Identification of long intergenic non-coding RNAs (lincRNAs) deregulated in gastrointestinal stromal tumors (GISTs)

Investigating SNHG3 and BCYRN1 lncRnas expression in the peripheral blood cells of multiple sclerosis patients

BACKGROUND

MS (Multiple sclerosis) is a progressive neurologic disorder often appearing in the third decade of life. MS is the most frequent demyelinating disease of the central nervous system. The development of MS is influenced by environmental, genetic, and epigenetic factors. The bulk of the human transcriptome comprises lncRNAs, which play crucial regulatory roles. We aimed to assess the SNHG3 and BCYRN1 lncRNA expression in blood samples from MS patients and how these lncRNAs and disease activity are related.

METHODS

A total of 100 MS patients, including 8 primary progressive (PP), 82 relapsing-remitting (RR), and 10 secondary progressive (SP) MS, as well as 100 healthy controls, had their blood samples taken. Gene expression was assessed using quantitative real-time PCR. Recognizing the receiver operating characteristic (ROC) curve analysis, the diagnostic potential of lncRNA levels was evaluated.

RESULTS

Expressions of SNHG3 and BCYRN1 were found to have significantly increased (p < 0.0001). SNHG3 expression level showed significant differences compared to age groups and MS subtypes (p value = 0.001 and p value = 0.02).Furthermore, patients with a family history showed elevated BCYRN1 expression with a p value of 0.01. Considering the age factor, BCYRN1 exhibits altered expression levels in patient groups compared to healthy controls (p value 0.04). Additionally, the novel biomarkers SNHG3 and BCYRN1 can be used to diagnose MS (AUC = 0.97 and AUC = 0.88, respectively).

DISCUSSION

Increased levels of SNHG3 and BCYRN1 in the serum may serve as potential molecular biomarkers for the MS diagnosis.

KIT mutations and expression: current knowledge and new insights for overcoming IM resistance in GIST

Gastrointestinal stromal tumor (GIST) is the most common sarcoma located in gastrointestinal tract and derived from the interstitial cell of Cajal (ICC) lineage. Both ICC and GIST cells highly rely on KIT signal pathway. Clinically, about 80-90% of treatment-naive GIST patients harbor primary KIT mutations, and special KIT-targeted TKI, imatinib (IM) showing dramatic efficacy but resistance invariably occur, 90% of them was due to the second resistance mutations emerging within the KIT gene. Although there are multiple variants of KIT mutant which did not show complete uniform biologic characteristics, most of them have high KIT expression level. Notably, the high expression level of KIT gene is not correlated to its gene amplification. Recently, accumulating evidences strongly indicated that the gene coding, epigenetic regulation, and pre- or post- protein translation of KIT mutants in GIST were quite different from that of wild type (WT) KIT. In this review, we elucidate the biologic mechanism of KIT variants and update the underlying mechanism of the expression of KIT gene, which are exclusively regulated in GIST, providing a promising yet evidence-based therapeutic landscape and possible target for the conquer of IM resistance. Video Abstract.

Up-regulation of BOK-AS1, FAM215A and FEZF1-AS1 lncRNAs and their potency as moderate diagnostic biomarkers in gastric cancer

BACKGROUND

Gastric cancer is the fifth most frequent cancer worldwide and the fourth leading cause of death from cancer, a complex multifactorial neoplasm. LncRNAs are regulatory RNA molecules larger than 200 nucleotides, which can have profound effects on the oncogenic process of various types of cancer. Therefore, these molecules can be used as diagnostic and therapeutic biomarkers. This study aimed to determine the differences in BOK-AS1, FAM215A, and FEZF1-AS1 gene expression between tumor tissue and adjacent healthy non-tumor tissue of gastric cancer (GC) patients.

METHODS

In this study one hundred pairs of cancerous and non-cancerous marginal tissues were gathered. Next, RNA extraction and cDNA synthesis were achieved for all of the samples. Then, the qRT-PCR was performed to measure the expression of BOK-AS1, FAM215A and FEZF1-AS1 genes.

RESULTS

All BOK-AS1, FAM215A and FEZF1-AS1 genes showed significantly increased expression in tumor tissues compared with non-tumor tissues. The outcome of the ROC analysis demonstrated that BOK-AS1, FAM215A, and FEZF1-AS1 may act as mean biomarkers with AUC of 0.7368, 0.7163 and 0.7115, specificity of 64%, 61% and 59%, and sensitivity of 74%, 70%, and 74% respectively.

CONCLUSION

Based on the increased expression of the BOK-AS1, FAM215A and FEZF1-AS1 genes in GC patients, this study suggests that these genes may function as oncogenic factors. Furthermore, the mentioned genes can be considered as intermediate biomarkers for diagnosis and treatment of gastric cancer. In addition, no association between these genes and clinicopathological features was observed.

Validation of a Salivary miRNA Signature of Endometriosis - Interim Data

BACKGROUND: The discovery of a saliva-based micro–ribonucleic acid (miRNA) signature for endometriosis in 2022 opened up new perspectives for early and noninvasive diagnosis of the disease. The 109-miRNA saliva signature is the product of miRNA biomarkers and artificial intelligence (AI) modeling. We designed a multicenter study to provide external validation of its diagnostic accuracy. We present here an interim analysis. METHODS: The first 200 patients included in the multicenter prospective ENDOmiRNA Saliva Test study (NCT05244668) were included for interim analysis. The study population comprised women from 18 to 43 years of age with a formal diagnosis of endometriosis or with suspected endometriosis. Epidemiologic, clinical, and saliva sequencing data were collected between November 2021 and March 2022. Genomewide miRNA expression profiling by small RNA sequencing using next-generation sequencing (NGS) was performed, and a random forest algorithm was used to assess the diagnostic accuracy. RESULTS: In this interim analysis of the external validation cohort, with a population prevalence of 79.5%, the 109-miRNA saliva diagnostic signature for endometriosis had a sensitivity of 96.2% (95% confidence interval [CI], 93.7 to 97.3%), specificity of 95.1% (95% CI, 85.2 to 99.1%), positive predictive value of 95.1% (95% CI, 85.2 to 99.1%), negative predictive value of 86.7% (95% CI, 77.6 to 90.3%), positive likelihood ratio of 19.7 (95% CI, 6.3 to 108.8), negative likelihood ratio of 0.04 (95% CI, 0.03 to 0.07), and area under the receiver operating characteristic curve of 0.96 (95% CI, 0.92 to 0.98). CONCLUSIONS: The use of NGS and AI in the sequencing and analysis of miRNA provided a saliva-based miRNA signature for endometriosis. Our interim analysis of a prospective multicenter external validation study provides support for its ongoing investigation as a diagnostic tool. (Funded by Ziwig and the Conseil Régional d’Ile de France [Grant EX024087]; ClinicalTrials.gov number, NCT05244668.)

Development and characterization of an ETV1 rabbit monoclonal antibody for the immunohistochemical detection of ETV1 expression in cancer tissue specimens

BACKGROUND

Aberrant ETV1 overexpression arising from gene rearrangements or mutations occur frequently in prostate cancer, round cell sarcomas, gastrointestinal stromal tumors, gliomas, and other malignancies. The absence of specific monoclonal antibodies (mAb) has limited its detection and our understanding of its oncogenic function.

METHODS

An ETV1 specific rabbit mAb (29E4) was raised using an immunogenic peptide. Key residues essential for its binding were probed by ELISA and its binding kinetics were measured by surface plasmon resonance imaging (SPRi). Its selective binding to ETV1 was assessed by immunoblots and immunofluorescence assays (IFA), and by both single and double-immuno-histochemistry (IHC) assays on prostate cancer tissue specimens.

RESULTS

Immunoblot results showed that the mAb is highly specific and lacked cross-reactivity with other ETS factors. A minimal epitope with two phenylalanine residues at its core was found to be required for effective mAb binding. SPRi measurements revealed an equilibrium dissociation constant in the picomolar range, confirming its high affinity. ETV1 (+) tumors were detected in prostate cancer tissue microarray cases evaluated. IHC staining of whole-mounted sections revealed glands with a mosaic staining pattern of cells that are partly ETV1 (+) and interspersed with ETV1 (-) cells. Duplex IHC, using ETV1 and ERG mAbs, detected collision tumors containing glands with distinct ETV1 (+) and ERG (+) cells.

CONCLUSIONS

The selective detection of ETV1 by the 29E4 mAb in immunoblots, IFA, and IHC assays using human prostate tissue specimens reveals a potential utility for the diagnosis, the prognosis of prostate adenocarcinoma and other cancers, and the stratification of patients for treatment by ETV1 inhibitors.

HCG11 inhibits salivary adenoid cystic carcinoma by upregulating EphA2 via binding to miR-1297

OBJECTIVE

Ephrin receptor A2 (EphA2) was reported to be related to the tumorigenesis of salivary adenoid cystic carcinoma (SACC), which is a rare malignancy accounting for less than 1% of all oral and maxillofacial tumors. This research aimed to assess the molecular mechanisms of EphA2 in SACC.

STUDY DESIGN

The expression of long non-coding RNA human leukocyte antigen complex group 11 (HCG11), microRNA-1297 (miR-1297), and EphA2 in SACC cell lines compared with normal human salivary gland (HSG) cell line was measured by reverse transcription-quantitative polymerase chain reaction. EphA2 protein level was detected by western blot. 5-ethynyl-2'-deoxyuridine (EdU), colony formation, Transwell, and wounding healing experiments were applied to evaluate SACC cell proliferation, migration, and invasion. The relationship among HCG11, miR-1297, and EphA2 was confirmed by luciferase reporter, RNA pulldown, and RNA immunoprecipitation experiments.

RESULTS

HCG11 and EphA2 were downregulated while miR-1297 was upregulated in SACC cells. EphA2 overexpression suppressed SACC cell proliferation, migration, and invasion. HCG11 bound to miR-1297 to reduce the inhibition of miR-1297 on EphA2 expression. EphA2 knockdown reversed the suppression of HCG11 overexpression on SACC cell phenotypes.

CONCLUSION

This study identified the HCG11/miR-1297/EphA2 regulatory axis in SACC, which might provide novel therapeutic targets for SACC.

Endometriosis-associated infertility diagnosis based on saliva microRNA signatures

RESEARCH QUESTION

Can a saliva-based miRNA signature for endometriosis-associated infertility be designed and validated by analysing the human miRNome?

DESIGN

The prospective ENDOmiARN study (NCT04728152) included 200 saliva samples obtained between January 2021 and June 2021 from women with pelvic pain suggestive of endometriosis. All patients underwent either laparoscopy, magnetic resonance imaging, or both. Patients diagnosed with endometriosis were allocated to one of two groups according to their fertility status. Data analysis consisted of identifying a set of miRNA biomarkers using next-generation sequencing, and development of a saliva-based miRNA signature of infertility among patients with endometriosis based on a random forest model.

RESULTS

Among the 153 patients diagnosed with endometriosis, 24% (n = 36) were infertile and 76% (n = 117) were fertile. Small RNA-sequencing of the 153 saliva samples yielded approximately 3712 M raw sequencing reads (from ∼13.7 M to ∼39.3 M reads/sample). Of the 2561 known miRNAs, the feature selection method generated a signature of 34 miRNAs linked to endometriosis-associated infertility. After validation, the most accurate signature model had a sensitivity, specificity and area under the curve of 100%.

CONCLUSION

A saliva-based miRNA signature for endometriosis-associated infertility is reported. Although the results still require external validation before using the signature in routine practice, this non-invasive tool is likely to have a major effect on care provided to women with endometriosis.

A Bioinformatics Approach to MicroRNA-Sequencing Analysis Based on Human Saliva Samples of Patients with Endometriosis

Endometriosis, defined by the presence of endometrium-like tissue outside the uterus, affects 2-10% of the female population, i.e., around 190 million women, worldwide. The aim of the prospective ENDO-miRNA study was to develop a bioinformatics approach for microRNA-sequencing analysis of 200 saliva samples for miRNAome expression and to test its diagnostic accuracy for endometriosis. Among the 200 patients, 76.5% (n = 153) had confirmed endometriosis and 23.5% (n = 47) had no endometriosis (controls). Small RNA-seq of 200 saliva samples yielded ~4642 M raw sequencing reads (from ~13.7 M to ~39.3 M reads/sample). The number of expressed miRNAs ranged from 1250 (outlier) to 2561 per sample. Some 2561 miRNAs were found to be differentially expressed in the saliva samples of patients with endometriosis compared with the control patients. Among these, 1.17% (n = 30) were up- or downregulated. Among these, the F1-score, sensitivity, specificity, and AUC ranged from 11-86.8%, 5.8-97.4%, 10.6-100%, and 39.3-69.2%, respectively. Here, we report a bioinformatic approach to saliva miRNA sequencing and analysis. We underline the advantages of using saliva over blood in terms of ease of collection, reproducibility, stability, safety, non-invasiveness. This report describes the whole saliva transcriptome to make miRNA quantification a validated, standardized, and reliable technique for routine use. The methodology could be applied to build a saliva signature of endometriosis.

Endometriosis Associated-miRNome Analysis of Blood Samples: A Prospective Study

The aim of our study was to describe the bioinformatics approach to analyze miRNome with Next Generation Sequencing (NGS) of 200 plasma samples from patients with and without endometriosis. Patients were prospectively included in the ENDO-miRNA study that selected patients with pelvic pain suggestive of endometriosis. miRNA sequencing was performed using an Novaseq6000 sequencer (Illumina, San Diego, CA, USA). Small RNA-seq of 200 plasma samples yielded ~4228 M raw sequencing reads. A total of 2633 miRNAs were found differentially expressed. Among them, 8.6% (n = 229) were up- or downregulated. For these 229 miRNAs, the F1-score, sensitivity, specificity, and AUC ranged from 0-88.2%, 0-99.4%, 4.3-100%, and 41.5-68%, respectively. Utilizing the combined bioinformatic and NGS approach, a specific and broad panel of miRNAs was detected as being potentially suitable for building a blood signature of endometriosis.

MicroRNome analysis generates a blood-based signature for endometriosis

Endometriosis, characterized by endometrial-like tissue outside the uterus, is thought to affect 2-10% of women of reproductive age: representing about 190 million women worldwide. Numerous studies have evaluated the diagnostic value of blood biomarkers but with disappointing results. Thus, the gold standard for diagnosing endometriosis remains laparoscopy. We performed a prospective trial, the ENDO-miRNA study, using both Artificial Intelligence (AI) and Machine Learning (ML), to analyze the current human miRNome to differentiate between patients with and without endometriosis, and to develop a blood-based microRNA (miRNA) diagnostic signature for endometriosis. Here, we present the first blood-based diagnostic signature obtained from a combination of two robust and disruptive technologies merging the intrinsic quality of miRNAs to condense the endometriosis phenotype (and its heterogeneity) with the modeling power of AI. The most accurate signature provides a sensitivity, specificity, and Area Under the Curve (AUC) of 96.8%, 100%, and 98.4%, respectively, and is sufficiently robust and reproducible to replace the gold standard of diagnostic surgery. Such a diagnostic approach for this debilitating disorder could impact recommendations from national and international learned societies.

Salivary MicroRNA Signature for Diagnosis of Endometriosis

BACKGROUND

Endometriosis diagnosis constitutes a considerable economic burden for the healthcare system with diagnostic tools often inconclusive with insufficient accuracy. We sought to analyze the human miRNAome to define a saliva-based diagnostic miRNA signature for endometriosis.

METHODS

We performed a prospective ENDO-miRNA study involving 200 saliva samples obtained from 200 women with chronic pelvic pain suggestive of endometriosis collected between January and June 2021. The study consisted of two parts: (i) identification of a biomarker based on genome-wide miRNA expression profiling by small RNA sequencing using next-generation sequencing (NGS) and (ii) development of a saliva-based miRNA diagnostic signature according to expression and accuracy profiling using a Random Forest algorithm.

RESULTS

Among the 200 patients, 76.5% (n = 153) were diagnosed with endometriosis and 23.5% (n = 47) without (controls). Small RNA-seq of 200 saliva samples yielded ~4642 M raw sequencing reads (from ~13.7 M to ~39.3 M reads/sample). Quantification of the filtered reads and identification of known miRNAs yielded ~190 M sequences that were mapped to 2561 known miRNAs. Of the 2561 known miRNAs, the feature selection with Random Forest algorithm generated after internally cross validation a saliva signature of endometriosis composed of 109 miRNAs. The respective sensitivity, specificity, and AUC for the diagnostic miRNA signature were 96.7%, 100%, and 98.3%.

CONCLUSIONS

The ENDO-miRNA study is the first prospective study to report a saliva-based diagnostic miRNA signature for endometriosis. This could contribute to improving early diagnosis by means of a non-invasive tool easily available in any healthcare system.

Clues for Improving the Pathophysiology Knowledge for Endometriosis Using Plasma Micro-RNA Expression

The pathophysiology of endometriosis remains poorly understood. The aim of the present study was to investigate functions and pathways associated with the various miRNAs differentially expressed in patients with endometriosis. Plasma samples of the 200 patients from the prospective "ENDO-miRNA" study were analyzed and all known human miRNAs were sequenced. For each miRNA, sensitivity, specificity, and ROC AUC values were calculated for the diagnosis of endometriosis. miRNAs with an AUC ≥ 0.6 were selected for further analysis. A comprehensive review of recent articles from the PubMed, Clinical Trials.gov, Cochrane Library, and Web of Science databases was performed to identify functions and pathways associated with the selected miRNAs. In total, 2633 miRNAs were found in the patients with endometriosis. Among the 57 miRNAs with an AUC ≥ 0.6: 20 had never been reported before; one (miR-124-3p) had previously been observed in endometriosis; and the remaining 36 had been reported in benign and malignant disorders. miR-124-3p is involved in ectopic endometrial cell proliferation and invasion and plays a role in the following pathways: mTOR, STAT3, PI3K/Akt, NF-κB, ERK, PLGF-ROS, FGF2-FGFR, MAPK, GSK3B/β-catenin. Most of the remaining 36 miRNAs are involved in carcinogenesis through cell proliferation, apoptosis, and invasion. The three main pathways involved are Wnt/β-catenin, PI3K/Akt, and NF-KB. Our results provide evidence of the relation between the miRNA profiles of patients with endometriosis and various signaling pathways implicated in its pathophysiology.

PVT1 and ZFAS1 lncRNAs expressions and their biomarker value in gastric cancer tissue sampling among Iranian population

BACKGROUND

lncRNAs are modulatory factors with critical function in the tumorigenesis pathways, introducing them as promising therapeutic and diagnostic biomarkers for different cancers. This study is thus aimed to evaluate the differences in PVT1 and ZFAS1 gene expression in tumorous tissues as compared with adjacent healthy non-tumorous biopsies of gastric cancer cases.

METHODS

One hundred two pairs of tumorous and adjacent non-tumorous biopsies of GC cases were sampled. RNA isolation and cDNA production were carried out. The qRT-PCR was performed to evaluate the expression of PVT1 and ZFAS1 genes. Moreover, the associations between PVT1 or ZFAS1 and clinicopathological characteristics as well as the biomarker roles of the lncRNAs were assessed.

RESULTS

The PVT1 and ZFAS1 expressions showed a significant increase and decrease in GC samples as compared with non-cancerous tissues, respectively. PVT1 expression was significantly associated with and lymph-node involvement (p = 0.0007). Moreover, ZFAS1 expression demonstrated a significant association with lymph-node involvement (p = 0.0005), and tumor size >5 cm (p = 0.003). The findings of the ROC curve revealed that PVT1 and ZFAS1 may act as a possible biomarker with AUC of 0.71 and 0.79, specificity of 78.43% and 79.41%, and sensitivity of 55.88% and 64.71%.

CONCLUSIONS

Regarding upregulation of PVT1 and downregulation of ZFAS1 in human GC samples, these genes may respectively act as oncogenic and tumor-suppressive factors in GC cases. Furthermore, PVT1 and ZFAS1 can be considered as possible biomarkers for the detection and treatment of GC cases.

The Role of lncRNAs in Rare Tumors with a Focus on HOX Transcript Antisense RNA (HOTAIR)

Rare cancers are identified as those with an annual incidence of fewer than 6 per 100,000 persons and includes both epithelial and stromal tumors from different anatomical areas. The advancement of analytical methods has produced an accurate molecular characterization of most human cancers, suggesting a “molecular classification” that has allowed the establishment of increasingly personalized therapeutic strategies. However, the limited availability of rare cancer samples has resulted in very few therapeutic options for these tumors, often leading to poor prognosis. Long non coding RNAs (lncRNAs) are a class of non-coding RNAs mostly involved in tumor progression and drug response. In particular, the lncRNA HOX transcript antisense RNA (HOTAIR) represents an emergent diagnostic, prognostic and predictive biomarker in many human cancers. The aim of this review is to highlight the role of HOTAIR in rare cancers, proposing it as a new biomarker usable in the management of these tumors.

Integrated analysis of long non-coding RNAs and mRNAs associated with malignant transformation of gastrointestinal stromal tumors

Malignant transformation of gastrointestinal stromal tumors (GISTs) is correlated with poor prognosis; however, the underlying biological mechanism is not well understood. In the present study, low-risk (LR) GISTs, GISTs categorized as high-risk based on tumor size (HBS), and on mitotic rate (HBM) were collected for RNA sequencing. Candidate hub lncRNAs were selected by Oncomine analysis. Expression of a selected hub lncRNA, DNM3OS, and its correlation with patients’ prognosis were analyzed using FISH staining, followed with the determination of function and underlying mechanism. Our results revealed a series of key pathways and hub lncRNAs involved in the malignant transformation of GISTs. Oncomine analysis revealed a tight association between clinical signatures and DNM3OS and suggested that DNM3OS is a hub lncRNA that is involved in the Hippo signaling pathway. In addition, DNM3OS was upregulated in HBS, HBM, and HBS/M GIST and correlated with worse prognosis in patients with GISTs. In addition, DNM3OS promoted GIST cell proliferation and mitosis by regulating the expression of GLUT4 and CD36. Collectively, these results improve our understanding of the malignant transformation of GISTs and unveil a series of hub lncRNAs in GISTs.

FENDRR: A pivotal, cancer-related, long non-coding RNA

Long non-coding RNAs (lncRNAs) have more than 200 nucleotides and do not encode proteins. Based on numerous studies, lncRNAs have emerged as new and crucial regulators of biological function and have been implicated in the pathogenesis of a variety of diseases, especially cancers. Specific lncRNAs have been identified as novel molecular biomarkers for cancer diagnosis, prognosis, and treatment efficacy. Fetal-lethal non-coding developmental regulatory RNA (FENDRR, also known as FOXF1-AS1) is a novel lncRNA that is located at chr3q13.31 and has four exons and 3099 nucleotides, and its genomic site is located at chr3q13.31. FENDRR is abnormally expressed in a variety of cancers and is significantly associated with different clinical characteristics. In addition, FENDRR has shown potential as a biomarker for cancer diagnosis, prognosis, and treatment. In this review, we summarize the current understanding of FENDRR and its mechanistic role in cancer progression. We also discuss recent insights into the clinical significance of FENDRR for cancer diagnosis, prognosis, and treatment.

Overexpression of HOXA-AS2 LncRNA in Patients with Gastric Cancer and Its Association with Helicobacter pylori Infection

PURPOSE

LncRNAs are regulatory factors that play a prominent role in the carcinogenesis processes and cancer cell ability to invade and metastasize. Hence, lncRNAs are considered as the potential diagnostic and therapeutic biomarkers in diverse malignancies. The present study was designed to assess the difference of HOXA-AS2 gene expression levels in cancerous tissues as compared to marginal noncancerous tissues of gastric cancer patients.

METHODS

Fifty pairs of cancerous and marginal noncancerous tissue of gastric cancer patients were collected in the present study. Then, RNA extraction and cDNA synthesis were performed for all specimens. The qRT-PCR was carried out to examine the difference of HOXA-AS2 gene expression. Furthermore, the association between HOXA-AS2 expression and the clinicopathological features as well as the function of HOXA-AS2 biomarkers was evaluated.

RESULTS

The HOXA-AS2 expression was significantly elevated in cancerous tissues as compared to marginal noncancerous tissues in gastric cancer patients (p < 0.0001). Analysis of gene expression data revealed that there was a significant association between an increased HOXA-AS2 gene expression and clinicopathological features such as tumor size ˃ 5 cm (p = 0.009), lymph node metastasis (p = 0.028), and H. pylori infection (p = 0.011). The results of ROC analysis indicated that HOXA-AS2 with AUC, sensitivity, and specificity of 0.816, 92%, and 70%, respectively, can act as a potential biomarker (CI 95% = 0.7297-0.9023).

CONCLUSION

With regard to the overexpression of HOXA-AS2 in gastric cancer tissues, the mentioned gene may serve as an oncogenic lncRNA in gastric cancer patients. Moreover, HOXA-AS2 can act as a potential biomarker in molecular targeted therapies to recognize and treat gastric cancer patients.

Non-Coding RNAs, a Novel Paradigm for the Management of Gastrointestinal Stromal Tumors

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal malignancies found in the gastrointestinal tract. At a molecular level, most GISTs are characterized by gain-of-function mutations in V-Kit Hardy-Zuckerman 4 Feline Sarcoma Viral Oncogene Homolog (KIT) and Platelet Derived Growth Factor Receptor Alpha (PDGFRA), leading to constitutive activated signaling through these receptor tyrosine kinases, which drive GIST pathogenesis. In addition to surgery, treatment with the tyrosine kinase inhibitor imatinib forms the mainstay of GIST treatment, particularly in the advanced setting. Nevertheless, the majority of GISTs develop imatinib resistance. Biomarkers that indicate metastasis, drug resistance and disease progression early on could be of great clinical value. Likewise, novel treatment strategies that overcome resistance mechanisms are equally needed. Non-coding RNAs, particularly microRNAs, can be employed as diagnostic, prognostic or predictive biomarkers and have therapeutic potential. Here we review which non-coding RNAs are deregulated in GISTs, whether they can be linked to specific clinicopathological features and discuss how they can be used to improve the clinical management of GISTs.

Role of non-coding RNAs in pathogenesis of gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are considered the model solid malignancies of targeted therapy after the discovery of imatinib effectiveness against their tyrosine kinase inhibitors. Non-coding RNAs are molecules with no protein coding capacity that play crucial role to several biological steps of normal cell proliferation and differentiation. When the expression of these molecules found to be altered it seems that they affect the process of carcinogenesis in multiple ways, such as proliferation, apoptosis, differentiation, metastasis, and drug resistance. This review aims to provide an overview of the latest research papers and summarize the current evidence about the role of non-coding RNAs in pathogenesis of GISTs, including their potential clinical applications.

Metastasis Associated Lung Adenocarcinoma Transcript 1: An update on expression pattern and functions in carcinogenesis

The Metastasis Associated Lung Adenocarcinoma Transcript 1 (MALAT1) is among long non-coding RNAs (lncRNAs) which has disapproved the old term of "junk DNA" which was used for majority of human genome which are not transcribed to proteins. An extensive portion of literature points to the fundamental role of this lncRNA in tumorigenesis process of diverse cancers ranging from solid tumors to leukemia. Being firstly identified in lung cancer, it has prognostic and diagnostic values in several cancer types. Consistent with the proposed oncogenic roles for this lncRNA, most of studies have shown up-regulation of MALAT1 in malignant tissues compared with non-malignant/normal tissues of the same source. However, few studies have shown down-regulation of MALAT1 in breast cancer, endometrial cancer, colorectal cancer and glioma. In the current study, we have conducted a comprehensive literature search and provided an up-date on the role of MALAT1 in cancer biology. Our investigation underscores a potential role as a diagnostic/prognostic marker and a putative therapeutic target for MALAT1.

Gastrointestinal stromal tumor: epidemiology, diagnosis, and treatment

PURPOSE OF REVIEW

The purpose of this review is to review the past year's literature to provide comprehensive information to researchers, physicians, and the general public regarding the epidemiology, diagnosis, and treatment of gastrointestinal stromal tumors (GISTs). Common ground as well as divergent viewpoints will be highlighted and discussed.

RECENT FINDINGS

The diagnosis of GISTs may involve imaging tests such as computed tomorgraphy scan and MRI, endoscopy with or without endoscopic ultrasound, and biopsy. Only biopsy, however, can yield a positive diagnosis. As most GISTs express KIT protein, immunostaining for KIT and/or molecular genetic testing for mutations in KIT can diagnose 95% of GISTs. Regorafenib, a drug that inhibits various protein genes that lead to GIST development is a relatively new treatment modality.

SUMMARY

The current review should enable clinicians to best select the diagnostic and treatment approaches to GIST.

Differential chamber-specific expression and regulation of long non-coding RNAs during cardiac development

Cardiovascular development is governed by a complex interplay between inducting signals such as Bmps and Fgfs leading to activation of cardiac specific transcription factors such as Nkx2.5, Mef2c and Srf that orchestrate the initial steps of cardiogenesis. Over the last decade we have witnessed the discovery of novel layers of gene regulation, i.e. post-transcriptional regulation exerted by non-coding RNAs. The function role of small non coding RNAs has been widely demonstrated, e.g. miR-1 knockout display several cardiovascular abnormalities during embryogenesis. More recently long non-coding RNAs have been also reported to modulate gene expression and function in the developing heart, as exemplified by the embryonic lethal phenotypes of Fendrr and Braveheart knock out mice, respectively. In this study, we investigated the differential expression profile during cardiogenesis of previously reported lncRNAs in heart development. Our data revealed that Braveheart, Fendrr, Carmen display a preferential adult expression while Miat, Alien, H19 preferentially display chamber-specific expression at embryonic stages. We also demonstrated that these lncRNAs are differentially regulated by Nkx2.5, Srf and Mef2c, Pitx2 > Wnt > miRNA signaling pathway and angiotensin II and thyroid hormone administration. Importantly isoform-specific expression and distinct nuclear vs cytoplasmic localization of Braveheart, Carmen and Fendrr during chamber morphogenesis is observed, suggesting distinct functional roles of these lncRNAs in atrial and ventricular chambers. Furthermore, we demonstrate by in situ hybridization a dynamic epicardial, myocardial and endocardial expression of H19 during cardiac development. Overall our data support novel roles of these lncRNAs in different temporal and tissue-restricted fashion during cardiogenesis.

Association between genetic polymorphisms of long noncoding RNA H19 and cancer risk: a meta-analysis

Long noncoding RNA (lncRNA) H19, a well-known oncogenic lncRNA, is overexpressed in various cancers. Several studies have investigated the association between polymorphisms in lncRNA H19 and the risk of various cancer types; however, the findings were inconsistent. In this study, we performed a meta-analysis to identify the precise association between H19 polymorphisms and cancer risk. Appropriate studies were retrieved from searching Web of Science, PubMed, Scopus, and Google scholar databases, updated 25 November 2018. The pooled odds ratios (ORs with 95% confidence intervals (CIs) were calculated to estimate the strength of the association between H19 polymorphisms and cancer risk. Our findings revealed that the H19-rs217727 C>T polymorphism is significantly associated with an increased risk of overall cancer in homozygous codominant (OR=1.28, 95% CI=1.04-1.57, P =0.020, TT vs CC), dominant (OR=1.20, 95% CI=1.04-1.37, P =0.010, CT+TT vs CC), recessive (OR=1.21, 95% CI=1.00-1.46, P =0.048, TT vs CT+CC), and allele (OR=1.16, 95% CI=1.05-1.28, P =0.003, T vs C) genetic models. No significant correlations were observed between H19: rs2839698 G>A, rs2107425 C>T, rs2735971 C>T, rs3024270 G>C, rs3741219 T>C, rs2839701 C>G, rs2735469 C>T, rs17658052 G>A, and rs3741216 T>A polymorphisms and overall cancer risk. Stratified analysis by cancer type proposed that the rs217727 variant is associated with increased risk of oral squamous cell carcinoma (OSCC) and lung cancer, whereas the rs2839698 variant is associated with increased risk of gastrointestinal cancer. Taken together, these findings support an association between H19 rs217727, and rs2839698 polymorphisms and cancer susceptibility. Larger and well-designed studies are necessary to further confirm these findings in detail.