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A patient from the University of California Los Angeles Medical Center who developed cutaneous vasculitis during the course of treatment for metastatic breast cancer is presented (status: post-lumpectomy and radiation therapy). Since the onset of vasculitis occurred during the course of therapy for the neoplasm, it was difficult to differentiate between drug-induced vasculitis and paraneoplastic vasculitis. The patient had been exposed to medications including gabapentin, methimazole, trastuzumab, fulvestrant, and letrozole - which could cause endothelial cell toxicity. Drug-induced small vessel vasculitis usually attacks the skin or subcutaneous parts of the skin. In cancer therapy, there have been case reports that hormonal drugs such as estrogen receptor antagonists, aromatase inhibitors, and epidermal growth factor receptor (EGFR) inhibitors can induce cutaneous vasculitis. On the other hand, paraneoplastic syndromes manifested as cutaneous vasculitis have been documented, possibly mediated by unknown immunological mechanisms associated with the tumor such as formation of immune complexes, direct antibody-mediated effects on endothelial cells, or direct effects of tumor cells on the vascular wall. Some patients with drug-induced cutaneous vasculitis have antineutrophil cytoplasm antibodies (ANCA) directed to one or more neutrophil cytoplasm antigens - the most common being granule protein myeloperoxidase (MPO), human leukocyte elastase (HLE), cathepsin G and lactoferrin. Some patients also have antibodies against histones and antiphospholipid. Serologic testing and measurements suggest an influence of therapy on vasculitis, yet the lack of sensitivity and specificity for a biomarker in endothelial injury indicate the need to search and evaluate new markers for improved predictive value of the tests, and to provide guidance in therapy. 相似文献
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BRCA1 alterations with additional defects in DNA damage response genes may confer chemoresistance to BRCA‐like breast cancers treated with neoadjuvant chemotherapy
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Mamoru Takada Shigenori Nagai Masayuki Haruta Ryuichi P. Sugino Katsunori Tozuka Hiroyuki Takei Fumie Ohkubo Kenichi Inoue Masafumi Kurosumi Masaru Miyazaki Aiko Sato‐Otsubo Yusuke Sato Seishi Ogawa Yasuhiko Kaneko 《Genes, chromosomes & cancer》2017,56(5):405-420
The BRCA‐like phenotype is a feature that some sporadic breast cancers share with those occurring in BRCA1 or BRCA2 mutation carriers. As tumors with the phenotype have defects in the DNA damage response pathway, which may increase sensitivity to drugs such as DNA cross‐linking agents and PARP inhibitors, a method to identify this phenotype is important. The prediction of chemoresistance, which frequently develops in these tumors, is also crucial for improving therapy. We examined genomic aberrations and BRCA1 promoter methylation in tumors of 73 breast cancer (20 HR?/HER2? and 53 HR+/HER2?) patients, who received neoadjuvant chemotherapy with anthracycline, cyclophosphamide, and taxane, using SNP array CGH and quantitative PCR. The methylation and/or loss or uniparental disomy (UPD) of BRCA1 (BRCA1 alterations) and the loss or UPD of BRCA2 (BRCA2 alterations) were detected in 27 (37%) and 21 (29%), respectively, of the 73 tumors. Tumors with BRCA1 or BRCA2 alterations were associated with a higher number of genomic aberrations (P < 0.001 and P < 0.001) and higher percentage of TP53 alterations (P < 0.001 and P < 0.001) than those without. Overall survival (OS) rates were similar between patients with or without BRCA1 or BRCA2 alterations. However, when 27 patients with BRCA1‐altered tumors were classified into those with or without the loss or UPD of PALB2 , PAGR1 , RAD51B , FANCM , MLL4 , or ERCC1/2 in tumors, patients with additional defects in DNA damage response genes had worse OS (P = 0.037, 0.045, 0.038, 0.044, 0.041, or 0.019) than those without. These defects may confer chemoresistance and predict poor outcomes in patients with BRCA1‐altered breast cancer. 相似文献
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Kuschel B Auranen A McBride S Novik KL Antoniou A Lipscombe JM Day NE Easton DF Ponder BA Pharoah PD Dunning A 《Human molecular genetics》2002,11(12):1399-1407
We performed genetic association studies in a population-based breast cancer case-control study analysing polymorphisms in genes involved in homologous recombination (NBS1, RAD52, RAD51, XRCC2 and XRCC3) and non-homologous end-joining (KU70/80 and LIG4). These DNA double-strand break repair genes are candidates for breast cancer susceptibility. Genotype results were available for up to 2205 cases and 1826 controls. In the homologous recombination (HR) pathway, genotype frequencies differed between cases and controls for two polymorphisms in XRCC3; T241M (P=0.015) and IVS5 A>G at nt 17893 (P=0.008). Homozygous carriers of M241 were associated with an increased risk [odds ratio (OR) MM versus TT=1.3 (95% confidence interval (CI) 1.1-1.6)], while the rare allele of IVS5A>G was associated with a dominant protective effect [OR AG versus AA=0.8 (0.7-0.9)]. The association of a rare variant in XRCC2 (R188H) was marginally significant [P=0.07; OR HH versus RR=2.6 (1.0-6.7)]. In the non-homologous end-joining (NHEJ) pathway, a polymorphism in LIG4 (T>C at nt 1977) was associated with a decrease in breast cancer risk [P=0.09; OR CC versus TT=0.7 (0.4-1.0)]. No significant association was found for 12 other polymorphisms in the other genes studied. For XRCC3, we found evidence for four common haplotypes and four rarer ones that appear to have arisen by recombination. Two haplotypes, AGC and GGC, were associated with non-significant reductions in breast cancer risk, and the rare GAT haplotype was associated with a significantly increased risk. These data provide some evidence that variants in XRCC2 and LIG4 alter breast cancer risk, together with stronger evidence that variants of XRCC3 are associated with risk. If these results can be confirmed, understanding the functional basis should improve our understanding of the role of DNA repair in breast carcinogenesis. 相似文献
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Germline mutations in DNA repair genes may predict neoadjuvant therapy response in triple negative breast patients
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Laura Spugnesi Michele Gabriele Rosa Scarpitta Mariella Tancredi Luisa Maresca Gaetana Gambino Anita Collavoli Paolo Aretini Ilaria Bertolini Barbara Salvadori Elisabetta Landucci Andrea Fontana Elena Rossetti Manuela Roncella Giuseppe Antonio Naccarato Maria Adelaide Caligo 《Genes, chromosomes & cancer》2016,55(12):915-924
Triple negative breast cancers (TNBCs) represent about 15–20% of all breast cancer cases and are characterized by a complex molecular heterogeneity. Some TNBCs exhibit clinical and pathological properties similar to BRCA‐mutated tumors, without actually bearing a mutation in BRCA genes. This “BRCAness” phenotype may be explained by germline mutations in other genes involved in DNA repair. Although respond to chemotherapy with alkylating agents, they have a high risk of recurrence and progression. Some studies have shown the efficacy of neoadjuvant therapy in TNBC patients with DNA repair defects, but proper biomarkers of DNA repair deficiency are still needed. Here, we investigated if mutations in DNA repair genes may be correlated with anthracyclines/taxanes neoadjuvant therapy response. DNA from 19 TNBC patients undergoing neoadjuvant therapy were subjected to next generation sequencing of a panel of 24 genes in DNA repair and breast cancer predisposition. In this study, 5 of 19 patients (26%) carried a pathogenic mutation in BRCA1, PALB2, RAD51C and two patients carried a probable pathogenic missense variant. Moreover, VUS (Variants of Unknown Significance) in other genes, predicted to be deleterious by in silico tools, were detected in five patients. Germline mutations in DNA repair genes were found to be associated with the group of TNBC patients who responded to therapy. We conclude that a subgroup of TNBC patients have defects in DNA repair genes, other than BRCA1, and such patients respond favourably to neoadjuvant anthracyclines/taxanes therapy. © 2016 Wiley Periodicals, Inc. 相似文献
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Bi‐allelic alterations in DNA repair genes underpin homologous recombination DNA repair defects in breast cancer
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Robert W Mutter Nadeem Riaz Charlotte KY Ng Rob Delsite Salvatore Piscuoglio Marcia Edelweiss Luciano G Martelotto Rita A Sakr Tari A King Dilip D Giri Maria Drobnjak Edi Brogi Ranjit Bindra Giana Bernheim Raymond S Lim Pedro Blecua Alexis Desrichard Dan Higginson Russell Towers Ruomu Jiang William Lee Britta Weigelt Jorge S Reis‐Filho Simon N Powell 《The Journal of pathology》2017,242(2):165-177
Homologous recombination (HR) DNA repair‐deficient (HRD) breast cancers have been shown to be sensitive to DNA repair targeted therapies. Burgeoning evidence suggests that sporadic breast cancers, lacking germline BRCA1/BRCA2 mutations, may also be HRD. We developed a functional ex vivo RAD51‐based test to identify HRD primary breast cancers. An integrated approach examining methylation, gene expression, and whole‐exome sequencing was employed to ascertain the aetiology of HRD. Functional HRD breast cancers displayed genomic features of lack of competent HR, including large‐scale state transitions and specific mutational signatures. Somatic and/or germline genetic alterations resulting in bi‐allelic loss‐of‐function of HR genes underpinned functional HRD in 89% of cases, and were observed in only one of the 15 HR‐proficient samples tested. These findings indicate the importance of a comprehensive genetic assessment of bi‐allelic alterations in the HR pathway to deliver a precision medicine‐based approach to select patients for therapies targeting tumour‐specific DNA repair defects. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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乳腺癌新辅助化疗组织学疗效评价研究 总被引:5,自引:1,他引:5
目的 探讨乳腺癌新辅助化疗后根治标本的组织学疗效评价标准.方法 收集2005年6月至2007年6月乳腺癌新辅助化疗154例档案,其中改良根治术139例,保乳手术15例.化疗结束后4周内实施乳腺根治术.按照Miller and Payne(MP)分级系统的标准规范进行取材、制片和按该系统组织学疗效评价标准进行分级评价,同时与既往应用的肿瘤治疗反应评价系统(既往评价系统)进行比较.对所有病例进行常规随访.应用SPSS 13.0软件进行统计学处理.结果 (1)154例手术标本所获得的组织学疗效评价信息:MP分级系统1级12例(7.8%)、2级33例(21.4%)、3级64例(41.6%)、4级31例(20.1%)、5级14例(9.1%);既往评价系统分别为轻度治疗反应51例(33.1%)、中度治疗反应71例(46.1%)、重度治疗反应32例(20.8%).MP分级系统与既往评价系统各组病例比例之间存在统计学相关(X2=186.660,P<0.01).(2)154例患者中147例获得随访信息(95.5%),随访时间16~38个月;其中14例出现术后复发、远处转移或死亡.MP分级系统5个级别组与患者生存状态均相关(X2=11.612,P=0.020),既往评价系统3个级别组与患者生存状态均无关(X2=0.881,P=0.644).结论 MP分级系统可以用于肿瘤化疗后的组织学疗效评价,与预后相关. 相似文献
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Chang‐Yi Lu Sen‐Yung Hsieh Yen‐Jung Lu Chi‐Sheng Wu Lih‐Chyang Chen Shao‐Jung Lo Cheng‐Tao Wu Min‐Yuan Chou Tim Hui‐Ming Huang Yu‐Sun Chang 《Genes, chromosomes & cancer》2009,48(12):1057-1068
Investigating aberrant DNA methylation in the cancer genome may identify genes that play an important role in tumor progression. In this study, we combined differential methylation hybridization and a CpG microarray platform to characterize methylation profiles and identify novel candidate genes associated with hepatocellular carcinoma (HCC). The genomic DNA of 21 paired adjacent normal and HCC samples was used, and results were analyzed by hierarchical clustering. Twenty‐seven hypermethylated candidates and 38 hypomethylated candidates were obtained. Six candidate genes from the hypermethylated group were validated by combined bisulfite restriction analysis; two genes, human kallikrein 10 gene (KLK10) and oxoglutarate (α‐ketoglutarate) receptor 1 gene (OXGR1), were further analyzed by bisulfite sequencing. The DNA hypermethylation status of KLK10 and OXGR1 were subsequently examined in HCC cell lines and clinical samples using methylation‐specific PCR. In 49 HCC samples, 46 (94%) showed that at least one of these two genes was highly methylated. Moreover, KLK10 and OXGR1 mRNA levels were inversely correlated (r = ?0.435 and ?0.497, P < 0.05) with DNA methylation as examined in paired adjacent normal and tumor samples. Statistical analyses further indicated that KLK10 hypermethylation was significantly associated with cirrhosis (P = 0.042) and HCV infection (P = 0.017) as well as inversely associated with HBV infection (P = 0.023). Furthermore, restoration of KLK10 and OXGR1 expression reduced the ability of anchorage‐independent growth, and sensitized HCC cells to doxorubicin‐ or 5‐fluorouracil‐induced cytotoxicity. Our results suggest that the hypermethylated KLK10 and OXGR1 are frequent in HCC and may be useful as markers for clinical application. © 2009 Wiley‐Liss, Inc. 相似文献
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Yu-Feng Yang Ying-Yang Liao Le-Qun Li Shu-Rui Xie Yan-Fang Xie Ning-Fu Peng 《Pathology, research and practice》2013
Previous studies have reported conflicting results regarding the impact of neoadjuvant chemotherapy (NAC) on estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status in breast cancer. Our aim was to investigate whether NAC induces some selective change in the breast biomarkers. 相似文献
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Zhao YF Zhang YG Tian XX Juan Du Jie Zheng 《International journal of surgical pathology》2007,15(3):242-251
In this study, we examined aberrant methylation of the E-cadherin, estrogen receptor, RB1 , p16, p15, p14, and MGMT genes by the methylation-specific polymerase chain reaction method in 101 gastric carcinomas. Hypermethylation was detected in E-cadherin, estrogen receptor, RB1, p16, p14, p15, and MGMT at the rates of 27.7%, 44.6%, 44.6%, 30.7%, 19.2%, 7.7%, and 6.9%, respectively. A total of 82.2% cases had methylation in at least 1 of these genes, and 44.6% had methylation in 2 or more of these genes. Methylation of RB1 was associated with absence of lymph node metastasis. Methylation of estrogen receptor was associated with age and tumor location. Methylation of E-cadherin coincided with methylation of p16 or estrogen receptor. Moreover, loss of p16 protein was strongly associated with its gene methylation. This study indicates that aberrant methylation of multiple genes is involved in gastric carcinogenesis. 相似文献
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新辅助化疗乳腺癌病理标本的处理对策及报告规范 总被引:1,自引:0,他引:1
新辅助化疗(neoadjuvant clhemotherapy)是指在进行手术治疗前对肿瘤患者进行化疗的一种治疗方法.1973年,米兰癌症中心的研究者首先采用新辅助化疗对失去手术机会的乳腺癌患者进行治疗,以期缩小肿块从而使患者有机会接受手术或放射治疗 [1].与常规化疗相比,新辅助化疗具有以下一些特点:(1)约80%的患者化疗后肿块缩小,原本失去手术机会的乳腺癌患者可重获手术机会;一些原本需施行乳房全切除的患者可进行保乳治疗,虽然这些患者的局部复发率可能升高,但其存活率与先手术后化疗的患者相当. 相似文献
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乳腺癌新辅助化疗的临床意义和病理学评价 总被引:2,自引:0,他引:2
一、乳腺癌新辅助化疗的定义
自1990年以来,国内肿瘤外科医师借鉴国外乳腺癌治疗的先进经验,开始对可手术的乳腺癌治疗方案进行改革,在术前先行化疗,再施行改良根治术,这种新的治疗模式大大减少了乳腺癌根治术的使用,也降低了手术对患者身体的创伤程度,提高了患者的生活质量. 相似文献
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目的:探讨新辅助化疗对乳腺癌组织病理学及免疫组织化学的影响.方法:观察术前经粗针吸活检(core needle biopsy,CNB)确诊的80例乳腺癌新辅助化疗后肿瘤标本的组织病理学改变,并分析其手术前后ER、PR、HER2等免疫表型的变化.结果:新辅助化疗对乳腺癌总显效率为67.5%,手术前后肿瘤组织的ER、PR、HER2总阳性表达率差异无显著性(P>0.05),但ER、PR、HER2均出现较高的不符合率,依次为45.0%、37.5%、12.5%.结论:新辅助化疗能有效地作用于肿瘤组织,并能帮助寻找术后有针对性的化疗方案;但对ER、PR、HER2等免疫标记有较大影响,可能会对术后选择内分泌治疗及靶向治疗造成不确定因素. 相似文献
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Aberrant patterns of DNA methylation, chromatin formation and gene expression in cancer 总被引:32,自引:0,他引:32
Baylin SB Esteller M Rountree MR Bachman KE Schuebel K Herman JG 《Human molecular genetics》2001,10(7):687-692
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Qi-Xing Tan Qing-Hong Qin Wei-Ping Yang Bin Lian Chang-Yuan Wei 《International journal of clinical and experimental pathology》2014,7(7):4086-4094
Background: To investigate the prognostic value of hormone receptor (HR) status conversion after neoadjuvant chemotherapy (NAC) in patients with primary breast cancer. Methods: 267 stage II-III breast cancer patients treated with NAC who had residual disease in the breast after NAC were retrospectively studied. The patients were divided into four groups based on the HR status: Group A, patients with HR-positive both before and after NAC; Group B, patients with HR status positive-to-negative change; Group C, patients with HR status negative-to-positive change; Group D, patients with HR-negative both before and after NAC. Patients with positive HR status (regardless of before or after NAC) were treated with adjuvant endocrine therapy, and a survival analysis was performed. Results: In total, 15.7% of patients had HR status change after NAC. progression-free survival (PFS) in Group A was similar to that in Group C (hazard ratio, 1.16; P = 0.652), but that in Group B was significantly lesser than that in Group A (hazard ratio, 6.88; P = 0.001), and that in Group C was significantly longer than that in Group D (hazard ratio, 6.88; P = 0.001). A similar pattern of results was obtained for overall survival (OS). Conclusions: The switch of HR status after NAC is remarkable for breast cancer. An HR switch may identify patients who would benefit from adjuvant endocrine therapy and impact the long-term outcome. 相似文献
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99mTc-MIBI显像可预测乳腺癌新辅助化疗的反应性 总被引:2,自引:0,他引:2
目的探讨根据乳腺^99mTc-MIBI显像的表现,预测乳腺癌新辅助化疗反应性的临床价值。方法对43例Ⅱ、Ⅲ期的乳腺癌患者,手术前行乳腺癌^99mTc-甲氧基异丁基异睛(^99mTc-MIBI)早期显像和延迟显像。对显像阳性的肿块计算感兴趣区与对侧正常相应部位放射性计数比值,以早期摄取比值(EUR)和延迟摄取比值(DUR)计算滞留指数(RI),之后行2周期的FAC方案化疗。结果在^99mTc-MIBI显像RI≥0组,化疗的有效率为83.3%(25/30),在RI〈0组化疗的有效率23.1%(3/13),两组间差异有显著的统计学意义(P〈0.01)。结论乳腺^99mTc-MIBI显像可以预测新辅助化疗的反应性,指导个性化化疗方案的选择。 相似文献
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Genistein inhibits DNA methylation and increases expression of tumor suppressor genes in human breast cancer cells
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Ling‐Yun Zou Qian‐Yong Zhang Yong Zhou Hui Chang Long Yi Jun‐Dong Zhu Man‐Tian Mi 《Genes, chromosomes & cancer》2014,53(5):422-431
It has been previously demonstrated that genistein exhibits anticancer activity against breast cancer. However, the precise mechanisms underlying the anticancer effect of genistein, in particular the epigenetic basis, remain unclear. In this study, we investigated whether genistein could modulate the DNA methylation status and expression of cancer‐related genes in breast cancer cells. We treated MCF‐7 and MDA‐MB‐231 human breast cancer cells with genistein in vitro. We found that genistein decreased the levels of global DNA methylation, DNA methyltransferase (DNMT) activity and expression of DNMT1. Yet, the expression of DNMT3A and DNMT3B showed no significant change. Using molecular modeling, we observed that genistein might directly interact with the catalytic domain of DNMT1, thus competitively inhibiting the binding of hemimethylated DNA to the catalytic domain of DNMT1. Furthermore, genistein decreased DNA methylation in the promoter region of multiple tumor suppressor genes (TSGs) such as ataxia telangiectasia mutated (ATM), adenomatous polyposis coli (APC), phosphatase and tensin homolog (PTEN), mammary serpin peptidase inhibitor (SERPINB5), and increased the mRNA expression of these genes. However, we detected no significant changes in the DNA methylation status or mRNA expression of stratifin (SFN). These results suggest that the anticancer effect of genistein on breast cancer may be partly due to its ability to demethylate and reactivate methylation‐silenced TSGs through direct interaction with the DNMT1 catalytic domain and inhibition of DNMT1 expression. © 2014 Wiley Periodicals, Inc. 相似文献
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Yamaguchi R Tanaka M Yano A Tse GM Yamaguchi M Koura K Kanomata N Kawaguchi A Akiba J Naito Y Ohshima K Yano H 《Human pathology》2012,43(10):1688-1694
Neoadjuvant chemotherapy or preoperative systemic therapy is increasingly considered for patients with operable breast cancer. Patients with breast cancer were examined for pathologic factors predictive of response to neoadjuvant chemotherapy, using an anthracycline-based regimen. For clinical histomorphology and biomarkers, factors were compared among 16 pathologically complete responses and 52 nonpathologically complete responses, using univariate analysis and multivariate regression analysis of principal components, using preneoadjuvant chemotherapy needle biopsy samples as follows: degree of tumor-infiltrating lymphocytes, histologic grade, biology-based tumor type (hormone receptors and HER2 [human epidermal growth factor receptor type 2]), age, clinical TNM stage, and TNM staging. In univariate analysis, high tumor-infiltrating lymphocyte, high histologic grade, and hormone receptors(-)/HER2(+) were significantly associated with pathologically complete responses (93.7%, P < .0001; 81.3%, P = .0206; 43.7%, P = .014, respectively). In multivariate principal component regression analysis, high tumor-infiltrating lymphocytes were the best independent predictor for pathologically complete responses (odds ratio, 4.7; confidence interval, 2.2-10.06; P < .0001). Among tumor-infiltrating lymphocytes and biology-based tumor types, patients with high tumor-infiltrating lymphocytes had pathologically complete responses more than nonpathologically complete responses, especially in the hormone receptors(-)/HER2(+) group. Among high tumor-infiltrating lymphocyte cases, T lymphocytes showed more predominant tendency than B lymphocytes in the pathologically complete responses cases, compared with nonpathologically complete responses cases. These findings indicate that high tumor-infiltrating lymphocytes are important predictors of pathologically complete responses to neoadjuvant chemotherapy, especially in the hormone receptors(-)/HER2(+) group. 相似文献
20.
Promoter methylation status of the DNA repair genes hMLH1 and MGMT in gastric carcinoma and metaplastic mucosa. 总被引:6,自引:0,他引:6
Hypermethylation of CpG islands in the promoter region is associated with the silencing of a variety of tumor suppressor genes. DNA repair genes human Mut L homologue 1 (hMLH1) and O(6)-methylguanine-DNA methyltransferase (MGMT) have been shown to be hypermethylated in certain carcinomas. We studied DNA methylation of CpG islands in hMLH1 and MGMT in 50 gastric carcinomas and 10 intestinal metaplastic mucosa samples. We analyzed the methylation status of hMLH1 and MGMT using methylation-specific polymerase chain reaction and DNA sequencing analysis. We measured protein levels of hMLH1 using Western blot and immunohistochemical analysis. CpG island hypermethylation of hMLH1 and MGMT was detected in 11 (22%) and 8 (16%) of the 50 gastric tumors, respectively. Hypermethylation of the promoter was more common in intestinal-type gastric carcinomas than in poorly diffuse-type gastric carcinomas (p = 0.016 and 0.021, respectively; Fisher's exact test). However, hMLH1 promoter hypermethylation did not coincide with MGMT promoter hypermethylation except in 1 patient. Hypermethylation of the hMLH1 promoter but not the MGMT promoter occurred in intestinal metaplastic mucosae. Immunohistochemical analysis revealed a corresponding reduction in hMLH1 protein expression in some of the intestinal metaplastic mucosae. Our results suggest that at least two types of promoter methylation participate in the development of gastric carcinoma. Tumor-specific promoter hypermethylation of hMLH1 may be an early event in carcinogenesis in the stomach. 相似文献