Beihui Huang

Differentiation induction enhances bortezomib efficacy and overcomes drug resistance in multiple myeloma.

AIM It is of clinical importance to find methods to overcome bortezomib resistance. In the current study, we clarified the relationship between resistance to bortezomib and the differentiation status of myeloma cells, and explored the feasibility of induction of differentiation in overcoming bortezomib resistance in myeloma. METHODS Cell morphology, immunoglobulin light-chain protein secretion levels, and XBP-1 expression were used to evaluate the differentiation status of myeloma cells. Low dose 2-ME2 alone or in combination with ATRA was used to induce differentiation in myeloma cells. RESULTS The differentiation status of myeloma cells was related to myeloma sensitivity to bortezomib. After successful induction of differentiation, the myeloma cells were more sensitive to bortezomib with decreased growth and an increased rate of apoptosis. Induction of differentiation increased the proteasome workload in myeloma cells by increasing immunoglobulin secretion, while reducing proteasome capacity by decreasing proteasome activity. The imbalance between increased proteasome workload and decreased proteasome capacity is a possible mechanism by which induction of differentiation overcomes myeloma resistance to bortezomib. CONCLUSION The current study demonstrated, for the first time, that myeloma differentiation status is associated with myeloma sensitivity to bortezomib and that induction of differentiation can overcome myeloma resistance to bortezomib.

Hepatitis B virus reactivation in patients with multiple myeloma receiving bortezomib-containing regimens followed by autologous stem cell transplant.

Abstract To investigate hepatitis B virus (HBV) reactivation and survival in patients with multiple myeloma (MM) receiving bortezomib-containing regimens, we analyzed 139 patients with MM receiving bortezomib-containing regimens in our hospital. Twenty-seven/139 patients were hepatitis B surface antigen positive (HBsAg+) with nine having DNA levels > 500 IU/mL, including four > 1000 IU/mL. All but five HBsAg+ patients were treated with lamivudine or entecavir before chemotherapy until at least 6 months after chemotherapy or autologous stem cell transplant (ASCT). HBV reactivation occurred in six HBsAg+ patients and two HBsAg− patients, including six who received ASCT. Overall survival and progression-free survival of HBsAg− patients were significantly longer than for HBsAg+ patients (both p < 0.01). From these results, we confirmed that the incidence of HBV reactivation was notable in patients with MM receiving bortezomib-containing regimens, especially those who underwent ASCT. HBsAg+ patients with MM had a poorer prognosis than HBsAg− patients. Prophylactic treatment should be prescribed to all patients with HBsAg+ MM for a minimum duration of 12 months.

High prevalence of hepatitis B virus infection in multiple myeloma

Abstract The aim of the present study was to verify the potential association between multiple myeloma (MM) and hepatitis B/C virus (HBV/HCV) infection. This retrospective case–control trial included 299 patients with MM and 299 patients with acute leukemia (AL). Age and sex were matched between the two groups. The hepatitis B surface antigen (HBsAg) positivity rate was significantly higher in the MM group (19.4% vs. 12.0% in patients with AL; p = 0.014). The rate of HCV infection did not differ between the two groups. The incidence of cirrhosis was significantly higher in HBsAg+ patients (17.2% vs. 6.2% in HBsAg− patients; p = 0.011). The rate of hepatitis E virus (HEV) infection was also significantly higher in HBsAg+ patients (5.2% vs. 0.4% in HBsAg− patients; p = 0.025). Hepatic damage was much more common in HBsAg+ patients than in HBsAg− patients both prior to (22.4% vs. 8.7%; p = 0.006) and during chemotherapy for MM (67.2% vs. 28.6%; p < 0.001). ISS stage, HBsAg+, the use of bortezomib and thalidomide and autologous stem cell transplant were significant factors for overall survival in univariate analysis. In the Cox regression analysis, ISS stage (p = 0.027), HBsAg+ (p = 0.042) and the use of thalidomide (p = 0.001) showed a significant effect on the OS of these patients. The prevalence of HBV infection is higher in patients with MM than in subjects with other hematological malignancies such as AL. Hepatic injury is more common in patients with MM with HBV infection, particularly during chemotherapeutic treatment. HBsAg positivity may be a prognosis factor in patients with MM in HBV endemic areas.

Everolimus enhances the cytotoxicity of bendamustine in multiple myeloma cells through a network of pro-apoptotic and cell-cycle-progression regulatory proteins

Bendamustine is a bifunctional alkylating agent with some efficacy in the treatment of newly diagnosed and relapsed/refractory multiple myeloma (MM). Everolimus, an mammalian target of rapamycin (mTOR) inhibitor, is a additional promising chemotherapeutic agent that has efficacy in a variety of cancers. We investigated the individual and combinational cytotoxic effects of these drugs in MM cell lines (RPMI8226 and MM1.S) and primary MM cells. Our results demonstrated a synergistic effect of these drugs, which was effective for both p53-wild-type and p-53-deleted MM cells, but was minimal in mononuclear cells from a healthy donor. Combination treatment with the two agents inhibited proliferation and promoted cytotoxicity and apoptosis as assessed by Annexin-V/PI staining, caspase-3 degradation, and PARP cleavage. Cell death was associated with the up-regulation of the pro-apoptotic protein Bax and the down-regulation of the anti-apoptotic proteins Mcl-1 and survivin. The combination drug treatment also promoted a decrease in the levels of the downstream target proteins of the mTOR pathway, p70s6k, and 4EBP-1, as well as an increase in the level of phosphorylation of the tumor suppressor protein p53 in MM1.S cells. p21 was also down-regulated upon treatment with the two drugs, suggesting a mechanism of sensitization through the release of cell cycle arrest. Our results demonstrate a network of regulatory factors that may contribute to the synergistic cytotoxicity of everolimus and bendamustine, and provide a rationale for application for the combinatorial treatment of MM with alkylating agents and mTOR inhibitors in future clinical practice.

Successful treatment of renal light chain (AL) amyloidosis with bortezomib and dexamethasone (VD).

OBJECTIVE To assess the efficacy and tolerability of bortezomib with dexamethasone for patients with renal light chain (AL) amyloidosis. METHODS Twelve newly diagnosed patients with renal AL amyloidosis were treated with a combination of bortezomib (1.3mg/m(2)/d iv, d1, 4, 8, 11) and dexamethasone (20mg/d iv drip, d1-4). RESULTS Median follow-up time was 22.5 months (range, 2.1-53.6). Ten patients were evaluable. Five out of 10 (50%) patients achieved complete hematologic responses (CHR), and totally 8/10 (80%) achieved hematologic responses (HR). Median time to hematologic response was 1 month. All patients who received HR had no hematologic progression during follow-up period. Five patients (50%) had kidney responses and the other 5 patients (50%) were stable. Median time to kidney response was 3 months. No patients presented renal progression during follow-up. One patient achieved PR after 4 cycles of VD and then received autologous peripheral blood stem cell transplantation. Two out of 10 evaluable patients without hematologic response had died with median overall survival of 8.2 months. Eight of them who had HR were alive with median follow-up time of 28.5 months. Infection (6/12) and fatigue (5/12) were the most frequent side effects. Three patients developed herpes zoster and had to discontinue therapy. CONCLUSIONS VD produces rapid, deep and durable hematological responses and renal responses in the majority of patients with newly diagnosed renal AL. It is well tolerated. This treatment may be a good option as first-line treatment for renal AL amyloidosis patients.

Reduced response of IRE1α/Xbp-1 signaling pathway to bortezomib contributes to drug resistance in multiple myeloma cells.

Purpose Proteasome inhibition with bortezomib eliminates multiple myeloma (MM) cells by partly disrupting unfolded protein response (UPR). However, the development of drug resistance limits its utility and resistance mechanism remains controversial. We aimed to investigate the role of IRE1α/Xbp-1 mediated branch of the UPR in bortezomib resistance. Methods The expression level of Xbp-1s was measured in 4 MM cell lines and correlated with sensitivity to bortezomib. LP1 and MY5 cells with different Xbp-1s level were treated with bortezomib; then pivotal UPR regulators were compared by immunoblotting. RPMI 8226 cells were transfected with plasmid pEX4-Xbp-1s and exposed to bortezomib; then apoptosis was determined by immunoblotting and flow cytometry. Bortezomib-resistant myeloma cells JJN3.BR were developed and the effect on UPR signaling pathway was determined. Results By analyzing 4 MM cell lines, we found little correlation between Xbp-1s basic level and bortezomib sensitivity. Bortezomib induced endoplasmic reticulum stress-initiated apoptosis via inhibiting IRE1α/Xbp-1 pathway regardless of Xbp-1s basic level. Exogenous Xbp-1s reduced cellular sensitivity to bortezomib, suggesting the change of Xbp-1s expression, not its basic level, is a potential marker of response to bortezomib in MM cells. Furthermore, sustained activation of IRE1α/Xbp-1 signaling pathway in JJN3.BR cells was identified. Conclusions Our data indicate that reduced response of IRE1α/Xbp-1 signaling pathway to bortezomib may contribute to drug resistance in myeloma cells.

Prognostic value of lactate dehydrogenase in Chinese patients with newly diagnosed transplant eligible multiple myeloma

Beihui Huang , Jin Lu , Xiaotao Wang, Yang Xiao, Ying Zhao, Hongming Huang, Junru Liu, Meilan Chen, Jingli Gu, Shiwen Yuan, Dong Zheng, Yonghua Li, Xiaojun Huang and Juan Li Department of Hematology, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China; Department of Hematology, Peking University Institute of Hematology, Peking University People’s Hospital, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, Beijing, China; Department of Hematology, Guilin Medical College, Guilin, China; Department of Hematology, The General Hospital of Guangzhou Military Command of PLA, Guangzhou, China; Department of Hematology, The First People’s Hospital of Foshan, Foshan, China; Department of Hematology, Affiliated Hospital of Nantong University, Nantong, China

CD20-positive multiple myeloma: can conventional chemotherapy still be used to achieve ideal outcome for these patients?

In order to ascertain clinical characteristics and outcomes of CD20 + multiple myeloma (MM) patients, we retrospectively analyzed 331 newly diagnosed patients with multiple myeloma in our center. The clinical characteristics, cell morphology, immunophenotype, and cytogenetic were different between the CD20 + and CD20 − group. The median course of treatment to < nCR (near complete recovery) were 4.5 in the CD20+ group and 2 in the CD20 − group. Excluding the IgD type, overall survival (OS) and progression-free survival (PFS) in the CD20 + group were higher than that in the CD20 − group. There were no statistically significant differences in PFS and OS in CD20+ patients after treatment with conventional regimens, novel drugs ± transplant, nor statistical significance between those with the response < nCR and < nCR after treatment. In conclusion, CD20-positive myeloma cells are a cluster with heterogenous clinical characteristics, cell morphology, immunophenotype and cytogenetics. For these non-IgD CD20 + MM patients, conventional therapy might be a choice to achieve an ideal outcome.

Longitudinal Flow Cytometry Identified “Minimal Residual Disease” (MRD) Evolution Patterns for Predicting the Prognosis of Patients with Transplant-Eligible Multiple Myeloma

Many questions about minimal residual disease (MRD) still need to be answered for multiple myeloma (MM). Flow MRD was monitored in 104 consecutive patients with MM after induction and at the 3rd, 6th, 9th, 12th, 18th, and 24th months post-transplant. Four MRD evolution patterns were revealed: Pattern 1 patients had persistent MRD-negative status after post-induction with no progression; pattern 2 patients had MRD-positive status postinduction but became MRD negative within 24 months post-transplant; pattern 3 patients had MRD-negative status postinduction but became MRD positive within 24 months post-transplant; and pattern 4 patients had persistent MRD-positive status after postinduction. Patients with MRD evolution pattern 1 had a better time to progression than did patients with the other evolution patterns (not reached versus not reached, versus 15.4 ± 2.4 months, versus 16.9 ± 3.0 months; log-rank test, P = .003, P = .000, and P = .000, respectively). Patients with MRD pattern 1 had a significantly longer overall survival than did patients with pattern 3 (not reached versus 35.2 ± 18.6 months; log-rank test, P = .000) and pattern 4 (not reached versus 23.8 ± 15.0 months, log-rank test, P = .000) but had a similar overall survival as pattern 2 patients (not reached versus not reached; log-rank test, P = .229). For progressing patients with MRD evolution pattern 2 or 3, the median interval of a sustained MRD-negative status was only 17 months and the median time from MRD reappearance to disease progression was only 4.6 months. A more complete MRD evolution pattern was developed to predict the outcomes for patients with MM. The optimal time of MRD assessment should include postinduction and 3rd and 24th month post-transplant. Regular MRD assessments will help detect relapse early. A sustained negative MRD status should last for at least 24 months.

Application of PET/CT in treatment response evaluation and recurrence prediction in patients with newly-diagnosed multiple myeloma

Multiple myeloma (MM) causes osteolytic lesions which can be detected by 18F-fluorodeoxyglucose positron emission tomography/Computed tomography (18F-FDG PET/CT). We prospectively involve 96 Newly diagnosed MM to take PET/CT scan at scheduled treatment time (figure 1), and 18F-FDG uptake of lesion was measured by SUVmax and T/Mmax. All MM patients took bortezomib based chemotherapy as induction and received ASCT and maintenance. All clinical features were analyzed with the PET/CT image changes, and some relationships between treatment response and FDG uptakes changes were found: Osteolytic lesions of MM uptakes higher FDG than healthy volunteers, and this trend is more obvious in extramedullary lesions. Compared to X-ray, PET/CT was more sensitive both in discoering bone as well as extramedullary lesions. In newly diagnosed MM, several adverse clinical factors were related to high FDG uptakes of bone lesions. Bone lesion FDG uptakes of MM with P53 mutation or with hypodiploidy and complex karyotype were also higher than those without such changes. In treatment response, PET/CT showed higher sensitivity in detecting tumor residual disease than immunofixation electrophoresis. But in relapse prediction, it might show false positive disease recurrences and the imaging changes might be influenced by infections and hemoglobulin levels. Conclusion: PET/CT is sensitive in discovering meduallary and extrameduallary lesions of MM, and the 18F-FDG uptake of lesions are related with clinical indictors and biological features of plasma cells. In evaluating treatment response and survival, PET/CT showed its superiority. But in predicting relapse or refractory, it may show false positive results.