High miR-143 Expression Research Articles

KRAS Promoter Methylation Status and miR-18a-3p and miR-143 Expression in Patients With Wild-type KRAS Gene in Colorectal Cancer.

Although some mutations of KRAS proto-oncogene, GTPase (KRAS) have been associated with the prognosis and therapeutic management of colorectal cancer (CRC), the epigenetic mechanisms (DNA methylation and microRNA expression) that regulate wild-type KRAS expression in patients with CRC are poorly known. The aim of this study was to establish whether there is a relationship between the expression of the wild-type KRAS gene, the methylation status of its distal promoter, and miR-143 and miR-18a-3p levels in samples of sporadic CRC. A total of 51 cases of sporadic CRC with wild-type KRAS were analyzed. The expression levels of KRAS mRNA, miR-18a-3p, miR-143, and KRAS protein, as well as methylation in the distal promoter of the KRAS gene were evaluated. In the analyzed cases, KRAS mRNA expression was detected in 51.1%; wild-type KRAS protein was found in the membrane in 31.4% and in the cytoplasm in 98% of cases. An inverse relationship of marginal significance was observed between miR-18a-3p and KRAS protein expression in the cytoplasm (odds ratio=0.14, 95% confidence interval=0.012-1.092; p=0.08). The methylation status of the distal promoter of KRAS at four CpG islands was analyzed in 30 cases (58.8%): partial methylation of the four CpG islands evaluated was observed in two cases (6.7%). In these cases, KRAS protein expression was not evidenced at the membrane level; miR-18a-3p expression was not detected either but high expression of miR-143 was observed. No association was found between the expression levels of KRAS mRNA, miR-18a-3p, miR-143 and methylation status. Methylation status was detected with low frequency, thus being the first report of methylation in wild-type KRAS.

MiR-143 Targets ERK5 in Granulopoiesis and Predicts Outcome of Patients with Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a very heterogeneous disease of the hematopoietic system which is characterized by a fast progress with poor survival options. Despite intensive research standard treatment strategies rely since decades on the same chemotherapeutics, and the overall survival options still remain poor.In recent years, there is an emerging role of microRNAs (miRNAs) in the regulation of cancer development and resistance to cancer therapies. Mechanistically, miRNAs regulate gene expression through modulation of multiple target mRNAs by mRNA degradation or block of translation. It is shown that miRNAs can act as tumor suppressors and oncogenes dependent on the type of cancer. The miRNA-143/145 cluster is shown to be down-regulated in most cancers and is able to modulate tumorigenesis by targeting tumor associated genes. Several miR-143/145 targets are well described oncogenes, such as ERK5, DNMT3A or Bcl2. Interestingly, recent studies showed that the miR-143/145 cluster can regulate multidrug resistance proteins (MDR) in various cancer types and that enforced expression of miR-143/145 leads to increased sensitivity to various drugs. Besides its well-studied function mainly in solid tumors the role of the miR-143/145 cluster or miR-143 alone especially in the hematopoietic system remains largely unknown.In this study, we report a previously unrecognized function of miR-143 in granulopoiesis. Based on our observation that hematopoietic cells undergoing granulocytic differentiation exhibit increased miR-143 expression, we show that the absence of miR-143 in mice results in a reduced number of mature granulocytes but not monocytes in blood and bone marrow. Additionally, we show that overexpression or ablation of miR-143 resulted in accelerated granulocytic differentiation or block of differentiation in several in vitro systems, including leukemic cell lines and G-CSF treated CD34+ HSPCs, respectively.To identify the mRNA targets affected by miR-143 in hematopoietic cells we performed Argonaut2-RNA-Immunoprecipitation coupled with next generation sequencing. Here we could demonstrate a strong enrichment of members of the MAPK- and mTOR-pathways in cells overexpressing miR-143. Besides several potential targets of miR-143 we found ERK5 as particularly interesting since ERK5 was found to be a central mediator of cell survival, proliferation, motility, differentiation and apoptotic regulation of normal cells. To test whether miR-143 overexpression would also affect ERK5 protein abundance we performed western blot analysis of ERK5 and activated ERK5 in hematopoietic cells infected with miR-143 O/E constructs. Here we could show that miR-143 leads to reduced ERK5 protein levels in these cells. Since deregulation of both factors miR-143 as well as ERK5 have been implicated in the response to chemotherapeutic agents we analyzed the impact of miR-143 expression on treatment response. Here we show that AML patients receiving 5-azacytidine (Vidaza) and respond to the therapy had significant higher miR-143 levels than patients which did not respond. To test whether miR-143 expression would affect the response to chemotherapeutics, we overexpressed miR-143 in leukemic cells followed by Vidaza and AC220 treatment. Our results show a significant increase of apoptosis in cells overexpressing miR-143. Finally, we observed an association of high miR-143 expression levels with a higher probability of survival in two different cohorts of patients with acute myeloid leukemia. Taken together, we identified miR-143 as a relevant factor in granulocytic differentiation, which expression may be useful as prognostic factor and as new target for therapeutic strategies in AML. DisclosuresSchwind:Novartis: Consultancy.

Clinical relevance of miR-143 expression in ER-positive breast cancer patients.

e12574 Background: MicroRNA-143(miR-143) is a well-known tumor suppressive microRNA in various malignancies, including breast cancer. Recently, the tumor immune microenvironment has been reported to associate with progression of breast cancers. However, the association with the tumor immune microenvironment and miR-143 in breast cancers remains ambiguous. Given these backgrounds, we hypothesized that high expression of miR-143 is associated with favorable effect to the tumor immune microenvironment which leads to better survival of ER positive breast cancer patients. Methods: Two major publicly available breast cancer cohorts were used for this study. A total of 753 patients from The Cancer Genome Atlas (TCGA) and total of 1283 patients from Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) were used. Results: We defined the higher quartile of miR-143 expression levels as high and the remainder as low expression groups. There was no significant difference in patient clinicopathlogical features between two groups. Gene set enrichment analysis (GSEA) revealed that miR-143 high expression tumors enriched Helper T cell type 1 (Th1) related gene sets indicating the upregulation of anti-cancer immune cells. Also, the cell composition of anti-cancer immune cells, such as Th1 and Macrophage M1 were higher with miR-143 high tumors (p < 0.001 and p < 0.01 respectively) in whole group. On the contrary, pro-cancer immune cells such as Th2 and M1 were lower with miR-143 high tumors (p < 0.01 and p < 0.001 respectively) in whole group. Interestingly, among the subtypes, we found that ER positive subgroup followed this trend of high infiltration rate of anti-cancer immune cells and low infiltration rate of pro-cancer immune cells. Furthermore, only ER positive subgroup demonstrated the survival benefit with miR-143 high expression tumors. Conclusions: We demonstrated that high expression of miR-143 in ER breast cancer associate with favorable tumor immune microenvironment, upregulation of the anti-cancer immune cells and suppression of the pro-cancer immune cells, and associate with better survival of the breast cancer patients.

High Expression of microRNA-143 is Associated with Favorable Tumor Immune Microenvironment and Better Survival in Estrogen Receptor Positive Breast Cancer.

microRNA-143 (miR-143) is a well-known tumor suppressive microRNA that exhibits anti-tumoral function by targeting KRAS signaling pathways in various malignancies. We hypothesized that miR-143 suppresses breast cancer progression by targeting KRAS and its effector molecules. We further hypothesized that high expression of miR-143 is associated with a favorable tumor immune microenvironment of estrogen receptor (ER)-positive breast cancer patients which result in improved survival. Two major publicly available breast cancer cohorts; The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) were used. The miR-143 high expression group was associated with increased infiltration of anti-cancer immune cells and decreased pro-cancer immune cells, as well as enrichment of the genes relating to T helper (Th1) cells resulting in improved overall survival (OS) in ER-positive breast cancer patients. To the best of our knowledge, this is the first study to demonstrate that high expression of miR-143 in cancer cells associates with a favorable tumor immune microenvironment, upregulation of anti-cancer immune cells, and suppression of the pro-cancer immune cells, associating with better survival of the breast cancer patients.

Abstract P3-08-59: High expression microRNA-143 is associated with favorable tumor immune microenvironment and better survival of ER positive breast cancer patients

Abstract Background: MicroRNA-143(miR-143) is known to function as the tumor suppressor in various cancers, including breast cancer. The tumor immune microenvironment such as the balance between the T helper cell type 1 (Th1) and Th2 is reported to associate with the survival of the breast cancer patients. In this study, we hypothesized that the miR-143 has favorable effect to the tumor immune microenvironment. Material and Methods: We obtained the clinicopathological data and survival information of 755 breast cancer patients from The Cancer Genome Atlas (TCGA) database. Survival analysis, Overall survival (OS) and Disease free survival (DFS) was conducted comparing the high and low expression groups. CYT score, CIBERSORT, and other immunological factors were used to evaluate intratumoral immune cell composition within estrogen receptor (ER) positive breast cancer patients. Also, gene set enrichment analysis (GSEA) was performed between miR-143 high and low expression groups within the ER positive group. Results: High expression of miR-143 was significantly associated with prolonged OS only in ER positive breast cancer patients (p=0.014). Expression of miR-143 was not associated with DFS, stage, TNM factors of breast cancer patients. Within ER positive patients, the result of CIBERSORT revealed that high expression of miR-143 was associated with higher percentage of macrophage M1 (p<0.03) and lower percentage of macrophage M2 (p<0.001). There was more Th1 cells in miR-143 high group (p<0.001) whereas Th2 cells were less (p<0.001). This result was strikingly echoed by GSEA, where miR-143 high significantly enriched the genes related to Th1 cells compared with that of Th2 cells. Regulatory T cell, Lymphocyte infiltration signature score, and T cell receptor diversity were higher in the patients with high miR-143 expression (p<0.03, p<0.001, and p<0.001 respectively). CYT score that reflect cytolytic activity was higher in the high miR-143 expression group (p<0.04). Conclusion: High expression of miR-143 was associated with improved OS in ER positive breast cancer patients. Also, miR-143 was found to associate with high Th1 and low Th2 cells as well as enriching the genes relating to Th1 cells, which may explain the favorable role of miR-143 in ER positive breast cancer. Citation Format: Yoshihisa Tokumaru, Masanori Oshi, Mariko Asaoka, Takashi Takeshita, Eriko Katsuta, Manabu Futamura, Kazuhiro Yoshida, Kazuaki Takabe. High expression microRNA-143 is associated with favorable tumor immune microenvironment and better survival of ER positive breast cancer patients [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-08-59.

Clinical Features and MicroRNA Expression Patterns Between AML Patients With DNMT3A R882 and Frameshift Mutations.

Background: DNA methyltransferase 3A (DNMT3A) plays a unique role in hematopoiesis and acute myeloid leukemia (AML) pathogenesis. While the influences of DNMT3A mutation subtypes are still under debate.Purpose: Exploration of the clinical and molecular differences between AML patients carrying DNMT3A R882 mutations and DNMT3A frameshift mutations.Methods: Next generation of sequencing (NGS) and clinical data of 118 AML patients in our center were analyzed and compared. NGS, mRNA and miRNA profiling and clinical data from 12 patients in TCGA database were integrative analyzed.Results: Among all patients enrolled, 113 patients were positive for the variants of interest. Overall, a total of 295 variants were discovered, among which 24 DNMT3A mutations were detected, including 1 non-sense, 20 missense, 3 frameshift mutations. And 7 DNMT3A R882 mutations (3 R882H, 2 R882C, and 2 R882P) were found. Clinical analysis from our cohort and TCGA database indicated that patients carrying DNMT3A R882 mutation exhibited significantly higher levels of peripheral blood hemoglobin and non-significantly inferior prognosis compared with patients with DNMT3A frameshift mutations. Integrative analysis indicated that miR-10b, miR-143, and miR-30a were significantly decreased in the DNMT3A R882 group. High miR-143 expression is significantly associated with better prognosis in AML patients with DNMT3A mutations.Conclusion: Different molecular and clinical characteristics existed between patients with DNMT3A variant subtypes. The distinct microRNA expression pattern for DNMT3A R882 AML patients might not only act as markers to predict disease prognosis, but also could be further investigated to develop novel therapeutic targets for patients with DNMT3A mutations.

Prognostic roles of microRNA 143 and microRNA 145 in colorectal cancer: A meta-analysis

A systematic analysis was conducted to clarify the relationship between miR-143/145 and the prognosis of colorectal cancer. We searched four databases: PubMed, EMBASE, Web of Science, and the Cochrane Library. We extracted and estimated the hazard ratios for survival outcomes, which compared low and high expression levels of miR-143/145 in colorectal cancer patients in the available studies. Each individual hazard ratio was used to calculate the pooled hazard ratio. A total of 17 articles including 5128 patients were ultimately included. The results showed that there was no significant difference between low expression and high expression of miR-143 in the overall survival of colon cancer patients. However, low expression of miR-143 was significantly associated with high event-free survival (hazard ratio (HR) 0.6; 95% confidence interval (CI) 0.40, 0.88). Low expression of miR-145 was associated with poor prognosis of patients (HR 1.92; 95% CI 1.45, 2.54); those with low expression of miR-145 were at 1.92-fold higher risk for short-term overall survival than those with high expression of miR-145. MiR-145 was an unfavorable factor for the prognosis of colorectal cancer. There were no significant differences between low expression of miR-145 and high expression of miR-143 in event-free survival. miR-143 and miR-145 have promising prognostic value for colorectal cancer. Low expression of miR-143 can predict high event-free survival, and low expression of miR-145 can predict poor overall survival.

MicroRNA-143 targets ERK5 in granulopoiesis and predicts outcome of patients with acute myeloid leukemia

Hematopoiesis, the formation of blood cells from hematopoietic stem cells (HSC), is a highly regulated process. Since the discovery of microRNAs (miRNAs), several studies have shown their significant role in the regulation of the hematopoietic system. Impaired expression of miRNAs leads to disrupted cellular pathways and in particular causes loss of hematopoietic ability. Here, we report a previously unrecognized function of miR-143 in granulopoiesis. Hematopoietic cells undergoing granulocytic differentiation exhibited increased miR-143 expression. Overexpression or ablation of miR-143 expression resulted in accelerated granulocytic differentiation or block of differentiation, respectively. The absence of miR-143 in mice resulted in a reduced number of mature granulocytes in blood and bone marrow. Additionally, we observed an association of high miR-143 expression levels with a higher probability of survival in two different cohorts of patients with acute myeloid leukemia (AML). Overexpression of miR-143 in AML cells impaired cell growth, partially induced differentiation, and caused apoptosis. Argonaute2-RNA-Immunoprecipitation assay revealed ERK5, a member of the MAPK-family, as a target of miR-143 in myeloid cells. Further, we observed an inverse correlation of miR-143 and ERK5 in primary AML patient samples, and in CD34+ HSPCs undergoing granulocytic differentiation and we confirmed functional relevance of ERK5 in myeloid cells. In conclusion, our data describe miR-143 as a relevant factor in granulocyte differentiation, whose expression may be useful as a prognostic and therapeutic factor in AML therapy.

MiR-143 regulates proliferation and apoptosis of myelocytic leukemia cell HL-60 via modulating ERK1.

Extracellular signal-regulated kinase (ERK)/mitogen activated protein kinase (MAPK) signaling pathway is widely involved in cell proliferation and invasion regulation. Enhanced expression or function of ERK1 is important for leukemia. Abnormal down-regulation of microRNA (miR)-143 is correlated with leukemia pathogenesis, indicating possible tumor-suppressing role. Bioinformatics analysis showed the existence of complementary binding sites between miR-143 and ERK1. This study aims to investigate whether the miR-143 plays a role in mediating ERK1 expression and proliferation and apoptosis of leukemia cells. Dual luciferase reporter gene assay confirmed targeted regulation between miR-143 and ERK1. Quantitative RT-PCR (qRT-PCR) was used to measure and compare the peripheral miR-143 and ERK1 expression between healthy and acute promyelocytic leukemia (APL) patients to analyze the effect of miR-143 and MEK1 on survival and prognosis. Cultured HL-60 cells were treated with miR-143 mimic or small interfering RNA (siRNA)-ERK1, followed by qRT-PCR to measure miR-143 expression. Western blot quantified expression of ERK1 and p-ERK1, flow cytometry measured apoptosis, and EdU staining measured proliferation. MiR-143 targeted and modulated ERK1. APL patients presented lower miR-143 and higher ERK1 in peripheral blood. Those with miR-143 down-regulation displayed worse prognosis than those with high miR-143 expression (χ2 = 5.198, p = 0.039). Patients with ERK1 mRNA low-expression presented better prognosis than those a having higher expression (Log-rank test, χ2 = 5.873, p = 0.028). Transfection of miR-143 mimic or siRNA-ERK1 remarkably suppressed ERK1 and p-ERK1 expression in HL-60 cells, inhibited cell proliferation and induced cell apoptosis. MiR-143 down-regulation and ERK1 up-regulation are correlated with APL pathogenesis. Their expression level affected patient's prognosis. MiR-143 targeted and inhibited ERK1 expression, weakened proliferation potency of HL-60 cells, and induced apoptosis.

MicroRNAs with prognostic significance in bladder cancer: a systematic review and meta-analysis

The aim of this study was to systematically review articles that investigated the prognostic significance of different microRNAs in bladder cancer (BC). We systematically searched PubMed, Web of Science, and Embase to identify relevant studies until March 2016. After screening, 26 studies that involved 2753 patients were included. Results suggested that many miRs expression aberration may predict prognosis in patients with BC. There are six miRs (miR-21, miR-143, miR-155, miR-200, miR-214, and miR-222) were reported by at least two studies, and we performed meta-analysis in the corresponding studies. Accordingly, we found that high miR-21 expression was associated with poor overall survival [OS; hazard ratio (HR) = 3.94, 95% CI 2.08–7.44]. High miR-143 expression was associated with poor progression-free survival (PFS; HR = 3.78, 95% CI 1.61–8.89). High miR-155 expression was associated with poor PFS (HR = 8.10, 95% CI 2.92–22.48). High miR-222 expression was associated with poor OS (HR = 3.39, 95% CI 1.10–10.41). Meanwhile, low miR-214 expression was correlated with poor RFS(HR = 0.34, 95% CI 0.22–0.53). Our comprehensive systematic review concluded that microRNAs, particularly miR-21, miR-143, miR-155, miR-214, and miR-222, could serve as meticulous follow-up markers for early detection of progression or recurrence and even useful therapeutic targets for the treatment in patients with BC.

Predictive value of microRNA-143 in evaluating the prognosis of patients with hepatocellular carcinoma.

The study aims to evaluate the predictive value of microRNA-143 (miR-143) for the prognosis of patients with hepatocellular carcinoma (HCC). Between October 2010 and October 2012, 131 HCC patients were selected as a case group; meanwhile, 122 healthy controls were enrolled as a control group. The miR-143 expression in serum was detected by quantitative real-time polymerase chain reaction (qRT-PCR). These HCC patients were divided into the high miR-143 expression group and the low miR-143 expression group based on the threshold of receiver operating characteristic (ROC) curve. Kaplan-Meier method was applied to analyze the prognosis of HCC patients. MiR-143 exhibited decreased expression in the case group significantly compared to the control group. The areas under the ROC curve (AUC), sensitivity value and specificity value of the miR-143 expression for the diagnosis of HCC were 0.831, 80.30% and 82.40%, respectively. The miR-143 expression was negatively correlated with vascular invasion, TNM staging, tumor recurrence, metastasis and survival of HCC patients. Our study provides evidence that miR-143 may be negatively correlated with the prognosis of HCC and provides a promising strategy for HCC treatment and prognosis improvement.

MicroRNA-143 is a putative predictive factor for the response to fluoropyrimidine-based chemotherapy in patients with metastatic colorectal cancer.

Approximately half of the colorectal cancer (CRC) patients develop metastatic disease. Fluoropyrimidine-based chemotherapy forms the backbone of treatment in these patients. However, the response to this therapy varies between individuals. Therefore, an important challenge in CRC research is to identify biomarkers that are predictive of this response. In this study, we explored the potential of miRNAs, and the miRNA producing protein Dicer, as biomarkers that can predict chemo-sensitivity to fluoropyrimidine chemotherapy in patients with metastatic colorectal cancer (mCRC). We analyzed the levels of 22 miRNAs and the Dicer protein in primary tumors from patients with mCRC who were treated with first-line capecitabine monotherapy within the CAIRO trial of the Dutch Colorectal Cancer Group. Correlation between the expression status of miRNAs or Dicer in primary tumors and the progression free survival (PFS) were investigated. Patients with low expression of miR-143 in their primary tumor had increased median PFS compared to those with high expression of miR-143. Furthermore, FXYD3, an ion transport regulator and a putative target of miR-143, also showed an association with PFS. These findings warrant further studies to investigate the relationship between miR-143, FXYD3 and fluoropyrimidines, and the clinical utility of miR-143 as biomarker.

The G-CSF Induced MiR-143 Targets MAPK-Family Proteins and Is a Prognostic Factor for RIC-Transplanted AML Patients

Acute myeloid leukemia (AML) is a heterogeneous clonal disorder of defective hematopoiesis of white blood cells and often characterized by limited treatment options and a poor prognosis. MicroRNAs, a class of small non-coding RNAs, have been reported over the last years to play an important role in the regulation of “normal” and pathological processes. By binding to the 3'UTR of their target mRNAs, microRNAs lead to the translational repression of their target gene. Deregulation of a certain microRNA thereby may lead to disrupted signal pathways, such as MAPK-signaling, and to tumorigenesis. However, the role of microRNAs in hematopoietic differentiation and blood cancer development remains largely unknown. In AML only few miRNAs are functionally characterized, and the clinical relevance of these miRNAs still remains to be determined. In this study we identified microRNA-143 (miR-143) to be highly upregulated in G-CSF stimulated CD34+ cells. We could also show the granulopoietic association of miR-143 in several hematopoietic cell line models. In addition, we show that miR-143 is upregulated in APL patients after ATRA treatment. QPCR analysis of pri-miR-143 expression in RIC (reduced intensity conditioning) transplanted AML patients reveal that high expression of miR-143 is associated with high event-free and overall survival. In functional studies, stable overexpression of miR-143 in K562-C/EBPα-p42 cells enhances the C/EBPalpha induced granulocytic differentiation significantly. In contrast, stable knock down of miR-143 reduced the ability of K562-C/EBPα-p42 cells to undergo granulocytic differentiation upon β-estradiol treatment. Moreover, chromatinimmunoprecipitation (ChIP) analysis show the direct binding of C/EBPα to the promoter region of miR-143. By in silico prediction, we found MAPK protein family members (MAPK1, MAPK3 and MAPK7) as predicted targets of miR-143. Western blot analysis of AML patient samples and G-CSF stimulated CD34+ cells clearly show an inverse correlation of miR-143 and MAPK7 (ERK5) protein expression. By transient overexpression of miR-143 we could show a strong downregulation of MAPK protein family member expression in NB4 cells. These studies suggest miR-143 as an essential factor in granulocytic differentiation driven by G-CSF. Deregulation of miR-143 may play an important role in the development of AML. Furthermore, we propose miR-143 as prognostic marker for AML patients undergoing RIC transplantation therapy. DisclosuresNo relevant conflicts of interest to declare.

MicroRNA‐143 regulates collagen type III expression in stromal fibroblasts of scirrhous type gastric cancer

Gastric cancer (GC) is one of the most common malignancies worldwide. In particular, scirrhous type GC is highly metastatic and is characterized clinically by rapid disease progression and poor prognosis. MicroRNAs (miRNAs) play crucial roles in cancer development and progression. In the present study, we identified several miRNAs that are expressed at higher levels in scirrhous type GC than in non-scirrhous type GC by miRNA microarray analysis. Among these, microRNA-143 (miR-143) expression was higher in scirrhous type GC than in non-scirrhous types of GC. In situ hybridization and quantitative RT-PCR analysis showed that miR-143 is expressed by stromal fibroblasts but not by cancer cells. In stromal cells, miR-143 enhanced collagen type III expression in normal gastric fibroblasts and cancer-associated fibroblasts through activation of transforming growth factor-β)/SMAD signaling. Furthermore, high miR-143 expression in GC was associated with worse cancer-specific mortality (P = 0.0141). Multivariate analysis revealed that miR-143 was an independent prognostic factor. Treatment of GC cell lines with 5-aza-2′-deoxycytidine restored the expression of miR-143, and precursor miR-143 caused the inhibition of cancer cell invasion. These data suggest that miR-143 regulates fibrosis of scirrhous type GC through induction of collagen expression in stromal fibroblasts and that miR-143 expression serves as a prognostic marker of GC.

Abstract 4197: Function of microRNA-143 and its potential of prognostic factor in scirrhous type gastric cancer.

Abstract Gastric cancer (GC) is one of the most common malignancies worldwide. Scirrhous type GC is highly metastatic and characterized clinically by rapid disease progression and poor prognosis. MicroRNAs (miRNAs), small non-coding RNA of 19-25 nucleotides, play a part in crucial biological processes and also have an important role in cancer development and progression. In the present study, we show that microRNA-143 (miR-143) is expressed at higher level in diffuse type GC than in intestinal type GC by microRNA microarray analysis. We investigated whether miR-143 is useful as a diagnostic marker of scirrhous type GC. Quantitative RT-PCR analysis revealed that miR-143 expression was low in GC in comparison with adjacent non-tumorous mucosa. Expression levels of miR-143 were higher in scirrhous type GC than those in other types of GC. Treatment of 5-aza-2′-deoxycytidine retrieved miR-143 expression, suggesting that miR-143 might be repressed by DNA methylation. Quantitative RT-PCR and in situ hybridization analysis showed that miR-143 is expressed at higher level in normal fibroblast and cancer associated fibroblast cell lines than in GC cell lines, indicating that major source of miR-143 in cancer tissue is stromal fibroblasts rather than cancer cells. miR-143 knock down by RNAi repressed collagen type III expression in normal fibroblast and cancer associated fibroblast cell lines. Furthermore, TGF-β treatment induced expression of miR-143 and collagen type III mRNA, and this induction of collagen type III mRNA was repressed by miR-143 knock down. We also studied the relation of miR-143 expression with GC patient prognosis (n=68). High miR-143 expression was associated with worse prognosis (P=0.0141). These data suggest that miR-143 regulates fibrosis of scirrhous type GC through induction of collagen expression in stromal fibroblasts and miR-143 expression is a prognostic marker of GC. Citation Format: Yutaka Naito, Naoya Sakamoto, Naohiro Uraoka, Kazuhiro Sentani, Naohide Oue, Masakazu Yashiro, Kosei Hirakawa, Wataru Yasui. Function of microRNA-143 and its potential of prognostic factor in scirrhous type gastric cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4197. doi:10.1158/1538-7445.AM2013-4197