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31.
The present retrospective study aims to determine the clinical value of thymidine labelling index (TLI) together with other established clinical and biological factors in 116 locally advanced breast cancer (LABC) patients treated with anthracycline-based neoadjuvant chemotherapy, surgery, adjuvant chemotherapy and radiotherapy. TLI was determined in 71 LABC patients with a median of 2.62% (0–23.64%) and a mean of 4.71%±5.54. As a result of neoadjuvant chemotherapy, 85 patients (73%) responded to chemotherapy (CT), whereas 31 patients were unresponsive (27%). No relationship has been found between the pretreatment biological variables including TLI, estrogen receptor (ER), progesteron receptor (PgR) status and clinical parameters such as the chemotherapy response rates and axillary lymph node involvement following chemotherapy. Median follow-up was 35 months (18–97 months) and the 3-year overall survival (OS) and disease free survival (DFS) rates were 71.6% and 52.2%, respectively. In univariate analysis, patients with inflammatory breast cancer, high TLI-index (2.62%), lymph node (LN) positivity or >3 positive lymph nodes following neoadjuvant chemotherapy and without any response to neoadjuvant chemotherapy were found to have worse DFS and OS-rates and high local and systemic recurrence rates. In multivariate analysis, TLI was estimated as the most powerful independent factor affecting the OS in LABC patients among the other established clinical and biological parameters (p=0.02). These results suggest that TLI is an important independent indicator of clinical outcome in patients with LABC and these patients with high TLI levels require more effective treatment modalities.  相似文献   
32.

Background:

Potentiation of anticancer activity of capecitabine is required to improve its therapeutic index. In colorectal cancer (CRC) cells, we evaluated whether the histone deacetylase-inhibitor vorinostat may induce synergistic antitumour effects in combination with capecitabine by modulating the expression of thymidine phosphorylase (TP), a key enzyme in the conversion of capecitabine to 5-florouracil (5-FU), and thymidylate synthase (TS), the target of 5-FU.

Methods:

Expression of TP and TS was measured by real-time PCR, western blotting and immunohistochemistry. Knockdown of TP was performed by specific small interfering RNA. Antitumour activity of vorinostat was assessed in vitro in combination with the capecitabine active metabolite deoxy-5-fluorouridine (5′-DFUR) according to the Chou and Talay method and by evaluating apoptosis as well as in xenografts-bearing nude mice in combination with capecitabine.

Results:

Vorinostat induced both in vitro and in vivo upregulation of TP as well as downregulation of TS in cancer cells, but not in ex vivo treated peripheral blood lymphocytes. Combined treatment with vorinostat and 5′-DFUR resulted in a synergistic antiproliferative effect and increased apoptotic cell death in vitro. This latter effect was impaired in cells where TP was knocked. In vivo, vorinostat plus capecitabine potently inhibited tumour growth, increased apoptosis and prolonged survival compared with control or single-agent treatments.

Conclusions:

Overall, this study suggests that the combination of vorinostat and capecitabine is an innovative antitumour strategy and warrants further clinical evaluation for the treatment of CRC.  相似文献   
33.
Background: The first reported case of radiation (XRT) recall related to capecitabine described dermatitis in a previously radiated field in a breast cancer patient (Ortman; JCO). We previously reported the first case of recall syndrome manifesting as diffuse gastritis and duodenitis related to capecitabine with prior XRT with 5-FU in a pancreatic cancer patient (Saif; JARCET). We report here another pancreatic cancer patient with a radiation recall receiving capecitabine following capecitabine-XRT. Patients and methods: From April 2004 to June 2005, 20 patients with locally advanced pancreatic adenocarcinoma were treated with capecitabine 1,600 mg/m2 daily with concomitant radiation (5040cGy) Monday–Friday (weekends off) for a total of 6 weeks, followed by capecitabine 2,000 mg/m2 daily for 14 days every 3 weeks. One male patient with tumor in the neck and body of pancreas and not infiltrating the duodenum dropped hemoglobin to 7.3 g/dl at the end of the ninth week, and melena on rectal examination. Specimen of primary pancreatic ductal adenocarcinoma was obtained via EUS-guided biopsy before starting XRT on day 1 and utilized for RNA extraction. TP mRNA level was determined by real-time quantitative PCR (RT-Q-PCR). Results: Upper endoscopy revealed gastritis consistent with radiation toxicity. Colonoscopy was negative. Transfusion of three units of packed red blood cells (PRBCs) was given. The dose of capecitabine was reduced by 25%. His anemia continued to progress, a CT scan revealed 39% decrease in the tumor size (PR). Analysis of tumor specimen prior to the start of capecitabine-XRT showed TP expression of 183.16 (high). In addition to TP, DPD was 7.40, and TNF-alpha 4,114.56. Conclusion: We believe this case to be the second case of radiation recall presenting as diffuse gastritis in a patient receiving capecitabine after previous treatment with XRT. Further studies, including the role of TP are warranted into the pathogenesis of this unique phenomenon.  相似文献   
34.
AIM: The aim of the present study was to investigate regulatory mechanisms of angiogenesis in the decidua using immortalized human decidual fibroblasts. METHODS: A sample of decidual fibroblasts was taken from a woman in early pregnancy. A cell line, DE-1, was established by infecting the decidual fibroblasts with the simian virus 40 large T antigen. Using this cell line, the ability to produce vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), beta-transforming growth factor (TGF-beta), and thymidine phosphorylase (TP) activity was investigated using immunohistochemistry, and the influences of beta-interleukin-1 (IL-1beta) and alpha-tumor necrosis factor (TNF-alpha) on these angiogenetic factors was investigated using enzyme-linked immunosorbent assays. Furthermore, the effects of TNF-alpha on proliferative capacity and apoptosis induction in DE-1 were studied. RESULTS: It was demonstrated that DE-1 produced all of these angiogenetic factors. The production of VEGF, bFGF and TGF-beta respectively was enhanced by both IL-1beta and TNF-alpha. TP activity was increased by TNF-alpha, but no increase was observed as a result of IL-1beta. It was shown that TNF-alpha suppressed the proliferation of DE-1 cells and significantly increased the percentage of apoptotic cells. CONCLUSION: It is suggested that IL-1beta and TNF-alpha stimulate decidual fibroblasts to up-regulate angiogenesis in the human decidua.  相似文献   
35.
Thymidine phosphorylase (TP), an enzyme involved in pyrimidine metabolism, is identical with an angiogenic factor, platelet-derived endothelial cell growth factor. 2-Deoxy-D-ribose (D-dRib), the degradation product of thymidine generated by TP activity, has been suggested to be a downstream mediator of TP function. 2-Deoxy-L-ribose (L-dRib), a stereoisomer of D-dRib, inhibited the promotion of angiogenesis, tumor growth and metastasis by TP. In our study, we have shown that nude mice inoculated with TP-overexpressing KB/TP cells had shorter survival times than those injected with control KB/CV cells. KB/TP tumors were also more highly invasive than KB/CV tumors in mice. The expression levels of matrix metalloproteinase (MMP)-9 in KB/TP tumors were significantly higher than those in KB/CV tumors. L-dRib and a TP inhibitior, TPI, extended the survival period of KB/TP tumor-bearing mice. L-dRib also reduced MMP-9 mRNA levels in KB/TP tumors. Furthermore, L-dRib suppressed the mRNA level of MMP-9 in cultured KB/TP cells, and the invasive activity of the cells. L-dRib may be useful for the suppression of invasion of TP-expressing tumor cells.  相似文献   
36.
37.
Summary Two cases of McArdle's syndrome are reported. One is a classical exaple; the other is unusual because of the in vitro presence of muscle phosphorylase activity. In the latter case. the electronmicroscopic investigation confirmed the diagnosis.The fine structural changes characteristic of this disease are summarized and it is concluded that histochemical studies alone are insufficient to exclude the diagnosis of McArdle's myopathy.  相似文献   
38.
Summary The role of fetal insulin in placental glycogen accumulation, which occurs despite insulin deficiency in maternal diabetes, was studied in rats. Streptozotocin was injected into fetuses of non-diabetic and streptozotocin-diabetic mothers on days 19.5 and 20.5 of gestation, causing fetal hypoinsulinaemia and pancreatic insulin depletion. Placental glycogen content of either 1.6 mg/g in non-diabetic rats or 6.5 mg/g in diabetic rats was not affected by fetal streptozotocin treatment. Glycogen distribution was also measured in the placenta to assess the effect of fetal hypoinsulinaemia on glycogen content in its fetal segment. The glycogen concentration ratio between the fetal and maternal segments in diabetic rats was 0.3 and increased to 0.5 in diabetic rats, without being affected by fetal hypoinsulinaemia. There was no significant effect of fetal hypoinsulinaemia on the activities of placental glycogen synthase or glycogen phosphorylase, both in nondiabetic and diabetic rats. Fetal hypoinsulinaemia was associated, however, with a marked decrease in fetal liver glycogen together with a decrease in fetal liver weight, which was more pronounced than the decrease in fetal body weight. Administration of insulin to the streptozotocin-treated fetuses restored the impaired glycogen synthesis (measured by incorporation of U-[14C]-glucose and 3H2O in the fetal liver) without affecting glycogen synthesis in the placenta. These results demonstrate: (1) placental glycogen metabolism in contrast to fetal liver glycogen metabolism, is not regulated by fetal insulin; (2) the reduced fetal liver weight and its glycogen content, rather than hyperglycaemia, are the salient features of fetal insulin deficiency; and (3) placental glycogen accumulation in diabetes is related to the hyperglycaemia of maternal origin and not to the changes in maternal or fetal insulin availability.  相似文献   
39.
40.
Hemophagocytic lymphohistiocytosis (HLH) is characterized by uncontrolled immune activation and is traditionally associated with inherited gene defects or acquired causes. In addition to abnormalities in cytotoxic granules and lysosomes, various primary immune deficiency disorders (PID) have been identified among patients suffering from HLH. Our purpose was twofold: to better characterize and detail the association between PID and HLH.  相似文献   
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