Clinical analysis of expression of CD47 in patients with multiple myeloma

Abstract

Objective To investigate the expression of CD47 in multiple myeloma (MM) and its clinical significance. Methods From September 2016 to May 2018, all of 25 cases of MM patients who were diagnosed and treated in Hongqi Hospital Affiliated to Mudanjiang Medical University were selected as research subjects, and enrolled in study group. In study group, there were 15 males and 10 females with the age of (58.5±4.2) years. Twelve MM patients were treated with CTD (cyclophosphamide+ thalidomide+ dexamethasone) regimen and the rest 13 cases with VAD (vincristine+ pirarubicin+ dexamethasone) regimen. Six cases of individuals who received physical examination in the same period and the same hospital were included in control group. In control group, there were 3 males and 3 females with the age of (56.3±4.1) years. CD47 expression levels of mononuclear cells in bone marrow from MM patients and peripheral blood from healthy individuals were detected by flow cytometry. Relationships between CD47 expression in MM patients and complete remission (CR), recurrence in study group were analyzed. The positive expression rate of CD47 of subjects in two groups, and CR rates of MM patients with different treatment regimens and CD47 expressions in study group were compared by Fisher′s exact probability method. The procedure of this study is accordance with the requirement of the revised World Medical Association Declaration of Helsinki in 2013. Informed consent was obtained from all participants. Results ① CD47 positive expression rate of MM patients in study group was 40.0% (10/25), and was significantly higher than that of 0(0/6) in control group, and the difference was statistically significant (P=0.018). ② In study group, CR rate of MM patients with positive CD47 expression was 20.0% (2/10), and was significantly lower than that of 73.3% (11/15) in patients with negative CD47 expression, and the difference was statistically significant (P=0.013). CR rate of MM patients receiving CTD regimen with positive CD47 expression was 16.7% (1/6), and was significantly lower than that of 83.3% (5/6) in pactients with negative CD47 expression, and the difference was statistically significant (P=0.040). CR rate of MM patients receiving VAD regimen with positive CD47 expression was 16.7% (1/6), and was significantly lower than that of 85.7%(6/7) in patients with negative CD47 expression, and the difference was also statistically significant (P=0.029). ③ There was no statistically significant difference in CR rate between patients with positive CD47 expression who were treated with VAD and these who were treated with CTD regimen (P=0.773). And there was no statistically significant difference in CR rate between patients with negative CD47 expression who were treated with VAD and these who were treated with CTD regimen (P=0.731). ④ All 2 MM patients with positive CD47 expression who obtained CR, and 2 of 11 MM patients with negative CD47 expression had relapsed. Conclusions The expression rate of CD47 on bone marrow mononuclear cells in MM patients was significantly higher and was related to curative effect and prognosis of MM patients. CD47 may be used as a potential auxiliary evaluation indicator for efficacy and prognosis in MM. This conclusion is limited to the clinical analysis of a small sample, and it requires large sample, multi-center, randomized controlled trials for further study and verification. Key words: Multiple myeloma; Antigens, CD47; Phagocytosis; Treatment outcome; Prognosis