The expression level of CSDAP1 in lung cancer and its clinical significance

Abstract

Expression level of messenger RNA (mRNA) of cold shock domain protein A intronless pseudogene (CSDAP1) in lung cancer tissues was studied. Fresh pathological specimens collected from 317 patients with primary lung cancer through surgical resection from January 2007 to January 2012 were selected. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis were used to detect the transcription and translation of CSDAP1 in lung cancer tissues and cancer-adjacent normal tissues, and the results were analyzed in combination with clinicopathological features and prognosis of lung cancer. Among 317 lung cancer specimens, 105 cases (33.1%) had high expression of CSDAP1. Among 138 cases of pulmonary adenocarcinoma, 59 cases had high expression of CSDAP1, and the high expression rate was 42.8%. Among 170 cases of lung squamous cell carcinoma, 46 cases had high expression of CSDAP1, and the high expression rate was 27.5% (P<0.05). Three cases of large cell carcinoma and 9 cases of small cell carcinoma had extremely low expression or had no expression of CSDAP1. Among the 127 lung cancer patients with regional lymph node metastasis, 53 cases (41.7%) had high expression of CSDAP1, while among the 190 lung cancer patients without regional lymph node metastasis, 52 cases (27.4%) had high expression of CSDAP1 (P<0.05). The results also revealed that the expression of CSDAP1 was also related to tumor-node-metastasis (TNM) staging of lung cancer. One-year, three-year and five-year survival rates of lung cancer patients who had no expression of CSDAP1 were relatively high (P<0.05). The results suggested that CSDAP1 may play an important role in the occurrence, development and judgement of prognosis of lung cancer.

Keywords: CSDAP1; RT-PCR; clinical significance; lung cancer; western blot.

Figure 1.

Detection of CSDAP1 expressions in lung cancer cells with RT-PCR

Figure 2.

Detection of CSDA in lung cancer A549 and NCI-H446 cells by western blot analysis. Expression of CSDA in A549 and PC-9 was detected by western blot analysis and results showed that there was a significant difference in the expression of CSDA protein between the two groups of cells (t=9.517, P=0.001). *P<0.05.

Figure 3.

Comparison of activity of lung cancer A549 cells detected with MTT method. The results of MTT assay showed that viability of A549 cells treated with CSDAP1 was significantly higher than that of untreated A549 cells and A549 cells treated with GAPDH (untreated A549t=11.226, untreated A549 P=0.001; A549t treated with GAPDH=8.622, A549P treated with GAPDH=0.001), and there was no statistical difference in viability of untreated A549 cells and GAPDH-treated A549 cells (t=1.146, P=0.615). *P<0.05; ^#P>0.05.

Figure 4.

Survival curve of patients with high expression of CSDAP1 and those with low expression of CSDAP1. Patients were divided into high expression group and low expression group according to the median expression level of CSDAP1 mRNA. Survival rate of patients with low expression was significantly higher than that of patients with high expression (P<0.001).