Dataset Information

LncRNA H19 is a major mediator of doxorubicin chemoresistance in breast cancer cells through a cullin4A-MDR1 pathway.

ABSTRACT: Development of chemoresistance is a persistent problem during cancer treatment. Long non-coding RNAs (LncRNAs) are currently emerging as an integral functional component of the human genome and as critical regulators of cancer development and progression. In the present study, we investigated the role and molecular mechanism of H19 lncRNA in chemoresistance development by using doxorubicin (Dox) resistance in breast cancer cells as a model system. H19 lncRNA expression was significantly increased in anthracycline-treated and Dox-resistant MCF-7 breast cancer cells. This H19 overexpression was contributed to cancer cell resistance to anthracyclines and paclitaxel as knockdown of H19 lncRNA by a specific H19 shRNA in Dox-resistant cells significantly improved the cell sensitivity to anthracyclines and paclitaxel. Furthermore, gene expression profiling analysis revealed that a total of 192 genes were associated with H19-mediated Dox resistance. These genes were enriched in multiple KEGG pathways that are related to chemoresistance. Using genetic and pharmacological approaches, we demonstrated that MDR1 and MRP4 were major effectors of H19-regulated Dox resistance in breast cancer cells as MDR1 and MRP4 expression was markedly elevated in Dox-resistant cells while dramatically reduced when H19 was knocked down. Moreover, we found that CUL4A, an ubiquitin ligase component, was a critical factor bridging H19 lncRNA to MDR1 expression, and a high tumor CUL4A expression was associated with low survival in breast cancer patients treated with chemotherapy. These data suggest that H19 lncRNA plays a leading role in breast cancer chemoresistance, mediated mainly through a H19-CUL4A-ABCB1/MDR1 pathway.

SUBMITTER: Zhu QN

PROVIDER: S-EPMC5696158 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

LncRNA H19 is a major mediator of doxorubicin chemoresistance in breast cancer cells through a cullin4A-MDR1 pathway.

Zhu Qiong-Ni QN Wang Guo G Guo Ying Y Peng Yan Y Zhang Rui R Deng Jun-Li JL Li Zhi-Xing ZX Zhu Yuan-Shan YS

Oncotarget 20170921 54

Development of chemoresistance is a persistent problem during cancer treatment. Long non-coding RNAs (LncRNAs) are currently emerging as an integral functional component of the human genome and as critical regulators of cancer development and progression. In the present study, we investigated the role and molecular mechanism of H19 lncRNA in chemoresistance development by using doxorubicin (Dox) resistance in breast cancer cells as a model system. <i>H19</i> lncRNA expression was significantly i ...[more]

PMID: 29190892

Similar Datasets

Project description:Osteosarcoma is the most common type of pediatric bone tumor. Despite great advances in chemotherapy during the past decades, the survival rates of osteosarcoma patients remain unsatisfactory. Drug resistance is one of the main reasons, leading to treatment failure and poor prognosis. Previous reports correlated expression of cluster of differentiation 44 (CD44) with drug resistance and poor survival of osteosarcoma patients, however the underlying mechanisms are poorly defined. Here, we investigated the role of CD44 in the regulation of drug chemoresistance, using osteosarcoma cells isolated from mice carrying a mutation of the tumor suppressor neurofibromatosis type 2 (Nf2) gene. CD44 expression was knocked-down in the cells using CRISPR/Cas9 approach. Subsequently, CD44 isoforms and mutants were re-introduced to investigate CD44-dependent processes. Sensitivity to doxorubicin was analyzed in the osteosarcoma cells with modified CD44 expression by immunoblot, colony formation- and WST-1 assay. To dissect the molecular alterations induced by deletion of Cd44, RNA sequencing was performed on Cd44-positive and Cd44-negative primary osteosarcoma tissues isolated from Nf2-mutant mice. Subsequently, expression of candidate genes was evaluated by quantitative reverse transcription PCR (qRT-PCR). Our results indicate that CD44 increases the resistance of osteosarcoma cells to doxorubicin by up-regulating the levels of multidrug resistance (MDR) 1 protein expression, and suggest the role of proteolytically released CD44 intracellular domain, and hyaluronan interactions in this process. Moreover, high throughput sequencing analysis identified differential regulation of several apoptosis-related genes in Cd44-positive and -negative primary osteosarcomas, including p53 apoptosis effector related to PMP-22 (Perp). Deletion of Cd44 in osteosarcoma cells led to doxorubicin-dependent p53 activation and a profound increase in Perp mRNA expression. Overall, our results suggest that CD44 might be an important regulator of drug resistance and suggest that targeting CD44 can sensitize osteosarcoma to standard chemotherapy.

Project description:Long non-coding RNAs (lncRNAs) are involved in the pathology of various tumors, including colorectal cancer (CRC). The crosstalk between carcinoma- associated fibroblasts (CAFs) and cancer cells in the tumor microenvironment promotes tumor development and confers chemoresistance. In this study, we further investigated the underlying tumor-promoting roles of CAFs and the molecular mediators involved in these processes. Methods: The AOM/DSS-induced colitis-associated cancer (CAC) mouse model was established, and RNA sequencing was performed. Small interfering RNA (siRNA) sequences were used to knock down H19. Cell apoptosis was measured by flow cytometry. SW480 cells with H19 stably knocked down were used to establish a xenograft model. The indicated protein levels in xenograft tumor tissues were confirmed by immunohistochemistry assay, and cell apoptosis was analyzed by TUNEL apoptosis assay. RNA-FISH and immunofluorescence assays were performed to assess the expression of H19 in tumor stroma and cancer nests. The AldeRed ALDH detection assay was performed to detect intracellular aldehyde dehydrogenase (ALDH) enzyme activity. Isolated exosomes were identified by transmission electron microscopy, nanoparticle tracking and Western blotting. Results: H19 was highly expressed in the tumor tissues of CAC mice compared with the expression in normal colon tissues. The up-regulation of H19 was also confirmed in CRC patient samples at different tumor node metastasis (TNM) stages. Moreover, H19 was associated with the stemness of colorectal cancer stem cells (CSCs) in CRC specimens. H19 promoted the stemness of CSCs and increased the frequency of tumor-initiating cells. RNA-FISH showed higher expression of H19 in tumor stroma than in cancer nests. Of note, H19 was enriched in CAF-derived conditioned medium and exosomes, which in turn promoted the stemness of CSCs and the chemoresistance of CRC cells in vitro and in vivo. Furthermore, H19 activated the ?-catenin pathway via acting as a competing endogenous RNA sponge for miR-141 in CRC, while miR-141 significantly inhibited the stemness of CRC cells. Conclusion: CAFs promote the stemness and chemoresistance of CRC by transferring exosomal H19. H19 activated the ?-catenin pathway via acting as a competing endogenous RNA sponge for miR-141, while miR-141 inhibited the stemness of CRC cells. Our findings indicate that H19 expressed by CAFs of the colorectal tumor stroma contributes to tumor development and chemoresistance.

Project description:Increasing evidence has revealed close relationships between long non-coding RNAs (lncRNAs) and chemoresistance in multiple types of tumors; however, functional lncRNAs in breast cancer (BC) have not been completely identified. In this study, we aimed to identify novel lncRNAs that might play critical roles in doxorubicn resistance, which could reveal potential biomarkers of BC. Using a BC dataset (GSE81971), we identified 452 lncRNAs that were upregulated and 659 that were downregulated; furthermore, there were 1896 differentially expressed mRNAs, of which 1137 were upregulated and 758 were downregulated in MCF-7/ADR cells compared with the expression in MCF-7 cells. We constructed an lncRNA-mRNA network by integrating probe reannotation and regulatory interactions. To elucidate the key lncRNAs in BC, we further analyzed dysregulated lncRNA-mRNA crosstalk, and six candidate lncRNAs (lnc-TRDMT1-5, ZNF667-AS1, lnc-MPPE1-13, DSCAM-AS1:5, DSCAM-AS1:2, and lnc-CFI-3) were identified. Notably, the expression level of lnc-TRDMT1-5 was significantly upregulated in resistant cells compared with sensitive cells, and its levels were increased in BC tissues compared with adjacent tissues. Levels were positively associated with estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) expression levels. High expression of lnc-TRDMT1-5 predicted poor prognosis in ER-positve and HER2-positive BC patients, especially in patients with chemoresistance. Bioinformatic and functional analysis revealed that lnc-TRDMT1-5 was involved in many crucial pathways in cancer, such as the PI3K/AKT and Wnt signaling pathways. Subcellular localization predicted that lnc-TRDMT1-5 was located in the cytoplasm, and the lncRNA-miRNA-mRNA network showed that lnc-TRDMT1-5 might serve as a regulator in BC. Here, our results demonstrated a dysregulated lncRNA-mRNA network that might provide new treatment strategies for chemoresistant BC, and the results identified a new lncRNA, lnc-TRDMT1-5, with oncogenic and prognostic functions in human BC.

Dataset Information

LncRNA H19 is a major mediator of doxorubicin chemoresistance in breast cancer cells through a cullin4A-MDR1 pathway.

Publications

LncRNA H19 is a major mediator of doxorubicin chemoresistance in breast cancer cells through a cullin4A-MDR1 pathway.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets