Frequent gains on chromosome arms 1q and/or 8q in human endometrial cancer

Low-Pass Genomic Sequencing Reveals Novel Subtypes of Pancreatic Cystic Neoplasms

BACKGROUND

Over the years, the detection rate of pancreatic cystic neoplasms (PCNs) has significantly increased; however, the differential diagnosis and identification of high-risk PCNs remain challenging. We sought to investigate whether chromosomal instability (CIN) features in cell-free DNA in the cystic fluid of PCNs could help to identify high-risk PCNs.

METHODS

Pancreatic cystic fluid samples from 102 patients with PCNs were intraoperatively collected for detection of CIN using an ultrasensitive chromosomal aneuploidy detector. Clinical and imaging data were retrospectively collected, and statistical analysis was performed to assess the potential role of CIN in clinical practice.

RESULTS

CIN was investigated in a total of 100 patients. Sixteen of 26 serous cystic cystadenomas (SCAs) harbored deletions of chr3p and/or chr6p, whereas low rates of CIN were detected in mucinous cystic neoplasms. Most malignant PCNs presented with more than one type of CIN; amplification of chr1q and chr8q found in nine and seven of 11 malignant PCNs (81.8% and 63.6%), respectively, could aid in distinguishing high-risk IPMNs from low-risk ones, with a higher sensitivity than imaging. A combination of the mural nodule imaging feature and amplification of chr1q and chr8q achieved a sensitivity of 70.0% and a specificity of 82.4% in identifying high-risk IPMNs.

CONCLUSIONS

Our work revealed the distinct CIN signature of different types of PCNs. Deletions of chr3p and chr6p defined a subtype of SCAs. Gains of chr1q and chr8q were associated with insidious malignant PCNs and helped identify high-risk IPMNs.

Fluorescence in situ hybridization test for detection of endometrial carcinoma cells by non-invasive vaginal swab

Endometrial cancer (EC) is the most common gynaecological malignancy with increasing incidence in developed countries. As gold standard, hysteroscopy confirms only 30% of suspected ECs. The detection of EC cells in the vagina by fluorescence in situ hybridization (FISH) after a smear test could reduce invasive procedures in the future. Using array-based comparative genome hybridization (aCGH) on 65 endometrial carcinomas, most frequently imbalanced regions of the tumour genome were identified. Bacterial artificial chromosomes were used to generate FISH-probes homologue to these human regions. The FISH test was hybridized on swabs specimens collected from the vaginal cavity. Samples from six patients without EC were selected as a negative control and on 13 patients with known EC as a positive control. To distinguish between benign and EC cases, the cut-off value has been defined. A first validation of this EC-FISH Test was performed with swabs from 41 patients with suspected EC. The most common genomic imbalances in EC are around the CTNNB1, FBXW7 and APC genes. The cut-off is defined at 32% of analysed cells without diploid signal pattern. This differs significantly between the positive and negative controls (p < 0.001). In a first validation cohort of 41 patients with suspected EC, the EC-FISH Test distinguishes patients with and without EC with a sensitivity of 91% and a specificity of 83%. The negative predictive value is 96%. This is the first report of a non-invasive EC-FISH Test to predict EC in women with suspected EC.

High-resolution copy number analysis of clear cell endometrial carcinoma

Uterine cancer is the 6th leading cause of cancer death amongst American women. Most uterine cancers are endometrial carcinomas (ECs), which are classified into histological subtypes including endometrioid, serous, and clear cell ECs. Somatic copy number alterations (SCNAs) are frequent in serous EC, infrequent in endometrioid ECs, and poorly defined in clear cell ECs. The purpose of this study was to evaluate the occurrence of SCNAs in clinically diagnosed clear cell ECs. Paired tumor-normal DNAs for 51 ECs were hybridized to Illumina Infinium HumanHap650Y or Human660W-Quad Beadchips. Copy number calls were made using the Hidden Markov Model based SNP-FASST2 segmentation algorithm within Nexus Copy Number software (v.6.1). High-level SCNAs were defined as gain of ≥5 copies or homozygous deletion, both <10Mb. GISTIC 1.0, in Nexus, was used to identify statistically significant SCNAs, corrected for multiple testing. One or more high-level SCNAs were detected in 50% of 6 clear cell ECs, 78.6% of 28 serous ECs, and 17.6% of 17 endometrioid ECs. A positive association was found between high-level SCNAs and TP53 mutation across ECs (two-tailed p value<0.0001). Classifying tumors according to POLE, MSI, and TP53 status yielded four molecular subgroups; copy number altered tumors were more frequent in the TP53-mutated subgroup (95.8%) than in the unspecified subgroup (22.2%), and absent from the POLE and MSI subgroups. In conclusion, our study provides evidence of inter-tumor heterogeneity in the extent to which SCNAs occur in clinically diagnosed clear cell EC, and across molecular subgroups of EC. The co-occurrence of high-level SCNAs and TP53 mutations in some clear cell ECs is consistent with the view that a subset of clinically diagnosed clear cell ECs have molecular similarities to serous ECs.

Aurora kinase A interacts with H-Ras and potentiates Ras-MAPK signaling

In cancer, upregulated Ras promotes cellular transformation and proliferation in part through activation of oncogenic Ras-MAPK signaling. While directly inhibiting Ras has proven challenging, new insights into Ras regulation through protein-protein interactions may offer unique opportunities for therapeutic intervention. Here we report the identification and validation of Aurora kinase A (Aurora A) as a novel Ras binding protein. We demonstrate that the kinase domain of Aurora A mediates the interaction with the N-terminal domain of H-Ras. Further more, the interaction of Aurora A and H-Ras exists in a protein complex with Raf-1. We show that binding of H-Ras to Raf-1 and subsequent MAPK signaling is enhanced by Aurora A, and requires active H-Ras. Thus, the functional linkage between Aurora A and the H-Ras/Raf-1 protein complex may provide a mechanism for Aurora A's oncogenic activity through direct activation of the Ras/MAPK pathway.

Amplification of 1q32.1 Refines the Molecular Classification of Endometrial Carcinoma

Purpose: Molecular classification of endometrial cancer identified distinct molecular subgroups. However, the largest subset of endometrial cancers remains poorly characterized and is referred to as the "nonspecific molecular profile" (NSMP) subgroup. Here, we aimed at refining the classification of this subgroup by profiling somatic copy-number aberrations (SCNAs).Experimental Design: SCNAs were analyzed in 141 endometrial cancers using whole-genome SNP arrays and pooled with 361 endometrial cancers from The Cancer Genome Atlas. Genomic Identification of Significant Targets in Cancer (GISTIC) identified statistically enriched SCNAs and penalized Cox regression assessed survival effects. The prognostic significance of relevant SCNAs was validated using multiplex ligation-dependent probe amplification in 840 endometrial cancers from the PORTEC-1/2 trials. Copy-number status of genes was correlated with gene expression to identify potential cancer drivers. One plausible oncogene was validated in vitro using antisense oligonucleotide-based strategy.Results: SCNAs affecting chromosome 1q32.1 significantly correlated with worse relapse-free survival (RFS) in the NSMP subgroup (HR, 2.12; 95% CI, 1.26-3.59; P = 0.005). This effect was replicated in NSMP endometrial cancers from PORTEC-1/2 (HR, 2.34; 95% CI, 1.17-4.70; P = 0.017). A new molecular classification including the 1q32.1 amplification improved risk prediction of recurrence. MDM4 gene expression strongly correlated with 1q32.1 amplification. Silencing MDM4 inhibited cell growth in cell lines carrying 1q32.1 amplification, but not in those without MDM4 amplification. Vice versa, increasing MDM4 expression in nonamplified cell lines stimulated cell proliferation.Conclusions: 1q32.1 amplification was identified as a prognostic marker for poorly characterized NSMP endometrial cancers, refining the molecular classification of this subgroup. We functionally validated MDM4 as a potential oncogenic driver in the 1q32.1 region. Clin Cancer Res; 23(23); 7232-41. ©2017 AACR.

Molecular analysis of isolated tumor glands from endometrial endometrioid adenocarcinomas

We studied the extensive molecular alterations of endometrial endometrioid adenocarcinoma (EEA) using a crypt isolation method. We analyzed copy number variation (CNV) using a single nucleotide polymorphism (SNP) array, genetic mutations (KRAS, BRAF, p53, PIK3CA), DNA methylation and microsatellite instability (MSI) status. In addition, loss of PTEN protein expression was examined. Increased chromosome copy numbers of 1q21.2-44 (22%) and 10q11.21-23.31 (28%) were seen relatively frequently in EEA, and copy-neutral loss of heterozygosity (LOH) was also observed in 10q22.1-26.3 (22%). The CNV patterns of EEA were classified into four groups through hierarchical cluster analysis. Cluster 1 had many CNVs of 10q, and cluster 2 was characterized by MSI status. In cluster 3, increased CNVs of 1q were often seen. In cluster 4, p53 mutations were detected. KRAS and PIK3CA mutations and reduced PTEN protein expression were common to all groups. On the other hand, CpG island methylator phenotype (CIMP) was rare in all groups. The data indicated an association with chromosomal gain of 1q and 10q or 10q copy-neutral LOH in some cases. We suggest that EEA consists of four groups that are characterized with molecular alterations.

Genomic characterization of endometrial stromal sarcomas with array comparative genomic hybridization

INTRODUCTION

The endometrial stromal sarcoma (ESS) is a very rare uterine sarcoma, counting for 1-3% of all gynecologic malignancies. ESS represents 0.2-8% of all uterine malignant tumors and accounts for about 10% of all uterine sarcomas. With regard to chromosomal aberrations, very little is known about benign and malignant endometrial stromal tumors.

METHODS

30 tumors, consisting of 4 cases of benign endometrial stromal nodule (ESN), 22 cases of low-grade ESS and 4 cases of undifferentiated endometrial sarcoma (UES), were analyzed by array-comparative genomic hybridization (aCGH).

RESULTS

ESN did not show many copy number changes (CNCs) by aCGH. Frequent losses could be identified on chromosomes 7p and 19, and gains on chromosomes 1q, 6p and 8q. Low-grade ESS presented as a very heterogeneous group. 90% (20/22) of cases displayed aberrations. Most frequent changes were losses on chromosomes 7 and 22, and gains on chromosome 1q or 11. UES showed a high number of chromosomal aberrations and on every chromosome CNCs were detected. Most frequent changes were losses on chromosomes 1q, 2q (3/4, 75%) and 13, and gains on chromosomes 1q and 17p.

CONCLUSION

Our data shows an increasing number of CNCs from ESN to low-grade ESS and to UES. However, the chromosomal aberrations differ considerably between the investigated ESN-, low-grade ESS- and UES cases and thus, a linear tumor progression seems to be unlikely.

The effect of first chromosome long arm duplication on survival of endometrial carcinoma

Objective:

The aim of this study is to investigate the effect of first chromosome long arm duplication (dup(1q)) in cases with endometrial carcinoma detected with array based comperative genomic hybridization (aCGH) on survival from the cancer.

Materials and Methods:

A total of 53 patients with the diagnosis of endometrial carcinom due to endometrial biopsy and who have been operated for this reason have been allocated in the study. Frozen section biopsy and staging surgery have been performed for all the cases. Samples obtained from the tumoral mass have been investigated for chromosomal aberrations with aCGH method. Kaplan-Meier and Cox-regression analysis have been performed for survival analysis.

Results:

Among 53 cases with endometrial carcinomas, dup(1q) was diagnosed in 14 (26.4%) of the cases. For the patient group that has been followed-up for 24 months (3-33 months), dup(1q) (p=.01), optimal cytoreduction (p<.001), lymph node positivity (p=.006), tumor stage >1 (p=.006) and presence of high risk tumor were the factors that were associated with survival. Cox-regression analysis has revealed that optimal cytoreduction was the most important prognostic factor (p=.02).

Conclusion:

Presence of 1q duplication can be used as a prognostic factor in the preoperative period.

Impact of genomic stability on protein expression in endometrioid endometrial cancer

Background:

Genomic stability is one of the crucial prognostic factors for patients with endometrioid endometrial cancer (EEC). The impact of genomic stability on the tumour tissue proteome of EEC is not yet well established.

Methods:

Tissue lysates of EEC, squamous cervical cancer (SCC), normal endometrium and squamous cervical epithelium were subjected to two-dimensional (2D) gel electrophoresis and identification of proteins by MALDI TOF MS. Expression of selected proteins was analysed in independent samples by immunohistochemistry.

Results:

Diploid and aneuploid genomically unstable EEC displayed similar patterns of protein expression. This was in contrast to diploid stable EEC, which displayed a protein expression profile similar to normal endometrium. Approximately 10% of the differentially expressed proteins in EEC were specific for this type of cancer with differential expression of other proteins observed in other types of malignancy (e.g., SCC). Selected proteins differentially expressed in 2D gels of EEC were further analysed in an EEC precursor lesion, that is, atypical hyperplasia of endometrium, and showed increased expression of CLIC1, EIF4A1 and PRDX6 and decreased expression of ENO1, ANXA4, EMD and Ku70.

Conclusion:

Protein expression in diploid and aneuploid genomically unstable EEC is different from the expression profile of proteins in diploid genomically stable EEC. We showed that changes in expression of proteins typical for EEC could already be detected in precursor lesions, that is, atypical hyperplasia of endometrium, highlighting their clinical potential for improving early diagnostics of EEC.

Genomic imbalances in endometrial adenocarcinomas - comparison of DNA ploidy, karyotyping and comparative genomic hybridization

DNA ploidy analysis is useful for prognostication in cancer patients, but the genomic details underlying ploidy changes are not fully understood. To improve this understanding, we compared DNA ploidy status with karyotypic and comparative genomic hybridization data on 51 endometrial adenocarcinomas. Out of 34 DNA diploid tumors evaluated by CGH, 16 (47%) showed imbalances, though only two had more than four copy number changes. Ten (29%) had aberrations involving chromosome 1, seven (21%) involving chromosome 10, while one tumor had a chromosome 8 aberration. Four of the seven DNA tetraploid tumors (57%) had imbalances detected by CGH with two (29%) having more than four. Six out of eight DNA aneuploid tumors showed imbalances by CGH, with five (63%) having more than four. The aberrations were observed on chromosomes 1 and 8 in five/eight (63%) cases while four imbalances (50%) involved chromosomes 5, 7 and X. Not surprisingly, we observed a significant correlation between increasing DNA ploidy complexity and increasing number of copy alterations. Gains of material from chromosomes 8 and 7 might be specifically correlated to DNA aneuploidy in endometrial adenocarcinomas since 63% and 50% of the aneuploid compared to 3% of the diploid tumors showed imbalances involving these chromosomes.

Genomic profile of endometrial tumors depends on morphological subtype, not on tamoxifen exposure

Tamoxifen has been a very effective treatment for breast cancer for several decades, however, at the same time increases the risk of endometrial cancer, especially after prolonged exposure. In addition, tamoxifen has been associated with a higher proportion of unfavorable uterine tumor subtypes (carcinosarcomas and serous adenocarcinomas) with worse survival. We investigated whether endometrial tumors, which developed after prolonged tamoxifen treatment for breast cancer, are genetically different from endometrial tumors without preceding tamoxifen exposure. Array CGH was used on archival formalin-fixed paraffin embedded endometrial tumors to determine genomic aberrations. We compared the genomic profiles of 52 endometrial tumors from breast cancer patients after long-term (>or=2 years) tamoxifen use (endometrioid adenocarcinomas, n = 26; carcinosarcomas, n = 14; and serous adenocarcinomas, n = 12) with endometrial tumors from unexposed breast cancer patients (n = 45). Genomic profiles were correlated with tamoxifen exposure, tumor subtypes, and histopathological characteristics of the endometrial tumors. The common uterine corpus cancers of the endometrioid subtype show few genomic aberrations. Tumors with many genomic aberrations were in general ER-negative. In contrast, carcinosarcomas and serous adenocarcinomas showed many aberrations; however, they were indistinguishable from each other. Tumors that developed after prolonged tamoxifen use did not show more or different aberrations than unexposed tumors. This was true for all tumor subtypes. Thus, endometrial carcinomas that develop after prolonged tamoxifen use cannot be distinguished from nonusers on basis of their tumor genomic profile.

Detection of chromosomal anomalies in endometrial atypical hyperplasia and carcinoma by using fluorescence in situ hybridization

BACKGROUND

Endometrial cancer is the most common pelvic gynecological malignancy. The diagnosis of well-differentiated endometrial adenocarcinoma, atypical hyperplasia, and hyperplasia is often challenging. The authors sought to investigate the utility of chromosomal anomalies for the detection of endometrial hyperplasia and carcinoma using multitarget fluorescence in situ hybridization (FISH).

METHODS

Samples were collected by endometrial Tao brush and processed by liquid-based cytological preparation protocol from consecutive cases to include 50 benign, 50 hyperplasia without atypia, 47 atypical hyperplasia, and 53 endometrial cancers. Each was hybridized using fluorescence-labeled DNA probes to chromosomes 1, 8, and 10. The FISH signals were enumerated in 100 cells per case, and the chromosomal anomalies were correlated with pathologic findings, including histologic diagnoses on matched endometrial tissue samples.

RESULTS

Numeric chromosomal anomalies were found in 0% (0 of 50) of benign, 20% (10 of 50) of hyperplasia, 74% (35 of 47) of atypical hyperplasia, and 87% (46 of 53) of carcinoma specimens. The mean percentage of cells with chromosomal changes was 55% in cancer specimens, which was significantly higher than that in hyperplasia without atypia (13%, P < .0001) and atypical hyperplasia (32%, P = .003). The most frequent chromosomal anomaly was gain of chromosome 1. FISH anomalies had an overall sensitivity of 81% and specificity of 90% for the detection of atypical hyperplasia and/or endometrial carcinoma. There was no association with grade of endometrial carcinoma.

CONCLUSIONS

Multitarget FISH appears to be useful for the differential diagnosis of hyperplasia, atypical hyperplasia, and endometrial adenocarcinoma, with a high level of sensitivity and specificity. It is also a potential tool for the early detection of neoplastic cells in endometrial cytology specimens. Endometrial hyperplasia with FISH-detected chromosomal anomalies may represent a clinically significant subset of cases that warrant close clinical follow-up.

Analysis of chromosome 10 aberrations in rat endometrial cancer-evidence for a tumor suppressor locus distal to Tp53

We have recently shown in the BDII rat model of human endometrial adenocarcinoma (EAC), rat chromosome 10 (RNO10) is frequently involved in chromosomal aberrations. In the present study, we investigated the association between RNO10 deletions, allelic imbalance (AI) at RNO10q24 and Tp53 mutation in 27 rat EAC tumors. We detected chromosomal breakage accompanied by loss of proximal and/or gain of distal parts of RNO10 in approximately 2/3 of the tumors. This finding is suggestive of a tumor suppressor activity encoded from the proximal RNO10. Given the fact that Tp53 is located at RNO10q24-q25, we then performed Tp53 mutation analysis. However, we could not find a strong correlation between AI/deletions at RNO10q24 and Tp53 mutation. Instead, the observed patterns for AI, chromosomal breaks and deletions suggest that major selection was directed against a region located close to, but distal of Tp53. In different human malignancies a similar situation of AI at chromosome band 17p13.3 (HSA17p13.3) unassociated with TP53 mutation has been observed. Although RNO10 is largely homologous to HSA17, the conservation with respect to gene order among them is not extensive. We utilized publicly available draft DNA sequences to study intrachromosomal rearrangement during the divergence between HSA17 and RNO10. By using reciprocal comparison of rat and human genome data, we could substantially narrow down the candidate tumor suppressor region in rat from 3 Mb to a chromosomal segment of about 0.5 Mb in size. These results provide scientific groundwork for identification of the putative tumor suppressor gene(s) at 17p13.3 in human tumors.

Chromosomal alterations in 98 endometrioid adenocarcinomas analyzed with comparative genomic hybridization

The aim of the present study was to investigate chromosomal alterations in a large set of homogeneous tumors, 98 endometrioid adenocarcinomas. We also wanted to evaluate differences in chromosomal alterations in the different groups of tumors in relation to stage, survival and invasive or metastatic properties of the tumors. Comparative genomic hybridization (CGH) was used to detect chromosomal alterations in tissue samples from 98 endometrioid adenocarcinomas. All chromosomes were involved in DNA copy number variations at least once in the tumor material, but certain changes were recurrent and rather specific. Among the specific changes, it was possible to identify 39 chromosomal regions displaying frequent DNA copy number alterations. The most frequent alteration was detected at 1q25-->q42, in which gains were found in 30 cases (30%). Gains at 19pter-->p13.1 were detected in 26 tumors (26%) and at 19q13.1-->q13.3 in 19 tumors (19%). Increased copy numbers were also detected at 8q (8q21-->q22 and 8q22-->qter), at a relatively high rate, in 17 cases (17%). Furthermore, gains at 10q21-->q23 and 10p were found in 14 (14%) and 13 cases (13%), respectively. The most common losses were found in the three regions 4q22-->qter, 16q21-->qter and 18q21-->qter, all of which were detected in eight of the 98 tumors (8%). We also detected differences between the tumors from deceased patients and from survivors. Gain at 1q25-->q42 was more commonly detected in the tumors from patients who died of cancer. We noted that the regions most affected differed in the different surgical stages (I-IV). The results of the CGH analysis identify specific chromosomal regions affected by copy number changes, appropriate objects for further genetic studies.

Gene Expression Profiling of Microsatellite Unstable and Microsatellite Stable Endometrial Cancers Indicates Distinct Pathways of Aberrant Signaling

Microsatellite instability (MSI) is a molecular phenotype present in approximately 25% of endometrial cancers. We examined the global gene expression profiles of early-stage endometrioid endometrial cancers with and without the MSI phenotype to test the hypothesis that MSI phenotype may determine a unique molecular signature among otherwise similar cancers. Unsupervised principal component analysis of the expression data from these cases indicated two distinct groupings of cancers based on MSI phenotype. A relatively small number of array features (392) at high statistical value (P < 0.001) were identified that drive the instability signature in these cancers; 109 of these transcripts differed by at least 2-fold. These data identify distinct gene expression profiles for MSI and microsatellite stable (MSS) cancers, which suggest that cancers with MSI develop in part by different mechanisms from their similar stable counterparts. In particular, we found evidence that two members of the secreted frizzled related protein family (SFRP1 and SFRP4) were more frequently down-regulated in MSI cancers as compared with MSS cancers. Down-regulation was accompanied by promoter hypermethylation for SFRP1. SFRP1 was hypermethylated in 8 of 12 MSI cancers whereas only 3 of 16 MSS cancers were methylated. The WNT target fibroblast growth factor 18 was found to be up-regulated in MSI cancers. These data classify histologically similar endometrioid endometrial cancers into two distinct groupings with implications affecting therapy and prevention.

Genetic imbalances in endometrial hyperplasia and endometrioid carcinoma detected by comparative genomic hybridization

OBJECTIVE

To evaluate the sequential genomic copy alterations related to the development of precursor lesions and endometrioid-type endometrial carcinomas, and its association with cellular atypia.

STUDY DESIGN

Paraffin-embedded tissue specimens from 32 cases of endometrial hyperplasia, 15 of endometrial carcinoma, and 20 of normal endometrial tissue were retrospectively evaluated by the comparative genomic hybridization (CGH) technique. The average number of copy alterations (ANCA) index was used to define the incidence of genomic imbalances in each tissue group. Identified sequential genetic abnormalities were compared with the final histopathological diagnosis and the cellular atypia.

RESULTS

Detectable and consistent chromosomal imbalances were found in 13 hyperplasia and 9 carcinoma specimens. There was a significant correlation between ANCA value and degree of cellular atypia and tumor grade. While 1p36-pter, 20q deletions, and 4q overrepresentation were the most prevalent imbalances detected in both complex hyperplasia and complex atypical hyperplasia, 17q22-qter deletion and amplification of 2p34 were only seen in hyperplasia with atypical cells. Overrepresentations of chromosomes 8q, 1q, and 3q are the most frequent aberrations in endometrial carcinomas, but were absent from all the precursor lesions except one. Underrepresentations of chromosomes 1p36-pter and 10q are the other commonly seen aberrations in carcinomas, the latter being more frequent in moderately differentiated than in poorly differentiated lesions.

CONCLUSIONS

Different patterns of chromosomal aberrations are seen in precursor lesions than in endometrial carcinomas, except for the loss of 1p36-pter. The presence of 1p deletion in both endometrial hyperplasia and cancer specimens suggests that this is an early event in the development of carcinoma. These results support a stepwise mode of tumorigenesis with accumulation of a series of genomic copy alterations in endometrial carcinogenesis.

Loss of heterozygosity alterations associated with progesterone therapy in endometrial hyperplasia and adenocarcinoma

Loss of heterozygosity (LOH) was analyzed in four patients with endometrial hyperplasia (EH) with atypia (two patients) and without atypia (two patients) and in five patients with endometrial adenocarcinoma (EAC) to clarify the clinicopathologic relationship between genetic alterations and hormone therapy. Each patient was initially administered high-dose medroxyprogesterone acetate (MPA) as a uterine-sparing treatment. The five microsatellite markers used to analyze LOH were at chromosomal loci 8p22.1, 8p21, 8p21.3, 8p22, and 8p22. DNA was extracted from paraffin-embedded sections before, during, and after MPA therapy using laser capture microdissection. As a result, LOH was more frequently detected after MPA therapy (overall ratios were 16, 17, and 29% before, during, and after MPA therapy, respectively). LOH is more easily detected in EH loci than in EAC loci before MPA. For EAC, initial LOH detection on chromosome 8 may be related to an incomplete response to MPA, but negative LOH does not guarantee a favorable treatment outcome. For EH or atypical endometrial hyperplasia, it is unknown whether LOH alteration associated with MPA therapy is related to atypia of the disease.

Genomic aberrations in carcinomas of the uterine corpus

Endometrial carcinoma, the most common invasive neoplasm of the female genital tract, occurs either in a hormone-related, less virulent form (type I) or in a hormone-independent, more aggressive form (type II). Another cancer of the uterine corpus is carcinosarcoma, a biphasic or mixed epithelial-mesenchymal tumor, now classified as metaplastic carcinoma. We examined by karyotyping and comparative genomic hybridization a consecutive series of 67 endometrial carcinomas and 15 carcinosarcomas and compared the cytogenetic features of the different carcinoma subtypes. All three subtypes of uterine carcinoma had in common a nonrandom gain of material from 1q and 8q but differed from one another in other respects. Endometrial carcinomas of type I mostly presented gains from chromosome arms 1q and 8q and losses from Xp, 9p, 9q, 17p, 19p, and 19q, whereas endometrial carcinomas of type II showed a more complex imbalance picture, with gains from chromosome arms 1q, 2p, 3q, 5p, 6p, 7p, 8q, 10q, and 20q and losses from Xq, 5q, and 17p. The carcinosarcomas mostly showed gains of or from 1q, 5p, 8q, and 12q but losses from 9q, that is, they were much more similar to endometrial carcinomas in their pattern of acquired genomic changes than to sarcomas of the uterine corpus. It was also possible to identify different copy number changes among the different grades of type I carcinomas, between serous papillary and clear-cell carcinomas of type II, as well as between homologous and heterologous carcinosarcomas. Specifically, type I adenocarcinomas that were highly differentiated mostly showed gains from 1q and 10p; those that were moderately differentiated showed gains from 1q, 7p, 7q, and 10q as well as losses from Xp, 9p, 9q, 17p, 19p, and 19q; whereas those poorly differentiated showed gains from 1q, 2p, 2q, 3q, 6p, 8q, and 20q but losses from Xp, Xq, 5q, 9p, 9q, 17p, and 17q. The serous papillary carcinomas showed gains from 1q, 2p, 2q, 3q, 5p, 6p, 6q, 7p, 8q, 18q, 20p, and 20q but losses from 17p, whereas the clear-cell carcinomas showed gains from 3q, 7p, 8q, 10q, 16p, and 20q but losses from 6q. Finally, the homologous carcinosarcomas presented gains from 1p, 1q, 8q, 12q, and 17q as well as losses from 9q and 13q, whereas the heterologous tumors showed gains from 1q, 8p, and 8q. The reproducibility of the observed correlations between karyotypic aberration patterns and histological differentiation was underscored by the fact that those carcinosarcomas whose epithelial component resembled type I endometrial carcinomas also exhibiting a type I aberration profile, whereas carcinosarcomas with a type II carcinoma differentiation had karyotypic abnormalities similar to those of type II endometrial carcinomas.

Cyclin E dysregulation and chromosomal instability in endometrial cancer

Deregulation of cyclin E, an activator of cyclin-dependent kinase 2 (Cdk2), has been associated with a broad spectrum of human malignancies. Yet the mechanism linking abnormal cyclin E expression to carcinogenesis is largely unknown. The gene encoding the F-box protein hCdc4, a key component of the molecular machinery that targets cyclin E for degradation, is frequently mutated in endometrial cancer, leading to deregulation of cyclin E expression. Here we show that hCDC4 gene mutation and hyperphosphorylation of cyclin E, a parameter that usually correlates with hCDC4 mutation, have a strong statistically significant association with polypoidy and aneuploidy in endometrial cancer. On the contrary, elevated expression of cyclin E by itself was not significantly correlated with polyploidy or aneuploidy when tumors of similar grade are evaluated. These data suggest that impairment of cell cycle regulated proteolysis of cyclin E may be linked to carcinogenesis by promoting genomic instability.

Establishment and characterization of a poorly differentiated lethal human endometrial carcinoma cell line (NOU-1) with karyotype 46,XX

Immortal gynecologic cell lines, especially those of endometrial origin are diverse with multiple chromosomal alterations, making the study of origin and molecular genetic characteristics of such neoplasms difficult, if not impossible. We have established a new epithelial, poorly differentiated endometrial adenocarcinoma cell line (NOU-1) with a 46,XX chromosome complement. To confirm the tumor characteristics, we injected this cell line subcutaneously into the nude mouse. The tumor grown in vivo had the identical histology and the same 46,XX chromosome complement as the original tumor excised from the patient. The cells from the original tumor and those in the nude mouse shared the same characteristics with respect to histopathology, immunohistochemistry, steroid hormone receptor content, and growth characteristics. We report on the only established cell line of a highly aggressive, poorly differentiated endometrial adenocarcinoma with 46,XX chromosome complement where both estrogen and progesterone receptors are absent.

KIAA1096, a gene on chromosome 1q, is amplified and overexpressed in bladder cancer

Chromosomal gain on 1q23-24 is a cytogenetic finding found in approximately 30% of bladder tumors. Currently, no defined or candidate tumor-associated genes from this region have been identified. The objective of this study was to identify and quantitate the expression of putative cancer genes located at this chromosome locus in normal urothelium, superficial, and muscle invasive bladder tumors. We examined both normal and bladder cancer tissue specimens (N = 40-80 RNA, DNA, and protein) by semiquantitative RT/PCR, genomic PCR, and by Western blotting. The KIAA1096 gene is located at 1q23-24 with no overexpression or amplification in normal urothelium, but was significantly upregulated in 30% of tumors (P = 0.0001). There was a trend towards increased expression in invasive compared to superficial lesions (P = 0.06). A significant increase in gene copy was also found in a 38% of TCC of the bladder compared to normal bladder mucosa or peripheral blood lymphocytes. Immunohistochemistry (IHC) demonstrated KIAA1096 expression in nonmalignant bladder mucosa tissue but apparent upregulation in invasive transitional cell carcinoma. Two other genes, CH1 and RGS5, which are situated in the same region of chromosome 1q, demonstrated disparate patterns of expression. In summary, KIAA1096 is a gene situated at 1q23-24, which demonstrated a pattern of RNA and DNA expression consistent with the 38% expression of cytogenetic amplification noted on previous studies. This gene may, therefore, be a putative marker for this cytogenetic phenomenon and provide an opportunity to evaluate the clinical significance of previous cytogenetic findings.

Compilation of published comparative genomic hybridization studies

The power of comparative genomic hybridization (CGH) has been clearly proven since the first paper appeared in 1992 as a tool to characterize chromosomal imbalances in neoplasias. This review summarizes the chromosomal imbalances detected by CGH in solid tumors and in hemopathies. In May of 2001, we took a census of 430 articles providing information on 11,984 cases of human solid tumors or hematologic malignancies. Comparative generic hybridization has detected a number of recurrent regions of amplification or deletion that allows for identification of new chromosomal loci (oncogenes, tumor suppressor genes, or other genes) involved in the development, progression, and clonal evolution of tumors. When CGH data from different studies are combined, a pattern of nonrandom genetic aberrations appears. As expected, some of these gains and losses are common to different types of pathologies, while others are more tumor-specific.

Genetic alterations in endometrial hyperplasia and cancer

Putative precursors of endometrial cancer such as complex endometrial hyperplasia with atypia have been described to be monoclonal and considered to be genetically related. In order to identify a genetic marker that could serve as a putative predictor of endometrial cancer we analyzed 14 endometrial hyperplasia and 29 endometrial cancer samples for instabilities and loss of heterozygosity (LOH) in microsatellite sequences. Deletions on the short arm of chromosome 8 were frequently detected in both endometrial hyperplasia and cancer samples, suggesting that these deletions are early events in the development of endometrial cancer.

Analysis of genetic changes in rat endometrial carcinomas by means of comparative genomic hybridization

Animals of the BDII inbred rat strain are known to be genetically predisposed to endometrial adenocarcinoma (EAC). Using them as models of human EACs, we studied tumors arising in F1 and F2 progeny from BDII animals crossed to animals from two other inbred strains, in which EACs were quite rare. In order to identify chromosomal regions exhibiting DNA copy number changes, comparative genomic hybridization (CGH) was applied in a series corresponding to 27 different solid tumors, most of which were classified as EACs, from these animals. The main findings from the study were that, although many different chromosomes were involved in copy number variation, some of the changes detected were recurrent and quite specific. Among specific changes found were gains in rat chromosome (RNO) regions 4q12 approximately q22, 6q14 approximately q16, and whole chromosome arms in some of the small metacentric chromosomes (e.g., RNO14, 16, and 18). RNO10 was involved in gain in the terminal and proximal regions. Each of these regions contains previously identified cancer-related genes representing possible candidates to be involved in the development of EAC. Furthermore, it was observed that there were clear differences in the pattern of copy number changes between tumors occurring in the two different crosses, and also between solid tumors and cell cultures. Endometrial cancer is the most common human gynecological cancer, but not much is known about specific genetic changes influencing this disease. Two genetic alterations that have been reported from human endometrial cancer are amplification of the ERBB2 gene and mutations in the 12 codon of the KRAS gene. One case of Erbb2 amplification was found but there were no Kras mutations in the rat material studied. We conclude that molecular genetic analysis of the rat BDII model will provide important new information about EAC in mammals.

Genetic imbalances in precursor lesions of endometrial cancer detected by comparative genomic hybridization

Endometrial hyperplasia is regarded as a precursor lesion of endometrioid adenocarcinomas of the endometrium. The genetic events involved in the multistep process from normal endometrial glandular tissue to invasive endometrial carcinomas are primarily unknown. We chose endometrial hyperplasia as a model for identifying chromosomal aberrations occurring during carcinogenesis. Comparative genomic hybridization (CGH) was performed on 47 formalin-fixed, paraffin-embedded specimens of endometrial hyperplasia using the microdissection technique to increase the number of tumor cells in the samples and reduce contamination from normal cells. CGH analysis revealed that 24 out of 47 (51%) samples had detectable chromosomal imbalances, whereas 23 (49%) were in a genetically balanced state. The incidence of aberrant CGH profiles tended to parallel dysplasia grade, ranging from 22% aberrant profiles in simple hyperplasia to 67% in complex hyperplasia with atypia. The most frequent imbalances were 1p, 16p, and 20q underrepresentations and 4q overrepresentations. Copy number changes in 1p were more frequent in atypical complex hyperplasia than in complex lesions without atypical cells or simple lesions (42% versus 20% and 0%). Our results show that endometrial hyperplasia reveals recurrent chromosomal imbalances which tend to increase with the presence of atypical cells. The most frequent aberrations in endometrial cancer, 1q and 8q overrepresentations, are not present or are rare in its precursor lesions. This analysis provides evidence that tumorigenesis proceeds through the accumulation of a series of genetic alterations and suggests a stepwise mode of tumorigenesis.

Frequent c-myc and Int-2 overrepresentations in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a commonly occurring tumor in southern China. Although several causative factors have now been recognized, the genetic basis underlying its tumorigenesis is still unclear. To identify potential chromosomal aberrations for further investigations, comparative genomic hybridization (CGH) analysis was applied to the study of genomic imbalances in 10 NPC biopsy specimens. Before CGH analysis, the tumor cell content within the biopsy specimens was enriched by tissue microdissection, and universal genome amplification was performed on the recovered DNA. Recurrent chromosomal gains were detected on 1q (6 of 10 cases), 2q (5 of 10 cases), 3q (7 of 10 cases), 6p (8 of 10 cases), 6q (5 of 10 cases), 7q11.2 (4 of 10 cases), 8q (6 of 10 cases), 11q13, 12, and 15q (8 of 10 cases each), 17q (6 of 10 cases), and 20q (5 of 10 cases). Common losses were identified on 3p (5 of 10 cases), 9p (5 of 10 cases), 11q14-qter (8 of 10 cases), and 14q (5 of 10 cases). Among these aberrations, 7, 8, and 11 gains were further investigated on a series of NPC tissue samples, by interphase fluorescent in situ hybridization (FISH), for the incidence of alpha-satellites: 7, 8, and 11 c-myc and Int-2. Low-level increases of alpha-satellite 7 (9 of 34 cases; 26.5%), alpha-satellite 8 (15 of 34 cases; 44%), and alpha-satellite 11 (8 of 32 cases; 25%) were detected, whereas high-level copy gains of c-myc (21 of 34 cases; 62%) and Int-2 (26 of 34 cases; 76.5%) were more frequently found. Our series is the first to identify genomic overrepresentations of c-myc and Int-2 in NPC. The high incidence of Int-2 amplifications strongly suggests a role of this proto-oncogene in the pathogenesis of NPC.

Numerical abnormalities of chromosomes 1 and 10 in endometrial adenocarcinoma: fluorescence in situ hybridization analysis of 23 archival paraffin-embedded samples

Retrospective analysis of chromosomal changes in endometrial carcinoma was performed by fluorescence in situ hybridization on free nuclei isolated from formalin-fixed paraffin-embedded tissue. We examined 23 archival samples for numerical aberrations of chromosomes 1 and 10 with the use of specific DNA probes for the pericentromeric and centromeric regions of these two chromosomes. Numerical aberrations of chromosomes 1 and 10 were detected in 39% of the case analyzed, and the frequency of trisomy 10 tended to increase as the histological grade worsened. Our findings confirm the association of cytogenetic anomalies involving chromosomes 1 and 10 with endometrial carcinoma, as reported by other studies, and suggest that changes in centromere 10 copy number may correlate with the degree of tumor differentiation.

Chromosomal changes during progression of transitional cell carcinoma of the bladder and delineation of the amplified interval on chromosome arm 8q

The cascade of genetic alterations leading to malignant transformation has been described for adenocarcinoma of the colon but is not established for other common tumor entities. In the present study, different stages of transitional cell carcinoma (TCC) of the bladder are analyzed by comparative genomic hybridization. A dynamic pattern of the chromosomal changes during tumor progression is described. Deletion of chromosome arm 9q is the earliest genetic alteration in pTa tumors. In stage pT1 carcinomas, losses of 9q, 9p, and 11p and gain of 1q and 8q are the most common. In addition to the changes specific for earlier stages, gain of 5p and 20q becomes prominent in carcinomas stage > or =pT2. Association analysis reveals a remarkable cooccurrence of 9p deletion with gain of 5p and 20q in > or =pT2 tumors. In order to determine more precisely the size of the amplified segment and the degree of amplification on chromosome arm 8q in stage pT1 tumors, this region was analyzed by semiquantitative PCR using polymorphic microsatellite markers. These studies revealed an up to 13-fold amplification. The common region of amplification could be narrowed down to 8q22.3 and between GAAT1A4 and D8S1834 (about 7 cM).

Recent advances in the histopathology and molecular pathology of carcinoma of the endometrium

Endometrial carcinoma is the commonest malignancy of the female genital tract. The pathogenesis is complex and at least three pathogenetic subtypes exist with different prognostic implications. The molecular events involved remain poorly defined but several genes are involved and mutations of tp53, WAF1/CIP1, PTEN, bcl-2 and c-erbB-2 have been implicated. Although care is needed in interpreting the results, the majority of these mutations can be detected immunohistochemically and therefore have the potential to aid the pathologist and surgeon in assessing the prognosis of a tumour. However, for the time being, no molecular marker is as valuable in determining prognosis as conventional parameters such as tumour type, grade and vascular space involvement.