Connie Eaves | University of British Columbia (original) (raw)

Papers by Connie Eaves

(A) Correlation between the total number of cells retrieved from individually assessed 7... more (A) Correlation between the total number of cells retrieved from individually assessed 7-d cultures with the corresponding number of CFCs detected. (B) Distribution of clonal CFC outputs in 7-d cultures initiated with different types of input cells. The dotted line indicates the median values of positive clones: 1,000 for clones derived from basal adult cells (n = 44), 140 for clones from CD61+ adult luminal cells (n = 35), and 13,000 for clones from fetal cells (n = 55). (C) Comparison of MRU outputs determined by LDA in 7-d Matrigel cultures initiated with single adult and fetal mammary cells. The value for fetal cells is significantly higher than either of the adult values (p<0.01, Chi-square p value, pair-wise comparison of stem cell frequencies, ELDA, <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001630#pbio.1001630.s009" target="_blank">Table S7</a>).</p

Blood, 2008

The chronic phase of CML is sustained by rare BCR-ABL+ stem cells. These cells share many propert... more The chronic phase of CML is sustained by rare BCR-ABL+ stem cells. These cells share many properties with normal pluripotent hematopoietic stem cells, but also differ in critical ways that alter their growth, drug responsiveness and genome stability. Understanding the molecular mechanisms underlying the biological differences between normal and CML stem cells is key to the development of more effective CML therapies. To obtain new insights into these mechanisms, we generated Long Serial Analysis of Gene Expression (SAGE) libraries from paired isolates of highly purified lin-CD34+CD45RA-CD36- CD71-CD7-CD38+ and lin-CD34+CD45RA-CD36-CD71-CD7-CD38- cells from 3 chronic phase CML patients (all with predominantly Ph+/BCR-ABL+ cells in both subsets) and from 3 control samples: a pool of 10 normal bone marrows (BMs), a single normal BM and a pool of G-CSF-mobilized blood cells from 9 donors. In vitro bioassays showed the CD34+CD38+ cells were enriched in CFCs (CML: 3–20% pure; normal: 4–19...

Blood, 2013

Genetic instability is a hallmark of chronic myeloid leukemia (CML). Recently, several major abno... more Genetic instability is a hallmark of chronic myeloid leukemia (CML). Recently, several major abnormalities in DNA repair mechanisms have been identified in primitive CML cells that likely explain the additional mutations these cells develop leading to their selective growth under tyrosine kinase inhibitor (TKI) therapies. It seems likely that such mechanisms also underlie disease progression in CML. However, an understanding of the specific somatic mutations involved and investigations of their resulting effects on the biological behavior of primary sources of primitive chronic phase (CP) CML cells is extremely challenging. As an alternative approach, we have now explored the possibility of applying whole genome sequencing (WGS) to induced pluripotent stem cells (iPSCs) derived from primitive CML cells to determine if such iPSCs, genocopy the mutations present in the diagnostic sample from which they were generated and whether primitive hematopoietic cells derived from these iPSCs m...

Shared mechanisms driving the malignant properties of human breast cancers have been difficult to... more Shared mechanisms driving the malignant properties of human breast cancers have been difficult to identify because of their extensive biological and molecular heterogeneity. Here we sought to examine the possibility that mammalian Y-box binding protein-1 (YB-1) might have such a role given its association with poor survival in patients with other types of metastatic tumours1,2 and recently reported ability in high-risk sarcomas to induce a hypoxia-inducible factor 1α (HIF1α) response3 and stress granule formation through translational activation of G3BP1 mRNAs4. However, the role of YB-1 in contributing to the malignant properties of human breast cancer cells in vivo has not been experimentally investigated. Here we demonstrate a critical co-operative role of YB-1 in mediating the initial as well as later malignant properties and downstream activities displayed by de novo transformed normal human mammary cells as well as by an established aggressive breast cancer cell line in transp...

Mature blood cells derive from primitive cells through a complex and poorly understood process th... more Mature blood cells derive from primitive cells through a complex and poorly understood process that involves an interplay of transcription factors and epigenetic modifications. We now show that multiple human hematopoietic progenitor phenotypes display a common repressive H3K27me3 signature (R>0.97) together with their mature lymphoid, but not their differentiated monocyte and erythroid progeny. This signature includes many large organized H3K27me3 domains that we also show are required for the production of differentiating lymphoid cells. These results reveal H3K27me3 contraction to play a previously unknown intermediate step in differentially regulating the activation of terminal differentiation programs in normal human lymphoid and myeloid progenitors.

The EMBO Journal, 2019

The mammary gland in adult women consists of biologically distinct cell types that differ in thei... more The mammary gland in adult women consists of biologically distinct cell types that differ in their surface phenotypes. Isolation and molecular characterization of these subpopulations of mammary cells have provided extensive insights into their different transcriptional programs and regulation. This information is now serving as a baseline for interpreting the heterogeneous features of human breast cancers. Examination of breast cancer mutational profiles further indicates that most have undergone a complex evolutionary process even before being detected. The consequent intra-tumoral as well as inter-tumoral heterogeneity of these cancers thus poses major challenges to deriving information from early and hence likely pervasive changes in potential therapeutic interest. Recently described reproducible and efficient methods for generating human breast cancers de novo in immunodeficient mice transplanted with genetically altered primary cells now offer a promising alternative to investigate initial stages of human breast cancer development. In this review, we summarize current knowledge about key transcriptional regulatory processes operative in these partially characterized subpopulations of normal human mammary cells and effects of disrupting these processes in experimentally produced human breast cancers.

Stem cells and development, Jan 20, 2018

Cellular barcoding is a powerful tool for analyzing the clonal outputs of large numbers of co-tra... more Cellular barcoding is a powerful tool for analyzing the clonal outputs of large numbers of co-transplanted cells. The extensive growth and bi-lineage differentiation potential of transplanted basal cells isolated from the normal adult female mouse mammary gland is well established, but analyses of similarly performed luminal cell transplants have been limited due to their more restricted outputs. Here we report detecting macroscopic, branched gland structures 8 weeks after transplanting approximately 105 purified, barcoded EpCAM++CD49flow luminal cells into a cleared fat pad in two syngeneic mice. DNA sequencing revealed 23 clones of variable size and composition. Notably, these included 10 bi-lineage clones, that were ~10 times larger than either the 5 basal and 8 luminal clones also present. These results support the ability of rare luminal cells to produce both single and bi-lineage clones when stimulated to do ...

Breast Cancer Research, 2006

Background Epidemiological studies have shown that only about 20% of the familial clustering of b... more Background Epidemiological studies have shown that only about 20% of the familial clustering of breast cancer is explained by the known highly penetrant mutations in BRCA1 and BCRA2. We have set out to search for the genes for the remaining 80%. Twin studies indicate a predominant role of shared genes rather than a shared environment; the patterns of occurrence of breast cancer in families are consistent with a major polygenic component. Methods We have assembled a population based set of 5,000 breast cancer cases and 5,000 controls from the East Anglian population. We have simple clinical and epidemiological information, including family history, and samples of blood and paraffin embedded tumour. We have used association studies based on single nucleotide polymorphisms, first with candidate genes and then in a genome-wide scan of 266,000 single nucleotide polymorphisms, to search for the putative predisposing genes. We have as yet searched only for common variants (frequency >5%). Results We have modelled the effects of polygenic predisposition in the East Anglian population, and have shown that the model predicts a wide distribution of individual risk in the population, such that half of all breast cancers may occur in the 12% of women at greatest risk. Both the candidate gene-based and genome-wide scans have provided provisional identification of a number of novel susceptibility genes, and these are currently being confirmed by a worldwide consortium of independent laboratories totalling 20,000-plus cases and controls. No single gene so far identified contributes more than 2% of the total inherited component, consistent with a model in which susceptibility is the result of a large number of individually small genetic effects. S2 Translating breast cancer research into clinical practice-new approaches and better outcomes

Stem cell reports, Jan 27, 2015

Human palatine tonsils are oropharyngeal lymphoid tissues containing multiple invaginations (cryp... more Human palatine tonsils are oropharyngeal lymphoid tissues containing multiple invaginations (crypts) in which the continuity of the outer surface epithelium is disrupted and the isolated epithelial cells intermingle with other cell types. We now show that primitive epithelial cells detectable in vitro in 2D colony assays and in a 3D culture system are CD44(+)NGFR(+) and present in both surface and crypt regions. Transcriptome analysis indicated a high similarity between CD44(+)NGFR(+) cells in both regions, although those isolated from the crypt contained a higher proportion of the most primitive (holo)clonogenic cells. Lentiviral transduction of CD44(+)NGFR(+) cells from both regions with human papillomavirus 16-encoded E6/E7 prolonged their growth in 2D cultures and caused aberrant differentiation in 3D cultures. Our findings therefore reveal a shared, site-independent, hierarchical organization, differentiation potential, and transcriptional profile of normal human tonsillar epit...

Cancer Research, 2013

Reactive oxygen species (ROS) are known mediators of DNA damage and likely contributors to oncoge... more Reactive oxygen species (ROS) are known mediators of DNA damage and likely contributors to oncogenesis. However, very little is known about the mechanisms controlling ROS in the cells that make up the normal human mammary gland, in spite of its being a major site of cancer development. To investigate how ROS are generated and their potential role in two functionally distinct, primitive normal human mammary epithelial cell compartments (luminal and basal), we isolated these subsets at high purities by FACS and compared the levels within them of ROS, components that positively and negatively regulate ROS, their responses to oxidative stressors and evidence of ROS-associated DNA damage. The results show that purified progenitors of the cells that line the gland lumen (defined by their EpCAM+ CD49f+ phenotype) contain significantly higher levels of superoxide (O2*) anions and H2O2 than the basal cells (defined as EpCAMlow/- CD49fhigh cells and highly enriched in bipotent progenitors and...

Experimental Hematology, 2014

Haematopoietic stem cells (HSCs) traffic between bone marrow and circulation, what allows for lif... more Haematopoietic stem cells (HSCs) traffic between bone marrow and circulation, what allows for life-saving clinical transplantation. Our previous work has shown that HSC numbers in blood are regulated by the central pacemaker in the brain, which reaches bone marrow nestin + mesenchymal stem cells through peripheral nerves. Contrarily to what it was believed, we have found recently that HSC-niche mesenchymal stem cells are different from those that form the skeleton and share instead a common origin with peripheral nerves and supporting glial cells. Thus, tight regulation of the bone marrow stem-cell niche in vertebrates builds upon developmental relationships of its cellular components. Moreover, we have shown that damage to this regulatory network is essential for the manifestation of myeloproliferative neoplasms, diseases that were previously thought to be driven solely by mutated HSCs. Also, JAK inhibitors (blocking the most frequent HSC mutation found in myeloproliferative neoplasms) cannot eradicate leukaemic stem cells. Our recent data has uncovered a selective regulation of normal and leukaemic haematopoietic progenitor maintenance, survival and proliferation by sex hormones. These results might explain gender differences in blood cancer incidence and offer a new way of targeting leukaemic stem cells with clinically approved drugs. Nevertheless, we anticipate that the ideal future treatment for myeloproliferative diseases should target both leukaemic stem cells and their microenvironment. We will present candidate future strategies based on novel neuroendocrine regulatory pathways of bone marrow stem cells.

Stem Cells, 2013

A patient with βE/β0-thalassemia major was converted to transfusion-independence 4.5 years ago by... more A patient with βE/β0-thalassemia major was converted to transfusion-independence 4.5 years ago by lentiviral gene transfer in hematopoietic stem cells while showing a myeloid-biased cell clone. Induced pluripotent stem cells (iPSCs) are a potential alternative source of hematopoietic stem cells. If fetal to adult globin class, switching does not occur in vivo in iPSC-derived erythroid cells, β-globin gene transfer would be unnecessary. To investigate both vector integration skewing and the potential use of iPSCs for the treatment of thalassemia, we derived iPSCs from the thalassemia gene therapy patient and compared iPSC-derived hematopoietic cells to their natural isogenic somatic counterparts. In NSG immunodeficient mice, embryonic to fetal and a partial fetal to adult globin class switching were observed, indicating that the gene transfer is likely necessary for iPSC-based therapy of the β-hemoglobinopathies. Lentivector integration occurred in regions of low and high genotoxicit...

Nature Reviews Cancer, 2012

The cancer stem cell (CSC) concept derives from the fact that cancers are dysregulated tissue clo... more The cancer stem cell (CSC) concept derives from the fact that cancers are dysregulated tissue clones whose continued propagation is vested in a biologically distinct subset of cells that are typically rare. This idea is not new, but has recently gained prominence because of advances in defining normal tissue hierarchies, a greater appreciation of the multistep nature of oncogenesis and improved methods to propagate primary human cancers in immunodeficient mice. As a result we have obtained new insights into why the CSC concept is not universally applicable, as well as a new basis for understanding the complex evolution, phenotypic heterogeneity and therapeutic challenges of many human cancers.

Nature Cell Biology, 2014

Heterogeneity in tumour cell properties underlies many treatment failures. Understanding the sour... more Heterogeneity in tumour cell properties underlies many treatment failures. Understanding the sources of such heterogeneity has proved to be challenging, but remains critical to improving patient outcomes. Integrin α(v)β₃ expression in multiple types of solid tumour stem cells is now shown to control a pro-survival pathway that contributes to therapy resistance.

Nature Cell Biology, 2013

Mouse haematopoietic stem cells (HSCs) undergo a postnatal transition in several properties, incl... more Mouse haematopoietic stem cells (HSCs) undergo a postnatal transition in several properties, including a marked reduction in their self-renewal activity. We now show that the developmentally timed change in this key function of HSCs is associated with their decreased expression of Lin28b and an accompanying increase in their let-7 microRNA levels. Lentivirus-mediated overexpression of Lin28 in adult HSCs elevates their self-renewal activity in transplanted irradiated hosts, as does overexpression of Hmga2, a well-established let-7 target that is upregulated in fetal HSCs. Conversely, HSCs from fetal Hmga2 −/− mice do not exhibit the heightened self-renewal activity that is characteristic of wild-type fetal HSCs. Interestingly, overexpression of Hmga2 in adult HSCs does not mimic the ability of elevated Lin28 to activate a fetal lymphoid differentiation program. Thus, Lin28b may act as a master regulator of developmentally timed changes in HSC programs with Hmga2 serving as its specific downstream modulator of HSC self-renewal potential.