homoharringtonine and Colorectal-Neoplasms

Twenty-four previously untreated, ambulatory patients with advanced colorectal carcinoma were treated with either caracemide (11 patients) or homoharringtonine (13 patients). No objective responses were observed in any of the treatment cohorts. Caracemide was well tolerated with the exception of one death due to sepsis. On the homoharringtonine arm one patient died of pulmonary sepsis, one patient experienced grade 4 leukopenia requiring more than 4 weeks of recovery, and an additional patient developed grade 4 renal failure. These severe and unexpected complications caused early termination of accrual to the homoharringtonine arm of the study. These agents have no activity in the treatment of advanced colorectal carcinoma.

Topics: Adult; Aged; Antineoplastic Agents; Cohort Studies; Colorectal Neoplasms; Female; Harringtonines; Homoharringtonine; Humans; Hydroxyurea; Male; Middle Aged; Neoplasm Staging

Colorectal cancer (CRC) is the most common primary malignancy. Recently, antineoplastic attributes of homoharringtonine (HHT) have attracted lots of attention. This study investigated the molecular target and underlying mechanism of HHT in the CRC process by using a cellular and animal models.. This study first detected the effects of HHT on the proliferation, cell cycle and apoptosis ability of CRC cells using CCK-8, Edu staining, flow cytometry and Western blotting assay. In vitro recovery experiment and in vivo tumorigenesis experiment were used to detect the targeted interaction between HHT and NKD1. After that, the downstream target and mechanism of action of HHT targeting NKD1 was determined using quantitative proteomics combined with co-immunoprecipitation/immunofluorescence assay.. HHT suppressed CRC cells proliferation by inducing cell cycle arrest and apoptosis in vitro and vivo. HHT inhibited NKD1 expression in a concentration and time dependent manner. NKD1 was overexpressed in CRC and its depletion enhanced the therapeutic sensitivity of HHT on CRC, which indicating that NKD1 plays an important role in the development of CRC as the drug delivery target of HHT. Furthermore, proteomic analysis revealed that PCM1 participated the process of NKD1-regulated cell proliferation and cell cycle. NKD1 interacted with PCM1 and promoted PCM1 degradation through the ubiquitin-proteasome pathway. The overexpression of PCM1 effectively reversed the inhibition of siNKD1 on cell cycle.. The present findings revealed that HHT blocked NKD1 expression to participate in inhibiting cell proliferation and inducing cell apoptosis, ultimately leading to obstruction of CRC development through NKD1/PCM1 dependent mechanism. Our research provide evidence for clinical application of NKD1-targeted therapy in improving HHT sensitivity for CRC treatment.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Homoharringtonine; Proteomics

Homoharringtonine (HHT), an Food and Drug Administration (FDA)-approved anti-leukemia drug, exerts anti-tumor activity in several solid tumors, including colorectal cancer (CRC). However, its mechanism of action in CRC progression has not been comprehensively elucidated. The drug-disease targets were obtained using publicly available databases. Protein-protein interaction (PPI) network, Gene ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were performed to reveal the core targets, biological processes and signaling pathways of HHT against CRC. Cell and animal experiments were performed to validate the inhibitory effects of HHT on CRC. A total of 98 overlapping target genes of HHT and CRC were predicted. Through PPI network and topology analysis, we screened out 23 hub genes. Enrichment assays showed 163 biological processes (BP), 18 cell components (CC), 35 molecular functions (MF), and 85 related pathways. Functionally, HHT inhibited CRC cell proliferation, cell cycle progression, colony formation, migration and invasion, and promoted apoptosis. HHT treatment resulted in the inactivation of PI3K/AKT/mTOR signaling in CRC cells. Moreover, activation of PI3K/AKT/mTOR signaling by 740Y-P abated the suppressive effects of HHT on cell malignant phenotypes. Furthermore, HHT repressed CRC tumor growth in nude mice. Our current study demonstrated that HHT repressed CRC progression at least partly by inactivating PI3K/AKT/mTOR signaling pathways, highlighting HHT as a potential therapeutic agent for CRC patients.

Topics: Animals; Apoptosis; Cell Line, Tumor; Cell Movement; Cell Proliferation; Colorectal Neoplasms; Disease Progression; Gene Ontology; Homoharringtonine; Humans; Male; Mice, Inbred BALB C; Mice, Nude; Models, Biological; Molecular Sequence Annotation; Neoplasm Invasiveness; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Signal Transduction; TOR Serine-Threonine Kinases

Objective To investigate the molecular mechanisms underlying the effect of homoharringtonine (HHT) on the proliferation and apoptosis in HT29 human colorectal tumor cells. Methods HT29 cells were treated by 0, 0.007812, 0.015625, 0.03125, 0.0625, 0.125, 0.25, 0.5, 1, 2, 4, 8 μg/mL HHT for 24, 48 and 72 hours. CCK-8 assay was used to assess the cell viability. Colony formation assay was performed to detect the cell proliferation ability. Flow cytometry was used to analyze cell apoptosis. Hoechst33258 fluorescent staining was used to observe the morphology of the cell nuclei. The real-time quantitative PCR was used to detect the mRNA expressions of BAX, Bcl2, caspase-3, caspase-9, mammalian target of rapamycin (mTOR), PI3K, pyruvate dehydrogenase kinase-1 (PDK1), protein kinase B (AKT), raptor, rictor. The protein levels of Bax, Bcl2, pro-caspase-3, cleaved caspase 3 (c-caspase-3), pro-caspase-9, cleaved caspase-9 (c-caspase- 9), poly(ADP-ribose)polymerase (PARP), cleaved PARP (c-PARP), mTOR, raptor, rictor, PI3K, PDK1, AKT, p-AKT were detected by Western blotting. Results Compared with the control group, the proliferation of HT29 cells was inhibited when treated with HHT. Meanwhile, the nuclear fragmentation, chromatin condensation, and apoptotic body of the cells could be observed. Treatment of HHT could increase the mRNA expressions of BAX/Bcl2, caspase-3, caspase-9 and raptor, and decrease PI3K, AKT and rictor in the HT29 cells. The protein levels of pro-caspase-3, pro-caspase-9, PARP, PI3K, PDK1, AKT, mTOR, and rictor were down-regulated, and the c-caspase-3, c-caspase-9, c-PARP, BAX and raptor were up-regulated. Conclusion HHT has the function of inhibiting the HT29 cell proliferation and inducing its apoptosis by blockage of mTOR signaling pathway.

Topics: Apoptosis; Cell Proliferation; Colorectal Neoplasms; Homoharringtonine; HT29 Cells; Humans; Phosphatidylinositol 3-Kinases; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases