Medicine and Health Sciences Commons^™

Cancer Cell Population Growth Kinetics At Low Densities Deviate From The Exponential Growth Model And Suggest An Allee Effect., Kaitlyn E Johnson, Grant Howard, William Mo, Michael K Strasser, Ernesto A B F Lima, Sui Huang, Amy Brock

Articles, Abstracts, and Reports

Most models of cancer cell population expansion assume exponential growth kinetics at low cell densities, with deviations to account for observed slowing of growth rate only at higher densities due to limited resources such as space and nutrients. However, recent preclinical and clinical observations of tumor initiation or recurrence indicate the presence of tumor growth kinetics in which growth rates scale positively with cell numbers. These observations are analogous to the cooperative behavior of species in an ecosystem described by the ecological principle of the Allee effect. In preclinical and clinical models, however, tumor growth data are limited by the …

Commonly Integrated Epigenetic Modifications Of Differentially Expressed Genes Lead To Adaptive Resistance In Cancer., Abdullah Al Emran, Diego M Marzese, Dinoop R Menon, Heinz Hammerlindl, Farzana Ahmed, Erika Richtig, Pascal Duijf, Dave Hoon, Helmut Schaider

Articles, Abstracts, and Reports

Aim: To investigate the integrated epigenetic regulation of acquired drug resistance in cancer. Materials & methods: Our gene expression data of five induced drug-tolerant cell models, one resistant cell line and one publicly available drug-resistant dataset were integrated to identify common differentially expressed genes and pathways. ChIP-seq and DNA methylation by HM450K beadchip were used to study the epigenetic profile of differential expressed genes. Results & conclusion: Integrated transcriptomic analysis identified a common 'viral mimicry' related gene signature in induced drug-tolerant cells and the resistant state. Analysis of the epigenetic regulation revealed a common set of down-regulated genes, which are …

Rare But Recurrent Ros1 Fusions Resulting From Chromosome 6q22 Microdeletions Are Targetable Oncogenes In Glioma., Monika A Davare, Jacob J Henderson, Anupriya Agarwal, Jacob P Wagner, Sudarshan R Iyer, Nameeta Shah, Randy Woltjer, Romel Somwar, Stephen W Gilheeney, Ana Decarvalo, Tom Mikkelson, Erwin G Van Meir, Marc Ladanyi, Brian J Druker

Articles, Abstracts, and Reports

PURPOSE: Gliomas, a genetically heterogeneous group of primary central nervous system tumors, continue to pose a significant clinical challenge. Discovery of chromosomal rearrangements involving kinase genes has enabled precision therapy, and improved outcomes in several malignancies.

EXPERIMENTAL DESIGN: Positing that similar benefit could be accomplished for patients with brain cancer, we evaluated The Cancer Genome Atlas (TCGA) glioblastoma dataset. Functional validation of the oncogenic potential and inhibitory sensitivity of discovered ROS1 fusions was performed using three independent cell-based model systems, and an

RESULTS:

CONCLUSIONS: Our findings highlight that CNS tumors should be specifically interrogated for these rare intrachromosomal 6q22 microdeletion …

Potent Immune Modulation By Medi6383, An Engineered Human Ox40 Ligand Igg4p Fc Fusion Protein., Michael D Oberst, Catherine Augé, Chad Morris, Stacy Kentner, Kathy Mulgrew, Kelly Mcglinchey, James Hair, Shino Hanabuchi, Qun Du, Melissa Damschroder, Hui Feng, Steven Eck, Nicholas Buss, Lolke De Haan, Andrew J Pierce, Haesun Park, Andrew Sylwester, Michael K Axthelm, Louis Picker, Nicholas P Morris, Andrew D Weinberg, Scott A Hammond

Articles, Abstracts, and Reports

Ligation of OX40 (CD134, TNFRSF4) on activated T cells by its natural ligand (OX40L, CD252, TNFSF4) enhances cellular survival, proliferation, and effector functions such as cytokine release and cellular cytotoxicity. We engineered a recombinant human OX40L IgG4P Fc fusion protein termed MEDI6383 that assembles into a hexameric structure and exerts potent agonist activity following engagement of OX40. MEDI6383 displayed solution-phase agonist activity that was enhanced when the fusion protein was clustered by Fc gamma receptors (FcγRs) on the surface of adjacent cells. The resulting costimulation of OX40 on T cells induced NFκB promoter activity in OX40-expressing T cells and induced …

Nadph Oxidase 5 (Nox5)-Induced Reactive Oxygen Signaling Modulates Normoxic Hif-1Α And P27, Smitha Antony, Guojian Jiang, Yongzhong Wu, Jennifer L Meitzler, Hala R Makhlouf, Diana C Haines, Donna Butcher, Dave S B Hoon, Jiuping Ji, Yiping Zhang, Agnes Juhasz, Jiamo Lu, Han Liu, Iris Dahan, Mariam Konate, Krishnendu K Roy, James H Doroshow

Articles, Abstracts, and Reports

NADPH oxidase 5 (NOX5) generated reactive oxygen species (ROS) have been implicated in signaling cascades that regulate cancer cell proliferation. To evaluate and validate NOX5 expression in human tumors, we screened a broad range of tissue microarrays (TMAs), and report substantial overexpression of NOX5 in malignant melanoma and cancers of the prostate, breast, and ovary. In human UACC-257 melanoma cells that possesses high levels of functional endogenous NOX5, overexpression of NOX5 resulted in enhanced cell growth, increased numbers of BrdU positive cells, and increased γ-H2AX levels. Additionally, NOX5-overexpressing (stable and inducible) UACC-257 cells demonstrated increased normoxic HIF-1α expression and decreased …

Smarcb1 Is Required For Widespread Baf Complex-Mediated Activation Of Enhancers And Bivalent Promoters., Robert T Nakayama, John L Pulice, Alfredo M Valencia, Matthew J Mcbride, Zachary M Mckenzie, Mark A Gillespie, Wai Lim Ku, Mingxiang Teng, Kairong Cui, Robert T Williams, Seth H Cassel, He Qing, Christian J Widmer, George D Demetri, Rafael A Irizarry, Keji Zhao, Jeffrey A Ranish, Cigall Kadoch

Articles, Abstracts, and Reports

Perturbations to mammalian SWI/SNF (mSWI/SNF or BAF) complexes contribute to more than 20% of human cancers, with driving roles first identified in malignant rhabdoid tumor, an aggressive pediatric cancer characterized by biallelic inactivation of the core BAF complex subunit SMARCB1 (BAF47). However, the mechanism by which this alteration contributes to tumorigenesis remains poorly understood. We find that BAF47 loss destabilizes BAF complexes on chromatin, absent significant changes in complex assembly or integrity. Rescue of BAF47 in BAF47-deficient sarcoma cell lines results in increased genome-wide BAF complex occupancy, facilitating widespread enhancer activation and opposition of Polycomb-mediated repression at bivalent promoters. We …

Epigenetic Regulation Of Kpc1 Ubiquitin Ligase Affects The Nf-Κb Pathway In Melanoma., Yuuki Iida, Aaron Ciechanover, Diego M Marzese, Keisuke Hata, Matias Bustos, Shigeshi Ono, Jinhua Wang, Matthew P Salomon, Kevin Tran, Stella Lam, Sandy Hsu, Nellie Nelson, Yelena Kravtsova-Ivantsiv, Gordon B Mills, Michael A Davies, Dave S B Hoon

Articles, Abstracts, and Reports

Purpose: Abnormal activation of the NF-κB pathway induces a more aggressive phenotype of cutaneous melanoma. Understanding the mechanisms involved in melanoma NF-κB activation may identify novel targets for this pathway. KPC1, an E3 ubiquitin ligase, is a regulator of the NF-κB pathway. The objective of this study was to investigate the mechanisms regulating KPC1 expression and its clinical impact in melanoma.Experimental Design: The clinical impact of KPC1 expression and its epigenetic regulation were assessed in large cohorts of clinically well-annotated melanoma tissues (tissue microarrays; n = 137, JWCI cohort; n = 40) and The Cancer Genome Atlas database (TCGA …

A Tnf-Jnk-Axl-Erk Signaling Axis Mediates Primary Resistance To Egfr Inhibition In Glioblastoma., Gao Guo, Ke Gong, Sonia Ali, Neha Ali, Shahzad Shallwani, Kimmo J Hatanpaa, Edward Pan, Bruce Mickey, Sandeep Burma, David H Wang, Santosh Kesari, Jann N Sarkaria, Dawen Zhao, Amyn A Habib

Articles, Abstracts, and Reports

Aberrant epidermal growth factor receptor (EGFR) signaling is widespread in cancer, making the EGFR an important target for therapy. EGFR gene amplification and mutation are common in glioblastoma (GBM), but EGFR inhibition has not been effective in treating this tumor. Here we propose that primary resistance to EGFR inhibition in glioma cells results from a rapid compensatory response to EGFR inhibition that mediates cell survival. We show that in glioma cells expressing either EGFR wild type or the mutant EGFRvIII, EGFR inhibition triggers a rapid adaptive response driven by increased tumor necrosis factor (TNF) secretion, which leads to activation in …

The Rhoj-Bad Signaling Network: An Achilles' Heel For Braf Mutant Melanomas., Rolando Ruiz, Sohail Jahid, Melissa Harris, Diego M Marzese, Francisco Espitia, Priya Vasudeva, Chi-Fen Chen, Sebastien De Feraudy, Jie Wu, Daniel L Gillen, Tatiana B Krasieva, Bruce J Tromberg, William J Pavan, Dave S B Hoon, Anand K Ganesan

Articles, Abstracts, and Reports

Genes and pathways that allow cells to cope with oncogene-induced stress represent selective cancer therapeutic targets that remain largely undiscovered. In this study, we identify a RhoJ signaling pathway that is a selective therapeutic target for BRAF mutant cells. RhoJ deletion in BRAF mutant melanocytes modulates the expression of the pro-apoptotic protein BAD as well as genes involved in cellular metabolism, impairing nevus formation, cellular transformation, and metastasis. Short-term treatment of nascent melanoma tumors with PAK inhibitors that block RhoJ signaling halts the growth of BRAF mutant melanoma tumors in vivo and induces apoptosis in melanoma cells in vitro via …

Modulation Of Bax And Mtor For Cancer Therapeutics., Rui Li, Chunyong Ding, Jun Zhang, Maohua Xie, Dongkyoo Park, Ye Ding, Guo Chen, Guojing Zhang, Melissa Gilbert-Ross, Wei Zhou, Adam I Marcus, Shi-Yong Sun, Zhuo G Chen, Gabriel L Sica, Suresh S Ramalingam, Andrew T Magis, Haian Fu, Fadlo R Khuri, Walter J Curran, Taofeek K Owonikoko, Dong M Shin, Jia Zhou, Xingming Deng

Articles, Abstracts, and Reports

A rationale exists for pharmacologic manipulation of the serine (S)184 phosphorylation site of the proapoptotic Bcl2 family member Bax as an anticancer strategy. Here, we report the refinement of the Bax agonist SMBA1 to generate CYD-2-11, which has characteristics of a suitable clinical lead compound. CYD-2-11 targeted the structural pocket proximal to S184 in the C-terminal region of Bax, directly activating its proapoptotic activity by inducing a conformational change enabling formation of Bax homooligomers in mitochondrial membranes. In murine models of small-cell and non-small cell lung cancers, including patient-derived xenograft and the genetically engineered mutant KRAS-driven lung cancer models, CYD-2-11 …

Ccr4 Is A Determinant Of Melanoma Brain Metastasis., Anat Klein, Orit Sagi-Assif, Tsipi Meshel, Alona Telerman, Sivan Izraely, Shlomit Ben-Menachem, Jagadeesh Bayry, Diego M Marzese, Shuichi Ohe, Dave S B Hoon, Neta Erez, Isaac P Witz

Articles, Abstracts, and Reports

We previously identified the chemokine receptor CCR4 as part of the molecular signature of melanoma brain metastasis. The aim of this study was to determine the functional significance of CCR4 in melanoma brain metastasis. We show that CCR4 is more highly expressed by brain metastasizing melanoma cells than by local cutaneous cells from the same melanoma. Moreover, we found that the expression of CCR4 is significantly higher in paired clinical specimens of melanoma metastases than in samples of primary tumors from the same patients. Notably, the expression of the CCR4 ligands, Ccl22 and Ccl17 is upregulated at the earliest stages …

Astrocytes Promote Progression Of Breast Cancer Metastases To The Brain Via A Kiss1-Mediated Autophagy., Natalya Kaverina, Anton V Borovjagin, Zaira Kadagidze, Anatoly Baryshnikov, Maria Baryshnikova, Dmitry Malin, Dhimankrishhna Ghosh, Nameeta Shah, Danny R Welch, Patrik Gabikian, Apollon Karseladze, Charles Cobbs, Ilya V Ulasov

Articles, Abstracts, and Reports

Formation of metastases, also known as cancer dissemination, is an important stage of breast cancer (BrCa) development. KISS1 expression is associated with inhibition of metastases development. Recently we have demonstrated that BrCa metastases to the brain exhibit low levels of KISS1 expression at both mRNA and protein levels. By using multicolor immunofluorescence and coculture techniques here we show that normal adult astrocytes in the brain are capable of promoting metastatic transformation of circulating breast cancer cells localized to the brain through secretion of chemokine CXCL12. The latter was found in this study to downregulate KISS1 expression at the post-transcriptional level …

Foxc1 Is Associated With Estrogen Receptor Alpha And Affects Sensitivity Of Tamoxifen Treatment In Breast Cancer., Jinhua Wang, Yali Xu, Li Li, Lin Wang, Ru Yao, Qiang Sun, Guanhua Du

Articles, Abstracts, and Reports

FOXC1 is a member of Forkhead box transcription factors that participates in embryonic development and tumorigenesis. Our previous study demonstrated that FOXC1 was highly expressed in triple-negative breast cancer. However, it remains unclear what is the relation between FOXC1 and ERα and if FOXC1 regulates expression of ERα. To explore relation between FOXC1 and ERα and discover regulation of ERα expression by FOXC1 in breast cancer, we analyzed data assembled in the Oncomine and TCGA, and found that there was significantly higher FOXC1 expression in estrogen receptor-negative breast cancer than that in estrogen receptor-positive breast cancer. Overexpression of FOXC1 reduced …

Logic Models To Predict Continuous Outputs Based On Binary Inputs With An Application To Personalized Cancer Therapy., Theo A Knijnenburg, Gunnar W Klau, Francesco Iorio, Mathew J Garnett, Ultan Mcdermott, Ilya Shmulevich, Lodewyk F A Wessels

Articles, Abstracts, and Reports

Mining large datasets using machine learning approaches often leads to models that are hard to interpret and not amenable to the generation of hypotheses that can be experimentally tested. We present 'Logic Optimization for Binary Input to Continuous Output' (LOBICO), a computational approach that infers small and easily interpretable logic models of binary input features that explain a continuous output variable. Applying LOBICO to a large cancer cell line panel, we find that logic combinations of multiple mutations are more predictive of drug response than single gene predictors. Importantly, we show that the use of the continuous information leads to …