Carolina Digital Repository (University of North Carolina at Chapel Hill), 2021
The most common events in breast cancer (BC) involve chromosome arm losses and gains. Here we des... more The most common events in breast cancer (BC) involve chromosome arm losses and gains. Here we describe identification of 1089 gene-centric common insertion sites (gCIS) from transposon-based screens in 8 mouse models of BC. Some gCIS are driver-specific, others driver non-specific, and still others associated with tumor histology. Processes affected by driver-specific and histology-specific mutations include well-known cancer pathways. Driver non-specific gCIS target the Mediator complex, Ca ++ signaling, Cyclin D turnover, RNAmetabolism among other processes. Most gCIS show single allele disruption and many map to genomic regions showing high-frequency hemizygous loss in human BC. Two gCIS, Nf1 and Trps1, show synthetic haploinsufficient tumor suppressor activity. Many gCIS act on the same pathway responsible for tumor initiation, thereby selecting and sculpting just enough and just right signaling. These data highlight~1000 genes with predicted conditional haploinsufficient tumor suppressor function and the potential to promote chromosome arm loss in BC.
Metastatic breast-cancer is a major cause of death in women worldwide, yet the relationship betwe... more Metastatic breast-cancer is a major cause of death in women worldwide, yet the relationship between oncogenic drivers that promote metastatic versus primary cancer is still contentious. To elucidate this relationship in treatmentnaive animals, we hereby describe mammary-specific transposon-mutagenesis screens in female mice together with loss-of-function Rb, which is frequently inactivated in breast-cancer. We report gene-centric common insertion-sites (gCIS) that are enriched in primary-tumors, in metastases or shared by both compartments. Shared-gCIS comprise a major MET-RAS network, whereas metastasis-gCIS form three additional hubs: Rho-signaling, Ubiquitination and RNA-processing. Pathway analysis of four clinical cohorts with paired primarytumors and metastases reveals similar organization in human breast-cancer with subtype-specific shared-drivers (e.g. RB1-loss, TP53-loss, high MET, RAS, ER), primary-enriched (EGFR, TGFβ and STAT3) and metastasis-enriched (RHO, PI3K) oncogenic signaling. Inhibitors of RB1-deficiency or MET plus RHO-signaling cooperate to block cell migration and drive tumor cell-death. Thus, targeting shared-and metastasis-but not primary-enriched derivers offers a rational avenue to prevent metastatic breast-cancer. Metastatic dissemination is the major cause of death from diverse types of cancers including those of the breast and is the target of emerging therapeutic strategies 1-4. In the United States for example, 6% of women exhibit metastatic breast cancer at initial diagnosis, 12.7% develop invasive breast cancer each year, and 15% succumb to the disease (https://www.cancer.net/cancer-types/breast-cancermetastatic/statistics). In contrast, primary tumors, the focus of many therapies, are commonly removed and discarded. The oncogenic relationship between primary and metastatic lesions is therefore critical for judicial therapy, yet it is highly contentious. One model posits that the oncogenic alterations that drive primary tumor growth also propel metastatic dissemination 5. Indeed, multiple studies show that oncogenes and tumor suppressors that induce primary tumor growth also promote metastasis [reviewed in ref. 6], and this is further supported by the high concordance between the oncogenic landscape of metastases and primary lesions from the same patients [ref. 7. and references therein]. Other reports highlight new alterations in metastatic versus primary lesions 8-15. Such metastatic-specific alterations may contribute to the cellular plasticity required for the metastatic cascade 6 , but may also reflect selective pressure and emergence of rare clones that survive therapy 16,17. Thus, the exact correlation between oncogenic drivers
This is an open-access article distributed under the terms of the Creative Commons Attribution Li... more This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
(log-rank) method. Differences between values were considered statistically significant at a P va... more (log-rank) method. Differences between values were considered statistically significant at a P value of less than 0.05. TIC frequency was estimated by Poisson distribution using L-Calc Software, version 1.1.1 (STEMCELL Technologies). All data represent SD.
Aberrant activation of Notch receptors has been shown to cause mammary tumors in mice. We therefo... more Aberrant activation of Notch receptors has been shown to cause mammary tumors in mice. We therefore used in situ hybridization to analyze expression of Notch ligands and receptors in human breast cancer. High levels of JAG1 and NOTCH1 were noted in a subset of tumors with poor prognosis pathologic features (P < 0.05). We therefore used tissue microarrays to analyze the expression of these genes in a collection of breast cancers from patients representing a wide spectrum of clinical stages, and from whom associated followup survival data was available (n = 184). Patients with tumors expressing high levels of JAG1 or NOTCH1 had a significantly poorer overall survival compared with patients expressing low levels of these genes [5-year survival rate of 42% versus 65% and median survival of 50 versus 83 months, respectively, for JAG1 Hi vs. Lo (P = 0.01); 49% versus 64% and 53 versus 91 months, respectively, for NOTCH1 Hi vs. Lo (P = 0.02)]. Moreover, a synergistic effect of high-level JAG1 and high-level NOTCH1 coexpression on overall survival was observed (5-year survival rate of 32% and median survival of 40 months; P = 0.003). These data (a) identify novel prognostic markers for breast cancer, (b) suggest a mechanism whereby Notch is activated in aggressive breast tumors, and (c) may identify a signaling pathway activated in poor prognosis breast cancer which can be therapeutically targeted.
Supplementary Figure 2 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 2 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 1 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 1 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 4 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 4 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 9 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 9 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 1. Generation of the Mfng mutant mice and expression analysis of Mfng in the... more Supplementary Figure 1. Generation of the Mfng mutant mice and expression analysis of Mfng in the mouse mammary gland
Supplementary Figure 5 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 5 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 6 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 6 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Table 1. A list of top 200 differentially expressed genes in xenografts from inject... more Supplementary Table 1. A list of top 200 differentially expressed genes in xenografts from injection of shMFNG MDA-MB231 cells vs. control MDA-MB231 cells
Supplementary Information. Including Supplementary Figure Legends, Supplementary Methods, and Sup... more Supplementary Information. Including Supplementary Figure Legends, Supplementary Methods, and Supplementary References.
Supplementary Figure 3 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 3 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 4. Pharmacological inhibition of PI3Kγ has no effect on proliferation of MDA... more Supplementary Figure 4. Pharmacological inhibition of PI3Kγ has no effect on proliferation of MDA-MB231 cells, but shows an inhibitory effect on C0321 cells.
Supplementary Figure 8 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 8 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Carolina Digital Repository (University of North Carolina at Chapel Hill), 2021
The most common events in breast cancer (BC) involve chromosome arm losses and gains. Here we des... more The most common events in breast cancer (BC) involve chromosome arm losses and gains. Here we describe identification of 1089 gene-centric common insertion sites (gCIS) from transposon-based screens in 8 mouse models of BC. Some gCIS are driver-specific, others driver non-specific, and still others associated with tumor histology. Processes affected by driver-specific and histology-specific mutations include well-known cancer pathways. Driver non-specific gCIS target the Mediator complex, Ca ++ signaling, Cyclin D turnover, RNAmetabolism among other processes. Most gCIS show single allele disruption and many map to genomic regions showing high-frequency hemizygous loss in human BC. Two gCIS, Nf1 and Trps1, show synthetic haploinsufficient tumor suppressor activity. Many gCIS act on the same pathway responsible for tumor initiation, thereby selecting and sculpting just enough and just right signaling. These data highlight~1000 genes with predicted conditional haploinsufficient tumor suppressor function and the potential to promote chromosome arm loss in BC.
Metastatic breast-cancer is a major cause of death in women worldwide, yet the relationship betwe... more Metastatic breast-cancer is a major cause of death in women worldwide, yet the relationship between oncogenic drivers that promote metastatic versus primary cancer is still contentious. To elucidate this relationship in treatmentnaive animals, we hereby describe mammary-specific transposon-mutagenesis screens in female mice together with loss-of-function Rb, which is frequently inactivated in breast-cancer. We report gene-centric common insertion-sites (gCIS) that are enriched in primary-tumors, in metastases or shared by both compartments. Shared-gCIS comprise a major MET-RAS network, whereas metastasis-gCIS form three additional hubs: Rho-signaling, Ubiquitination and RNA-processing. Pathway analysis of four clinical cohorts with paired primarytumors and metastases reveals similar organization in human breast-cancer with subtype-specific shared-drivers (e.g. RB1-loss, TP53-loss, high MET, RAS, ER), primary-enriched (EGFR, TGFβ and STAT3) and metastasis-enriched (RHO, PI3K) oncogenic signaling. Inhibitors of RB1-deficiency or MET plus RHO-signaling cooperate to block cell migration and drive tumor cell-death. Thus, targeting shared-and metastasis-but not primary-enriched derivers offers a rational avenue to prevent metastatic breast-cancer. Metastatic dissemination is the major cause of death from diverse types of cancers including those of the breast and is the target of emerging therapeutic strategies 1-4. In the United States for example, 6% of women exhibit metastatic breast cancer at initial diagnosis, 12.7% develop invasive breast cancer each year, and 15% succumb to the disease (https://www.cancer.net/cancer-types/breast-cancermetastatic/statistics). In contrast, primary tumors, the focus of many therapies, are commonly removed and discarded. The oncogenic relationship between primary and metastatic lesions is therefore critical for judicial therapy, yet it is highly contentious. One model posits that the oncogenic alterations that drive primary tumor growth also propel metastatic dissemination 5. Indeed, multiple studies show that oncogenes and tumor suppressors that induce primary tumor growth also promote metastasis [reviewed in ref. 6], and this is further supported by the high concordance between the oncogenic landscape of metastases and primary lesions from the same patients [ref. 7. and references therein]. Other reports highlight new alterations in metastatic versus primary lesions 8-15. Such metastatic-specific alterations may contribute to the cellular plasticity required for the metastatic cascade 6 , but may also reflect selective pressure and emergence of rare clones that survive therapy 16,17. Thus, the exact correlation between oncogenic drivers
This is an open-access article distributed under the terms of the Creative Commons Attribution Li... more This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
(log-rank) method. Differences between values were considered statistically significant at a P va... more (log-rank) method. Differences between values were considered statistically significant at a P value of less than 0.05. TIC frequency was estimated by Poisson distribution using L-Calc Software, version 1.1.1 (STEMCELL Technologies). All data represent SD.
Aberrant activation of Notch receptors has been shown to cause mammary tumors in mice. We therefo... more Aberrant activation of Notch receptors has been shown to cause mammary tumors in mice. We therefore used in situ hybridization to analyze expression of Notch ligands and receptors in human breast cancer. High levels of JAG1 and NOTCH1 were noted in a subset of tumors with poor prognosis pathologic features (P < 0.05). We therefore used tissue microarrays to analyze the expression of these genes in a collection of breast cancers from patients representing a wide spectrum of clinical stages, and from whom associated followup survival data was available (n = 184). Patients with tumors expressing high levels of JAG1 or NOTCH1 had a significantly poorer overall survival compared with patients expressing low levels of these genes [5-year survival rate of 42% versus 65% and median survival of 50 versus 83 months, respectively, for JAG1 Hi vs. Lo (P = 0.01); 49% versus 64% and 53 versus 91 months, respectively, for NOTCH1 Hi vs. Lo (P = 0.02)]. Moreover, a synergistic effect of high-level JAG1 and high-level NOTCH1 coexpression on overall survival was observed (5-year survival rate of 32% and median survival of 40 months; P = 0.003). These data (a) identify novel prognostic markers for breast cancer, (b) suggest a mechanism whereby Notch is activated in aggressive breast tumors, and (c) may identify a signaling pathway activated in poor prognosis breast cancer which can be therapeutically targeted.
Supplementary Figure 2 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 2 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 1 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 1 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 4 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 4 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 9 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 9 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 1. Generation of the Mfng mutant mice and expression analysis of Mfng in the... more Supplementary Figure 1. Generation of the Mfng mutant mice and expression analysis of Mfng in the mouse mammary gland
Supplementary Figure 5 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 5 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 6 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 6 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Table 1. A list of top 200 differentially expressed genes in xenografts from inject... more Supplementary Table 1. A list of top 200 differentially expressed genes in xenografts from injection of shMFNG MDA-MB231 cells vs. control MDA-MB231 cells
Supplementary Information. Including Supplementary Figure Legends, Supplementary Methods, and Sup... more Supplementary Information. Including Supplementary Figure Legends, Supplementary Methods, and Supplementary References.
Supplementary Figure 3 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 3 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
Supplementary Figure 4. Pharmacological inhibition of PI3Kγ has no effect on proliferation of MDA... more Supplementary Figure 4. Pharmacological inhibition of PI3Kγ has no effect on proliferation of MDA-MB231 cells, but shows an inhibitory effect on C0321 cells.
Supplementary Figure 8 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor F... more Supplementary Figure 8 from Cooperation between Pik3ca and p53 Mutations in Mouse Mammary Tumor Formation
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