OBJECTIVETo investigate apoptosis in vivo in patients with leukemia at different stages of the first cycle of chemotherapy.

METHODSWe detected apoptosis of HL-60 cells and peripheral blood leukemia cells in 17 patients at different stages, using in situ terminal deoxynucleotidyl transferase (TdT) fluorescence measurement and DNA electrophoresis.

RESULTSWhen HL-60 cells were incubated with 0.02 mg/L harringtonine for 0 to 48 hours, agarose gel electrophoresis showed that DNA ladder patterns became evident only at 12 hour into the treatment. In situ TdT assay showed that apoptotic cells occurred after one hour of the treatment. Apoptotic cells were few (0 - 3.3%) before chemotherapy, but increased substantially (11.4% - 87.5%) during chemotherapy in patients with complete remission (CR) or partial remission (PR). Apoptotic cells were few (0 - 6.1%) during chemotherapy in ten patients with no remission (NR). DNA ladder cannot be detected by agarose gel electrophoresis either before, during or after chemotherapy. Wilcoxon signed rank test shows: P = 0.0012 < 0.01, apoptotic cells during chemotherapy were present in greater quantity than prior to chemotherapy. Wilcoxon rank sum test shows: P = 0.0011 < 0.01, with the median of apoptotic cells during chemotherapy in patients with CR or PR more than with NR.

CONCLUSIONSTdT assay can be used to detect apoptotic cells earlier and more sensitively than DNA agarose gel electrophoresis. In situ TdT assay is useful to detect apoptosis in vivo in the initial phase of chemotherapy for immediate modification of the chemotherapy regimen, whereas electrophoretic analysis is not sensitive enough to detect apoptotic cell in vivo. Where the median of apoptotic cells during chemotherapy in patients with CR or PR were greater than with NR, only effective drug therapy could induce apoptosis.

Adult ; Aged ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; DNA Damage ; Female ; HL-60 Cells ; Humans ; Leukemia ; drug therapy ; pathology ; Male ; Middle Aged

Objective: To investigate the therapeutic effects of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with FLAG sequential busulfan/cyclophosphamide(Bu/Cy) conditioning regimen for refractory/relapsed acute myeloid leukemia. Methods: From February 2012 to June 2017, 21 patients with refractory/relapsed acute myeloid leukemia underwent allo-HSCT with FLAG sequential Bu/Cy conditioning regimen. Transplantation-related complications and clinical outcome were retrospectively analyzed. Results: After conditioning, no hepatic veno-occlusive disease (VOD) and grade Ⅲ hemorrhagic cystitis occurred. 76.2% (16/21) patients had fever with 4 septicemia. One patient died of septic shock before engraftment. Twenty patients achieved neutrophil engraftment with a median time of 13 days (range, 10 to 21 days). Seventeen patients achieved platelet engraftment with a median time of 18 days (range, 9 to 25 days). The cumulative incidence of acute graft-versus-host disease (aGVHD) was 39.5%, and 3 patients developed grade Ⅲ-Ⅳ aGVHD. Of 19 patients who survived more than 100 days after transplantation, 4 had local chronic graft-versus-host disease (cGVHD). Of 21 patients, the median survival time was 15 months (range, 0.5 to 67 months) post-transplantation. Transplantation-related mortality rate was 28.7%. Leukemia relapse occurred in 4 patients with a median time of 4 months (range, 3 to 8 months) after transplantation. The cumulative relapse rate at 1 year was 21.4%. The 1-year and 3-year overall survival (OS) rates were 60.7% and 54.9% respectively. Log-rank analysis revealed that bone marrow blasts ≥ 20% or extramedullary leukemia before transplantation, poor platelet engraftment and grade Ⅲ-Ⅳ aGVHD were significantly related to shortened OS (P<0.05). Conclusions Allo-HSCT with FLAG sequential Bu/Cy conditioning regimen in patients with refractory/relapsed myeloid leukemia has acceptable transplantation-related risk and relapse rate. The 1-year and 3-year OS rates are comparable with those in remission patients.