Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0854467 (myelosuppression)
 5,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

M195, a mouse monoclonal antibody reactive with the early myeloid antigen CD33, has been shown to target leukemia cells in patients and to reduce large leukemic burdens when labeled with 131I. A complementarity-determining region-grafted, humanized version (HuM195) has demonstrated similar targeting of leukemia cells without immunogenicity. We have studied two applications of therapy with 131I-M195. First, to intensify therapy prior to bone marrow transplantation (BMT), we combined 131I-M195 with busulfan and cyclophosphamide. Fifteen patients received first BMT for relapsed or refractory acute myelogenous leukemia or accelerated or blastic chronic myelogenous leukemia; four received second BMT for relapsed chronic or accelerated chronic myelogenous leukemia. Doses of 131I-M195 ranged from 120 to 230 mCi/m2. Few toxicities could be attributed to 131I-M195 therapy, and all patients engrafted. Eighteen patients achieved complete remission. Among those patients receiving first BMT, three have remained in unmaintained remission for 18+ to 29+ months. Six patients relapsed, including one with isolated central nervous system disease 32 months after BMT. Ten patients died in complete remission of transplant-related complications. Second, we studied whether 131I-M195 could reduce minimal residual disease and prolong remission and survival durations safely in patients with relapsed acute promyelocytic leukemia after they attained remission with all-trans-retinoic acid. Seven patients were treated with either 50 or 70 mCi/m2 131I-M195. Toxicity was limited to myelosuppression. As a measure of minimal residual disease, we monitored PML/RAR-alpha mRNA by reverse transcription PCR. Six patients had positive reverse transcription PCR assays prior to receiving 131I-M195; two converted transiently to negative. Median disease-free survival and overall survival of the seven patients were 8 (range, 3-14.5) months and 28 (range, 5.5-43+) months, respectively. This regimen compares favorably with others for relapsed acute promyelocytic leukemia. In an effort to avoid nonspecific cytotoxicity associated with 131I in future trials for minimal residual disease, we have conjugated short-range, alpha particle-emitting radioisotopes to HuM195 using a bifunctional chelate, 2-(p-isothiocyanatobenzyl)-cyclohexyldiethyl-enetriaminep entaacetic acid, with high efficiency and specific activities. 212Bi-HuM195 has demonstrated dose- and specific activity-dependent killing of HL60 cells in vitro. Injection of 213Bi-HuM195 into healthy BALB/c mice produced no effects on weight or viability.
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PMID:Radiolabeled anti-CD33 monoclonal antibody M195 for myeloid leukemias. 749 68

Tumour cells from a patient with recurrent testicular germ cell cancer and bone marrow infiltration were found to express CD33 and CD34 in the absence of other haemopoiesis-associated antigens. After myelosuppression and treatment with G-CSF for stem cell mobilization, CD34-positive tumour cells were detected in the peripheral blood in addition to normal haemopoietic progenitor cells. The tumour cells were decreased in the leukapheresis product. Retrospectively, the appearance of tumour cells in the peripheral blood after stem cell mobilization was the first indication of impending relapse.
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PMID:Mobilization of CD34-positive tumour cells in a patient with testicular mixed germ cell tumour. 754 27

A 67-year-old woman was treated with MP-P therapy and combination chemotherapy for multiple myeloma IgG-lambda type. After the therapy for about three years, pancytopenia developed. Bone marrow aspiration study revealed a few of myeloma cell and many atypical cells showing promyelocytic feature. Chromosomal abnormality was 46, X, -X, +8, -13, +mar. CD33 and CD56 were positive, but CD16 and HLA-DR were negative. We diagnosed as multiple myeloma complicated with secondary myeloid/natural killer (NK) cell acute leukemia. After she had been treated with low dose etoposide for leukemia, she obtained complete remission. But since myeloma progressed and the amount of M protein was increased, she was treated with dexamethasone and low dose etoposide, resulting in a decrease in the amount of M protein. After that, because of leukemic cell re-proliferation, she was treated with etoposide. However, she died of sepsis due to severe myelosuppression. This case was interesting one in coexist of multiple myeloma and secondary myeloid/NK cell acute leukemia, and those affecting her clinical course each other.
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PMID:[Secondary myeloid/natural killer cell acute leukemia appeared in multiple myeloma treated with melphalan]. 756 97

Acute promyelocytic leukemia (APL) provides a model to examine the sequential use of selective oncogene product-targeted and lineage-targeted agents. All-trans retinoic acid (RA) has been shown to produce brief remissions by a novel differentiating mechanism in most patients with APL. M195, a mouse monoclonal antibody (moAb) reactive with the cell-surface antigen CD33, can target myeloid leukemia cells in patients and reduce large leukemic burdens when labeled with 131I. We studied whether 131I-M195 could safely reduce minimal residual disease and prolong remission and survival durations in patients with relapsed APL after they had attained remission with all-trans RA. Seven patients with relapsed APL in second remission were treated with either 70 (n = 2) or 50 (n = 5) mCi/m2 of 131I-M195. As a measure of minimal residual disease, we serially monitored PML/RAR-alpha mRNA by a reverse transcription polymerase chain reaction (RT-PCR) assay. There was no immediate toxicity. Late toxicity was limited to myelosuppression, but no episodes of febrile neutropenia were seen. Six patients had detectable PML/RAR-alpha mRNA after all-trans RA therapy; two had single negative RT-PCR determinations following 131I-M195. Median disease-free survival of the seven patients was 8 months (range 3-14.5). Four patients with median follow-up of 24 months remain alive, and median overall survival exceeds 21+ months (range 5.5-33+). This regimen based on targeted therapy compares favorably to other approaches for the treatment of relapsed APL, including that used in the immediately preceding trial in which patients were induced into remission and maintained with all-trans RA, as well as other chemotherapy-based regimens. These data support further study of moAb-based therapy for minimal residual disease in acute leukemia.
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PMID:Sequential targeted therapy for relapsed acute promyelocytic leukemia with all-trans retinoic acid and anti-CD33 monoclonal antibody M195. 786 59

In December 1993, a 76-year-old Japanese male presented with general fatigue. Peripheral blood (PB) examination indicated marked leukocytosis (WBC count, 19.8 x 10(4)/microliter; leukemic blast differential, 89.5%). Leukemic blasts were positive for CD33, and negative for lymphoid antigens, with 2% of the blasts being positive for myeloperoxidase staining. On admission, chromosome analysis of leukemic cells in PB showed 45, X,-Y, t (9;22) [12/15]/46, XY, t (9;22) [3/15]. Southern blot analysis of the DNA from PB showed a rearrangement at the M-BCR region and germline configurations of both TCR beta and IgH chain genes. The patient was diagnosed as Philadelphia-positive chronic myelogenous leukemia (CML) in blast crisis. We commenced treatment with daunorubicin (DNR; 20 mg/day x 1 IV) and daily prednisolone (PSL; 60 mg/day PO). Leukemic blasts disappeared rapidly from PB, while the promyelocytes showed a transient increase, peaked 7 days after the start of therapy, and then disappeared. Myelocytes and metamyelocytes also showed transient increases. Without a period of severe myelosuppression, the patient reverted to the chronic phase of CML and karyotypic analysis of bone marrow cells showed 45, X,-Y, t (9;22) [33/35]/46, XY, [2/35]. Consolidation chemotherapy with DNR and BHAC was started, but the patient's condition deteriorated due to bacterial infection and he died of hepatic failure on March 1994. In this case, reversion to the chronic phase of CML in blast crisis may be accomplished by the cytodifferentiating effects of small-dose DNR and oral PSL to the leukemic blasts.
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PMID:[Reversion to chronic phase of chronic myelogenous leukemia in blast crisis with small-dose daunorubicin and oral prednisolone]. 858 71

Ad.CMV-CD is a replication incompetent adenoviral vector carrying a cytomegalovirus (CMV)-driven transcription unit of the cytosine deaminase (CD) gene. The CD transcription unit in this vector catalyzes the deamination of the nontoxic pro-drug, 5-fluorocytosine (5-FC), thus converting it to the cytotoxic drug 5-fluorouracil (5-FU). This adenoviral vector prodrug activation system has been proposed for use in selectively sensitizing breast cancer cells, which may contaminate collections of autologous stem cells products from breast cancer patients, to the toxic effects of 5-FC, without damaging the reconstitutive capability of the normal hematopoietic cells. This system could conceivably kill even the nondividing breast cancer cells, because the levels of 5-FU generated by this system are 10 to 30 times that associated with systemic administration of 5-FU. The incorporation of 5-FU into mRNA at these high levels is sufficient to disrupt mRNA processing and protein synthesis so that even nondividing cells die of protein starvation. To test if the CD adenoviral vector sensitizes breast cancer cells to 5-FC, we exposed primary explants of normal human mammary epithelial cells (HMECs) and the established breast cancer cell (BCC) lines MCF-7 and MDA-MB-453 to the Ad.CMV-CD for 90 minutes. This produced a 100-fold sensitization of these epithelial cells to the effects of 48 hours of exposure to 5-FC. We next tested the selectivity of this system for BCC. When peripheral blood mononuclear cells (PBMCs), collected from cancer patients during the recovery phase from conventional dose chemotherapy-induced myelosuppression, were exposed to the Ad.CMV-CD for 90 minutes in serum-free conditions, little or no detectable conversion of 5-FC into 5-FU was seen even after 48 hours of exposure to high doses of 5-FC. In contrast, 70% of 5-FC was converted into the cytotoxic agent 5-FU when MCF-7 breast cancer cells (BCCs) were exposed to the same Ad.CMV-CD vector followed by 5-FC for 48 hours. All of the BCC lines tested were shown to be sensitive to infection by adenoviral vectors when exposed to a recombinant adenoviral vector containing the reporter gene betagalactosidase (Ad.CMV-betagal). In contrast, less than 1% of the CD34-selected cells and their more immature subsets, such as the CD34+CD38- or CD34(+)CD33- subpopulations, were positive for infection by the Ad.CMV-betagal vector, as judged by fluorescence-activated cell sorting (FACS) analysis, when exposed to the adenoviral vector under conditions that did not commit the early hematopoietic precursor cells to maturation. When artificial mixtures of hematopoietic cells and BCCs were exposed for 90 minutes to the Ad.CMV-CD vector and to 5-FC for 10 days or more, a greater than 1 million fold reduction in the number of BCCs, as measured by colony-limiting dilution assays, was observed. To test if the conditions were damaging for the hematopoietic reconstituting cells, marrow cells collected from 5-FU-treated male donor mice were incubated with the cytosine deaminase adenoviral vector and then exposed to 5-FC either for 4 days in vitro before transplantation or for 14 days immediately after transplantation in vivo. There was no significant decrease in the reconstituting capability of the male marrow cells, as measured by their persistence in female irradiated recipients for up to 6 months after transplantation. These observations suggest that adenovirus-mediated gene transfer of the Escherichia coli cytosine deaminase gene followed by exposure to the nontoxic pro-drug 5-FC may be a potential strategy to selectively reduce the level of contaminating BCCs in collections of hematopoietic cells used for autografts in breast cancer patients.
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PMID:Cytosine deaminase adenoviral vector and 5-fluorocytosine selectively reduce breast cancer cells 1 million-fold when they contaminate hematopoietic cells: a potential purging method for autologous transplantation. 965 70

The antigen CD33 is expressed on blast cells in 80% to 90% of acute myeloid leukemia (AML) cases but, importantly, is not expressed on pluripotent hematopoietic stem cells or on nonhematologic cells. Gemtuzumab ozogamicin (CMA-676) uses a recombinant humanized anti-CD33 monoclonal IgG4 antibody to deliver the potent cytotoxin, calicheamicin, into cells. Three multicenter trials have evaluated the efficacy and safety of gemtuzumab ozogamicin as a single agent in 142 patients with CD33+ AML in untreated first relapse. The median age was 61 years (range, 22 to 84 years), none had prior myelodysplasia, and all had had a first complete remission lasting > or = 3 months. Two doses of 9 mg/m2 were given 14 days apart by 2-hour intravenous infusion. The overall response rate was 30% (ie, < or = 5% blasts remaining in the bone marrow, neutrophils > or = 1,500/microL, and red blood cell and platelet transfusion independence). There was no significant difference in response rate between patients less than 60 years of age and those > or = 60 years old (34% v 26%, respectively) or between patients whose first remission had lasted less than 12 months or > or = 12 months (28% v 32%, respectively). Overall survival was 31% at 1 year; median survival was 5.9 months. Median relapse-free survival was 6.8 months. An infusion-related syndrome (chills, fever, rigors, nausea, hypotension, and pain) was common. Severe myelosuppression occurred in all patients, but severe mucositis (4%) and infections (23%) were relatively infrequent. Severe hyperbilirubinemia (23%) and elevated hepatic transaminases (18%) were usually transient. Among all 142 patients, the median total hospitalization was 24 days; 16% of patients required < or = 7 days in hospital. Additional studies are currently evaluating gemtuzumab ozogamicin in combination with, or as an alternative to, other standard AML chemotherapy.
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PMID:Current use and future development of gemtuzumab ozogamicin. 1147 94

Gemtuzumab ozogamicin is a humanised monoclonal IgG4 antibody, linked to a cytotoxic calicheamicin derivative. It effects cell necrosis by specifically targeting the CD33 antigen which is expressed on the surface of leukaemic cell blasts in more than 90% of patients with acute myeloid leukaemia (AML), but is not present on normal stem cells. Therapy with gemtuzumab ozogamicin (2 doses of 9 mg/m2) in 3 noncomparative studies produced complete remission in 16% of adult patients with AML in first relapse, and complete remission with incomplete platelet recovery in an additional 13% of patients. Rates of remission did not differ between those aged less than 60 years and older than 60 years. Many patients were able to receive both doses of gemtuzumab ozogamicin therapy as outpatients. Survival duration was similar between those treated as outpatients and those requiring hospitalisation. About one-third of 11 children and adolescents treated with 2 doses of 9 mg/m2 gemtuzumab ozogamicin in a phase I study showed <5% bone marrow blasts after completion of therapy. The most commonly encountered adverse events in clinical trials with gemtuzumab ozogamicin were myelosuppression, increased levels of hepatic enzymes, infection, fever, bleeding, chills, nausea and vomiting and dyspnoea. No treatment-related renal failure or alopecia was reported.
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PMID:Gemtuzumab ozogamicin. 1151 Oct 25

Mylotarg (gemtuzumab ozogamicin, CMA-676; Wyeth-Ayerst Laboratories, Philadelphia, PA) recently was approved by the US Food and Drug Administration for the treatment of patients with CD33-positive acute myeloid leukemia in first relapse, age 60 years or older, who are not considered candidates for other types of cytotoxic chemotherapy. In combined phase II studies of 142 patients with CD33-positive acute myeloid leukemia in first relapse, Mylotarg monotherapy was associated with a 30% overall response rate. Although treated patients had relatively high incidences of myelosuppression, hyperbilirubinemia, and elevated hepatic transaminases, the incidences of severe mucositis and infections were low compared with what might be expected in association with conventional chemotherapeutic treatment. Preliminary data in pediatric patients also suggest that the immunoconjugate is reasonably well tolerated. Studies of Mylotarg in combination with anthracycline, cytarabine, and agents that inhibit P-glycoprotein are underway.
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PMID:Mylotarg: antibody-targeted chemotherapy comes of age. 1167 94

Although DNA repair processes have been shown to considerably modulate the cytotoxic effects of alkylating agents, little information is available on the role of these mechanisms in chemotherapy-induced myelosuppression. Therefore, we have analyzed in detail the DNA repair capacity of primary human hematopoietic cells from cord blood (CB) or bone marrow (BM) by 2 functional assays, the immunocytologic assay (ICA) and single-cell gel electrophoresis (comet assay). Besides substantial interindividual differences, we consistently observed significantly lower repair capacity of CD34(+) cells in comparison to CD34(-), CD19(+), or CD33(+) cells of the same donor. After exposure to the alkylating agent ethylnitrosourea (EtNU), the comet assay displayed on average twice as many DNA single-strand breaks (SSBs) in CD34(+) cells and a tripled half-life of these lesions in comparison to corresponding CD34(-) cells. Similarly, reduced SSB repair activity in CD34(+) cells was detected following melphalan or cisplatin application. When specific antibodies were used to monitor DNA reaction products of these drugs, adduct levels were significantly higher and lesions persisted longer in the CD34(+) fraction. To assess the contribution of individual pathways to overall DNA repair, modulators blocking defined steps in repair processes were coapplied with alkylating drugs. Similar "modulation pattern" in corresponding CD34(+) and CD34(-) cell fractions indicated a generalized reduction in DNA repair capacity of CD34(+) cells, rather than deficiencies in a specific pathway. Because CD34(+) cells also displayed higher frequencies of apoptosis in response to melphalan or cisplatin, these findings may help to explain the myelosuppression after exposure to alkylating agents.
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PMID:Down-regulation of DNA repair in human CD34(+) progenitor cells corresponds to increased drug sensitivity and apoptotic response. 1213 Apr 94


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