SLXM-2, a derivative of cyclophosphamide: mechanism of growth inhibition on hepatocarcinoma 22 cells.
Restructuring of cyclophosphamide (CPA) is a promising method for the development of antineoplastic therapy. This study investigated the inhibitory effects of a derivative of CPA, SLXM-2, on hepatocarcinoma 22 (H22) transplanted into ICR mice as well as its effects on the survival time of mice transplanted with the ascitic fluid-type H22. We found that SLXM-2 inhibited tumor growth and prolonged survival time. Moreover, the compound had little effect in vivo on leukocytes and body weight and a higher lethal dose 50 than CPA. The cell cycle analysis by flow cytometry revealed that SLXM-2 arrested tumor cells in both the S and G2 phases, and the arrest in the G2 phase increased in a dose-dependent manner. Western blotting and reverse transcription-PCR experiments indicated that the observed G2 arrest was associated with an increase of cyclin B1, whereas cell division cycle protein 2 (Cdc2) remained constant. The results, however, showed an accumulation of tyrosine 15 phosphorylated Cdc2 and a reduction of threonine 161 phosphorylated Cdc2. In addition, SLXM-2 led to a decrease in cyclin-dependent kinase 7 and Cdc25c kinase, which participated in inhibiting the G2/M transition. Our data identified two upstream targets leading to the inactivity of the cyclin B1/Cdc2 complex, which explained the arrest in the G2/M phase following SLXM-2 treatment. These results demonstrated the antitumor activity of SLXM-2 and its potential use as an antineoplastic drug.
Pang
Li-ping
LP
National Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, China.
Huang
Wei
W
Sun
Qi
Q
Guo
Wei
W
Li
Run-tao
RT
Cui
Jing-rong
JR
D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000008:administration & dosage / Q000737:chemistry / Q000627:therapeutic use; D015153:Blotting, Western; D042846:CDC2-CDC28 Kinases / Q000235:genetics / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D019926:Cyclin B / Q000235:genetics / Q000378:metabolism; D056744:Cyclin B1; D003520:Cyclophosphamide / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D016195:G2 Phase / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects; D007274:Injections, Intraperitoneal; D007958:Leukocyte Count; D008114:Liver Neoplasms, Experimental / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D015394:Molecular Structure; D010879:Piperazines / Q000008:administration & dosage / Q000737:chemistry / Q000627:therapeutic use*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016196:S Phase / Q000187:drug effects; D015431:Weight Loss / Q000187:drug effects
C527793:3-methyl-9-(2-oxa-2lambda(5)-2H-1,3,2-oxazaphosphorine-2-cyclohexyl)-3,6,9-triazaspiro(5.5)undecane; D018906:Antineoplastic Agents, Alkylating; C534700:Ccnb1 protein, mouse; D019926:Cyclin B; D056744:Cyclin B1; D010879:Piperazines; D012333:RNA, Messenger; D003520:Cyclophosphamide; D042846:CDC2-CDC28 Kinases