Share icon Three circles with dashes Person icon Man with pen You Tube Logo Just "You tube" text Facebook logo Small letter f Search icon Magnifier Twitter logo Simplified small bird Email icon Envelope
Skip to main
Scientist working in a laboratory and plants

Genetic and Phenotypic Diversity in Breast Tumor Metastases

Metastatic disease is the main cause of cancer-related mortality due to almost universal therapeutic resistance

Scientist working in a laboratory and plants

Scientist in laboratory examinates samples and chemical fluids.

Authors:
Vanessa Almendro, Hee Jung Kim, Yu-Kang Cheng, Mithat Gönen, Shalev Itzkovitz, Pedram Argani, Alexander van Oudenaarden, Saraswati Sukumar, Franziska Michor and Kornelia Polyak

Affiliations:
Departments of Medical Oncology and Biostatistics and Computational Biology, Dana-Farber Cancer Institute; Department of Medicine, Brigham and Women’s Hospital; Department of Medicine, Harvard Medical School; Department of Biostatistics, Harvard School of Public Health, Boston; Departments of Physics and Biology, Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology; Harvard Stem Cell Institute, Cambridge, Massachusetts; Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York; Departments of Pathology and Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Medical Oncology, Hospital Clinic, Institut d’Investigacions Biomediques August Pi i Sunyer, Barcelona, Spain; Department of Pathology, MizMedi Hospital, Seoul, South Korea; Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel; and Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Center Utrecht, Utrecht, the Netherlands

Abstract:
Metastatic disease is the main cause of cancer-related mortality due to almost universal therapeutic resistance. Despite its high clinical relevance, our knowledge of how cancer cell populations change during metastatic progression is limited. Here, we investigated intratumor genetic and phenotypic heterogeneity during metastatic progression of breast cancer. We analyzed cellular genotypes and phenotypes at the single cell level by performing immunoFISH in intact tissue sections of distant metastatic tumors from rapid autopsy cases and from primary tumors and matched lymph node metastases collected before systemic therapy. We calculated the Shannon index of intratumor diversity in all cancer cells and within phenotypically distinct cell populations. We found that the extent of intratumor genetic diversity was similar regardless of the chromosomal region analyzed, implying that it may reflect an inherent property of the tumors. We observed that genetic diversity was highest in distant metastases and was generally concordant across lesions within the same patient, whereas treatment-naïve primary tumors and matched lymph node metastases were frequently genetically more divergent. In contrast, cellular phenotypes were more discordant between distant metastases than primary tumors and matched lymph node metastases. Diversity for 8q24 was consistently higher in HER2+ tumors compared with other subtypes and in metastases of triple-negative tumors relative to primary sites. We conclude that our integrative method that couples ecologic models with experimental data in human tissue samples could be used for the improved prognostication of patients with cancer and for the design of more effective therapies for progressive disease.Cancer Res; 74(5); 1338–48. ©2014 AACR.

Full article

____________________________________________________________________________________________________________________________

Israel BDS – building dialogue through science – aims to promote the kind of international collaboration that can lead to true understanding between people. Israel BDS stands for the free and open exchange of ideas among scientists everywhere. By reporting on the benefits of Israeli-international scientific research and the web of connections that these scientists create around the world, Israel BDS takes a vibrant approach to highlighting the global necessity of continued international scientific collaboration.

___________________________________________________________________________________________________________________________