bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from High Plasma Levels and Effective Lymphatic Uptake of Docetaxel in an Orally Available Nanotransporter Formulation
Authors: Nassar Taher , Attili-Qadri Suha , Harush-Frenkel Oshrat , Farber Shimon , Lecht Shimon , Lazarovici Philip , Benita Simon
Published: March 2023

Abstract
Docetaxel, an efficient chemotherapeutic drug, exhibits low and variable oral bioavailability due to the active efflux by P-glycoprotein (P-gp) and more so to CYP3A4 gut metabolism. Using a spray-drying technique, docetaxel was incorporated in PLGA [poly(lactic-co-glycolic acid)] nanocapsules (NC) which were embedded in entero-coated microparticles. An oral administration of the NC formulation elicited a higher absolute bioavailability than both a docetaxel solution (276%) and a free docetaxel NC formulation (400%) injected intravenously, a 5-mg/kg dose. The batches (B) I and II NC formulations elicited Cmax values that were 1,735% and 2,254%, respectively; higher than the Cmax value of the oral docetaxel solution combined with blank microparticles, a 10-mg/kg dose. No significant difference in AUC (area under curve) was observed between the batches. These unexpected results can be explained only if the pharmacokinetics of docetaxel had been modified. It was shown that NCs released from the microparticles penetrated the enterocytes, bypassing P-gp; apparently circumventing gut metabolism and accumulating within the lymphatic system from where both intact or biodegraded NCs and free docetaxel were progressively released into the circulation as plausibly supported by the fluorescent imaging results. Furthermore, the circulating docetaxel in plasma was unencapsulated and circulated either in free form or bound to albumin. Both free docetaxel NCs and microparticles exhibited in vitro efficacy on WRC 256 cells suggesting that the activity of docetaxel was not altered. This delivery concept has potential for clinical translation, perhaps allowing docetaxel chemotherapy to be switched from intravenous to oral delivery. Cancer Res; 71(8); 3018–28. ©2011 AACR.
Data from Stromal Estrogen Receptor-α Promotes Tumor Growth by Normalizing an Increased Angiogenesis
Authors: Péqueux Christel , Raymond-Letron Isabelle , Blacher Silvia , Boudou Frédéric , Adlanmerini Marine , Fouque Marie-José , Rochaix Philippe , Noël Agnès , Foidart Jean-Michel , Krust Andrée , Chambon Pierre , Brouchet Laurent , Arnal Jean-François , Lenfant Françoise
Published: March 2023

Abstract
Estrogens directly promote the growth of breast cancers that express the estrogen receptor α (ERα). However, the contribution of stromal expression of ERα in the tumor microenvironment to the protumoral effects of estrogen has never been explored. In this study, we evaluated the molecular and cellular mechanisms by which 17β-estradiol (E2) impacts the microenvironment and modulates tumor development of ERα-negative tumors. Using different mouse models of ER-negative cancer cells grafted subcutaneously into syngeneic ovariectomized immunocompetent mice, we found that E2 potentiates tumor growth, increases intratumoral vessel density, and modifies tumor vasculature into a more regularly organized structure, thereby improving vessel stabilization to prevent tumor hypoxia and necrosis. These E2-induced effects were completely abrogated in ERα-deficient mice, showing a critical role of host ERα. Notably, E2 did not accelerate tumor growth when ERα was deficient in Tie2-positive cells, even in mice grafted with wild-type bone marrow. These results were extended by clinical evidence of ERα-positive stromal cell labeling in the microenvironment of human breast cancers. Together, our findings therefore show that E2 promotes the growth of ERα-negative cancer cells through the activation of stromal ERα (extra-hematopoietic Tie-2 positive cells), which normalizes tumor angiogenesis and allows an adaptation of blood supply to tumors, thereby preventing hypoxia and necrosis. These findings significantly deepen mechanistic insights into the impact of E2 on tumor development with potential consequences for cancer treatment. Cancer Res; 72(12); 3010–9. ©2012 AACR.
Data from MYC Phosphorylation, Activation, and Tumorigenic Potential in Hepatocellular Carcinoma Are Regulated by HMG-CoA Reductase
Authors: Cao Zhongwei , Fan-Minogue Hua , Bellovin David I. , Yevtodiyenko Aleksey , Arzeno Julia , Yang Qiwei , Gambhir Sanjiv Sam , Felsher Dean W.
Published: March 2023

Abstract
MYC is a potential target for many cancers but is not amenable to existing pharmacologic approaches. Inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) by statins has shown potential efficacy against a number of cancers. Here, we show that inhibition of HMG-CoA reductase by atorvastatin (AT) blocks both MYC phosphorylation and activation, suppressing tumor initiation and growth in vivo in a transgenic model of MYC-induced hepatocellular carcinoma (HCC) as well as in human HCC-derived cell lines. To confirm specificity, we show that the antitumor effects of AT are blocked by cotreatment with the HMG-CoA reductase product mevalonate. Moreover, by using a novel molecular imaging sensor, we confirm that inhibition of HMG-CoA reductase blocks MYC phosphorylation in vivo. Importantly, the introduction of phosphorylation mutants of MYC at Ser62 or Thr58 into tumors blocks their sensitivity to inhibition of HMG-CoA reductase. Finally, we show that inhibition of HMG-CoA reductase suppresses MYC phosphorylation through Rac GTPase. Therefore, HMG-CoA reductase is a critical regulator of MYC phosphorylation, activation, and tumorigenic properties. The inhibition of HMG-CoA reductase may be a useful target for the treatment of MYC-associated HCC as well as other tumors. Cancer Res; 71(6); 2286–97. ©2011 AACR.
Data from Mucin Glycosylating Enzyme GALNT2 Regulates the Malignant Character of Hepatocellular Carcinoma by Modifying the EGF Receptor
Authors: Wu Yao-Ming , Liu Chiung-Hui , Hu Rey-Heng , Huang Miao-Juei , Lee Jian-Jr , Chen Chi-Hau , Huang John , Lai Hong-Shiee , Lee Po-Huang , Hsu Wen-Ming , Huang Hsiu-Chin , Huang Min-Chuan
Published: March 2023

Abstract
Extracellular glycosylation is a critical determinant of malignant character. Here, we report that N-acetylgalactosaminyltransferase 2 (GALNT2), the enzyme that mediates the initial step of mucin type-O glycosylation, is a critical mediator of malignant character in hepatocellular carcinoma (HCC) that acts by modifying the activity of the epidermal growth factor receptor (EGFR). GALNT2 mRNA and protein were downregulated frequently in HCC tumors where these events were associated with vascular invasion and recurrence. Restoring GALNT2 expression in HCC cells suppressed EGF-induced cell growth, migration, and invasion in vitro and in vivo. Mechanistic investigations revealed that the status of the O-glycans attached to the EGFR was altered by GALNT2, changing EGFR responses after EGF binding. Inhibiting EGFR activity with erlotinib decreased the malignant characters caused by siRNA-mediated knockdown of GALNT2 in HCC cells, establishing the critical role of EGFR in mediating the effects of GALNT2 expression. Taken together, our results suggest that GALNT2 dysregulation contributes to the malignant behavior of HCC cells, and they provide novel insights into the significance of O-glycosylation in EGFR activity and HCC pathogenesis. Cancer Res; 71(23); 7270–9. ©2011 AACR.
Data from Anti-IL-23 Monoclonal Antibody Synergizes in Combination with Targeted Therapies or IL-2 to Suppress Tumor Growth and Metastases
Authors: Teng Michele W.L. , von Scheidt Bianca , Duret Helene , Towne Jennifer E. , Smyth Mark J.
Published: March 2023

Abstract
Immunosuppressive barricades erected by tumors during the evolution of immune escape represent a major obstacle to many potentially effective cancer therapies and vaccines. We have shown that host interleukin (IL)-23 suppresses the innate immune response during carcinogenesis and metastasis, independently of effects on the proinflammatory cytokine IL-17A. Based on these findings, we envisioned that IL-23 neutralization might offer a promising strategy to modulate immunosuppression, particularly in combination with immunostimulatory agents. Here we show that by itself a neutralizing monoclonal antibody (mAb) to IL-23 suppressed early experimental lung metastases in the B16F10 mouse model of melanoma and also modestly inhibited the subcutaneous growth of primary tumors. These antitumor effects were respectively mediated by natural killer cells or CD8+ T cells. More notably, combinatorial treatments of anti-IL-23 mAb with IL-2 or anti-erbB2 mAb significantly inhibited subcutaneous growth of established mammary carcinomas and suppressed established experimental and spontaneous lung metastases. Overall, our results suggest the potential of anti-human IL-23 mAbs to improve the immunostimulatory effects of IL-2 and trastuzumab in the current management of some advanced human cancers. Cancer Res; 71(6); 2077–86. ©2011 AACR.
Data from MicroRNAs miR-199a-5p and -3p Target the Brm Subunit of SWI/SNF to Generate a Double-Negative Feedback Loop in a Variety of Human Cancers
Authors: Sakurai Kouhei , Furukawa Chihiro , Haraguchi Takeshi , Inada Ken-ichi , Shiogama Kazuya , Tagawa Takanobu , Fujita Shuji , Ueno Yoshihito , Ogata Aya , Ito Mai , Tsutsumi Yutaka , Iba Hideo
Published: March 2023

Abstract
The chromatin remodeling complex SWI/SNF is an important epigenetic regulator that includes one Brm or BRG1 molecule as catalytic subunit. Brm and BRG1 do not function identically, so this complex can regulate gene expression either positively or negatively, depending on the promoter to which it is recruited. Notably, Brm attenuation due to posttranscription suppression occurs often in human tumor cells, in which this event contributes to their oncogenic potential. Here, we report that the 3′-untranslated region of Brm mRNA has two sites that are efficiently targeted by the microRNAs miR-199a-5p and -3p, revealing a novel mechanism for modulation of Brm-type SWI/SNF activity. Computational mapping of the putative promoter region of miR-199a-2 (miPPR-199a-2) has defined it as the major contributing genetic locus for miR-199a-5p and-3p production in these tumor cell lines. We validated this predicted region by direct promoter analysis to confirm that Egr1 is a strong positive regulator of the miR-199a-2 gene. Importantly, we also showed that Egr1, miR-199a-5p, and miR-199a-3p are expressed at high levels in Brm-deficient tumor cell lines but only marginally in Brm-expressing tumor cells. Finally, we also obtained evidence that Brm negatively regulates Egr1. Together, our results reveal that miR-199a and Brm form a double-negative feedback loop through Egr1, leading to the generation of these two distinct cell types during carcinogenesis. This mechanism may offer a partial explanation for why miR-199a-5p and -3p have been reported to be either upregulated or downregulated in a variety of tumors. Cancer Res; 71(5); 1680–9. ©2010 AACR.
Data from MYB Is Essential for Mammary Tumorigenesis
Authors: Yu Miao Rebecca , Drabsch Yvette , Cross Ryan Stanley , Cheasley Dane , Carpinteri Sandra , Pereira Lloyd , Malaterre Jordane , Gonda Thomas J. , Anderson Robin L. , Ramsay Robert G.
Published: March 2023

Abstract
MYB oncogene upregulation is associated with estrogen receptor (ER)-positive breast cancer, but disease requirements for MYB function in vivo have not been explored. In this study, we provide evidence of a critical requirement for MYB functions in models of human and murine breast cancer. In human breast cancer, we found that MYB expression was critical for tumor cell growth both in vitro and in vivo in xenograft settings. In transgenic knockout mice, tissue-specific deletion of the murine MYB gene caused a transient defect in mammary gland development that was reflected in delayed ductal branching and defective apical bud formation. In mouse mammary tumor virus (MMTV)-NEU mice where tumors are initiated by activation of HER2, MYB deletion was sufficient to abolish tumor formation. In the more aggressive MMTV-PyMT model system, MYB deletion delayed tumorigenesis significantly. Together, the findings in these transgenic knockout models implied that MYB was critical during an early window in mammary development when it was essential for tumor initiation, even though MYB loss did not exert a lasting impact upon normal mammary function. Two important MYB-target genes that promote cell survival, BCL2 and GRP78/BIP, were each elevated compared with nontransformed mammary epithelial cells, thereby promoting survival as confirmed in colony formation assays in vitro. Taken together, our findings establish a role for MYB at the hub of ER- and HER2-dependent pathways in mammary carcinogenesis. Cancer Res; 71(22); 7029–37. ©2011 AACR.
Data from Cancer-Induced Immunosuppression: IL-18–Elicited Immunoablative NK Cells
Authors: Terme Magali , Ullrich Evelyn , Aymeric Laetitia , Meinhardt Kathrin , Coudert Jérôme D. , Desbois Mélanie , Ghiringhelli François , Viaud Sophie , Ryffel Bernard , Yagita Hideo , Chen Lieping , Mécheri Salaheddine , Kaplanski Gilles , Prévost-Blondel Armelle , Kato Masashi , Schultze Joachim L. , Tartour Eric , Kroemer Guido , Degli-Esposti Mariapia , Chaput Nathalie , Zitvogel Laurence
Published: March 2023

Abstract
During cancer development, a number of regulatory cell subsets and immunosuppressive cytokines subvert adaptive immune responses. Although it has been shown that tumor-derived interleukin (IL)-18 participates in the PD-1–dependent tumor progression in NK cell–controlled cancers, the mechanistic cues underlying this immunosuppression remain unknown. Here, we show that IL-18 converts a subset of Kit− (CD11b−) into Kit+ natural killer (NK) cells, which accumulate in all lymphoid organs of tumor bearers and mediate immunoablative functions. Kit+ NK cells overexpressed B7-H1/PD-L1, a ligand for PD-1. The adoptive transfer of Kit+ NK cells promoted tumor growth in two pulmonary metastases tumor models and significantly reduced the dendritic and NK cell pools residing in lymphoid organs in a B7-H1–dependent manner. Neutralization of IL-18 by RNA interference in tumors or systemically by IL-18–binding protein dramatically reduced the accumulation of Kit+CD11b− NK cells in tumor bearers. Together, our findings show that IL-18 produced by tumor cells elicits Kit+CD11b− NK cells endowed with B7-H1–dependent immunoablative functions in mice. Cancer Res; 72(11); 2757–67. ©2012 AACR.
Data from Raf Kinase Inhibitor Protein RKIP Enhances Signaling by Glycogen Synthase Kinase-3β
Authors: Al-Mulla Fahd , Bitar Milad S. , Al-Maghrebi May , Behbehani Abdulla I. , Al-Ali Waleed , Rath Oliver , Doyle Brendan , Tan Kit Yee , Pitt Andrew , Kolch Walter
Published: March 2023

Abstract
Raf kinase inhibitory protein (RKIP) is a physiologic inhibitor of c-RAF kinase and nuclear factor κB signaling that represses tumor invasion and metastasis. Glycogen synthase kinase-3β (GSK3β) suppresses tumor progression by downregulating multiple oncogenic pathways including Wnt signaling and cyclin D1 activation. Here, we show that RKIP binds GSK3 proteins and maintains GSK3β protein levels and its active form. Depletion of RKIP augments oxidative stress–mediated activation of the p38 mitogen activated protein kinase, which, in turn, inactivates GSK3β by phosphorylating it at the inhibitory T390 residue. This pathway de-represses GSK3β inhibition of oncogenic substrates causing stabilization of cyclin D, which induces cell-cycle progression and β-catenin, SNAIL, and SLUG, which promote epithelial to mesenchymal transition. RKIP levels in human colorectal cancer positively correlate with GSK3β expression. These findings reveal the RKIP/GSK3 axis as both a potential therapeutic target and a prognosis-based predictor of cancer progression. Cancer Res; 71(4); 1334–43. ©2011 AACR.
Data from Identification of Serum Biomarker Signatures Associated with Pancreatic Cancer
Authors: Wingren Christer , Sandström Anna , Segersvärd Ralf , Carlsson Anders , Andersson Roland , Löhr Matthias , Borrebaeck Carl A. K.
Published: March 2023

Abstract
Pancreatic cancer is an aggressive disease with poor prognosis, due, in part, to the lack of disease-specific biomarkers that could afford early and accurate diagnosis. With a recombinant antibody microarray platform, targeting mainly immunoregulatory proteins, we screened sera from 148 patients with pancreatic cancer, chronic pancreatitis, autoimmune pancreatitis (AIP), and healthy controls (N). Serum biomarker signatures were derived from training cohorts and the predictive power was evaluated using independent test cohorts. The results identified serum portraits distinguishing pancreatic cancer from N [receiver operating characteristics area under the curve (AUC) of 0.95], chronic pancreatitis (0.86), and AIP (0.99). Importantly, a 25-serum biomarker signature discriminating pancreatic cancer from the combined group of N, chronic pancreatitis, and AIP was determined. This signature exhibited a high diagnostic potential (AUC of 0.88). In summary, we present the first prevalidated, multiplexed serum biomarker signature for diagnosis of pancreatic cancer that may improve diagnosis and prevention in premalignant diseases and in screening of high-risk individuals. Cancer Res; 72(10); 2481–90. ©2012 AACR.
Data from Hippo/Mst1 Stimulates Transcription of the Proapoptotic Mediator NOXA in a FoxO1-Dependent Manner
Authors: Valis Karel , Prochazka Lubomir , Boura Evzen , Chladova Jaromira , Obsil Tomas , Rohlena Jakub , Truksa Jaroslav , Dong Lan-Feng , Ralph Stephen J. , Neuzil Jiri
Published: March 2023

Abstract
The proapoptotic protein Noxa, a member of the BH3-only Bcl-2 protein family, can effectively induce apoptosis in cancer cells, although the relevant regulatory pathways have been obscure. Previous studies of the cytotoxic effects of α-tocopheryl succinate (α-TOS) on cancer cells identified a mechanism whereby α-TOS caused apoptosis requiring the Noxa-Bak axis. In the present study, ab initio analysis revealed a conserved FoxO-binding site (DBE; DAF-16 binding element) in the NOXA promoter, and specific affinity of FoxO proteins to this DBE was confirmed by fluorescence anisotropy. FoxO1 and FoxO3a proteins accumulated in the nucleus of α-TOS–treated cells, and the drug-induced specific FoxO1 association with the NOXA promoter and its activation were validated by chromatin immunoprecipitation. Using siRNA knockdown, a specific role for the FoxO1 protein in activating NOXA transcription in cancer cells was identified. Furthermore, the proapoptotic kinase Hippo/Mst1 was found to be strongly activated by α-TOS, and inhibiting Hippo/Mst1 by specific siRNA prevented phosphorylation of FoxO1 and its nuclear translocation, thereby reducing levels of NOXA transcription and apoptosis in cancer cells exposed to α-TOS. Thus, we have demonstrated that anticancer drugs, exemplified by α-TOS, induce apoptosis by a mechanism involving the Hippo/Mst1-FoxO1-Noxa pathway. We propose that activation of this pathway provides a new paradigm for developing targeted cancer treatments. Cancer Res; 71(3); 946–54. ©2011 AACR.
Data from Cyclin D1 Inhibits Mitochondrial Activity in B Cells
Authors: Tchakarska Guergana , Roussel Mikel , Troussard Xavier , Sola Brigitte
Published: March 2023

Abstract
Cyclin D1 is a cell cycle regulatory protein that acts at the G1-S transition, following its binding to and activation by the cyclin-dependent kinases 4 or 6. Cyclin D1 is absent from the entire B-cell lineage but is present in a large percentage of 2 types of malignant B-cell hemopathy—mantle cell lymphoma and multiple myeloma— suggesting a major role of this protein in the malignancy process. We show here, in an experimental model of cyclin D1 fusion protein transduction in mature B cells, that, cyclin D1 inhibits total mitochondrial activity. Cyclin D1 is localized at the outer mitochondrial membrane, bound to a voltage-dependent anion channel through its central domain, and it competes with hexokinase 2 for binding to this channel. The bound cyclin D1 decreases the supply of ADP, ATP, and metabolites, thereby reducing energy production. This function of cyclin D1 was also reported by others in normal and transformed mammary epithelial cells, suggesting that it may be ubiquitous. Cancer Res; 71(5); 1690–9. ©2011 AACR.
Data from EMT and Stem Cell–Like Properties Associated with miR-205 and miR-200 Epigenetic Silencing Are Early Manifestations during Carcinogen-Induced Transformation of Human Lung Epithelial Cells
Authors: Tellez Carmen S. , Juri Daniel E. , Do Kieu , Bernauer Amanda M. , Thomas Cindy L. , Damiani Leah A. , Tessema Mathewos , Leng Shuguang , Belinsky Steven A.
Published: March 2023

Abstract
Epithelial-to-mesenchymal transition (EMT) is strongly associated with cancer progression, but its potential role during premalignant development has not been studied. Here, we show that a 4-week exposure of immortalized human bronchial epithelial cells (HBEC) to tobacco carcinogens can induce a persistent, irreversible, and multifaceted dedifferentiation program marked by EMT and the emergence of stem cell–like properties. EMT induction was epigenetically driven, initially by chromatin remodeling through H3K27me3 enrichment and later by ensuing DNA methylation to sustain silencing of tumor-suppressive microRNAs (miRNA), miR-200b, miR-200c, and miR-205, which were implicated in the dedifferentiation program in HBECs and also in primary lung tumors. Carcinogen-treated HBECs acquired stem cell–like features characterized by their ability to form spheroids with branching tubules and enrichment of the CD44high/CD24low, CD133, and ALDH1 stem cell–like markers. miRNA overexpression studies indicated that regulation of the EMT, stem-like, and transformed phenotypes in HBECs were distinct events. Our findings extend present concepts of how EMT participates in cancer pathophysiology by showing that EMT induction can participate in cancer initiation to promote the clonal expansion of premalignant lung epithelial cells. Cancer Res; 71(8); 3087–97. ©2011 AACR.
Data from Functional EGFR Germline Polymorphisms May Confer Risk for EGFR Somatic Mutations in Non–Small Cell Lung Cancer, with a Predominant Effect on Exon 19 Microdeletions
Authors: Liu Wanqing , He Lijun , Ramírez Jacqueline , Krishnaswamy Soundararajan , Kanteti Rajani , Wang Yi-Ching , Salgia Ravi , Ratain Mark J.
Published: March 2023

Abstract
Somatic mutations in the EGFR tyrosine kinase domain play a critical role in the development and treatment of non–small cell lung cancer (NSCLC). Strong genetic influence on susceptibility to these mutations has been suggested. To identify the genetic factors conferring risk for the EGFR tyrosine kinase mutations in NSCLC, a case–control study was conducted in 141 Taiwanese NSCLC patients by focusing on three functional polymorphisms in the EGFR gene [−216G/T, intron 1 (CA)n, and R497K]. Allelic imbalance of the EGFR −216G/T polymorphism was also tested in the heterozygous patients and in the NCI-60 cancer cell lines to further verify its function. We found that the frequencies of the alleles −216T and CA-19 are significantly higher in the patients with any mutation (P = 0.032 and 0.01, respectively), in particular in those with exon 19 microdeletions (P = 0.006 and 0.033, respectively), but not in the patients with L858R mutation. The −216T allele is favored to be amplified in both tumor DNA of lung cancer patients and cancer cell lines. We conclude that the local haplotype structures across the EGFR gene may favor the development of cellular malignancies and thus significantly confer risk to the occurrence of EGFR mutations in NSCLC, particularly the exon 19 microdeletions. Cancer Res; 71(7); 2423–7. ©2011 AACR.
Data from Cyclin D1 Activity Regulates Autophagy and Senescence in the Mammary Epithelium
Authors: Brown Nelson E. , Jeselsohn Rinath , Bihani Teeru , Hu Miaofen G. , Foltopoulou Parthena , Kuperwasser Charlotte , Hinds Philip W.
Published: March 2023

Abstract
Overexpression of cyclin D1 is believed to endow mammary epithelial cells (MEC) with a proliferative advantage by virtue of its contribution to pRB inactivation. Accordingly, abrogation of the kinase-dependent function of cyclin D1 is sufficient to render mice resistant to breast cancer initiated by ErbB2. Here, we report that mouse cyclin D1KE/KE MECs (deficient in cyclin D1 activity) upregulate an autophagy-like process but fail to implement ErbB2-induced senescence in vivo. In addition, immortalized cyclin D1KE/KE MECs retain high rates of autophagy and reduced ErbB2-mediated transformation in vitro. However, highlighting its dual role during tumorigenesis, downregulation of autophagy led to an increase in senescence in cyclin D1KE/KE MECs. Autophagy upregulation was also confirmed in human mammary epithelial cells (HMEC) subjected to genetic and pharmacologic inhibition of cyclin D1 activity and, similar to our murine system, simultaneous inhibition of Cdk4/6 and autophagy in HMECs enhanced the senescence response. Collectively, our findings suggest a previously unrecognized function of cyclin D1 in suppressing autophagy in the mammary epithelium. Cancer Res; 72(24); 6477–89. ©2012 AACR.
Data from Kaposi Sarcoma Herpesvirus Promotes Endothelial-to-Mesenchymal Transition through Notch-Dependent Signaling
Authors: Gasperini Paola , Espigol-Frigole Georgina , McCormick Peter J. , Salvucci Ombretta , Maric Dragan , Uldrick Thomas S. , Polizzotto Mark N. , Yarchoan Robert , Tosato Giovanna
Published: March 2023

Abstract
Endothelial-to-mesenchymal transition (EndMT) is now widely considered a pivotal contributor to cancer progression. In this study, we show that the Kaposi's sarcoma (KS)–associated herpesvirus (KSHV) is a sufficient cause of EndMT, potentially helping to explain the aggressiveness of KS that occurs commonly in AIDS patients. Upon KSHV infection, primary dermal microvascular endothelial cells lost expression of endothelial markers and acquired expression of mesenchymal markers, displaying new invasive and migratory properties along with increased survival. KSHV activated Notch-induced transcription factors Slug and ZEB1, and canonical Notch signaling was required for KSHV-induced EndMT. In contrast, KSHV did not utilize the TGFβ signaling pathway, which has also been linked to EndMT. Within KS lesions, KSHV-infected spindle cells displayed features compatible with KSHV-induced EndMT including a complex phenotype of endothelial and mesenchymal properties, Notch activity, and nuclear ZEB1 expression. Our results show that KSHV engages the EndMT program to increase the invasiveness and survival of infected endothelial cells, traits that likely contribute to viral persistence and malignant progression. One important implication of our findings is that therapeutic approaches to disrupt the Notch pathway may offer novel approaches for KS treatment. Cancer Res; 72(5); 1157–69. ©2012 AACR.
Data from Opposing Effects of Pigment Epithelium–Derived Factor on Breast Cancer Cell versus Neuronal Survival: Implication for Brain Metastasis and Metastasis-Induced Brain Damage
Authors: Fitzgerald Daniel P. , Subramanian Preeti , Deshpande Monika , Graves Christian , Gordon Ira , Qian Yongzhen , Snitkovsky Yeva , Liewehr David J. , Steinberg Seth M. , Paltán-Ortiz José D. , Herman Mary M. , Camphausen Kevin , Palmieri Diane , Becerra S. Patricia , Steeg Patricia S.
Published: March 2023

Abstract
Brain metastases are a significant cause of morbidity and mortality for patients with cancer, yet preventative and therapeutic options remain an unmet need. The cytokine pigment epithelium–derived factor (PEDF) is downregulated in resected human brain metastases of breast cancer compared with primary breast tumors, suggesting that restoring its expression might limit metastatic spread. Here, we show that outgrowth of large experimental brain metastases from human 231-BR or murine 4T1-BR breast cancer cells was suppressed by PEDF expression, as supported by in vitro analyses as well as direct intracranial implantation. Notably, the suppressive effects of PEDF were not only rapid but independent of the effects of this factor on angiogenesis. Paralleling its cytotoxic effects on breast cancer cells, PEDF also exerted a prosurvival effect on neurons that shielded the brain from tumor-induced damage, as indicated by a relative 3.5-fold reduction in the number of dying neurons adjacent to tumors expressing PEDF. Our findings establish PEDF as both a metastatic suppressor and a neuroprotectant in the brain, highlighting its role as a double agent in limiting brain metastasis and its local consequences. Cancer Res; 72(1); 144–53. ©2012 AACR.
Data from KEAP1-Dependent Synthetic Lethality Induced by AKT and TXNRD1 Inhibitors in Lung Cancer
Authors: Dai Bingbing , Yoo Suk-Young , Bartholomeusz Geoffrey , Graham Ryan A. , Majidi Mourad , Yan Shaoyu , Meng Jieru , Ji Lin , Coombes Kevin , Minna John D. , Fang Bingliang , Roth Jack A.
Published: March 2023

Abstract
Intrinsic resistance to agents targeting phosphoinositide 3-kinase (PI3K)/AKT pathway is one of the major challenges in cancer treatment with such agents. The objective of this study is to identify the genes or pathways that can be targeted to overcome the resistance of non–small cell lung carcinoma (NSCLC) to the AKT inhibitor MK2206, which is currently being evaluated in phase I and II clinical trials. Using a genome-wide siRNA library screening and biologic characterization, we identified that inhibition of thioredoxin reductase-1 (TXNRD1), one of the key antioxidant enzymes, with siRNAs or its inhibitor, auranofin, sensitized NSCLC cells to MK2206 treatment in vitro and in vivo. We found that simultaneous inhibition of TXNRD1 and AKT pathways induced robust reactive oxygen species production, which was involved in c-jun-NH2-kinase (JNK; MAPK8) activation and cell apoptosis. Furthermore, we found that the synthetic lethality interaction between the TXNRD1 and AKT pathways occurred through the KEAP1/NRF2 cellular antioxidant pathway. Finally, we found that synthetic lethality induced by TXNRD1 and AKT inhibitors relied on wild-type KEAP1 function. Our study indicates that targeting the interaction between AKT and TXNRD1 antioxidant pathways with MK2206 and auranofin, a U.S. Food and Drug Administration-approved drug, is a rational strategy to treat lung cancer and that KEAP1 mutation status may offer a predicative biomarker for such combination approaches. Cancer Res; 73(17); 5532–43. ©2013 AACR.
Data from Predictive Performance of Microarray Gene Signatures: Impact of Tumor Heterogeneity and Multiple Mechanisms of Drug Resistance
Authors: Ng Charlotte K.Y. , Weigelt Britta , A'Hern Roger , Bidard Francois-Clement , Lemetre Christophe , Swanton Charles , Shen Ronglai , Reis-Filho Jorge S.
Published: March 2023

Abstract
Gene signatures have failed to predict responses to breast cancer therapy in patients to date. In this study, we used bioinformatic methods to explore the hypothesis that the existence of multiple drug resistance mechanisms in different patients may limit the power of gene signatures to predict responses to therapy. In addition, we explored whether substratification of resistant cases could improve performance. Gene expression profiles from 1,550 breast cancers analyzed with the same microarray platform were retrieved from publicly available sources. Gene expression changes were introduced in cases defined as sensitive or resistant to a hypothetical therapy. In the resistant group, up to five different mechanisms of drug resistance causing distinct or overlapping gene expression changes were generated bioinformatically, and their impact on sensitivity, specificity, and predictive values of the signatures was investigated. We found that increasing the number of resistance mechanisms corresponding to different gene expression changes weakened the performance of the predictive signatures generated, even if the resistance-induced changes in gene expression were sufficiently strong and informative. Performance was also affected by cohort composition and the proportion of sensitive versus resistant cases or resistant cases that were mechanistically distinct. It was possible to improve response prediction by substratifying chemotherapy-resistant cases from actual datasets (non-bioinformatically perturbed datasets) and by using outliers to model multiple resistance mechanisms. Our work supports the hypothesis that the presence of multiple resistance mechanisms in a given therapy in patients limits the ability of gene signatures to make clinically useful predictions. Cancer Res; 74(11); 2946–61. ©2014 AACR.
Data from Neuromedin U: A Candidate Biomarker and Therapeutic Target to Predict and Overcome Resistance to HER-Tyrosine Kinase Inhibitors
Authors: Rani Sweta , Corcoran Claire , Shiels Liam , Germano Serena , Breslin Susan , Madden Stephen , McDermott Martina S. , Browne Brigid C. , O'Donovan Norma , Crown John , Gogarty Martina , Byrne Annette T. , O'Driscoll Lorraine
Published: March 2023

Abstract
Intrinsic and acquired resistance to HER-targeting drugs occurs in a significant proportion of HER2-overexpressing breast cancers. Thus, there remains a need to identify predictive biomarkers that could improve patient selection and circumvent these types of drug resistance. Here, we report the identification of neuromedin U (NmU) as an extracellular biomarker in cells resistant to HER-targeted drugs. NmU overexpression occurred in cells with acquired or innate resistance to lapatinib, trastuzumab, neratinib, and afatinib, all of which displayed a similar trend upon short-term exposure, suggesting NmU induction may be an early response. An analysis of 3,489 cases of breast cancer showed NmU to be associated with poor patient outcome, particularly those with HER2-overexpressing tumors independent of established prognostic indicators. Ectopic overexpression of NmU in drug-sensitive cells conferred resistance to all HER-targeting drugs, whereas RNAi-mediated attenuation sensitized cells exhibiting acquired or innate drug resistance. Mechanistic investigations suggested that NmU acted through HSP27 as partner protein to stabilize HER2 protein levels. We also obtained evidence of functional NmU receptors on HER2-overexpressing cells, with the addition of exogenous NmU eliciting an elevation in HER2 and EGFR expression along with drug resistance. Finally, we found that NmU seemed to function in cell motility, invasion, and anoikis resistance. In vivo studies revealed that NmU attenuation impaired tumor growth and metastasis. Taken together, our results defined NmU as a candidate drug response biomarker for HER2-overexpressing cancers and as a candidate therapeutic target to limit metastatic progression and improve the efficacy of HER-targeted drugs. Cancer Res; 74(14); 3821–33. ©2014 AACR.
Data from Impact of Tumor Progression on Cancer Incidence Curves
Authors: Luebeck E. Georg , Curtius Kit , Jeon Jihyoun , Hazelton William D.
Published: March 2023

Abstract
Cancer arises through a multistage process, but it is not fully clear how this process influences the age-specific incidence curve. Studies of colorectal and pancreatic cancer using the multistage clonal expansion (MSCE) model have identified two phases of the incidence curves. One phase is linear, beginning about age of 60 years, suggesting that at least two rare rate-limiting mutations occur before clonal expansion of premalignant cells. A second phase is exponential, seen in early-onset cancers occurring before the age of 60 years that are associated with premalignant clonal expansion. Here, we extend the MSCE model to include clonal expansion of malignant cells, an advance that permits study of the effects of tumor growth and extinction on the incidence of colorectal, gastric, pancreatic, and esophageal adenocarcinomas in the digestive tract. After adjusting the age-specific incidence for birth-cohort and calendar-year trends, we found that initiating mutations and premalignant cell kinetics can explain the primary features of the incidence curve. However, we also found that the incidence data of these cancers harbored information on the kinetics of malignant clonal expansion before clinical detection, including tumor growth rates and extinction probabilities on three characteristic time scales for tumor progression. In addition, the data harbored information on the mean sojourn times for premalignant clones until occurrence of either the first malignant cell or the first persistent (surviving) malignant clone. Finally, the data also harbored information on the mean sojourn time of persistent malignant clones to the time of diagnosis. In conclusion, cancer incidence curves can harbor significant information about hidden processes of tumor initiation, premalignant clonal expansion, and malignant transformation, and even some limited information on tumor growth before clinical detection. Cancer Res; 73(3); 1086–96. ©2012 AACR.
Data from Low PIP4K2B Expression in Human Breast Tumors Correlates with Reduced Patient Survival: A Role for PIP4K2B in the Regulation of E-Cadherin Expression
Authors: Keune Willem-Jan , Sims Andrew H. , Jones David R. , Bultsma Yvette , Lynch James T. , Jirström Karin , Landberg Goran , Divecha Nullin
Published: March 2023

Abstract
Phosphatidylinositol-5-phosphate (PtdIns5P) 4-kinase β (PIP4K2B) directly regulates the levels of two important phosphoinositide second messengers, PtdIns5P and phosphatidylinositol-(4,5)-bisphosphate [PtdIns(4,5)P2]. PIP4K2B has been linked to the regulation of gene transcription, to TP53 and AKT activation, and to the regulation of cellular reactive oxygen accumulation. However, its role in human tumor development and on patient survival is not known. Here, we have interrogated the expression of PIP4K2B in a cohort (489) of patients with breast tumor using immunohistochemical staining and by a meta-analysis of gene expression profiles from 2,999 breast tumors, both with associated clinical outcome data. Low PIP4K2B expression was associated with increased tumor size, high Nottingham histological grade, Ki67 expression, and distant metastasis, whereas high PIP4K2B expression strongly associated with ERBB2 expression. Kaplan–Meier curves showed that both high and low PIP4K2B expression correlated with poorer patient survival compared with intermediate expression. In normal (MCF10A) and tumor (MCF7) breast epithelial cell lines, mimicking low PIP4K2B expression, using short hairpin RNA interference-mediated knockdown, led to a decrease in the transcription and expression of the tumor suppressor protein E-cadherin (CDH1). In MCF10A cells, knockdown of PIP4K2B enhanced TGF-β–induced epithelial to mesenchymal transition (EMT), a process required during the development of metastasis. Analysis of gene expression datasets confirmed the association between low PIP4K2B and low CDH1expression. Decreased CDH1 expression and enhancement of TGF-β–induced EMT by reduced PIP4K2B expression might, in part, explain the association between low PIP4K2B expression and poor patient survival. Cancer Res; 73(23); 6913–25. ©2013 AACR.
Data from USP22 Regulates Oncogenic Signaling Pathways to Drive Lethal Cancer Progression
Authors: Schrecengost Randy S. , Dean Jeffry L. , Goodwin Jonathan F. , Schiewer Matthew J. , Urban Mark W. , Stanek Timothy J. , Sussman Robyn T. , Hicks Jessica L. , Birbe Ruth C. , Draganova-Tacheva Rossitza A. , Visakorpi Tapio , DeMarzo Angelo M. , McMahon Steven B. , Knudsen Karen E.
Published: March 2023

Abstract
Increasing evidence links deregulation of the ubiquitin-specific proteases 22 (USP22) deubitiquitylase to cancer development and progression in a select group of tumor types, but its specificity and underlying mechanisms of action are not well defined. Here we show that USP22 is a critical promoter of lethal tumor phenotypes that acts by modulating nuclear receptor and oncogenic signaling. In multiple xenograft models of human cancer, modeling of tumor-associated USP22 deregulation demonstrated that USP22 controls androgen receptor accumulation and signaling, and that it enhances expression of critical target genes coregulated by androgen receptor and MYC. USP22 not only reprogrammed androgen receptor function, but was sufficient to induce the transition to therapeutic resistance. Notably, in vivo depletion experiments revealed that USP22 is critical to maintain phenotypes associated with end-stage disease. This was a significant finding given clinical evidence that USP22 is highly deregulated in tumors, which have achieved therapeutic resistance. Taken together, our findings define USP22 as a critical effector of tumor progression, which drives lethal phenotypes, rationalizing this enzyme as an appealing therapeutic target to treat advanced disease. Cancer Res; 74(1); 272–86. ©2013 AACR.
Data from High-Throughput Tyrosine Kinase Activity Profiling Identifies FAK as a Candidate Therapeutic Target in Ewing Sarcoma
Authors: Crompton Brian D. , Carlton Anne L. , Thorner Aaron R. , Christie Amanda L. , Du Jinyan , Calicchio Monica L. , Rivera Miguel N. , Fleming Mark D. , Kohl Nancy E. , Kung Andrew L. , Stegmaier Kimberly
Published: March 2023

Abstract
Limited progress has been made in the treatment of advanced-stage pediatric solid tumors despite the accelerated pace of cancer discovery over the last decade. Tyrosine kinase inhibition is one tractable therapeutic modality for treating human malignancy. However, little is known about the kinases critical to the development or maintenance of many pediatric solid tumors such as Ewing sarcoma. Using a fluorescent, bead-based technology to profile activated tyrosine kinases, we identified focal adhesion kinase (FAK, PTK2) as a candidate target in Ewing sarcoma. FAK is a tyrosine kinase critical for cellular adhesion, growth, and survival. As such, it is a compelling target for cancer-based therapy. In this study, we have shown that FAK is highly phosphorylated in primary Ewing sarcoma tumor samples and that downregulation of FAK by short hairpin RNA and treatment with a FAK-selective kinase inhibitor, PF-562271, impaired growth and colony formation in Ewing sarcoma cell lines. Moreover, treatment of Ewing sarcoma cell lines with PF-562271 induced apoptosis and led to downregulation of AKT/mTOR and CAS activity. Finally, we showed that small-molecule inhibition of FAK attenuated Ewing sarcoma tumor growth in vivo. With FAK inhibitors currently in early-phase clinical trials for adult malignancies, these findings may bear immediate relevance to patients with Ewing sarcoma. Cancer Res; 73(9); 2873–83. ©2013 AACR.
Data from Compensatory Functions and Interdependency of the DNA-Binding Domain of BRCA2 with the BRCA1–PALB2–BRCA2 Complex
Authors: Al Abo Muthana , Dejsuphong Donniphat , Hirota Kouji , Yonetani Yasukazu , Yamazoe Mitsuyoshi , Kurumizaka Hitoshi , Takeda Shunichi
Published: March 2023

Abstract
BRCA1, BRCA2, and PALB2 are key players in cellular tolerance to chemotherapeutic agents, including camptothecin, cisplatin, and PARP inhibitor. The N-terminal segment of BRCA2 interacts with PALB2, thus contributing to the formation of the BRCA1–PALB2–BRCA2 complex. To understand the role played by BRCA2 in this complex, we deleted its N-terminal segment and generated BRCA2ΔN mutant cells. Although previous studies have suggested that BRCA1–PALB2 plays a role in the recruitment of BRCA2 to DNA-damage sites, BRCA2ΔN mutant cells displayed a considerably milder phenotype than did BRCA2−/− null-deficient cells. We hypothesized that the DNA-binding domain (DBD) of BRCA2 might compensate for a defect in BRCA2ΔN that prevented stable interaction with PALB2. To test this hypothesis, we disrupted the DBD of BRCA2 in wild-type and BRCA2ΔN cells. Remarkably, although the resulting BRCA2ΔDBD cells displayed a moderate phenotype, the BRCA2ΔN+ΔDBD cells displayed a very severe phenotype, as did the BRCA2−/− cells, suggesting that the N-terminal segment and the DBD play a substantially overlapping role in the functionality of BRCA2. We also showed that the formation of both the BRCA1–PALB2–BRCA2 complex and the DBD is required for efficient recruitment of BRCA2 to DNA-damage sites. Our study revealed the essential role played by both the BRCA1–PALB2–BRCA2 complex and the DBD in the functionality of BRCA2, as each can compensate for the other in the recruitment of BRCA2 to DNA-damage sites. This knowledge adds to our ability to accurately predict the efficacy of antimalignant therapies for patients carrying mutations in the BRCA2 gene. Cancer Res; 74(3); 797–807. ©2013 AACR.
Data from Identification of Immune Factors Regulating Antitumor Immunity Using Polymeric Vaccines with Multiple Adjuvants
Authors: Ali Omar A. , Verbeke Catia , Johnson Chris , Sands R. Warren , Lewin Sarah A. , White Des , Doherty Edward , Dranoff Glenn , Mooney David J.
Published: March 2023

Abstract
The innate cellular and molecular components required to mediate effective vaccination against weak tumor-associated antigens remain unclear. In this study, we used polymeric cancer vaccines incorporating different classes of adjuvants to induce tumor protection, to identify dendritic cell (DC) subsets and cytokines critical to this efficacy. Three-dimensional, porous polymer matrices loaded with tumor lysates and presenting distinct combinations of granulocyte macrophage colony-stimulating factor (GM-CSF) and various Toll-like receptor (TLR) agonists affected 70% to 90% prophylactic tumor protection in B16-F10 melanoma models. In aggressive, therapeutic B16 models, the vaccine systems incorporating GM-CSF in combination with P(I:C) or CpG-ODN induced the complete regression of solid tumors (≤40 mm2), resulting in 33% long-term survival. Regression analysis revealed that the numbers of vaccine-resident CD8(+) DCs, plasmacytoid DCs (pDC), along with local interleukin (IL)-12, and granulocyte colony-stimulating factor (G-CSF) concentrations correlated strongly to vaccine efficacy regardless of adjuvant type. Furthermore, vaccine studies in Batf3−/− mice revealed that CD8(+) DCs are required to affect tumor protection, as vaccines in these mice were deficient in cytotoxic T lymphocytes priming and IL-12 induction in comparison with wild-type. These studies broadly demonstrate that three-dimensional polymeric vaccines provide a potent platform for prophylactic and therapeutic protection, and can be used as a tool to identify critical components of a desired immune response. Specifically, these results suggest that CD8(+) DCs, pDCs, IL-12, and G-CSF play important roles in priming effective antitumor responses with these vaccines. Cancer Res; 74(6); 1670–81. ©2014 AACR.