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121.
PURPOSE: To investigate the gefitinib, fluorouracil (FU), leucovorin, and oxaliplatin regimen (IFOX) in previously treated patients with metastatic colorectal cancer. PATIENTS AND METHODS: Eligible patients had stage IV colorectal adenocarcinoma and had demonstrated progression or intolerance to a prior chemotherapy regimen not including oxaliplatin. Each cycle consisted of 14 days. Cycle 1 consisted of oxaliplatin 85 mg/m2 intravenously (IV) during 2 hours on day 1, hours 0 to 2; leucovorin 200 mg/m2 IV on days 1 and 2, hours 0 to 2; FU 400 mg/m2 IV push on days 1 and 2; and FU 600 mg/m2 IV on days 1 and 2, hours 2 to 24 (FOLFOX-4). All subsequent cycles consisted of FOLFOX-4 with gefitinib at 500 mg/d administered orally throughout the 14-day cycle. RESULTS: Twenty-seven patients were enrolled onto the study. The median number of prior chemotherapy regimens was two, and 74% of all patients received prior irinotecan. Nine of the 27 patients (33%) and six of the 20 patients (30%) who had prior FU and irinotecan had a partial response by Response Evaluation Criteria in Solid Tumors Group criteria. Median overall survival was 12.0 months. Median event-free survival was 5.4 months. Grade 3 to 4 toxicities included neutropenia (48%), diarrhea (48%), nausea (22%), and vomiting (15%). CONCLUSION: IFOX is an active regimen in patients with previously treated metastatic colorectal adenocarcinoma, demonstrating higher response rates than those reported with FOLFOX-4 alone in a similar patient population.  相似文献   
122.
PURPOSE: Cysteine-rich 61 (Cyr61/CCN1) is involved in many different types of tumor development and progression. Nonetheless, the role of Cyr61 in human gastric cancer has not yet been fully characterized.Experimental design: We addressed the issue by immunohistochemical staining of 81 gastric adenocarcinoma specimens. Liposome-mediated transfection was used to introduce a Cyr61 expression vector into gastric cancer AGS cell lines. Transfectants were tested in invasion assay by a Boyden chamber. Furthermore, a cyclooxygenase-2 (COX-2) reporter assay and gel mobility shift assay were done to investigate the potential signal pathway of Cyr61. RESULTS: Patients with gastric adenocarcinoma whose tumor displayed high expression of Cyr61 correlated well with aggressive lymph node metastasis, more advanced tumor stage, histologic diffuse type, and early recurrence. Stable transfection of Cyr61 into the AGS cell line strongly enhanced its invasive activity. The overexpression of Cyr61 into AGS cells significantly increased the expression of COX-2 mRNA, protein, and enzymatic activity. Gel mobility shift assays further showed that the nuclear factor-kappaB (NF-kappaB) pathway was evidently activated in Cyr61-expressing AGS cells. Function-neutralizing antibody to alphavbeta3 but not alphavbeta5 effectively suppressed Cyr61-mediated NF-kappaB activation, COX-2 gene expression, and cell invasiveness. CONCLUSIONS: Cyr61 may contribute to the malignant progression of gastric cancer by promoting tumor cell motility/invasion through up-regulation of the functional COX-2 via an integrin alphavbeta3/NF-kappaB-dependent pathway.  相似文献   
123.
124.
目的:研究复方中药艾迪注射液对白血病耐药细胞株K562/ADM细胞体外生长和增殖周期的影响。方法:采用细胞体外培养技术,台盼兰染色计数法观察活细胞数量变化并绘制细胞生长曲线,细胞集落形成实验,MTT法检测生长抑制率,光学显微镜、透射电镜观察细胞形态变化.流式细胞仪测定细胞增殖周期。结果:艾迪注射液对KS62/ADM细胞生长和增殖活力均有明显的抑制作用,作用随艾迪注射液剂量和作用时间的增加而增加,呈量效、时效关系,与对照组比较,P〈0.05。流式细胞分析显示它能抑制细胞周期,减少G1期的比例,增加S期和G2期的比例,并能明显诱导细胞凋亡,尤以中、高剂量组和联合用药组为明显,在光镜、透射电镜下观察到较为典型的细胞凋亡形态。结论:艾迪注射液有明显的抗肿瘤活性,能抑制K562/ADM细胞的生长和增殖,调控细胞增殖周期并诱导凋亡。  相似文献   
125.
Curcumin (diferuloylmethane) is a phenolic compound present in turmeric and is ingested daily in many parts of the world. Curcumin has been reported to cause inhibition on proliferation and induction of apoptosis in many human cancer cell lines, including non‐small cell lung cancer cells (NSCLC). However, the clinical application of curcumin is restricted by its low bioavailability. In this report, it was observed that combined treatment of a low dosage of curcumin (5–10 µ m ) with a low concentration (0.1–2.5 µ m ) of small molecule inhibitors, including AG1478, AG1024, PD173074, LY294002 and caffeic acid phenethyl ester (CAPE) increased the growth inhibition in two human NSCLC cell lines: A549 and H1299 cells. The observation suggested that combined treatment of a low dosage of curcumin with inhibitors against epidermal growth factor receptor (EGFR), insulin‐like growth factor 1 (IGF‐1R), fibroblast growth factors receptor (FGFR), phosphatidylinositol 3‐kinases (PI3K) or NF‐κB signaling pathway may be a potential adjuvant therapy beneficial to NSCLC patients. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
126.

Background:

In addition to lung cancers, tuberculosis infections have been associated with increased risk of non-pulmonary malignancies in case reports. Our population-based study employed standardized incidence ratios (SIRs) to systemically survey non-pulmonary cancer risks after tuberculosis infections.

Methods:

Data of patients who had newly diagnosed tuberculosis, were aged 20 years or older, and had no prior cancer or tuberculosis were sampled from the Taiwan National Health Insurance database between 2000 and 2010. SIRs compared cancer incidence in patients with tuberculosis infections to the general population. SIRs of specific cancers were further analyzed with respect to gender and time after tuberculosis infections.

Results:

After a follow-up period of 28 866 person–years, 530 tuberculosis cases developed cancers compared with 256 cases in the general populations (2.07, 95% confidence interval (CI), 1.90–2.26). The SIR of non-pulmonary malignancies was also increased (1.71, 95% CI, 1.54–1.90). For males, SIRs were increased within 1 year after tuberculosis diagnosis for the following cancers: head and neck, esophageal, colorectal, liver, lung, melanomas, and Hodgkin''s disease. SIRs were increased for liver, biliary, lung, and bladder cancers beyond the first year after tuberculosis diagnosis. For females, SIRs were increased for leukemia, esophageal, and lung cancers within the first year, and only for leukemia beyond 1 year post diagnosis.

Conclusion:

Having found increased risks of several cancers that differ with gender and time after tuberculosis diagnosis, physicians may consider these factors in patients following tuberculosis diagnosis.  相似文献   
127.
背景与目的:骨肉瘤是临床常见的成骨性恶性肿瘤,预后差.Livin是近年来发现的人凋亡抑制蛋白家族的新成员,特异性高表达于某些实体肿瘤组织,能抑制细胞凋亡.胎盘生长因子(placental growth factor,PlGF)在肿瘤等病理性血管生成中发挥着极为重要的作用.本研究旨在探讨Livin及PlGF在骨肉瘤中的表达,分析两者在骨肉瘤的临床诊断及治疗中的意义.方法:应用免疫组化方法检测本院骨科于2003年-2008年间收治的57例骨肉瘤患者的肿瘤组织及10例正常骨组织标本中Livin及PlGF的表达,根据阳性细胞百分比和染色强弱判断两者的表达水平,分析两者表达的相关性及与骨肉瘤各项临床病理指标之间的关系.结果:Livin与PlGF在57例骨肉瘤患者的肿瘤组织中阳性表达率分别为52.6%和64.9%,而在10例正常骨组织中均不表达,两组之间的差异有统计学意义(P<0.05).Livin与PlGF阳性表达与骨肉瘤大小及Enneking分期相关,与患者年龄、性别、病理分型及肿瘤部位无关;Livin的阳性表达与PlGF的阳性表达之间无相关性(P=0.642).结论:Livin及PlGF均在骨肉瘤中高表达,并与骨肉瘤的肿瘤大小及Enneking分期呈正相关,可能与骨肉瘤的发生、发展相关.  相似文献   
128.
Kuo ML  Chuang SE  Lin MT  Yang SY 《Oncogene》2001,20(6):677-685
Interleukin-6 (IL-6) is a pleitrophic cytokine that not only regulates growth and differentiation of many cell types, but also induces production of acute phase proteins (AAP) in hepatocytes. Our previous works have demonstrated that both PI 3-K/Akt and STAT3 pathways were concomitantly activated and cooperatively mediated the anti-apoptotic effect of IL-6. This investigation reports that IL-6 protected cells against apoptosis induced by a variety of agents including, TGF-beta, UV and retinoic acid (RA) in Hep3B cells, suggesting that IL-6 is a fundamental determinant of hepatic cell survival. Mcl-1, but not other Bcl-2 family members, was rapidly up-regulated by IL-6, with a peak (approximately 3-4-fold) appearing at 4 h. Transient transfection of cells with a mcl-1 antisense vector, resulting in a 50-60% reduction of the anti-apoptotic effect of IL-6, indicating that Mcl-1 is a downstream effector of IL-6. Which signaling pathway transduced by IL-6 responsible for the Mcl-1 up-regulation was further investigated. In Hep3B cells, the JAK/STAT3, ERK, and PI 3-K/Akt pathways were activated by IL-6 stimulation. Blocking JAK/STAT3 activation with a dominant-negative mutant STAT3F or a JAK inhibitor AG490 could not influence IL-6-mediated Mcl-1 up-regulation. Similarly, PD98059 treatment, a MEK specific inhibitor, also failed to inhibit Mcl-1 expression. However, the IL-6-induced Mcl-1 up-regulation was effectively attenuated in the presence of PI 3-K inhibitors, LY294002 and wortmannin. Expression of dominant-negative Akt, but not Etk, could abrogate the IL-6-induced increase of Mcl-1. In conclusion, our results suggest that the anti-apoptotic effect of IL-6 is mediated, at least in part, by Mcl-1 expression and that is mainly through the PI 3-K/ Akt-dependent pathway.  相似文献   
129.
The relative timing of genetic alterations that contribute to follicular lymphoma remains unknown. We analyzed a donor-recipient pair who both developed grade 2/3A follicular lymphoma 7 years after allogeneic transplantation and donor lymphocyte infusions. Both patients harbored identical BCL2/IGH rearrangements also present in 1 in 2,000 cells in the donor lymphocyte infusion, and the same V(D)J rearrangement, which underwent somatic hypermutation both before and after clonal divergence. Exome sequencing of both follicular lymphomas identified 15 shared mutations, of which 14 (including alterations in EP300 and KLHL6) were recovered from the donor lymphocyte infusion by ultra-deep sequencing (average read coverage, 361,723), indicating acquisition at least 7 years before clinical presentation. Six additional mutations were present in only one follicular lymphoma and not the donor lymphocyte infusion, including an ARID1A premature stop, indicating later acquisition during clonal divergence. Thus, ultrasensitive sequencing can map clonal evolution within rare subpopulations during human lymphomagenesis in vivo. SIGNIFICANCE: For the first time, we define the molecular ontogeny of follicular lymphoma during clonal evolution in vivo. By using ultrasensitive mutation detection, we mapped the time-course of somatic alterations after passage of a malignant ancestor by hematopoietic cell transplantation.  相似文献   
130.
The pathogenesis of hepatocellular carcinoma (HCC) involves many molecular pathways. Glycine N‐methyltransferase (GNMT) is downregulated in almost all HCC and its gene knockout mice developed HCC with high penetrance. We identified PREX2, a novel PTEN inhibitor, as a GNMT‐interacting protein. Such interaction enhanced degradation of PREX2 through an E3 ligase HectH9‐mediated proteasomal ubiquitination pathway. Depletion of GNMT or HectH9 resulted in AKT activation in a PREX2 dependent manner and enhanced cell proliferation. An elevated PREX2 protein expression accompanied by activation of AKT was observed in the liver of Gnmt knockout mice. PREX2 protein expression was upregulated in 54.9% of human HCC samples, while its mRNA level was comparable in tumor and tumor‐adjacent tissue, suggesting a post‐translational alteration of PREX2 expression. Higher level of PREX2 in the tumor tissues was associated with poorer survival. These results reveal a novel mechanism in which GNMT participates in AKT signaling and HCC tumorigenesis by promoting HectH9‐mediated PREX2 degradation.  相似文献   
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