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Results for “Cancer Biology”

Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

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At least 1,225 records · Page 68Linked to original sources

bioRxiv2019

Overexpression of long noncoding RNA GAS5 suppresses tumorigenesis and development of gastric cancer by sponging miR-106a-5p through the Akt/mToR pathway

Long non-coding RNAs (lncRNAs) have emerged as important regulators of human cancers. LncRNA GAS5 (GAS5) is identified tumor suppressor involved in several cancers. However, the roles of GAS5 and the mechanisms responsible for its functions in gastric cancer (GC) have not been well undocumented. Herein, the decreased GAS5 and increased miRNA-106a-5p levels were observed in GC and cell lines. GAS5 expression level was significantly inversely correlated with miRNA-106a-5p level in GC tissues. Moreover, luciferase reporter and qRT-PCR assays showed that GAS5 bound to miRNA-106a-5p and negatively regulated its expression in GC cells. Functional experiments showed that GAS5 overexpression suppressed GC cell proliferation, migration, and invasion capabilities and promoted apoptosis, while miRNA-106a-5p overexpression inversed the functional effects induced by GAS5 overexpression. In vivo, GAS5 overexpression inhibited tumor growth by negatively regulating miRNA-106a-5p expression. Mechanistic investigations revealed that GAS5 overexpression inactivating the Akt/mToR pathway by suppressing miRNA-106a-5p expression in vitro and in vivo. Taken together, our findings conclude the GAS5 overexpression suppresses tumorigenesis and development of gastric cancer by sponging miR-106a-5p through the Akt/mToR pathway.

cancer biology↗

bioRxiv2019

Mitotic gene bookmarking by RUNX1 contributes to stabilization of the normal mammary epithelial phenotype

RUNX1 has recently been shown to play an important role in determination of mammary epithelial cell identity. However, mechanisms by which loss of the RUNX1 transcription factor in mammary epithelial cells leads to epithelial-to-mesenchymal transition (EMT) are not known. Here, we report mitotic bookmarking of genes by RUNX1 as a potential mechanism to convey regulatory information through successive cell divisions for coordinate control of mammary cell proliferation, growth, and identity. Genome-wide RUNX1 occupancy profiles for asynchronous, mitotically enriched, and early G1 breast epithelial cells reveal RUNX1 is retained during the mitosis to G1 transition on protein coding and long non-coding RNA genes critical for mammary epithelial proliferation, growth, and phenotype maintenance. Disruption of RUNX1 DNA binding and association with mitotic chromosomes alters cell morphology, global protein synthesis, and phenotype-related gene expression. Together, these findings show for the first time that RUNX1 bookmarks a subset of epithelial-related genes during mitosis that remain occupied as cells enter the next cell cycle. Compromising RUNX1 DNA binding initiates EMT, an essential first step in the onset of breast cancer. SignificanceThis study elucidates mitotic gene bookmarking as a potential epigenetic mechanism that impacts breast epithelial cell growth and phenotype and has potential implications in breast cancer onset.

cancer biology↗

bioRxiv2019

Distinguishing Closely Related Pancreatic Cancer Subtypes In Vivo by 13C Glucose MRI without Hyperpolarization

Metabolic differences between patients and within the tumor itself can be an important determinant in cancer treatment outcome. However, methods for determining these differences non-invasively in vivo have been lacking. Using pancreatic ductal adenocarcinoma as a model, we demonstrate that tumor xenografts with a similar genetic background can be distinguished by their differing rates of metabolism, as detected by imaging of uniformly 13C labeled glucose tracers using a newly developed technique using tensor decomposition for noise suppression to bring the signal to a detectable level without hyperpolarization of the tracer. Using this method, cancer subtypes that appeared to exhibit similar metabolic profiles by other techniques that measured steady state metabolism can be distinguished.

cancer biology↗

bioRxiv2019

Modelling the transport of fluid through heterogeneous, whole tumours in silico

It is critically important to understand and predict fluid transport within both physiological and pathological tissues in order to develop effective treatment strategies. Recent advances in high-resolution optical imaging allow the acquisition of whole tumour vascular networks which can be used to parameterise computational models to predict the fluid dynamics at all length scales across the tissue. This enables hypothesis testing around the role of the tumour microenvironment in determining transport characteristics, which would otherwise be unavailable using traditional experiments.\n\nIn this study, we present a novel computational framework for the efficient simulation of vascular blood flow and interstitial fluid transport based on complete three-dimensional, whole tumour vasculature obtained using high-resolution optical imaging. This framework comprises a Poiseuille flow model which simulates vascular blood flow within the vessel network, coupled via point sources of flux to a porous medium model describing interstitial fluid transport. We develop a computational algorithm for prescription of network boundary conditions and validation of tissue-scale fluid transport against measured in vivo perfusion data acquired using biomedical imaging tools. We present simulations of the model on orthoptic murine glioma and human colorectal carcinoma xenograft data (GL261 and LS147T, respectively), and perform sensitivity analysis on key unknown parameters relating to the tissue microenvironment, to understand their impact in predicting vascular and interstitial flow. Finally, we simulate radially varying vascular normalisation in a LS147T tumour and hypothesise that uniform normalisation is required to lower tumour interstitial fluid pressure.\n\nOur computational framework permits predictions of whole tumour fluid dynamics which incorporate the inherent architectural heterogeneities appearing at the micron-scale, and outputs three-dimensional spatial maps detailing these flow properties from micro to macro length scales. This provides vital information on the tumour microenvironment which could enable the design and delivery of future anti-cancer therapies.\n\nAuthor summaryThe structure of tumours varies widely, with dense and chaotically-formed networks of blood vessels that differ between each individual tumour and even between different regions of the same tumour. This atypical environment can inhibit the delivery of anti-cancer therapies. Computational tools are urgently required which incorporate micron-scale tumour biomechanics to predict tissue-scale fluid dynamics, and consequently the efficacy of cancer therapies.\n\nWe have developed a computational framework which integrates the complex tumour vascular architecture to predict fluid transport across all lengths scales in whole tumours. This enables computationally efficient hypothesis testing of cancer therapies which manipulate the tumour microenvironment in order to improve drug delivery to tumours.

cancer biology↗

bioRxiv2019

Longitudinal single cell profiling of regulatory T cells identifies IL-33 as a driver of tumor immunosuppression

Regulatory T cells (Tregs) can impair anti-tumor immune responses and are associated with poor prognosis in multiple cancer types. Tregs in human tumors span diverse transcriptional states distinct from those of peripheral Tregs, but their contribution to tumor development remains unknown. Here, we used single cell RNA-Seq to longitudinally profile conventional CD4+ T cells (Tconv) and Tregs in a genetic mouse model of lung adenocarcinoma. Tissue-infiltrating and peripheral CD4+ T cells differed, highlighting divergent pathways of activation during tumorigenesis. Longitudinal shifts in Treg heterogeneity suggested increased terminal differentiation and stabilization of an effector phenotype over time. In particular, effector Tregs had enhanced expression of the interleukin 33 receptor ST2. Treg-specific deletion of ST2 reduced effector Tregs, increased infiltration of CD8+ T cells into tumors, and decreased tumor burden. Our study shows that ST2 plays a critical role in Treg-mediated immunosuppression in cancer, highlighting new potential paths for therapeutic intervention.

cancer biology↗

bioRxiv2019

Gene Panel Sequencing in a Chinese High-risk Breast Cancer Cohort

Currently, over 20 genes have been defined that can confer susceptibility for high-risk breast cancer. Although research has proved the utility of multiple-gene sequencing in the assessment of breast cancer risk, there is little data from China patients. Here, we use a multiple-gene sequencing panel to identify the variant spectrum in Chinese high-risk breast cancer subjects.\n\nA total of 829 Chinese high-risk breast cancer patients participated in the research. The coding regions of 115 hereditary cancer susceptibility genes were sequenced using a next generation sequencing platform. In total, 193 pathogenic variants were identified in 45 genes from 177 patients. The pathogenic variant carrier rate is 21.4%: with 10.5% patients carrying a BRCA1 or BRCA2 mutation only, 10.0% of patients carried non-BRCA gene mutations only, while 1.0% of patients carried both a BRCA1/2 and a non-BRCA gene mutation. Variants of uncertain significance (VUS) totaling 2632 were identified in 115 genes from 787 of 829 patients: 82.5% patients carried more than one VUS, and only 5.1% patients did not carry any VUS. Families carrying pathogenic variants were tracked and adenoma was founded in three of them. Our data provide a comprehensive analysis of potential susceptibility variations of high-risk for breast cancer in a Chinese population. This data will be useful for the comparison of the susceptibility variation spectrum between different populations and to discover potential pathogenic variants to improve the prevention and treatment of high-risk breast cancer.

cancer biology↗

bioRxiv2019

The antimicrobial peptide Defensin cooperates with Tumour Necrosis Factor to drive tumour cell death in Drosophila

Antimicrobial peptides (AMPs) are small cationic molecules best known as mediators of the innate defence against microbial infection. While in vitro and ex vivo evidence suggest AMPs capacity to kill cancer cells, in vivo demonstration of an anti-tumour role of endogenous AMPs is lacking. Using a Drosophila model of tumourigenesis, we demonstrate a role for the AMP Defensin in the control of tumour progression. Our results reveal that Tumour Necrosis Factor mediates exposure of phosphatidylserine (PS), which makes tumour cells selectively sensitive to the action of Defensin remotely secreted from tracheal and fat tissues. Defensin binds tumour cells in PS-enriched areas, provoking cell death and tumour regression. Altogether, our results provide the first in vivo demonstration for a role of an endogenous AMP as an anti-cancer agent, as well as a mechanism that explains tumour cell sensitivity to the action of AMPs.

cancer biology↗

bioRxiv2019

MIR2052HG regulates ERα levels and aromatase inhibitor resistance through LMTK3 by recruiting EGR1

Our previous GWAS using the MA.27 aromatase inhibitors (AIs) adjuvant trial identified SNPs in the lncRNA MIR2052HG associated with breast cancer free interval. Here we report that MIR2052HG depletion in breast cancer cells results in a decrease in LMTK3 expression and cell growth. Mechanistically, MIR2052HG interacts with EGR1 and facilitates its recruitment to the LMTK3 promoter. LMTK3 sustains ER levels by reducing PKC activity, resulting in increased ESR1 transcription mediated through AKT/FOXO3 and reduced ER degradation mediated by the PKC/MEK/ERK/RSK1 pathway. MIR2052HG regulated LMTK3 in a SNP- and aromatase inhibitor - dependent fashion: the variant SNP increased EGR1 binding to LMTK3 promoter in response to androstenedione, relative to wild-type genotype, a pattern that can be reversed by aromatase inhibitor treatment. Finally, LMTK3 overexpression abolished the effect of MIR2052HG on PKC activity and ER levels. These results reveal a direct role of MIR2052HG in LMTK3 regulation and raise the possibility of targeting MIR2052HG or LMTK3 in ER-positive breast cancer.

cancer biology↗

bioRxiv2019

Genetic Landscape of Electron Transport Chain Complex I Dependency in Acute Myeloid Leukemia

Inhibition of oxidative phosphorylation (OXPHOS) is a promising therapeutic strategy in Acute Myeloid Leukemia (AML), but patients respond heterogeneously. Through chemically interrogation of 200 sequenced specimens, we identified Mubritinib as a strong in vitro and in vivo anti-leukemic compound, acting through ubiquinone-dependent inhibition of Electron Transport Chain complex I (ETC1). ETC1 targeting showed selective toxicity against a subgroup of chemotherapy-resistant leukemias exhibiting OXPHOS hyperactivity, high expression of mitochondrial activity-related genes, and mutations affecting NPM1, FLT3 and DNMT3A. Altogether, our work thus identifies a novel ETC1 inhibitor with high clinical potential and reveals the landscape of OXPHOS dependency in AML.

cancer biology↗

bioRxiv2019

NRF2-dependent metabolic reprogramming is required for tumor recurrence following oncogene inhibition

Oncogenic signaling pathways both directly and indirectly regulate anabolic metabolism, and this is required for tumor growth. Targeted therapies that inhibit oncogenic signaling have dramatic impacts on cellular metabolism. However, it is not known whether the acquisition of resistance to these therapies is associated with - or driven by - alterations in cellular metabolism. To address this, we used a conditional mouse model of Her2-driven breast cancer to study metabolic adaptations following Her2 inhibition, during residual disease, and after tumor recurrence. We found that Her2 downregulation caused widespread changes in cellular metabolism, culminating in oxidative stress. Tumor cells adapted to this metabolic stress by upregulation of the antioxidant transcription factor, NRF2. Constitutive NRF2 expression persisted during residual disease and tumor recurrence, and NRF2 was both sufficient to promote tumor recurrence, and necessary for recurrent tumor growth. These results are supported by clinical data showing that the NRF2 transcriptional program is activated in recurrent breast tumors, and that NRF2 is associated with poor prognosis in patients with breast cancer. Mechanistically, NRF2 signaling in recurrent tumors induced metabolic reprogramming to re-establish redox homeostasis and upregulate de novo nucleotide synthesis. Finally, this NRF2-driven metabolic state rendered recurrent tumor cells sensitive to glutaminase inhibition, suggesting that NRF2-high recurrent tumors can be therapeutically targeted. Together, these data provide evidence that NRF2-driven metabolic reprogramming is required for breast cancer recurrence following oncogene inhibition.\n\nSignificanceAlthough tumor recurrence is the leading cause of mortality in breast cancer, the cellular properties that allow tumor cells to evade therapy and form recurrent tumors remain largely uncharacterized. Similarly, very little is known about how tumor metabolism changes following therapy, or whether alterations in cellular metabolism drive tumor recurrence. In this study, we identify the antioxidant transcription factor NRF2 as a critical positive regulator of breast cancer recurrence. We find that NRF2-dependent metabolic reprogramming is both sufficient and required to promote tumor recurrence. Additionally, we demonstrate that the NRF2-driven metabolic state renders recurrent tumors sensitive to glutaminase inhibitors, suggesting a novel therapeutic approach for the treatment of recurrent breast cancer.

cancer biology↗

bioRxiv2019

Frequency of mutations in 21 hereditary breast and ovarian cancer susceptibility genes among high-risk Chinese individuals

PurposeTo determine the prevalence and clinical prediction factors associated with deleterious mutations among 882 high-risk Chinese individuals who underwent multigene panel testing for hereditary breast and ovarian cancer (HBOC) risk assessment.\n\nExperimental DesignSubjects were selected from individuals referred for genetic testing using a 21-gene panel (Oseq-BRCA) between January 2015 and March 2018. The distribution and prevalence of deleterious mutations were analyzed for the full cohort as well as subtypes.\n\nResultsOverall, 176 deleterious mutations were observed in 19.50% (n = 172) individuals. Of these, 26 mutations are not reported in public databases and literatures. In the ovarian cancer only subgroup, 115 deleterious mutations were identified in 429 patients (48.6%). Patients with ovarian cancer with mutations were enriched for a family history of breast or ovarian cancers (p < 0.05). In the breast cancer only subgroup, 31 deleterious mutations were identified in 261 patients. Most mutations occurred in BRCA1 (8; 25.8%) and BRCA2 (11; 35.5%). An additional 12 deleterious mutations (38.7%) were found in 7 other susceptibility genes. An increased frequency of mutation rate (57.9%) was observed in the subgroup of subjects with histories of both breast and ovarian cancer.\n\nConclusions19.50% of individuals carried a deleterious mutation in HBOC susceptibility genes in our cohort. Subgroup of subjects with histories of both breast and ovarian cancer had the highest prevalence of mutations. Our results highlighted the genetic heterogeneity of HBOC and the efficiency of multigene panel in performing risk assessment.

cancer biology↗

bioRxiv2019

Control of MYC-dependent apoptotic threshold by a co-amplified ubiquitin E3 ligase UBR5

MYC protein expression has to be tightly controlled to allow for maximal cell proliferation without inducing apoptosis. Here we discover UBR5 as a novel MYC ubiquitin ligase and demonstrate how it functions as a molecular rheostat to prevent excess accumulation of MYC protein. UBR5 effects on MYC protein stability are independent on N-terminal FBW7 degron of MYC. Endogenous UBR5 inhibition induces MYC protein expression and activates MYC target genes. Moreover, UBR5 governs MYC-dependent phenotypes in vivo in Drosophila. In cancer cells, UBR5-mediated MYC protein suppression diminishes cell killing activity of cancer therapeutics. Further, we demonstrate that UBR5 dominates MYC protein expression at the single-cell level in human basal-type breast cancer tissue. Myc and Ubr5 are co-amplified in MYC-driven human cancer types, and UBR5 controls MYC-mediated apoptotic threshold in co-amplified basal type breast cancer cells. In summary, UBR5 is a novel MYC ubiquitin ligase and an endogenous rheostat for MYC protein expression in vivo. Clinically, expression of UBR5 may be important for protection of breast cancer cells from drug-induced, and MYC-dependent, apoptosis.

cancer biology↗

bioRxiv2019

Castration-resistant prostate cancer: Androgen receptor inactivation induces telomere DNA damage, and damage response inhibition leads to cell death

Telomere stability is important for cell viability, as cells with telomere DNA damage that is not repaired do not survive. We reported previously that androgen receptor (AR) antagonist induces telomere DNA damage in androgen-sensitive LNCaP prostate cancer cells; this triggers a DNA damage response (DDR) at telomeres that includes activation of ATM, and blocking ATM activation prevents telomere DNA repair and leads to cell death. Remarkably, AR antagonist induces telomere DNA damage and triggers ATM activation at telomeres also in 22Rv1 castration-resistant prostate cancer (CRPC) cells that are not growth inhibited by AR antagonist. Treatment with AR antagonist enzalutamide (ENZ) or ATM inhibitor (ATMi) by itself had no effect on growth in vitro or in vivo, but combined treatment with ENZ plus ATMi significantly inhibited cell survival in vitro and tumor growth in vivo. By inducing telomere DNA damage and activating a telomere DDR, an opportunity to inhibit DNA repair and promote cell death was created, even in CRPC cells. 22Rv1 cells express both full-length AR and AR splice variant AR-V7, but full-length AR was found to be the predominant form of AR associated with telomeres and required for telomere stability. Although 22Rv1 growth of untreated 22Rv1 cells appears to be driven by AR-V7, it is, ironically, expression of full-length AR that makes them sensitive to growth inhibition by combined treatment with ENZ plus ATMi. Notably, this combined treatment approach to induce telomere DNA damage and inhibit the DDR was effective in inducing cell death also in other CRPC cell lines (LNCaP/AR and C4-2B). Thus, the use of ENZ in combination with a DDR inhibitor, such as ATMi, may be effective in prolonging disease-free survival of patients with AR-positive metastatic CRPC, even those that co-express AR splice variant.

cancer biology↗

bioRxiv2019

Neuroendocrine negative SCLC is mostly RB1 WT and may be sensitive to CDK4/6 inhibition

Small cell lung cancer (SCLC) is an aggressive form of lung cancer with limited therapeutic options, a very high mortality rate and is characterized, in most cases, by neuroendocrine features. A small but important subset of SCLC has intact RB1. However, other characteristics of this subset are not well-defined. To comprehensively assess the underlying genomics of SCLC cell lines with functional RB1, we examined 48 SCLC cell lines from the Cancer Cell Line Encyclopedia (CCLE) collection. Out of these 48 SCLC cell lines, 8 were found to be RB1 WT. We found that RB1 WT SCLC lines are enriched for loss of neuroendocrine lineage markers with CDKN2A inactivation, or CCND1 amplification. Six RB1 WT SCLC cell lines were included in NCI SCLC drug sensitivity screen and two of them were sensitive to CDK4/6 inhibition.

cancer biology↗

bioRxiv2019

RBM10 variants and RBM5 involve in alternative splicing of RBM10v1 pre-mRNA: RBM10v1 includes its own exon 4, but RBM10v2 and RBM5 skip it.

RNA binding motif (RBM) proteins, RBM10v1, RBM10v2 and RBM5 have quite similar molecular structures with a high degree of the conserved domains. Alternative splicing of RBM10 pre-mRNA produces the two mRNA variants, RBM10v1 (exon 4-included) and RBM10v2 (exon 4-skipped). RBM10v1 has a 77 amino acids-domain coded by its exon 4, but RBM10v2 lacks it. I explored the alternative splicing of the RBM10 pre-mRNA by the above three RBMs in COS-7, lung adenocarcinoma A549 and differentiated mouse cardiomyocytes H9c2 cells. Firstly, COS-7 and A549 cells express both RBM10v1 and RBM10v2 mRNA variants in contrast to H9c2 cells which express RBM10v2 variant alone. Transfection experiments of RBM10v1, RBM10v2 or RBM5 were performed to examine the alternative splicing of RBM10v1 pre-mRNA in COS-7, A549 and H9c2 cells. The result showed that RBM10v1 includes, by itself, its own exon 4 of the pre-mRNA in contrast to RBM10v2 and RBM5 which exclude the exon 4. The inclusion of the exon 4 seems to be repressed in differentiated H9c2 cells.

cancer biology↗

bioRxiv2019

NEK10 tyrosine phosphorylates p53 and controls its transcriptional activity

In response to genotoxic stress, multiple kinase signalling cascades are activated, many of them directed towards the tumour suppressor p53 which coordinates the DNA damage response (DDR). Defects in DDR pathways lead to an accumulation of mutations that can promote tumorigenesis. Emerging evidence implicates multiple members of the NimA-related kinase (NEK) family (NEK1, NEK10 and NEK11) in the DDR. Here, we describe a function for NEK10 in the regulation of p53 transcriptional activity through tyrosine phosphorylation. NEK10 loss increases cellular proliferation through modulation of the p53-dependent transcriptional output, by directly phosphorylating p53 on Y327, revealing NEK10s unexpected substrate specificity. A p53 mutant at this site (Y327F) acts as a hypomorph, causing an attenuated p53-mediated transcriptional response. Consistently, NEK10-deficient cells display heightened sensitivity to DNA damaging agents and low NEK10 expression is an independent predictor of a favorable response to radiation treatment in WT TP53 breast cancer patients.

cancer biology↗

bioRxiv2019

Low-dose IFN-γ induces tumor cell stemness in tumor microenvironment of non-small cell lung cancer

Interferon-{gamma} (IFN-{gamma}) is conventionally recognized as an inflammatory cytokine that play a central role in antitumor immunity. Clinically, although has been used clinically to treat a variety of malignancies, low-level IFN-{gamma} in the tumor microenvironment (TME) increases the risk of tumor metastasis during immunotherapy. Accumulating evidence has suggested that IFN-{gamma} can induce cancer progression. The mechanisms underlying the controversial role of IFN-{gamma} regulating tumor development remain unclear. Herein, we firstly revealed a dose-dependent effect of IFN-{gamma} in inducing tumor stemness to accelerate cancer progression in patients with a variety of cancer types. Mechanically, low-level IFN-{gamma} endowed cancer stem-like properties via the intercellular adhesion molecule-1 (ICAM1)-PI3K-Akt-Notch1 axis, whereas high-level IFN-{gamma} activated the JAK1-STAT1-caspase pathway to induce apoptosis in non-small cell lung cancer (NSCLC). Inhibition of ICAM1 abrogated the stem-like properties of NSCLC cells induced by the low dose of IFN-{gamma} both in vitro and in vivo. Our study first defines the role of low-level IFN-{gamma} in conferring tumor stemness and clearly elucidate the distinct signaling pathways activated by IFN-{gamma} in a dose-dependent manner, providing new insights into cancer treatment, particularly patients with low-level IFN-{gamma} expression in the TME.

cancer biology↗

bioRxiv2019

From the clinic to the bench and back again in one dog year: identifying new treatments for sarcoma using a cross-species personalized medicine pipeline

Cancer drug discovery is an inefficient process, with more than 90% of newly-discovered therapies failing to gain regulatory approval. Patient-derived models of cancer offer a promising new approach to identifying personalized treatments; however, for rare cancers, such as sarcomas, access to patient samples can be extremely limited, which precludes development of patient-derived models. To address the limited access to patient samples, we have turned to pet dogs with naturally-occurring sarcomas. Although sarcomas make up less than 1% of all cancers in humans, sarcomas represent at least 15% of all cancers in dogs. Dogs with naturally-occurring sarcomas also have intact immune systems, an accelerated pace of cancer progression, and share the same environment as humans, making them ideal models that bridge key gaps between mouse models and human sarcomas.\n\nHere, we develop a framework for a personalized medicine pipeline that integrates drug screening, validation, and genomics to identify new therapies. We tested this paradigm through the study of a pet dog, Teddy, who presented with six synchronous leiomyosarcomas. By integrating patient-derived cancer models, in vitro drug screens, and in vivo validation we identified proteasome inhibitors as a potential therapy for Teddy. After showing an initial response to the proteasome inhibitor, bortezomib, Teddy developed rapid resistance, and tumor growth resumed. Whole exome sequencing revealed substantial genetic heterogeneity across Teddys multiple recurrent tumors and metastases, suggesting that intra-patient heterogeneity was responsible for the heterogeneous clinical response. Ubiquitin proteomics coupled with exome sequencing revealed multiple candidate driver mutations in proteins related to the proteasome pathway. Together, our results demonstrate how the comparative study of canine sarcomas can offer rapid insights into the process of developing personalized medicine approaches that can lead to new treatments for sarcomas in both humans and canines.

cancer biology↗