Expressions of resistance proteins P-gp, BCRP and LRP: A comparison between primary and metastatic breast carcinoma / 第二军医大学学报

ABSTRACT

Objective to investigate the differences n expressions of P-glycoprotein (P-gp), breast cancer drug resistance protein (BCRP) and pulmonary resistance protsnn (LRP) between psimary breast careinoma and metastatic lymph nodes. Methods The expressions of P-gp, BCRP and LRP in breast cancer tissues, including 126 primary carcinoma and 66 metastasis lymph nodes, were determined immunohistochemically on formalin-fixed, paraffin-embedded tumor sections. Results (1)The positive expression rates of P-gp, BCRP and LRP were 41. 27% (52/126), 38. 89% (49/126), and 65. 87% (83/126) in primary breast carcinoma, and were 59. 09% (39/66), 63. 64%(42/66),and 60. 61% (40/66) n metastatic lymph nodes, respctively. The posiiive rates of P-gp and BCRP in the metastatic lymph nodes were significantly higher than those in primary cancer iissue(P0. 05). (2) There was a poor consistency in P-gp and BCRP expressoon between the psimary and metastatic sites(P0. 05). (3) The co-expresion rate of two resistance proteins in primary breast carcinoma was 35. 71%(45/126), of three resistance proteins was 15. 08%(19/ 126), and of two or three resistance proteins was 50. 79% (64/126), being significantly higher than that of a single protein 33. 33% (42/126,P<0. 05). The co-expression rate of two resistance proteins in metastasis lymph nodes was 53. 03% (35/66), which was significantly higher than that of a single protein 27. 27% (18/66, P < 0. 05). The co-expression rate of three resistance proteins was 16. 67%(11/66), two or three resistance proteins was 69. 70%(46/66), which was significantly higher than that of a single protein (P<0. 01). Both the co-expresion levels of two resistance proteins and two or three resistance proteins in metastatic lymph nodes were significantly higher than those in primary cancer (P<0. 05). (4)Kaplan-Meier analyses revealed that patients with P-gp, BCRP and LRP expressed in the metastatic lymph nodes had a lower 5-year survival rate compared with patients whose primary breast cancer being positive for them. Conclusion The expression of P-gp and BCRP is different between the primary and metastatic breast cancer sites, and there is no signAcant difference in LRP expression. Coordination of multi-protein expression is a major feature of resistance. Metastasis lymph nodes may have a stronger resistance.