycosylation, such as its participation in signaling pathways and its association with various diseases, notably cancer. This comprehensive analysis elucidates the multifaceted role of GALNT7 in cancer biology, underlining its potential as a therapeutic target and biomarker across various cancer types. These findings provide valuable insights for future research and the development of personalized cancer treatment strategies.

MiR-662 is associated with metastatic relapse in early-stage breast cancer and promotes metastasis by stimulating cancer cell stemness

BACKGROUND

Breast cancer (BC) metastasis, which often occurs in bone, contributes substantially to mortality. MicroRNAs play a fundamental role in BC metastasis, although microRNA-regulated mechanisms driving metastasis progression remain poorly understood.

METHODS

MiRome analysis in serum from BC patients was performed by TaqMan™ low-density array. MiR-662 was overexpressed following MIMIC-transfection or lentivirus transduction. Animal models were used to investigate the role of miR-662 in BC (bone) metastasis. The effect of miR-662-overexpressing BC cell conditioned medium on osteoclastogenesis was investigated. ALDEFLUOR assays were performed to study BC stemness. RNA-sequencing transcriptomic analysis of miR-662-overexpressing BC cells was performed to evaluate gene expression changes.

RESULTS

High levels of hsa-miR-662 (miR-662) in serum from BC patients, at baseline (time of surgery), were associated with future recurrence in bone. At an early-stage of the metastatic disease, miR-662 could mask the presence of BC metastases in bone by inhibiting the differentiation of bone-resorbing osteoclasts. Nonetheless, metastatic miR-662-overexpressing BC cells then progressed as overt osteolytic metastases thanks to increased stem cell-like traits.

CONCLUSIONS

MiR-662 is involved in BC metastasis progression, suggesting it may be used as a prognostic marker to identify BC patients at high risk of metastasis.

MiR-30c facilitates natural killer cell cytotoxicity to lung cancer through targeting GALNT7

BACKGROUND

MicroRNAs (miRNAs) have been reported to play important roles in regulating natural killer (NK) cell cytotoxicity to cancer cells.

OBJECTIVE

This study aimed to investigate the effects and potential mechanism of miR-30c in regulating NK cell cytotoxicity to lung cancer cells.

METHODS

Primary NK cells were derived from the peripheral blood of lung cancer and normal participants. Exosomes were isolated and validated via transmission electron microscopy and nanoparticle tracking analysis. The levels of miR-30c, polypeptide N-acetylgalactosaminyltransferase 7 (GALNT7) and proteins in PI3K/AKT pathway were determined using quantitative real-time polymerase chain reaction or western blot. Tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) levels and the cytotoxicity of effector NK cells to target lung cancer cells were measured via enzyme linked immunosorbent assay, cell apoptosis or xenograft experiments. The relationship between miR-30c and GALNT7 was analyzed by luciferase activity, RNA pull-down and RNA immunoprecipitation assays. And a xenograft mice model was established to verify the effect of miR-30c in regulating NK cell cytotoxicity to lung cancer cells in vivo.

RESULTS

NK cell-derived exosomes carrying miR-30c, and miR-30c level was significantly downregulated in primary NK cells of lung cancer patients. MiR-30c overexpression promoted TNF-α and IFN-γ secretion and enhanced the cytotoxicity of interleukin 2 (IL-2)-treated NK cells to lung cancer cells, while knockdown of miR-30c played an opposite effect in regulating the cytotoxicity of NK cells to lung cancer cells. GALNT7 was a target of miR-30c and was negatively regulated by miR-30c. Besides, miR-30c targeted GALNT7 to exert its function in regulating NK cell cytotoxicity. Furthermore, GALNT7 prompted the activation of PI3K/AKT pathway in NK cells. Additionally, miR-30c overexpression enhanced NK cell cytotoxicity to lung cancer cells and inhibited tumor growth in vivo.

CONCLUSION

miR-30c enhanced NK cell cytotoxicity to lung cancer cells via decreasing GALNT7 and inactivating the PI3K/AKT pathway, suggesting that regulating miR-30c expression maybe a promising approach for enhancing NK cell-based antitumor therapies.

Epigenetic changes induced by pathogenic Chlamydia spp

Chlamydia trachomatis, C. pneumoniae, and C. psittaci, the three Chlamydia species known to cause human disease, have been collectively linked to several pathologies, including conjunctivitis, trachoma, respiratory disease, acute and chronic urogenital infections and their complications, and psittacosis. In vitro, animal, and human studies also established additional correlations, such as between C. pneumoniae and atherosclerosis and between C. trachomatis and ovarian cancer. As part of their survival and pathogenesis strategies as obligate intracellular bacteria, Chlamydia spp. modulate all three major types of epigenetic changes, which include deoxyribonucleic acid (DNA) methylation, histone post-translational modifications, and microRNA-mediated gene silencing. Some of these epigenetic changes may be implicated in key aspects of pathogenesis, such as the ability of the Chlamydia spp. to induce epithelial-to-mesenchymal transition, interfere with DNA damage repair, suppress cholesterol efflux from infected macrophages, act as a co-factor in human papillomavirus (HPV)-mediated cervical cancer, prevent apoptosis, and preserve the integrity of mitochondrial networks in infected host cells. A better understanding of the individual and collective contribution of epigenetic changes to pathogenesis will enhance our knowledge about the biology of Chlamydia spp. and facilitate the development of novel therapies and biomarkers. Pathogenic Chlamydia spp. contribute to epigenetically-mediated gene expression changes in host cells by multiple mechanisms.

The Mutual Relationship between Glycosylation and Non-Coding RNAs in Cancer and Other Physio-Pathological Conditions

Glycosylation, which consists of the enzymatic addition of sugars to proteins and lipids, is one of the most important post-co-synthetic modifications of these molecules, profoundly affecting their activity. Although the presence of carbohydrate chains is crucial for fine-tuning the interactions between cells and molecules, glycosylation is an intrinsically stochastic process regulated by the relative abundance of biosynthetic (glycosyltransferases) and catabolic (glycosidases) enzymes, as well as sugar carriers and other molecules. Non-coding RNAs, which include microRNAs, long non-coding RNAs and circRNAs, establish a complex network of reciprocally interacting molecules whose final goal is the regulation of mRNA expression. Likewise, these interactions are stochastically regulated by ncRNA abundance. Thus, while protein sequence is deterministically dictated by the DNA/RNA/protein axis, protein abundance and activity are regulated by two stochastic processes acting, respectively, before and after the biosynthesis of the protein axis. Consequently, the worlds of glycosylation and ncRNA are closely interconnected and mutually interacting. In this paper, we will extensively review the many faces of the ncRNA-glycosylation interplay in cancer and other physio-pathological conditions.

Bridging Glycomics and Genomics: New Uses of Functional Genetics in the Study of Cellular Glycosylation

All living cells are coated with a diverse collection of carbohydrate molecules called glycans. Glycans are key regulators of cell behavior and important therapeutic targets for human disease. Unlike proteins, glycans are not directly templated by discrete genes. Instead, they are produced through multi-gene pathways that generate a heterogenous array of glycoprotein and glycolipid antigens on the cell surface. This genetic complexity has sometimes made it challenging to understand how glycosylation is regulated and how it becomes altered in disease. Recent years, however, have seen the emergence of powerful new functional genomics technologies that allow high-throughput characterization of genetically complex cellular phenotypes. In this review, we discuss how these techniques are now being applied to achieve a deeper understanding of glyco-genomic regulation. We highlight specifically how methods like ChIP-seq, RNA-seq, CRISPR genomic screening and scRNA-seq are being used to map the genomic basis for various cell-surface glycosylation states in normal and diseased cell types. We also offer a perspective on how emerging functional genomics technologies are likely to create further opportunities for studying cellular glycobiology in the future. Taken together, we hope this review serves as a primer to recent developments at the glycomics-genomics interface.

Bioinformatic Analysis Identified Potentially Prognostic Long Noncoding RNAs and MicroRNAs for Gastric Cancer

Gastric cancer (GC) is the fifth most common malignant tumor in the world. The present study was performed to discover the potential diagnostic and therapeutic long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) of GC. Data used in this study to identify differentially expressed lncRNAs (DElncRNAs) and miRNAs (DEmiRNAs) were obtained from 187 GC tissues and 32 adjacent nontumor tissues. The total clinical data on GC included 187 cases. The above data were from the TCGA database. RStudio/Bioconductor software was used to conduct univariate analysis, the least absolute shrinkage and selection operator (LASSO) Cox, and multivariate Cox proportional risk regression for the DElncRNAs and DEmiRNAs. Clinical information was analyzed through univariate and multivariate Cox analysis. Results: five lncRNAs (AC007785.3, AC079385.3, LINC00392, LINC01729, and U95743.1) and two miRNAs (hsa-miR-3174, hsa-miR-605) were proven to be independent prognostic indicators of GC. Results of the Kaplan-Meier survival analysis showed that AC007785.3, AC079385.3, LINC01729, miR-3174, and miR-605 were significantly correlated with OS of GC. The target genes of AC079385.3, miR-3174, and miR-605 were obtained and clustered mainly on MAPK and cGMP-PKG signaling pathways. The clinical data showed that age and clinicopathologic stage were correlated with the prognosis of GC. Furthermore, AC007785.3 was associated with metastasis of GC, and miR-3174 was associated with the primary tumor condition of GC. We identified three lncRNAs (AC007785.3, AC079385.3, LINC01729), two miRNAs (miR-3174, miR-605), and clinical factors related to the pathogenesis and prognosis of GC. Our predicted results provide a possible entry point for the study of prognostic markers for GC.

miR-30b-5p inhibits proliferation, invasion, and migration of papillary thyroid cancer by targeting GALNT7 via the EGFR/PI3K/AKT pathway

Background

Papillary thyroid carcinoma (PTC) is a common endocrine tumor. Increasing evidence has shown that microRNA dysfunction is involved in the occurrence and development of cancer. The expression of MicroRNA-30b-5p (miR-30b-5p) was down-regulated in PTC; however, its role in the development of PTC is not clear. Hence, this study aimed to explore the role and mechanism of miR-30b-5p in the occurrence and development of PTC.

Methods

The qRT-PCR assay was used to detect the expression of miR-30b-5p in 60 cases of papillary thyroid carcinoma along with their matched non-cancerous tissues. This study explored the biological function of miR-30b-5p by the functional gain and loss experiments in vitro and vivo. The direct target gene of miR-30b-5p and its signaling pathway was identified through bioinformatics analysis, qRT-PCR, western blot, rescue experiments, and double luciferase 3'-UTR report analysis.

Results

This study demonstrated that the low expression of miR-30b-5p is related to poor clinicopathological features. Functionally, the overexpression of miR-30b-5p inhibited the proliferation, invasion, and migration of PTC cells. Bioinformatics and luciferase analysis showed that GALNT7 is the direct and functional target of miR-30b-5p. Moreover, miR-30b-5p inhibited the proliferation of PTC in vivo by inhibiting the expression of GALNT7. The studies on the mechanism have shown that GALNT7 promotes cell proliferation and invasion by activating EGFR/PI3K/AKT kinase pathway, which can be attenuated by the kinase inhibitors.

Conclusions

Overall, miR-30b-5p inhibited the progression of papillary thyroid carcinoma by targeting GALNT7 and inhibiting the EGFR/PI3K/AKT pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02323-x.

Liquid Biopsy in Cervical Cancer: Hopes and Pitfalls

Simple Summary

Cervical cancer is the fourth most common cancer in women worldwide, and its incidence is variably distributed between developed and less-resourced countries, in which socio-economic issues and religious beliefs often limit the widespread diffusion and the access to screening campaigns. In the “liquid biopsy” era, the application of non-invasive and repeatable techniques to the identification of diagnostic, prognostic, and predictive biomarkers might facilitate the management of this disease and, hopefully, improve its outcome. The purpose of this review is to explore the progress status of liquid biopsy in cervical cancer patients. Several methods are described, which include the analysis of circulating tumor cells, the search for pathogenic mutations on circulating tumor DNA, as well as the identification of circulating RNAs, focusing on their potential clinical applications and current limitations.

Abstract

Cervical cancer (CC) is the fourth most common cancer in women worldwide, with about 90% of cancer-related deaths occurring in developing countries. The geographical influence on disease evolution reflects differences in the prevalence of human papilloma virus (HPV) infection, which is the main cause of CC, as well as in the access and quality of services for CC prevention and diagnosis. At present, the most diffused screening and diagnostic tools for CC are Papanicolaou test and the more sensitive HPV-DNA test, even if both methods require gynecological practices whose acceptance relies on the woman’s cultural and religious background. An alternative (or complimentary) tool for CC screening, diagnosis, and follow-up might be represented by liquid biopsy. Here, we summarize the main methodologies developed in this context, including circulating tumor cell detection and isolation, cell tumor DNA sequencing, coding and non-coding RNA detection, and exosomal miRNA identification. Moreover, the pros and cons of each method are discussed, and their potential applications in diagnosis and prognosis of CC, as well as their role in treatment monitoring, are explored. In conclusion, it is evident that despite many advances obtained in this field, further effort is needed to validate and standardize the proposed methodologies before any clinical use.

Identification of autophagy-associated miRNA signature for the cervical squamous cell cancer and high-grade cervical intraepithelial lesions

Cervical cancer markedly threatens women's health worldwide and currently ranks fourth leading cause of cancer mortality in women according to recent global cancer statistics. Recent advances have proven that not only tumor suppressor and oncogenes but also non-coding RNAs including micro RNAs (miRNAs) have significant impact in the development and progression of cervical cancers. Previous studies have identified many cancer-specific miRNAs for the early detection of cervical cancers. However, the diagnostic and prognostic use of autophagy-associated miRNAs for the cervical squamous cell cancer (SCC) cases and high-grade squamous intraepithelial lesion (HSIL) have not been uncovered. In the present study, we revealed that miRNAs are differentially expressed in both cervical SCC and HSIL. A total of 35 HSIL, 35 cervical SCC and 30 healthy controls were enrolled for the present study. Total RNA including miRNAs were isolated from the FFPE tissue samples and miRNA expression levels were quantified by quantitative PCR. Predicted miRNA targets of autophagy related genes were determined using miRNA-target prediction algorithms. MiR-143, miR-372, miR-375 and miR-30c were markedly downregulated in HSIL and cervical SCC. MiR-130a was significantly upregulated in the cervical SCC group compared to HSIL and control groups. MiR-30a, miR-520e, miR-548c and miR-372 were significantly associated with the overall survival of cervical SCC patients and these miRNAs were determined to be significant diagnostic markers as revealed by ROC analysis. Together, these results indicate that autophagy-associated miRNAs are potentially valuable for the differential diagnosis and targeted therapy to cervical cancer.

Comprehensive analysis of ceRNA networks in HPV16- and HPV18-mediated cervical cancers reveals XIST as a pivotal competing endogenous RNA

Cervical cancer (CC) is one of the most common cancers in women worldwide, being closely related to high-risk human papillomavirus (HR-HPVs). After a particular HR-HPV infects a cervical cell, transcriptional changes in the host cell are expected, including the regulation of lncRNAs, miRNAs, and mRNAs. Such transcripts may work independently or integrated in complex molecular networks - as in competing endogenous RNA (ceRNA) networks. In our research, we gathered transcriptome data from samples of HPV16/HPV18 cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC), from The Cancer Genome Atlas (TCGA) project. Using GDCRNATools, we identified ceRNA networks that differentiate HPV16- from HPV18-mediated CESC. For HPV16-CESC, three lncRNA-mRNA co-expressed pairs were reported, all led by the X-inactive specific transcript (XIST): XIST | DLG5, XIST | LGR4, and XIST | ZNF81. The XIST | LGR4 and XIST | ZNF81 pairs shared 11 miRNAs, suggesting an increased impact on their final biological effect. XIST also stood out as an important lncRNA in HPV18-CESC, leading 35 of the 42 co-expressed pairs. Some mRNAs, such as ADAM9 and SLC38A2, emerged as important players in the ceRNA regulatory networks due to sharing a considerable amount of miRNAs with XIST. Furthermore, some XIST-associated axes, namely XIST | miR-23a-3p | LGR4 and XIST | miR-30b-5p or miR-30c-5p or miR-30e-5p I ADAM9, had a significant impact on the overall survival of HPV16- and HPV18-CESC patients, respectively. Together, these data suggest that XIST has an important role in HPV-mediated tumorigenesis, which may implicate different molecular signatures between HPV16 and HPV18-associated tumors.

Epigenetic Regulation of Glycosylation in Cancer and Other Diseases

In the last few decades, the newly emerging field of epigenetic regulation of glycosylation acquired more importance because it is unraveling physiological and pathological mechanisms related to glycan functions. Glycosylation is a complex process in which proteins and lipids are modified by the attachment of monosaccharides. The main actors in this kind of modification are the glycoenzymes, which are translated from glycosylation-related genes (or glycogenes). The expression of glycogenes is regulated by transcription factors and epigenetic mechanisms (mainly DNA methylation, histone acetylation and noncoding RNAs). This review focuses only on these last ones, in relation to cancer and other diseases, such as inflammatory bowel disease and IgA1 nephropathy. In fact, it is clear that a deeper knowledge in the fine-tuning of glycogenes is essential for acquiring new insights in the glycan field, especially if this could be useful for finding novel and personalized therapeutics.

Elevated GALNT10 expression identifies immunosuppressive microenvironment and dismal prognosis of patients with high grade serous ovarian cancer

High grade ovarian serous cancer (HGSC) is a malignant disease with high mortality. Glycosylation plays important roles in tumor invasion and immune evasion, but its effect on the immune microenvironment of HGSC remains unclear. This study examined the association of glycosyltransferase expression with HGSC prognosis and explored the underlying mechanism using clinical specimens and integrated bioinformatic analyses. We identified a cluster of 15 glycogenes associated with reduced overall survival, and GALNT10 was found to be an independent predictor of HGSC prognosis. The high GALNT10 expression was associated with increased regulatory CD4+ T cells infiltration and decreased granzyme B expression in CD8+ T cells. The expression of GALNT10 and its product, Tn antigen, in HGSC specimens was associated with the increased infiltration of M2 macrophages and neutrophils, and the decreased infiltration of CD3+ T cells, NK cells, and B cells. Taken collectively, high GALNT10 expression confers with immunosuppressive microenvironment to promote tumor progression and predicts poor clinical outcomes in HGSC patients.

An integrated approach for mining precise RNA-based cervical cancer staging biomarkers

Since international federation of gynecology and obstetrics (FIGO) staging is mainly based on clinical assessment, an integrated approach for mining RNA based biomarkers for understanding the molecular deregulation of signaling pathways and RNAs in cervical cancer was proposed in this study. Publicly available data were mined for identifying significant RNAs after patient staging. Significant miRNA families were identified from mRNA-miRNA and lncRNA-miRNA interaction network analyses followed by stage specific mRNA-miRNA-lncRNA association network generation. Integrated bioinformatic analyses of selected mRNAs and lncRNAs were performed. Results suggest that HBA1, HBA2, HBB, SLC2A1, CXCL10 (stage I), PKIA (stage III) and S100A7 (stage IV) were important. miRNA family enrichment of interacting miRNA partners of selected RNAs indicated the enrichment of let-7 family. Assembly of collagen fibrils and other multimeric structures_Homosapiens_R-HSA-2022090 in pathway analysis and progesterone_CTD_00006624 in DSigDB analysis were the most significant and SLC2A1, hsa-miR-188-3p, hsa-miR-378a-3p and hsa-miR-150-5p were selected as survival markers.

microRNAs: New prognostic, diagnostic, and therapeutic biomarkers in cervical cancer

Cervical cancer is as a kind of cancer beginning from the cervix. Given that cervical cancer could be observed in women who infected with papillomavirus, regular oral contraceptives, and multiple pregnancies. Early detection of cervical cancer is one of the most important aspects of the therapy of this malignancy. Despite several efforts, finding and developing new biomarkers for cervical cancer diagnosis are required. Among various prognostic, diagnostic, and therapeutic biomarkers, miRNA have been emerged as powerful biomarkers for detection, treatment, and monitoring of response to therapy in cervical cancer. Here, we summarized various miRNAs as an employable platform for prognostic, diagnostic, and therapeutic biomarkers in the treatment of cervical cancer.

Alterations in the glycome after HDAC inhibition impact oncogenic potential in epigenetically plastic SW13 cells

Background

Defects in the type and degree of cellular glycosylation impact oncogenesis on multiple levels. Although the type of glycosylation is determined by protein sequence encoded by the genome, the extent and modifications of glycosylation depends on the activity of biosynthetic enzymes and recent data suggests that the glycome is also subject to epigenetic regulation. This study focuses on the ability of HDAC inhibition to alter glycosylation and to lead to pro-oncogenic alterations in the glycome as assessed by metastatic potential and chemoresistance.

Methods

Epigenetically plastic SW13 adrenocortical carcinoma cells were treated with FK228, an HDAC inhibitor with high affinity for HDAC1 and, to a lesser extent, HDAC2. In comparing HDAC inhibitor treated and control cells, differential expression of glycome-related genes were assessed by microarray. Differential glycosylation was then assessed by lectin binding arrays and the ability of cellular proteins to bind to glycans was assessed by glycan binding arrays. Differential sensitivity to paclitaxel, proliferation, and MMP activity were also assessed.

Results

Treatment with FK228 alters expression of enzymes in the biosynthetic pathways for a large number of glycome related genes including enzymes in all major glycosylation pathways and several glycan binding proteins. 84% of these differentially expressed glycome-related genes are linked to cancer, some as prognostic markers and others contributing basic oncogenic functions such as metastasis or chemoresistance. Glycan binding proteins also appear to be differentially expressed as protein extracts from treated and untreated cells show differential binding to glycan arrays. The impact of differential mRNA expression of glycosylation enzymes was documented by differential lectin binding. However, the assessment of changes in the glycome is complicated by the fact that detection of differential glycosylation through lectin binding is dependent on the methods used to prepare samples as protein-rich lysates show different binding than fixed cells in several cases. Paralleling the alterations in the glycome, treatment of SW13 cells with FK228 increases metastatic potential and reduces sensitivity to paclitaxel.

Conclusions

The glycome is substantially altered by HDAC inhibition and these changes may have far-reaching impacts on oncogenesis.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-5129-4) contains supplementary material, which is available to authorized users.

MiR-154 inhibits the growth of laryngeal squamous cell carcinoma by targeting GALNT7

MicroRNAs are critical regulators of the development and progression of laryngeal squamous cell carcinoma (LSCC). However, the role of microRNA-154 (miR-154) in the development and progression of LSCC has not been clarified. We found that down-regulated miR-154 expression in LSCC tissues was associated with poorer prognosis in LSCC patients. MiR-154 over-expression inhibited the proliferation, clonogenicity, and migration of LSCC cells and induced cell cycle arrest, which were reversed by miR-154 inhibition. MiR-154 targeted GALNT7 expression by reducing GALNT7-regulated luciferase activity in LSCC cells while up-regulating GALNT7 mRNA transcription in LSCC tissues and cells. GALNT7 silencing significantly attenuated the proliferation, clonogenicity, and migration of LSCC cells and induced cell cycle arrest. Finally, intravenous treatment with lentivirus for miR-154, but not scrambled control miRNA, significantly restrained the growth of implanted LSCC Hep-2 tumors and decreased the tumor mass by reducing GALNT7 expression in mice. Therefore, miR-154 may serve as a novel prognostic marker and therapeutic target for LSCC.

High expression of GALNT7 promotes invasion and proliferation of glioma cells

Polypeptide-N-acetyl-galactosaminlytransferase 7 (GALNT7), a member of the GalNAc-transferase family, has not been previously evaluated as a prognostic factor of glioblastoma (GBM) or low-grade glioma (LGG). Based on The Cancer Genome Atlas database and bioinformatics analyses, the expression of GALNT7 was demosntrated to be higher in GBM and LGG tissues than in normal brain tissue. The expression levels of GANLT7 were associated with age, tumor grade, survival rate, disease-free survival time and overall survival time. Gene correlation and gene-set enrichment analyses suggested that GALNT7 may affect the proliferative and invasive abilities of glioma cells through multiple signaling pathways, including regulation of the actin cytoskeleton, natural killer cell-mediated cytotoxicity, the janus kinase-signal transducer and activator of transcription (STAT) signaling pathway, cell adhesion molecules and extracellular matrix receptor interaction pathways. Furthermore, 5 target genes of GALNT7 involved in these signaling pathways were identified, including Crk, Rac family small GTPase 1, STAT3, poliovirus receptor and Tenascin C. In summary, high expression of GALNT7 was associated with poor prognosis of glioma, and may be used as an effective biomarker of glioma.

The Role of Non-Coding RNAs and Isothiocyanates in Cancer

Cancer is the second leading cause of mortalities in the United States, only exceeded by heart disease. Current cancer treatments include chemotherapy, surgery, and/or radiation. Due to the often harsh effects of current cancer therapies, investigators are focusing their efforts on cancer prevention mediated by dietary phytochemicals. Since the discovery that cancer can be initiated by and progressed through both genetic and epigenetic pathways, there has been a significant surge in studies on epigenetic effects mediated by nutritive compounds. Isothiocyanates, naturally occurring molecules found in cruciferous vegetables, have been documented to exhibit many anticarcinogenic activities. Although isothiocyanates have been extensively documented as key players in epigenetic processes such as DNA methylation and histone modifications, their effects on non-coding RNAs is understudied. Non-coding RNAs are molecules that target mRNA production and repress protein translation and are known to be dysregulated in various human malignancies. Studies have used non-coding RNAs as novel targets for exploration in cancer therapy. This review focuses on the exploration of isothiocyanates and their effect on non-coding RNAs in cancer prevention and therapy.

Long non-coding RNA-SNHG7 acts as a target of miR-34a to increase GALNT7 level and regulate PI3K/Akt/mTOR pathway in colorectal cancer progression

Background

Colorectal cancer (CRC) arises in a multistep molecular network process, which is from either discrete genetic perturbation or epigenetic dysregulation. The long non-coding RNAs (lncRNAs), emerging as key molecules in human malignancy, has become one of the hot topics in RNA biology. Aberrant O-glycosylation is a well-described hallmark of many cancers. GALNT7 acts as a glycosyltransferase in protein O-glycosylation, involving in the occurrence and development of CRC.

Methods

The microarrays were used to survey the lncRNA and mRNA expression profiles of primary CRC cell line SW480 and metastatic CRC cell line SW620. Cell proliferation, migration, invasion, and apoptosis were assayed. Xenograft mouse models were used to determine the role of lncRNA-SNHG7 in CRC in vivo. In addition, CNC analysis and competing endogenous analysis were used to detect differential SNHG7 and relational miRNAs expression in CRC cell lines.

Results

SNHG7 expression showed a high fold (SW620/SW480) in CRC microarrays. The CRC patients with high expression of SNHG7 had a significantly poor prognosis. Furthermore, SNHG7 promoted CRC cell proliferation, metastasis, mediated cell cycle, and inhibited apoptosis. SNHG7 and GALNT7 were observed for co-expression by CNC analysis, and a negative correlation of SNHG7 and miR-34a were found by competing endogenous RNA (ceRNA) analysis. Further results indicated that SNHG7 facilitated the proliferation and metastasis as a competing endogenous RNA to regulate GALNT7 expression by sponging miR-34a in CRC cell lines. SNHG7 also played the oncogenic role in regulating PI3K/Akt/mTOR pathway by competing endogenous miR-34a and GALNT7.

Conclusion

The CRC-related SNHG7 and miR-34a might be implicated in CRC progression via GALNT7, suggesting the potential usage of SNHG7/miR-34a/GALNT7 axis in CRC treatment.

Electronic supplementary material

The online version of this article (10.1186/s13045-018-0632-2) contains supplementary material, which is available to authorized users.