Dataset Information

The patterns and dynamics of genomic instability in metastatic pancreatic cancer.

ABSTRACT: Pancreatic cancer is an aggressive malignancy with a five-year mortality of 97-98%, usually due to widespread metastatic disease. Previous studies indicate that this disease has a complex genomic landscape, with frequent copy number changes and point mutations, but genomic rearrangements have not been characterized in detail. Despite the clinical importance of metastasis, there remain fundamental questions about the clonal structures of metastatic tumours, including phylogenetic relationships among metastases, the scale of ongoing parallel evolution in metastatic and primary sites, and how the tumour disseminates. Here we harness advances in DNA sequencing to annotate genomic rearrangements in 13 patients with pancreatic cancer and explore clonal relationships among metastases. We find that pancreatic cancer acquires rearrangements indicative of telomere dysfunction and abnormal cell-cycle control, namely dysregulated G1-to-S-phase transition with intact G2-M checkpoint. These initiate amplification of cancer genes and occur predominantly in early cancer development rather than the later stages of the disease. Genomic instability frequently persists after cancer dissemination, resulting in ongoing, parallel and even convergent evolution among different metastases. We find evidence that there is genetic heterogeneity among metastasis-initiating cells, that seeding metastasis may require driver mutations beyond those required for primary tumours, and that phylogenetic trees across metastases show organ-specific branches. These data attest to the richness of genetic variation in cancer, brought about by the tandem forces of genomic instability and evolutionary selection.

SUBMITTER: Campbell PJ

PROVIDER: S-EPMC3137369 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The patterns and dynamics of genomic instability in metastatic pancreatic cancer.

Campbell Peter J PJ Yachida Shinichi S Mudie Laura J LJ Stephens Philip J PJ Pleasance Erin D ED Stebbings Lucy A LA Morsberger Laura A LA Latimer Calli C McLaren Stuart S Lin Meng-Lay ML McBride David J DJ Varela Ignacio I Nik-Zainal Serena A SA Leroy Catherine C Jia Mingming M Menzies Andrew A Butler Adam P AP Teague Jon W JW Griffin Constance A CA Burton John J Swerdlow Harold H Quail Michael A MA Stratton Michael R MR Iacobuzio-Donahue Christine C Futreal P Andrew PA

Nature 20101001 7319

Pancreatic cancer is an aggressive malignancy with a five-year mortality of 97-98%, usually due to widespread metastatic disease. Previous studies indicate that this disease has a complex genomic landscape, with frequent copy number changes and point mutations, but genomic rearrangements have not been characterized in detail. Despite the clinical importance of metastasis, there remain fundamental questions about the clonal structures of metastatic tumours, including phylogenetic relationships am ...[more]

PMID: 20981101

Similar Datasets

Project description:Genetic instability, a hallmark feature of human cancers including prostatic adenocarcinomas, is considered a driver of metastasis. Somatic copy number alterations (CNA) are found in most aggressive primary human prostate cancers, and the overall number of such changes is increased in metastases. Chromosome 10q23 deletions, encompassing PTEN, and amplification of 8q24, harboring MYC, are frequently observed, and the presence of both together portends a high risk of prostate cancer-specific mortality. In extant genetically engineered mouse prostate cancer models (GEMM), isolated MYC overexpression or targeted Pten loss can each produce early prostate adenocarcinomas, but are not sufficient to induce genetic instability or metastases with high penetrance. Although a previous study showed that combining Pten loss with focal MYC overexpression in a small fraction of prostatic epithelial cells exhibits cooperativity in GEMMs, additional targeted Tp53 disruption was required for formation of metastases. We hypothesized that driving combined MYC overexpression and Pten loss using recently characterized Hoxb13 transcriptional control elements that are active in prostate luminal epithelial cells would induce the development of genomic instability and aggressive disease with metastatic potential. Neoplastic lesions that developed with either MYC activation alone (Hoxb13-MYC) or Pten loss alone (Hoxb13-Cre∣Pten(Fl/Fl)) failed to progress beyond prostatic intraepithelial neoplasia and did not harbor genomic CNAs. By contrast, mice with both alterations (Hoxb13-MYC∣Hoxb13-Cre∣Pten(Fl/Fl), hereafter, BMPC mice) developed lethal adenocarcinoma with distant metastases and widespread genome CNAs that were independent of forced disruption of Tp53 and telomere shortening. BMPC cancers lacked neuroendocrine or sarcomatoid differentiation, features uncommon in human disease but common in other models of prostate cancer that metastasize. These data show that combined MYC activation and Pten loss driven by the Hoxb13 regulatory locus synergize to induce genomic instability and aggressive prostate cancer that phenocopies the human disease at the histologic and genomic levels.

Project description:PURPOSE:Few population studies have examined patterns of systemic therapy administration in metastatic pancreatic cancer (MPC) or the predictors associated with specific treatment choices. PATIENTS AND METHODS:We assessed 4,011 consecutive MPC patients who received chemotherapy between January 2005 and December 2015 at academic, private, and community-based oncology practices subscribing to a U.S.-wide chemotherapy order entry system capturing disease, patient, provider, and treatment data. Multivariate analyses of these prospectively recorded characteristics identified significant predictors of specific therapeutic choices. RESULTS:Overall, 100 different regimens were used in first-line treatment of MPC. First-line gemcitabine monotherapy usage fell steadily from 72% in 2006 to 16% in 2015. This steep decline mirrored increases in first-line usage of both 5 fluorouracil, leucovorin, irinotecan and oxaliplatin (FOLFIRINOX) and gemcitabine?+?nab-paclitaxel. Younger male patients were more likely to receive FOLFIRINOX as first-line treatment, whereas patients treated at community practices and by oncologists with lower MPC patient volume were more likely to receive gemcitabine plus nab-paclitaxel (all p???.05). Among all patients receiving first-line chemotherapy for MPC, 49% went on to receive second-line therapy and 19% received third-line therapy; administration of second- and third-line therapies increased steadily over the time course of follow-up. Younger patients and those treated by oncologists with higher MPC patient volume were more likely to receive second- and third-line therapies. CONCLUSION:This population-based study provides insight into treatment patterns of MPC in the U.S. Usage patterns varied greatly according to patient and provider characteristics. IMPLICATIONS FOR PRACTICE:This study examined real world metastatic pancreatic cancer treatment patterns in the United States with the goals of understanding changes in chemotherapy treatment frequencies over time and determining the individual predictors that underlie the chemotherapy choices oncologists make for their patients. Our data set is unique in that it captured not only patient-level data, but also oncologist-level data. It also captured data from private and community practices as well as academic centers. To our knowledge, this is the only data set that can give this degree of insight into oncologist decision making practices.

Dataset Information

The patterns and dynamics of genomic instability in metastatic pancreatic cancer.

Publications

The patterns and dynamics of genomic instability in metastatic pancreatic cancer.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets