New drugs for treatment of multiple myeloma

Proteasome inhibitor bortezomib enhances the effect of standard chemotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive cancer showing a very poor prognosis because of metastasis formation at an early stage and acquisition of chemoresistance. One key driver of chemoresistance is the transcription factor Forkhead box protein M1 (FOXM1) that regulates cell cycle proliferation, maintenance of genomic stability, DNA damage response, and cell differentiation in numerous tumor entities. In this study we investigated the role of FOXM1 in SCLC progression and analyzed the effect of FOXM1 inhibition using two proteasome inhibitors, bortezomib and siomycin A. FOXM1 was strongly expressed in patient-derived SCLC samples (n=123) and its nuclear localization was associated with the proliferation marker Ki-67. Both proteasome inhibitors successfully inhibited FOXM1 expression leading to a significantly reduced proliferation and a decreased mitotic rate along with cell cycle arrest and apoptosis induction. These effects were further enhanced by addition of bortezomib to standard chemotherapy. Treatment of mice bearing chemoresistant SCLC xenografts with bortezomib reduced the mean bioluminescence signal of tumors by 54%. Similarly, treatment with cisplatin as a standard chemotherapy reduced the mean bioluminescence signal of tumors by 58%. However, in combination with standard chemotherapy bortezomib further reduced the mean bioluminescence signal by 93% (p=0.0258). In conclusion, we demonstrate the effect of bortezomib in inhibiting FOXM1 expression and thus in sensitizing resistant SCLC cells to standard chemotherapy. Thus, addition of bortezomib to standard chemotherapy might potently improve SCLC therapy, particularly in an extensive cancer stage.

Clinical impact of immunophenotypic remission after allogeneic hematopoietic cell transplantation in multiple myeloma

Immunophenotypic remission (IR) is a strong prognostic factor in myeloma patients. The combination of IR and conventional CR was retrospectively evaluated in 66 patients after allografting. IR was defined as the absence of monoclonal plasma cells in BM aspirates by multiparameter flow cytometry. Conditioning was non-myeloablative in 55 patients; reduced-intensity in 10 and myeloablative in 1 patient. The allograft was given upfront in 35/66 (53%) patients. After a median follow-up of 7.1 years, 24 patients achieved both CR and IR (CR/IR group), 21 achieved IR but not CR with persistence of a urine/serum M-component (no CR/IR group) and 21 did not achieve either CR or IR (no CR/no IR group). Median OS and EFS were 'not reached' and 59 months in the CR/IR group; 64 and 16 months in the no CR/IR; and 36 and 6 months in the no CR/no IR, respectively (P<0.001). Cumulative incidence of extramedullary disease was 4.4% in the CR/IR, 38.1% in the no CR/IR and 14.3% in the no CR/no IR groups, respectively, at 4 years (P<0.001). IR was a valid tool to monitor residual disease after allografting, and allowed definition of a cohort of patients at higher incidence of extramedullary relapse.

The combination of arsenic and cryptotanshinone induces apoptosis through induction of endoplasmic reticulum stress-reactive oxygen species in breast cancer cells

Arsenic trioxide has been successfully used for the treatment of patients with acute promyelocytic leukemia (APL) worldwide. Recently, it has also been further developed to treat solid tumors in clinical trials. However, the therapeutic effects on malignant tumors appeared to be unsatisfactory, as these cells exhibited resistance towards arsenic. In this study, we explored new therapeutic strategies for treatment of human breast cancer MCF-7 cells based on arsenic metabolites. The MCF-7 cells were exposed to three arsenic species, namely, inorganic arsenite (iAs(III)) and its intermediate metabolites monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)) either alone or in combination with cryptotanshinone (CPT) to establish their anticancer effects against MCF-7 cells. Surprisingly, MCF-7 cells were shown to be resistant to both iAs(III) and CPT when used alone; however, they were shown to be relatively sensitive to treatment when exposed to MMA(III) and DMA(III) alone. Conversely, the combination of MMA(III) with CPT showed significantly enhanced anticancer effects on MCF-7 cells at low doses, but no appreciable effect was observed upon exposure to the other two arsenic species with CPT. In addition, remarkable redistribution of pro-apoptosis related proteins Bax and Bak was observed in the mitochondria, together with activation of poly(ADP-ribose) polymerase (PARP) and caspase-9 after exposure to the combination of MMA(III) with CPT. Furthermore, we clearly found that induction of apoptosis in MCF-7 cells was predominantly triggered by endoplasmic reticulum (ER) stress after exposure to the combination of MMA(III) with CPT.

Interleukin-6 and JAK2/STAT3 signaling mediate the reversion of dexamethasone resistance after dexamethasone withdrawal in 7TD1 multiple myeloma cells

We previously reported the establishment and characteristics of a DXM-resistant cell line (7TD1-DXM) generated from the IL6-dependent mouse B cell hybridoma, 7TD1 cell line. After withdrawing DXM from 7TD1-DXM cells over 90 days, DXM significantly inhibited the cell growth and induced apoptosis in the cells (7TD1-WD) compared with 7TD1-DXM cells. Additionally, IL-6 reversed while IL-6 antibody and AG490 enhanced the effects of growth inhibition and apoptosis induced by DXM in 7TD1-WD cells. Our study demonstrates that 7TD1-DXM cells become resensitized to DXM after DXM withdrawal, and IL-6 and JAK2/STAT3 pathways may regulate the phenomenon.

Bortezomib and heart failure: case-report and review of the French Pharmacovigilance database

Bortezomib is a proteasome inhibitor commonly indicated for the treatment of multiple myeloma and non Hodgkin lymphoma. Cardiac adverse drug reactions of this drug are not clearly established. We report case where direct involvement of bortezomib in the occurrence of heart failure is strongly suspected and 22 other cases spontaneously reported to the French Pharmacovigilance System. This report should increase cardiologist awareness about the risk of heart failure related to this drug. Moreover, these cases underline the need for a systematic cardiac screening in patients exposed to bortezomib.

Metabolism of thalidomide by human liver microsome cytochrome CYP2C19 is required for its antimyeloma and antiangiogenic activities in vitro

In this study, we used a system of human liver microsomes to investigate the antimyeloma and antiangiogenic activities of thalidomide. Myeloma cells and human umbilical vein endothelial cells (HUVECs) were treated with thalidomide alone or thalidomide incubated with human liver microsomal protein. We found that thalidomide alone had no direct effect on several multiple myeloma cell lines (U266, NCI-H929, RPMI 8226, LP-1, CZ-1) or on HUVECs in vitro. However, when incubated with human liver microsomal protein, thalidomide (100 µg/ml) caused a decrease of 34.9-46.7% in cell viability in myeloma cells and 12% in HUVECs. Cell cycle analysis and apoptosis detection indicated that the decreases in cell viability were correlated with the induction of apoptosis. Thalidomide incubated with microsomal protein also influenced HUVEC migration and tube formation. These effects were partially reversed by omeprazole (10 µmol/l), a potent inhibitor of CYP2C19, suggesting that CYP2C19 is required for thalidomide to exhibit its antimyeloma and antiangiogenic activities.

Long-term follow-up of a comparison of nonmyeloablative allografting with autografting for newly diagnosed myeloma

Before the introduction of new drugs, we designed a trial where treatment of newly diagnosed myeloma patients was based on the presence or absence of HLA-identical siblings. First-line treatments included a cytoreductive autograft followed by a nonmyeloablative allograft or a second melphalan-based autograft. Here, we report long-term clinical outcomes and discuss them in the light of the recent remarkable advancements in the treatment of myeloma. After a median follow-up of 7 years, median overall survival (OS) was not reached (P = .001) and event-free survival (EFS) was 2.8 years (P = .005) for 80 patients with HLA-identical siblings and 4.25 and 2.4 years for 82 without, respectively. Median OS was not reached (P = .02) and EFS was 39 months (P = .02) in the 58 patients who received a nonmyeloablative allograft whereas OS was 5.3 years and EFS 33 months in the 46 who received 2 high-dose melphalan autografts. Among patients who reached complete remission in these 2 cohorts, 53% and 19% are in continuous complete remission. Among relapsed patients rescued with "new drugs," median OS from the start of salvage therapy was not reached and was 1.7 (P = .01) years, respectively. Allografting conferred a long-term survival and disease-free advantage over standard autografting in this comparative study.

Lenalidomide in multiple myeloma: an evidence-based review of its role in therapy

INTRODUCTION

Multiple myeloma (MM) is a relatively common and incurable hematological malignancy. Currently, there is no single standard therapy, with choice of treatment dependent on individual patient factors. Lenalidomide is an immunomodulatory drug with potent antitumor, antiangiogenic, immunomodulatory, and proapoptotic activity in MM.

AIMS

To evaluate the evidence for the use of lenalidomide in its current indication in relapsed or refractory MM, and additionally its investigational use for the treatment of newly diagnosed MM.

EVIDENCE REVIEW

In patients with relapsed and refractory MM, adding lenalidomide to high-dose dexamethasone significantly improves response rates and time-to-progression, relative to high-dose dexamethasone alone. This translates into a significant extension of overall survival (with a median extension of 9.1 months in a pivotal phase III study). Outcome is independent of patient age, number of previous therapies, type of previous therapy (including thalidomide or autologous stem cell transplantation), renal impairment, and beta(2)-microglobulin level. Evidence suggests that combining lenalidomide with low-dose dexamethasone improves outcomes in patients with newly diagnosed disease and is superior to lenalidomide combined with high-dose dexamethasone. Myelosuppression is the predominant toxicity observed, although some studies have shown high incidences of venous thromboembolism in the absence of prophylactic antithrombotic anticoagulation therapy. There is currently only limited evidence regarding the health economics of lenalidomide. ROLE IN THERAPY: The encouraging results obtained with lenalidomide alone and in combination with dexamethasone in patients with relapsed or refractory MM have led to its adoption as a recommended therapy in patients who have received at least one prior treatment. Emerging evidence supports the ongoing investigation of lenalidomide in combination with low-dose dexamethasone, and in other combinations including bortezomib, for use both in relapsed, refractory, and newly diagnosed MM.

Multiple myeloma

Advances in the imaging and treatment of multiple myeloma have occurred over the past decade. This article summarises the current status and highlights how an understanding of both is necessary for optimum management.

Somatostatin and opioid receptors do not regulate proliferation or apoptosis of the human multiple myeloma U266 cells

BACKGROUND

opioid and somatostatin receptors (SSTRs) that can assemble as heterodimer were individually reported to modulate malignant cell proliferation and to favour apoptosis.

MATERIALS AND METHODS

SSTRs and opioid receptors expression were examined by RT-PCR, western-blot and binding assays, cell proliferation was studied by XTT assay and propidium iodide (PI) staining and apoptosis by annexin V-PI labelling.

RESULTS

almost all human malignant haematological cell lines studied here expressed the five SSTRs. Further experiments were conducted on the human U266 multiple myeloma cells, which express also micro-opioid receptors (MOP-R). XTT assays and cell cycle studies provide no evidence for a significant effect upon opioid or somatostatin receptors stimulation. Furthermore, neither direct effect nor potentiation of the Fas-receptor pathway was detected on apoptosis after these treatments.

CONCLUSION

these data suggest that SSTRs or opioid receptors expression is not a guaranty for an anti-tumoral action in U266 cell line.

Apoptotic resistance exhibited by dexamethasone-resistant murine 7TD1 cells is controlled independently of interleukin-6 triggered signaling

Interleukin-6 (IL6)-mediated signaling is known to play a role in pathogenesis and resistance in several cancers like multiple myeloma (MM). In this report we used the IL6-dependent 7TD1 murine B-cell hybridoma as an in vitro model to study the interactions between IL6-signaling pathways and the development of dexamethasone resistance. Though in initial stages, 7TD1 cells grew IL6-dependent and were sensitive to dexamethasone-induced apoptosis, chronic exposure to dexamethasone led to a dexamethasone-resistant phenotype (7TD1-Dxm) that grew independent of exogenous IL6. While IL6-mediated JAK/STAT3 and PI3K/AKT signaling was important for proliferation of both cell lines, as shown in proliferation assays using the respective pathway inhibitors, AG490 and LY294002, the resistant cells were insensitive to induction of apoptosis using the same. STAT3 was constitutively phosphorylated in resistant cells and inhibition of its dimerization induced apoptosis but did not alter their insensitivity to dexamethasone. Our results suggest a role of entities downstream of IL6-mediated JAK/STAT3 signaling in development of dexamethasone resistance by 7TD1-Dxm cells.

[Bortezomib in relapsed or refractory multiple myeloma: results in a cohort of 39 patients]

INTRODUCTION

Bortezomib has presently become a significant rescue treatment in multiple myeloma (MM) due to its observed effectiveness and safety in multicenter trials. We have aimed to verify both aspects in a setting of non-selected patients.

PATIENTS AND METHODS

This is an observational, prospective study of the cohort of relapsed or refractory MM patients treated with bortezomib in our Department. The variables analyzed were response, its duration, time to the treatment failure (TTF), overall survival (OS), response related conditions and toxicity. Statistical methods used were Fisher's exact test, log rank-test and Kaplan-Meier survival tables.

RESULTS

A total of 39 patients, 25 relapsed and 14 refractory to chemotherapy, started the treatment. The mean number of previous treatment was 2.3 and they received an average of 5.8 cycles of bortezomib. Complete response was achieved in 14 patients (36%), partial response in 12 (31%) and minor or no response in 13 ones (33%). Median duration of response was 8 months, median TTF was 10 months and median OS, from the onset of bortezomib was 16.5 months, with a median observation of live patients of 12.5 months. The response was more frequent in males (p = 0.019) and in patients with one previous treatment (p = 0.15). There were no significant differences regarding to TTF when we considered the cause of treatment (relapse or no response to chemotherapy) nor in the number of previous treatment regimes. The most frequent adverse events were reversible thrombocytopenia (31%), polyneuropathy (28%) and asthenia-anorexia (23%).

CONCLUSIONS

In our cohort of non-selected, relapsed or refractory MM patients, the observations found in the multicenter randomized trials results regarding response rate and duration, TTF OS and safety of bortezomib therapy were verified.

Multiple myeloma and treatment-related thromboembolism: oncology nurses' role in prevention, assessment, and diagnosis

Immunomodulating agents such as thalidomide and its newly emerged derivative, lenalidomide, are becoming increasingly popular in the treatment of multiple myeloma because of their ability to combat drug resistance. Clinical trials suggest that thalidomide and lenalidomide are effective in all stages of multiple myeloma treatment-new diagnoses, stem cell transplantations, maintenance therapy, and relapsed or refractory disease. The drugs are most efficacious when combined with additional chemotherapeutic agents and/or corticosteroids. However, deep vein thrombosis and other thromboembolic events are associated with the treatment regimens. Oncology nurses must understand the pharmacologic properties of the drugs and the potentially life-threatening complications associated with them. To provide the highest standard of care, oncology nurses must play a vital role in the prevention, diagnosis, and management of thromboembolic events through awareness of the clinical problem, assessment tools, and thromboembolic prophylactic regimens.

Cholesterol levels in patients with multiple myeloma

Hypocholesterolemia is seen in solid tumors and some hematological malignancies. We assessed cholesterol levels and the relationship between these levels and types and stages of multiple myeloma (MM) in the patients with MM. One-hundred two patients (60 male and 42 female) of mean age 59 +/- 11 years with MM were enrolled to this study. While 71.6% of the patients were Ig G type, 80.4% of the patients were at stage III. In the control group, there were 71 healthy persons (42 male and 29 female) of mean age 58 +/- 8 years. The levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in the patients with MM were significantly lower than the controls (p < 0.001). There was no difference for the levels of very-low-density lipoprotein cholesterol and triglyceride between the two groups (p > 0.05). Lipid parameters were not different between Ig types (p > 0.05). The levels of TC and LDL-C in the patients with stage I were higher than those of stages II and III (p < 0.001 and p < 0.005, respectively). The levels of TC and LDL-C in the controls were not higher than the patients with stage I (p > 0.05). HDL-C levels in the patients with stage III were lower than controls (p < 0.001). Hypocholesterolemia are seen in the patients with MM. Hypocholesterolemia may be due to increased LDL clearance and utilization of cholesterol by myeloma cells.

Unrelated donor haematopoietic cell transplantation after non-myeloablative conditioning for patients with high-risk multiple myeloma

BACKGROUND

Allografting induces long-term molecular remissions and possibly cure in myeloma patients. The development of non-myeloablative conditionings has reduced the transplant-related mortality (TRM) associated with myeloablation and extended the eligible age for transplantation. Moreover, high response rates are reported especially when allografting is preceded by cytoreductive high-dose chemotherapy. We investigated the feasibility of unrelated donor non-myeloablative transplantation as either part of the initial treatment plan or as salvage treatment in heavily pretreated patients.

METHODS

Twenty-two patients underwent non-myeloablative allografting, 10 as part of their initial treatment and 12 at relapse. Donors were matched for HLA-A, B, C, DRB1 and DQB1 by high-resolution typing. Only one single class I allele disparity was allowed. Conditioning consisted of fludarabine 90 mg/m(2) and 2 Gy total body irradiation. Graft-vs.-host disease (GVHD) prophylaxis included cyclosporin and mycophenolate mofetil.

RESULTS

All patients except two (91%) readily engrafted. After a median follow-up of 20 (10-30) months, incidences of grade II-IV acute and extensive chronic GVHD were 50% and 61%. Overall response (OR) was 55%, with four (20%) complete and seven (35%) partial remissions. However, in patients allografted up-front OR was 89% whereas in the heavily pretreated group OR was 27% (P = 0.01). Two-year overall and event-free survivals were both 79% in the group transplanted up-front and 27% and 25% among relapsed patients (P = 0.025 and P = 0.006, respectively). Overall, six patients died of TRM and three of disease progression.

CONCLUSIONS

Unrelated donor non-myeloablative allografting is feasible in myeloma. Disease control appears more pronounced when patients are treated soon after diagnosis.

A single-chain Fv diabody against human leukocyte antigen-A molecules specifically induces myeloma cell death in the bone marrow environment

Cross-linked human leukocyte antigen (HLA) class I molecules have been shown to mediate cell death in neoplastic lymphoid cells. However, clinical application of an anti-HLA class I antibody is limited by possible side effects due to widespread expression of HLA class I molecules in normal tissues. To reduce the unwanted Fc-mediated functions of the therapeutic antibody, we have developed a recombinant single-chain Fv diabody (2D7-DB) specific to the alpha2 domain of HLA-A. Here, we show that 2D7-DB specifically induces multiple myeloma cell death in the bone marrow environment. Both multiple myeloma cell lines and primary multiple myeloma cells expressed HLA-A at higher levels than normal myeloid cells, lymphocytes, or hematopoietic stem cells. 2D7-DB rapidly induced Rho activation and robust actin aggregation that led to caspase-independent death in multiple myeloma cells. This cell death was completely blocked by Rho GTPase inhibitors, suggesting that Rho-induced actin aggregation is crucial for mediating multiple myeloma cell death. Conversely, 2D7-DB neither triggered Rho-mediated actin aggregation nor induced cell death in normal bone marrow cells despite the expression of HLA-A. Treatment with IFNs, melphalan, or bortezomib enhanced multiple myeloma cell death induced by 2D7-DB. Furthermore, administration of 2D7-DB resulted in significant tumor regression in a xenograft model of human multiple myeloma. These results indicate that 2D7-DB acts on multiple myeloma cells differently from other bone marrow cells and thus provide the basis for a novel HLA class I-targeting therapy against multiple myeloma.

Efficacy and safety of thalidomide in patients with hepatocellular carcinoma

AIM: To evaluate which patients with hepatocellular carcinoma (HCC) are most likely to respond to thalidomide treatment.

METHODS: From July 2002 to July 2004, patients with HCC who received thalidomide treatment, were enrolled. We extracted relevant data from the patients’ medical records, including history and type of hepatitis, comorbidity, serum α-fetoprotein (α-FP) level, volumetric changes in tumor, length of survival, and the dose, duration, side effects of thalidomide treatment. The tumor response was evaluated. On the basis of these data, the patients were divided into two groups: those with either partial response or stable disease (PR + SD group) and those with progressive disease (PD group).

RESULTS: Two of 42 (5%) patients had a partial tumor response after treatment with thalidomide, 200 mg/d, and 9 (21%) had stable disease. Patients in the PR + SD group all had cirrhosis. Comparing patients with and without cirrhosis, the former were more likely to respond to thalidomide therapy (PR + SD: 100% vs PD: 64.5%, P = 0.041 < 0.05). Thalidomide was significantly more likely to be effective in tumors smaller than 5 cm (PR + SD: 63.6% vs PD: 25.8%, P = 0.034 < 0.05). Compared with patients with progressive disease (PD), patients in the PR + SD group had a higher total dose of thalidomide (13 669.4 ± 8446.0 mg vs 22 022.7 ± 11 461.4 mg, P = 0.023 < 0.05) and a longer survival (181.0 ± 107.1 d vs 304.4 ± 167.1 d, P = 0.047 < 0.05). Patients with comorbid disease had a significantly greater incidence of adverse reactions than those without (93.8% vs 60.0%, P = 0.021 < 0.05). The average number of adverse reactions in each person with a comorbid condition was twice as high as in those without other diseases (2.2 ± 1.3 vs 1.1 ± 1.2; P = 0.022 < 0.05).

CONCLUSION: Thalidomide therapy is most likely to be effective in patients with early stage small HCC, especially in those with other underlying diseases. A low dose (200 mg/d) of thalidomide is recommended to continue the treatment long enough to make it more effective.

Serological identification and bioinformatics analysis of immunogenic antigens in multiple myeloma

Identifying appropriate tumor antigens is critical to the development of successful specific cancer immunotherapy. Serological analysis of tumor antigens by a recombinant cDNA expression library (SEREX) allows the systematic cloning of tumor antigens recognized by the spontaneous autoantibody repertoire of cancer patients. We applied SEREX to the cDNA expression library of cell line HMy2, which led to the isolation of six known characterized genes and 12 novel genes. Known genes, including ring finger protein 167, KLF10, TPT1, p02 protein, cDNA FLJ46859 fis, and DNMT1, were related to the development of different tumors. Bioinformatics was performed to predict 12 novel MMSA (multiple myeloma special antigen) genes. The prediction of tumor antigens provides potential targets for the immunotherapy of patients with multiple myeloma (MM) and help in the understanding of carcinogenesis. Crude lysate ELISA methodology indicated that the optical density value of MMSA-3 and MMSA-7 were significantly higher in MM patients than in healthy donors. Furthermore, SYBR Green real-time PCR showed that MMSA-1 presented with a high number of copy messages in MM. In summary, the antigens identified in this study may be potential candidates for diagnosis and targets for immunotherapy in MM.

Improved antitumoral properties of pure antiestrogen RU 58668-loaded liposomes in multiple myeloma

In most of multiple myeloma (MM) cells, the "pure" antiestrogen (AE) RU 58668 (RU) induced either a G1-arrest (LP-1, OPM-2, NCI-H929, U266 cells) or apoptosis (RPMI 8226 cells). In RPMI 8226 cells, RU activates a caspase-dependent cell death pathway leading to the release of cytochrome c, the decrease of the essential MM survival factor Mcl-1, the cleavage of Bid and the activation of caspases-3 and -8. Incorporation of RU in pegylated cholesterol-containing liposomes allowed a controlled RU release, improving its anti-proliferative and apoptotic effects in cells. In RPMI 8226 xenografts, i.v. injected RU-liposomes but not free RU, exhibited antitumor activity. In vivo, RU-liposomes triggered the mitochondrial death pathway, concomitantly with a down-regulation of Mcl-1 and Bid cleavage. The decrease of CD34 immunoreactivity indicated a reduction of angiogenesis. The decrease of VEGF secretion in vitro supported a direct effect of RU on angiogenesis. These pro-apoptotic and antiangiogenic effects were explained by a prolonged exposure to the drug and to the endocytosis capacity of liposomes which might increase RU uptake and bypass a membrane export of free RU. Thus, these combined enhanced activities of RU-liposomes support that such a delivery of an AE may constitute a strategy of benefit for MM treatment.

A practical update on the use of bortezomib in the management of multiple myeloma

Despite intensive therapy, multiple myeloma (MM) remains an incurable disease, and novel treatment approaches are therefore needed to improve outcome. Bortezomib is the first proteasome inhibitor to be approved by the U.S. Food and Drug Administration (FDA) and the European Agency for the Evaluation of Medicinal Products for the treatment of refractory or relapsed MM following the failure of at least two prior lines of therapy. Recently, it also received approval from the FDA for use as a second-line agent. An expert panel of hematologists met at the Ninth Congress of the European Hematology Association to review clinical data and experience in the treatment of MM with bortezomib, including bortezomib-based combination therapy. The conclusions of this expert panel, together with updated clinical data from the American Society of Hematology 46th Annual Meeting, provide a practical update on the use of bortezomib in MM. Bortezomib has demonstrated significant antitumor activity as a single agent in refractory and/or relapsed MM, with a significantly longer survival than with dexamethasone (1-year overall survival rate of 80% vs. 66%) and a 78% longer median time to progression. In combination therapy, patient responses suggest the possibility of chemosensitization and synergy. Furthermore, bortezomib does not appear to have an adverse effect on subsequent stem cell therapy. Bortezomib is well tolerated; most side effects are only mild to moderate and are manageable. Information is given on the practical management of the most common adverse events, including peripheral neuropathy and thrombocytopenia, and the use of bortezomib in renal and hepatic impairment.

Overexpression of survivin in primary ATL cells and sodium arsenite induces apoptosis by down-regulating survivin expression in ATL cell lines

Patients with acute- or lymphoma-type adult T-cell leukemia (ATL) have a poor outcome because of the intrinsic drug resistance to chemotherapy. Protection from apoptosis is a common feature involved in multidrug-resistance of ATL. IAP (inhibitor of apoptosis) family proteins inhibit apoptosis induced by a variety of stimuli. In this study, we investigated the expression of IAP family members (survivin, cIAP1, cIAP2, and XIAP) in the primary leukemic cells from patients with ATL. We found that survivin was overexpressed in ATL, especially in acute-type ATL. Sodium arsenite was shown to down-regulate the expression of survivin at both the protein and RNA levels in a time- and dose-dependent manner, thus inhibiting cell growth, inducing apoptosis, and enhancing the caspase-3 activity in ATL cells. Nuclear factor-κB (NF-κB) enhances the transcriptional activity of survivin. Sodium arsenite suppressed the constitutive NF-κB activation by preventing the IκB-α degradation and the nuclear translocation of NF-κB. These findings suggest that survivin is an important antiapoptotic molecule that confers drug resistance on ATL cells. Sodium arsenite was shown to down-regulate the expression of survivin through the NF-κB pathway, thus inhibiting cell growth and promoting apoptosis of ATL cells.

Targeting signalling pathways for the treatment of multiple myeloma

Multiple myeloma (MM) is characterised by the expansion of monoclonal immunoglobulin-secreting plasma cells. Despite recent advances in systemic and supportive therapy, it remains incurable, with a median survival of about three years. Development of MM is a multistep process associated with an increasing frequency of chromosomal abnormalities and complex translocations, which induce mutations in several proto-oncogenes and tumour suppressor genes. Furthermore, differentiation, maintenance, expansion and drug resistance of MM cells are dependent on multiple growth factors, cytokines, and chemokines, secreted by tumour cells, bone marrow stromal cells, and non-haematopoietic organs; as well as on direct tumour cell-stromal cell contact. Therefore, signalling pathways initiated by both mutated genes in MM cells as well as signals originating in the bone marrow microenvironment represent potential targets for intervention. Close collaboration between basic researchers and clinicians will be required to further improve our knowledge of MM pathophysiologically in order to translate advances from the bench to the bedside and improve patient outcome.

Intermediate-Dose Melphalan (100 mg/m2)/Bortezomib/Thalidomide/Dexamethasone and Stem Cell Support in Patients with Refractory or Relapsed Myeloma

BACKGROUND

Bortezomib and thalidomide have shown synergy with melphalan and dexamethasone. We used this 4-drug combination as conditioning before autologous hematopoietic cell infusions.

PATIENTS AND METHODS

Twenty-six patients with advanced-stage myeloma were treated with melphalan 50 mg/m(2) and bortezomib 1.3 mg/m(2) on days -6 and -3 in association with thalidomide 200 mg and dexamethasone 20 mg on days -6 through -3, followed by hematopoietic cell support on day 0.

RESULTS

Nonhematologic toxicities included pneumonia, febrile neutropenia, and peripheral neuropathy. All patients had undergone autologous transplantation at diagnosis, and 13 patients (50%) underwent an additional transplantation at relapse. Responses occurred in 17 of 26 patients (65%), including 1 complete remission, 3 near complete remissions (12%), and 2 very good partial remissions (8%). Response rate was higher than that induced by the previous line of treatment in 12 patients (46%).

CONCLUSION

Melphalan/bortezomib/thalidomide/dexamethasone showed encouraging antimyeloma activity in patients with advanced-stage myeloma.

Intravenous melphalan, thalidomide and prednisone in refractory and relapsed multiple myeloma

OBJECTIVES

Thalidomide combined with conventional chemotherapies including oral melphalan shows significant anti-myeloma activity. To address this issue, feasibility and efficacy of a three drug combination consisting of intravenous (i.v.) melphalan, thalidomide and prednisone [M(i.v.)PT] was evaluated in advanced myeloma patients.

PATIENTS AND METHODS

Twenty-four advanced myeloma patients were treated with multiple cycles of a regimen consisting of low dose i.v. melphalan (20 mg/m2) at d 1, thalidomide at the dose of 50-100 mg/d given continuously and oral prednisone at the planned dose of 50 mg/d every other day. Intravenous melphalan was administered every fourth month. Median time from diagnosis was 40 months (range: 8-144 months). Fifteen patients (66%) had previously been treated with a combination of thalidomide and dexamethasone or with thalidomide alone.

RESULTS

Overall, on an intent-to treat basis, 14 patients responded: three achieved near complete remission (nCR), seven achieved partial response (PR), four minimal response (MR). Six patients showed stable disease (SD) and four-disease progression. Interestingly, of five patients who had previously progressed while on thalidomide and prednisone, one reached nCR, two PR and one MR. After a median follow up of 14 months, median progression free survival was 9 months. Response duration was longer than that induced by the previous line of treatment in eight patients (33%). Thalidomide-associated toxicity mainly consisted of constipation, tingling and sedation.

CONCLUSIONS

M(i.v.)PT is an effective regimen, which can overcome resistance to thalidomide plus prednisone in advanced myeloma with acceptable toxicity.

Neoplastic circulating endothelial cells in multiple myeloma with 13q14 deletion

In multiple myeloma (MM), circulating endothelial cells (CECs) represent a vascular marker of angiogenesis and may reflect tumor mass. In this report, we showed that, in 5 MM patients with 13q14 deletion, CECs carried the same chromosome aberration as the neoplastic plasma cells (11%-32% of CECs with 13q14 deletion). Most of the CECs displayed immunophenotypic features of endothelial progenitor cells as they expressed CD133, a marker gradually lost during endothelial differentiation and absent on mature endothelial cells. To the contrary, in 3 patients with monoclonal gammopathy of undetermined significance and 13q14 deletion, CECs were cytogenetically normal and had a mature immunophenotype. In MM CECs, immunoglobulin genes were clonally rearranged. These findings suggest a possible origin of CECs from a common hemangioblast precursor that can give rise to both plasma cells and endothelial cells and point to a direct contribution of MM-derived CECs to tumor vasculogenesis and possibly to the spreading and progression of the disease. (Blood. 2006;107:2531-2535)

Molecular targeted therapy: A strategy of disillusions or optimism?

Cytotoxic drugs were designed to kill tumor cells, whereas agents of molecular targeted therapy inhibit various molecular functions of the tumor cell. Consequently, their toxicity profiles also differ. Molecular targeted agents, except for monoclonal antibodies, are enumerated here in three classes: compounds active extracellularly, extra/intracellularly, and intracellularly. Although no major breakthrough has occurred in the drug treatment of neoplastic diseases yet, such compounds as trastuzumab, cetuximab, bevacizumab, gefitinib, erlotinib, imatinib, and bortezomib have shown considerable clinical promise. Major obstacles to the further development of molecular targeted compounds are described. The use of different endpoints, positron emission tomography for evaluation, and predictive genetic markers are recommended. Combination therapy with cytotoxic drugs and studies in an adjuvant setting are also recommended. It is concluded that cautious optimism about the future of molecular targeted therapy is reasonable.

Identification of the angiogenic endothelial-cell growth factor-1/thymidine phosphorylase as a potential target for immunotherapy of cancer

Characterization of the antigens recognized by tumor-reactive T cells isolated from patients successfully treated with allogeneic HLA-matched hematopoietic stem cell transplantation (SCT) can lead to the identification of clinically relevant target molecules. We isolated tumor-reactive cytotoxic CD8(+) T-cell (CTL) clones from a patient successfully treated with donor lymphocyte infusion for relapsed multiple myeloma after allogeneic HLA-matched SCT. Using cDNA expression cloning, the target molecule of an HLA-B7-restricted CTL clone was identified. The CTL clone recognized a minor histocompatibility antigen produced by a single nucleotide polymorphism (SNP) in the angiogenic endothelial-cell growth factor-1 (ECGF1) gene also known as thymidine phosphorylase. The SNP leads to an Arg-to-His substitution in an alternatively translated peptide that is recognized by the CTL. The ECGF1 gene is predominantly expressed in hematopoietic cells, although low expression can also be detected in other tissues. The patient from whom this CTL clone was isolated had mild graft-versus-host disease despite high numbers of circulating ECGF-1-specific T cells as detected by tetramer staining. Because solid tumors expressing ECGF-1 could also be lysed by the CTL, ECGF-1 is an interesting target for immunotherapy of both hematologic and solid tumors.

2-methoxyestradiol induces apoptosis in cultured human anaplastic thyroid carcinoma cells

Anaplastic thyroid carcinoma (ATC) is one of the most malignant tumors in humans, and currently there is no effective treatment. In the present study we investigated the effect of an endogenous estrogen metabolite, 2-methoxyestradiol (2-ME), on the growth of human ATC cells. 2-ME treatment had a strong growth inhibitory effect on five human ATC cell lines (HTh7, HTh 74, HTh83, C643, and SW1736), but showed no effect on one cell line (KAT-4). Cell cycle analysis of the growth-inhibited cells showed that 2-ME induced a G2/M-arrest, followed by an increased fraction of cells in sub-G1. Analysis of internucleosomal DNA laddering as well as DNA fragmentation in a terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) assay demonstrated a high number of cells undergoing apoptosis after 2-ME treatment. An increased activation of caspase-3 and caspase-8 by 2-ME was observed, and inhibition of caspase-3 decreased the apoptotic effect. Addition of 2-ME increased activity of p38 mitogen-activated protein kinase (MAPK) in the sensitive HTh7 as well as the refractory KAT-4 cells, however, activation of stress-activated protein kinase/c-jun aminoterminal kinase (SAPK/JNK) was seen only in the HTh7 cells. Inhibitors of p38 MAPK and SAPK/JNK significantly attenuated the 2-ME effect. Taken together, our data demonstrate an antiproliferative and apoptotic effect of 2-ME on ATC cells involving activation of MAPKs.

Execution of BMP-4-induced apoptosis by p53-dependent ER dysfunction in myeloma and B-cell hybridoma cells

Bone morphogenic protein (BMP)-4 inhibits proliferation and induces the apoptosis of myeloma cells. However, little is known about the molecular mechanisms of how BMP-4 executes this apoptosis. In this report, we investigated the roles of p53 and the endoplasmic reticulum (ER) in BMP-4-induced apoptosis of mouse hybridoma HS-72 cells. We found that 3 ng/ml of BMP-4 is sufficient to induce the expression of proapoptotic proteins, puma and bax, in a p53-dependent mechanism, and facilitate Ca(2+) release from the ER to the cytosol, resulting in the activation of caspase-12 and ER dysfunction. Similarly to HS-72 cells, multiple myeloma cells with wild-type p53 genes show much higher sensitivity to BMP-4-induced apoptosis than cells without wild-type p53 genes, suggesting that wild-type p53 status is required for dysfunction of the ER during BMP-4-induced apoptosis in ER-enriched cells, such as hybridoma and myeloma cells. These findings demonstrate that the presence of wild-type p53 genes and enrichment of the ER determines the sensitivity to effective apoptosis by BMP-4, and suggest that ER stress-inducing agents would be valuable in the treatment of multiple myeloma.

Unilateral diaphragm paralysis possibly due to cervical spine involvement in multiple myeloma

OBJECTIVE

To describe a patient with unilateral diaphragmatic paralysis due to multiple myeloma (MM) involving the cervical spine and related structures.

CASE PRESENTATION AND INTERVENTION

A 52-year-old female presented with dyspnea, low back and widespread bone pain. She was diagnosed as having MM with vertebral involvement and unilateral paralysis of the diaphragm. She received two cycles of a chemotherapeutic regimen consisting of vincristine-Adriamycin-dexamethasone. The bisphosphonate zoledronic acid was also initiated at the same time. During follow-up, the back pain disappeared and the complaint of dyspnea decreased, although the paralysis persisted.

CONCLUSION

As part of the differential diagnosis of bone and back pain, we draw attention to MMand the rare complication of diaphragmatic paralysis due to phrenic nerve involvement.

Targeted therapy in multiple myeloma

BACKGROUND

Multiple myeloma (MM) is an incurable malignancy. Recent insights into its biology has allowed the use of novel therapies targeting not only the deregulated intracellular signaling in MM cells but also its interaction with the bone marrow microenvironment that confers drug resistance, growth, and survival advantage to the malignant cells.

METHODS

We review and summarize the recent advances in our knowledge of myeloma biology as well as the mechanism of action and clinical efficacy for novel therapeutic agents in clinical trials.

RESULTS

Several novel therapeutic agents are currently in clinical trials. Thalidomide is already established for both initial and salvage treatment. Bortezomib is being tested alone and in combination with conventional chemotherapy in various settings. Other agents are less effective in producing response but have been able to stabilize disease in patients with relapsed and/or refractory disease, such as arsenic trioxide, farnesyltransferase inhibitors, 2-methoxyestradiol, and vascular endothelial growth factor receptor inhibitors. Insights into drug resistance mechanism have also led to the development of novel agents that sensitize myeloma cells to chemotherapy (Bcl-2 antisense). Gene expression studies have in many instances identified pathways other than the intended target of the drug and have provided insights into the therapeutic mechanisms.

CONCLUSIONS

In the future, patients with MM will have more therapeutic options available than ever before. The challenge will be to identify patient subgroups that will benefit most from the different therapies and then determine how these biologically based therapies could be combined and incorporated into the overall management of patients.

Problems monitoring response in multiple myeloma

There has been a revolution in the treatment of multiple myeloma over the past decade. This article seeks to correlate advances in imaging with advances in treatment and to highlight how proper understanding of both is necessary for optimum management.

A crosstalk between myeloma cells and marrow stromal cells stimulates production of DKK1 and interleukin-6: a potential role in the development of lytic bone disease and tumor progression in multiple myeloma

Multiple myeloma (MM) is a malignancy of antibody-secreting plasma cells. B-cell plasmacytomas stimulate bone resorption and angiogenesis, resulting in osteolytic lesions in the skeleton which persist upon successful treatment of the malignancy with chemotherapy. We found that an interaction between MM cells and mesenchymal stem cells (MSCs) from bone marrow stroma results in the formation and persistence of osteolytic bone lesions. It is known that MM cells activate osteoclast activity and secrete high levels of the Wnt inhibitor, Dickkopf-1, which prevents MSCs from differentiating into osteoblasts. We show that the Wnt signaling activator 6-bromoindirubin-3'-monoxime (BIO) releases MSCs from the osteoinhibitory effects of Dickkopf-1, whereas LiCl treatment does not. Additionally, we show that the >5-kDa fraction of MSC-conditioned medium promotes the proliferation of Dickkopf-1-secreting MM cells and that an interleukin-6 (IL-6)-neutralizing antibody blocks this effect. IL-6 expression levels were higher in undifferentiated MSCs than in MSCs treated with osteogenic medium, remained high in the presence of Dkk1, and were reduced by BIO treatment. Therefore, BIO treatment reduces the MSC-stimulated proliferation of MM cells and may enable MSCs to repair existing osteolytic lesions.

RUNX3, a novel tumor suppressor, is frequently inactivated in gastric cancer by protein mislocalization

Loss of RUNX3 expression is suggested to be causally related to gastric cancer as 45% to 60% of gastric cancers do not express RUNX3 mainly due to hypermethylation of the RUNX3 promoter. Here, we examined for other defects in the properties of RUNX3 in gastric cancers that express RUNX3. Ninety-seven gastric cancer tumor specimens and 21 gastric cancer cell lines were examined by immunohistochemistry using novel anti-RUNX3 monoclonal antibodies. In normal gastric mucosa, RUNX3 was expressed most strongly in the nuclei of chief cells as well as in surface epithelial cells. In chief cells, a significant portion of the protein was also found in the cytoplasm. RUNX3 was not detectable in 43 of 97 (44%) cases of gastric cancers tested and a further 38% showed exclusive cytoplasmic localization, whereas only 18% showed nuclear localization. Evidence is presented suggesting that transforming growth factor-beta is an inducer of nuclear translocation of RUNX3, and RUNX3 in the cytoplasm of cancer cells is inactive as a tumor suppressor. RUNX3 was found to be inactive in 82% of gastric cancers through either gene silencing or protein mislocalization to the cytoplasm. In addition to the deregulation of mechanisms controlling gene expression, there would also seem to be at least one other mechanism controlling nuclear translocation of RUNX3 that is impaired frequently in gastric cancer.

Continuous prednisolone versus conventional prednisolone with VMCP-interferon-alpha2b as first-line chemotherapy in elderly patients with multiple myeloma

We report on a randomised trial that aimed to compare the efficacy of continued daily prednisolone treatment during the entire induction phase, with prednisolone given for 2 weeks of each cycle in combination with VMCP (vincristine, melphalan, cyclophosphamide, prednisolone)-interferon-alpha 2b (IFN-alpha 2b) treatment in 299 previously untreated elderly patients (median age: 67 years) with multiple myeloma. After completion of induction treatment patients were randomised to IFN-alpha 2b with or without prednisolone, thrice weekly. Response rate was 62% in the continuous and 60% in the control arm (intent to treat analysis, P=0.81). Progression-free survival [median: 20 months vs. 19 months; hazard ratio (HR): 0.99, 95% confidence interval (CI): 0.74-1.33, P=0.97] and overall survival (median: 34 months vs. 37 months; HR: 1.16, 95% CI: 0.85-1.59, P=0.35) were similar in both groups. Reduced performance status (Eastern Cooperative Oncology Group, grades 2-4) was the predominant risk factor for poor survival followed by age >65 years, high beta2-microglobulin, and impaired renal function. There was more grades 3-4 dyspnoea and cardiac impairment and grades 1-2 hyperglycaemia, but less nausea, emesis and anaemia in patients on continuous prednisolone therapy. In conclusion, continuing prednisolone treatment during the entire duration of the induction phase with VMCP-IFN-alpha 2b did not improve outcome.

Novel targeted drugs for the treatment of multiple myeloma: from bench to bedside

Multiple myeloma remains an incurable plasma cell neoplasm. New insights into its pathogenesis have identified signaling pathways that have become potential therapeutic targets. It has clearly been established that intracellular regulatory proteins and interactions between malignant plasma cells and the bone marrow microenvironment play an important role in their survival and drug resistance. Several new agents associated with molecular targets are currently being investigated to design new treatment strategies aimed at prolonging survival and improving quality of life. This review illustrates their mechanisms of action and the possible future clinical applications.

Preclinical evaluation of the proteasome inhibitor bortezomib in cancer therapy

Bortezomib is a highly selective, reversible inhibitor of the 26S proteasome that is indicated for single-agent use in the treatment of patients with multiple myeloma who have received at least 2 prior therapies and are progressing on their most recent therapy. Clinical investigations have been completed or are under way to evaluate the safety and efficacy of bortezomib alone or in combination with chemotherapy in multiple myeloma, both at relapse and presentation, as well as in other cancer types. The antiproliferative, proapoptotic, antiangiogenic, and antitumor activities of bortezomib result from proteasome inhibition and depend on the altered degradation of a host of regulatory proteins. Exposure to bortezomib has been shown to stabilize p21, p27, and p53, as well as the proapoptotic Bid and Bax proteins, caveolin-1, and inhibitor kappaB-alpha, which prevents activation of nuclear factor kappaB-induced cell survival pathways. Bortezomib also promoted the activation of the proapoptotic c-Jun-NH2 terminal kinase, as well as the endoplasmic reticulum stress response. The anticancer effects of bortezomib as a single agent have been demonstrated in xenograft models of multiple myeloma, adult T-cell leukemia, lung, breast, prostate, pancreatic, head and neck, and colon cancer, and in melanoma. In these preclinical in vivo studies, bortezomib treatment resulted in decreased tumor growth, angiogenesis, and metastasis, as well as increased survival and tumor apoptosis. In several in vitro and/or in vivo cancer models, bortezomib has also been shown to enhance the antitumor properties of several antineoplastic treatments. Importantly, bortezomib was generally well tolerated and did not appear to produce additive toxicities when combined with other therapies in the dosing regimens used in these preclinical in vivo investigations. These findings provide a rationale for further clinical trials using bortezomib alone or in combination regimens with chemotherapy, radiation therapy, immunotherapy, or novel agents in patients with hematologic malignancies or solid tumors.