Expression And Function Of4-1BBL Molecular In Multiple Myeloma Patients；

Part1Expression and Function of4-1BBL Molecular in Multiple Myeloma Patients[Objective](1) To determine4-1BBL expression on primary patient Multiple Myeloma (MM) cells and human MM cell lines;(2) To explore the biological effect of4-1BBL reverse signaling on human MM cell line U266and its underlying mechanism.[Methods](1) The expression of4-1BBL on MM cells was detected by immunofluorescence staining and flowcytometric assay;(2) Triggered by anti-4-1BBL mAb (1F1), the proliferation of U266cell was measured by cell counting and MTT assay;(3) The change of cell cycle was analyzed by propidium iodide (PI) staining;(4) Intracellular cytokine staining and flowcytometry were performed to evaluate the IL-6production of U266cells;(5) To observe whether IL-6participated in the proliferation of U266cells triggered by4-1BBL reverse signaling, neutralizing anti-IL-6mAb was added to the culture medium to block the biology activity of IL-6;(6) MTT assay was performed to observe whether Bortizomib inhibited U266cells proliferation stimulated by mAb1F1.[Results](1)4-1BBL was highly expressed on patients MM cells in all20investigated cases as well as on MM cell lines (U266、OPM-2、MY-5、KMS-11、LP-1);(2) Both cell counting and MTT assay showed that mAb1F1promoted U266cells proliferation remarkably;(3) PI measurement showed a decrease in the number of cells in the G1phase and an increase in the S phase, indicating that1F1promotes the transition of U266cells from G1phase to S phase;(4) Intracellular cytokine staining demonstrated1F1increased the IL-6production of U266cells;(5) Neutralizing anti-IL-6mAb inhibited U266cells proliferation stimulated by mAb1F1;(6)1F1was unable to promote U266cells proliferation in the presence of Bortizomib.[Conclusions]4-1BBL is constitutively expressed on patients MM cells as well as MM cell lines;4-1BBL reverse signaling can promote the proliferation of U266cell through increasing the production of IL-6; Bortizomib can inhibit U266cells proliferation stimulated by1F1; and4-1BB/4-1BBL molecules may be valuable targets for the immunotherapy of multiple myeloma. Part2Therapeutic Effect of Autologous Hematopoietic Stem Cell Transplantation on27Patients with Multiple Myeloma[Objective]To evaluate the impact of autologous hematopoietic stem cell (ASCT) on the response as well as outcome with multiple myeloma (MM) patients and discuss factors influencing the prognosis.[Methods]Retrospective analysis was performed in27patients with MM treated with ASCT in our hospital from May2004to August2011. After comparing with28patients who achieved very good partial response (VGPR) or better outcome and not received ASCT, the impact on the depth of response, progression-free survival (PFS) and overall survival (OS) time as well as related prognosis factors of ASCT were analyzed.[Results]All patients were successfully underwent hematopoietic reconstruction without transplantation-related mortality. The complete remission (CR) rate of ASCT group increased from25.9%(7/27) before ASCT to70.4%(19/27) after ASCT (P<0.01). The progression-free estimated rate of survival for four years was (64.9±11.1)%(median not reached) in the ASCT group and (26.9±11.7)%(median20months) in the non-ASCT group (P<0.05). The probability of overall survival for five years was (52.2±15.7)%(median not reached) in the ASCT group and (33.1±24.2)%(median60months) in the non-ASCT group (P>0.05). Univariate analysis in ASCT group demonstrated that maintenance/consolidation therapy was associated with PFS (P=0.01) and OS (P<0.01); Patients who received induction therapy containing Boretizomib and early ASCT maintenance therapy all survival without disease progression till finish follow-up (P=0.01).[Conclusions]ASCT can further increase the CR rate, prolong the PFS and probably OS. The incorporation of these novel agents into induction, consolidation and maintenance phases has optimized the anti-myeloma activity of ASCT and maybe important for improvement of long-term outcome.