MiR-127 and miR-376a act as tumor suppressors by in vivo targeting of COA1 and PDIA6 in giant cell tumor of bone

A Comprehensive Pan-Cancer Analysis of Cytochrome C Oxidase Assembly Factor 1 (COA1) Reveals Instrumental Role of Mitochondrial Protein Assembly in Cancer that Modulates Disease Progression and Prognostic Outcome

Cytochrome c oxidase assembly factor 1 (COA1), a mitochondrial respiratory chain complex assembly factor protein of inner mitochondrial membrane (IMM), is involved in translating many mitochondrial components and assembling nuclear-encoded components within mitochondria. Given the lack of extensive research on COA1 in cancer, this study undertakes a comprehensive pan-cancer analysis of COA1, which is overexpressed across various cancer types, shedding light on its multifaceted role in tumorigenesis, prognosis, and tumor microenvironment (TME) modulation. Leveraging bioinformatics tools and public databases, we elucidated its potential as a diagnostic cancer biomarker as well as a target for novel anti-cancer therapeutics. Gene expression analysis using "TIMER2.0", "UALCAN" and "GEPIA2" platforms, supported by protein expression data, revealed a significant correlation between COA1 upregulation and poor prognosis in Kaplan-Meir analysis, underscoring its clinical relevance. Additionally, genetic mutation analysis of COA1 with the help of "cBioPortal" warrants further exploration into its functional significance. Moreover, our investigation of the tumor microenvironment unveiled the interplay of COA1 with fibroblast and T cell infiltration implicating the role of COA1 in the tumor immune microenvironment. Furthermore, COA1-related gene enrichment study in "GeneMANIA" and pathway cross-talk analysis with Gene Ontology (GO) gene sets established comprehensive clarifications about the molecular pathways and protein networks associated with COA1 deregulation. Overall, this study lays a sturdy foundation to support future research endeavors targeting COA1, unraveling the molecular mechanisms underlying COA1 deregulation, and exploring its therapeutic potential in cancer.

LncRNA NUTM2A-AS1 silencing inhibits glioma via miR-376a-3p/YAP1 axis

The lncRNA NUTM2A-AS1 has been shown to be dysregulated in gastric cancer, while the roles in glioma is unclear. The aim of this study was to investigate the roles and potential mechanisms of lncRNA NUTM2A-AS1 in the proliferation and apoptosis of glioma cells. The StarBase software and dual luciferase reporter assay were used to identify the relationship between lncRNA NUTM2A-AS1 and miR-376a-3p, and miR-376a-3p and YAP1. The expression of lncRNA NUTM2A-AS1, miR-376a-3p, and YAP1 in human glioma cell lines was detected by qRT-PCR. MTT and flow cytometry were used to detect the effects of lncRNA NUTM2A-AS1 or miR-376a-3p on the proliferation and apoptosis of U251 and A172 cells, respectively. In addition, changes of Bax and Bcl-2 expression in glioma cells were further verified by western blotting and qRT-PCR. The results showed that the expression of lncRNA NUTM2A-AS1 was elevated in glioma cell lines, while miR-376a-3p was decreased. LncRNA NUTM2A-AS1 was negatively correlated with miR-376a-3p. Silencing of lncRNA NUTM2A-AS1 enhanced the levels of miR-376a-3p, leading to reduced cell proliferation and increased apoptosis in glioma cells. YAP1 was a direct target of miR-376a-3p, and it was negatively regulated by miR-376a-3p in U251 and A172 cells. Further mechanistic studies suggested that miR-376a-3p reduced glioma cell proliferation and increased apoptosis by inhibiting YAP1 expression. In addition, lncRNA NUTM2A-AS1 positively regulated of YAP1 expression in glioma cells. In conclusion, silencing of lncRNA NUTM2A-AS1 inhibited proliferation and induced apoptosis in human glioma cells via the miR-376a-3p/YAP1 axis.

More than Just Bread and Wine: Using Yeast to Understand Inherited Cytochrome Oxidase Deficiencies in Humans

Inherited defects in cytochrome c oxidase (COX) are associated with a substantial subset of diseases adversely affecting the structure and function of the mitochondrial respiratory chain. This multi-subunit enzyme consists of 14 subunits and numerous cofactors, and it requires the function of some 30 proteins to assemble. COX assembly was first shown to be the primary defect in the majority of COX deficiencies 36 years ago. Over the last three decades, most COX assembly genes have been identified in the yeast Saccharomyces cerevisiae, and studies in yeast have proven instrumental in testing the impact of mutations identified in patients with a specific COX deficiency. The advent of accessible genome-wide sequencing capabilities has led to more patient mutations being identified, with the subsequent identification of several new COX assembly factors. However, the lack of genotype-phenotype correlations and the large number of genes involved in generating a functional COX mean that functional studies must be undertaken to assign a genetic variant as being causal. In this review, we provide a brief overview of the use of yeast as a model system and briefly compare the COX assembly process in yeast and humans. We focus primarily on the studies in yeast that have allowed us to both identify new COX assembly factors and to demonstrate the pathogenicity of a subset of the mutations that have been identified in patients with inherited defects in COX. We conclude with an overview of the areas in which studies in yeast are likely to continue to contribute to progress in understanding disease arising from inherited COX deficiencies.

Siglec-15 as a New Perspective Therapy Target in Human Giant Cell Tumor of Bone

The main features of a giant cell tumor of bone (GCTB) are frequent recurrence and aggressive osteolysis, which leads to a poor prognosis in patients. Although the treatment methods for a GCTB, such as scraping and resection, effectively inhibit the disease, the tendency toward malignant transformation remains. Therefore, it is important to identify new treatment methods for a GCTB. In this study, we first found high Siglec-15 expression in GCTB tissues, which was significantly associated with Campanacci staging and tumor recurrence. In Spearman's analysis, Siglec-15 expression was significantly correlated with Ki-67 levels in tumor tissues. In vitro, the mRNA and protein levels of Siglec-15 were high in GCTB stromal cells (Hs737. T), and Siglec-15 knockdown inhibited the biological characteristics of GCTB stromal cells. The RNA sequencing results enabled a prediction of the downstream genes by using the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and MCODE analyses, and the findings showed that CXCL8 was significantly regulated by Siglec-15 and might be a promising downstream target gene of Siglec-15. Therefore, Siglec-15 may be a potential immunotherapy target for a GCTB.

Mitochondrial Genetic and Epigenetic Regulations in Cancer: Therapeutic Potential

Mitochondria are dynamic organelles managing crucial processes of cellular metabolism and bioenergetics. Enabling rapid cellular adaptation to altered endogenous and exogenous environments, mitochondria play an important role in many pathophysiological states, including cancer. Being under the control of mitochondrial and nuclear DNA (mtDNA and nDNA), mitochondria adjust their activity and biogenesis to cell demands. In cancer, numerous mutations in mtDNA have been detected, which do not inactivate mitochondrial functions but rather alter energy metabolism to support cancer cell growth. Increasing evidence suggests that mtDNA mutations, mtDNA epigenetics and miRNA regulations dynamically modify signalling pathways in an altered microenvironment, resulting in cancer initiation and progression and aberrant therapy response. In this review, we discuss mitochondria as organelles importantly involved in tumorigenesis and anti-cancer therapy response. Tumour treatment unresponsiveness still represents a serious drawback in current drug therapies. Therefore, studying aspects related to genetic and epigenetic control of mitochondria can open a new field for understanding cancer therapy response. The urgency of finding new therapeutic regimens with better treatment outcomes underlines the targeting of mitochondria as a suitable candidate with new therapeutic potential. Understanding the role of mitochondria and their regulation in cancer development, progression and treatment is essential for the development of new safe and effective mitochondria-based therapeutic regimens.

LncRNA FOXD3-AS1 promotes breast cancer progression by mediating ARF6

BACKGROUND

Breast cancer is one of the most common malignant tumor in women. The high metastatic characteristics cause a high mortality rate of breast cancer. Increasing number of studies have indicated that long non-coding RNAs (lncRNAs) play key roles in the progression of human cancers including breast cancer. In this study, we studied the expression and molecular mechanisms of lncRNA FOXD3-AS1 in breast cancer.

METHODS

The expression of lncRNA FOXD3-AS1 was analyzed by TCGA database and RT-qPCR assay. CCK8 assay was used to measure cell proliferation ability. Cell migration and invasion capacities were detected by transwell assay. Potential targets of lncRNA and miRNA were predicted by bioinformatic tools. The targeting relationship between genes was verified by dual-luciferase reporter assay. The nude mice tumor model was performed to study the effect of FOXD3-AS1 on breast cancer in vivo. Protein expression was detected by western blot.

RESULTS

In the present study, we found that the FOXD3-AS1 expression was significantly increased in breast cancer tissues compared with normal tissues and involved in the poor prognosis of patients. Functionally, knockdown of FOXD3-AS1 suppressed cell proliferation and metastasis abilities in vitro, and tumor growth in vivo. Mechanistically, FOXD3-AS1 functioned as a competing endogenous RNA (ceRNA) to upregulate ARF6 expression by targeting miR-127-3p. In addition, the roles of FOXD3-AS1 on cell proliferation and metastasis were achieved through miR-127-3p/ARF6 axis.

CONCLUSION

In summary, our results reported the regulatory mechanism of FOXD3-AS1 in breast cancer progression by targeting miR-127-3p/ARF6 axis to affect cell proliferation, migration, invasion and tumor growth.

Non-coding RNAs and glioblastoma: Insight into their roles in metastasis

Glioma, also known as glioblastoma multiforme (GBM), is the most prevalent and most lethal primary brain tumor in adults. Gliomas are highly invasive tumors with the highest death rate among all primary brain malignancies. Metastasis occurs as the tumor cells spread from the site of origin to another site in the brain. Metastasis is a multifactorial process, which depends on alterations in metabolism, genetic mutations, and the cancer microenvironment. During recent years, the scientific study of non-coding RNAs (ncRNAs) has led to new insight into the molecular mechanisms involved in glioma. Many studies have reported that ncRNAs play major roles in many biological procedures connected with the development and progression of glioma. Long ncRNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs) are all types of ncRNAs, which are commonly dysregulated in GBM. Dysregulation of ncRNAs can facilitate the invasion and metastasis of glioma. The present review highlights some ncRNAs that have been associated with metastasis in GBM. miRNAs, circRNAs, and lncRNAs are discussed in detail with respect to their relevant signaling pathways involved in metastasis.

PDIA6 promotes pancreatic cancer progression and immune escape through CSN5-mediated deubiquitination of β-catenin and PD-L1

Protein Disulfide Isomerase Family A Member 6 (PDIA6) is an endoplasmic reticulum protein that is capable of catalyzing protein folding and disulfide bond formation. Abnormally elevated expression of PDIA6 has been reported to predict poor outcomes in various cancers. Herein, gain-of- and loss-of-function experiments were performed to investigate how PDIA6 participated in the carcinogenesis of pancreatic cancer (PC). By analyzing the protein expression of PDIA6 in 28 paired PC and para carcinoma specimens, we first found that PDIA6 expression was higher in PC samples. Both the overall survival and disease-free survival rates of PC patients with higher PDIA6 expression were poorer than those with lower PDIA6 (n = 178). Furthermore, knockdown of PDIA6 impaired the malignancies of PC cells - suppressed cell proliferation, invasion, migration, cisplatin resistance, and xenografted tumor growth. PDIA6-silenced PC cells were more sensitive to cytotoxic natural killer (NK) cells. Overexpression of PDIA6 had opposite effects on PC cells. Interestingly, COP9 signalosome subunit 5 (CSN5), a regulator of E3 ubiquitin ligases known to promote deubiquitination of its downstream targets, was demonstrated to interact with PDIA6, and its expression was increased in PC cells overexpressing PDIA6. Additionally, PDIA6 overexpression promoted deubiquitination of β-catenin and PD-L1 and subsequently upregulated their expression in PC cells. These alterations were partly reversed by CSN5 shRNA. Collectively, the above results demonstrate that PDIA6 contributes to PC progression, which may be associated with CSN5-regulated deubiquitination of β-catenin and PD-L1. Our findings suggest PDIA6 as a potential target for the treatment of PC.

microRNAs and bone tumours: Role of tiny molecules in the development and progression of chondrosarcoma, of giant cell tumour of bone and of Ewing's sarcoma

The increasing interest on microRNAs (miRNAs), small non-coding RNA molecules containing about 22 nucleotides, about their biological functions led researchers to discover that they are actively involved in several biological processes. In the last decades, miRNAs become one of the most topic of cancer research. miRNAs, thanks to their function, are the perfect molecules to modulate multiple signaling pathways and gene expression in cancer, with the consequent capacity to modulate cancerous processes, such as cellular proliferation, invasion, metastasis and chemoresistance in various tumours. In the last years, several studies have demonstrated the role of miRNAs in their pathophysiology, but little we know about the underlying mechanism that lead to bone tumours like chondrosarcoma (COS), giant cell tumour of bone (GCTB) and Ewing sarcoma (EWS) to still be highly aggressive and resistant tumours. An exploration of the role of miRNAs in the biology of them will permit to researchers to find new molecular mechanisms that can be used to develop new and more effective therapies against these bone tumours. Here we present a comprehensive study of the latest discoveries which have been performed in relation to the role of miRNAs in the neoplastic processes which characterize COS, EWS and GCTB, demonstrating how these tiny molecules can act as tumour promoters or as tumour suppressors and how they can be used for improving therapeutic approaches.

PDIA6 contributes to aerobic glycolysis and cancer progression in oral squamous cell carcinoma

Background/objective

Accumulated evidence has demonstrated that aerobic glycolysis serves as a regulator of tumor cell growth, invasion, and angiogenesis. Herein, we explored the role of protein disulfide isomerase family 6 (PDIA6) in the aerobic glycolysis and the progression of oral squamous cell carcinoma (OSCC).

Methods

The expression pattern of PDIA6 in OSCC tissues was determined by qPCR and western blotting. Lentivirus and small interfering RNAs (siRNAs) were introduced into cells to upregulate and downregulate PDIA6 expression. CCK-8, flow cytometry, transwell, and xenotransplantation models were applied to detect cell proliferation, apoptosis, migration, invasion, and tumorigenesis, respectively.

Results

A high expression pattern of PDIA6 was observed in OSCC tissues, which was closely associated with lower overall survival and malignant clinical features in OSCC. Compared with the control group, overexpression of PDIA6 induced significant enhancements in cell growth, migration, invasiveness, and tumorigenesis and decreased cell apoptosis, while knockdown of PDIA6 caused opposite results. In addition, overexpression of PDIA6 increased glucose consumption, lactate production, and ATP level in OSCC cells.

Conclusion

This study demonstrated that PDIA6 expression was elevated in OSCC tissues, and overexpression of it promoted aerobic glycolysis and OSCC progression.

MicroRNA Profile for Diagnostic and Prognostic Biomarkers in Thyroid Cancer

The challenge in managing thyroid nodules is to accurately diagnose the minority of those with malignancy. We aimed to identify diagnostic and prognostic miRNA markers for thyroid nodules. In a discovery cohort, we identified 20 candidate miRNAs to differentiate between noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP) and papillary thyroid carcinomas (PTC) by using the high-throughput small RNA sequencing method. We then selected three miRNAs (miR-136, miR-21, and miR-127) that were differentially expressed between the PTC follicular variant and other variants in The Cancer Genome Atlas data. High expression of three miRNAs differentiated thyroid cancer from nonmalignant tumors, with an area under curve (AUC) of 0.76-0.81 in an independent cohort. In patients with differentiated thyroid cancer, the high-level expression of the three miRNAs was an independent indicator for both distant metastases and recurrent or persistent disease. In patients with PTC, a high expression of miRNAs was associated with an aggressive histologic variant, extrathyroidal extension, distant metastasis, or recurrent or persistent disease. Three miRNAs may be used as diagnostic markers for differentiating thyroid cancers from benign tumors and tumors with extremely low malignant potential (NIFTP), as well as prognostic markers for predicting the risk of recurrent/persistent disease for differentiated thyroid cancer.

Bta-miR-376a Targeting KLF15 Interferes with Adipogenesis Signaling Pathway to Promote Differentiation of Qinchuan Beef Cattle Preadipocytes

Intramuscular fat (IMF) is a quality index associated with the taste and juiciness of meat. The deposition of IMF is affected by genetic and non-genetic factors, such as age, slaughter location, gender of the animal, and diet. Micro-ribonucleic acids (miRNA) are transcriptional regulators involved in adipogenesis, but the specific role of miR-376a in regulation of bovine adipocytes remains unknown. Our findings indicated that miR-376a was a potential negative regulator of bovine adipocyte differentiation. A bta-miR-376a mimic inhibited mRNA and protein expression of the marker genes, CDK1, CDK2, PCNA, C/EBPα, FAS, and PPAR γ, and significantly reduced ratios (%) of S-phase cells, the number of cells stained with 5-ethynyl-2'-deoxyuridine, and adipocyte proliferation. Oil red O staining and triglyceride content analysis also confirmed that bta-miR-376a was involved in adipocyte differentiation. Luciferase activities confirmed that Krüppel-like transcription factor 15 (KLF15) was a direct target gene of bta-miR-376a, and that KLF15 was a key transcription factor in adipogenesis. Therefore, bta-miR-376a might be a target for increasing beef IMF.

Cytochrome C Oxidase Assembly Factor 1 Homolog Predicts Poor Prognosis and Promotes Cell Proliferation in Colorectal Cancer by Regulating PI3K/AKT Signaling

Purpose

Colorectal cancer (CRC) is one of the most common malignancies in the world. The prognosis of advanced CRC is still poor. The purpose of this study was to identify a gene expression profile associated with CRC that may contribute to the early diagnosis of CRC and improve patient prognosis.

Patients and Methods

Five pairs of CRC tissues and paracancerous tissues were used to identify causative genes using microarray assays. The prognostic value of Cytochrome C Oxidase Assembly Factor 1 Homolog (COA1) in CRC was assessed in 90 CRC patients. Loss-of-function assays, cell proliferation assays using Celigo and MTT, colony formation assays, a subcutaneous xenograft mouse model, and apoptosis assays were used to define the effects of downregulation of COA1 in CRC cells in vitro and in vivo. The underlying molecular mechanisms of COA1 in CRC were also investigated.

Results

The causative gene COA1 was identified through microarray analysis. COA1 expression in CRC was notably associated with pathologic differentiation, tumor size, and tumor depth. COA1 expression may act as an independent prognostic factor for overall survival of CRC. Knockdown of COA1 inhibited the proliferation of CRC cells in vitro and the tumorigenicity of CRC cells in vivo. Decreased COA1 expression induced apoptosis of CRC cells. Based on the microarray assay results comparing HCT116 cells transfected with lentivirus encoding anti-COA1 shRNA or negative control shRNA, ingenuity pathway analysis (IPA) revealed that the PI3K/AKT signaling pathway was significantly enriched. Moreover, CCND1, mTOR, AKT1, and MDM2 were identified as the downstream genes of COA1.

Conclusion

These findings demonstrate that COA1 promotes CRC cell proliferation and inhibits apoptosis by regulating the PI3K/AKT signaling pathway. Our results implicate COA1 as a potential oncogene involved in tumor growth and progression of CRC.

CircSEC31A Promotes the Malignant Progression of Non-Small Cell Lung Cancer Through Regulating SEC31A Expression via Sponging miR-376a

Background

Circular RNAs (circRNAs) have recently been shown as important regulators in the pathogenesis of non-small cell lung cancer (NSCLC). The purpose of this work was to explore the precise parts played by circRNA SEC31 homolog A (circSEC31A, hsa_circ_0001421) in NSCLC malignant progression.

Methods

The expression levels of circSEC31A, miR-376a and SEC31 homolog A (SEC31A) were gauged by quantitative real-time polymerase chain reaction (qRT-PCR) or Western blot. Subcellular fractionation assay was used to determine the subcellular localization of circSEC31A, and RNase R assay was performed to assess the stability of circSEC31A. Cell migration and invasion were detected by transwell assay, and cell apoptosis was evaluated using flow cytometry. Measurement of glucose consumption, lactate production and adenosine triphosphate (ATP) level were done using corresponding assay kits. The targeted interactions among circSEC31A, miR-376a and SEC31A were confirmed by the dual-luciferase reporter and RNA pull-down assays. Animal studies were performed to observe the role of circSEC31A in tumor growth in vivo.

Results

Our data indicated that circSEC31A and SEC31A were upregulated in NSCLC tissues and cells. CircSEC31A knockdown suppressed NSCLC cell migration, invasion, glycolysis and promoted apoptosis in vitro, as well as hindered tumor growth in vivo. Mechanistically, circSEC31A directly interacted with miR-376a, and circSEC31A depletion regulated NSCLC cell malignant progression by miR-376a. Moreover, SEC31A was a functional target of miR-376a, and it mediated the regulatory impact of miR-376a overexpression on NSCLC cell progression. Furthermore, circSEC31A controlled SEC31A expression through acting as a miR-376a sponge.

Conclusion

Our findings first identified that the knockdown of circSEC31A suppressed NSCLC malignant progression at least partly through modulating SEC31A expression by acting as a miR-376a sponge, providing a novel molecular target of NSCLC therapy.

LncRNA TTN‑AS1 promotes endometrial cancer by sponging miR‑376a‑3p

Increasing research has demonstrated that lncRNAs participate in the development of multiple cancer types. However, the role of TTN‑AS1 in endometrial cancer (EC) remains unknown. The present study aimed to explore the function of titin‑antisense RNA1 (TTN‑AS1) in EC progression and the underlying mechanisms. qRT‑PCR was performed to assess the TTN‑AS1 expression patterns in EC tissues and cell lines. Loss of function experiments were carried out to estimate the effects of TTN‑AS1 on EC cell proliferation, migration and invasion. To reveal the underlying mechanisms, informatics tools were used to predict the targets. Rescue experiments were performed to investigate the TTN‑AS1‑regulated miR‑376a‑3p/pumilio homolog 2 (PUM2) axis involved. The results of the present study revealed that TTN‑AS1 was highly expressed in both EC tissues and cell lines, and TTN‑AS1 knockdown inhibited EC cell proliferation, migration and invasion. With respect to the mechanisms, miR‑376a‑3p was revealed to be targeted by TTN‑AS1, and reversed the effects on EC development induced by TTN‑AS1. In addition, PUM2 was positively regulated by TTN‑AS1, and miR‑376a‑3p mediated the regulation between them. Furtherly, in vivo experiments confirmed the results. Collectively, TTN‑AS1 enhanced EC cell proliferation and metastasis by targeting the miR‑376a‑3p/PUM2 axis, which may shed light on EC diagnosis and treatment.

Integrative Analysis of Membrane Proteome and MicroRNA Reveals Novel Lung Cancer Metastasis Biomarkers

Lung cancer is one of the most common human cancers both in incidence and mortality, with prognosis particularly poor in metastatic cases. Metastasis in lung cancer is a multifarious process driven by a complex regulatory landscape involving many mechanisms, genes, and proteins. Membrane proteins play a crucial role in the metastatic journey both inside tumor cells and the extra-cellular matrix and are a viable area of research focus with the potential to uncover biomarkers and drug targets. In this work we performed membrane proteome analysis of highly and poorly metastatic lung cells which integrated genomic, proteomic, and transcriptional data. A total of 1,762 membrane proteins were identified, and within this set, there were 163 proteins with significant changes between the two cell lines. We applied the Tied Diffusion through Interacting Events method to integrate the differentially expressed disease-related microRNAs and functionally dys-regulated membrane protein information to further explore the role of key membrane proteins and microRNAs in multi-omics context. Has-miR-137 was revealed as a key gene involved in the activity of membrane proteins by targeting MET and PXN, affecting membrane proteins through protein-protein interaction mechanism. Furthermore, we found that the membrane proteins CDH2, EGFR, ITGA3, ITGA5, ITGB1, and CALR may have significant effect on cancer prognosis and outcomes, which were further validated in vitro. Our study provides multi-omics-based network method of integrating microRNAs and membrane proteome information, and uncovers a differential molecular signatures of highly and poorly metastatic lung cancer cells; these molecules may serve as potential targets for giant-cell lung metastasis treatment and prognosis.

Differences between Well-Differentiated Neuroendocrine Tumors and Ductal Adenocarcinomas of the Pancreas Assessed by Multi-Omics Profiling

Most pancreatic neuroendocrine tumors (PNETs) are indolent, while pancreatic ductal adenocarcinomas (PDACs) are particularly aggressive. To elucidate the basis for this difference and to establish the biomarkers, by using the deep sequencing, we analyzed somatic variants across coding regions of 409 cancer genes and measured mRNA/miRNA expression in nine PNETs, eight PDACs, and four intestinal neuroendocrine tumors (INETs). There were 153 unique somatic variants considered pathogenic or likely pathogenic, found in 50, 57, and 24 genes in PDACs, PNETs, and INETs, respectively. Ten and 11 genes contained a pathogenic mutation in at least one sample of all tumor types and in PDACs and PNETs, respectively, while 28, 34, and 11 genes were found to be mutated exclusively in PDACs, PNETs, and INETs, respectively. The mRNA and miRNA transcriptomes of PDACs and NETs were distinct: from 54 to 1659 differentially expressed mRNAs and from 117 to 250 differentially expressed miRNAs exhibited high discrimination ability and resulted in models with an area under the receiver operating characteristics curve (AUC-ROC) >0.9 for both miRNA and mRNA. Given the miRNAs high stability, we proposed exploring that class of RNA as new pancreatic tumor biomarkers.

MicroRNA-127 inhibits cell proliferation via targeting Kif3b in pancreatic β cells

MicroRNAs (miRNAs) have been implicated in β cells dysfunction. Previous studies indicated that miR-127 was specifically abundant in β cells and one of its target genes, Kif3b, promoted cell proliferation. However, the impact of the miR-127-Kif3b axis on β cells remains unknown. In this study, we revealed that miR-127 level was declined both in islets from the mice with a high-fat diet and in MIN6 cells with elevated glucose treatment. The elevated level of miR-127 attenuated β cell proliferation by repressing Kif3b expression without affecting apoptosis and cell cycle, and it dampened insulin secretion. Moreover, β cell-derived miR-127 could also affect the islet endothelial cell-line, MS1, in vitro via the transfer of extracellular vesicles (EVs). Treating MS1 cells with the EVs secreted by MIN6 cells exhibited a higher ability in cell migration and tube formation. However, this effect was abolished by the miR-127 inhibitor co-cultured with EVs-treated MS1 cells. Thus, we define that miR-127 is a crucial regulator of insulin secretion and cell proliferation in pancreatic β cells as well as a potential functional regulation factor in islet endothelial cells.

Role of cancer stem cells in the development of giant cell tumor of bone

The primary bone tumor is usually observed in adolescence age group which has been shown to be part of nearly 20% of the sarcomas known today. Giant cell tumor of bone (GCTB) can be benign as well as malignant tumor which exhibits localized dynamism and is usually associated with the end point of a long bone. Giant cell tumor (GCT) involves mononuclear stromal cells which proliferate at a high rate, multinucleated giant cells and stromal cells are equally present in this type of tumor. Cancer stem cells (CSCs) have been confirmed to play a potential role in the development of GCT. Cancer stem cell-based microRNAs have been shown to contribute to a greater extent in giant cell tumor of bone. CSCs and microRNAs present in the tumors specifically are a great concern today which need in-depth knowledge as well as advanced techniques to treat the bone cancer effectively. In this review, we attempted to summarize the role played by cancer stem cells involving certain important molecules/factors such as; Mesenchymal Stem Cells (MSCs), miRNAs and signaling mechanism such as; mTOR/PI3K-AKT, towards the formation of giant cell tumor of bone, in order to get an insight regarding various effective strategies and research advancements to obtain adequate knowledge related to CSCs which may help to focus on highly effective treatment procedures for bone tumors.

Expression profiles of miRNAs in giant cell tumor of bone showed miR-187-5p and miR-1323 can regulate biological functions through inhibiting FRS2

Background

Giant cell tumor of bone (GCTB) is considered to be a kind of borderline tumor, which has a tendency to recur and translocate. MicroRNAs are one type of small noncoding RNA, which can inhibit the translation of targeted mRNA through RNA‐induced silencing complex.

Methods

Microarray was conducted on three groups of tumor tissues and normal tissues from patients with GCTB, and results showed different expression profiles of miRNAs with Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes analysis. The functions of miR‐187‐5p and miR‐1323, which were highly expressed in GCTB, were examined by 5‐ethynyl‐2′‐deoxyuridine (EDU), transwell, and CCK8 assays. RNAhybrid et al. (rna prediction softwares) predicted that the two microRNAs targeted fibroblast growth factor receptor substrate 2 (FRS2), which was verified by luciferase assay and rescue experiments.

Results

miR‐187‐5p and miR‐1323 were highly expressed in tumor tissues. They can jointly regulate the biological functions of GCTB in vitro. Luciferase assay confirmed that the two microRNAs can bind to the 3′ untranslated regions (UTR) of mRNA of FRS2. And, rescue experiments verified the relationships between the two microRNAs and FRS2.

Conclusion

There were some different‐expressed microRNAs between GCTB and normal tissues. miR‐187‐5p and miR‐1323 can regulate the biological functions of GCTB through influencing the expression of FRS2.

PDIA4: The basic characteristics, functions and its potential connection with cancer

Disulfide bond formation is catalyzed by the protein disulfide Isomerases (PDI) family. This is a critical step in protein folding which occurs within the endoplasmic reticulum. PDIA4, as a member of the PDI family, can cause the adjustment of αIIβ 3 affinities which activate platelet and promote thrombosis formation. Endoplasmic reticulum response is triggered by accumulation of abnormal folding proteins concomitant with increasing PDIA4 expression. Besides, current researches indicate that activated platelets and ERS response affect tumor progression. And PDIA4, as previous reported, also participates in tumor progression by affecting cell apoptosis and DNA repair machinery without specific mechanisms revealed.Therefore, PDI inhibitor might possess great potential value in against tumor progression. In this review, we summarize information on PDIA4 including its the basic characteristics and its implication on tumor.

MicroRNA-127 Inhibits the Progression of Melanoma by Downregulating Delta-Like Homologue 1

Objective

Melanoma is the most common form of skin cancer with low survival rate and poor prognosis. MicroRNAs (miRNAs) have been reported to play essential roles in progression of melanoma. However, the role and mechanism of miR-127 in the process of melanoma remain poorly understood.

Methods

The expressions of miR-127 and delta-like homologue 1 (DLK1) were measured in melanoma tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Cell proliferation and apoptosis were measured by MTT assay, flow cytometry, and Western blot. The interaction between miR-127 and DLK1 was investigated by bioinformatics analysis, luciferase activity assay, and RNA immunoprecipitation (RIP). Murine xenograft model was conducted to investigate the effect of miR-127 on tumor growth in vivo.

Results

miR-127 was inhibited and DLK1 mRNA was enhanced in melanoma tissues and cells. Low abundance of miR-127 in melanoma tissues predicted a poor prognosis and was associated with the malignant clinicopathological features. Overexpression of miR-127 inhibited cell proliferation and induced apoptosis in melanoma cells. Moreover, DLK1 was targeted by miR-127 and its restoration reversed the regulatory effect of miR-127 on the process of melanoma. Besides, the addition of miR-127 suppressed xenograft tumor growth via suppressing DLK1 protein level in nude mice.

Conclusion

miR-127 blocked the development of melanoma by targeting DLK1, providing a novel biomarker for the treatment of melanoma.

Tumor Suppressor Function of miR-127-3p and miR-376a-3p in Osteosarcoma Cells

Since the introduction of high-dose chemotherapy about 35 years ago, survival rates of osteosarcoma patients have not been significantly improved. New therapeutic strategies replacing or complementing conventional chemotherapy are therefore urgently required. MicroRNAs represent promising targets for such new therapies, as they are involved in the pathology of multiple types of cancer, and aberrant expression of several miRNAs has already been shown in osteosarcoma. In this study, we identified silencing of miR-127-3p and miR-376a-3p in osteosarcoma cell lines and tissues and investigated their role as potential tumor suppressors in vitro and in vivo. Transfection of osteosarcoma cells (n = 6) with miR-127-3p and miR-376a-3p mimics significantly inhibited proliferation and reduced the colony formation capacity of these cells. In contrast, we could not detect any influence of miRNA restoration on cell cycle and apoptosis induction. The effects of candidate miRNA restoration on tumor engraftment and growth in vivo were analyzed using a chicken chorioallantoic membrane (CAM) assay. Cells transfected with mir-127-3p and miR-376a-3p showed reduced tumor take rates and tumor volumes and a significant decrease of the cumulative tumor volumes to 41% and 54% compared to wildtype cells. The observed tumor suppressor function of both analyzed miRNAs indicates these miRNAs as potentially valuable targets for the development of new therapeutic strategies for the treatment of osteosarcoma.

MicroRNA-362-5p enhances the cisplatin sensitivity of gastric cancer cells by targeting suppressor of zeste 12 protein

Chemotherapy resistance is a major obstacle to the effective treatment of patients with gastric cancer (GC). Mounting evidence has indicated that the dysregulation of microRNAs (miRNAs) is associated with the sensitivity of cancer cells to chemotherapy. However, the mechanisms underlying miRNA-mediated chemoresistance in GC cells remain to be elucidated. The present study aimed to identify functional miRNAs that may regulate the sensitivity of human GC cells to cisplatin (DDP) treatment. miRNA microarray analysis was used to identify differentially expressed miRNAs between the human cisplatin-sensitive GC cell line SGC7901 and the corresponding cisplatin-resistant cell line SGC7901/DDP. miRNA (miR)-362-5p, which is associated with numerous types of tumors, was identified to be downregulated in the SGC7901/DDP cell line. However, the biological role of miR-362-5p in SGC7901/DDP cells remains to be explored. The expression level of miR-362-5p was demonstrated to be reduced in SGC7901/DDP cells compared with SGC7901 cells by reverse transcription-quantitative PCR. Upregulation of miR-362-5p significantly increased cisplatin sensitivity and cisplatin-induced apoptosis, whereas downregulation of miR-362-5p attenuated these effects. Databases predicted that suppressor of zeste 12 protein (SUZ12) may function as a target of miR-362-5p. In addition, the mRNA and protein expression levels of SUZ12 in SGC7901/DDP cells were significantly higher compared with SGC7901 cells and negatively associated with miR-362-5p expression. MTT and western blot analysis assays confirmed that knockdown of SUZ12 enhanced cisplatin sensitivity and decreased NF-κB/p65 protein levels in SGC7901/DDP cells. In addition, upregulation of miR-362-5p in SGC7901/DDP cells decreased the protein expression level of SUZ12, whereas downregulation of miR-362-5p increased the SUZ12 expression level. The results of the present study suggested that dysregulated miR-362-5p may target SUZ12 to promote the development of cisplatin resistance and attenuate cisplatin-induced apoptosis. Therefore, miR-362-5p upregulation combined with cisplatin treatment may serve as a promising therapeutic strategy for patients with cisplatin-resistant GC.

MicroRNA-127-3p controls murine hematopoietic stem cell maintenance by limiting differentiation

The balance between self-renewal and differentiation is crucial to ensure the homeostasis of the hematopoietic system, and is a hallmark of hematopoietic stem cells. However, the underlying molecular pathways, including the role of micro-RNA, are not completely understood. To assess the contribution of micro-RNA, we performed micro-RNA profiling of hematopoietic stem cells and their immediate downstream progeny multi-potent progenitors from wild-type control and Pbx1-conditional knockout mice, whose stem cells display a profound self-renewal defect. Unsupervised hierarchical cluster analysis separated stem cells from multi-potent progenitors, suggesting that micro-RNA might regulate the first transition step in the adult hematopoietic development. Notably, Pbx1-deficient and wild-type cells clustered separately, linking micro-RNAs to self-renewal impairment. Differential expression analysis of micro-RNA in the physiological stem cell-to-multi-potent progenitor transition and in Pbx1-deficient stem cells compared to control stem cells revealed miR-127-3p as the most differentially expressed. Furthermore, miR-127-3p was strongly stem cell-specific, being quickly down-regulated upon differentiation and not re-expressed further downstream in the bone marrow hematopoietic hierarchy. Inhibition of miR-127-3p function in Lineage-negative cells, achieved through a lentiviral-sponge vector, led to severe stem cell depletion, as assessed with serial transplantation assays. miR-127-3p-sponged stem cells displayed accelerated differentiation, which was uncoupled from proliferation, accounting for the observed stem cell reduction. miR-127-3p overexpression in Lineage-negative cells did not alter stem cell pool size, but gave rise to lymphopenia, likely due to lack of miR-127-3p physiological downregulation beyond the stem cell stage. Thus, tight regulation of miR-127-3p is crucial to preserve the self-renewing stem cell pool and homeostasis of the hematopoietic system.

Molecular and cellular mechanisms for zoledronic acid-loaded magnesium-strontium alloys to inhibit giant cell tumors of bone

Giant Cell Tumors of Bone (GCTB) are benign but aggressive and metastatic tumors. Surgical removal cannot eradicate GCTB due to the subsequent recurrence and osteolysis. Here we developed Zoledronic acid (ZA)-loaded magnesium-strontium (Mg-Sr) alloys that can inhibit GCTB and studied the molecular and cellular mechanisms of such inhibition. We first formed a calcium phosphate (CaP) coating on the Mg-1.5 wt%Sr implants by coprecipitation and then loaded ZA on the CaP coating. We examined the response of GCTB cells to the ZA-loaded alloys. At the cellular level, the alloys not only induced apoptosis and oxidative stress of GCTB cells, and suppressed their resultant pre-osteoclast recruitment, but also inhibited their migration. At the molecular level, the alloys could significantly activate the mitochondrial pathway and inhibit the NF-κB pathway in the GCTB cells. These collectively enable the ZA-loaded alloys to suppress GCTB cell growth and osteolysis, and thus improve our understanding of the materials-induced tumor inhibition. Our study shows that ZA-loaded alloys could be a potential implant in repairing the bone defects after tumor removal in GCTB therapy.

STATEMENT OF SIGNIFICANCE

In clinics, giant cell tumors of bone (GCTB) are removed by surgery. However, the resultant defects in bone still contain aggressive and metastatic GCTB cells that can recruit osteoclasts to damage bone, leading to new GCTB tumor growth and bone damage after tumor surgery. Hence, it is of high demand in developing a material that can not only fill the bone defects as an implant but also inhibit GCTB in the defect area as a therapeutic agent. More importantly, the molecular and cellular mechanism by which such a material inhibits GCTB growth has never been explored. To solve these two problems, we prepared a new biomaterial, the Mg-Sr alloys that were first coated with calcium phosphate and then loaded with a tumor-inhibiting molecule (Zoledronic acid, ZA). Then, by using a variety of molecular and cellular biological assays, we studied how the ZA-loaded alloys induced the death of GCTB cells (derived from patients) and inhibited their growth at the molecular and cellular level. At the cellular level, our results showed that ZA-loaded Mg-Sr alloys not only induced apoptosis and oxidative stress of GCTB cells, and suppressed their induced pre-osteoclast recruitment, but also inhibited their migration. At the molecular level, our data showed that ZA released from the ZA-loaded Mg-Sr alloys could significantly activate the mitochondrial pathway and inhibit the NF-κB pathway in the GCTB cells. Both mechanisms collectively induced GCTB cell death and inhibited GCTB cell growth. This work showed how a biomaterial inhibit tumor growth at the molecular and cellular level, increasing our understanding in the fundamental principle of materials-induced cancer therapy. This work will be interesting to readers in the fields of metallic materials, inorganic materials, biomaterials and cancer therapy.

miR-376a inhibits breast cancer cell progression by targeting neuropilin-1 NR

Background

The roles and related mechanism of miR-376a in breast cancer cell progression are unclear.

Methods

Kaplan-Meier plotter analysis was used to analyze the correlation between miR-376a and the overall survival (OS) of breast cancer patients. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to detect miR-376a level in breast cancer cells. Cell viability, transwell migration and invasion, and cell apoptosis were constructed to investigate the effects of miR-376a on breast cancer cells. Luciferase reporter and RNA immunoprecipitation (RIP) were used to explore the targeting of miR-376a on NRP-1.

Results

miR-376a expression was positively correlated with the overall survival of breast cancer patients, and significantly decreased in breast cancer cells. Functionally, miR-376a over-expression suppressed cell proliferation, migration and invasion, and promoted cells apoptosis. Additionally, miR-376a could directly target NRP-1 and exerted its effect through NRP-1.

Conclusion

miR-376a could suppress breast cancer cell progression via directly targeting NRP-1.

Intraductal papillary mucinous neoplasm of the pancreas rapidly xenografts in chicken eggs and predicts aggressiveness

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas has a high risk of progressing to invasive pancreatic ductal adenocarcinoma (PDA), but experimental models for IPMN are largely missing. New experimental systems for the molecular characterization of IPMN and for personalized prognosis and treatment options for IPMN are urgently needed. We analyzed the potential use of fertilized chicken eggs for the culture of freshly resected IPMN tissue. We transplanted 49 freshly resected IPMN tissues into eggs and compared the growth characteristics to IPMN tissues transplanted into mice; this was followed by an analysis of histology, morphology, and marker expression. Of the IPMN tissues transplanted into eggs, 63% formed tumor xenografts within 4 days, while none of the 12 IPMN tissues transplanted into immunodeficient mice engrafted. In the eggs, the grafting efficiency of high-grade (n = 14) and intermediate-grade (n = 17) dysplasia was 77% and was significantly higher than the 39% grafting efficiency of low-grade dysplasia (n = 18). According to mucinous expression, 46 IPMN tissues were classified into gastric (n = 6), intestinal (n = 3), oncocytic (n = 23), and pancreatobiliary (n = 14) subtypes. The grafting efficiency was highest for the pancreatobiliary subtype (86%), followed by the oncocytic (70%), gastric (33%) and intestinal (33%) subtypes. The morphology and expression patterns of mucins, progression markers and pancreatic ductal markers were comparable between the primary IPMN tissues and their xenograft copies. The individual tumor environment was largely maintained during subtransplantation, as evaluated upon passage 6. This new IPMN model may facilitate experimental studies and treatment decisions for the optimal personalized management of IPMN.

MicroRNA-191-5p exerts a tumor suppressive role in renal cell carcinoma

Renal cell carcinoma (RCC) is a common tumor of the urinary system. Previously, miR-191-5p has been reported to be associated with various types of cancer; however, its specific functions in RCC have not been investigated to date. In the present study, the expression of miR-191-5p in the 786-O and ACHN cell lines was detected in vitro by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results of RT-qPCR revealed that miR-191-5p was significantly downregulated in the two cell lines compared with the 293T cell line. miR-191-5p was also significantly downregulated in RCC tissue compared with paired normal tissue. In addition, the effects of miR-191-5p on cell proliferation, migration, invasion and apoptosis were examined by CCK-8, MTT, wound scratch, Transwell and flow cytometry assays. Downregulation of miR-191-5p was observed to promote cell proliferation, migration and invasion, as well as to repress the cell apoptosis of 786-O and ACHN cells. Therefore, the current study suggests that miR-191-5p functions as a tumor suppressor in RCC. Further studies are required to uncover the underlying signaling pathway of miR-191-5p and its potential role as a biomarker for early detection and prognosis prediction, and as a therapeutic target of RCC.