Dataset Information

Role of eIF3a in regulating cisplatin sensitivity and in translational control of nucleotide excision repair of nasopharyngeal carcinoma.

ABSTRACT: Translational control at the initiation step has been recognized as a major and important regulatory mechanism of gene expression. Eukaryotic initiation factor-3a (eIF3a), a putative subunit of the eIF3 complex, has recently been shown to have an important role in regulating the translation of a subset of mRNAs and is found to correlate with the prognosis of cancers. In this study, using nasopharyngeal carcinoma (NPC) cells as a model system, we tested the hypothesis that eIF3a negatively regulates the synthesis of nucleotide excision repair (NER) proteins, and, in turn, cellular response to treatments with DNA-damaging agents such as cisplatin (cis-dichlorodiammine platinum(II) (CDDP)). We found that a CDDP-sensitive sub-clone S16 isolated through limited dilution from an NPC cell line CNE-2 has increased eIF3a expression. Knocking down its expression in S16 cells increased cellular resistance to CDDP, NER activity and synthesis of the NER proteins XPA, XPC, RAD23B and RPA32. Altering eIF3a expression also changed the cellular response to CDDP and UV treatment in other NPC cell lines. Taken together, we conclude that eIF3a has an important role in the CDDP response and in NER activity of NPCs by suppressing the synthesis of NER proteins.

SUBMITTER: Liu RY

PROVIDER: S-EPMC3165083 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Role of eIF3a in regulating cisplatin sensitivity and in translational control of nucleotide excision repair of nasopharyngeal carcinoma.

Liu R-Y RY Dong Z Z Liu J J Yin J-Y JY Zhou L L Wu X X Yang Y Y Mo W W Huang W W Khoo S K SK Chen J J Petillo D D Teh B T BT Qian C-N CN Zhang J-T JT

Oncogene 20110530 48

Translational control at the initiation step has been recognized as a major and important regulatory mechanism of gene expression. Eukaryotic initiation factor-3a (eIF3a), a putative subunit of the eIF3 complex, has recently been shown to have an important role in regulating the translation of a subset of mRNAs and is found to correlate with the prognosis of cancers. In this study, using nasopharyngeal carcinoma (NPC) cells as a model system, we tested the hypothesis that eIF3a negatively regula ...[more]

PMID: 21625209

Similar Datasets

Project description:Background: Despite great advances in the diagnosis and treatment of non-small cell lung cancer (NSCLC), early diagnosis remains a challenge because patients usually have advanced lung cancer at the time they are diagnosed. The limited efficacy of conventional chemotherapy is another major problem in the treatment of NSCLC. Based on a published set of sequencing data, we find that hsa_circ_0001946 is a circRNA molecule with a significantly different expression level in three cell lines (human normal lung fibroblasts cell line MRC-5, human NSCLC cell line A549, cisplatin-resistant cell line A549/DDP), NSCLC tissues and paired adjacent normal tissues. We believe that hsa_circ_0001946 may have an effect on the progression of NSCLC and its sensitivity to cisplatin. Methods: We focused on investigating the circular RNA, hsa_circ_0001946. RNA interference of hsa_circ_0001946 was carried out in A549 cell lines to determine the effect of reduced hsa_circ_0001946 expression on lung cancer progression and was analyzed by Cell Counting Kit-8 (CCK-8), 5-ethynyl-20-deoxyuridine, clone formation, Hoechst, wound healing, and transwell assays. The nucleotide excision repair (NER) signaling pathway was identified by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Moreover, cellular responses to cisplatin were assessed through CCK-8 and flow cytometry assays. Western blot analysis and host-cell reactivation assay were used to determine the effect of hsa_circ_0001946 on NER signaling. Results: In this study, we found that the reduced expression of hsa_circ_0001946 promoted the viability, proliferation, migration, and invasion of NSCLC cells, as well as inhibition of cell apoptosis. Our findings suggest that hsa_circ_0001946 can affect the sensitivity of NSCLC cells to the chemotherapeutic drug cisplatin via modulation of the NER signaling pathway. Conclusions: Our study demonstrated the role of hsa_circ_0001946 in NSCLC pathogenesis, development, and chemosensitivity, and suggests that hsa_circ_0001946 may serve as a novel biomarker for the diagnosis and prediction of platinum-based chemosensitivity in patients with NSCLC.

Project description:Transcription-coupled nucleotide excision repair (TC-NER) is promptly triggered by 'local' elongating RNAP II molecules encountering DNA adducts such as cyclobutane pyrimidine dimers (CPD) induced by ultraviolet light and speeds up removing and repair in transcribed loci. Genome-wide measurements have revealed a dramatic shutdown of global transcription with a few exceptions of individual genes that are consequently highly upregulated by DNA damage. Deciphering the underlying mechanisms of the multifaceted transcriptional response always comprises one of the most fascinating frontiers in DNA repair research. Recent reports have revealed that persistent RNAP II initiation at the transcription start site of active regulatory regions with the continuous synthesis of start-RNAs guarantee sufficient scanning and repair of the whole transcribed genome, although transcription elongation drastically slows down shortly after genotoxic stress. Furthermore, a recent study found that RNA is extremely rapidly m6A methylated by METTL3 in response to UV irradiation which is crucial for recruitment of Pol k to DNA damage sites and subsequently mediates TC-NER. Together, these findings substantiate the molecular processes underlying the transcription-coordinated cellular response upon genotoxic stress might be more complex than previously believed. Unfortunately, all these findings merely focused on the early phase of recovery (within 4 hr after DNA damage). It remains to be determined how accessible chromatin reconfigures and regulates transcriptional programs in UV-induced DNA damage repair. It is also unclear whether the dynamics of gene expression are associated with other epigenomic reconstruction events such as global DNA methylation and demethylation. Moreover, the roles of internal messenger RNA modifications like N6-methyladenosine in TC-NER are poorly understood. Our integrative analyses provide a comprehensive view of the spatio-temporal chromatin configuration and epigenetic characterizations that accompanies TC-NER.

Dataset Information

Role of eIF3a in regulating cisplatin sensitivity and in translational control of nucleotide excision repair of nasopharyngeal carcinoma.

Publications

Role of eIF3a in regulating cisplatin sensitivity and in translational control of nucleotide excision repair of nasopharyngeal carcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets