Objective: To study the expression and significance of RABEX-5 and RAB5 in human breast cancer.
Methods: In this study the expression of RABEX-5 and RAB5 mRNA and protein was detected by Immunohistochemical techniques, the reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot assay in 60 cases of breast cancer, 15 cases of breast fibroadenomas and 15 cases of normal breast tissue. The relationship of RABEX-5, RAB5 and the clinic pathological features was also analyzed.
Results: Expression of RABEX-5 and RAB5 in breast cancer was obviously higher than that in breast fibroadenomas and normal breast tissue (P < 0.05). RABEX-5 and RAB5 expression level in tumor diameter (T) >5 cm group of human breast cancer was obviously higher than that in T < or =2 cm and 2 < T < or =5 cm group (P < 0.05). RABEX-5 and RAB5 expression level in axillary lymph node positive group was obviously higher than that in negative group (P < 0.05). However, there were no significant differences of RABEX-5 and RAB5 levels between HER-2 (+) group and HER-2 (-) group (P > 0.05), ER (-) group and ER (+) group (P > 0.05), PR (-) group and PR (+) group (P> 0.05), and in histological grade I, II and III, there also were no significant differences of RABEX-5 and RAB5 levels. The expression of RABEX-5 is correlated with RAB5 in both mRNA and protein level.
Conclusion: RABEX-5 and RAB5 may be involved in the development of breast cancer metastasis.