LncRNA RP3-326I13.1 promotes cisplatin resistance in lung adenocarcinoma by binding to HSP90B and upregulating MMP13.

Cisplatin (DDP) resistance has become the major obstacle in the therapy of malignant tumors, including lung adenocarcinoma (LAD). Long non-coding RNAs (lncRNAs) were confirmed to be related to DDP-resistance. Studies have shown that RP3-326I13.1 (also known as PINCR) could promote the progression of colorectal cancer, and RP3-326I13.1 knockdown could induce hypersensitivity to chemotherapy drugs. While the function of RP3-326I13.1 in LAD is unclear, therefore, this study aimed to research the biological function and related molecular mechanisms of RP3-326I13.1 in DDP-resistance of LAD. QPCR analysis found that RP3-326I13.1 was highly expressed in A549/DDP cells and LAD tissues. Cytological assays found that RP3-326I13.1 pro-moted the proliferation, migration, invasion, and DDP-resistance of LAD cell lines. Moreover, knock-down of RP3-326I13.1 could induce G1 phase arrest. Nude mouse xenograft assay confirmed that RP3-326I13.1 could promote tumor growth and DDP-resistance in vivo. Mechanically, RNA pull-down and mass spectrometry analysis indicated that heat shock protein HSP 90-beta (HSP90B) could be combined with RP3-326I13.1. HSP90B knockdown inhibited the effect of RP3-326I13.1 on proliferation, invasion, and promoted LAD cell lines apoptosis. Transcriptome sequencing analysis found that MMP13 was the downstream mRNA of RP3-326I13.1. In conclusion, RP3-326I13.1 could promote DDP-resistance of LAD by binding to HSP90B and upregulating human matrix metalloproteinase-13 (MMP-13) and may serve as a therapeutic target, as well as a biomarker for predicting DDP-resistance in LAD.Abbreviations:DDP: Cisplatin; LAD: Lung adenocarcinoma; LncRNAs: Long non-coding RNAs; qPCR: real-time fluorescent quantitative PCR; HSP90B: Heat shock protein HSP 90-beta; RPMI: Roswell Park Memorial Institute; FBS: Fetal bovine serum; CT: computed tomography; MRI: magnetic resonance imaging; RECIST: Response evaluation criteria in solid tumors; NC: Negative control; OE: overexpression; shRNA: short hairpin RNA; siRNA: small interfering RNA; CCK-8: Cell Counting Kit-8; IC50: The half maximal inhibitory concentration; PBS: Phosphate buffer saline; PI: propidium iodide; SDS-PAGE: sodiumdodecylsulfate-polyacrylamide gel electrophoresis; ceRNA: Competing endogenous RNA; HE: hematoxylin-eosin; ns: no significance.