Expression And Clinical Significance Of Autotaxin In Renal Cell Carcinoma And Bladder Carcinoma

Objective:Autotaxin (ATX) is present widely in normal tissue and tumor tissue as well as a variety of biological fluids, it participates in multiple physiological and pathological process, including cell growth and apoptosis, cell adhesion and angiogenesis, tumor invasion and metastasis, etc. Recently, a number of research have been carried out to study its structure and functions. In order to further understand the role of ATX in the development of renal cell carcinoma (RCC) and bladder carcinoma (BC), we investigated the expression and its clinical relevance of ATX in RCC and BC. This study may provide basic knowledge and methods for the early diagnosis and treatment of RCC and BC.Methods:70RCC and43BC samples of patients tissue and their adjacent normal tissue were collected. The immunohistochemical method was used to analyze the expression of ATX in all113samples. Image-ProPlus6.0software was employed to estimate the integrated optical density (IOD) of the immunohistochemical image, and the correlation of IOD and clinical features of RCC and BC were analyzed. Detection of ATX protein expression in RCC, BC and corresponding adjacent normal tissues was done by Western Blot, using ATX as primary antibody, and β-actin as an internal control. The membranes were hybridized with a secondary antibody conjugated with peroxidase and the chemo luminescent signal was detected using the enhanced check system with high performance chemiluminescence film. Expression levels of ATX protein were detected by ELISA from60cases of normal human and56cases of RCC patients and53cases BC patients collected peripheral blood serum. Lysophosphatidylcholine (LPC) as a substrate, the release of choline, quantitatively detect the serum lysophospholipase D (LysoPLD) enzyme activity of normal subjects, and RCC and BC patient group.Results:1、Autotaxin expression was significant upregulated in RCC, compared with RCC adjacent normal tissue (P<0.05). The IOD in the two groups were17079.28±3544.62and13158.77±4016.40, respectively.The expression of ATX had no relationship with clinical features, such as gender, age, tumor size (all P>0.05), but the clinical stages and pathological classification were associated with the increased level of ATX. ATX expression was significant upregulated in BC, compared with BC adjacent normal tissues (P<0.05).The IOD in the two groups was10833.41±1782.76and8952.63±1213.54, respectively.2、Western blot analysis results showed that the ATX protein expression in RCC tissue and adjacent normal tissue, with integrated absorbance value of65.76%±12.26%and46.74%±10.99%, respectively, The difference of expression level was statistically significant in RCC and adjacent normal tissue(P<0.05). ATX protein expression in BC tissue and adjacent normal tissue, with integrated absorbance value of41.05%±8.02%and51.77%±10.32%. The difference of ATX protein expression was statistically significant in BC and adjacent normal tissue (P<0.05).3、ELISA assay for the detection of concentrations of ATX in peripheral blood serum of RCC and BC and normal control group, the value were276.65±54.32ng/ml,268.27±44.07ng/ml and257.94±60.64ng/ml, respec-tively. BC group and RCC group compared with normal control group of this one value have no significant differences (all P>0.05).4、The lysoPLD enzyme activity in peripheral blood serum from RCC BC and normal control group were2.89±1.30nmol/(ml.min) and2.84±1.81nmol/(ml.min),2.52±1.71nmol/(ml.min) respectively. The lysoPLD activity a little higher in RCC and BC patients than in normal control group and the differences were not statistically significant (all P>0.05).Conclusion:1、Autotaxin expression is higher in RCC and BC compared with adjacent normal tissues.This study indicates that ATX protein are closely related with occurrence and development of RCC and BC.2、ATX expression is not correlated to the clinical characters such as age, sex, tumor size, but it is correlated with clinical stages and pathological classification. ATX protein expression level is correlated to the degree of malignancy in RCC. 3、RCC and BC patients have a little higher peripheral blood serum of lysoLPD activity than normal group, and the ATX protein concentration also increased, but not statistically significant. This study may provide basic knowledge for the early diagnosis of RCC and BC.