The novel long non-coding RNA PANCR: A p53 activator and potential breast cancer biomarkers

Autor: Hongyan Ling, Deliang Cao, Yu Cao
Rok vydání: 2017
Předmět:
Zdroj: Journal of Clinical Oncology. 35:e23016-e23016
ISSN: 1527-7755
0732-183X
Popis: e23016 Background: Long non-coding RNAs (LncRNAs) may serve as a biomarker and potential therapeutic target of cancers. Chromosome 16q22.1 is frequently deleted in breast cancer and may contribute to breast carcinogenesis by inactivation of tumor suppressor genes. This study characterized a new LncRNA tumor suppressor in this region, named p53 activating non-coding RNA (PANCR). This LncRNA consists of 1.5kb in length. Methods: Quantitative real-time PCR was used for examine the PANCR expression in breast cancer tissues. RNA-pull down and RNA-Immunopreicitation were used to analyze PANCR targeted protein. Results: Our data showed that PANCR was downregulated in breast cancer cell lines and tissues. In the breast cancer cell lines, PANCR expression appeared reversely correlated with cell malignancy, and in breast cancer tissues, PANCR was downregulated over 2 times in 31(62.0%) of 50 cases compared to adjacent normal breast tissues. In breast cancer cells MCF7 and immortalized human mammary epithelial cells MCF10A, ectopic expression of PANCR induced marked apoptosis, suppressing cell proliferation in culture and tumor growth in xenografts, but in contrast, shRNA–mediated silencing of PANCR promoted cell growth and proliferation. Mechanistic approaches revealed that in both MCF7 and MCF10A cell, PANCR activated p53 and upregulated pro-apoptotic proteins bid and bim and cell cycle inhibitors p21waf/cip1 and p27Kip1. We further found that the PANCR binds to and activates p53 by dissociating the p53-MDM2 complex. We further characterized the functional domain of PANCR that interacts with p53. Conclusions: The LncRNA PANCR located in the deleted Chromosome 16q22.1 region is a novel intracellular p53 activator and tumor suppressor, which may be used as a target for cancer therapy through mimicking its binding domain and activation of p53.
Databáze: OpenAIRE