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991.
Xiao Qi Wang John M Luk Mercè Garcia-Barcelo Xiaoping Miao Pauline P Leung David W Ho Siu Tim Cheung Brian Y Lam Cindy K Cheung Ashley S Wong Silvana S Lau Man Ting So Wan Ching Yu Qi Cai Karen S Liu Chee Kin Hui George K Lau Ronnie T P Poon John Wong Sheung Tat Fan 《Clinical cancer research》2006,12(17):5248-5252
PURPOSE: Hepatocellular carcinoma (HCC), the most common form of liver cancer, is a leading cause of cancer death worldwide. We previously showed that aberrant mRNA splicing of the liver intestine-cadherin gene CDH17 in liver tissues was triggered by the specific constellation of two CDH17 single nucleotide polymorphisms (651T and IVS6+35G). CDH17 aberrant splicing was highly associated with tumor dissemination and shorter survival of HCC patients. Consequently, it is highly relevant to assess whether the presence of these single nucleotide polymorphisms in the general population represents a risk to the development of HCC. EXPERIMENTAL DESIGN: We conducted a case-control study including 164 HCC and 99 cirrhosis patients and 293 healthy controls. Genotyping was done by PCR and direct sequencing. Odds ratio (OR) and chi2 analysis were used to analyze genotypes and haplotypes. RESULTS: Genotypes 651TT [OR, 2.62; 95% confidence interval (95% CI), 1.34-5.03] and IVS6+35 GG (OR, 1.95; 95% CI, 1.04-3.62) were highly associated with HCC disease. The 651T (C>T) and IVS6+35G (A>G) alleles were also overrepresented in HCC patients and, in particular, the T-G haplotype was the most prevalent in HCC patients when compared with healthy controls (OR, 1.57; 95% CI, 1.167-2.109; P=0.004), which was in agreement with the aberrant splicing observed in tumor tissues. There was no significant difference in genotype and allele frequencies between cirrhosis patients and controls. CONCLUSION: The functional T-G haplotype of CDH17 (651 C>T and IVS6+35A>G) is a genetic susceptibility factor for the development of HCC in a Chinese population. 相似文献
992.
Jeffrey E. Rubnitz MD PhD Stanley Pounds PhD Xueyuan Cao PhD Laura Jenkins BS Gary Dahl MD W. Paul Bowman MD Jeffrey W Taub MD Ching‐Hon Pui MD Raul C. Ribeiro MD Dario Campana MD PhD Hiroto Inaba MD PhD 《Cancer》2012,118(24):6253-6259
BACKGROUND.
Older age has historically been an adverse prognostic factor in pediatric acute myeloid leukemia (AML). To the authors' knowledge, the impact of age relative to that of other prognostic factors on the outcome of patients treated in recent trials is unknown.METHODS.
Clinical outcome and causes of treatment failure of 351 patients enrolled on 3 consecutive protocols for childhood AML between 1991 and 2008 were analyzed according to age and protocol.RESULTS.
The more recent protocol (AML02) produced improved outcomes for patients aged 10 years to 21 years compared with 2 earlier studies (AML91 and AML97), with 3‐year rates of event‐free survival (EFS), overall survival (OS), and cumulative incidence of refractory leukemia or recurrence (CIR) for this group being similar to those of patients aged birth to 9 years: EFS: 58.3% ± 5.4% versus 66.6% ± 4.9% (P = .20); OS: 68.9% ± 5.1% versus 75.1% ± 4.5% (P = .36); and CIR: 21.9% ± 4.4% versus 25.3% ± 4.2% (P = .59). The EFS and OS estimates for patients aged 10 to 15 years overlapped those for patients aged 16 to 21 years. However, the cumulative incidence of toxic death was significantly higher for patients aged 10 to 21 years compared with younger patients (13.2% ± 3.6% vs 4.5% ± 2.0%; P = .028).CONCLUSIONS.
The survival rate for older children with AML has improved on the results of a recent trial and is now similar to that of younger patients. However, deaths from toxicity remain a significant problem for patients in the older age group. Future trials should focus on improving supportive care while striving to develop more effective antileukemic therapy. Cancer 2012. © 2012 American Cancer Society. 相似文献993.
994.
Paul K.S. Chan Alexander R. Chang Mei Y. Yu Wai‐Hon Li May Y.M. Chan Apple C.M. Yeung Tak‐Hong Cheung Tat‐Nga Yau Sze‐Man Wong Ching‐Wai Yau Ho‐Keung Ng 《International journal of cancer. Journal international du cancer》2010,126(1):297-301
Although a second age‐related peak of human papillomavirus (HPV) infection is observed in many populations, it does not seem to have any impact on cervical screening policies. We examined the age‐specific prevalence of HPV infection among 2,604 women enrolled for cervical screening and correlated the age at diagnosis of 2,491 cervical intraepithelial neoplasia Grade 2/3 (CIN2/3) lesions and 801 invasive cervical cancers (ICC). Two peaks of HPV infection were detected at 26–30 and 46–50 years, respectively. The first infection peak was followed by a CIN2/3 peak and an ICC peak at 5–15 and 15 years later, respectively. The second infection peak was followed by an ICC peak 20 years later, but strikingly no CIN2/3 peak was detected in between and thus eliminated an opportunity of treating the lesions at preinvasive stages. The most plausible explanation is that women at the expected second CIN2/3 peak (50–65 years) are not having Pap smears under the current opportunistic screening program. Furthermore, women of this age may have physiological retraction of the transformation zone, and CIN lesions may remain undetected if an adequate Pap smear sample is not obtained. To combat this problem, the screening program in Hong Kong needs to focus on women aged 50 years and older and a mop‐up screening up to 75 years is necessary. Bimodal peaks of HPV infection and cervical cancer are seen in many countries and the analysis of population‐specific age distribution of CIN2/3 should be an integral exercise in evaluating the effectiveness of a screening program. 相似文献
995.
Litian Yu Patricia A. Baxter Horatiu Voicu Sivashankarappa Gurusiddappa Yijue Zhao Adekunle Adesina Tsz-Kwong Man Qin Shu Yu-Jing Zhang Xiu-Mei Zhao Jack M. Su Lazlo Perlaky Robert Dauser Murali Chintagumpala Ching C. Lau Susan M. Blaney Pulivarthi H. Rao Hon-chiu Eastwood Leung Xiao-Nan Li 《Neuro-oncology》2010,12(6):580-594
Limited availability of in vitro and in vivo model systems has hampered efforts to understand tumor biology and test novel therapies for ependymoma, the third most common malignant brain tumor that occurs in children. To develop clinically relevant animal models of ependymoma, we directly injected a fresh surgical specimen from a 9-year-old patient into the right cerebrum of RAG2/severe complex immune deficiency (SCID) mice. All five mice receiving the initial transplantation of the patient tumor developed intracerebral xenografts, which have since been serially subtransplanted in vivo in mouse brains for 4 generations and can be cryopreserved for long-term maintenance of tumorigenicity. The xenograft tumors shared nearly identical histopathological features with the original tumors, harbored 8 structural chromosomal abnormalities as detected with spectral karyotyping, maintained gene expression profiles resembling that of the original patient tumor with the preservation of multiple key genetic abnormalities commonly found in human ependymomas, and contained a small population (<2.2%) of CD133+ stem cells that can form neurospheres and display multipotent capabilities in vitro. The permanent cell line (BXD-1425EPN), which was derived from a passage II xenograft tumor and has been passaged in vitro more than 70 times, expressed similar differentiation markers of the xenograft tumors, maintained identical chromosomal abnormalities, and formed tumors in the brains of SCID mice. In conclusion, direct injection of primary ependymoma tumor cells played an important role in the generation of a clinically relevant mouse model IC-1425EPN and a novel cell line, BXD-1425EPN. This cell line and model will facilitate the biological studies and preclinical drug screenings for pediatric ependymomas. 相似文献
996.
Her‐Young Su Hung‐Cheng Lai Ya‐Wen Lin Chin‐Yun Liu Chi‐Kuan Chen Yu‐Ching Chou Shin‐Ping Lin Wen‐Chi Lin Hsin‐Yi Lee Mu‐Hsien Yu 《International journal of cancer. Journal international du cancer》2010,127(3):555-567
Oncogenic activation of the Wnt signaling pathway is common in cancers, but mutation of β‐catenin in ovarian cancer is rare. In addition to genetic events, epigenetic modification of secreted frizzled‐related protein (SFRP) family has been shown to be important in regulating Wnt signaling. Although high degree of homology is observed in the same family, different SFRPs may have opposing effects on the same process. We reported recently that a Wnt antagonist, SFRP5, is downregulated frequently through promoter hypermethylation and that this hypermethylation is associated with overall survival in ovarian cancer. The aim of this study was to analyze the function of SFRP5 in ovarian cancer. Functional assays including measuring cell proliferation, invasion, colony formation and xenograft were performed using ovarian cancer cell lines with overexpression of SFRP5 or a short hairpin RNA silencing. The methylation status of SFRP5 in relation to cisplatin resistance in ovarian cancer patients was analyzed. Restoration of the expression of SFRP5 attenuated Wnt signaling in ovarian cancer cells and suppressed cancer cell growth, invasion of cells and tumorigenicity in mice. These effects were independent of the canonical pathway. The expression of SFRP5 inhibited epithelial–mesenchymal transition (EMT). The restoration of SFRP5 downregulated AKT2 and sensitized ovarian cancer cells to chemotherapy. These effects are consistent with the poor response to platinum‐based chemotherapy in patients with methylation of SFRP5. Our data suggested that epigenetic silencing of SFRP5 leads to oncogenic activation of the Wnt pathway and contributes to ovarian cancer progression and chemoresistance through the TWIST‐mediated EMT and AKT2 signaling. 相似文献
997.
998.
Risk of hemophagocytic lymphohistiocytosis in adults with fevers of unknown origin: the clinical utility of a new scoring system on early detection 下载免费PDF全文
Hao‐Yuan Wang Ching‐Fen Yang Tzeon‐Jye Chiou Sheng‐Hsiang Yang Jyh‐Pyng Gau Yuan‐Bin Yu Po‐Min Chen Hui‐Chi Hsu Chang‐Phone Fung Hsiao‐Yi Lin Cheng‐Hwai Tzeng Jin‐Hwang Liu Liang‐Tsai Hsiao 《Hematological oncology》2017,35(4):835-844
The diagnosis of hemophagocytic lymphohistiocytosis (HLH) is delayed by most physicians. This study aimed to identify early parameters and suitable scoring systems for the risk of HLH. Clinical and laboratory data collected ≤3 days after admission were defined as early parameters and used to calculate the number of HLH‐2004 criteria met and bone marrow (BM) score. Between January 2006 and February 2016, 233 immunocompetent adults with naïve fever of unknown origin who underwent a BM study were enrolled to mimic patients at risk of HLH and randomly assigned into the developmental or validation cohort. Hemophagocytic lymphohistiocytosis was finally diagnosed in 47 patients, with non‐Hodgkin lymphoma as the major etiology (51.1%). Upon admission, four‐fifths of patients who developed subsequent HLH fulfilled ≤3 of 8 HLH‐2004 criteria, and 6 early parameters were independent predictors of HLH: anemia (hemoglobin < 10 g/dL), thrombocytopenia (platelet count < 100 × 103/μL), leukoerythroblastosis, hyperbilirubinemia (total bilirubin > 2 × upper normal limit), hyperferritinemia (ferritin > 1000 ng/mL), and splenomegaly. Compared with the HLH criteria met upon admission, the BM score was an independent predictor (odds ratio = 1.621; 95% confidence interval, 1.355‐1.940) with excellent discrimination (area under the receiver operating characteristic curve = 0.920; 95% confidence interval, 0.883‐0.958). The sensitivity and specificity for a BM score cutoff of 10 points were 95% and 75%, respectively. When approaching immunocompetent adults with a continuously high fever, the BM score at initial admission assists with early identification of patients at risk of HLH. 相似文献
999.
Sodium alginate, a biopolymer, was employed in the formulation of matrix tablets. They cracked or laminated at acidic pH, compromising their dissolution performance. Improved mechanical strength and reduced barrier permeability of calcium alginate gel provided the rationale for cross-linking the alginate matrix to sustain drug release. Studies had suggested that the incorporation of soluble calcium salts in alginate matrix tablets could sustain drug release at near-neutral pH due to in situ cross-linking. However, results from the present study showed otherwise when gastrointestinal pH conditions were simulated. Significant reduction in drug release rate was only observed when an external calcium source was utilized at low concentration. High calcium ion concentrations caused matrix disintegration. In contrast, matrices pre-coated by calcium alginate could sustain drug release at pH 1.2 followed by pH 6.8 for over 12h. The presence of cross-linked barrier impeded matrix lamination and preserved matrix structure, contributing to at least three-fold reduction in drug release at pH 1.2. Zero order release as well as delayed burst release could be achieved by employing appropriate grade of alginate and cross-linking conditions. 相似文献
1000.