bcl-2与乳腺癌耐药蛋白基因在弥漫大B细胞淋巴瘤中表达的意义

目的 研究bcl-2和乳腺癌耐药蛋白(BCRP)基因在非霍奇金淋巴瘤(NHL)中的表达及其相关性.方法 对初治弥漫大B细胞淋巴瘤(DLBCL)患者(40例)淋巴结组织液,采用流式细胞术(FCM)及反转录聚合酶链反应(RT-PCR)技术定量检测其BCRP mRNA的表达,同时将患者标本常规石蜡包埋、HE染色和链霉菌素牛物素技术(LSAB)免疫组织化学法标记bcl-2蛋白表达.结果 40例DLBLC患者的bcl-2与BCRP的阳性表达率分别为60.0%(24/40),37.5%(15/40),不同临床分期的DLBCL患者,BCRP阳性表达率差异有统计学意义(x2=6.0606,P<0.05).bcl-2、BCRP表达阳性组有效率低于表达阴性组,差异有统计学意义(x2=5.7618,P<0.05;x2=6.5541,P<0.05);bcl-2和BCRP表达均阳性与均阴性患者的疗效比较,差异无统计学意义(x2=2.0263,P>0.05).结论 BCRP可能在DLBCL的原发多药耐药中发挥重要作用,并有助于化疗疗效的评估及提示疾病转归;bcl-2在DLBCL中的表达对肿瘤恶性程度及预后的判断均有一定意义;联合检测bcl-2和BCRP基因对评价DLBCL预后有较大意义.     

Choi和Hans分型在弥漫大B细胞淋巴瘤预后评价中的意义

目的 探讨Choi和Hans分型在弥漫大B细胞淋巴瘤(DLBCL)预后评价中的意义.方法 收集山西省肿瘤医院病理科有详细随访资料的DLBCL 99例,用免疫组织化学EnVision法检测bcl-2、bel-6、CD10、FOXP1、GCET1、MUM-1的表达情况.根据Choi和Hans两种分类法分别将所有病例分型.其中35例应用荧光原位杂交技术检测bcl-6基因重排情况.结果 按Hans分类法生发中心B细胞(GCB)型21例,非GCB(nonGCB)型78例;按Choi分类法GCB型23例,nonGCB型76例.GCB型生存率明显优于nonGCB型,差异有统计学意义(P=0.000).FOXP1蛋白阳性表达与预后呈负相关(P=0.011),GCET1阳性表达则与预后呈正相关(P=0.027).在35例DLBCL患者中.bcl-6基因重排阳性高发于nonGCB型患者,bcl-6基因重排与bcl-6蛋白的表达没有明显相关性.结论 Choi和Hans两种分类法免疫分型GCB型预后都优于nonGCB型.bcl-6、FOXP1、GCET1的表达与预后有相关性.Choi及Hans分类法对DLBCL的免疫分型、临床预后估计均有应用价值.     

PTEN、MLL基因在T淋巴母细胞淋巴瘤/白血病的表达及其意义

目的 分析肿瘤抑制基因PTEN、混合系白血病(MLL)基因等在T淋巴母细胞淋巴瘤/白血病(T-LBL/ALL)的表达及意义.方法 选用76例T-LBL/ALl患者淋巴结存档蜡块,应用免疫组织化学EnVision法进行 PTEN标记,用20例反应性增生淋巴结标本作正常对照.并用荧光原位杂交(FISH)技术检测MLL基因所在1 1q23染色体的断裂和扩增情况.结果 76例T-LBL/ALL中,PTEN的表达率为64.47%(49/76),低于淋巴结反应性增生的100%(20/20)(λ2=19.220,P＜0.05).PTEN表达与临床分期、Ki-67、乳酸脱氢酶(LDH)呈负相关(P＜0.05).76例T-LBL/ALL中,MLL基因发生1 1q23染色体断裂13例(17.11%),扩增18例(23.68%).MLL基因断裂组总体生存率(25.0%)低于非断裂组(43.6%)(λ2=11.357,P＜0.05).MLL基因扩增组总体生存率(17.1%)低于非扩增组(42.7%)(λ2=4.533,P＜0.05).结论 抑癌基因PTEN表达降低在T-LBL/ALL的发生发展中可能具有重要作用.MLL基因发生染色体1 1q23断裂和扩增有助于对T-LBL/ALL预后的判断,发生MLL基因断裂或扩增的T-LBL/ALL预后较差,提示MLL基因断裂或扩增可能为T-LBL/ALL的一种分子亚型.     

CD20在成年人急性B淋巴细胞白血病中的表达及其临床意义

目的 检测CD20在成年人急性B淋巴细胞白血病(B-ALL)的表达,探讨其与临床特点的相关性.方法 回顾性总结分析96例成年B-ALL患者CD20表达情况,结合其临床特性和治疗转归进行分析.结果 96例成年B-ALL患者中,CD20阳性29例(30.20%),CD20阴性67例(69.79%).CD20阳性组与阴性组男女比分别为1.42∶1和1.79∶1(x2=0.27,P＞0.05),中位年龄分别为28岁与23岁,肝脾及淋巴结浸润比例分别为44.83%和41.38%、40.30%和35.82%,髓系抗原表达比例分别为51.72%与56.72%,Ph染色体和bcr-abl融合基因阳性比例分别为24.14%与28.36%,4周内完全缓解率分别为73.08%与68.85%,差异均无统计学意义(P值均＞0.05).在复发率和3年总体生存率上,CD20阳性组分别为54.55%与14.80%,CD20阴性组分别为29.63%与37.30%,两组间差异有统计学意义(x2=0.42,x2=5.31;P值均＜0.05).结论 CD20在成年人B-ALL表达与临床特点无相关性,但对判断患者的预后有一定的指导意义.     

儿童侵袭性成熟B细胞淋巴瘤的临床病理学及分子遗传学特点

目的 分析总结中国儿童各类型侵袭性成熟B细胞淋巴瘤的临床病理学及分子遗传学特点,为其诊断的标准化提供依据.方法 收集97例儿童侵袭性成熟B细胞淋巴瘤石蜡包埋组织标本,包括伯基特淋巴瘤(BL)81例、弥漫大B细胞淋巴瘤(DLBCL)8例、介于BL和DLBCL间的不能分类的B细胞淋巴瘤(BL/DLBCL)8例,利用免疫组织化学技术和间期荧光原位杂交(FISH)技术检测其免疫表型和分子遗传学特征.结果 BL的bcl-2和MUM1的阳性率分别为3%(2/66)和17%(12/71),DLBCL分别为50%(4/8)和63%(5/8),BL/DLBCL分别为50%(4/8)和63%(5/8).BL、DLBCL和BL/DLBCL的Ki-67平均值分别为(93±4.4)%、(83±14.3)%和(80±11.5)%.BL、DLBCL和BL/DLBCL的c-myc基因易位的比例分别为98%(79/81)、38%(3/8)和50%(4/8).38%(3/8)的DLBCL和25%(2/8)的BL/DLBCL存在bcl-6基因的多拷贝,BL与DLBCL之间、BL与BL/DLBCL之间bcl-2、MUM1和Ki-67平均值的差异及c-myc基因易位和bcl-6基因多拷贝的差异均有统计学意义(均P＜0.05).结论 儿童侵袭性成熟B细胞淋巴瘤的诊断和分型需要综合分析形态学、免疫表型和分子遗传学特征.儿童BL/DLBCL可能是DLBCL的一个亚型.CD10+、bcl-6+、bcl-2-、Ki-67＞90%、伴有IGH/c-myc重排、不伴有bcl-2和bcl-6重排时,支持BL的诊断;bcl-2+、Ki-67为50%～90%,同时伴有bcl-6基因的多拷贝时,支持DLBCL或BL/DLBCL的诊断.     

P53突变蛋白表达对弥漫大B细胞淋巴瘤预后的预测作用

目的 探讨p53突变蛋白表达对弥漫大B细胞淋巴瘤(DLBCL)预后的预测作用,指导个体化治疗.方法 随机选择初治DLBCL患者62例,应用免疫组织化学方法检测p53突变蛋白和CD10、bcl_6、MUM1的表达,分析p53突变蛋白表达与患者临床特征、分子分型以及预后的关系.结果 48.4%(30/62)的患者表达p53突变蛋白.p53突变蛋白表达与初始治疗反应有关(x2=20.365,P=0.040),阳性组的完全缓解率为33.3%(10/30),阴性组为59.4%(19/21);与分子分型有关(x2=31.023,P=0.021),阳性组非生发中心型比例显著高于阴性组,分别为83.3%和56.2%;与其他临床特征无关.多因素生存分析显示p53突变蛋白表达是独立的预后预测因子,阳性组的无进展生存期和中位生存期均短于阴性组(x2=36.784,P=0.005和x2=35.276,P=0.006).结论 p53突变蛋白表达是DLBCL独立的不良预后因子,能够用来指导个体化治疗.     

荧光原位杂交检测乳腺癌人表皮生长因子受体2基因扩增及与临床病理特征的关系

目的:探讨荧光原位杂交法(fluorescence in situ hybridization,HSH)及免疫组织化学法(immunohistochemistry,IHC)检测乳腺癌人表皮生长因子受体2(human epidermal growth factor receptor2,HER-2)的一致性,及HER-2基因扩增与乳腺癌临床病理特征的关系.方法:对北京大学第三医院病理科2008年1月至10月的乳腺浸润性导管癌病例中选取的41例进行HER-2基因扩增的FISH检测和蛋白表达的IHC检测,并对HER-2基因扩增与雌激素受体(estrogen receptor,ER)、组织学分级、癌周脉管内癌栓、腋窝淋巴结转移的关系进行统计学分析.结果:41例乳腺浸润性导管癌中,HER-2基因扩增患者15例,为IHC检测+++者8例,++者6例,+者1例,阴性者0例,分别占IHC+++、++、+及阴性者病例总数的88.89%(8/9)、42.68%(6/14)、8.33%(1/12)及0%(0/6).HER-2基因扩增率在不同组织学分级的乳腺浸润性导管癌中差异无统计学意义(P=0.095).HER-2基因扩增率在ER阴性及弱阳性(+)组高于ER强阳性(++或+++)组(P=0.018),可见脉管内癌栓组高于未见脉管内癌栓组(P=0.000),同侧腋窝淋巴结有转移组高于腋窝淋巴结无转移组(P=0.025).结论:FISH技术可较稳定地应用于乳腺癌HER-2基因扩增的检测,IHC++的患者需进一步行FISH检测;HER-2基因扩增与ER表达呈负相关,与癌周脉管内癌栓、腋窝淋巴结转移呈正相关.     

弥漫大B细胞淋巴瘤细胞耐药的研究进展

弥漫大B细胞淋巴瘤(DLBCL)化疗耐药的主要原因是细胞耐药.研究表明DLBCL细胞耐药与耐药基因及其耐药相关蛋白、细胞因子、黏附分子有关,并在造血微环境中通过信号转导介导细胞耐药.     

Cyclin D1和bcl-2在B细胞淋巴瘤中的表达及其在鉴别诊断中的意义

B细胞淋巴瘤根据免疫表型可分为不同亚型,且不同亚型侵袭度不同,预后也有很大差异.Cyclin D1是已被证实与肿瘤有最直接关系的细胞周期蛋白,在大多B细胞淋巴瘤[套细胞淋巴瘤(MCL)、慢性淋巴细胞白血病(CLL)、边缘区淋巴瘤(MZL)、弥漫大B细胞淋巴瘤(DLBCL)等」中均有表达.多数B细胞淋巴瘤[滤泡性淋巴瘤(FL)、DLBCL等]都能可见易位活化的bcl-2表达增强.Cyclin D1及bcl-2作为B细胞淋巴瘤重要的细胞周期蛋白及抗凋亡基因,在淋巴瘤的鉴别诊断中起重要作用,其检测及检测手段的灵敏度和特异度具有重要的临床价值.     

系统性间变性大细胞淋巴瘤骨髓累及的临床病理学研究

目的 探讨系统性间变性大细胞淋巴瘤(S-ALCL)骨髓累及的临床病理学特点、免疫学表型及临床生物学行为.方法 回顾性分析34例S-ALCL病例资料,进行骨髓活检(19例)或涂片(15例).其中ALK(+)24例,ALK(-)10例.HE染色、免疫组织化学染色观察病理形态及免疫表型,原位杂交法检测EB病毒.结果 6例(17.6%)S-ALCL存在骨髓累及,均经骨髓活检标本确定,15例患者骨髓涂片中均未见肿瘤累及.ALK(+)ALCL和ALK(-)ALCL骨髓累及的发生率分别为16.7%(4/24)和20.0%(2/10),差异无统计学意义(P=0.3555).与无骨髓累及病例比较,骨髓累及病例的年龄、性别分布差异无统计学意义(P值分别为0.8089和0.3085).骨髓累及者肿瘤细胞以间质性分布为主[83.3%(5/6)].生存分析统计提示伴有骨髓累及的患者预后明显差于无骨髓累及者(P=0.0407).结论 S-ALCL骨髓累及发生率低,与患者的发病年龄、性别及ALK蛋白的表达无相关性.伴有骨髓累及的S-ALCL患者临床预后差,骨髓活检在判断S-ALCL预后中有重要意义.     

The 9p21 region in bladder cancer cell lines: large homozygous deletion inactivate the CDKN2, CDKN2B and MTAP genes

Homozygous and hemizygous deletions of 9p21 are the earliest and most common genetic alteration in bladder cancer. The identification of two cell cycle regulators, CDKN2 and CDKN2B, that map to the common region of deletion has prompted the hypothesis that they are critical tumor suppressor genes in this malignancy. However, controversy as to whether these genes are the only or even the most important target in bladder cancer oncogenesis remains. To more clearly determine the effect of these 9p21 alterations, we mapped the homozygous deletions and performed a detailed mutational and expression analysis for CDKN2, CDKN2B and a closely linked gene, methylthioadenoside phosphorylase (MTAP), in 16 established bladder cancer cell lines. Nine of the 16 lines exhibit large (30 to > 2000 kb) homozygous deletions on 9p21. All deletions include at least one exon of CDKN2, eight of nine include CDKN2B, and six of nine include MTAP. MTAP function correlates with the genomic deletions. SSCP and sequence analysis does not reveal any inactivating point mutations of CDKN2 or of CDKN2B in any of the cell lines without homozygous deletions, and all express the CDKN2 and the CDKN2B mRNA as well as the encoded p16 protein. The p16 protein levels vary widely and are correlated with absent pRb expression. We conclude that the 9p21 deletions in bladder cancer usually inactivate the CDKN2. CDKN2B, and MTAP genes but that CDKN2 is the most common target. Other mechanisms for inactivating this gene in bladder cancer appear to be uncommon.     

Screening of germline mutations in the CDKN2A and CDKN2B genes in Swedish families with hereditary cutaneous melanoma

BACKGROUND: Approximately 10% of human cutaneous melanomas occur in families in which several members are affected. The familial predisposition to this disease is often associated with dysplastic nevus syndrome, a condition in which afflicted family members have multiple dysplastic nevi (atypical moles). The chromosome region 9p21 and markers on chromosomes 1p and 6p have been linked to melanoma susceptibility. The tumor suppressor genes CDKN2A and CDKN2B have been mapped to the 9p21 region, and genetic analyses have revealed the presence of germline CDKN2A alterations in melanoma families. The reported frequencies of such alterations, however, vary among these families. PURPOSE: The present investigation was carried out to determine the frequencies of CDKN2A and CDKN2B germline gene mutations among members in a population-based cohort of Swedish melanoma families (i.e., melanoma kindreds). METHODS: DNA was prepared from blood samples obtained from 181 individuals belonging to 100 melanoma kindreds. The polymerase chain reaction (PCR) technique, followed by single-strand conformation polymorphism (SSCP) and nucleotide sequence analyses, were used to identify the types and frequencies of mutations in exons 1, 1beta, 2, and 3 of the CDKN2A gene and in exons 1 and 2 of the CDKN2B gene. RESULTS: CDKN2A gene aberrations were independently identified by both SSCP and nucleotide-sequence analyses. Nucleotide-sequence analysis identified a single point mutation leading to a substitution of leucine for proline in codon 48 of exon 1 in a family with a history of melanoma and several other cancers. A second abnormality, leading to an insertion of an extra arginine residue at codon number 113 of exon 2, was seen in four separate families. The CDKN2A exon-3 coding region had the wild-type sequence in all samples. No germline mutations were found in the alternative exon 1beta of the CDKN2A gene or in exons 1 and 2 of the CDKN2B gene. CONCLUSIONS: The present investigation demonstrates that CDKN2A germline gene mutations were observed in 7.8% of the 64 Swedish melanoma kindreds that each included at least two first-degree relatives with melanoma and dysplastic nevus syndrome. No CDKN2A exon 1beta or CDKN2B mutations were identified. The critical genes responsible for the inheritance of a susceptibility to develop melanoma among family members in this population have yet to be identified.     

Growth arrest and suppression of tumorigenicity of bladder-carcinoma cell lines induced by the P16/CDKN2 (p16INK4A, MTS1) gene and other loci on human chromosome 9

Wild-type P16/CDKN2 (p16INK4A, MTS1) cDNA, directed by the cytomegalovirus (CMV) immediate early promoter, was transfected into RT4 and RT112 bladder-carcinoma cell lines bearing a mutated endogenous P16/CDKN2 gene and lacking endogenous P16/CDKN2 respectively. In both cases, only transfected clones with rearranged exogenous P16/CDKN2 cDNA could be grown and propagated in cell culture. This result is reminiscent of transfection of wild-type p53 into cells with a deleted or mutated endogenous gene and suggests that P16/CDKN2, over-expressed under control of the strong CMV promoter, induces growth arrest in RT4 and RT112 cells. Transfer of human chromosome 9 to RT4 cells produced RT4/H9 hybrid clones retaining the P16/CDKN2 gene, since in RT4/H9 cell clones P16/CDKN2-gene expression is modulated by the physiological control of chromosomal regulatory sequence. All the RT4/H9 clones lost the entire chromosome 9, except clone 4 and clone 5, which maintained a deleted and an intact chromosome 9 respectively. Loss of several loci in 9p21, including P16/CDKN2, in tumors induced in nude mice by clone 4 and clone 5 suggests that P16/CDKN2 or other genes in 9p21 suppress tumorigenicity in bladder-carcinoma cells. Tumors induced by clone 4 and clone 5 show loss of markers in 9q. The regions 9q22.3, 9q32-33 and 9q34.2, which were maintained in the 2 clones and lost in their derived tumors, may contain tumor-suppressor genes relevant in bladder carcinoma. The results of this study suggest that the P16/CDKN2 gene controls growth of bladder-carcinoma cells when it is over-expressed, and may be involved in the development of bladder carcinoma, but other genes in 9p21 and 9q may participate in bladder-cancer progression.     

Homozygous deletions of methylthioadenosine phosphorylase (MTAP) are more frequent than p16INK4A (CDKN2) homozygous deletions in primary non-small cell lung cancers (NSCLC)

Homozygous deletions of the tumor suppressor gene p16INK4A and deficiency of methylthioadenosine phosphorylase (MTAP), both located on chromosome 9p21, have been independently reported in non-small cell lung cancer (NSCLC). To determine the frequency of co-deletion of these two genes, we investigated 50 samples of primary NSCLC using a quantitative PCR-ELISA. All specimens were fixed in formalin, paraffin embedded and stored until assayed. Histologic subtypes included 25 adenocarcinomas (50%), 21 squamous cell carcinomas (42%) and four large cell carcinomas (8%). Homozygous deletions of MTAP exon 8 could be detected in 19 of 50 NSCLC samples (38%). Adenocarcinoma (11 of 25, 44%) showed a higher deletion frequency than squamous cell carcinoma (six of 21, 29%). In contrast, homozygous p16INK4A deletions were detected in only nine of 50 (18%) samples using specific primers for p16INK4A exon 1alpha. No difference between the histological subtypes and p16INK4A deletion frequency was observed. We further investigated the ten samples with MTAP deletions but intact p16INK4A exon 1alpha with primers specific for p16INK4A exon 3, the exon nearest to MTAP exon 8. Interestingly, none of the ten samples had deletion of the p16INK4A exon 3 coding region. Fine mapping analysis performed in ten samples showed a frequent breakpoint between MTAP exon 4 and exon 5. In addition, p16 protein expression could not be detected in five out of six samples with intact p16 but deleted MTAP locus. These data show a high frequency of homozygous MTAP deletions in NSCLC which is associated with detectable co-deletion of p16INK4A in only half of the cases. This result suggests the existence either of another tumor suppressor gene telomeric of p16INK4A or of deletions involving 3'-untranslated (3'-UTR) regulatory regions of p16INK4A that can interfere with its expression or function.     

MUM1/IRF4在滤泡性淋巴瘤中的表达及其临床病理意义

目的 探讨MUM1/IRF4在滤泡性淋巴瘤(FL)中的表达情况及临床病理意义.方法 对96例FL患者标本进行MUM1、CD10、bcl-2、bcl-6、Ki-67免疫组织化学染色,并与患者的临床资料和病理学特征比较.结果 MUM1在96例FL中总的阳性率为59.2%(58/96),其中1～2级组阳性率为36.2%(19/51),3级组阳性率为86.4%(39/45)(x2=24.406,P<0.001).68.9%伴有弥漫成分的FL患者MUM1阳性(x2=8.161,P=0.004).MUM1和CD10的表达呈负相关,83.3%的CD10阴性病例表达MUM1(x1=12.649,P<0.001).MUM1阳性者核分裂和Ki-67标记指数高于MUM1阴性者(t=-3.852、t=-4.610,P<0.001).结论 MUM1可作为FL分型的标志物.MUM1阳性的FL可能为类似非生发中心B细胞分化特征的高度恶性淋巴瘤.     

CDKN2A mutations in multiple primary melanomas

BACKGROUND: Germ-line mutations in the CDKN2A tumor-suppressor gene (also known as p16, p16INK4a, and MTS1) have been linked to the development of melanoma in some families with inherited melanoma. Whether mutations in CDKN2A confer a predisposition to sporadic (nonfamilial) melanoma is not known. In some patients with sporadic melanoma, one or more additional primary lesions develop, suggesting that some of these patients have an underlying genetic susceptibility to the cancer. We hypothesized that this predisposition might be due to germ-line CDKN2A mutations. METHODS: We used the polymerase chain reaction, single-strand conformation polymorphism analysis, and direct DNA sequencing to identify germ-line mutations in the CDKN2A gene in patients with multiple primary melanomas who did not have family histories of the disease. A quantitative yeast two-hybrid assay was used to evaluate the functional importance of the CDKN2A variants. RESULTS: Of 33 patients with multiple primary melanomas, 5 (15 percent; 95 percent confidence interval, 4 percent to 27 percent) had germ-line CDKN2A mutations. These included a 24-bp insertion at the 5' end of the coding sequence, three missense mutations (Arg24Pro, Met53Ile, and Ser56Ile), and a 2-bp deletion at position 307 to 308 (resulting in a truncated CDKN2A protein). In three families, CDKN2A mutations identical to those in the probands were found in other family members. In two families with mutations, we uncovered previously unknown evidence of family histories of melanoma. CONCLUSIONS: Some patients with multiple primary melanomas but without family histories of the disease have germ-line mutations of the CDKN2A gene. The presence of multiple primary melanomas may signal a genetic susceptibility to melanoma not only in the index patient but also in family members, who may benefit from melanoma-surveillance programs.     

Alterations of CDKN2 gene structure in childhood acute lymphoblastic leukemia: mutations of CDKN2 are observed preferentially in T lineage

We analyzed homozygous deletions and mutations of the CDKN2(p16(INK4A)/MTS1) gene, using polymerase chain reaction and Southern blot analysis, in 120 children with acute lymphoblastic leukemia (ALL). Homozygous deletion was found in 17 of 89 (19%) precursor B-ALL patients, in 11 of 24 (46%) T-ALL patients, and in 0 of 7 other phenotype ALL patients. After excluding 28 (23%) patients who showed a homozygous deletion of CDKN2, we found that three patients (3%) had mutation at exon 2 of CDKN2 using PCR-SSCP and sequencing strategy. One had a CGA to TGA nonsense mutation (Arg to stop) at codon 72, one had a 1-bp deletion at codon 117, and the third had a 2-bp deletion at codon 70, resulting in frameshifts in the two latter patients. All three of these patients were T phenotype ALL, and the incidence of mutation in the 24 T-ALL patients examined was 13%. In contrast, no mutation was detected in the remaining patients with precursor-B or other type ALL (0/96). Our results suggest that mutational inactivation of the CDKN2 gene may contribute to the leukemogenic growth, especially in some patients with T-ALL.