Expression levels and patterns of B-cell maturation antigen in newly diagnosed and relapsed multiple myeloma patients from Indian subcontinent.

BACKGROUND: Many novel therapies are being evaluated for the treatment of Multiple myeloma (MM). The cell-surface protein B-cell maturation antigen (BCMA, CD269) has recently emerged as a promising target for CAR-T cell and monoclonal-antibody therapies in MM. However, the knowledge of the BCMA expression-pattern in myeloma patients from the Indian subcontinent is still not available. We present an in-depth study of BCMA expression-pattern on abnormal plasma cells (aPC) in Indian MM patients. METHODS: We studied BM samples from 217 MM patients (211-new and 6-relapsed) with a median age of 56 years (range, 30-78 years & M:F-2.29) and 20 control samples. Expression levels/patterns of CD269 (clone-19f2) were evaluated in aPCs from MM patients and in normal PCs (nPC) from uninvolved staging bone marrow samples (controls) using multicolor flow cytometry (MFC). Expression-level of CD269 was determined as a ratio of mean fluorescent intensity (MFI-R) of CD269 in PCs to that of non-B-lymphocytes and expression-pattern (homogenous/heterogeneous) as coefficient-of-variation of immunofluorescence (CVIF). RESULTS: Median (range) percentage of CD269-positive abnormal-PCs in total PCs was 71.6% (0.49-99.29%). The MFI-R (median, range) of CD269 was significantly higher in aPCs (4.13, 1.12-26.88) than nPCs (3.33, 1.23-12.87), p < .0001. Median (range) MFI of CD269 at diagnosis and relapse were 2.39 (0.77-9.57) and 2.66 (2.15-3.23) respectively. CD269 levels were similar at diagnosis and relapse, p = .5529. CONCLUSIONS: We demonstrated that BCMA/CD269 is highly expressed in aPCs from a majority of MM patients, both at diagnosis and relapse. Thus, BCMA is a valuable target for therapy for Indian MM patients.

Expression of CD269 and CD317 in Multiple Myeloma and Its Clinical Significance / 现代检验医学杂志

Objective To study the expression of CD269 and CD317 antigens in bone marrow cells of patients with multiple myeloma (MM),analyze its correlation with the laboratory indexes reflecting the progression of MM and evaluate its value in clinical diagnosis and treatment.Methods 63 newly diagnosed MM patients were selected as the study group by a casecontrol study.The expression rate of CD269 and CD317 in bone marrow blood of 35 patients with iron deficiency anemia and other antigens in bone marrow blood of 63 patients with MM were detected by flow cytometry.The levels of serum hemoglo bin (Hb),serumβ2-MG(β2-MG) and lactatedehydrogenase (LDH) in patients with MM were dctectcd,and the levels of CD269 and CD317 were analyzed statistically.Results The positive rates of CD269 in the study group and control group were (86.6±2.35)％ vs (4.33±l.69)％,rcspectivcly (t =4.256,P＜0.05)).The positive rate of CD317 was (71.42+ 0.62)％ vs (8.32+ 3.89)％,the difference was statistically significant (t=3.102,P＜0.05).In other expression,the expression level of CD269 and CD317 in CD56 positive group was significantly higher than that of negative group (t=4.032,P＜0.05),while the expression of CD117 the level of positive group was significantly lower than that of the negative group (t 2.832,P＜0.05),CD19,CD20 expression was not statistically significant difference between the two groups (P＞ 0.05).The levels of CD269 and CD317 in patients with MM were positively correlated with the level of CD56 expression (r =0.392,P＜0.05),and negatively correlated with the level of CD117 expression (r=-0.210,P＜0.05).The levels of CD269 and CD317 in patients with MM were significantly lower than those in the negative group (t=3.012,P＜0.05) and the levels of serum LDH in the positive group were lower than those in the negative group (t=2.024,P＜0.05).There was a negative correlation between Hb content (r=-0.212,P＜0.05) and negatively correlated with serum β2-MG (r=-0.312,P＜0.05).Conclusion The high expression of CD269 and CD317 in bone marrow cells in MM patients is related to the increase of CD56 and decrease of CD117 in patients with MM.

Differential Expression of CD269 and CD317 Genes in Bone Marrow of Patients with Multiple Myeloma / 现代检验医学杂志

Objective To explore the differential expression of CD269 and CD317 in patients with multiple myeloma(MM). Methods Newly diagnosed samles from patients of MM(20 cases)and iron deficiency anemia(20 cases),40 cases in total (from 06/2015 to 08/2013,the Department of Hematology,Central Hospital of Zhuzhou City)were collected.Real-time quantitative PCR(RQ-PCR)tests were used to detect the relative expression of CD269 and CD317 in bone marrow sam-ples,and the results were statistically analyzed with clinical features.Results The relative expression levels of CD269 and CD317 in patients with multiple myeloma(4.418±4.568,4.327±2.876)were significantly higher than those in the control group(0.600±0.838,1.033±1.335),the difference was statistically significant(t=3.676,4.646,all P<0.05)respective-ly,while not related with the gender,age(P>0.05).There was no correlation between the expression of CD269 and CD317 (r=0.041,P=0.864),but positively correlated with the ratio of myeloma cells(r=0.495,P=0.026;r=0.533,P=0.016).Conclusion CD269 and CD317 were highly expressed in patients with multiple myeloma and may be involved in the pathogenesis of multiple myeloma.