Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Elimination of tumor cells from hematopoietic stem cell products is a major goal of bone marow-suported high-dose cancer chemotherapy. In patients (pts) with low-grade lymphoma Gianni et al (2000) assessed the ability of Rituximab, given in combination with high-dose chemotherapy, to eradicate PCR-detectable disease and enable the harvesting of large amounts of uncontaminated circulating progenitor cells. Our study was conducted in 27 consecutive pts with untreated bcl2 positive NHL (follicular lymphoma--7, chronic lymphocytic leukemia--13 and NHL in leukemic phase--7), 14 pts received Rituximab. Patients received 4 courses of standard-dose chemotherapy (CHOP or FLU-CY), followed by one course of high-dose cyclophosphamid plus G-CSF. Patients allocated to Rituximab received i.v. infusions of 375 mg/m2 48 hours before stem cell collection and in 3 weekly doses after transplantation (R-CHT). Clinical response after transplantation was evaluated in 26 pts who completed the treatment. The complete response rate was in 100% in the Rituximab group (PCR negative in 79%) versus 50% of controls (p<0.01). Yield of purged CD34+ cells was with median 5.23x10(6)/kg in CHT and 8.76x10(6)/kg in R-CHT pts. Toxicity in the both arms was acceptated (no difference). No significant difference was observed between CHT and R-CHT group in the mean number of days spent with neutropenia and trombocytopenia. After a follow-up of 31 months, no patient relapsed. Aside from providing PCR-negative harvests, the chemoimmunotherapy treatment produced complete clinical (100%) and molecular remission in 79% of evaluable pts. We showed that Rituximab in combination with effective high-dose anti- lymphoma chemotherapy, allowed the harvesting of large amounts of tumor free progenitor cells in evaluable pts.
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PMID:Efficiency of in vivo purging with autologous stem cell transplantation and monoclonal antibody in B-cell lymphomas. 1268 74

Indolent non-Hodgkin's lymphomas (NHLs) are essentially incurable with current treatments. Rituximab is a specific anti-CD20 chimeric monoclonal antibody against the CD20 antigen, which is stably expressed on most B-cells (from the pre-B-cell stage). Compared with chemotherapy, rituximab has an excellent tolerability profile, making it a good therapeutic option for patients with indolent NHL. In the pivotal study for rituximab, patients with relapsed or refractory indolent or follicular lymphoma (FL) had an overall response rate of 50%. There is evidence that first-line rituximab therapy may be associated with better response rates; in previously untreated FL with a low tumor burden, rituximab monotherapy has produced an overall response rate of 73%. Attempts to improve response rates to rituximab by increasing the dose or frequency of dosing showed that the addition of four extra infusions of rituximab (in addition to the standard treatment schedule) resulted in an overall response rate of 76% in patients with FL. Augmenting rituximab with cytokines is also an option for increasing response rates in patients with indolent NHL. In a trial by the Nordic Lymphoma Study Group in patients with previously untreated or first-relapse indolent NHL, who had stable disease or a partial response after four doses of rituximab, 48% of the patients treated with rituximab plus interferon-alpha2a achieved a complete response. A further option is to combine rituximab with chemotherapy. Interim analyses from the East German Study Group have shown that rituximab plus mitoxantrone, chlorambucil and prednisolone (MCP) resulted in overall response rates of 89% in patients with untreated indolent lymphoma. Rituximab is therefore an excellent treatment option both as first-line and as salvage therapy for patients with indolent NHL.
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PMID:Rituximab therapy for indolent non-Hodgkin's lymphoma. 1271 May 86

Monoclonal antibody (mAb) therapy (serotherapy) has been successfully used in the treatment of many B-cell malignancies, among them lymphoplasmacytic lymphoma, an uncommon disorder that includes patients with the clinicopathological diagnosis of Waldenstrom's macroglobulinemia (WM). Rituximab, a mAb directed at CD20, was recently demonstrated by us and others to induce remissions and facilitate hematological recovery in patients with WM. The expression of CD20, along with targets of other mAbs which are commercially available, currently in clinical trials, or in preclinical development, have not been extensively studied or well documented in lymphoplasmacytic lymphoma. As such, we examined by flow cytometric analysis tumor cells from a large series of patients with the histopathlogical diagnosis of lymphoplasmacytic lymphoma and the clinicopathological diagnosis of WM for expression of the serotherapy target antigens CD20, CD22, CD40, CD52, IgM, MUC1 core protein, and 1D10. These studies demonstrated antigen expression on >or=50% of bone marrow tumor cells (CD19(+), kappa/lambda light chain-restricted), respectively, from patients as follows: CD20 (98.3%), CD22 (88.3%), CD40 (83.3%), CD52 (77.4%), IgM (83.3%), MUC1 core protein (57.8%), and 1D10 (50%). Both interpatient and intrapatient tumor clone antigen expression was heterogeneous. Combined mAb therapy might be a useful approach to cope with this variation, and could be tailored to target all members of the tumor clone for an individual patient.
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PMID:Expression of serotherapy target antigens in Waldenstrom's macroglobulinemia: therapeutic applications and considerations. 1272 Jan 46

Rituximab is used for in vivo tumor cell purging for non-Hodgkin's lymphoma (NHL) patients prior to autologous peripheral blood stem cell transplantation (PBSCT). However, its effects on PBSC mobilization and function are poorly understood. We compared the mobilization characteristics and engraftment kinetics of 13 NHL patients receiving and 34 NHL patients not receiving rituximab 6 months before PBSC mobilization. In the rituximab group, there was a significantly longer time to neutrophil engraftment (P=0.0466), a trend toward the need for BM harvest to supplement low-yield PBSC collections (31 vs 9%, P=0.08) and a significantly increased rate of bacteremia episodes (62 vs 26%, P=0.025). Median progression-free survival (PFS) and overall survival (OS) were significantly longer in the rituximab compared to the nonrituximab patients (P=0.049 and 0.042, respectively). However, patients in the nonrituximab group were at high risk for recurrence and expected to have shorter survival. Rituximab used within 6 months prior to collection may have a detrimental effect on PBSC mobilization and engraftment. However, rituximab is a major therapeutic breakthrough for NHL treatment and this negative effect may be offset by improved survival. Further studies are warranted in larger populations to determine the impact of rituximab on engraftment, PFS and OS.
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PMID:Effect of rituximab on peripheral blood stem cell mobilization and engraftment kinetics in non-Hodgkin's lymphoma patients. 1283 77

Rituximab is an anti-CD20 chimeric mAb effective for the treatment of B-NHL. It can lyse lymphoma cells in vitro through both C- and Ab-dependent cellular cytotoxicity. The mechanism of action of rituximab in vivo is however still unclear. We have set up a new in vivo model in nonimmunodeficient mice by stable transduction of the human CD20 cDNA in the murine lymphoma line EL4. Animals injected i.v. with the EL4-CD20(+) lymphoma cells died within 30 days with evident liver, spleen, and bone marrow involvement, confirmed by immunohistochemistry and PCR analysis. A single injection of rituximab or the murine anti-CD20 Ab 1F5, given i.p. 1 day after the tumor, cured 100% of the animals. Indeed, at week 4 after tumor cell inoculation, CD20(+) cells were undetectable in all organs analyzed in rituximab-treated animals, as determined by immunohistochemistry and PCR. Rituximab had no direct effect on tumor growth in vitro. Depletion of either NK cells or neutrophils or both in tumor-injected animals did not affect the therapeutic activity of the drug. Similarly, rituximab was able to eradicate tumor cells in athymic nude mice, suggesting that its activity is T cell independent. In contrast, the protective activity of rituximab or the 1F5 Ab was completely abolished in syngeneic knockout animals lacking C1q, the first component of the classical pathway of C (C1qa(-/-)). These data demonstrate that C activation is fundamental for rituximab therapeutic activity in vivo.
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PMID:Complement activation determines the therapeutic activity of rituximab in vivo. 1287 52

A 47-yr-old woman presented a chronic renal failure for 5 yr, with a creatinine clearance of 12 mL/min. In June 2002, she had a right axillary lymph node (of 4 cm diameter). A biopsy revealed a follicular lymphoma (histology: follicular small cleaved-cell). She had Ann Arbor stage III disease, with a high tumor burden according to the GELF criteria. She received rituximab as single first-line treatment (375 mg/m2 by intravenous infusion for a total of four dosages: days 1, 8, 15 and 22). Rituximab therapy was extremely well tolerated, and we obtained a partial response, 4 wk after completing the treatment. In January 2003, she received one maintenance course of rituximab. Six weeks after maintenance therapy, a complete response was achieved.
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PMID:Treatment of a patient with chronic renal failure with rituximab for a follicular lymphoma: safe and successful option of rituximab therapy. 1289 Jan 53

A major limitation in the chemotherapy of cancer results from the lack of tumor specificity displayed by most anticancer drugs. In this regard, a great deal of research has been focused on the development of new chemotherapeutic agents that are able to effectively exploit the differences between neoplastic and normal tissues. Several cancerous tissues and tumors are rich in certain lysosomal enzymes as compared with those found in the normal tissues. Thus, a prodrug can be designed to selectively target such tumor cells where it can be activated to antineoplastic agent by tumor-associated antigen-targeted monoclonal antibody-enzyme conjugate (antibody directed enzyme prodrug therapy strategy) or by the action of an enzyme present at high levels in tumor tissues (prodrug monotherapy strategy). This approach protects the normal cells from the cytotoxic effects of the drug. In the last few years, a number of new MAb-based reagents has been clinically approved (Rituxan, Herceptin and Panorex), and several others are now in advanced clinical trials. This review focuses on the design of several different enzyme/prodrug combinations with an emphasis on mechanistic insight and clinical activity.
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PMID:Selective activation of anthracycline prodrugs for use in conjunction with ADEPT. 1294 62

Monoclonal antibodies used in the treatment of cancer are discussed. Monoclonal antibodies are a new class of agents targeted at specific receptors on cancer cells. In addition to having direct cellular effects, antibodies can carry substances, such as radioactive isotopes, toxins, and antineoplastic agents, to the targeted cells. Five monoclonal antibodies--rituximab, trastuzumab, gemtuzumab ozogamicin, alemtuzumab, and ibritumomab tiuxetan--are available for clinical use. Rituximab is active against indolent lymphomas, providing a valuable alternative for patients with relapsed or refractory disease. Rituximab plus cyclophosphamide-doxorubicin-vincristine-prednisone (CHOP) increased survival over CHOP alone in patients with high-grade lymphomas. Trastuzumab has significant activity against HER-2-positive breast cancer, especially in combination with paclitaxel or an anthracycline and cyclophosphamide. Gemtuzumab ozogamicin is an active second-line therapy in older patients with acute myelogenous leukemia, but its role in combination regimens is unclear. Alemtuzumab is a valuable option for salvage therapy of patients with chronic lymphocytic leukemia. Ibritumomab tiuxetan delivers radioactive isotopes to tumor cells and is active against indolent lymphomas in patients who have relapsed after chemotherapy or rituximab therapy. The most common adverse effects of monoclonal antibodies are myelosuppression, infusion-related reactions, and hypersensitivity reactions. Rituximab may cause tumor lysis syndrome, arrhythmias, and pulmonary dysfunction. Alemtuzumab causes immunosuppression, increasing the risk of infection. Gemtuzumab ozogamicin may cause hepatotoxicity, and trastuzumab may cause significant pulmonary or cardiac toxicity. Investigational monoclonal antibodies include edrecolomab and tositumomab. Monoclonal antibodies have a significant role in the management of patients with advanced refractory or relapsed lymphomas and leukemias.
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PMID:Monoclonal antibodies in the treatment of cancer, Part 1. 1295 53

Among the monoclonal antibodies (mAbs) under clinical development, anti-CD20 mAbs have been most extensively investigated and have shown definitive clinical activities. Rituximab is a genetically engineered, chimeric anti-CD20 mAb with mouse variable and human constant regions. Consecutive clinical trials conducted in the United States, Europe, and Japan have revealed that rituximab is an effective agent, with acceptable toxicities, in the treatment of indolent and aggressive B-cell non-Hodgkin's lymphomas (B-NHLs). A recent European phase III study in elderly patients with untreated diffuse large B-cell lymphoma suggested that rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) chemotherapy is superior to CHOP chemotherapy alone in terms of complete response rate and event-free and overall survivals. Lymphoma is inherently a radiosensitive tumor. The aim of radioimmunotherapy is to use the mAb to target radiation to lymphoma tissue while minimizing toxicity to normal cells. Clinical trials of (90)Y-ibritumomab tiuxetan and (131)I-tositumomab showed that they have definitive efficacy in relapsed indolent B-NHL, with acceptable toxicities. A recent comparative study in relapsed indolent B-NHL showed that (90)Y-ibritumomab tiuxetan produced a higher response rate than rituximab. In addition, BL22, a recombinant anti-CD22 immunotoxin, showed significant efficacy in patients with chemotherapy-resistant hairy cell leukemia. Monoclonal antibodies will have significant roles in the treatment of lymphoid malignancies in the future.
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PMID:Rituximab and other emerging antibodies as molecular target-based therapy of lymphoma. 1295 76

Monoclonal antibodies used in the treatment of cancer are discussed. Monoclonal antibodies are a new class of agents targeted at specific receptors on cancer cells. In addition to having direct cellular effects, antibodies can carry substances, such as radioactive isotopes, toxins, and antineoplastic agents, to the targeted cells. Five monoclonal antibodies--rituximab, trastuzumab, gemtuzumab ozogamicin, alemtuzumab, and ibritumomab tiuxetan--are available for clinical use. Rituximab is active against indolent lymphomas, providing a valuable alternative for patients with relapsed or refractory disease. Rituximab plus cyclophosphamide-doxorubicin-vincristine-prednisone (CHOP) increased survival over CHOP alone in patients with high-grade lymphomas. Trastuzumab has significant activity against HER-2-positive breast cancer, especially in combination with paclitaxel or an anthracycline and cyclophosphamide. Gemtuzumab ozogamicin is an active second-line therapy in older patients with acute myelogenous leukemia, but its role in combination regimens is unclear. Alemtuzumab is a valuable option for salvage therapy of patients with chronic lymphocytic leukemia. Ibritumomab tiuxetan delivers radioactive isotopes to tumor cells and is active against indolent lymphomas in patients who have relapsed after chemotherapy or rituximab therapy. The most common adverse effects of monoclonal antibodies are myelosuppression, infusion-related reactions, and hypersensitivity reactions. Rituximab may cause tumor lysis syndrome, arrhythmias, and pulmonary dysfunction. Alemtuzumab causes immunosuppression, increasing the risk of infection. Gemtuzumab ozogamicin may cause hepatotoxicity, and trastuzumab may cause significant pulmonary or cardiac toxicity. Investigational monoclonal antibodies include edrecolomab and tositumomab. Monoclonal antibodies have a significant role in the management of patients with advanced refractory or relapsed lymphomas and leukemias.
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PMID:Monoclonal antibodies in the treatment of cancer, Part 2. 1296 6


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