ABSTRACT
AIMS: To functionally express the recombinant mouse insulin-like growth factor-I (rtmIGF-I) in Lactococcus lactis NZ9000 with a food-grade vector. METHODS AND RESULTS: The rtmIGF-I encoding sequence was inserted into secreted food-grade vector pLEB688 and transformed into L. lactis NZ9000. The expression of the recombinant protein rtmIGF-I was confirmed by tricine-SDS-PAGE analysis and Western blot. The concentration of this recombinant protein was 3 mg l(-1) in the medium fraction. Further experiment demonstrated that the recombinant protein was biologically active and promoted NIH3T3 cell proliferation in a concentration-dependent manner. CONCLUSIONS: The rtmIGF-I was expressed in L. lactis and located into the medium fraction. The optimal final concentration which could promote NIH3T3 cell proliferation after incubation was 100 ng ml(-1) . SIGNIFICANCE AND IMPACT OF THE STUDY: The rtmIGF-I was functionally expressed in L. lactis NZ9000 with a food-grade vector. Thus, the recombinant L. lactis NZ9000 could act as a host for the production of rtmIGF-I for further study. The recombinant strain could serve as an IGF-I delivery system.
Subject(s)
Insulin-Like Growth Factor I/metabolism , Lactococcus lactis/metabolism , Animals , Blotting, Western , Electrophoresis, Polyacrylamide Gel , Genetic Vectors , Insulin-Like Growth Factor I/genetics , Lactococcus lactis/genetics , Lactococcus lactis/growth & development , Mice , NIH 3T3 Cells , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Somatomedins/genetics , Somatomedins/metabolismABSTRACT
To assess the efficacy and toxicity of HAA regimen (homoharritonine 4 mg/m2/day, days 1-3; cytarabine 150 mg/m2/day, days 1-7; aclarubicin 12 mg/m2/day, days 1-7) as an induction therapy in the treatment of de novo acute myeloid leukemia (AML), 48 patients with newly diagnosed AML, aged 35 (14-57) years, were entered into this clinical study. The median follow-up was 26 months. Eighty-three percent of patients achieved complete remission (CR), and the first single course of induction HAA regimen resulted in CR rate of 79%. The CR rate of 100, 82 and 33% were achieved in patients with favorable, intermediate and unfavorable cytogenetics, respectively. For all patients who achieved CR, the median time from the initiation of the induction therapy to the evaluation of the remission status was 32 days. For all patients, the estimated 3 years overall survival (OS) rate was 53%, whereas for patients with M5, the estimated OS rate at 3 years was 75%. The toxicities associated with HAA regimen were acceptable, and the most common toxicity was infection. This study suggested that HAA regimen might be a well-tolerable, effective induction regimen in young adult patients with AML.