Expression And Clinical Significance Of Ki-67 And P-glycoprotein(P-gp) In Human Chondrosarcoma

Objective: Chondrosarcoma is a malignant tumor of connective tissue,which is characterized by cartilage cells to differentiate trends and formation of cartilage matrix. Chondrosarcoma growth patterns varies, most tumors grow slowly, tend to local recurrence, the metastasis is un-usual happened or only when in the late,a small part has the rapid de-velopment and highly malignant form,and was accompanied by an early shift.Currently, the preferred method of treatment of chondrosarcoma is still complete surgical excision.However, the underlying molecular mechanisms and the development of research of chondrosarcoma tumor cells are not yet perfect.Proliferating cell nuclear antigen Ki-67 is a re-flection of cell division and proliferation activity marker in a variety of malignant tumors,especially breast cancer research in the popular bio-logical indicators, has been widely used clinically. Studies have shown that Ki-67 is effective in breast cancer prognostic indicators,high levels of Ki-67 protein expression is related to its adverse pathologic features and invasion behaviors.P-glycoprotein(P-gp) is a kind of encoded by multi-drug resistance gene(MDR), is highly expressed in many human malignant tumors,such as breast cancer, lung cancer, colorectal cancer and so on. In this experiment, we use immunohistochemical methods to detect human chondrosarcoma in the expression of Ki-67 and P-gp pro-tein,and its clinical significance and relationship to provide a theoretical basis for the clinical diagnosis of chondrosarcoma and rationalization of treatment.Methods: 50 cases of resected chondrosarcoma specimens have been collected from January 2007 to January 2013 in the Third Hospital of Hebei Medical University, including 17 cases of local recurrence or metastasis,33 cases not.All cases were diagnosed by pathological and imaging data,and were not underwent radiotherapy and chemotherapy before surgery. Immunohistochemistry was used to detect the expression of P-gp and Ki-67 of 50 cases of chondrosarcoma tissue, 20 cases of osteochondroma tissue to analyzed the relationship between the test re-sults and chondrosarcoma clinicopathological and biological behavior.Results:1 Expression of Ki-67 protein in chondrosarcoma and osteochondroma tissue: Ki-67-positive stain rate was 15%(3/20) in osteochondroma tissue and 54%(27/50) in chondrosarcoma tissue. The staining intensity and staining rate were compared, the differences were statistically significant(P <0.05).2 Expression of P-gp in chondrosarcoma and osteochondroma tissue: P-gp-positive stain rate was 5%(1/20) in osteochondroma tis-sue and 42%(21/50) in chondrosarcoma tissue. The staining intensity and staining rate were compared, the differences were statistically sig-nificant(P <0.05).3 Relationship between Ki-67 protein and P-gp expression in chondrosarcoma tissue: In the 50 cases of chondrosarcoma cells, Ki-67 protein and P-gp were both positive in 17 cases, while 19 cases were negative, there was no significant difference between the two groups(P <0.05). Spearman rank correlation was used to analyze the expression intensity between Ki-67 protein and P-gp,they were significantly posi-tively correlated.4 Ki-67 protein expression in relation to the clinicopathological characteristics in chondrosarcoma : Ki-67-positive stain rate was 34.8%(8/23) in gradeⅠgroup, 68.8%(11/16)in grade Ⅱgroup and 72.7%(8/11) in grade Ⅲgroup. Positive stain rate and intensity were compared in gradeⅠ,Ⅱand groupsⅢ, the differences were statistically significant(P<0.05). By pairwise comparisons between the groups,Ki-67-positive stain rate was higher in grade group than that Ⅲin the other two groups(P <0.05). There were significant differences of Ki-67-positive stain rate of chondrosarcoma tissue in gradeⅠ,Ⅱand Ⅲgroups(P <0.05).In addition, there were no relationship of expression of Ki-67 protein with the patient’s age, sex and tumor site, but with tu-mor size and recurrence or distant metastasis.5 P-gp expression in relation to the clinicopathological character-istics in chondrosarcoma:P-gp-positive stain rate was 21.7%(5/23) in grade Ⅰ group,43.8%(7/16) in grade Ⅱ group and 81.8%(9/11) in grade group. Positive Ⅲ stain rate and intensity were compared in grade Ⅰ,Ⅱ and Ⅲgroups, the differences were statistically significant(P <0.05). By pairwise comparisons between the groups,P-gp-positive stain rate was higher in grade Ⅲgroup than that in the other two groups(P <0.05).There were significant differences of P-gp-positive stain rate of chondrosarcoma tissue in gradeⅠ,Ⅱand Ⅲgroups(P<0.05).In addi-tion,there were no relationship of expression of P-gp protein with the pa-tient’s age,sex and tumor site,but with tumor recurrence or distant me-tastasis.Conclusion:1 The expression of Ki-67 and P-gp in chondrosarcoma tissue were both significantly higher than osteochondroma tissue. Ki-67 and P-gp were related to the biological behavior of chondrosarcoma.2 There was a significantly correlation between the expression of Ki-67 and P-gp in chondrosarcoma and the more active,the greater pos-sibility of drug resistance.3 Unite application of detecting Ki-67 and P-gp was regarded as an important clinicopathological index on judging the size of the tumor, the grade of the tumor, the malignancy of the tumor,and the prognosis of chondrosarcoma.