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971.
Yonemori K Katsumata N Kaneko M Uno H Matsumoto K Kouno T Shimizu C Ando M Takeuchi M Fujiwara Y 《Breast cancer research and treatment》2007,103(3):313-318
Summary
Purpose: The aim of this study was to identify the predictors of the response to doxorubicin plus cyclophosphamide in patients with
recurrent breast cancer (RBC) previously treated with anthracycline-containing regimens in a neoadjuvant or adjuvant setting.
Method: Between December 1993 and October 2005, 664 patients had received combined doxorubicin plus cyclophosphamide chemotherapy
(doxorubicin, 40 mg/m2, iv on day 1; cyclophosphamide, 500 mg/m2, iv on day 1, every 21 days) for RBC at our institution. In this study, we retrospectively analyzed the efficacy of doxorubicin
plus cyclophosphamide in 99 of these 664 RBC patients who had also previously been administered an anthracycline-based chemotherapy
in a neoadjuvant or adjuvant setting.
Results: The median cumulative dose of the previously administered anthracycline was 156 mg/m2. The median disease-free interval (DFI) and median anthracycline-free interval were 33.8 and 43.7 months, respectively. The
overall response rate to doxorubicin plus cyclophosphamide therapy was 38.4% (95% CI; range, 28.8–48.0%). The median time
to progression and overall survival were 6.2 and 17.5 months, respectively. The results of a multivariate logistic regression
analysis revealed a significant association of the response to doxorubicin plus cyclophosphamide therapy with the DFI (P = 0.02); human epidermal receptor type 2 (HER2) status also tended to affect the response rate, however the association was
not statistically significant (P = 0.06).
Conclusion: DFI and HER2 status may be associated with the response to repeat utilization of anthracycline-containing regimens in RBC
patients also treated previously with anthracycline-containing chemotherapeutic regimens in a neoadjuvant or adjuvant setting. 相似文献
972.
973.
Salamun Desire Poonkuzhali Balasubramanian Ashish Bajel Biju George Auro Viswabandya Vikram Mathews Alok Srivastava Mammen Chandy 《Medical oncology (Northwood, London, England)》2010,27(4):1046-1049
Functional polymorphisms in the thiopurine methyl transferase (TPMT) gene have been associated with varying levels of enzyme
activity and the occurrence of toxicity related to thiopurines. A total of 98 patients (66 pediatric and 32 adults) with precursor
B acute lymphoblastic leukemia (Pre-B ALL) were evaluated for TPMT gene polymorphisms. The inability to tolerate 6-mercaptopurine
(6-MP) at conventional doses was considered as a surrogate marker of hematologic toxicity. The allele frequency of TPMT*2,
*3A, *3B and *3C in the study population was 0.5, 0, 0 and 2.6%, respectively, similar to the frequency observed in other
Asian populations. Five patients were heterozygous for TPMT*3C variant allele, and one of these patient’s was compound heterozygous
with TPMT*2 variant as the other allele. The impact of TPMT polymorphisms on the toxicity and treatment outcome was assessed
in 66 pediatric patients only, as there was no variant TPMT detected in the adult patients. Three of the 5 patients (60%)
heterozygous for TPMT*2 or TPMT*3C polymorphisms and 12/61 patients (20%) with wild type TPMT genotype had more than 10% of
reduction of 6-MP dose (P = 0.07). The presence of TPMT polymorphisms did not seem to completely explain the variation in 6-MP toxicity in this small
group of patients. Other novel variants in TPMT or variations in the genes involved in transport and biotransformation of
6-MP need to be evaluated in the Indian population. 相似文献
974.
Targeting hypoxia cell signaling for cancer therapy 总被引:7,自引:0,他引:7
Melillo G 《Cancer metastasis reviews》2007,26(2):341-352
975.
Takahiro Hashiba Kenji Oda Keiji Koda Nobuhiro Takiguchi Kazuhiro Seike Masaru Miyazaki 《Gastric cancer》2004,7(4):260-265
We report herein the case of a 70-year-old man who was found to have a gastrointestinal stromal tumor (GIST) in the stomach following sigmoid colon resection. Preoperative gastroscopic and barium examinations revealed a submucosal tumor, measuring 10cm, on the upper part of the stomach. Using computed tomography (CT) images (i.e., computed tomographic volumetry) the doubling time of this tumor was calculated, accurately, as 3.3 months, which suggested a high growth rate and malignancy. A laparotomy and partial gastric resection were performed. Histologically, the tumor consisted of spindle-shaped cells with oval nuclei. In immunohistochemical studies, the tumor cells were positive with respect to c-kit, CD34, and vimentin, but negative with respect to smooth muscle actin and S-100 protein. There were 15–16 mitoses per 50 high-power fields (HPFs), and the Ki-67 antigen (MIB-1) index was 25.5% in the most active areas, which also indicated malignancy. The final pathological diagnosis of this tumor was malignant GIST. The patient was found to have hepatic metastasis 27 months after the surgery, and he subsequently received a hepatic subsegmentectomy. To our knowledge, there are very few reports concerning the growth rate of GISTs. Computed tomographic volumetry is useful for the follow-up of small or irregularly shaped gastric submucosal tumors, and for making decisions regarding surgical intervention. 相似文献
976.
977.
Giovanni Cecchetto Veronique Mosseri Bruno De Bernardi Pierre Helardot Tom Monclair Elisa Costa Ernst Horcher Sylvia Neuenschwander Paolo Tomà Antonino Rizzo Jean Michon Keith Holmes 《Journal of clinical oncology》2005,23(33):8483-8489
PURPOSE: Although tumor resection is the mainstay of treatment for localized neuroblastoma, there are no established guidelines indicating which patients should be operated on immediately and which should undergo surgery after tumor reduction with chemotherapy. In an effort to develop such guidelines, the LNESG1 study defined surgical risk factors (SRFs) based on the imaging characteristics. PATIENTS AND METHODS: A total of 905 patients with suspected localized neuroblastoma were registered by 10 European countries between January 1995 and October 1999; 811 of 905 patients were eligible for this analysis. RESULTS: Information on SRFs was obtained for 719 of 811 patients; 367 without and 352 with SRFs. Of these 719 patients, 201 patients (four without and 197 with SRFs) underwent biopsy only. An attempt at tumor excision was made in 518 patients: 363 of 367 patients without and 155 of 352 patients with SRFs (98.9% v 44.0%). Complete excision was achieved in 271 of 363 patients without and in 72 of 155 patients with SRF (74.6% v 46.4%), near-complete excision was achieved in 81 and 61 patients (22.3% v 39.3%), and incomplete excision was achieved in 11 and 22 patients (3.0% v 14.2%), respectively. There were two surgery-related deaths. Nonfatal surgery-related complications occurred in 45 of 518 patients (8.7%) and were less frequent in patients without SRFs (5.0% v 17.4%). Associated surgical procedures were also less frequent in patients without SRFs (1.6% v 9.7%). CONCLUSION: The adoption of SRFs as predictors of adverse surgical outcome was validated because their presence was associated with lower complete resection rate and greater risk of surgery-related complications. Additional studies aiming to better define the surgical approach to localized neuroblastoma are warranted. 相似文献
978.
Yonglian Guo Xiaoping Zhang Siwei Zhou Zhangqun Ye 《中德临床肿瘤学杂志》2007,6(4):373-377
Objective: To investigate the effects and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of human bladder transitional carcinoma cells BIU-87. Methods: BIU-87 cells were transfected with GFP plasmids containing wild-type PTEN or phosphatase inactivating mutant PTEN (C124A-PTEN) in vitro. The PTEN expression and the phosphorylation levels of focal adhesion kinase (FAK) and protein kinase B (PKB/Akt) were detected by Western blotting. Flow cytometry assay and laser scanning confocal microscopy were used to analyze apoptosis in adherent and non-adherent cells. Results: Compared with the control group; PTEN expression in the cells transfected with wild-type PTEN increased to 210%-260%, while the phosphorylation level of FAK and Akt decreased 59% ( P 〈 0.01) and 89% ( P 〈 0.01), respectively. And the anoikis percentage increased from 8,32 ± 0.57% to 37.62 ± 2.12%, In the cells transfected with C124A-PTEN, neither the phosphorylation of FAK and Akt nor the anoikis percentage had obviously changed, although the PTEN expression enhanced remarkably in comparison with the control. Conclusion: Through its phosphatase activity, tumor suppressor gene PTEN can suppress the phosphorylation of FAK and Akt, and induce anoikis in human bladder transitional carcinoma cells BIU-87. 相似文献
979.
DNA methylation changes measured in pre‐diagnostic peripheral blood samples are associated with smoking and lung cancer risk 下载免费PDF全文
Allison Hodge Manuela Bianca Assumma Chol‐Hee Jung Jessica Chung Francesca Fasanelli Florence Guida Gianluca Campanella Marc Chadeau‐Hyam Kjell Grankvist Mikael Johansson Ugo Ala Paolo Provero Ee Ming Wong Jihoon Joo Dallas R. English Nabila Kazmi Eiliv Lund Christian Faltus Rudolf Kaaks Angela Risch Myrto Barrdahl Torkjel M. Sandanger Melissa C. Southey Graham G. Giles Mattias Johansson Paolo Vineis Gianluca Severi 《International journal of cancer. Journal international du cancer》2017,140(1):50-61
DNA methylation changes are associated with cigarette smoking. We used the Illumina Infinium HumanMethylation450 array to determine whether methylation in DNA from pre‐diagnostic, peripheral blood samples is associated with lung cancer risk. We used a case‐control study nested within the EPIC‐Italy cohort and a study within the MCCS cohort as discovery sets (a total of 552 case‐control pairs). We validated the top signals in 429 case‐control pairs from another 3 studies. We identified six CpGs for which hypomethylation was associated with lung cancer risk: cg05575921 in the AHRR gene (p‐valuepooled = 4 × 10?17), cg03636183 in the F2RL3 gene (p‐valuepooled = 2 × 10 ? 13), cg21566642 and cg05951221 in 2q37.1 (p‐valuepooled = 7 × 10?16 and 1 × 10?11 respectively), cg06126421 in 6p21.33 (p‐valuepooled = 2 × 10?15) and cg23387569 in 12q14.1 (p‐valuepooled = 5 × 10?7). For cg05951221 and cg23387569 the strength of association was virtually identical in never and current smokers. For all these CpGs except for cg23387569, the methylation levels were different across smoking categories in controls (p‐valuesheterogeneity ≤ 1.8 x10 ? 7), were lowest for current smokers and increased with time since quitting for former smokers. We observed a gain in discrimination between cases and controls measured by the area under the ROC curve of at least 8% (p‐values ≥ 0.003) in former smokers by adding methylation at the 6 CpGs into risk prediction models including smoking status and number of pack‐years. Our findings provide convincing evidence that smoking and possibly other factors lead to DNA methylation changes measurable in peripheral blood that may improve prediction of lung cancer risk. 相似文献
980.