Clinical significance of IGFBP2 and ERK1/2 expression in clear cell renal cell carcinoma
Lyu Jianzhi1, Cao Jinghe2, Liu Huan1, Wang Xinzhe1, Shi Susu1, Zhu Haizhou1,3
1Clinical Medical College, Jining Medical University, Jining 272013, China; 2Department of Reproductive Medicine, 3Department of Urology, Affiliated Hospital of Jining Medical University, Jining 272029, China
Abstract：ObjectiveTo explore the expression and clinical significance of IGFBP2 and ERK1/2 in the clear cell renal cell carcinoma (ccRCC). MethodsClinical data of 174 ccRCC patients who underwent surgical treatment in the Department of Urology, Affiliated Hospital of Jining Medical University from June 2017 to April 2019 were selected, and the blood samples of 30 healthy individuals were selected in the Health Examination Center during the same period. The expressions of IGFBP2 and ERK1/2 in ccRCC and adjacent (2cm from the edge of the tumor) tissues were assessed by immunohistochemistry and the correlation with clinical stage, histological grade and tumour size was analyzed. Serum levels of IGFBP2, ERK1 and ERK2 were also measured by ELISA in ccRCC patients and healthy controls. ResultsThe positive ratios of IGFBP2 and ERK1/2 expression in ccRCC tissues (87.93%, 80.46%) were higher than those in precancerous tissues (6.67%, 10.00%), all of which were significantly different (χ2=92.59, 65.87, all P＜0.01). The positive ratios of IGFBP2 and ERK1/2 expression in tumors larger than 4cm were higher than those in tumors smaller than 4cm, all of which were statistically significant (χ2=7.81, 13.02, all P＜0.05). There were no significant differences in the expression of IGFBP2 and ERK1/2 at patients′ age (χ2=0.78, 0.60), gender (χ2=0.05, 1.33), or tumor location (χ2=0.96, 0.57) (all P＞0.05). The positive expression rates of IGFBP2 and ERK1/2 increased with higher clinical stage and histological grade, and were statistically significant between groups in different grades (Z=-8.17, -3.80, all P＜0.05) and different stages（Z=-5.63，-9.94， all P＜0.05）. The expression of IGFBP2 was significantly positively correlated with ERK1/2 in ccRCC tissues (r=0.32, P＜0.05). ELISA showed that IGFBP2, ERK1, ERK2 were significantly increased in ccRCC patients ［(858.33±132.89)μg/L, (12.49±1.22)μg/L, (153.61±33.37)ng/L］ compared with healthy controls ［(267.65±86.56)μg/L, (8.69±1.80)μg/L, (105.63±12.03)ng/L］, all of which were significantly different (t=11.78, 5.53, 4.28, all P＜0.05). ConclusionThe expressions of IGFBP2 and ERK1/2 are elevated in serum and tumor tissues in ccRCC patients, and their positive expressions in tumor tissues are correlated with histological grade, clinical stage, and tumor size, the histological grade, later clinical stage, and larger tumor volume, the higher the positive expression rates of both suggesting that both may play a synergistic role in tumor progression.
