title: Sequence of administration and methylation of SOCS3 may govern response to gemtuzumab ozogamicin in combination with conventional chemotherapy in patients with refractory or relapsed acute myelogenous leukemia (AML).
abstract: In older patients suffering from acute myelogenous leukemia (AML), aggressive chemotherapy is accompanied with high treatment-related morbidity and mortality. Gemtuzumab ozogamicin (GO), a humanized monoclonal anti-CD33 antibody, represents a well tolerated treatment option, but optimal treatment schedules are still unknown. Additionally, Suppressor of cytokine signaling 3 (SOCS3) inhibits the CD33-induced block on cytokine-induced proliferation. Consequently, a variable response of AML cells to anti-CD33-targeted therapy may be caused by modulation of SOCS3 expression. Twenty-four patients with refractory or relapsed CD33-positive AML received GO as a single agent before or after conventional chemotherapy. The methylation status of the SOCS3 CpG island was assessed by methylation-specific polymerase chain reaction. Response (RR) and overall survival (OS) were significantly higher in 16 patients receiving chemotherapy before GO (RR 81%, OS 14.8 months) compared to three patients who received GO single agent therapy (RR 33%, OS 7.2 months) or 16 with GO before chemotherapy (RR 0% OS 2.2 months, P = 0.01 for RR and P < 0.001 for OS). Methylation of the SOCS3 CpG island was found in 8/24 patients. There was a trend towards a higher RR and longer OS in patients with SOCS3 hypermethylation (RR 86%, OS 25.1 months) compared to unmethylated SOCS3 (RR 56%, OS 10.3 months, P = 0.09). Administration of GO a few days after chemotherapy seems to provide better response and survival compared to administration of GO directly before chemotherapy. The potential role of SOCS3 hypermethylation as a biomarker should be further investigated in patients undergoing GO containing therapies.
authors.affiliation: Medizinische Klinik IV, Universitaetsklinikum Aachen, RWTH Aachen, Pauwelsstrasse 30, Aachen, Germany.
authors.forename: Iris
authors.initials: I
authors.lastname: Middeldorf
authors.forename: Oliver
authors.initials: O
authors.lastname: Galm
authors.forename: Rainhardt
authors.initials: R
authors.lastname: Osieka
authors.forename: Edgar
authors.initials: E
authors.lastname: Jost
authors.forename: James G
authors.initials: JG
authors.lastname: Herman
authors.forename: Stefan
authors.initials: S
authors.lastname: Wilop
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000617:Aminoglycosides / Q000008:administration & dosage* / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage; D018899:CpG Islands; D019175:DNA Methylation; D004334:Drug Administration Schedule; D000079982:Gemtuzumab; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy* / Q000401:mortality; D008875:Middle Aged; D012189:Retrospective Studies; D016879:Salvage Therapy / Q000379:methods*; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000235:genetics*; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D000617:Aminoglycosides; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; C106644:SOCS3 protein, human; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D000079982:Gemtuzumab