Project description:Microarray analysis revealed differential gene expression patterns of HT1080 cells treated with various chemical compounds alone and in combination (trabectedin, doxorubicin, mafosfamide, TRAIL, taurolidine) Microarray analysis of HT1080 cells treated with various chemical compounds alone and in combination (trabectedin, doxorubicin, mafosfamide, TRAIL, taurolidine)
Project description:Microarray analysis revealed differential gene expression patterns of HT1080 cells treated with various chemical compounds alone and in combination (trabectedin, doxorubicin, mafosfamide, TRAIL, taurolidine)
Project description:Desmoplastic small round cell tumor (DSRCT) is a rare and incurable malignancy characterized by the oncogenic EWSR1-WT1 transcription factor. This study exploited a novel DSRCT patient-derived xenograft (PDX), which reproduces histomorphological and molecular characteristics of the paired clinical tumor, to comparatively assess the activity of cytotoxic and targeted anticancer agents. Anti-tumor effect was moderate for single-agent doxorubicin, pazopanib and larotrectenib [maximum tumor volume inhibition (max TVI): 55-66%] while trabectedin had a higher effect (max TVI: 82%). Single-agent vinorelbine, irinotecan and eribulin achieved a nearly complete tumor growth inhibition (max TVI: 96-98%), although tumors started to re-growth after the end of treatment. Combination of irinotecan with either eribulin or trabectedin resulted in complete responses which were maintained until the end of the experiment for irinotecan plus trabectedin. Irinotecan-based combinations almost completely abrogated the expression of proteins involved in the G2/M checkpoint preventing cell entrance in mitosis and induced apoptotic and necroptotic cell death. This study emphasizes the importance of patient-derived pre-clinical models to explore new treatments in DSRCT and fosters clinical investigation in the activity of irinotecan plus trabectedin.
Project description:Desmoplastic small round cell tumor (DSRCT) is a rare and incurable malignancy characterized by the oncogenic EWSR1-WT1 transcription factor. This study exploited a novel DSRCT patient-derived xenograft (PDX), which reproduces histomorphological and molecular characteristics of the paired clinical tumor, to comparatively assess the activity of cytotoxic and targeted anticancer agents. Anti-tumor effect was moderate for single-agent doxorubicin, pazopanib and larotrectenib [maximum tumor volume inhibition (max TVI): 55-66%] while trabectedin had a higher effect (max TVI: 82%). Single-agent vinorelbine, irinotecan and eribulin achieved a nearly complete tumor growth inhibition (max TVI: 96-98%), although tumors started to re-growth after the end of treatment. Combination of irinotecan with either eribulin or trabectedin resulted in complete responses which were maintained until the end of the experiment for irinotecan plus trabectedin. Irinotecan-based combinations almost completely abrogated the expression of proteins involved in the G2/M checkpoint preventing cell entrance in mitosis and induced apoptotic and necroptotic cell death. This study emphasizes the importance of patient-derived pre-clinical models to explore new treatments in DSRCT and fosters clinical investigation in the activity of irinotecan plus trabectedin.
Project description:A major limitation in the cancer treatment is the ability of cancer cells to become resistant to chemotherapeutic drugs, by multidrug establishment. Here, we evaluate the possibility to utilize MC70, either as ABC transporters inhibitor or as anticancer agent, in monotherapy or in combination with doxorubicin for cancer treatment. The study was carried out in MCF7/ADR and Caco-2, breast and colon cancer cells, respectively. Cell growth and apoptosis were measured by MTT assay and DNA laddering Elisa kit, respectively. Cell cycle perturbation and cellular targets modulation were analyzed by flow cytometry and western blotting, respectively. MC70 was analyzed for its interaction with ABC transporters, MDR-1, BCRP and MRP-1, and for its anticancer activity. In MCF7/ADR, MC70 slight inhibited cell proliferation and strongly enhanced doxorubicin effectiveness; conversely in Caco-2, it inhibited cell growth without affecting doxorubicin efficacy. In addition, it induced apoptosis, canceled in favor of necrosis when it was given in combination with high doses of the anthracycline. Moreover, MC70 inhibited cell migration probably through its residual activity as sigma-1 ligand. Among the hypothesized molecular and cellular mechanisms responsible for all these effects, modulations of cell cycle, of pAkt and of the three MAPKs phosphorylation were evidenced while activity at transcription level was excluded. MC70 can be considered as a potential new anticancer agent with the capability to enhance doxorubicin effectiveness and an interesting role in the treatment of chemotherapy resistant tumors. The study included the basic characterization of MC70 efficacy as inhibitor of MDR transporters, the investigation of its anticancer behavior and the exploration of the molecular and cellular mechanisms responsible for it
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising agent in selectively killing tumor cells. However, TRAIL monotherapy is not especially successful due to the fact that many cancer cells are resistant to TRAIL. Chemotherapeutic agents, such as doxorubicin have been shown to act synergistically with TRAIL on cancer cells, but the exact mechanisms of actions are poorly understood. In this study we performed high-throughput siRNA screening and genome-wide gene expression profiling on doxorubicin treated U1690 cells to explore novel mechanisms underlying doxorubicin-TRAIL synergy. The screening and expression profiling results were integrated and dihydroorotate dehydrogenase (DHODH) was identified to be a potential candidate. DHODH is rate-limiting enzyme in the pyrimidine synthesis pathway, and its expression was downregulated by doxorubicin and silencing of DHODH sensitized U1690 cells to TRAIL. Inhibition of DHODH activity by brequinar dramatically increased the sensitivity of U1690 cells to TRAIL-induced apoptosis, and was accompanied by downregulation of cFLIPL and mitochondrial depolarization. However, the expressions of DR4 and 5 were not changed in response to brequinar treatment in contrast to doxorubicin. In addition, uridine, an end product of the pyrimidine synthesis pathway was able to rescue the sensitization effects initialized by both brequinar and doxorubicin. Furthermore, other cancer cell lines, LNCaP, MCF-7 and HT-29 were also shown to be sensitized to TRAIL by brequinar. Taken together, our findings have identified a novel drug, brequinar, to be potentially utilized in TRAIL combinatorial cancer therapy and highlighted for the first time the importance of DHODH and pyrimidine pathway in mediating TRAIL sensitization in cancer cells. Total RNA obtained from small cell lung cancer U1690 cells either treated with DMSO control or 1 M-BM-5M doxorubicin for 12 or 24h.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.