The Expression Of C35 In Colorectal Cancer And Its Clinical Significance

ObjectivesColorectal cancer (CRC) is one of the most common malignant tumor in digestive system;around the world about 8 million new cases each year, accounting for all the malignant tumor 10%-15%. In China, the incidence of CRC has been increasing in recent years with the improvement of living condition and the change of dietetic habit. Early detection and treatment is critical for CRC, which is significantly associated with patients’prognosis. Cancers that are confined within the wall of the colon may be curable with surgery while tumor that has already spread widely are usually not curable, with chemotherapy focusing on improving quality of life and symptoms. Individualized treatment with targeted agents such as cetuximab has many advantages over traditional cytotoxic agents and will be the future trend for CRC treatment. In this sense, identification and characterization of cancer-specific biomarkers has enormous potential to facilitate detection and treatment of CRC.Methods65 cases of fresh cancer tissues and 55 cases of tumor-adjacent tissues were obtained via open surgery or endoscopic surgery from the Third Affiliated Hospital of Shandong Academy of Medical Sciences with informed consent from patients from June 2012 to June 2014 years. All the specimens were preserved in RNA-free Waiter, after stored in -80℃ ultra-low temperature refrigerator.1. Qualitative detection of C35 mRNA expression was performed using reverse transcription-PCR (RT-PCR).2. Quantitative detection of C35 mRNA expression between cancer tissues and tumor-adjacent tissues was performed using Real-time PCR.A total of 80 paraffin-embedded colorectal carcinoma (grade 1,2 and 3) and 10 normal tissues were selected from King Med Diagnostics from January 2013 to June 2014. All the patients were not undergoing chemotherapy and radiotherapy before radical surgery, the clinical data of patients were collected.1. The protein expression level of C35 were detected by immunohischemical staining in CRC tissues and normal tissues.2. Analysis of C35 expression with the clinicopathological parameters of CRC.Results1. Results demonstrated that 55 of 65 (84.6%) colorectal carcinoma tissues and 43 of 55 (78.2%) tumor-adjacent tissues were positive for C35 expression. On the other hand, all the normal colorectal tissues were negative for C35 expression. C35 mRNA level in cancer tissues is 5-to 10-fold higher than that in the adjacent tissues. There was a significant difference between the two groups (p< 0.05).2. C35 protein expressed mainly in cytoplasm, showing as brown granules. C35 protein expression was examined in 80 CRC tissues and 10 normal colorectal tissues using immunohistochemistry. Results showed that C35 expression was not found in normal colorectal tissues. On the other hand,58 of 80 CRC tissues (72.5%) showed varied degrees of C35 expression.3. No significant associations were found between C35 expression and other clinicopathological parameters such as gender, age, tumor location, tumor diameter, and tumor differentiation. C35 protein expression was associated with tumor serosal invasion, lymphnode metastasis, and advanced Dukes stage. on carcinoma.ConclusionsWe demonstrated in the present study that C35 has obvious expression advantage in CRC tissues compared to normal colorectal tissues or tumor adjacent non-cancerous tissues. Furthermore its expression is closely associated with invasive behavior of CRC. These results suggested the potential of utilizing C35 as a biomarker or therapeutic target for CRC management. A larger sample analysis on C35 expression, its biological functions in CRC progression, and drugs targeting this molecule should be further studied in the future.