MicroRNA-1 induces apoptosis by targeting prothymosin alpha in nasopharyngeal carcinoma cells
Journal
Journal of Biomedical Science
Journal Volume
18
Journal Issue
1
Pages
80
Date Issued
2011
Author(s)
Abstract
Background: MiR-1 (microRNA-1) has been used as a positive control in some microRNA experiments. We found that miR-1 transfection of nasopharyngeal carcinoma cells reveals a typical apoptotic process as shown by time-lapse microscopy so we investigated the mechanisms of miR-1 inducing apoptosis. Methods. To confirm that miR-1 induces apoptosis, we used Annexin V and TUNEL staining and caspase assay. To determine that miR-1 directly targets genes that involve in apoptosis, we analyzed microRNA and pathway databases, and cDNA expression microarrays from miR-1 transfected cells. To demonstrate candidate miR-1 targeted genes, we used qRT-PCR analysis and luciferase reporter vector assays. To assess the miR-1 target gene PTMA (prothymosin alpha, ProTalpha) involves in apoptosis, we used PTMA siRNA to knock down PTMA. Results: Annexin V and TUNEL staining and caspase assay confirm that miR-1 induces nasopharyngeal carcinoma cell apoptosis. MiR-1 transfection of HeLa, Cal-27, KYSE30 and NPC-TW06 cell lines which express low levels of endogenous miR-1 also induces apoptosis. However, miR-1 transfection of cell lines such as SW620, HepG2, HEK-293T, SAS and PC-13 which express high levels of endogenous miR-1 does not result in apoptosis. MiR-1 directly targets PTMA gene. PTMA siRNA and miR-1 accelerate the apoptotic process in cells treated with apoptosis inducers. Conclusions: The exogenous expression of miR-1 induces apoptosis in a number of cell lines. This is a model of microRNA-induced cell apoptosis. The PTMA is one of miR-1 target genes which involve in miR-1 inducing apoptosis. The apoptotic inducers including actinomycin D, camptothecin and etoposide are also the chemotherapeutic drugs in clinical cancer therapy and PTMA siRNA can accelerate apoptotic progression in cells treated with those apoptosis inducers. Therefore PTMA siRNA may have potential applications as an adjuvant in cancer chemotherapy. ? 2011 Wu et al; licensee BioMed Central Ltd.
Subjects
apoptosis; microRNA-1 (miR-1); nasopharyngeal carcinoma (NPC); ProTalpha); PTMA (prothymosin alpha
SDGs
Other Subjects
camptothecin; caspase; complementary DNA; dactinomycin; etoposide; lipocortin 5; luciferase; microRNA; microRNA 1; prothymosin alpha; small interfering RNA; unclassified drug; drug derivative; microRNA; MIRN1 microRNA, human; protein precursor; prothymosin alpha; thymosin; apoptosis; article; cancer cell culture; cell strain HEK293; cell strain HepG2; controlled study; enzyme assay; gene expression; gene targeting; genetic transfection; HeLa cell; human; human cell; microarray analysis; nasopharynx carcinoma; nick end labeling; nucleotide sequence; priority journal; quantitative analysis; real time polymerase chain reaction; signal transduction; genetics; metabolism; nasopharynx carcinoma; nasopharynx tumor; pathology; tumor cell line; Apoptosis; Cell Line, Tumor; Humans; MicroRNAs; Nasopharyngeal Neoplasms; Protein Precursors; Thymosin; Transfection
Type
journal article