The Study On Expression Patterns Of ANXA1/ANXA4/CA1 At The Different Clinical Stages Of CRC

[Background and objective]Nowadays, colorectal cancer (CRC) is a serious public health problem. Because of the lack of specific marker for early diagnosis and treatment target, the clinical effect of combined treatment is not very ideal. In order to identify cancer marker group with high sensitivity and specificity contributing to early diagnosis, try to make clear what is the differential molecular network during the every development stages of CRC, and according to the molecule network, try to establish the molecule classifications, in our previous study, the differential molecules in different clinical stages of CRC was identified using proteomic analysis combined with cDNA microarray. We found the expression of ANXA1, ANXA4 and CA1 in protein level was consistent with transcription level, suggesting these molecules maybe play important role in CRC progression. In the present study, we observed the expression change in protein and mRNA levels of ANXA1, ANXA4 and CA1 in large clinical samples with different clinical stages and differentiation degree, and the relationship between prognosis and these molecules was also analyzed, and our foundation will provide experimental evidence for early diagnosis and prognosis.[Method]The specimens of colorectal cancer were collected and the clinical database was established. Western blot were performed to determine the expression patterns of ANXA1, ANXA4 and CA1 in colorectal cancers with different clinical stages and different differentiation degrees. At the same time, we also performed real-time PCR to test the expression patterns of the same three moleculas at transcription level. We also make a survival analysis use Kaplan-Meier curve, and discriminant analysis use leave-one-out cross-validation analysis in order to find which element can affect the prognosis of CRC patients. [Result](1) For ANXA1, at the different clinical stages, the protein expression level was up-regulated in the average level. The up-rate for stage I to stage IV are 88.9%,22.22%,55.56%and 62.50%, respectively. There was significant difference between the stageâ… and its own normal control. (PI=0.037). The expression pattern was consistent with the previous results. The expression of ANXA1 in the poorly-differentiated adenocarcinoma and well-differentiated adenocarcinoma was significantly higher than that in the normal tissue and moderate differentiated adenocarcinoma (P>0.05). For ANXA4, compared with their own normal control, there was significant difference at theâ… andâ…£stage. According to the different degree of differentiation, there was high expression level in the well-differentiation degree and low expression level in the poorly-differentiation degree(P=0.047). For CA1, it had very low expression level in carcinoma tissue, especially at theâ…¢andâ…£stage(P<0.05), and it also gradually decreased from well-differentiation tissue to poorly-differentiation tissue, the expression level of CA1 between well-differentiated adenocarcinoma and poorly-differentiated adenocarcinoma had significant difference(P<0.05).(2) At the mRNA level, ANXA4 and CA1 had a very similarly expression mode with the protein level, but there are some difference with the ANXA1's expression mode at protein level.The expression level of ANXA4 was higher than normal tissue at the Stageâ… /â…¢/â…£(P<0.05), at Stageâ…¡, it had a lower expression level in the carcinoma, but the difference didn't have statistically significant(P>0.05). CA1's expression level was lower than normal tissue at every stage(P<0.05).(3) Kaplan-Meier survival analysis showed there was no significant relationship between ANXA1, ANXA4 and prognosis, p-value of ANXA1 was 0.532 and p-value of ANXA4 was 0.638. CA1 was extremely related to CRC prognosis, the log-rank test showed the p-value was 0.029.[Conclusion]1. ANXA1 had the highest expression level atâ… Stage, it suggested that ANXA1 can be a molecula which had changed at the early stage of cacinoma; The expression level of ANXA4 increased obviously at the IV stage, it maybe implied that when ANXA4 had a high expression level, it can promote the tumor cells metastasis. And we can deduce from the result that loss of expression of CA1 consistently accompanies progression to malignant transformation.2. ANXA1/ANXA4/CA1 all had the dynamic expression patterns at different clinical stages of CRC, and ANXA4/CA1 had the similarly expression patterns both at protein level and mRNA level. It can proofed the 2D-DIGE is a good and reliable method which used to screen the differential molaculas at protein level.3. CA1's expression level can predict the prognosis of CRC patients, but the expression of ANXA1 and ANXA4 can not do this. The discriminant function which set up on the basis of the expression level of ANXA1/ANXA4/CA1 can make a good discriminant of the over all suvival status and event free survival status, especially the EFS.