c-erbB-2/c-erbA co-amplification indicative of lymph node metastasis, and c-myc amplification of high tumour grade, in human breast carcinoma

A panel of 73 samples, including 52 primary breast carcinomas, 10 normal breast tissues and 11 axillary lymph nodes, has been analysed for the presence of amplifications and gross structural alterations, in the oncogenes c-erbB-2, c-erbA, c-myc, N-myc, c-mos and c-Ha-ras. The tumours were also classified, graded and staged histopathologically and their DNA ploidy (42 samples) was determined by flow cytometry. Three breast cancer cell lines (MCF7, ZR-75-1 and T47D) were also included in the study. Amplification of c-erbB-2 was detected in 28% of the tumours, of which 91% had an increased steady-state level of c-erbB-2 mRNA. Amplification of c-erbA was found in 23% of tumours and was always associated with the amplification of c-erbB-2. Ten out of 12 (83%) tumours which had c-erbB-2 and c-erbA co-amplification had metastasised to axillary lymph nodes (P less than 0.006). However, the human thymidine kinase gene, which is present at the same chromosomal location as these two oncogenes (17q21-22), was amplified in only tw tumours. Amplification of c-myc was detected in 21% of the tumours studied, of which 82% (P less than 0.005) were of histopathological grade 3 and none were of grade 1. Flow cytometry showed that 90% (P less than 0.01) of the analysed tumours with c-erbB-2 and c-erbA co-amplification, and 70% (P less than 0.1) of those with c-myc amplification were DNA aneuploid. This study demonstrates the potential value of c-myc amplification in the assessment of the tumour grade, rather than metastatic potential; and of the co-amplification of c-erbB-2 and c-erbA as a strong indicator of metastatic potential, rather than tumour grade.     

The association of chromosome 8p deletion and tumor metastasis in human hepatocellular carcinoma

To understand the genetic mechanisms underlying the progression of hepatocellular carcinoma (HCC) metastasis, differences of genomic alterations between 10 pairs of primary HCC tumors and their matched metastatic lesions were analyzed by comparative genomic hybridization. Several chromosomal alterations including loss of 8p, 4q, 17p, and 19p, gain of 5p and high-level amplification of 1q12-q22 were detected in two or more cases. The most significant finding is the loss of 8p which was detected in 8 metastatic tumors but only in 3 corresponding primary tumors (P = 0.03). This result suggests that the deletion of chromosome 8p might contribute to the development of HCC metastasis. Another interesting result is the detection of a minimum high-level amplification region at 1q12-q22 in HCC. This result provides a candidate amplification region in HCC for further study to identify amplified oncogenes related to the development or progression of HCC. Finally, this study provides a practicable model to detect specific genetic alterations related to the tumor metastasis through comparing the primary tumor and its corresponding metastatic lesion using comparative genomic hybridization technique.     

从门静脉癌栓建立肝癌细胞株及对其细胞遗传特征的研究

背景和目的：肝细胞癌（hepatocellular carcinoma,HCC)预后差的原因是术后复发率高和早期过门静脉转移。本研究建立门静脉癌栓肝癌细胞株,并探讨其分子细胞遗传特征。方法：从HCC患者门脉癌栓中获得取肝癌细胞进行细胞培养,对培养成功的细胞（H4M）进行染色体G带染色后分析其核型和对比基因组杂交（comparative genomic hybridization,CGH)结果;用差异PCR检测周期素D1基因。结果：H4M细胞核型为超3倍体,染色体数为71－78,其中有一条标记染色体含有一长的均染区（hsr)。H4M主要的细胞遗传学改变为8p缺失和11q13高拷贝数扩增。周期素D1基因CCND1明显扩增。结论：染色体8p丢失和11q13高拷贝数扩增与H4M细胞的转移特性相关。周期素D1基因CCND1扩增可能是染色体11q13扩增的原因。     

Malignant fibrous histiocytoma of bone: analysis of genomic imbalances by comparative genomic hybridisation and C-MYC expression by immunohistochemistry

Malignant fibrous histiocytoma (MFH) of bone is a rare, highly malignant tumour. As very little is known about its genetic alterations, 26 bone MFHs were analysed by comparative genomic hybridisation (CGH). Twenty-three tumours (89%) had DNA sequence copy number changes (mean, 7.2 changes per sample). Gains were more frequent than losses (gains:losses=2.5:1). Minimal common regions for the most frequent gains were 8q21.3-qter (35%), 9q32-qter (35%), 7q22-q31 (35%), 1q21-q23 (31%), 7p12-pter (31%), 7cen-q11.2 (31%) and 15q21 (31%). Minimal common regions for the most frequent losses were 13q21-q22 (42%) and 18q12-q22 (27%). High-level amplifications were detected in 8 out of the 26 tumours (31%). The only recurrent amplifications, 1q21-q23 and 8q21.2-q22, were present in two samples (8%). As copy number increase at 8q24 (the locus of C-MYC) was frequent, the expression of C-MYC was studied by immunohistochemistry. Increased levels of c-myc protein were detected in 7 out of 21 tumours studied (33%). 81% of the samples studied both by CGH and immunohistochemistry showed concordant results. Furthermore, the findings of the present study were compared to previous publications on osteosarcoma, soft tissue MFH and fibrosarcoma of bone. Clear differences were detected in CGH aberration patterns, further supporting the concept of bone MFH as an individual bone tumour entity. Finally, the findings of the present study reflect well the high malignancy and aggressive nature of bone MFH.     

Detection of genetic alterations in pancreatic cancers by comparative genomic hybridization coupled with tissue microdissection and degenerate oligonucleotide primed polymerase chain reaction

The aim of this study was to elucidate cytogenetic changes in pancreatic cancers (PCs) and to examine their clinical implications. We screened for genetic alterations in 32 primary PCs including 4 cases with distant organ metastasis using comparative genomic hybridization coupled with tissue microdissection and degenerate oligonucleotide primed polymerase chain reaction (DOP-PCR). The present study revealed frequent gains of chromosomes 13q and 15q and a loss of Xq in addition to a high prevalence of chromosomal imbalances. The average number of total genetic alterations and gains tended to be higher in N1 tumors (TNM classification) than in N0 tumors. The average number of amplifications was significantly higher in M1 tumors than in M0 tumors (p = 0.024). Gain/amplification of 20q was more frequently observed in M1 tumors than in M0 tumors (p = 0.016), and this change was also detected in all of 4 distant metastatic lesions. Losses of 6q, 8p, 9p, 17p, and 18q were recurrent in N0 and M0 tumors, and these alterations were also retained in N1 and M1 tumors. These observations suggest that these genetic losses contribute to the development of PCs and that increases in the DNA copy number confer an aggressive character on cancer cells. Especially, gain/amplification of 20q was associated with the potential of distant organ metastasis of tumor cells.     

DNA sequence copy number changes in gastrointestinal stromal tumors: tumor progression and prognostic significance

To identify genetic changes related to tumor progression and find out diagnostic and prognostic genetic markers in gastrointestinal stromal tumors (GISTs), 95 tumor samples (24 benign GISTs, 36 malignant primary GISTs, and 35 GIST-metastases) from 60 patients were studied using comparative genomic hybridization. DNA copy number changes were detected in all samples. Benign GISTs had a mean of 2.6 aberrations/ sample (losses:gains, 5:1) and significantly fewer DNA copy number changes and fewer gains than malignant primary and metastatic GISTs (P < 0.01). High-level amplifications were not seen in benign GISTs. Malignant primary GISTs had a mean of 7.5 aberrations/tumor (losses: gains, 1.6:1), whereas the mean number of aberrations/metastatic GIST was 9 (losses:gains, 1.8:1). Frequent changes observed in all GIST groups included losses in chromosome arms 1p (51%), 14q (74%), and 22q (53%). Gains and high-level amplifications at 8q and 17q were significantly more frequent in metastatic GISTs (57 and 43%) than in benign GISTs (8 and 0%; P < 0.001) and malignant primary GISTs (33 and 25%; P < 0.05). Gains and high-level amplifications at 20q were only seen in malignant primary and metastatic GISTs (P < 0.01), and gains at 5p were not detected in benign GISTs (P < 0.01). Losses in chromosome arm 9p were never seen in benign tumors (P < 0.001), and they were more frequent in metastatic GISTs than in malignant primary GISTs (63 and 36%; P < 0.05). Losses in 13q were less frequent in benign GISTs than in malignant primary (P < 0.05) and metastatic (P < 0.01) GISTs. Our results show that several DNA copy number changes are related to the behavior of GISTs and can be used as prognostic markers for tumor progression.     

Amplification on chromosomes 1p31, 1q21-24, 5p13-14, and 11p12-14 in ovarian-carcinoma detected by reverse chromosome painting

Recently, amplifications of several genes including c-myc, HER-2/neu, and FGF-3 (int-2) have been identified in ovarian carcinomas. We analyzed Il tumor samples from ovarian carcinoma for gene amplification using reverse chromosome painting and standard Southern blot analysis. Reverse chromosome painting detected four amplified domains on chromosome bands 1p31, 1q21-24, 5p13-14, and 11p12-14. None of the amplified domains contained genes previously reported to be amplified in ovarian carcinomas. Southern blot analysis revealed amplifications of genes HER2/neu, N-ras and H-ras. Tumor T3711 showed three independent amplifications including chromosome bands 1p31, 11p12-14 and the HER-2/neu gene (17q11.2-12).     

Survey of gene amplifications during prostate cancer progression by high-throughout fluorescence in situ hybridization on tissue microarrays

Prostate cancer development and progression is driven by the accumulation of genetic changes, the nature of which remains incompletely understood To facilitate high-throughput analysis of molecular events taking place in primary, recurrent, and metastat prostate cancer, we constructed a tissue microarray containing small 0.6-mm cylindrical samples acquired from 371 formalin-fixed blocks, including benign prostatic hyperplasia (n = 32) and primary tumors (n = 223), as well as both locally recurrent tumors (n = 54) and metastases (n = 62) from patients with hormone-refractory disease. Fluorescence in situ hybridization (FISH) was applied to the analysis of consecutive tissue microarray sections with probes for five different genes. High-level (> or =3X) amplifications were very rare (<2%) in primary prostate cancers However, in metastases from patients with hormone-refractory disease, amplification of the androgen receptor gene was seen in 22%, MYC in 11%, and Cyclin-D1 in 5% of the cases. In specimens from locally recurrent tumors, the corresponding percentages were 23, 4, and 8%. ERBB2 and NMYC amplifications were never detected at any stage of prostate cancer progression. In conclusion, FISH to tissue microarray sections enables high-throughput analysis of genetic alterations contributing to cancer development and progression. Our results implicate a role for amplification of androgen receptor in hormonal therapy failure and that of MYC in the metastatic progression of human prostate cancer.     

Alveolar rhabdomyosarcoma - primary and recurrent metastatic tumor has chromosomal translocation t(2-13)(q37-q14), amplified N-myc and is tumorigenic in nude-mice

Tissue specimens of primary and recurrent metastatic alveolar rhabdomyosarcoma (A-RMS) from a 12 year old child were cultured and shown to contain A-RMS specific t(2;13) (q37;q14) chromosomal translocation and to be tumourigenic in nude mice. Whereas c-myc protooncogene was neither amplified nor grossly rearranged, both biopsy samples were demonstrated to have 5-fold amplification of N-myc gene sequence. N-myc gene was also amplified in cell cultures produced by primary and metastatic tumour biopsies. Such a model for A-RMS has not been previously available.     

弥漫大B细胞淋巴瘤myc、bcl-2和bcl-6蛋白表达与基因异常的相关性研究

目的 探讨多重基因异常在弥漫大B细胞淋巴瘤(DLBCL)中的发生情况及其与蛋白高表达之间的关系.方法 收集2012年1月至2016年12月确诊的DLBCL非特指型患者50例,采用免疫组织化学法检测c-myc、bcl-2及bcl-6蛋白表达情况,采用间期荧光原位杂交(I-FISH)方法检测3个基因异常情况.结果 50例DLBCL患者中,男性27例,女性23例;年龄3~85岁,中位年龄50岁.发病部位:淋巴结23例(46.00%),结外27例(54.00%),以胃肠道最为多见(13例,48.15%).免疫组织化学检测c-myc蛋白阳性率94.00%(47/50),阳性细胞超过40%者41例(82.00%);bcl-2蛋白阳性率84.00%(42/50),阳性细胞超过70%者38例(76.00%);18例(36.00%)同时高表达c-myc和bcl-2.FISH检测结果显示,7例(14.00%)c-myc断裂,2例(4.00%)扩增;6例(12.00%)bcl-2断裂,4例(8.00%)扩增;8例(16.00%)bcl-6断裂,3例(6.00%)扩增,1例(2.00%)同时断裂及扩增;4例(8.00%)检测到多重基因异常,其中1例(2.00%)c-myc合并bcl-2基因异常,2例(4.00%)c-myc合并bcl-6基因异常,为双重打击淋巴瘤(DHL),1例(2.00%)同时检测到c-myc、bcl-2及bcl-6基因异常,为三重打击淋巴瘤(THL).4例多重基因异常病例中,3例起源于生发中心B细胞(GCB),1例起源于非GCB.18例c-myc和bcl-2蛋白双高表达组仅有3例(16.67%)检测到多重基因异常,包括2例DHL和1例THL.结论 多重基因异常在DLBCL中的检出率为8.00%.基因异常与蛋白高表达之间无明显相关性,DHL的检出依赖于分子遗传学检测.     

Relationship between human papillomavirus and oncogenes (c-myc, N-myc) amplification in human cervical cancers

The human papillomavirus detection and oncogenes amplifications were studied on DNAs from fifteen cervical cancers. We detected HPV16 and HPV18 using Southern blot hybridization and polymerase chain reaction (PCR) technique. The positive subjects of HPVs were eight cases (53%) observed by Southern blot hybridization and fourteen cases (93%) by PCR technique. The gene amplifications of oncogenes (c-myc and N-myc) were analysed by slot-blot method and were observed in c-myc but not in N-myc. The "LARGE" gene amplification (more than five fold) in c-myc was observed in one case (7%) and the "SMALL" gene amplifications (less than five fold) were observed in six cases (40%) in human cervical cancers. Although one of five cases (20%) with HPV16 was present c-myc gene amplification, all of three cases (100%) with HPV18 were found c-myc gene amplifications. In two out of three cases obtained more than three fold c-myc gene amplifications, HPV were not detectable. It is suggested that the negative correlation between gene amplification and numbers of HPV copies exist in advanced cervical cancers.     

Molecular cytogenetic analysis of 11 new breast cancer cell lines

We describe a survey of genetic changes by comparative genomic hybridization (CGH) in 11 human breast cancer cell lines recently established in our laboratory. The most common gains took place at 8q (73%), 1 q (64%), 7q (64%), 3q (45%) and 7p (45%), whereas losses were most frequent at Xp (54%), 8p (45%), 18q (45%) and Xq (45%). Many of the cell lines displayed prominent, localized DNA amplifications by CGH. One-third of these loci affected breast cancer oncogenes, whose amplifications were validated with specific probes: 17q12 (two cell lines with ERBB2 amplifications), 11q13 (two with cyclin-D1), 8p11-p12 (two with FGFR1) and 10q25 (one with FGFR2). Gains and amplifications affecting 8q were the most common genetic alterations in these cell lines with the minimal, common region of involvement at 8q22-q23. No high-level MYC (at 8q24) amplifications were found in any of the cell lines. Two-thirds of the amplification sites took place at loci not associated with established oncogenes, such as 1q41-q43, 7q21-q22, 7q31, 8q23, 9p21-p23, 11p12-p14, 15q12-q14, 16q13-q21, 17q23, 20p11-p12 and 20q13. Several of these locations have not been previously reported and may harbour important genes whose amplification is selected for during cancer development. In summary, this set of breast cancer cell lines displaying prominent DNA amplifications should facilitate discovery and functional analysis of genes and signal transduction pathways contributing to breast cancer development.     

Amplifications of TAOS1 and EMS1 genes in oral carcinogenesis: association with clinicopathological features

Amplification of chromosomal region 11q13 is one of the genetic alterations most frequently observed in oral squamous cell carcinoma (OSCC). Both TAOS1, a recently identified gene, and EMS1 were thought as two important target oncogenes for driving 11q13 amplification, and their contributions to oral carcinogenesis were hypothesized. Therefore we investigated amplifications of TAOS1 and EMS1 genes and their relations to clinicopathological variables in premalignant lesions (leukoplakias) and primary OSCC. TAOS1 amplification, beginning from mild-dysplastic epithelia, occurred in 33.3% of leukoplakias and 51.5% of OSCC. EMS1 amplification, beginning from moderate-dysplastic epithelia, occurred in 20% of leukoplakias and 57.6% of OSCC. Both gene amplifications were significantly related to different stages of oral carcinogenesis (p<0.05). During multistage carcinogenesis, no gene amplification was observed in normal tissue and non-dysplastic leukoplakias while, in OSCC with metastasis, amplification frequency increased significantly (p<0.005). Both TAOS1 and EMS1 amplifications were significantly associated with larger tumor size, presence of lymph node metastasis, poor histological differentiation and advanced clinical stage. Our data suggested potential roles in oral carcinogenesis and that TAOS1 might be involved earlier than EMS1. Both genes might be candidate biomarkers for diagnosis and prognosis in OSCC.     

Clinicopathologic significance and prognostic value of chromosomal imbalances in diffuse large B-cell lymphomas.

PURPOSE: To determine the clinicopathologic significance and prognostic value of chromosomal imbalances in diffuse large B-cell lymphomas (DLBCL). PATIENTS AND METHODS: We have examined 64 tumors at diagnosis using comparative genomic hybridization and real-time quantitative polymerase chain reaction (PCR), single-stranded conformational polymorphism, and DNA sequencing for the analysis of several potential target genes. RESULTS: The most recurrent alterations were gains of 18q (20%), Xq (15%), 2p, 7q, and 12p (14%), and losses of 6q and 17p (14%). Frequent high-level DNA amplifications were detected at 2p13-p16 and 18q21 loci. Real-time quantitative PCR detected REL and BCL11A gene amplifications in the nine patients with gains at 2p13-p16 and only in one additional patient with normal chromosome 2. Similarly, the BCL-2 gene was amplified in the 12 tumors with gains of 18q21 but in none of 39 patients with normal 18q profile. p53 gene inactivation was detected in nine of 58 (16%) tumors and was commonly associated with 17p losses. Tumors with 18q gains were significantly associated with a high number of chromosomal imbalances, primary nodal presentation, high serum lactate dehydrogenase levels, high International Prognostic Index, shorter cause-specific survival, and a high risk of relapse. Losses of 17p and p53 gene alterations were associated with an absence of complete response achievement. CONCLUSION: These results suggest that DLBCLs have a characteristic pattern of genomic alterations; 18q gains or amplifications and 17p losses are associated with particular clinicopathological features and aggressive clinical behavior. Additional studies are needed to confirm these observations in larger series of patients.     

Cellular protoonocogenes are infrequently amplified in untreated non-small cell lung cancer

To examine a potential contribution of protooncogene abnormalities other than point-mutational activation of the K-ras protooncogene in the classification of non-small cell lung cancer, amplification of cellular protooncogenes was studied in 47 lung tumour specimens obtained at thoracotomy and in four lung tumour cell lines. The primary tumours included 21 adenocarcinomas, nine large-cell carcinomas, 13 epidermoid carcinomas, one carcinoid and three metastases of primaries outside the lung. The copy numbers per haploid genome of 11 protooncogenes in every tumour sample were determined: H-ras, K-ras, N-ras, c-myc, N-myc, L-myc, erbB, mos, myb, ncu (erbB-2) and ral amplifications. The c-myc gene was amplified 5-7-fold in two adenocarcinomas, the H-ras gene 3 5-fold in one adenocarcinoma, while the K-ras and the neu gene were amplified in lung metastases from a colorectal and a breast cancer primary respectively. None of the tumours with an amplified protooncogene simultaneously harboured a mutationally activated K-ras gene. We conclude that amplification of the investigated protooncogenes is a rare event in non-small cell lung cancer. In view of the two c-myc amplifications detected, a systematic study of c-myc expression levels in non-small cell lung cancers appears worthwhile.     

Correlations between c-myc gene copy-number and clinicopathological parameters of ovarian tumours

The objective of this study was to investigate increases in c-myc gene copy-number in ovarian tumours, and to analyze their correlations with clinicopathological parameters. Here we applied FISH on TMA (tissue microarrays) containing 507 ovarian tumour samples from different malignancy, histology, stage and grade. Overall, we found high frequency for c-myc copy-number increases (38.5%) in ovarian cancers: 22.1% amplifications and 16.4% gains. We established c-myc amplification in more than 30% in endometrioid and mixed epithelial ovarian carcinomas. c-myc gains were found in a high proportion (42.9%) of clear cell carcinomas. We found associations between c-myc copy-number changes and clinicopathological parameters of ovarian tumours such as degree of malignancy and histological type. We suggested that c-myc amplifications are characteristics for endometrioid, and c-myc gains for clear cell ovarian cancers. We suggest that copy-number increases of c-myc and 20q13.2 represent a possible mechanism for the regulation of the pathway STK15--c-myc--hTERT.     

High-resolution analysis of chromosomal breakpoints and genomic instability identifies PTPRD as a candidate tumor suppressor gene in neuroblastoma

Although neuroblastoma is characterized by numerous recurrent, large-scale chromosomal imbalances, the genes targeted by such imbalances have remained elusive. We have applied whole-genome oligonucleotide array comparative genomic hybridization (median probe spacing 6 kb) to 56 neuroblastoma tumors and cell lines to identify genes involved with disease pathogenesis. This set of tumors was selected for having either 11q loss or MYCN amplification, abnormalities that define the two most common genetic subtypes of metastatic neuroblastoma. Our analyses have permitted us to map large-scale chromosomal imbalances and high-level amplifications at exon-level resolution and to identify novel microdeletions and duplications. Chromosomal breakpoints (n = 467) generating imbalances >2 Mb were mapped to intervals ranging between 6 and 50 kb in size, providing substantial information on each abnormality. For example, breakpoints leading to large-scale hemizygous loss of chromosome 11q were highly clustered and preferentially associated with segmental duplications. High-level amplifications of MYCN were extremely complex, often resulting in a series of discontinuous regions of amplification. Imbalances (n = 540) <2 Mb long were also detected. Although the majority (78%) of these imbalances mapped to segmentally duplicated regions and primarily reflect constitutional copy number polymorphisms, many subtle imbalances were detected that are likely somatically acquired alterations and include genes involved with tumorigenesis, apoptosis, or neural cell differentiation. The most frequent microdeletion involved the PTPRD locus, indicating a possible tumor suppressor function for this gene.     

Distinct chromosomal imbalances in pleomorphic and in high-grade dedifferentiated liposarcomas

Using comparative genomic hybridization, DNA copy number changes were studied in 14 pleomorphic liposarcomas and compared to those detected in high-grade areas of 9 dedifferentiated liposarcomas. A total of 251 gains and 84 losses were detected. The most frequent gains involved subregions of chromosomal arms 12q and 20q (70% each), 5p (57%), 6q and 9q (52% each), 1q, 7p and 17p (48% each), 1p (43%), 6p and 17q (39% each), 20p and 22q (35% each) as well as 7q and 12p (30% each). The same subregions were also affected by 30 high level amplifications. The most frequent losses were found in subregions of chromosomal arms 13q (35%) as well as 11q and 12p (30% each). Overall, gains of chromosomal material were more frequent than losses (p < 0.001). There were significant differences in the frequency and distribution of recurrent chromosomal imbalances between pleomorphic liposarcomas and the dedifferentiated areas of dedifferentiated liposarcomas. Gains of chromosomal material detected predominantly in pleomorphic liposarcomas involved subbands 5p13-p15 (p < 0.010), 1p21 (p < 0.019), 1q21-q22 (p < 0.040) and 7q22 (p < 0.049). Conversely, high level amplifications within chromosomal subregion 12q13-q21 were only found in the dedifferentiated components of dedifferentiated liposarcomas (p < 0.001). Overall, both gains and the less pronounced losses of chromosomal material were more frequent in pleomorphic than in dedifferentiated liposarcomas (p < 0.001 and p < 0.025, respectively). These results show that pleomorphic liposarcomas display a considerable number of recurrent chromosomal imbalances that are essentially different from those present in high-grade areas of dedifferentiated liposarcomas. Therefore, genetic data are considered as a helpful diagnostic adjunct for the discrimination between these 2 types of liposarcoma. The overall higher frequency of chromosomal imbalances in pleomorphic as compared to dedifferentiated liposarcomas could account for the more aggressive biological behavior of pleomorphic relative to dedifferentiated liposarcoma types.