Expression And Clinical Significance Of Sperm-associated Antigen9in Patients With Cervical Cancer And Cervical Intraepithelial Neoplasia

BackgroundCervical cancer is the third most commonly diagnosed cancer and the fourth leading cause of cancer death in females worldwide. The occurrence of cervical carcinoma is a multi-stage and multi-step progress,which could take10years from precancerous lesion. Therefore, cervical cancer is a preventable and curable disease. Due to the popularization of screening, the worldwide morbidity and mortality rates of cervical cancer have declined significantly over the past several decades. But there is still possibility of misdiagnosis because of the low sensitivity and specificity of ThinPrep cytologic test, and some traumatic examinations, such as colposcopy and cervical biopsy are hard to be accepted by patients. In addition, the monitoring of preoperative and prognosis in cervical lesion is not perfect. Therefore, looking for novel tumor biomarkers for early screening, clinical diagnosis and postoperative testing of cervical lesions, is particularly important.ObjectiveTo investigated the expression of SPAG9in cervical intraepithelial neoplasia and cervical carcinoma to assess its potential value as a novel biomarker in human cervical lesions.Methods1. Subjects:Cervical lesions and normal tissues were surgically obtained from patients undergoing surgery for cervical carcinoma and cervical intraepithelial neoplasia.40cases of cervical carcinoma tissues,35cases of CIN paraffin specimens and7cases of CIN fresh samples were selected.And20cases with normal cervical tissues were recruited into the control group.We also collected serum samples from40women with cervical carcinoma,40with CIN,20women with gynecologic benign diseases,10healthy women,and20postoperatives.2. Methods:(1)Immunohistochemistry(IHC) was used to clarify loealization of SPAG9in tissues.To detect the expression of SPAG9protein in cervical carcinoma, cervical intraepithelial neoplasia and normal cervical tissues.(2)Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of SPAG9mRNA in cervical carcinoma, cervical intraepithelial neoplasia and normal cervical tissues, using semi-quantitative analysis.(3)Western Blot was used to detect the expression of SPAG9protein in cervical carcinoma, cervical intraepithelial neoplasia and normal cervical tissues, and using semi-quantitative analysis.(4)SPAG9concentration in serum samples from10healthy women,20women with gynecologic benign diseases,40women with cervical intraepithelial neoplasia,40women with cervical carcinoma,and20postoperatives was detected by enzyme-linked immunosorbent assay(ELISA).Results1. Immunohistochemistry revealed the SPAG9expression was predominantly in the cytoplasm and cytomembrane but not in mesenchyme. The SPAG9expression in cervical carcinoma was significantly higher than that in cervical intraepithelial neoplasia, which similarly was,higher than that in control group(P<0.05).Further, association of SPAG9was examined with the various known risk factors of cervical cancer patients such as tumor grade, nodal status, and clinical stages. However, no statistically significant difference were observed in SPAG9expression.2. RT-PCR results showed SPAG9mRNA was observed in tumors but not in normal cervical tissues.Semi-quantitative analysis of SPAG9mRNA showed that the cervical carcinoma group had a mean±SEM SPAG9of0.815±0.553versus a mean±SEM of0.008±0.001in the control group(P<0.05).3. The trend of SPAG9protein expression in cervical cancer and normal cervical tissues, which were detected by Western Blot,agreed with immunohistochemistry and RT-PCR.Semi-quantitative analysis of SPAG9showed that the cervical carcinoma group had a mean±SEM SPAG9of0.929±0.908versus a mean±SEM of0.044±0.032in the control group, and difference between the two groups was statistically significant (P<0.05).4. Sperm-associated antigen9serum concentrations from the20women with gynecologic benign diseases and10healthy women had a mean±SEM of3.3561±0.7426ng/ml and3.2343±1.0579ng/ml respectively.SPAG9values from the their distributions were not statistically significantly different. In contrast,serum from40patients with cervical carcinoma had a mean±SEM of15.1404±10.3839ng/ml, and40patients with CIN had a mean±SEM of6.7015±3.3101ng/ml,these values were statistically significantly higher than those in the healthy group and the benign Group. Importantly,we observed a decrease in SPAG9levels in the20postoperatives without relapsing,whose serum concentration had a mean±SEM of3.6107±1.5069.Conclusions1.The SPAG9protein and mRNA expression in cervical carcinoma is significantly higher than that in cervical intraepithelial neoplasia, which similarly is higher than that in control group.2. SPAG9expression in serum of cervical cancer patients is higher than that in the CIN group, which is also higher than that of benign tumor and healthy women. There is a decrease in SPAG9levels in the20postoperatives without relapsing.3. SPAG9can be used as a new biomarker in early diagnosing and post-operational recurrence monitoring of cervical cancer and cervical intraepithelial neoplasia.