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991.
Aizawa S Nakano M Iwase O Yaguchi M Hiramoto M Hoshi H Nabeshima R Shima D Handa H Toyama K 《Leukemia research》1999,23(3):239-246
We examined the supportive function of stromal cells from patients with refractory anemia (RA) of myelodysplastic syndrome (MDS) on CD34-positive hematopoietic cell proliferation and differentiation using a long-term bone marrow culture (LTMC) system. Primary marrow stromal cells were obtained from 11 MDS RA patients and 12 healthy volunteers, and freshly prepared CD34-positive bone marrow cells from a normal subject were inoculated onto the stroma. There seems to be three broad patterns of hematopoietic cell growth in the LTMCs. In one group, hematopoietic cells were maintained at near normal levels (type A). In the second group, the number of hematopoietic cells increased within the first 5-10 days of culture, but declined to low levels at 15-20 days of culture as compared with normal control (type B). In the third group, the incidence of hematopoietic cells steadily declined from the beginning of the culture (type C). Furthermore, apoptotic change of hematopoietic cells was very frequently observed in cultures with the type C stroma, which were especially defective for supporting CD34 + cell proliferation and differentiation. The expression of CD95 on hematopoietic cells was induced by the type C stroma, however, production of fas ligand by the stromal cells was not observed. These findings suggest a lack of hematopoietic supportive function in some cases of MDS RA and also indicate that there is heterogeneity of stromal function among MDS RA patients. 相似文献
992.
Background: Although it is important to achieve a good death in Japan, there have been no studies to explore factors associated with a good death. The aim of this study was to explore factors contributing to a good death from the bereaved family members' perspectives, including patient and family demographics and medical variables. Methods: A cross‐sectional anonymous questionnaire survey for bereaved family members of cancer patients who had died in a regional cancer center and a medical chart review were conducted. We measured the results from the Good Death Inventory and family demographics. In addition, we extracted patient demographics, medical variables, and medical interventions in the last 48 h before death from a medical chart review. Results: Of the 344 questionnaires sent to bereaved family members, 165 responses were analyzed (48%). We found, first, that death in the palliative care unit was more likely to be described as a good death compared with death on a general ward. Some significant characteristics were ‘environmental comfort,’ ‘physical and psychological comfort,’ ‘being respected as an individual,’ and ‘natural death.’ Second, we found that a patient's and family member's age and other demographic factors significantly correlated with an evaluation of a good death. In addition, life prolongation treatment and aggressive treatment such as chemotherapy in the last 2 weeks of life were barriers to attainment of a good death. Moreover, appropriate opioid medication contributed to a good death. Conclusion: Withholding aggressive treatment and life‐prolonging treatment for dying patients and appropriate opioid use may be associated with achievement of a good death in Japan. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
993.
Histone deacetylase inhibitors (HDACis) have shown significant antiproliferative and apoptotic properties in various types of cancer cells, including prostate cancer cells, and are therefore being evaluated as a treatment modality. However, the mechanism by which sodium butyrate (SB) induces apoptosis is not completely understood. We focused on SB which exists in the intestine and is therefore expected to have less adverse effects. In this study, three prostate cancer cell lines (LNCaP, DU145 and PC-3) were treated in vitro with different concentrations of SB. Cell proliferation was studied by the XTT assay; cell cycle analysis and induction of apoptosis were studied by laser scanning cytometry. Western blot analysis was used to study p21, p27, CDK2, CDK4, CDK6, caspase-3, caspase-7, Fas, FADD, TRADD, Bcl-2 and Bax protein expression. SB inhibited cell growth and induced apoptosis in a concentration-dependent manner in human prostate cancer cells (LNCaP, DU145 and PC-3). Western blot analysis showed dose-dependent increases of p21 levels in DU145 and PC-3 cells, and dose-dependent decreases of CDK2, CDK4, CDK6 and procaspase-3 protein levels in all three prostate cancer cell lines. Bcl-xL was significantly down-regulated in DU145 cells, and Bcl-2 was significantly down-regulated in PC-3 and LNCaP cells. No significant changes were observed in procaspase-7, TRADD and Bax expression, although slight decreases in Fas and FADD expression were seen in all three prostate cancer cell lines. Analysis of cell morphology using laser scanning microscopy detected condensed and fragmented nuclei. In conclusion, SB induces G1 and G2 arrest by increasing p21 expression resulting in CDK2, CDK4 and CDK6 down-regulation. SB potently induced apoptosis, which was accompanied by DNA fragmentation, down-regulated Bcl-2 in LNCaP and PC-3 cells, Bcl-xL in DU145 cells, and down-regulated procaspase-3, but not procaspase-7, in these human prostate cancer cell lines. These results suggest that SB may serve as a new modality for the treatment of hormone refractory prostate cancer. 相似文献
994.
Tozer GM Akerman S Cross NA Barber PR Björndahl MA Greco O Harris S Hill SA Honess DJ Ireson CR Pettyjohn KL Prise VE Reyes-Aldasoro CC Ruhrberg C Shima DT Kanthou C 《Cancer research》2008,68(7):2301-2311
Tubulin-binding vascular-disrupting agents (VDA) are currently in clinical trials for cancer therapy but the factors that influence tumor susceptibility to these agents are poorly understood. We evaluated the consequences of modifying tumor vascular morphology and function on vascular and therapeutic response to combretastatin-A4 3-O-phosphate (CA-4-P), which was chosen as a model VDA. Mouse fibrosarcoma cell lines that are capable of expressing all vascular endothelial growth factor (VEGF) isoforms (control) or only single isoforms of VEGF (VEGF120, VEGF164, or VEGF188) were developed under endogenous VEGF promoter control. Once tumors were established, VEGF isoform expression did not affect growth or blood flow rate. However, VEGF188 was uniquely associated with tumor vascular maturity, resistance to hemorrhage, and resistance to CA-4-P. Pericyte staining was much greater in VEGF188 and control tumors than in VEGF120 and VEGF164 tumors. Vascular volume was highest in VEGF120 and control tumors (CD31 staining) but total vascular length was highest in VEGF188 tumors, reflecting very narrow vessels forming complex vascular networks. I.v. administered 40 kDa FITC-dextran leaked slowly from the vasculature of VEGF188 tumors compared with VEGF120 tumors. Intravital microscopy measurements of vascular length and RBC velocity showed that CA-4-P produced significantly more vascular damage in VEGF120 and VEGF164 tumors than in VEGF188 and control tumors. Importantly, this translated into a similar differential in therapeutic response, as determined by tumor growth delay. Results imply differences in signaling pathways between VEGF isoforms and suggest that VEGF isoforms might be useful in vascular-disrupting cancer therapy to predict tumor susceptibility to VDAs. 相似文献
995.
Adherence of multiple myeloma cells to bone marrow stromal cells upregulates vascular endothelial growth factor secretion: therapeutic applications. 总被引:29,自引:0,他引:29
D Gupta S P Treon Y Shima T Hideshima K Podar Y T Tai B Lin S Lentzsch F E Davies D Chauhan R L Schlossman P Richardson P Ralph L Wu F Payvandi G Muller D I Stirling K C Anderson 《Leukemia》2001,15(12):1950-1961
Increased angiogenesis has recently been recognized in active multiple myeloma (MM). Since vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are two key mediators of angiogenesis, we characterized the production of VEGF, b-FGF and interleukin-6 (IL-6) (a MM growth and survival factor) in MM cell lines and Epstein-Barr virus (EBV) transformed B cell lines from MM patients, patient MM cells, as well as bone marrow stromal cells (BMSCs) from normal healthy donors and MM patients. We detected secretion of VEGF, but no bFGF and IL-6, in MM cell lines (MM.1S, RPMI 8226 and U266); EBV transformed B cell lines from MM patients (IM-9, HS-Sultan and ARH77); MM cell lines resistant to doxorubicin (RPMI-DOX40), mitoxantrone (RPMI-MR20), melphalan (RPMI-LR5) and dexamethasone (MM.1R); and patient MM cells (MM1 and MM2). BMSCs from MM patients and normal donors secreted VEGF, b-FGF and IL-6. Importantly, when MM cells were adhered to BMSCs, there was a significant increase in VEGF (1.5- to 3.1-fold) and IL-6 (1.9- to 56-fold) secretion. In contrast, the bFGF decreased in co-cultures of BMSCs and MM cells. Paraformaldehyde fixation of BMSCs or MM cells prior to adhesion revealed that VEGF was produced both from BMSCs and MM cells, though it may come primarily from BMSCs in some cultures. IL-6 was produced exclusively in BMSCs, rather than MM cells. Moreover, when MM cells were placed in Transwell insert chambers to allow their juxtaposition to BMSCs without cell to cell contact, induction of VEGF and IL-6 secretion persisted, suggesting the importance of humoral factors. Addition of exogenous IL-6 (10 ng/ml) increased VEGF secretion by BMSCs. Conversely, VEGF (100 ng/ml) significantly increased IL-6 secretion by BMSCs. Moreover, anti-human VEGF (1 microg/ml) and anti-human IL-6 (10 microg/ml) neutralizing antibodies reduced IL-6 and VEGF secretion, respectively, in cultures of BMSCs alone and co-cultures of BMSCs and MM cells. Finally, thalidomide (100 microM) and its immunomodulatory analog IMiD1-CC4047 (1 microM) decreased the upregulation of IL-6 and VEGF secretion in cultures of BMSCs, MM cells and co-cultures of BMSCs with MM cells. These data demonstrate the importance of stromal-MM cell interactions in regulating VEGF and IL-6 secretion, and suggest additional mechanisms whereby thalidomide and IMiD1-CC4047 act against MM cells in the BM millieu. 相似文献
996.
To investigate the relationship between the expression of connexin in basaloid squamous cell carcinomas (BSCC) and their rapid proliferation and invasive potential, we examined the effect of overexpression of connexin 43 (Cx43) in a BSCC-derived cell line (BSC-OF). BSC-OF was transfected with Cx43 to obtain 15 clones with a stable expression of Cx43. In these cells, although Cx43 was distributed throughout the cytoplasm, it did not form connexon plaque. In almost all of the clones, cell proliferation was clearly suppressed. Furthermore, we investigated cell migration and invasion in three clones that showed a remarkable down-regulation in cell growth, and found that Cx43 transfection showed no significant effect on either. These results suggest that Cx43 plays a role as a tumor suppressor in the cytoplasm of Cx43-transfected BSC-OF cells. However, no definite correlation was found between Cx43 and cell migration and invasion. 相似文献
997.
Degradation of bradykinin (BK) in human plasma was investigated by searching for a stable metabolite as a marker of kinin release in vivo. BK, incubated with diluted plasma, was degraded to des-Arg9-BK (des-9-BK), des-Phe8-Arg9-BK (des-8,9-BK) and Arg-Pro-Pro-Gly-Phe ([1-5]BK). Des-9-BK was degraded to [1-5]BK without an increase in des-8,9-BK, and des-8,9-BK was also degraded to [1-5]BK. D,L-2-Mercaptomethyl-3-guanidinoethyl-thiopropanoic acid inhibited the formation of des-9-BK from BK, whereas captopril inhibited the formation of des-8,9-BK from BK as well as that of [1-5]BK from des-9-BK or des-8,9-BK. The half lives of BK, des-9-BK, des-8,9-BK and [1-5]BK under the present experimental conditions were 60 min, 90 min, 14 min and 4.2 hr, respectively. Among the metabolites, [1-5]BK was the most stable one and may be used as a marker for BK production in vivo. 相似文献
998.
Toshiyuki Shima Masayuki Shimoda Takao Shigenobu Takashi Ohtsuka Tomoyasu Nishimura Katsura Emoto Yuichiro Hayashi Tatsuro Iwasaki Takayuki Abe Hisao Asamura Yae Kanai 《Cancer science》2020,111(2):727-738
Programmed death‐ligand 1 (PD‐L1) is an immune modulator that promotes immunosuppression by binding to programmed death‐1 of T‐lymphocytes. Although tumor cell PD‐L1 expression has been shown to be associated with the clinical response to anti–PD‐L1 antibodies, its concise regulatory mechanisms remain elusive. In this study, we evaluated the associations of tumor PD‐L1 expression and immune cell infiltrating patterns in 146 cases of early lung adenocarcinoma (AC) to investigate the possible extrinsic regulation of tumor PD‐L1 by immune cells. Using immunohistochemistry, cell surface PD‐L1 expression in tumor cells was observed in 18.5% of stage 0‐IA lung AC patients. Tumor PD‐L1 positivity was significantly associated with stromal invasion, which was accompanied by increased tumor‐associated macrophages (TAM), CD8+ cytotoxic T cells and FoxP3+ regulatory T cells. Among these immune cells, TAM and CD8+ T cells significantly accumulated in PD‐L1‐positive carcinoma cell areas, which showed a tumor cell nest‐infiltrating pattern. Although CD8+ T cells are known to induce tumor PD‐L1 expression via interferon‐? production, the increased TAM within tumors were also associated with tumor cell PD‐L1 positivity, independently of CD8+ T cell infiltration. Our in vitro experiments revealed that PD‐L1 expression in lung cancer cell lines was significantly upregulated by co–culture with M2‐differentiated macrophages; expression of PD‐L1 was reduced to baseline levels following treatment with a transforming growth factor‐β inhibitor. These results demonstrated that tumor‐infiltrating TAM are extrinsic regulators of tumor PD‐L1 expression, indicating that combination therapy targeting both tumor PD‐L1 and stromal TAM might be a possible strategy for effective treatment of lung cancer. 相似文献
999.
Fujiwara H Ishida C Maruguchi M Shima Y 《Gan to kagaku ryoho. Cancer & chemotherapy》2000,27(Z3):649-652
The subjects for this study were patients in remission discharged from the Palliative Care Unit (PCU) between January 1 and December 31, 1999. There were 72 patients, which represents 22% of all discharged patients during the same period. The objective of this study was to clarify nursing intervention in the transition from admission to the PCU to the transfer to home care and primary factors in this process. The study of medical records and inquiries made of primary nurses served as methods for this. Unless patients or their families have the desire to shift to home care, the transfer is difficult. However, as a result of information provisioning and coordination through nursing intervention concerning the home care support system, the transfer to home care was possible for 22% of all discharged patients. Primary factors in the transfer to home care are that: 1. patients have the desire to shift to home care; 2. patients' families accept home care; 3. symptoms are controlled to the level sought by the patients; 4. patient's clinical process can be observed continuously by the PCU outpatient clinic; and 5. there are adequate preparations to receive patients in an emergency. 相似文献