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  • 1
    Online Resource
    Online Resource
    Public Library of Science (PLoS) ; 2016
    In:  PLOS ONE Vol. 11, No. 9 ( 2016-9-29), p. e0163961-
    In: PLOS ONE, Public Library of Science (PLoS), Vol. 11, No. 9 ( 2016-9-29), p. e0163961-
    Type of Medium: Online Resource
    ISSN: 1932-6203
    Language: English
    Publisher: Public Library of Science (PLoS)
    Publication Date: 2016
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  • 2
    Online Resource
    Online Resource
    Impact Journals, LLC ; 2017
    In:  Oncotarget Vol. 8, No. 32 ( 2017-08-08), p. 53017-53027
    In: Oncotarget, Impact Journals, LLC, Vol. 8, No. 32 ( 2017-08-08), p. 53017-53027
    Type of Medium: Online Resource
    ISSN: 1949-2553
    URL: Issue
    Language: English
    Publisher: Impact Journals, LLC
    Publication Date: 2017
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  • 3
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2016
    In:  Cancer Research Vol. 76, No. 14_Supplement ( 2016-07-15), p. 4659-4659
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 76, No. 14_Supplement ( 2016-07-15), p. 4659-4659
    Abstract: Background: In colorectal cancer chemotherapy, the current standard of care includes 5-fluorouracil (5-FU) and leucovorin (LV) combination therapy. To understand the role of folic acid-metabolizing enzymes in the LV-mediated enhancement of 5-FU's antitumor activity, we suppressed the expression of genes related to folic acid metabolism and evaluated the resultant effect on the proliferation inhibitory effect of 5-fluoro-2′-deoxyuridine (FdUrd). Method: We downregulated the expression of thymidylate synthase (TS), folate receptor 1 (FOLR1), methylenetetrahydrofolate reductase (MTHFR), methylenetetrahydrofolate dehydrogenase (MTHFD), dihydrofolate reductase (DHFR), and phosphoribosylglycinamide formyltransferase (GART) by lipofection of small interfering RNA (siRNA) in DLD-1 and HCT116 cells, and calculated the relative change in IC50 values on 48 hr exposure to FdUrd in comparison with the corresponding IC50 values in control siRNA-treated cells. In cells with TS downregulation, LV-mediated enhancement of sensitivity to FdUrd was also evaluated. Sensitivity to FdUrd was determined using the crystal violet staining method. Results: Treatment with siRNA downregulated the expression of folic acid-metabolizing enzymes. LV enhanced the sensitivity to FdUrd in control siRNA-treated cells in a dose-dependent manner. However, in cells with TS downregulation, LV did not enhance the sensitivity to FdUrd. Downregulation of folic acid-metabolizing enzymes, except TS, decreased the efficacy of FdUrd, although there was little decrease in FdUrd efficacy owing to MTHFR downregulation. Conclusion: The level of TS expression determined the LV requirement, and downregulation of folic acid-metabolizing enzymes, which impaired the folic acid cycle, decreased the efficacy of 5-FU. Comparison of the IC50 values in target siRNA-treated cells and control siRNA-treated cells.DLD-1 cellsHCT116 cellsexpression (%)*IC50 (μM)fold changeexpression (%)*IC50 (μM)fold changeNon-silencing Control siRNA100.000.671.00100.000.251.00TS10.580.010.0114.840.030.12FOLR19.148.6512.9125.122.5910.36MTHFR25.441.432.1348.750.883.52MTHFD9.662.734.0715.061.997.96DHFR8.524.146.1817.231.706.80GART18.905.388.037.102.469.84Values are means (n = 3). *: Expression (%) is the expression at the beginning of FdUrd treatment (at 48 hr after siRNA treatment). Citation Format: Hiroshi Tsukihara, Kenta Tsunekuni, Teiji Takechi. Folic acid-metabolizing enzymes regulate 5-fluorouracil anticancer activity on colorectal cancer cell lines. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4659.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2016
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  • 4
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2019
    In:  Cancer Research Vol. 79, No. 13_Supplement ( 2019-07-01), p. 2963-2963
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 79, No. 13_Supplement ( 2019-07-01), p. 2963-2963
    Abstract: Background: Cancer stem cells (CSCs) are involved in disease recurrence, metastases, and therapeutic resistance. However, anticancer agents that target CSCs are not currently available. Trifluridine (FTD)/tipiracil (TPI), a novel oral antitumor drug, was approved for the treatment of patients with metastatic colorectal cancer who had been previously treated with anti-vascular endothelial growth factors; anti-epidermal growth factor receptors (in patients with ras wild-type genes); or fluoropyrimidine-, oxaliplatin-, irinotecan-based chemotherapies. FTD/TPI improves overall survival, and FTD is the key component of FTD/TPI. Here, we demonstrated the efficacy of FTD against CD44 and CD133 high-expressing (CD44+CD133+) colorectal cancer cells that possess CSC-like properties. Method: CD44+CD133+ and other populations of DLD-1, a colorectal cell line, were separated by fluorescence-activated cell sorting (FACS). The sphere-forming activity of each population, and anti- sphere-forming effects of FTD and fluorouracil (5-FU) on CD44+CD133+ cells, were measured. In addition, DLD-1 and HCT-116, two colorectal cell lines, were treated with FTD for 5 months. The CSC markers CD44 and CD133 were measured by FACS, and the cells' in vitro and in vivo tumor-initiating properties were evaluated. Results: CD44+CD133+ DLD-1 cells formed significantly more spheres than did CD44-CD133- cells (sphere ratio CD44+CD133+/CD44-CD133- = 4.0) and CD44+CD133- cells (sphere ratio CD44+CD133+/CD44+CD133- = 1.7). In the in vitro proliferation assay, CD44+CD133+ cells had greater 5-FU resistance, but not higher FTD resistance, than did unsorted cells. In addition, treatment of CD44+CD133+ DLD-1 cells with subtoxic concentrations of FTD (1 µM) disrupted sphere formation, which was superior to the effect of treatment with 1 µM 5-FU. The inhibition rates for FTD and 5-FU were 59.5% and 14.3%, respectively. DLD-1 and HCT-116 cell lines treated with FTD for 5 months had smaller CD44+CD133+ populations and lower sphere-forming activity than did untreated cell lines; population decline rates were 93.8% and 74.7%, respectively. Furthermore, 5 months of in vitro exposure to FTD reduced in vivo tumor formation potential in both cell lines. These results suggest that FTD is effective against CSC-like cells, and that treatment with FTD might reduce CSC-like populations. Conclusion: FTD had a direct effect on the sphere-forming activity of CSC-like CD44+CD133+ cells that was superior to that of treatment with 5-FU. Its effectiveness against CSC-like CD44+CD133+ cells suggests that FTD might be useful for CSC-targeted chemotherapy in tumors that highly express CD44 and CD133. Citation Format: Kenta Tsunekuni, Masamitsu Konno, Jun Koseki, Ayumu Asai, Kazuaki Matsuoka, Teiji Takechi, Yuichiro Doki, Masaki Mori, Hideshi Ishii. CD44+/CD133+ colorectal cancer stem cells are sensitive to trifluridine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2963.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2019
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  • 5
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2020
    In:  Cancer Research Vol. 80, No. 16_Supplement ( 2020-08-15), p. 5266-5266
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 80, No. 16_Supplement ( 2020-08-15), p. 5266-5266
    Abstract: Background: Trifluridine (FTD) is a key component of the novel, orally-administered, antitumor drug trifluridine/tipiracil, and is approved for treatment of patients with metastatic colorectal and gastric/GEJ cancers refractory to standard chemotherapy. FTD, an antineoplastic thymidine analogue, is incorporated into the genomic DNA of tumor cells, thereby triggering cell death. An international, double-blind, placebo-controlled Phase III study confirmed the efficacy of trifluridine/tipiracil in patients previously treated with standard chemotherapy. However, the clinical benefit of trifluridine/tipiracil in the first-line metastatic setting still remains unknown. Therefore, we analyzed the sensitivity for FTD, 5-FU, L-OHP, and SN-38 in parental and three FTD long-term treated cell lines. Methods: Three human colorectal cancer cell lines (DLD-1, HCT-116, and RKO) and their respective FTD long-term treated cell lines (treated by step-wise increase in concentrations of FTD starting at 1 µM and ending at 400 µM over a 5 month period) were used. Sensitivity assays using crystal violet staining for FTD, 5-FU, L-OHP, and SN-38 and wound healing assay to assess the migration capacity were performed in these cell lines. Further, mRNA was purified and the resulting microarray was utilized to analyze expression profiles. Results: Continuous FTD long-term treated cell lines were resistant to FTD. In the sensitivity assays, the IC50 values in all three continuously FTD treated cell lines increased by & gt;22-fold for FTD, by & lt;2-fold for 5-FU and L-OHP, and by & lt;9-fold for SN-38 (2 to 8.2-fold in three cell lines) compared to those in parental cell lines. We found that FTD long-treated cells had weaker migration ability than parental cells in all three cell lines. Additionally, HIF1A related glycolytic mRNA was downregulated in FTD long-treated cell lines compared to that in parental cell lines. Conclusions: Although long-term treatment with FTD induced resistance in colorectal cancer cell lines, no cross-resistance to other drugs (5-FU, L-OHP) and partial resistance to SN-38 that are used in standard chemotherapy was observed. Therefore, FTD is expected to be effective even after treatment with standard chemotherapy. Although FTD/TPI is currently used in the later line, it is suggested from this basic study that FTD/TPI may be applicable to take to the front line therapy. Citation Format: Kenta Tsunekuni, Kazuaki Matsuoka, Takashi Kobunai, Teiji Takechi, Hidetoshi Eguchi, Masaki Mori, Yuichiro Doki, Hideshi Ishii. Continuous trifluridine treatment in colorectal cancer cell lines- investigating its potential [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5266.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
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  • 6
    In: Scientific Reports, Springer Science and Business Media LLC, Vol. 9, No. 1 ( 2019-10-16)
    Abstract: Cancer stem cells (CSCs) are involved in metastatic colorectal cancer recurrence, but no effective therapy targeting these cells is currently available. Because trifluridine (FTD)/tipiracil therapy is used for refractory colorectal cancer, we sought to determine whether FTD is effective against CSC-like cells. CD44 + CD133 + high-expressing and other populations of human DLD-1 colon cancer cells were separately isolated through fluorescence-activated cell sorting. The sphere-forming activity of each population and the anti-sphere-forming effects of FTD and fluorouracil (5-FU) on CD44 + CD133 + cells were then measured. CD44 + CD133 + DLD-1 cells formed substantially more spheres than other cells. Moreover, treating CD44 + CD133 + DLD-1 cells with subtoxic concentrations of FTD (1 µM) inhibited sphere formation, and this was superior to the effect of subtoxic concentrations (1 µM) of 5-FU. The associated inhibition rates for FTD and 5-FU were 58.2% and 26.1%, respectively. Further, CD44 + CD133 + DLD-1 cells expressed higher levels of thymidine kinase 1, which is responsible for FTD phosphorylation, than DLD-1 cells, and FTD was incorporated into the DNA of CD44 + CD133 + DLD-1 cells. Thus, our data show that FTD treatment is effective against CSC-like cells and might be applied as CSC-targeting chemotherapy for tumor subtypes with high CD44 and CD133 expression.
    Type of Medium: Online Resource
    ISSN: 2045-2322
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2019
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  • 7
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2016
    In:  Cancer Research Vol. 76, No. 14_Supplement ( 2016-07-15), p. 5175-5175
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 76, No. 14_Supplement ( 2016-07-15), p. 5175-5175
    Abstract: Background: Tumor responses to antitumor drugs are variable, but predicting these responses is important when selecting effective chemotherapy treatments. Our aim was to identify variations or alterations in gene copy number that influence cancer cells’ susceptibilities to standard chemotherapeutic agents. Methods: Twenty-six human cancer cell lines representing the five main tumor types were subcutaneously implanted into nude mice and tested for sensitivity to fluorinated pyrimidines (UFT, TS-1, 5’-DFUR, and capecitabine), CDDP, CPT-11, and paclitaxel. The cell lines included lung (AOI, LC-11, Lu-99, LX-1, LC-6, Lu-134, Lu-130), colon (KM12C, KM12C/FU, HCT-15, COL-1, CO-3), pancreas (PAN-3, PAN-4, PAN-12, H-48, MIAPaCa-2, BxPC-3), gastric (SC-2, ST-40, 4-1ST, SC-4) and breast (MC-2, MX-1, MDA-MB-435SHM, MDA-MD-231). Genomic DNA was prepared from frozen tumor tissues. Mutations in 48 genes from the TruSeq Amplicon Cancer Panel were screened using the MiSeq system (Illumina, San Diego, CA). Somatic copy number alterations were analyzed by high-density SNP arrays (Affymetrix, Santa Clara, CA). Results: Of the 225 amplicons (187 non-overlapping regions) in the cancer panel, 86% achieved a minimum average sequencing depth of 1000X and the average coverage across all target regions was 5374X. In 26 tumors, sequencing detected 55 somatic mutations in 18 out of 48 cancer related genes of high prognostic or therapeutic significance, such as TP53, APC, PTEN, and SMAD4. Mutation frequencies across 26 xenografts were 73.1% (TP53), 38.5% (KRAS), 15.4% (APC), 11.5% (SMAD4 and RET), 7.7% (BRAF, GNAS, and PTEN), and 3.8% (CTNNB1, GNAQ, HNF1A, HRAS, IDH1, KIT, NOTCH1, PIK3CA, SMO, and STK11). Tumor xenografts with TP53 mutations were significantly less sensitive to CDDP and CPT-11 than wild-type cell lines (P & lt;0.05). The APC mutation conferred resistance to paclitaxel. Copy number gain was observed at 23.1% (KRAS), 15.1% (EGFR), and 11.5% (JAK2 and CDK2NA). Copy number loss was observed at 30.8% (CDK2NA), 19.2% (SMAD4), and 15.4% (PTEN). Cell lines with more copies of CDK2NA and JAK2 were more sensitive to CDDP, while cell lines with fewer copies of PTEN were more sensitive to CDDP. Similarly, copy number gain of CDH1 conferred resistance to UFT, while copy number gain of KRAS sensitized tumors to 5’-DFUR. The copy number of 48 genes determined by the GeneChip array moderately agreed with those estimated by local GC-content adjusted coverage profiles in the sequencing analysis (average Pearson's correlation coefficient = 0.66, 95%CI = 0.54-0.69). Conclusions: Integrated analysis of mutational profiling and gene copy number may be useful to elucidate candidate genes influencing susceptibility of cancer cells to antitumor drugs. Citation Format: Takashi Kobunai, Kenta Tsunekuni, Kazuaki Matsuoka, Hiroshi Tsukihara, Teiji Takechi. Mutational and copy number profiling of cancer-related genes in 26 human tumor xenografts and their correlations with antitumor drug sensitivities. [abstract] . In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5175.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2016
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    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
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