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Leukemia & Lymphoma 2015Milatuzumab (hLL1), a humanized anti-CD74 monoclonal antibody, has activity in preclinical non-Hodgkin lymphoma (NHL) models. We conducted a phase 1 trial in previously...
Milatuzumab (hLL1), a humanized anti-CD74 monoclonal antibody, has activity in preclinical non-Hodgkin lymphoma (NHL) models. We conducted a phase 1 trial in previously treated B-cell malignancies. Dose escalation included four planned dose levels (1.5, 4, 6 and 8 mg/kg) with milatuzumab given twice weekly for 6 weeks. After dose level 1, the schedule was changed to daily (Monday-Friday) for 10 days. Twenty-two patients were treated. The most common possibly related toxicities were infusion reaction, anemia, lymphopenia, neutropenia and thrombocytopenia. Three patients experienced dose-limiting toxicity (neutropenia, neutropenia, rash) at dose levels 1, 2 and 4, respectively. Eight patients had stable disease, with no objective responses. The serum half-life of milatuzumab was ∼2 h. In seven patients, In-111 imaging showed no clear evidence of tumor targeting. The short half-life may reflect CD74 rapid internalization and presence on extratumoral tissues; this antigen sink must be overcome to capitalize on the promising preclinical activity of the drug.
Topics: Adult; Aged; Antibodies, Monoclonal, Humanized; Antigens, Differentiation, B-Lymphocyte; Antineoplastic Agents; Biomarkers; Disease Progression; Drug Resistance, Neoplasm; Female; Histocompatibility Antigens Class II; Humans; Immunohistochemistry; Lymphoma, B-Cell; Male; Middle Aged; Neoplasm Staging; Recurrence; Retreatment; Tissue Distribution; Treatment Outcome
PubMed: 25754579
DOI: 10.3109/10428194.2015.1028052 -
Journal of Experimental & Clinical... Oct 2014Resistance to Fas-mediated apoptosis limits the efficacy of currently available chemotherapy regimens. We identified CD74, which is known to be overexpressed in...
BACKGROUND
Resistance to Fas-mediated apoptosis limits the efficacy of currently available chemotherapy regimens. We identified CD74, which is known to be overexpressed in hematological malignancies, as one of the factors interfering with Fas-mediated apoptosis.
METHODS
CD74 expression was suppressed in human B-lymphoma cell lines, BJAB and Raji, by either transduction with lentivirus particles or transfection with episomal vector, both encoding CD74-specific shRNAs or non-target shRNA. Effect of CD74 expression on Fas signaling was evaluated by comparing survival of mice hydrodynamically transfected with vector encoding full-length CD74 or empty vector. Sensitivity of cells with suppressed CD74 expression to FasL, edelfosine, doxorubicin, and a humanized CD74-specific antibody, milatuzumab, was evaluated by flow cytometry and compared to control cells. Fas signaling in response to FasL stimulation and the expression of Fas signaling components were evaluated by Western blot. Surface expression of Fas was detected by flow cytometry.
RESULTS
We determined that cells with suppressed CD74 are more sensitive to FasL-induced apoptosis and Fas signaling-dependent chemotherapies, edelfosine and doxorubicin, than control CD74-expressing cells. On the other hand, expression of full-length CD74 in livers protected the mice from a lethal challenge with agonistic anti-Fas antibody Jo2. A detailed analysis of Fas signaling in cells lacking CD74 and control cells revealed increased cleavage/activation of pro-caspase-8 and corresponding enhancement of caspase-3 activation in the absence of CD74, suggesting that CD74 affects the immediate early steps in Fas signaling at the plasma membrane. Cells with suppressed CD74 expression showed increased staining of Fas receptor on their surface. Pre-treatment with milatuzumab sensitized BJAB cells to Fas-mediated apoptosis.
CONCLUSION
We anticipate that specific targeting of the CD74 on the cell surface will sensitize CD74-expressing cancer cells to Fas-mediated apoptosis, and thus will increase effectiveness of chemotherapy regimens for hematological malignancies.
Topics: Animals; Antibodies, Monoclonal, Humanized; Antigens, Differentiation, B-Lymphocyte; Antineoplastic Agents; Apoptosis; Dose-Response Relationship, Drug; Doxorubicin; Fas Ligand Protein; Histocompatibility Antigens Class II; Humans; Jurkat Cells; Liver; Lymphoma, B-Cell; Mice, Inbred C57BL; Phospholipid Ethers; RNA Interference; Signal Transduction; Transfection; fas Receptor
PubMed: 25304249
DOI: 10.1186/s13046-014-0080-y -
Expert Opinion on Investigational Drugs Jul 2014Antibody-drug conjugates (ADCs) are mAb attached to biologically active drugs through specialized chemical linkers with labile bonds. They deliver the cytotoxic agent... (Review)
Review
INTRODUCTION
Antibody-drug conjugates (ADCs) are mAb attached to biologically active drugs through specialized chemical linkers with labile bonds. They deliver the cytotoxic agent and release it at the tumor with limited systemic exposure.
AREAS COVERED
In this review, the authors summarize and discuss antibody conjugates in Phase II clinical trials in lymphoid malignancies. Furthermore, the article gives a critical overview of Phase II clinical trials of these therapies.
EXPERT OPINION
ADCs have increased selectivity and a longer half-life in comparison to systemic chemotherapy. These agents improve the potency of chemotherapy by increasing the accumulation of the cytotoxic drug within neoplastic cells with reduced systemic effects. Improvements in cytotoxin selection and the use of partial antibodies have further improved the clinical value of ADCs. Newer ADCs currently in Phase II clinical trials show promise as treatments for several lymphoid malignancies, especially lymphoma, multiple myeloma and lymphoid leukemia. In the near future, the addition of ADCs to the armamentarium of anticancer drugs should offer novel and more targeted treatment strategies.
Topics: Animals; Antibodies, Monoclonal; Antineoplastic Agents; Clinical Trials as Topic; Humans; Immunoconjugates; Leukemia; Lymphoma; Multiple Myeloma
PubMed: 24708159
DOI: 10.1517/13543784.2014.908184 -
British Journal of Haematology Apr 2014
Topics: Animals; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Apoptosis; Humans; Lymphoma, Follicular; MAP Kinase Signaling System; Mice; NF-kappa B
PubMed: 24386925
DOI: 10.1111/bjh.12711 -
British Journal of Haematology Nov 2013CD74, expressed in multiple myeloma (MM), was evaluated as a target for immunotherapy with milatuzumab (a humanized anti-CD74 antibody). In a multicentre dose escalation...
CD74, expressed in multiple myeloma (MM), was evaluated as a target for immunotherapy with milatuzumab (a humanized anti-CD74 antibody). In a multicentre dose escalation study, 25 patients with advanced MM received milatuzumab doses of 1.5 (N = 8), 4.0 (N = 9), 8.0 (N = 4) or 16.0 mg/kg (N = 4) administered twice weekly x 4. They had a median of 5 prior treatments (17 post ≥ 1 stem cell transplantation) and were refractory (N = 7) or relapsed (N = 18) with generally short-lived responses to last treatment (median 4.0 months). After increasing prophylactic medications and slowing administration, infusions were well tolerated (National Cancer Institute-Common Terminology Criteria v3 toxicity Grades 1-2) with no dose-limiting toxicity at higher doses. Only one patient developed borderline positive human anti-milatuzumab antibody titres of uncertain clinical significance. Although milatuzumab was rapidly cleared from circulation with little serum accumulation and low trough levels, B-cell levels were moderately decreased with treatment (median decrease, 34%). There were no objective responses by European Group for Blood and Marrow Transplantation criteria, but 5 of 19 patients (26%) who completed treatment in this heavily pretreated and generally refractory group had stable disease for ≥ 3 months post-treatment (one continuing for 17 months). Disease stabilization and evidence of pharmacodynamic activity support further development for use in combination with other agents or as a drug conjugate.
Topics: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal, Humanized; Antigens, Differentiation, B-Lymphocyte; Dose-Response Relationship, Drug; Female; Histocompatibility Antigens Class II; Humans; Male; Middle Aged; Multiple Myeloma; Recurrence
PubMed: 24112026
DOI: 10.1111/bjh.12565 -
Oncogene Feb 2014Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of CD5+ B lymphocytes in peripheral blood, lymphoid organs and bone marrow. The main feature of...
Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of CD5+ B lymphocytes in peripheral blood, lymphoid organs and bone marrow. The main feature of the disease is accumulation of the malignant cells due to decreased apoptosis. CD84 belongs to the signaling lymphocyte activating molecule family of immunoreceptors, and has an unknown function in CLL cells. Here, we show that the expression of CD84 is significantly elevated from the early stages of the disease, and is regulated by macrophage migration inhibitory factor and its receptor, CD74. Activation of cell surface CD84 initiates a signaling cascade that enhances CLL cell survival. Both downmodulation of CD84 expression and its immune-mediated blockade induce cell death in vitro and in vivo. In addition, analysis of samples derived from an on-going clinical trial, in which human subjects were treated with humanized anti-CD74 (milatuzumab), shows a decrease in CD84 messenger RNA and protein levels in milatuzumab-treated cells. This downregulation was correlated with reduction of Bcl-2 and Mcl-1 expression. Thus, our data show that overexpression of CD84 in CLL is an important survival mechanism that appears to be an early event in the pathogenesis of the disease. These findings suggest novel therapeutic strategies based on the blockade of this CD84-dependent survival pathway.
Topics: Antigens, CD; Antigens, Differentiation, B-Lymphocyte; Apoptosis; Base Sequence; Case-Control Studies; Cell Line, Tumor; Cell Survival; DNA Primers; Histocompatibility Antigens Class II; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; Signaling Lymphocytic Activation Molecule Family
PubMed: 23435417
DOI: 10.1038/onc.2013.31 -
Molecular Cancer Therapeutics Jun 2013CD74 is an attractive target for antibody-drug conjugates (ADC), because it internalizes and recycles after antibody binding. CD74 mostly is associated with hematologic...
CD74 is an attractive target for antibody-drug conjugates (ADC), because it internalizes and recycles after antibody binding. CD74 mostly is associated with hematologic tumors but is expressed also in solid cancers. Therefore, ADCs of the humanized anti-CD74 antibody, milatuzumab, were examined for the therapy of CD74-expressing solid tumors. Milatuzumab-doxorubicin and two milatuzumab-SN-38 conjugates with cleavable linkers, differing in their stability in serum and how they release SN-38 in the lysosome, were prepared. CD74 expression was determined by flow cytometry and immunohistology. In vitro cytotoxicity and in vivo therapeutic studies were conducted in the human cancer cell lines A-375 (melanoma), HuH-7 and Hep-G2 (hepatoma), Capan-1 (pancreatic), NCI-N87 (gastric), and Raji Burkitt lymphoma. The milatuzumab-SN-38 ADC was compared with SN-38 ADCs prepared with anti-Trop-2 and anti-CEACAM6 antibodies in xenografts expressing their target antigens. Milatuzumab-doxorubicin was most effective in the lymphoma model, whereas in A-375 and Capan-1 solid tumors, only milatuzumab-SN-38 showed a therapeutic benefit. Despite much lower surface expression of CD74 than Trop-2 or CEACAM6, milatuzumab-SN-38 had similar efficacy in Capan-1 as anti-Trop-2-SN-38, but in NCI-N87, anti-CEACAM6 and anti-Trop-2 conjugates were superior. Studies in two hepatoma lines at a single dose level showed significant benefit over saline controls but not against an irrelevant immunoglobulin G conjugate. CD74 is a suitable target for ADCs in some solid tumor xenografts, with efficacy largely influenced by uniformity of CD74 expression and with SN-38 conjugates providing the best therapeutic responses; SN-38 conjugates were preferable in solid cancers, whereas doxorubicin ADC was better in lymphoma tested.
Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antigens, Differentiation, B-Lymphocyte; Antigens, Neoplasm; Camptothecin; Cell Adhesion Molecules; Doxorubicin; Gene Expression Regulation, Neoplastic; Hep G2 Cells; Histocompatibility Antigens Class II; Humans; Irinotecan; Neoplasms; Xenograft Model Antitumor Assays
PubMed: 23427296
DOI: 10.1158/1535-7163.MCT-12-1170 -
Clinical Cancer Research : An Official... Jan 2013Corticosteroids are widely used for the treatment of B-cell malignancies, including non-Hodgkin lymphoma, chronic lymphocytic leukemia (CLL), and acute lymphoblastic...
PURPOSE
Corticosteroids are widely used for the treatment of B-cell malignancies, including non-Hodgkin lymphoma, chronic lymphocytic leukemia (CLL), and acute lymphoblastic leukemia; however, this class of drug is associated with undesirable off-target effects. Herein, we developed novel milatuzumab-conjugated liposomes as a targeted dexamethasone carrier for therapeutic delivery in CD74(+) B-cell malignancies and explored its effect against the disease.
EXPERIMENTAL DESIGN
The targeting efficiency of milatuzumab-targeted liposomes to CD74(+) cells was evaluated in vitro. The effect of CD74-targeted liposomal dexamethasone was compared with free dexamethasone in primary CLL cells and cell lines in vitro. The therapeutic efficacy of CD74-targeted liposomal dexamethasone was evaluated in a Raji-severe combined immunodeficient (SCID) xenograft model in vivo.
RESULTS
Milatuzumab-targeted liposomes promoted selective incorporation of carrier molecules into transformed CD74-positive B cells as compared with CD74-negative T-cells. The CD74-dexamethasone-targeted liposomes (CD74-IL-DEX) promoted and increased killing in CD74-positive tumor cells and primary CLL cells. Furthermore, the targeted drug liposomes showed enhanced therapeutic efficacy against a CD74-positive B-cell model as compared with free, or non-targeted, liposomal dexamethasone in SCID mice engrafted with Raji cells in vivo.
CONCLUSIONS
These studies provide evidence and support for a potential use of CD74-targeted liposomal dexamethasone as a new therapy for B-cell malignancies.
Topics: Animals; Antibodies, Monoclonal, Humanized; Antigens, Differentiation, B-Lymphocyte; Cell Line, Tumor; Dexamethasone; Disease Models, Animal; Female; Histocompatibility Antigens Class II; Humans; Leukemia, B-Cell; Liposomes; Lymphoma, B-Cell; Mice; Tumor Burden; Xenograft Model Antitumor Assays
PubMed: 23209030
DOI: 10.1158/1078-0432.CCR-12-2046 -
Biology of Blood and Marrow... Jan 2013Prevention and treatment of graft-versus-host disease (GVHD) remains a major challenge, given that current T-cell depletion and mainstay immunosuppressive therapies... (Clinical Trial)
Clinical Trial
Prevention and treatment of graft-versus-host disease (GVHD) remains a major challenge, given that current T-cell depletion and mainstay immunosuppressive therapies compromise preexisting T-cell immunity, often leading to severe infections and disease relapse. Thus, there is a critical need for novel anti-GVHD agents that can spare protective T-cell memory. Here we show that milatuzumab (hLL1), a humanized anti-CD74 antagonist monoclonal antibody, can moderately reduce the numbers of CD74-expressing B cells and myeloid dendritic cells, but has no effect on the survival of T cells that are CD74(-). Consequently, milatuzumab inhibits allogeneic T-cell proliferation in mixed leukocyte reactions. In a human/mouse xenogeneic SCID mouse model in which GVHD is induced and mediated by engrafted human CD4(+) T cells and dendritic cells, milatuzumab effectively prevents the onset and manifestations of acute GVHD, suppresses serum levels of human IFN-γ and IL-5, eliminates the infiltration of human lymphocytes into GVHD target organs (ie, lung, liver, and spleen), and significantly promotes survival (90% versus 20% for controls; P = .0012). Importantly, exposure to milatuzumab does not affect the number of cytomegalovirus-specific, IFN-γ-producing human CD8(+) T cells in allogeneic mixed leukocyte reactions. These encouraging results warrant further exploration of milatuzumab as a possible new therapeutic agent for GVHD.
Topics: Animals; Antibodies, Monoclonal, Humanized; Antigens, Differentiation, B-Lymphocyte; B-Lymphocytes; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Dendritic Cells; Disease Models, Animal; Female; Graft vs Host Disease; Histocompatibility Antigens Class II; Humans; Interferon-gamma; Interleukin-5; Male; Mice; Mice, SCID; Transplantation, Heterologous
PubMed: 23025988
DOI: 10.1016/j.bbmt.2012.09.015 -
International Journal of Urology :... Feb 2013This study aimed to identify the clinicopathological features of bladder cancer patients with high CD74 expression, as milatuzumab humanized anti-CD74 antibody is being... (Comparative Study)
Comparative Study
This study aimed to identify the clinicopathological features of bladder cancer patients with high CD74 expression, as milatuzumab humanized anti-CD74 antibody is being evaluated in clinical trials for hematological malignancies. Expression of CD74 was examined in 342 urothelial carcinomas of the bladder, and two urothelial carcinoma cell lines by immunohistochemistry and western blotting, respectively. CD74 was overexpressed in 192 (56.1%) of the 342 cancer tissues, although it was not expressed in the cancer cell lines. CD74 staining was intense in tumor cells and inflammatory cells in the tumor stroma, but not in normal urothelium. CD74 expression was significantly associated with older age at diagnosis (≥ 68 years, P=0.048), high World Health Organization grade (P=0.019), advanced stages (P=0.001) and non-papillary growth pattern (P=0.040). CD74 expression was also correlated with the absence of tumor-infiltrating inflammatory cells (P<0.001) and the presence of tumor-associated inflammatory cells (P=0.017). However, CD74 expression was not related to recurrence-free and overall survivals in primary and subgroup analyses. In conclusion, urothelial bladder carcinomas with high CD74 expression are characterized by older age, high World Health Organization grade, non-papillary growth and advanced stages.
Topics: Adult; Aged; Aged, 80 and over; Antigens, Differentiation, B-Lymphocyte; Biopsy, Needle; Blotting, Western; Carcinoma, Transitional Cell; Cystectomy; Female; Follow-Up Studies; Gene Expression Regulation, Neoplastic; Histocompatibility Antigens Class II; Humans; Immunohistochemistry; Kaplan-Meier Estimate; Male; Middle Aged; Multivariate Analysis; Neoplasm Grading; Neoplasm Invasiveness; Statistics, Nonparametric; Survival Analysis; Treatment Outcome; Urinary Bladder Neoplasms; Young Adult
PubMed: 22905972
DOI: 10.1111/j.1442-2042.2012.03128.x