ABSTRACT
RBM10 regulates the expression of various genes, which are often mutated in male lung adenocarcinoma. The present study confirmed the association of the RBM10 mutation at exon 10 with the clinicopathological data and prognosis of lung adenocarcinoma. The effect of mutant RBM10 on regulating lung cancer cell growth and invasion was investigated in vitro. Tissue specimens from 50 patients with lung adenocarcinoma were subjected to Sanger sequencing for RBM10 exon 10 mutations. Lung adenocarcinoma cells were transfected with pcDNA3.1 carrying wild type RBM10 cDNA or exon mutation cDNA for cell viability, apoptosis and invasion assays. RBM10 exon 10 mutations were identified in 11 out of 50 patients, with a high frequency in male patients [c.763 C>T, p.Arg241Cys for 33.3% (10/30)] and were significantly associated with the American Joint Committee on Cancer stage (P=0.005), lymph node metastasis (P=0.019) and shorter 5-year survival rate compared with the wild type RBM10 (36.4% vs. 46.5%; P=0.019). Multivariate analysis revealed that RBM10 exon 10 mutation was an independent prognostic factor (HR=3.787; P=0.033). RBM10 exon 10 mutation at c.763 C>T significantly promoted tumor cell proliferation and invasion capacity, whereas wild type RBM10 inhibited tumor cell invasion in vitro. In conclusion, RBM 10 mutation at exon 10 (c.763 C>T) occurs frequently and is an independent prognostic predictor in lung adenocarcinoma.
ABSTRACT
Lenalidomide is an immunomodulatory drug and possesses anti-angiogenic and immunomodulatory activities against multiple myeloma. The present study assessed the in vitro effect of lenalidomide combined with cisplatin on MDA-MB-231, a triple-negative breast cancer (TNBC) cell line and explored the underlying molecular mechanism of this combination. Cell viability, apoptosis and the protein expression of phosphorylated (p) and total extracellular signal-regulated kinase (ERK), B-cell lymphoma-2 (Bcl-2), caspase-3, cleaved poly-adenosine diphosphate-ribose polymerase (cPARP), vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) were measured in MDA-MB-231 cells treated with different concentrations of lenalidomide, cisplatin and their combination using different biochemical assays. Lenalidomide demonstrated no significant effect on the cell viability of MDA-MB-231 cells, even at high concentrations, whereas lenalidomide in combination with cisplatin, significantly reduced cisplatin IC50 from 7.8 to 3.0 µM in MDA-MB-231 cells. In addition, lenalidomide and cisplatin in combination significantly induced cell apoptosis by 1.6- and 1.38-fold, respectively compared with lenalidomide and cisplatin alone (P<0.05). The expression levels of VEGF, bFGF and Bcl-2 proteins were significantly reduced (P<0.01), whereas caspase-3 and cleaved PARP expression were significantly increased in MDA-MB-231 cells treated with the combination compared to those treated with single agents (P<0.01). Lenalidomide treatment alone significantly reduced the p-ERK level compared with the control (P<0.05) and cisplatin treatment alone significantly increased it (P<0.01), however treatment with them in combination significantly reduced the p-ERK level in MDA-MB-231 cells compared with cisplatin treatment alone (P<0.05). In conclusion, the present study provides the basis for using lenalidomide in combination with cisplatin in TNBC therapy.
