miR-509-3p is clinically significant and strongly attenuates cellular migration and multi-cellular spheroids in ovarian cancer

The downregulation of miR-509-3p expression by collagen type XI alpha 1-regulated hypermethylation facilitates cancer progression and chemoresistance via the DNA methyltransferase 1/Small ubiquitin-like modifier-3 axis in ovarian cancer cells

BACKGROUND

MicroRNAs are a group of small non-coding RNAs that are involved in development and diseases such as cancer. Previously, we demonstrated that miR-335 is crucial for preventing collagen type XI alpha 1 (COL11A1)-mediated epithelial ovarian cancer (EOC) progression and chemoresistance. Here, we examined the role of miR-509-3p in EOC.

METHODS

The patients with EOC who underwent primary cytoreductive surgery and postoperative platinum-based chemotherapy were recruited. Their clinic-pathologic characteristics were collected, and disease-related survivals were determined. The COL11A1 and miR-509-3p mRNA expression levels of 161 ovarian tumors were determined by real-time reverse transcription-polymerase chain reaction. Additionally, miR-509-3p hypermethylation was evaluated by sequencing in these tumors. The A2780CP70 and OVCAR-8 cells transfected with miR-509-3p mimic, while the A2780 and OVCAR-3 cells transfected with miR-509-3p inhibitor. The A2780CP70 cells transfected with a small interference RNA of COL11A1, and the A2780 cells transfected with a COL11A1 expression plasmid. Site-directed mutagenesis, luciferase, and chromatin immunoprecipitation assays were performed in this study.

RESULTS

Low miR-509-3p levels were correlated with disease progression, a poor survival, and high COL11A1 expression levels. In vivo studies reinforced these findings and indicated that the occurrence of invasive EOC cell phenotypes and resistance to cisplatin are decreased by miR-509-3p. The miR-509-3p promoter region (p278) is important for miR-509-3p transcription regulation via methylation. The miR-509-3p hypermethylation frequency was significantly higher in EOC tumors with a low miR-509-3p expression than in those with a high miR-509-3p expression. The patients with miR-509-3p hypermethylation had a significantly shorter overall survival (OS) than those without miR-509-3p hypermethylation. Mechanistic studies further indicated that miR-509-3p transcription was downregulated by COL11A1 through a DNA methyltransferase 1 (DNMT1) stability increase. Moreover, miR-509-3p targets small ubiquitin-like modifier (SUMO)-3 to regulate EOC cell growth, invasiveness, and chemosensitivity.

CONCLUSION

The miR-509-3p/DNMT1/SUMO-3 axis may be an ovarian cancer treatment target.

Human placental microRNAs dysregulated by cadmium exposure predict neurobehavioral outcomes at birth

BACKGROUND

Prenatal cadmium (Cd) exposure has been implicated in both placental toxicity and adverse neurobehavioral outcomes. Placental microRNAs (miRNAs) may function to developmentally program adverse pregnancy and newborn health outcomes in response to gestational Cd exposure.

METHODS

In a subset of the Rhode Island Child Health Study (RICHS, n = 115) and the New Hampshire Birth Cohort Study (NHBCS, = 281), we used small RNA sequencing and trace metal analysis to identify Cd-associated expression of placental miRNAs using negative binomial generalized linear models. We predicted mRNAs targeted by Cd-associated miRNAs and relate them to neurobehavioral outcomes at birth through the integration of transcriptomic data and summary scores from the NICU Network Neurobehavioral Scale (NNNS).

RESULTS

Placental Cd concentrations are significantly associated with the expression level of five placental miRNAs in NHBCS, with similar effect sizes in RICHS. These miRNA target genes overrepresented in nervous system development, and their expression is correlated with NNNS metrics suggestive of atypical neurobehavioral outcomes at birth.

CONCLUSIONS

Gestational Cd exposure is associated with the expression of placental miRNAs. Predicted targets of these miRNAs are involved in nervous system development and may also regulate placental physiology, allowing their dysregulation to modify developmental programming of early life health outcomes.

IMPACT

This research aims to address the poor understanding of the molecular mechanisms governing adverse pregnancy and newborn health outcomes in response to Gestational cadmium (Cd) exposure. Our results outline a robust relationship between Cd-associated placental microRNA expression and NICU Network Neurobehavioral Scales (NNNS) at birth indicative of atypical neurobehavior. This study utilized healthy mother-infant cohorts to describe the role of Cd-associated dysregulation of placental microRNAs as a potential mechanism by which adverse neurobehavioral outcomes are developmentally programmed.

The Downregulation of miR-509-3p Expression by Collagen Type XI Alpha 1-Regulated Hypermethylation Facilitates Cancer Progression and Chemoresistance via the DNA Methyltransferase 1/Small Ubiquitin-like Modifier-3 Axis in Ovarian Cancer Cells

Background MicroRNAs are a group of small non-coding RNAs that are involved in development and diseases such as cancer. Previously, we demonstrated that miR-335 is crucial for preventing collagen type XI alpha 1 (COL11A1)-mediated epithelial ovarian cancer (EOC) progression and chemoresistance. Here, we examined the role of miR-509-3p in EOC. Methods The patients with EOC who underwent primary cytoreductive surgery and postoperative platinum-based chemotherapy were recruited. Their clinic-pathologic characteristics were collected, and disease-related survivals were determined. The COL11A1 and miR-509-3p mRNA expression levels of 161 ovarian tumors were determined by real-time reverse transcription-polymerase chain reaction. Additionally, miR-509-3p hypermethylation was evaluated by sequencing in these tumors. The A2780CP70 and OVCAR-8 cells transfected with miR-509-3p mimic, while the A2780 and OVCAR-3 cells transfected with miR-509-3p inhibitor. The A2780CP70 cells transfected with a small interference RNA of COL11A1, and the A2780 cells transfected with a COL11A1 expression plasmid. Site-directed mutagenesis, luciferase, and chromatin immunoprecipitation assays were performed in this study. Results Low miR-509-3p levels were correlated with disease progression, a poor survival, and high COL11A1 expression levels. In vivo studies reinforced these findings and indicated that the occurrence of invasive EOC cell phenotypes and resistance to cisplatin are decreased by miR-509-3p. The miR-509-3p promoter region (p278) is important for miR-509-3p transcription regulation via methylation. The miR-509-3p hypermethylation frequency was significantly higher in EOC tumors with a low miR-509-3p expression than in those with a high miR-509-3p expression. The patients with miR-509-3p hypermethylation had a significantly shorter overall survival (OS) than those without miR-509-3p hypermethylation. Mechanistic studies further indicated that miR-509-3p transcription was downregulated by COL11A1 through a DNA methyltransferase 1 (DNMT1) phosphorylation and stability increase. Moreover, miR-509-3p targets small ubiquitin-like modifier (SUMO)-3 to regulate EOC cell growth, invasiveness, and chemosensitivity. Conclusion The miR-509-3p/DNMT1/SUMO-3 axis may be an ovarian cancer treatment target.

Extracellular Matrix in High-Grade Serous Ovarian Cancer: Advances in Understanding of Carcinogenesis and Cancer Biology

High-grade serous ovarian cancer (HGSOC) is notoriously known as the "silent killer" of post-menopausal women as it has an insidious progression and is the deadliest gynaecological cancer. Although a dual origin of HGSOC is now widely accepted, there is growing evidence that most cases of HGSOC originate from the fallopian tube epithelium. In this review, we will address the fallopian tube origin and involvement of the extracellular matrix (ECM) in HGSOC development. There is limited research on the role of ECM at the earliest stages of HGSOC carcinogenesis. Here we aim to synthesise current understanding on the contribution of ECM to each stage of HGSOC development and progression, beginning at serous tubal intraepithelial carcinoma (STIC) precursor lesions and proceeding across key events including dissemination of tumourigenic fallopian tube epithelial cells to the ovary, survival of these cells in peritoneal fluid as multicellular aggregates, and colonisation of the ovary. Likewise, as part of the metastatic series of events, serous ovarian cancer cells survive travel in peritoneal fluid, attach to, migrate across the mesothelium and invade into the sub-mesothelial matrix of secondary sites in the peritoneal cavity. Halting cancer at the pre-metastatic stage and finding ways to stop the dissemination of ovarian cancer cells from the primary site is critical for improving patient survival. The development of drug resistance also contributes to poor survival statistics in HGSOC. In this review, we provide an update on the involvement of the ECM in metastasis and drug resistance in HGSOC. Interplay between different cell-types, growth factor gradients as well as evolving ECM composition and organisation, creates microenvironment conditions that promote metastatic progression and drug resistance of ovarian cancer cells. By understanding ECM involvement in the carcinogenesis and chemoresistance of HGSOC, this may prompt ideas for further research for developing new early diagnostic tests and therapeutic strategies for HGSOC with the end goal of improving patient health outcomes.

Hsa_circ_0005273 acts as a sponge of miR-509-3p to promote the malignant behaviors of breast cancer by regulating HMMR expression

BACKGROUND

Breast cancer (BC) is a common malignant tumor that threatens the health of women worldwide. Hsa_circ_0005273 has been identified as a carcinogenic factor in some solid tumors, including BC. However, the molecular mechanism of circ_0005273 in BC is poorly defined.

METHODS

The expression of circ_0005273, miR-509-3p, and hyaluronan-mediated motility receptor (HMMR) mRNA in BC was detected by quantitative real-time polymerase chain reaction. Cell proliferation, migration, invasion, and apoptosis were detected by 5-ethynyl-2'-deoxyuridine, transwell, and flow cytometry assays. The glycolysis level was detected via specific kits. Western blot was used to detect protein expression. Binding between miR-509-3p and circ_0005273 or HMMR was also verified by dual-luciferase reporter, RNA pull-down, and RNA immunoprecipitation assays. Xenograft tumor model was used to detect tumor changes in mice, and immunohistochemistry assay was employed to detect Ki-67 abundance.

RESULTS

Circ_0005273 was increased in BC tissues and cells. Circ_0005273 knockdown might inhibit BC cell proliferation, migration, invasion, glutamine metabolism, and induce apoptosis. Circ_0005273 was a miR-509-3p, and the repression role of circ_0005273 absence on BC cell development was weakened by miR-509-3p inhibitor or HMMR overexpression. Circ_0005273 up-regulated the expression of HMMR by sponging miR-509-3p. Additionally, circ_0005273 silencing might hinder tumor growth in vivo.

CONCLUSION

Circ_0005273 knockdown might repress BC cell malignant behaviors by regulating the miR-509-3p/HMMR axis, which might provide a potential therapeutic target for BC.

The inter- and multi- generational epigenetic alterations induced by maternal cadmium exposure

Exposure to cadmium during pregnancy, from environmental or lifestyle factors, has been shown to have detrimental fetal and placental developmental effects, along with negatively impacting maternal health during gestation. Additionally, prenatal cadmium exposure places the offspring at risk for developing diseases in infancy, adolescence, and adulthood. Although given much attention, the underlying mechanisms of cadmium-induced teratogenicity and disease development remain largely unknown. Epigenetic changes in DNA, RNA and protein modifications have been observed during cadmium exposure, which implies a scientific premise as a conceivable mode of cadmium toxicity for developmental origins of health and disease (DOHaD). This review aims to examine the literature and provide a comprehensive overview of epigenetic alterations induced by prenatal cadmium exposure, within the developing fetus and placenta, and the continued effects observed in childhood and across generations.

Three-dimensional in vitro culture models in oncology research

Cancer is a multifactorial disease that is responsible for 10 million deaths per year. The intra- and inter-heterogeneity of malignant tumors make it difficult to develop single targeted approaches. Similarly, their diversity requires various models to investigate the mechanisms involved in cancer initiation, progression, drug resistance and recurrence. Of the in vitro cell-based models, monolayer adherent (also known as 2D culture) cell cultures have been used for the longest time. However, it appears that they are often less appropriate than the three-dimensional (3D) cell culture approach for mimicking the biological behavior of tumor cells, in particular the mechanisms leading to therapeutic escape and drug resistance. Multicellular tumor spheroids are widely used to study cancers in 3D, and can be generated by a multiplicity of techniques, such as liquid-based and scaffold-based 3D cultures, microfluidics and bioprinting. Organoids are more complex 3D models than multicellular tumor spheroids because they are generated from stem cells isolated from patients and are considered as powerful tools to reproduce the disease development in vitro. The present review provides an overview of the various 3D culture models that have been set up to study cancer development and drug response. The advantages of 3D models compared to 2D cell cultures, the limitations, and the fields of application of these models and their techniques of production are also discussed.

MiR-509-3p is oncogenic, targets the tumor suppressor PHLPP2, and functions as a novel tumor adjacent normal tissue based prognostic biomarker in colorectal cancer

Background

Recently the role of microRNAs has been explored immensely as novel regulators and potential biomarkers in several cancers. MiR-509-3p is one such miRNA that has been observed to show a mixed expression in different cancers, while it’s expression and clinical relevance in colorectal cancer (CRC) has not yet been characterized.

Methods

We used quantitative PCR to evaluate the expression of miR-509-3p in fresh-frozen CRC tumor tissues and the corresponding tumor-adjacent normal (NAT) tissues from 103 patients. Subsequently, functional studies were performed to further interpret the role of the miRNA in CRC.

Results

MiR-509-3p was found to be overexpressed in CRC tissues in nearly 80% of cases and was associated with an aggressive disease presentation. Notably, a higher expression of the miRNA promoted cell proliferation, migration, and invasion of CRC cells in in vitro and in vivo models. Mechanistically, we confirmed that miR-509-3p directly binds the 3’UTR of the tumor suppressor PHLPP2 and inhibits its expression. Furthermore, within the previous 103 clinical tissue specimens, we observed an overexpression of miR-509-3p within the NAT tissue of patients associated with a poor disease prognosis. Using multivariate analysis, it was observed that the expression of miR-509-3p within the NAT tissue was an independent predictor of prognosis in CRC. At the cellular level, through indirect coculture experiments, miR-509-3p was observed to regulate the proliferative, migratory, and invasive behavior of normal colon cells.

Conclusion

MiR-509-3p strongly contributes to the development and progression of CRC and can potentially function as a prognostic biomarker in the disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-09075-x.

SF3B4 promotes ovarian cancer progression by regulating alternative splicing of RAD52

Many studies have proven that splicing factors are crucial for human malignant tumor development. However, as a classical splicing factor, the expression of SF3B4 is not clear, and its biological function needs to be further clarified in ovarian cancer (OC). We determined that SF3B4 was obviously upregulated and its high expression was associated with poor prognosis in OC patients. In vitro and in vivo assays suggested that SF3B4 overexpression promoted OC cell proliferation and mobility, and downregulation of SF3B4 had the opposite effect. Further studies found that miR-509–3p decreased SF3B4 mRNA expression by binding to the 3’ -UTR of SF3B4 directly. Importantly, we revealed that RAD52 was a potential target of SF3B4 through alternative splicing events analysis. Loss of SF3B4 led to decreased expression of RAD52, owing to intron 8 retention and generation of premature termination codons. Moreover, decreased expression of RAD52 partially counteracted the tumor-promoting effect of SF3B4 overexpression. In conclusion, our results suggested that SF3B4, negatively regulated by miR-509–3p, promoted OC progression through effective splicing of RAD52. Therefore, SF3B4 may be a promising biomarker and effective therapeutic target for OC.

MicroRNA Alterations Induced in Human Skin by Diesel Fumes, Ozone, and UV Radiation

Epigenetic alterations are a driving force of the carcinogenesis process. MicroRNAs play a role in silencing mutated oncogenes, thus defending the cell against the adverse consequences of genotoxic damages induced by environmental pollutants. These processes have been well investigated in lungs; however, although skin is directly exposed to a great variety of environmental pollutants, more research is needed to better understand the effect on cutaneous tissue. Therefore, we investigated microRNA alteration in human skin biopsies exposed to diesel fumes, ozone, and UV light for over 24 h of exposure. UV and ozone-induced microRNA alteration right after exposure, while the peak of their deregulations induced by diesel fumes was reached only at the end of the 24 h. Diesel fumes mainly altered microRNAs involved in the carcinogenesis process, ozone in apoptosis, and UV in DNA repair. Accordingly, each tested pollutant induced a specific pattern of microRNA alteration in skin related to the intrinsic mechanisms activated by the specific pollutant. These alterations, over a short time basis, reflect adaptive events aimed at defending the tissue against damages. Conversely, whenever environmental exposure lasts for a long time, the irreversible alteration of the microRNA machinery results in epigenetic damage contributing to the pathogenesis of inflammation, dysplasia, and cancer induced by environmental pollutants.

MiR-509-3-5p inhibits colon cancer malignancy by suppressing GTSE1

BACKGROUND

The overarching goal of this research was to identify the effect of miR-509-3-5p on colon cancer (CC) and its interaction with potential target gene GTSE1 in CC.

METHODS

The miR-509-3-5p expression was ascertained after performing qRT-PCR analyses, and the ability of GTSE1 to influence this microRNA was detected after carrying out RNA pull-down assay. CCK-8 assay kit was first employed to determine the proliferation of the cells. To examine the migration and invasion level of HCT116 and SW480 cells, cell wound healing and transwell assay were later performed. After constructing luciferase reporter plasmids, luciferase reporter assay was used to confirm the impacts of miR-509-3-5p on GTSE1 in HCT116 and SW480 cells.

RESULTS

We found that miR-509-3-5p expression reduced in CC, and its overexpression inhibited the proliferation, migration and invasion of CC cells. We later discovered that miR-509-3-5p could target GTSE1 that was then proved to be an oncogene in CC.

CONCLUSION

Our study uncovered that miR-509-3-5p regulated CC malignancy by suppressing target gene GTSE1.

LncRNA HOXA-AS2 promotes the progression of prostate cancer via targeting miR-509-3p/PBX3 axis

Long non-coding RNAs (lncRNAs) act as crucial modulators during the development of diverse cancers. Although various types of lncRNAs in prostate cancer (PCa) have been explored, quantities of lncRNAs still wait to be exploited. The present study is to probe the functions and mechanism of lncRNA HOXA cluster antisense RNA 2 (HOXA-AS2) in PCa. In the present study, we discovered that HOXA-AS2 was highly expressed in PCa tissues and cells. HOXA-AS2 depletion obviously influenced cell proliferation, migration, invasion, as well as epithelial-to-mesenchymal transition (EMT) progression. In addition, miR-509-3p had low expression in PCa cells and inversely modulated by HOXA-AS2. Cutting down HOXA-AS2 expression was capable of up-regulating miR-509-3p expression. In addition, HOXA-AS2 served as a competing endogenous RNA (ceRNA) through sponging miR-509-3p to release pre-B-cell leukemia homeobox 3 (PBX3) expression. The expression of PBX3 was noticeably high in tumor tissues. And PBX3 expression level was down-regulated markedly with the knockdown of HOXA-AS2. Rescue experiments certified the facilitated role of HOXA-AS2-miR-509-3p-PBX3 axis in regulating the progress of PCa. The present study may provide clues for exploration of novel therapeutic targets for PCa patients.

MicroRNAs Regulating Hippo-YAP Signaling in Liver Cancer

Liver cancer is one of the most common cancers worldwide, and its prevalence and mortality rate are increasing due to the lack of biomarkers and effective treatments. The Hippo signaling pathway has long been known to control liver size, and genetic depletion of Hippo kinases leads to liver cancer in mice through activation of the downstream effectors yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ). Both YAP and TAZ not only reprogram tumor cells but also alter the tumor microenvironment to exert carcinogenic effects. Therefore, understanding the mechanisms of YAP/TAZ-mediated liver tumorigenesis will help overcome liver cancer. For decades, small noncoding RNAs, microRNAs (miRNAs), have been reported to play critical roles in the pathogenesis of many cancers, including liver cancer. However, the interactions between miRNAs and Hippo-YAP/TAZ signaling in the liver are still largely unknown. Here, we review miRNAs that influence the proliferation, migration and apoptosis of tumor cells by modulating Hippo-YAP/TAZ signaling during hepatic tumorigenesis. Previous findings suggest that these miRNAs are potential biomarkers and therapeutic targets for the diagnosis, prognosis, and treatment of liver cancer.

Bioink: a 3D-bioprinting tool for anticancer drug discovery and cancer management

'Bioinks' are important tools for the fabrication of artificial living-tissue constructs that are able to mimic all properties of native tissues via 3D bioprinting technologies. Bioinks are most commonly made by incorporating live cells of interest within a natural or synthetic biocompatible polymeric matrix. In oncology research, the ability to recreate a tumor microenvironment (TME) using by 3D bioprinting constitutes a promising approach for drug development, screening, and in vitro cancer modeling. Here, we review the different types of bioink used for 3D bioprinting, with a focus on its application in cancer management. In addition, we consider the fabrication of bioink using customized materials/cells and their properties in the field of cancer drug discovery.

Stiffness increases with myofibroblast content and collagen density in mesenchymal high grade serous ovarian cancer

Women diagnosed with high-grade serous ovarian cancers (HGSOC) are still likely to exhibit a bad prognosis, particularly when suffering from HGSOC of the Mesenchymal molecular subtype (50% cases). These tumors show a desmoplastic reaction with accumulation of extracellular matrix proteins and high content of cancer-associated fibroblasts. Using patient-derived xenograft mouse models of Mesenchymal and Non-Mesenchymal HGSOC, we show here that HGSOC exhibit distinct stiffness depending on their molecular subtype. Indeed, tumor stiffness strongly correlates with tumor growth in Mesenchymal HGSOC, while Non-Mesenchymal tumors remain soft. Moreover, we observe that tumor stiffening is associated with high stromal content, collagen network remodeling, and MAPK/MEK pathway activation. Furthermore, tumor stiffness accompanies a glycolytic metabolic switch in the epithelial compartment, as expected based on Warburg's effect, but also in stromal cells. This effect is restricted to the central part of stiff Mesenchymal tumors. Indeed, stiff Mesenchymal tumors remain softer at the periphery than at the core, with stromal cells secreting high levels of collagens and showing an OXPHOS metabolism. Thus, our study suggests that tumor stiffness could be at the crossroad of three major processes, i.e. matrix remodeling, MEK activation and stromal metabolic switch that might explain at least in part Mesenchymal HGSOC aggressiveness.

Transcriptomic analysis reveals tumor stage- or grade-dependent expression of miRNAs in serous ovarian cancer

Ovarian cancer (OC) is the most lethal gynecological malignancy and cellular mechanisms regulating OC progression are not completely understood. miRNAs are involved in many signaling pathways which are critical for the progression of malignant tumors, including OC. In the present study, we aim to identify miRNAs whose expression change in a tumor stage- and/or grade-dependent manner in serous OC. Computational analysis was performed in R using The Cancer Genome Atlas miRNA dataset. Kaplan-Meier plots were constructed to compare the survival of patients with low and high expressions of identified miRNAs. We found that 91 and 90 miRNAs out of 799 are differentially expressed in terms of tumor stage and grade, respectively. miR-152, miR-375 and miR-204 were top three hits in terms of tumor stage; and similarly, miR-125b, miR-768-5p and -3p in terms of tumor grade. Among top 15 miRNAs whose expression most significantly changed between tumor stages, 66.7% were upregulated in late stage. However, 53.3% of top 15 miRNAs identified in terms of tumor grade were upregulated in high grade. 11 miRNAs are differentially expressed in terms of both tumor stage and grade. Expression changes of some of the top miRNAs were found to be associated with shorter survival in serous OC. Text mining analysis showed that most of these miRNAs have not been previously studied in the context of OC. Mechanistic studies of these miRNAs in OC progression, differentiation and metastasis will be of high importance to develop novel strategies for the treatment of serous ovarian cancer.

Expression of the chrXq27.3 miRNA cluster in recurrent ovarian clear cell carcinoma and its impact on cisplatin resistance

Ovarian clear cell carcinoma (OCCC) is a histological subtype of epithelial ovarian cancer and exhibits dismal prognosis due to chemoresistance. Moreover, only few effective therapeutic options exist for patients with recurrent OCCC, and an understanding of its molecular characteristics is essential for the development of novel therapeutic approaches. In the present study, we investigated unique MicroRNAs (miRNA) profiles in recurrent/metastatic OCCC and the role of miRNAs in cisplatin resistance. Comprehensive miRNA sequencing revealed that expression of several miRNAs, including miR-508-3p, miR-509-3p, miR-509-3-5p, and miR-514a-3p was remarkably less in recurrent cancer tissues when compared with that in paired primary cancer tissues. These miRNAs are located in the chrXq27.3 region on the genome. Moreover, its expression was negative in omental metastases in two patients with advanced OCCC. In vitro analyses revealed that overexpression of miR-509-3p and miR-509-3-5p reversed cisplatin resistance and yes-associated protein 1 (YAP1) was partially responsible for the resistance. Immunohistochemistry revealed that YAP1 expression was inversely correlated with the chrXq27.3 miRNA cluster expression. In conclusion, these findings suggest that alteration of the chrXq27.3 miRNA cluster could play a critical role in chemoresistance and miRNAs in the cluster and their target genes can be potential therapeutic targets.

LncRNAs in Ovarian Cancer Progression, Metastasis, and Main Pathways: ceRNA and Alternative Mechanisms

Ovarian cancer (OvCa) develops asymptomatically until it reaches the advanced stages with metastasis, chemoresistance, and poor prognosis. Our review focuses on the analysis of regulatory long non-coding RNAs (lncRNAs) competing with protein-coding mRNAs for binding to miRNAs according to the model of competitive endogenous RNA (ceRNA) in OvCa. Analysis of publications showed that most lncRNAs acting as ceRNAs participate in OvCa progression: migration, invasion, epithelial-mesenchymal transition (EMT), and metastasis. More than 30 lncRNAs turned out to be predictors of survival and/or response to therapy in patients with OvCa. For a number of oncogenic (CCAT1, HOTAIR, NEAT1, and TUG1 among others) and some suppressive lncRNAs, several lncRNA/miRNA/mRNA axes were identified, which revealed various functions for each of them. Our review also considers examples of alternative mechanisms of actions for lncRNAs besides being ceRNAs, including binding directly to mRNA or protein, and some of them (DANCR, GAS5, MALAT1, and UCA1 among others) act by both mechanisms depending on the target protein. A systematic analysis based on the data from literature and Panther or KEGG (Kyoto Encyclopedia of Genes and Genomes) databases showed that a significant part of lncRNAs affects the key pathways involved in OvCa metastasis, EMT, and chemoresistance.

The Role of microRNAs in Epithelial Ovarian Cancer Metastasis

Epithelial ovarian cancer (EOC) is the deadliest gynecological cancer, and the major cause of death is mainly attributed to metastasis. MicroRNAs (miRNAs) are a group of small non-coding RNAs that exert important regulatory functions in many biological processes through their effects on regulating gene expression. In most cases, miRNAs interact with the 3′ UTRs of target mRNAs to induce their degradation and suppress their translation. Aberrant expression of miRNAs has been detected in EOC tumors and/or the biological fluids of EOC patients. Such dysregulation occurs as the result of alterations in DNA copy numbers, epigenetic regulation, and miRNA biogenesis. Many studies have demonstrated that miRNAs can promote or suppress events related to EOC metastasis, such as cell migration, invasion, epithelial-to-mesenchymal transition, and interaction with the tumor microenvironment. In this review, we provide a brief overview of miRNA biogenesis and highlight some key events and regulations related to EOC metastasis. We summarize current knowledge on how miRNAs are dysregulated, focusing on those that have been reported to regulate metastasis. Furthermore, we discuss the role of miRNAs in promoting and inhibiting EOC metastasis. Finally, we point out some limitations of current findings and suggest future research directions in the field.

Circulating and Tissue microRNAs as Biomarkers for Ovarian Cancer Prognosis

Ovarian cancer (OC) is one of the most common cancers globally with a high rate of cancer- associated mortality. OC may be classified into epithelial cell neoplasms, germ cell neoplasms and stromal cell neoplasms. The five-year survival in the early and advanced stages of disease is approximately 90% and 15%, respectively. microRNAs are short, single-stranded, non-coding ribonucleic acid (RNA). miRNAs play critical roles in post transcriptionally regulations of gene expression. miRNAs are found in different tissues and body fluids. In carcinogenesis the expression of miRNAs are altered. Recent studies have revealed that there is a relationship between alteration of miRNAs expression and the prognosis of patients with OC. The aim of this review was to summarize the findings of recent studies that have investigated the expression of circulating and tissue miRNAs as novel biomarkers in the prognosis of OC.

Three-Dimensional Cell Culture Based on Magnetic Fields to Assemble Low-Grade Ovarian Carcinoma Cell Aggregates Containing Lymphocytes

There is a limited number of established ovarian cancer cell lines matching the low-grade serous histotype available for research purposes. Three-dimensional (3D) culture systems provide in vitro models with better tissue-like characteristics than two-dimensional (2D) systems. The goal in the study was to characterize the growth of a given low-grade serous ovarian carcinoma cell line in a 3D culture system conducted in a magnetic field. Moreover, the culture system was evaluated in respect to the assembly of malignant cell aggregates containing lymphocytes. CAISMOV24 cell line alone or mixed with human peripheral blood mononuclear cells (PBMC) were cultured using a commercially available 3D culture system designed for 24 well plates. Resulting cell aggregates revealed the intrinsic capacity of CAISMOV24 cells to assemble structures morphologically defined as papillary, and reflected molecular characteristics usually found in ovarian carcinomas. The contents of lymphocytes into co-cultured cell aggregates were significantly higher (p < 0.05) when NanoShuttle-conjugated PBMC were employed compared with non-conjugated PBMC. Moreover, lymphocyte subsets NK, T-CD4, T-CD8 and T-regulatory were successfully retrieved from co-cultured cell aggregates at 72h. Thus, the culture system allowed CAISMOV24 cell line to develop papillary-like cell aggregates containing lymphocytes.

MicroRNA-509-3p inhibits cellular migration, invasion, and proliferation, and sensitizes osteosarcoma to cisplatin

Osteosarcoma (OS) is the most common primary pediatric malignancy of the bone having poor prognosis and long-term survival rates of less than 30% in patients with metastasis. MicroRNA-509 was reported to be downregulated in OS. We and others previously published that miR-509-3p can strongly attenuate cellular migration/invasion and sensitize ovarian cancer to cisplatin. Here, we show that overexpression of miR-509-3p inhibited migration of primary OS cell lines U2OS, HOS, and SaOS2 as well as metastatic derivatives 143B and LM7. miR-509-3p overexpression also inhibited proliferation and invasion of HOS and 143B cells and sensitized cells to cisplatin. Luciferase reporter assays using 3'-UTRs of predicted miR-509-3p targets associated with metastatic phenotypes revealed ARHGAP1 could be one of the downstream effectors of miR-509-3p in HOS. To find the global impact of miR-509-3p overexpression and cisplatin treatment we performed Reverse Phase Protein Analysis (RPPA). AXL, which has been reported to play a critical role in cisplatin resistance and confirmed as direct target of miR-509-3p was downregulated upon miR-509-3p treatment and further down-regulated upon miR-509-3p + cisplatin treatment. We propose that the miR-509-3p/AXL and miR-509-3p/ARHGAP1 axes have the potential to uncover new druggable targets for the treatment of drug resistant metastatic osteosarcoma.

Cluster miRNAs and cancer: Diagnostic, prognostic and therapeutic opportunities

MiRNAs are class of noncoding RNA important for gene expression regulation in many plants, animals and viruses. MiRNA clusters contain a set of two or more miRNA encoding genes, transcribed together as polycistronic miRNAs. Currently, there are approximately 159 miRNA clusters reported in the human genome consisting of miRNAs ranging from two or more miRNA genes. A large proportion of clustered miRNAs resides in and around the fragile sites or cancer associated genomic hotspots and plays an important role in carcinogenesis. Altered expression of miRNA cluster can be pro-tumorigenic or anti-tumorigenic and can be targeted for clinical management of cancer. Over the past few years, manipulation of miRNA clusters expression is attempted for experimental purpose as well as for diagnostic, prognostic and therapeutic applications in cancer. Re-expression of miRNAs by epigenetic therapy, genome editing such as clustered regulatory interspaced short palindromic repeats (CRISPR) and miRNA mowers showed promising results in cancer therapy. In this review, we focused on the potential of miRNA clusters as a biomarker for diagnosis, prognosis, targeted therapy as well as strategies for modulating their expression in a therapeutic context. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Processing > Processing of Small RNAs RNA in Disease and Development > RNA in Disease Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs.

Glypican 6 is a putative biomarker for metastatic progression of cutaneous melanoma

Due to the poor prognosis of advanced metastatic melanoma, it is crucial to find early biomarkers that help identify which melanomas will metastasize. By comparing the gene expression data from primary and cutaneous melanoma samples from The Cancer Genome Atlas (TCGA), we identified GPC6 among a set of genes whose expression levels can distinguish between primary melanoma and regional cutaneous/subcutaneous metastases. Glypicans are thought to play a role in tumor growth by regulating the signaling pathways of Wnt, Hedgehogs, fibroblast growth factors (FGFs), and bone morphogenetic proteins (BMPs). We showed that GPC6 expression was up-regulated in a melanoma cell line compared to normal melanocytes and in metastatic melanoma compared to primary melanoma. Furthermore, GPC6 expression was positively correlated with genes largely involved in cell adhesion and migration in both melanoma samples and in RNA-seq samples from other TCGA tumors. Our results suggest that GPC6 may play a role in tumor metastatic progression. In TCGA melanoma samples, we also showed that GPC6 expression was negatively correlated with miR-509-3p, which has previously been shown to function as a tumor suppressor in various cancer cell lines. We overexpressed miR-509-3p in A375 melanoma cells and showed that GPC6 expression was significantly suppressed. This result suggested that GPC6 was a putative target of miR-509-3p in melanoma. Together, our findings identified GPC6 as an early biomarker for melanoma metastatic progression, one that can be regulated by miR-509-3p.

Somatic Mutations in miRNA Genes in Lung Cancer-Potential Functional Consequences of Non-Coding Sequence Variants

A growing body of evidence indicates that miRNAs may either drive or suppress oncogenesis. However, little is known about somatic mutations in miRNA genes. To determine the frequency and potential consequences of miRNA gene mutations, we analyzed whole exome sequencing datasets of 569 lung adenocarcinoma (LUAD) and 597 lung squamous cell carcinoma (LUSC) samples generated in The Cancer Genome Atlas (TCGA) project. Altogether, we identified 1091 somatic sequence variants affecting 522 different miRNA genes and showed that half of all cancers had at least one such somatic variant/mutation. These sequence variants occurred in most crucial parts of miRNA precursors, including mature miRNA and seed sequences. Due to our findings, we hypothesize that seed mutations may affect miRNA:target interactions, drastically changing the pool of predicted targets. Mutations may also affect miRNA biogenesis by changing the structure of miRNA precursors, DROSHA and DICER cleavage sites, and regulatory sequence/structure motifs. We identified 10 significantly overmutated hotspot miRNA genes, including the miR-379 gene in LUAD enriched in mutations in the mature miRNA and regulatory sequences. The occurrence of mutations in the hotspot miRNA genes was also shown experimentally. We present a comprehensive analysis of somatic variants in miRNA genes and show that some of these genes are mutational hotspots, suggesting their potential role in cancer.

Predicting cancer cell invasion by single-cell physical phenotyping

The physical properties of cells are promising biomarkers for cancer diagnosis and prognosis. Here we determine the physical phenotypes that best distinguish human cancer cell lines, and their relationship to cell invasion. We use the high throughput, single-cell microfluidic method, quantitative deformability cytometry (q-DC), to measure six physical phenotypes including elastic modulus, cell fluidity, transit time, entry time, cell size, and maximum strain at rates of 102 cells per second. By training a k-nearest neighbor machine learning algorithm, we demonstrate that multiparameter analysis of physical phenotypes enhances the accuracy of classifying cancer cell lines compared to single parameters alone. We also discover a set of four physical phenotypes that predict invasion; using these four parameters, we generate the physical phenotype model of invasion by training a multiple linear regression model with experimental data from a set of human ovarian cancer cells that overexpress a panel of tumor suppressor microRNAs. We validate the model by predicting invasion based on measured physical phenotypes of breast and ovarian human cancer cell lines that are subject to genetic or pharmacologic perturbations. Taken together, our results highlight how physical phenotypes of single cells provide a biomarker to predict the invasion of cancer cells.

3D bioprinting for high-throughput screening: Drug screening, disease modeling, and precision medicine applications

High-throughput technologies have become essential in many fields of pharmaceutical and biological development and production. Such technologies were initially developed with compatibility with liquid handling-based cell culture techniques to produce large-scale 2D cell culture experiments for the compound analysis of candidate drug compounds. Over the past two decades, tools for creating 3D cell cultures, organoids, and other 3D in vitro models, such as cell supportive biomaterials and 3D bioprinting, have rapidly advanced. Concurrently, a significant body of evidence has accumulated which speaks to the many benefits that 3D model systems have over traditional 2D cell cultures. Specifically, 3D cellular models better mimic aspects such as diffusion kinetics, cell-cell interactions, cell-matrix interactions, inclusion of stroma, and other features native to in vivo tissue and as such have become an integral part of academic research. However, most high throughput assays were not developed to specifically support 3D systems. Here, we describe the need for improved compatibility and relevant advances toward deployment and adoption of high throughput 3D models to improve disease modeling, drug efficacy testing, and precision medicine applications.

A six-microRNA signature to predict outcomes of patients with gastric cancer

Gastric cancer (GC) is a common gastrointestinal tumor with poor prognosis. However, conventional prognostic factors cannot accurately predict the outcomes of GC patients. Therefore, there remains a need to identify novel predictive markers to improve prognosis. In this study, we obtained microRNA expression profiles of 385 GC patients from The Cancer Genome Atlas. We performed Cox regression analysis to identify overall survival‐related microRNA and then constructed a microRNA signature‐based prognostic model. The accuracy of the model was evaluated and validated through Kaplan–Meier survival analysis and time‐dependent receiver operating characteristic (ROC) curve analysis. The independent prognostic value of the model was assessed by multivariate Cox regression analysis. Enrichment analysis was performed to explore potential functions of the prognostic microRNA. Finally, a prognostic model based on a six‐microRNA (miRNA‐100, miRNA‐374a, miRNA‐509‐3, miRNA‐668, miRNA‐549, and miRNA‐653) signature was developed. Further analysis in the training, test, and complete The Cancer Genome Atlas set showed the model can distinguish between high‐risk and low‐risk patients and predict 3‐year and 5‐year survival. The six‐microRNA signature was also an independent prognostic marker, and enrichment analysis suggested that the microRNA may be involved in cell cycle and mitosis. These results demonstrated that the model based on the six‐microRNA signature can be used to accurately predict the prognosis of GC patients.

Upregulation of miR-614 promotes proliferation and inhibits apoptosis in ovarian cancer by suppressing PPP2R2A expression

It has previously been demonstrated that microRNAs (miRNAs) have essential roles and participate in various biological processes by regulating their specific target genes. However, the precise role of miRNAs in ovarian cancer (OC) has not yet been elucidated. The present study demonstrated that miR‑614 expression levels were significantly upregulated in OC tissues and cell lines, whereas decreased miR‑614 demonstrated opposite effects. Furthermore, gain‑of‑function and loss‑of‑function experiments indicated that miR‑614 overexpression promoted cell proliferation and suppressed cell apoptosis. Protein phosphatase 2 regulatory subunit B α, (PPP2R2A) was identified as a direct target of miR‑614 using western blotting and luciferase reporter assays. Notably, silencing of PPP2R2A counter‑acted the effect of miR‑614 inhibitor in OC cell proliferation and cell apoptosis. Overall, the data suggested that miR‑614 promoted cell proliferation and inhibited cell apoptosis of OC cells by targeting PPP2R2A, and may therefore act as a potential target for OC therapy in the future.

Potential microRNA-related Targets for Therapeutic Intervention with Ovarian Cancer Metastasis

Treatment of disseminated epithelial ovarian cancer (EOC) is an unmet medical need. Therefore, the identification along with preclinical and clinical validation of new targets is an issue of high importance. In this review we focus on microRNAs that mediate metastasis of EOC. We summarize up-regulated metastasis-promoting and down-regulated metastasis-suppressing microRNAs. We focus on preclinical in vitro and in vivo functions as well as their metastasis-related clinical correlations. Finally, we outline modalities for therapeutic intervention and critical issues of microRNA-based therapeutics in the context of metastatic EOC.

miR-509-3p promotes cisplatin-induced apoptosis in ovarian cancer cells through the regulation of anti-apoptotic genes

AIM

Previous observations have implicated miR-509-3p's ability in regulating cisplatin-triggered apoptosis in ovarian cancer. However, the underlying mechanisms were not fully understood.

MATERIALS & METHODS

The roles of miR-509-3p in cellular apoptosis were assessed through MTT and DAPI assays. The confirmation of the regulation of BCL2 family members by miR-509-3p was investigated by luciferase reporter assay, western blot, quantitative real-time PCR and rescue experiments.

RESULTS

MiR-509-3p can decrease the IC₅₀ values of cisplatin and promote apoptosis in ovarian cancer cells. Furthermore, on a panel of anti-apoptotic proteins, we identified that miR-509-3p could regulate BCL2, BCL2L2 and MCL1 via their 3'UTRs.

CONCLUSION

Our study demonstrates that miR-509-3p could sensitize ovarian cancer cells to cisplatin treatment by targeting multiple anti-apoptosis genes including BCL2.

MicroRNA‑509 acts as a tumor suppressor in tongue squamous cell carcinoma by targeting epidermal growth factor receptor

Tongue squamous cell carcinoma (TSCC) is the most frequent type of oral carcinoma, and is characterized by high metastatic and growth capabilities. Previous studies have demonstrated that aberrantly expressed cancer‑associated microRNAs (miRs) may be associated with tumorigenesis and tumor development in various types of cancer, including TSCC. miR‑509 has been identified as a critical regulator in tumorigenesis and tumor development, via its tumor‑suppressing actions in several types of human cancer. In the present study, miR‑509 expression in TSCC tissues and cell lines was determined by reverse transcription‑quantitative polymerase chain reaction. The effects of miR‑509 on TSCC cell proliferation and invasion were evaluated via MTT and invasion assays, respectively. In addition, the direct target of miR‑509 in TSCC was investigated. The present study demonstrated that miR‑509 expression was downregulated in TSCC tissue samples and cell lines, whereas its ectopic expression suppressed TSCC cell proliferation and invasion in vitro. In addition, epidermal growth factor receptor (EGFR) was identified as a direct target gene of miR‑509 in TSCC cells. EGFR downregulation was demonstrated to suppress the proliferation and invasion of TSCC cells, similar to miR‑509 overexpression. Furthermore, EGFR was significantly upregulated in TSCC tissues, and the levels of miR‑509 were revealed to be negatively correlated with EGFR expression in TSCC tissues. Following transfection with miR‑509 mimics, signaling pathways downstream of EGFR appeared to be suppressed, as phosphorylated (p)‑extracellular signal‑regulated kinase and p‑Akt were downregulated in TSCC cells. In conclusion, the results of the present study suggested that miR‑509 may inhibit the proliferation and invasion of TSCC cells via directly targeting EGFR, thus suggesting that the miR‑509/EGFR axis may have potential as a novel therapeutic target for the development of a treatment for patients with TSCC.

MicroRNA‑1288 promotes cell proliferation of human glioblastoma cells by repressing ubiquitin carboxyl‑terminal hydrolase CYLD expression

Previous studies have demonstrated that microRNAs (miRs) are important regulators involved in various cancers, including human glioblastoma (GBM). However, the underlying mechanism of miR-1288 remains poorly understood, and its role in GBM has not been reported. The present study confirmed that miR-1288 expression was markedly upregulated in GBM. Ectopic expression of miR-1288 promoted the proliferation, colony formation and anchorage-independent growth of GBM cells. Bioinformatics analysis coupled with western blotting and luciferase report assays also indicated that miR-1288 promoted cell proliferation of GBM by targeting ubiquitin carboxyl-terminal hydrolase (CYLD). Knockdown of CYLD expression reversed the cell proliferation promotion by miR-1288-in in GBM. These results suggest that the miR-1288/CYLD axis may represent a potential therapeutic target for the treatment of GBM.

CG200745, an HDAC inhibitor, induces anti-tumour effects in cholangiocarcinoma cell lines via miRNAs targeting the Hippo pathway

Cholangiocarcinoma is a devastating malignancy with fatal complications that exhibits low response and resistance to chemotherapy. Here, we evaluated the anticancer effects of CG200745, a novel histone deacetylase inhibitor, either alone or in combination with standard chemotherapy drugs in cholangiocarcinoma cells. CG200745 dose-dependently reduced the viability of cholangiocarcinoma cells in vitro and decreased tumour volume and weight in a xenograft model. Administering CG200745 along with other chemotherapeutic agents including gemcitabine, 5-fluorouracil (5-FU), cisplatin, oxaliplatin, or gemcitabine plus cisplatin further decreased cholangiocarcinoma cell viability, with a combination index < 1 that indicated synergistic action. CG200745 also enhanced the sensitivity of gemcitabine-resistant cells to gemcitabine and 5-FU, thereby decreasing cell viability and inducing apoptosis. This was accompanied by downregulation of YAP, TEAD4, TGF-β2, SMAD3, NOTCH3, HES5, Axl, and Gas6 and upregulation of the miRNAs miR-22-3p, miR-22-5p, miR-194-5p, miR-194-3p, miR-194-5p, miR-210-3p, and miR-509-3p. The Ingenuity Pathway Analysis revealed that CG200745 mainly targets the Hippo signalling pathway by inducing miR-509-3p expression. Thus, CG200745 inhibits cholangiocarcinoma growth in vitro and in vivo, and acts synergistically when administered in combination with standard chemotherapeutic agents, enabling dose reduction. CG200745 is therefore expected to improve the outcome of cholangiocarcinoma patients who exhibit resistance to conventional therapies.

Molecular Mechanisms of Ovarian Carcinoma Metastasis: Key Genes and Regulatory MicroRNAs

Metastasis of primary tumors progresses stepwise - from change in biochemistry, morphology, and migratory patterns of tumor cells to the emergence of receptors on their surface that facilitate directional migration to target organs followed by the formation of a specific microenvironment in a target organ that helps attachment and survival of metastatic cells. A set of specific genes and signaling pathways mediate this process under control of microRNA. The molecular mechanisms underlying biological processes associated with tumor metastasis are reviewed in this publication using ovarian cancer, which exhibits high metastatic potential, as an example. Information and data on the genes and regulatory microRNAs involved in the formation of cancer stem cells, epithelial-mesenchymal transition, reducing focal adhesion, degradation of extracellular matrix, increasing migration activity of cancer cells, formation of spheroids, apoptosis, autophagy, angiogenesis, formation of metastases, and development of ascites are presented. Clusters of microRNAs (miR-145, miR-31, miR-506, miR-101) most essential for metastasis of ovarian cancer including the families of microRNAs (miR-200, miR-214, miR-25) with dual role, which is different in different histological types of ovarian cancer, are discussed in detail in a section of the review.

Integrated analysis identifies microRNA-195 as a suppressor of Hippo-YAP pathway in colorectal cancer

Background

With persistent inconsistencies in colorectal cancer (CRC) miRNAs expression data, it is crucial to shift toward inclusion of a “pre-laboratory” integrated analysis to expedite effective precision medicine and translational research. Aberrant expression of hsa-miRNA-195 (miR-195) which is distinguished as a clinically noteworthy miRNA has previously been observed in multiple cancers, yet its role in CRC remains unclear.

Methods

In this study, we performed an integrated analysis of seven CRC miRNAs expression datasets. The expression of miR-195 was validated in The Cancer Genome Atlas (TCGA) datasets, and an independent validation sample cohort. Colon cancer cells were transfected with miR-195 mimic and inhibitor, after which cell proliferation, colony formation, migration, invasion, and dual luciferase reporter were assayed. Xenograft mouse models were used to determine the role of miR-195 in CRC tumorigenicity in vivo.

Results

Four downregulated miRNAs (hsa-let-7a, hsa-miR-125b, hsa-miR-145, and hsa-miR-195) were demonstrated to be potentially useful diagnostic markers in the clinical setting. CRC patients with a decreased level of miR-195-5p in tumor tissues had significantly shortened survival as revealed by the TCGA colon adenocarcinoma (COAD) dataset and our CRC cohort. Overexpression of miR-195-5p in DLD1 and HCT116 cells repressed cell growth, colony formation, invasion, and migration. Inhibition of miR-195-5p function contributed to aberrant cell proliferation, migration, invasion, and epithelial mesenchymal transition (EMT). We identified miR-195-5p binding sites within the 3’-untranslated region (3′-UTR) of the human yes-associated protein (YAP) mRNA. YAP1 expression was downregulated after miR-195-5p treatment by qRT-PCR analysis and western blot.

Conclusions

Four downregulated miRNAs were shown to be prime candidates for a panel of biomarkers with sufficient diagnostic accuracy for CRC in a clinical setting. Our integrated microRNA profiling approach identified miR-195-5p independently associated with prognosis in CRC. Our results demonstrated that miR-195-5p was a potent suppressor of YAP1, and miR-195-5p-mediated downregulation of YAP1 significantly reduced tumor development in a mouse CRC xenograft model. In the clinic, miR-195-5p can serve as a prognostic marker to predict the outcome of the CRC patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-017-0445-8) contains supplementary material, which is available to authorized users.

SPARC overexpression alters microRNA expression profiles involved in tumor progression

Medulloblastoma is the most common malignant brain tumor in children. SPARC (secreted protein acidic and rich in cysteine), a multicellular non-structural glycoprotein is known to be involved in multiple processes in various cancers. Previously, we reported that SPARC expression significantly impairs medulloblastoma tumor growth in vitro and in vivo and also alters chemo sensitivity. MicroRNAs are a class of post-transcriptional gene regulators with critical functions in tumor progression. In addition, microRNA (miRNA) expression changes are also involved in chemo-resistance. Herein, we assessed microRNA (miRNA) profiling to identify the functional network and biological pathways altered in SPARC-overexpressed medulloblastoma cells. A total of 27 differentially expressed miRNAs were identified between the control and SPARC-overexpressed samples. Potential messenger RNA (mRNA) targets of the differentially expressed miRNA were identified using Ingenuity Pathway Analysis (IPA). Network-based functional analyses were performed on the available human protein interaction and miRNA-gene association data to highlight versatile miRNAs among the significantly deregulated miRNAs using the IPA, and the biological pathway analysis using the PANTHER web-based tool. We have identified six miRNAs (miR-125b1*, miR-146a-5p, miR-181a-5p, miR-204-5p, miR-219-5p and miR-509-3p) that are associated with SPARC sensitivity by comparison of miRNA expression patterns from the SPARC treated cells with the control cells. Furthermore, pathway enrichment analysis outline that these six microRNAs mainly belong to biological processes related to cancer related signaling pathways. Collectively, these studies have the potential to indicate novel biomarkers for treatment response and can also be applied to develop novel therapeutic treatment for medulloblastoma.

Associations of five polymorphisms in the CD44 gene with cancer susceptibility in Asians

CD44 polymorphisms have been previously associated with cancer risk. However, the results between independent studies were inconsistent. Here, a meta-analysis was performed to systematically evaluate associations between CD44 polymorphisms and cancer susceptibility. A comprehensive literature search conducted in PubMed, Embase, and Web of Science databases through August 10, 2016 yielded 11 eligible publications consisting of 5,788 cancer patients and 5,852 controls. Overall, odds ratios (OR) calculated with 95% confidence intervals (CI) identified a significant association between CD44 polymorphism rs13347 and cancer susceptibility under all genetic models. Additionally, the minor allele of polymorphism rs11821102 was associated with a decreased susceptibility to cancer in allele contrast, dominant, and heterozygous models, while no significant association was identified for polymorphisms rs10836347, rs713330, or rs1425802. Subgroup analysis by ethnicity revealed rs13347 was significantly associated with cancer susceptibility for Chinese but not for Indians. Linkage disequilibrium (LD) between different polymorphisms varied across diverse ethnic populations. In conclusion, the results indicate that CD44 polymorphism rs13347 acts as a risk factor for cancer, especially in Chinese, while the minor allele of polymorphism rs11821102 may be associated with a decreased susceptibility to cancer. Nevertheless, further studies on a larger population covering different ethnicities are warranted.

Cancer cells become less deformable and more invasive with activation of β-adrenergic signaling

Invasion by cancer cells is a crucial step in metastasis. An oversimplified view in the literature is that cancer cells become more deformable as they become more invasive. β-adrenergic receptor (βAR) signaling drives invasion and metastasis, but the effects on cell deformability are not known. Here, we show that activation of β-adrenergic signaling by βAR agonists reduces the deformability of highly metastatic human breast cancer cells, and that these stiffer cells are more invasive in vitro We find that βAR activation also reduces the deformability of ovarian, prostate, melanoma and leukemia cells. Mechanistically, we show that βAR-mediated cell stiffening depends on the actin cytoskeleton and myosin II activity. These changes in cell deformability can be prevented by pharmacological β-blockade or genetic knockout of the β₂-adrenergic receptor. Our results identify a β₂-adrenergic-Ca²⁺-actin axis as a new regulator of cell deformability, and suggest that the relationship between cell mechanical properties and invasion might be dependent on context.

Tumour-suppressor microRNAs regulate ovarian cancer cell physical properties and invasive behaviour

The activities of pathways that regulate malignant transformation can be influenced by microRNAs (miRs). Recently, we showed that increased expression of five tumour-suppressor miRs, miR-508-3p, miR-508-5p, miR-509-3p, miR-509-5p and miR-130b-3p, correlate with improved clinical outcomes in human ovarian cancer patients, and that miR-509-3p attenuates invasion of ovarian cancer cell lines. Here, we investigate the mechanism underlying this reduced invasive potential by assessing the impact of these five miRs on the physical properties of cells. Human ovarian cancer cells (HEYA8, OVCAR8) that are transfected with miR mimics representing these five miRs exhibit decreased invasion through collagen matrices, increased cell size and reduced deformability as measured by microfiltration and microfluidic assays. To understand the molecular basis of altered invasion and deformability induced by these miRs, we use predicted and validated mRNA targets that encode structural and signalling proteins that regulate cell mechanical properties. Combined with analysis of gene transcripts by real-time PCR and image analysis of F-actin in single cells, our results suggest that these tumour-suppressor miRs may alter cell physical properties by regulating the actin cytoskeleton. Our findings provide biophysical insights into how tumour-suppressor miRs can regulate the invasive behaviour of ovarian cancer cells, and identify potential therapeutic targets that may be implicated in ovarian cancer progression.