Biomedical subjects

Kazuto Nishio

Publications and source records attributed to Kazuto Nishio.

43 records · Page 3Linked to original sources

PubMed2002

Enhanced antitumor activities of TZT-1027 against TNF-alpha or IL-6 secreting Lewis lung carcinoma in vivo.

PURPOSE: TZT-1027, an antimicrotubule agent that inhibits the polymerization of tubulin, shows potent antitumor activity in various transplantable tumor models in vivo. The high antitumor activity of TZT-1027 prompted us to speculate that this compound may have a mode of action other than its antimicrotubule and antimitotic activities. To elucidate the interaction of antitumor cytokines with TZT-1027 in tumors in vivo, we examined the antitumor activity of this agent against various cytokine gene-transfected Lewis lung carcinoma (LLC) cells inoculated into C57BL/6 mice. METHODS: In vitro growth inhibition was evaluated using the MTT assay, and in vivo activity was evaluated in subcutaneous models in C57BL/6 mice. The status of the vasculature in tumor tissues was evaluated immunohistochemically using anti-CD31 antibody. We used a cDNA macroarray to examine the gene expression profiles in tumor tissues removed from mice. RESULTS: TZT-1027 at 3 mg/kg showed potent antitumor activity in Mock (LLC-Neo cells) inoculated mice with a T/C% value of 16%. TZT-1027 at 3 mg/kg showed more potent antitumor activity in LLC-TNF cells and LLC-IL6 cells with T/C% values of 4% and 3%, respectively. TZT-1027 treatment destroyed the tumor vasculature as well as tumor cells in LLC-TNF and LLC-IL6 tissues of mice treated with TZT-1027. The LLC-TNF and LLC-IL6 tissues of mice treated with TZT-1027 had in common the independent alteration of the non-histone chromosomal protein HMG-14 and transcription factor 1 for heat shock gene. Focusing on the gene regulation related to angiogenesis, the alteration in transcriptional factors such as ets family genes and homeobox family genes was remarkable. CONCLUSIONS: These factors are candidates as determinants of the enhanced TZT-1027 antitumor activity in relation to these cytokines.

Animals↗

PubMed2002

Non-cross resistance of ZD0473 in acquired cisplatin-resistant lung cancer cell lines.

ZD0473 is a new generation platinum agent that, in preclinical studies, shows evidence of an extended spectrum of anti-tumor activity and overcomes platinum resistance mechanisms. The drug contains a bulky methylpyridine ligand at its platinum center, which is responsible for its ability to overcome platinum resistance. We examined the growth inhibitory effects of ZD0473 in human lung cancer cell lines resistant to cisplatin in vitro. Four cisplatin resistant human lung cancer cell lines (PC-14/CDDP, SBC-3/CDDP, PC-9/CDDP, H69/CDDP) showed the expected resistance to cisplatin but were non-cross, or much less, resistant to ZD0473, as determined by an MTT assay. A reduction in the intracellular accumulation of cisplatin, but not of ZD0473, was observed in the PC-14/CDDP cells compared with the levels in PC-14 parental cells. The reduction in cisplatin accumulation is considered a major mechanism of the acquired cisplatin resistance in PC-14/CDDP cells. Therefore, the increase in platinum accumulation is considered a possible mechanism underlying the activity of ZD0473 in cisplatin-resistant cells. Glutathione-mediated resistance to cisplatin was also overcome by ZD0473 in PC-14/CDDP cells. In addition, we showed that the intraperitoneal administration of ZD0473 at its maximum tolerable dose in mice produced a marked in vivo antitumor activity against cisplatin-resistant PC-14/CDDP tumors. These results suggest that ZD0473 may be a potent agent in human lung cancer cells with multifactorial cisplatin resistance.

Antineoplastic Agents↗

PubMed2002

Enhanced anti-tumor effect of trastuzumab in combination with cisplatin.

The oncogenenic transmembrane tyrosine kinase receptor HER-2/neu is a promising target for treatment of HER-2-overexpressing cancers. The humanized anti-HER-2/neu antibody Trastuzumab is under clinical evaluation in combination with chemotherapy against breast cancer. The combination of Trastuzumab and cisplatin is expected to be active against HER-2 / neu-expressing tumors. We examined the mechanisms of this combination effect against human solid tumor cells in the presence of human peripheral blood mononuclear cells (PBMCs) using an in vitro MTT assay. The growth-inhibitory effects of cisplatin (CDDP) on the tumor cells were not significantly affected by Trastuzumab in the absence of effector cells. CDDP alone at a dose of less than 12.5 mM did not affect the viability of PBMCs, as determined by MTT assay, suggesting that PBMCs could exert antibody-dependent cell-mediated cytotoxicity (ADCC) at this CDDP concentration. The combination of Trastuzumab and CDDP showed higher cytotoxic effects against the tumor cells in the presence of PBMCs. The CDDP concentration required to inhibit tumor cell growth by 50% was reduced to approximately 20% by Trastuzumab in the presence of PBMCs at an effector/target ratio of 10. It may be important to select combined chemotherapeutic agents which do not diminish the ADCC activity of Trastuzumab via PBMCs. Both the expression of HER-2 / neu and the ADCC activity may be important determinants of the therapeutic benefit of the Trastuzumab/CDDP combination.

Antibodies, Monoclonal↗

PubMed2002

Decreased expression of alpha2,8 sialyltransferase and increased expression of beta1,4 N-acetylgalactosaminyltransferase in gastrointestinal cancers.

Gangliosides such as GD3, GM2, and GD2 are abundantly expressed on the cell surfaces of various malignant cells, suggesting the potential for anti-ganglioside antibody therapy for tumors. Anti-ganglioside GD2 antibody treatment is currently undergoing clinical trials for melanoma and neuroblastoma. We previously reported high in vivo antitumor effects of anti-GM2 ganglioside antibody against lung cancer. To determine whether anti-GM2 antibody may be clinically indicated for gastrointestinal cancers, we evaluated the mRNA expression of alpha2,8 sialyltransferase, a GD3 synthase, and beta1,4 N-acetylgalactosaminyltransferase (beta1,4 GalNAc-T), a GM2/GD2 synthase, in gastrointestinal cancers. We performed modified semi-quantitative RT-PCR, which reduces complexity incidental to radiolabeling on samples taken from small surgically removed clinical specimens. Stomach (19/22) and colorectal (21/30) cancers showed decreased expression of alpha2,8 sialyltransferase as compared with respective normal tissues (P < 0.05). In contrast, increased expression of beta1,4 GalNAc-T was detected in both types of tumors. Clinicopathological analysis revealed significantly higher expression level of alpha2,8 sialyltransferase in the poorly differentiated than in the well-differentiated stomach cancer group (P < 0.05). Furthermore, the expression level of alpha2,8 sialyltransferase was significantly decreased in male as compared with female colorectal cancer patients (P < 0.05). These results suggest that expression level of GM2 ganglioside is elevated in gastrointestinal cancer, and that anti-GM2 antibody may be applicable to its treatment.

Adult↗

PubMedDate not supplied

Differential gene expression profile between PC-14 cells treated with free cisplatin and cisplatin-incorporated polymeric micelles.

Cisplatin (CDDP)-incorporated polymeric micelles (CDDP/m) are a macromolecular carrier system possessing a time-modulated decaying property accompanied by sustained release of free drug. The gene expression profiles in nonsmall cell lung cancer PC-14 cells treated with free CDDP and CDDP/m were evaluated by a cDNA expression array for 807 genes. Although the total gene expression profile of the cells treated with CDDP/m approximated that of free CDDP in the hierarchical clustering analysis, a number of genes showed differential expression according to whether the cells had been treated with CDDP or CDDP/m. Ultimately, 50 genes with significant differential expression between cells treated with CDDP and CDDP/m were selected by principal component (PC) analysis and the unpaired t-test. The genes selected, including genes related to cell cycle regulation, apoptosis-related proteins, detoxification, and DNA repair enzymes, were considered to be related to CDDP-induced cytotoxicity. Interestingly, CDDP/m down-regulated the genes encoding integrins and matrix metalloproteinases (MMPs), which play an integral role in tumor invasion, metastasis, and angiogenesis, whereas free CDDP up-regulated them. The results suggest that use of the macromolecular carriers may yield additional therapeutic effects over free drug.

Animals↗

PubMedDate not supplied

Up-regulated gene expression of angiogenesis factors in post-chemotherapeutic lung cancer tissues determined by cDNA macroarray.

The differential expressions of hundreds of tightly transcriptionally controlled genes in freshly isolated human lung cancers and respective normal lung tissues were analyzed by the cDNA macroarray technique. Three lung cancer patients received pre-operative chemotherapy with cisplatin containing regimens. After chemotherapy, these patients underwent surgery, and poly (A)-RNA expressions of 588 genes in the samples prepared from the lung cancer and normal lung tissues were compared. These expressions of the 588 genes were demonstrated by spotting onto a filter. Histogram analysis of gene expression revealed the tumors to show commonly up-regulated expression of angiogenesis and invasion related genes and adhesion molecules such as fibroblast growth factor 3 (FGFR3), matrix metalloproteinase (MMP)15, 16 and 10, integrin beta 4, integrin alpha 9, endonexin, and several types of collagens. Thus, post-chemotherapeutic tissues from lung cancer parents are characterized by remarkable up-regulation of molecules related to angiogenesis, invasion and adhesion. Tree view showed close clustering of angiogenesis related genes. Furthermore, when the angiogenesis related genes were selected and clustered, they were categorized into three groups depending upon gene expression profiles. These results suggest that angiogenesis related molecules are suitable candidates for target-based therapeutics and angiogenesis inhibitors are expected to be effective in lung cancer patients pretreated with chemotherapy.

Adenocarcinoma↗

PubMedDate not supplied

Gefitinib efficacy associated with multiple expression of HER family in non-small cell lung cancer.

UNLABELLED: The aim of this study was to compare the relationship between HER family expression and clinical response to gefitinib. PATIENTS AND METHODS: Tissues from thirty-one non-small cell lung cancer (NSCLC) patients treated with a monotherapy of gefitinib were analyzed. Expressions of HER family in 31 tumors were examined by immunohistochemistry. RESULTS: The total expressions were 21 for EGFR (68%), 24 for HER2 (77%), 17 for HER3 (55%) and 4 for HER4 (13%). Fourteen out of 31 (45%) demonstrated triple expression of EGFR and HER2, as well as HER3 or HER4. A significantly better response rate (RR) and time to progression (TTP) were observed for the group with the triple expression than for the other groups (RR 50 vs. 11%; p < 0.05, median TTP 4.29 vs. 1.2 months; p < 0.05). CONCLUSION: Mutliple expression of the HER family might be related with the clinical response to gefitinib and EGFR mutation status.

Aged↗