bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from MDC1 Cleavage by Caspase-3: A Novel Mechanism for Inactivating the DNA Damage Response during Apoptosis
Authors: Solier Stéphanie , Pommier Yves
Published: March 2024

Abstract
Recently, we identified the “apoptotic ring,” containing phosphorylated histone H2AX (γ-H2AX), as an early chromatin modification during apoptosis. Because γ-H2AX initiates the DNA damage response (DDR), we tested whether the apoptotic H2AX response leads to the full recruitment of the DDR factors that normally coordinate DNA repair and cell-cycle checkpoints. We show that the apoptotic H2AX response does not recruit the DDR factors because MDC1 (mediator of DNA damage checkpoint protein 1), which normally binds to γ-H2AX in response to DNA damage and amplifies the DDR, is cleaved by caspase-3. This cleavage separates the BRCT and FHA domains of MDC1 and constitutes a novel mechanism for the inactivation of DNA repair in apoptotic cells. Also, we show that downregulation of MDC1 increases the apoptotic response to TRAIL. Together, these results implicate MDC1 in the cellular apoptotic response. Cancer Res; 71(3); 906–13. ©2010 AACR.
Data from The Novel Metastasis Promoter Merm1/Wbscr22 Enhances Tumor Cell Survival in the Vasculature by Suppressing Zac1/p53-Dependent Apoptosis
Authors: Nakazawa Youya , Arai Hiroyuki , Fujita Naoya
Published: March 2024

Abstract
Understanding metastasis is integral to curative cancer treatments. Using a mouse genetic screening model, we identified Merm1/Wbscr22 as a novel metastasis promoter that includes a methyltransferase fold in its structure. Merm1 showed high levels of expression in invasive breast cancer. Ectopic expression of Merm1 in nonmetastatic cells enhanced metastasis formation without affecting cell growth and motility. The intact methyltransferase fold of Merm1 was required for metastasis formation. Interestingly, Merm1 expression promoted cell survival after entrapment in the lung microvasculature. Consistent with these results, knockdown of endogenous Merm1 in tumor cells reduced lung retention and metastasis formation. On the basis of comparative transcriptome analysis, Merm1 expression was negatively correlated with the expression of tumor suppressor Zac1. We confirmed that Merm1 suppressed Zac1 expression with histone H3 methylation at Lys9 in the Zac1 promoter region. Zac1 can induce apoptosis through its ability to transcriptionally coactivate p53, which regulates apoptosis in the vasculature and is often downregulated in metastasis. We found that Zac1 knockdown reduced the p53-dependent apoptosis that was enhanced by Merm1 knockdown, thereby increasing lung retention of metastatic cells. Our findings show that Merm1 enhances cancer cell survival in the vasculature by suppressing Zac1/p53-dependent apoptosis, thereby enhancing metastasis. Cancer Res; 71(3); 1146–55. ©2010 AACR.
Data from CAMTA1, a 1p36 Tumor Suppressor Candidate, Inhibits Growth and Activates Differentiation Programs in Neuroblastoma Cells
Authors: Henrich Kai-Oliver , Bauer Tobias , Schulte Johannes , Ehemann Volker , Deubzer Hedwig , Gogolin Sina , Muth Daniel , Fischer Matthias , Benner Axel , König Rainer , Schwab Manfred , Westermann Frank
Published: March 2024

Abstract
A distal portion of human chromosome 1p is often deleted in neuroblastomas and other cancers and it is generally assumed that this region harbors one or more tumor suppressor genes. In neuroblastoma, a 261 kb region at 1p36.3 that encompasses the smallest region of consistent deletion pinpoints the locus for calmodulin binding transcription activator 1 (CAMTA1). Low CAMTA1 expression is an independent predictor of poor outcome in multivariate survival analysis, but its potential functionality in neuroblastoma has not been explored. In this study, we used inducible cell models to analyze the impact of CAMTA1 on neuroblastoma biology. In neuroblastoma cells that expressed little endogenous CAMTA1, its ectopic expression slowed cell proliferation, increasing the relative proportion of cells in G1/G0 phases of the cell cycle, inhibited anchorage-independent colony formation, and suppressed the growth of tumor xenografts. CAMTA1 also induced neurite-like processes and markers of neuronal differentiation in neuroblastoma cells. Further, retinoic acid and other differentiation- inducing stimuli upregulated CAMTA1 expression in neuroblastoma cells. Transciptome analysis revealed 683 genes regulated on CAMTA1 induction and gene ontology analysis identified genes consistent with CAMTA1-induced phenotypes, with a significant enrichment for genes involved in neuronal function and differentiation. Our findings define properties of CAMTA1 in growth suppression and neuronal differentiation that support its assignment as a 1p36 tumor suppressor gene in neuroblastoma. Cancer Res; 71(8); 3142–51. ©2011 AACR.
Data from Phosphorylation of Carbonic Anhydrase IX Controls Its Ability to Mediate Extracellular Acidification in Hypoxic Tumors
Authors: Ditte Peter , Dequiedt Franck , Svastova Eliska , Hulikova Alzbeta , Ohradanova-Repic Anna , Zatovicova Miriam , Csaderova Lucia , Kopacek Juraj , Supuran Claudiu T. , Pastorekova Silvia , Pastorek Jaromir
Published: March 2024

Abstract
In the hypoxic regions of a tumor, carbonic anhydrase IX (CA IX) is an important transmembrane component of the pH regulatory machinery that participates in bicarbonate transport. Because tumor pH has implications for growth, invasion, and therapy, determining the basis for the contributions of CA IX to the hypoxic tumor microenvironment could lead to new fundamental and practical insights. Here, we report that Thr443 phosphorylation at the intracellular domain of CA IX by protein kinase A (PKA) is critical for its activation in hypoxic cells, with the fullest activity of CA IX also requiring dephosphorylation of Ser448. PKA is activated by cAMP, which is elevated by hypoxia, and we found that attenuating PKA in cells disrupted CA IX-mediated extracellular acidification. Moreover, following hypoxia induction, CA IX colocalized with the sodium-bicarbonate cotransporter and other PKA substrates in the leading edge membranes of migrating tumor cells, in support of the concept that bicarbonate metabolism is spatially regulated at cell surface sites with high local ion transport and pH control. Using chimeric CA IX proteins containing heterologous catalytic domains derived from related CA enzymes, we showed that CA IX activity was modulated chiefly by the intracellular domain where Thr443 is located. Our findings indicate that CA IX is a pivotal mediator of the hypoxia-cAMP–PKA axis, which regulates pH in the hypoxic tumor microenvironment. Cancer Res; 71(24); 7558–67. ©2011 AACR.
Data from PDK1 Attenuation Fails to Prevent Tumor Formation in PTEN-Deficient Transgenic Mouse Models
Authors: Ellwood-Yen Katharine , Keilhack Heike , Kunii Kaiko , Dolinski Brian , Connor Yamicia , Hu Kun , Nagashima Kumiko , O'Hare Erin , Erkul Yusuf , Di Bacco Alessandra , Gargano Diana , Shomer Nirah H. , Angagaw Minilik , Leccese Erica , Andrade Paula , Hurd Melissa , Shin Myung K. , Vogt Thomas F. , Northrup Alan , Bobkova Ekaterina V. , Kasibhatla Shailaja , Bronson Roderick T. , Scott Martin L. , Draetta Giulio , Richon Victoria , Kohl Nancy , Blume-Jensen Peter , Andersen Jannik N. , Kraus Manfred
Published: March 2024

Abstract
PDK1 activates AKT suggesting that PDK1 inhibition might suppress tumor development. However, while PDK1 has been investigated intensively as an oncology target, selective inhibitors suitable for in vivo studies have remained elusive. In this study we present the results of in vivo PDK1 inhibition through a universally applicable RNAi approach for functional drug target validation in oncogenic pathway contexts. This approach, which relies on doxycycline-inducible shRNA expression from the Rosa26 locus, is ideal for functional studies of genes like PDK1 where constitutive mouse models lead to strong developmental phenotypes or embryonic lethality. We achieved more than 90% PDK1 knockdown in vivo, a level sufficient to impact physiological functions resulting in hyperinsulinemia and hyperglycemia. This phenotype was reversible on PDK1 reexpression. Unexpectedly, long-term PDK1 knockdown revealed a lack of potent antitumor efficacy in 3 different mouse models of PTEN-deficient cancer. Thus, despite efficient PDK1 knockdown, inhibition of the PI3K pathway was marginal suggesting that PDK1 was not a rate limiting factor. Ex vivo analysis of pharmacological inhibitors revealed that AKT and mTOR inhibitors undergoing clinical development are more effective than PDK1 inhibitors at blocking activated PI3K pathway signaling. Taken together our findings weaken the widely held expectation that PDK1 represents an appealing oncology target. Cancer Res; 71(8); 3052–65. ©2011 AACR.
Data from Demethylation of RB Regulator MYPT1 by Histone Demethylase LSD1 Promotes Cell Cycle Progression in Cancer Cells
Authors: Cho Hyun-Soo , Suzuki Takehiro , Dohmae Naoshi , Hayami Shinya , Unoki Motoko , Yoshimatsu Masanori , Toyokawa Gouji , Takawa Masashi , Chen Taiping , Kurash Julia K. , Field Helen I. , Ponder Bruce A.J. , Nakamura Yusuke , Hamamoto Ryuji
Published: March 2024

Abstract
Histone demethylase LSD1 (also known as KDM1 and AOF2) is active in various cancer cells, but its biological significance in human carcinogenesis is unexplored. In this study, we explored hypothesized interactions between LSD1 and MYPT1, a known regulator of RB1 phosphorylation. We found that MYPT1 was methylated in vitro and in vivo by histone lysine methyltransferase SETD7 and demethylated by LSD1, identifying Lys 442 of MYPT1 as a target for methylation/demethylation by these enzymes. LSD1 silencing increased MYPT1 protein levels, decreasing the steady state level of phosphorylated RB1 (Ser 807/811) and reducing E2F activity. MYPT1 methylation status influenced the affinity of MYPT1 for the ubiquitin-proteasome pathway of protein turnover. MYPT1 was unstable in murine cells deficient in SETD7, supporting the concept that MYPT1 protein stability is physiologically regulated by methylation status. LSD1 overexpression could activate RB1 phosphorylation by inducing a destabilization of MYPT1 protein. Taken together, our results comprise a novel cell cycle regulatory mechanism mediated by methylation/demethylation dynamics, and they reveal the significance of LSD1 overexpression in human carcinogenesis. Cancer Res; 71(3); 655–60. ©2010 AACR.
Data from Functional Cooperation of RKTG with p53 in Tumorigenesis and Epithelial–Mesenchymal Transition
Authors: Jiang Yuhui , Xie Xiaoduo , Li Zhigang , Wang Zheng , Zhang Yixuan , Ling Zhiqiang , Pan Yi , Wang Zhenzhen , Chen Yan
Published: March 2024

Abstract
Raf kinase trapping to Golgi (RKTG) is a potential tumor suppressor gene due to its negative roles in regulating Ras/Raf/MEK/ERK (extracellular signal–regulated kinase) pathway and GPCR (G protein–coupled receptor) Gβγ subunit signaling. Interestingly, RKTG-deficient mice are free of tumors, although they are prone to form skin cancer on carcinogen administration. On the other hand, p53 is a well-characterized tumor suppressor gene and p53 heterozygous mice develop sarcoma and other tumors starting from 12 months of age. In RKTG-null mouse embryonic fibroblasts, lypophosphatidic acid (LPA), but not EGF (epidermal growth factor), could stimulate hyperphosphorylation of AKT and GSK3β, accompanied by increases in phosphorylation of p53 at Ser15 and accumulation of p53, as well as its target genes p21 and p16. Spontaneous skin cancer–like tumors were detected in about 25% of RKTG nullizygous and p53 heterozygous mice within 7 months of age. Hyperplasia and epithelial–mesenchymal transition (EMT) were observed in the tumor-overlying epidermis, in which LOH of p53 occurred and EMT features emerged. In p53-mutated A431 epithelial carcinoma cells, knockdown of RKTG led to enhancement of LPA-stimulated AKT and GSK3β phosphorylation, together with increased accumulation of β-catenin and appearance of EMT features that were antagonized by p53 overexpression. In HepG2 epithelial cells, LPA-stimulated AKT phosphorylation and EMT features reached maximum when both RKTG and p53 were simultaneously silenced. In summary, these results not only indicate that RKTG has an in vivo tumor suppressor function to cooperate with p53 in tumorigenesis but also suggest that p53 has an EMT checkpoint function and the loss of this function can combine with loss of RKTG to drive EMT and tumor progression. Cancer Res; 71(8); 2959–68. ©2011 AACR.
Data from A Multicellular Basis for the Origination of Blast Crisis in Chronic Myeloid Leukemia
Authors: Sachs Rainer K. , Johnsson Kerstin , Hahnfeldt Philip , Luo Janet , Chen Allen , Hlatky Lynn
Published: March 2024

Abstract
Chronic myeloid leukemia (CML) is characterized by a specific chromosome translocation, and its pathobiology is considered comparatively well understood. Thus, quantitative analysis of CML and its progression to blast crisis may help elucidate general mechanisms of carcinogenesis and cancer progression. Hitherto, it has been widely postulated that CML blast crisis originates mainly via cell-autonomous mechanisms such as secondary mutations or genomic instability. However, recent results suggest that carcinogenic transformation may be an inherently multicellular event, in departure from the classic unicellular paradigm. We investigate this possibility in the case of blast crisis origination in CML. A quantitative, mechanistic cell population dynamics model was employed. This model used recent data on imatinib-treated CML; it also used earlier clinical data, not previously incorporated into current mathematical CML/imatinib models. With the pre-imatinib data, which include results on many more blast crises, we obtained evidence that the driving mechanism for blast crisis origination is a cooperation between specific cell types. Assuming leukemic–normal interactions resulted in a statistically significant improvement over assuming either cell-autonomous mechanisms or interactions between leukemic cells. This conclusion was robust with regard to changes in the model's adjustable parameters. Application of the results to patients treated with imatinib suggests that imatinib may act not only on malignant blast precursors, but also, to a limited degree, on the malignant blasts themselves. Cancer Res; 71(8); 2838–47. ©2011 AACR.
Data from Pim Kinase Inhibitors Sensitize Prostate Cancer Cells to Apoptosis Triggered by Bcl-2 Family Inhibitor ABT-737
Authors: Song Jin H. , Kraft Andrew S.
Published: March 2024

Abstract
Pim serine/threonine kinases contribute to prostate tumorigenesis and therapeutic resistance, yet Pim kinase inhibitors seem to have only limited effects on prostate cancer cell survival. Because overexpression of Bcl-2 family members are implicated in chemotherapeutic resistance in prostate cancer, we investigated the cooperative effects of Pim kinase inhibition with ABT-737, a small molecule antagonist of Bcl-2 family members. Strikingly, the addition of ABT-737 to Pim inhibitors triggered a robust apoptosis of prostate cancer cells in vitro and in vivo. Pim inhibitors decreased levels of the Bcl-2 family member Mcl-1, both by blocking 5′-cap dependent translation and decreasing protein half life. In addition, Pim inhibition transcriptionally increased levels of the BH3 protein Noxa by activating the unfolded protein response (UPR), lead to eIF-2α phosphorylation and increased expression of CHOP. Increased levels of Noxa also inactivated the remaining levels of Mcl-1 protein activity. Notably, these specific protein changes were essential to the apoptotic process because ABT-737 did not inhibit Mcl-1 protein activity and Mcl-1 overexpression blocked the apoptotic activity of ABT-737. Our results therefore suggest that this combination treatment could be developed as a potential therapy for human prostate cancer where overexpression of Pim kinases and antiapoptotic Bcl-2 family members drives tumor cell resistance to current anticancer therapies. Cancer Res; 72(1); 294–303. ©2011 AACR.
Data from Antiangiogenic and Antimetastatic Activity of JAK Inhibitor AZD1480
Authors: Xin Hong , Herrmann Andreas , Reckamp Karen , Zhang Wang , Pal Sumanta , Hedvat Michael , Zhang Chunyan , Liang Wei , Scuto Anna , Weng Shaobu , Morosini Deborah , Cao Zhu A. , Zinda Michael , Figlin Robert , Huszar Dennis , Jove Richard , Yu Hua
Published: March 2024

Abstract
STAT3 has important functions in both tumor cells and the tumor microenvironment to facilitate cancer progression. The STAT regulatory kinase Janus-activated kinase (JAK) has been strongly implicated in promoting oncogenesis of various solid tumors, including the use of JAK kinase inhibitors such as AZD1480. However, direct evidence that JAK drives STAT3 function and cancer pathogenesis at the level of the tumor microenvironment is yet to be established clearly. In this study, we show that AZD1480 inhibits STAT3 in tumor-associated myeloid cells, reducing their number and inhibiting tumor metastasis. Myeloid cell–mediated angiogenesis was also diminished by AZD1480, with additional direct inhibition of endothelial cell function in vitro and in vivo. AZD1480 blocked lung infiltration of myeloid cells and formation of pulmonary metastases in both mouse syngeneic experimental and spontaneous metastatic models. Furthermore, AZD1480 reduced angiogenesis and metastasis in a human xenograft tumor model. Although the effects of AZD1480 on the tumor microenvironment were important for the observed antiangiogenic activity, constitutive activation of STAT3 in tumor cells themselves could block these antiangiogenic effects, showing the complexity of the JAK/STAT signaling network in tumor progression. Together, our results indicated that AZD1480 can effectively inhibit tumor angiogenesis and metastasis mediated by STAT3 in stromal cells as well as tumor cells. Cancer Res; 71(21); 6601–10. ©2011 AACR.
Data from Histone Lysine Methyltransferase SETD8 Promotes Carcinogenesis by Deregulating PCNA Expression
Authors: Takawa Masashi , Cho Hyun-Soo , Hayami Shinya , Toyokawa Gouji , Kogure Masaharu , Yamane Yuka , Iwai Yukiko , Maejima Kazuhiro , Ueda Koji , Masuda Akiko , Dohmae Naoshi , Field Helen I. , Tsunoda Tatsuhiko , Kobayashi Takaaki , Akasu Takayuki , Sugiyama Masanori , Ohnuma Shin-ichi , Atomi Yutaka , Ponder Bruce A.J. , Nakamura Yusuke , Hamamoto Ryuji
Published: March 2024

Abstract
Although the physiologic significance of lysine methylation of histones is well known, whether lysine methylation plays a role in the regulation of nonhistone proteins has not yet been examined. The histone lysine methyltransferase SETD8 is overexpressed in various types of cancer and seems to play a crucial role in S-phase progression. Here, we show that SETD8 regulates the function of proliferating cell nuclear antigen (PCNA) protein through lysine methylation. We found that SETD8 methylated PCNA on lysine 248, and either depletion of SETD8 or substitution of lysine 248 destabilized PCNA expression. Mechanistically, lysine methylation significantly enhanced the interaction between PCNA and the flap endonuclease FEN1. Loss of PCNA methylation retarded the maturation of Okazaki fragments, slowed DNA replication, and induced DNA damage, and cells expressing a methylation-inactive PCNA mutant were more susceptible to DNA damage. An increase of methylated PCNA was found in cancer cells, and the expression levels of SETD8 and PCNA were correlated in cancer tissue samples. Together, our findings reveal a function for lysine methylation on a nonhistone protein and suggest that aberrant lysine methylation of PCNA may play a role in human carcinogenesis. Cancer Res; 72(13); 3217–27. ©2012 AACR.
Data from COX-2 Blockade Suppresses Gliomagenesis by Inhibiting Myeloid-Derived Suppressor Cells
Authors: Fujita Mitsugu , Kohanbash Gary , Fellows-Mayle Wendy , Hamilton Ronald L. , Komohara Yoshihiro , Decker Stacy A. , Ohlfest John R. , Okada Hideho
Published: March 2024

Abstract
Epidemiologic studies have highlighted associations between the regular use of nonsteroidal anti-inflammatory drugs (NSAID) and reduced glioma risks in humans. Most NSAIDs function as COX-2 inhibitors that prevent production of prostaglandin E2 (PGE2). Because PGE2 induces expansion of myeloid-derived suppressor cells (MDSC), we hypothesized that COX-2 blockade would suppress gliomagenesis by inhibiting MDSC development and accumulation in the tumor microenvironment (TME). In mouse models of glioma, treatment with the COX-2 inhibitors acetylsalicylic acid (ASA) or celecoxib inhibited systemic PGE2 production and delayed glioma development. ASA treatment also reduced the MDSC-attracting chemokine CCL2 (C-C motif ligand 2) in the TME along with numbers of CD11b+Ly6GhiLy6Clo granulocytic MDSCs in both the bone marrow and the TME. In support of this evidence that COX-2 blockade blocked systemic development of MDSCs and their CCL2-mediated accumulation in the TME, there were defects in these processes in glioma-bearing Cox2-deficient and Ccl2-deficient mice. Conversely, these mice or ASA-treated wild-type mice displayed enhanced expression of CXCL10 (C-X-C motif chemokine 10) and infiltration of cytotoxic T lymphocytes (CTL) in the TME, consistent with a relief of MDSC-mediated immunosuppression. Antibody-mediated depletion of MDSCs delayed glioma growth in association with an increase in CXCL10 and CTLs in the TME, underscoring a critical role for MDSCs in glioma development. Finally, Cxcl10-deficient mice exhibited reduced CTL infiltration of tumors, establishing that CXCL10 limited this pathway of immunosuppression. Taken together, our findings show that the COX-2 pathway promotes gliomagenesis by directly supporting systemic development of MDSCs and their accumulation in the TME, where they limit CTL infiltration. Cancer Res; 71(7); 2664–74. ©2011 AACR.
Data from Epidermal Growth Factor Receptor Variant III Contributes to Cancer Stem Cell Phenotypes in Invasive Breast Carcinoma
Authors: Del Vecchio Catherine A. , Jensen Kristin C. , Nitta Ryan T. , Shain A. Hunter , Giacomini Craig P. , Wong Albert J.
Published: March 2024

Abstract
EGFRvIII is a tumor-specific variant of the epidermal growth factor receptor (EGFR). Although EGFRvIII is most commonly found in glioblastoma, its expression in other tumor types remains controversial. In this study, we investigated EGFRvIII expression and amplification in primary breast carcinoma. Our analyses confirmed the presence of EGFRvIII, but in the absence of amplification or rearrangement of the EGFR locus. Nested reverse transcriptase PCR and flow cytometry were used to detect a higher percentage of positive cases. EGFRvIII-positive cells showed increased expression of genes associated with self-renewal and epithelial–mesenchymal transition along with a higher percentage of stem-like cells. EGFRvIII also increased in vitro sphere formation and in vivo tumor formation. Mechanistically, EGFRvIII mediated its effects through the Wnt/β-catenin pathway, leading to increased β-catenin target gene expression. Inhibition of this pathway reversed the observed effects on cancer stem cell (CSC) phenotypes. Together, our findings show that EGFRvIII is expressed in primary breast tumors and contributes to CSC phenotypes in breast cancer cell lines through the Wnt pathway. These data suggest a novel function for EGFRvIII in breast tumorigenesis. Cancer Res; 72(10); 2657–71. ©2012 AACR.
Data from Cancer Immunotherapy Using a Bispecific NK Receptor Fusion Protein that Engages both T Cells and Tumor Cells
Authors: Zhang Tong , Sentman Charles L.
Published: March 2024

Abstract
T-cell immunotherapy is a promising strategy to treat cancer, but its efficacy, complexity, and costs may pose challenges. In this study, we report the results of an investigation of a new approach to selectively activate a T-cell attack against tumor cells. The immunotherapeutic approach we developed utilizes a bifunctional fusion protein that binds tumor cells through NK (natural killer)–activating receptor NKG2D and that recruits and stimulates T cells through an anti-CD3 single-chain variable fragment (scFv-NKG2D). In vitro, this scFv-NKG2D fusion protein engaged both T cells and tumor cells, stimulating T cells to produce IFN-γ, and cytotoxicity against NKG2D ligand–positive tumor cells. In vivo, expression of scFv-NKG2D by NKG2D ligand–positive tumor cells reduced tumor burden and, in some cases, led to tumor-free survival. Administration of scFv-NKG2D in vivo also promoted survival in a murine lymphoma model. Tumor-free mice were resistant to rechallenge with cognate tumor cells, suggesting that a host-specific immunologic memory response had been generated. Host adaptive immunity including γδ T cells was required for scFv-NKG2D–mediated therapeutic efficacy. ScFv-NKG2D also inhibited the growth of NKG2D ligand–negative B16F10 tumors, reduced the percentage of myeloid-derived suppressor cells and regulatory T cells, and increased the infiltration of T cells, suggesting that scFv-NKG2D may target these immune suppressive cells. Together, these results establish scFv-NKG2D as a promising biological fusion protein to induce effective antitumor immunity. Cancer Res; 71(6); 2066–76. ©2011 AACR.
Data from Cooperative Phosphorylation of FADD by Aur-A and Plk1 in Response to Taxol Triggers Both Apoptotic and Necrotic Cell Death
Authors: Jang Moon-Sun , Lee Su-Jin , Kang Nam Sook , Kim Eunhee
Published: March 2024

Abstract
Administration of the antimitotic chemotherapeutic taxol is known to cause accumulation of the mitotic kinase Aurora-A (Aur-A). Here, we report that Aur-A phosphorylates S203 of the Fas associated with death domain protein (FADD) in response to taxol treatment. In addition, polo-like kinase 1 (Plk1) failed to phosphorylate the Aur-A–unphosphorylatable FADD substitution mutant S203A, indicating that phosphorylation of S203 by Aur-A serves to prime FADD for Plk1-mediated phosphorylation at S194. The double-phosphorylation-mimicking mutant form of FADD, FADD-S194D/S203D (FADD-DD), recruited caspase-8, activating the caspase-dependent cell death pathway. FADD-DD also dissociated the cell death protein RIP1 from FADD, resulting in activation of RIP1 and triggering of caspase-independent cell death. Consistent with its death-promoting potential, FADD-DD showed robust tumor suppressor activity. However, single-phosphorylation-mimicking mutant forms of FADD, FADD-S194D/S203A (FADD-DA) and FADD-S194A/S203D (FADD-AD), were incapable of carrying out such functions, indicating that double phosphorylation of FADD is critical for the execution of cell death and tumor suppression. Collectively, our data show the existence of cooperative actions between Aur-A and Plk1 mitotic kinases in response to taxol, providing a molecular explanation for the action mechanism of taxol. Cancer Res; 71(23); 7207–15. ©2011 AACR.
Data from Genome-Wide Significant Association Between a Sequence Variant at 15q15.2 and Lung Cancer Risk
Authors: Rafnar Thorunn , Sulem Patrick , Besenbacher Soren , Gudbjartsson Daniel F. , Zanon Carlo , Gudmundsson Julius , Stacey Simon N. , Kostic Jelena P. , Thorgeirsson Thorgeir E. , Thorleifsson Gudmar , Bjarnason Hjordis , Skuladottir Halla , Gudbjartsson Tomas , Isaksson Helgi J. , Isla Dolores , Murillo Laura , García-Prats Maria D. , Panadero Angeles , Aben Katja K.H. , Vermeulen Sita H. , van der Heijden Henricus F.M. , Feser William J. , Miller York E. , Bunn Paul A. , Kong Augustine , Wolf Holly J. , Franklin Wilbur A. , Mayordomo Jose I. , Kiemeney Lambertus A. , Jonsson Steinn , Thorsteinsdottir Unnur , Stefansson Kari
Published: March 2024

Abstract
Genome-wide association studies (GWAS) have identified 3 genomic regions, at 15q24–25.1, 5p15.33, and 6p21.33, which associate with the risk of lung cancer. Large meta-analyses of GWA data have failed to find additional associations of genome-wide significance. In this study, we sought to confirm 7 variants with suggestive association to lung cancer (P < 10−5) in a recently published meta-analysis. In a GWA dataset of 1,447 lung cancer cases and 36,256 controls in Iceland, 3 correlated variants on 15q15.2 (rs504417, rs11853991, and rs748404) showed a significant association with lung cancer, whereas rs4254535 on 2p14, rs1530057 on 3p24.1, rs6438347 on 3q13.31, and rs1926203 on 10q23.31 did not. The most significant variant, rs748404, was genotyped in an additional 1,299 lung cancer cases and 4,102 controls from the Netherlands, Spain, and the United States and the results combined with published GWAS data. In this analysis, the T allele of rs748404 reached genome-wide significance (OR = 1.15, P = 1.1 × 10−9). Another variant at the same locus, rs12050604, showed association with lung cancer (OR = 1.09, 3.6 × 10−6) and remained significant after adjustment for rs748404 and vice versa. rs748404 is located 140 kb centromeric of the TP53BP1 gene that has been implicated in lung cancer risk. Two fully correlated, nonsynonymous coding variants in TP53BP1, rs2602141 (Q1136K) and rs560191 (E353D) showed association with lung cancer in our sample set; however, this association did not remain significant after adjustment for rs748404. Our data show that 1 or more lung cancer risk variants of genome-wide significance and distinct from the coding variants in TP53BP1 are located at 15q15.2. Cancer Res; 71(4); 1356–61. ©2011 AACR.
Data from IKKβ and NF-κB Transcription Govern Lymphoma Cell Survival through AKT-Induced Plasma Membrane Trafficking of GLUT1
Authors: Sommermann Thomas G. , O'Neill Kathleen , Plas David R. , Cahir-McFarland Ellen
Published: March 2024

Abstract
All cancer cells require increased nutrient uptake to support proliferation. In this study, we investigated the signals that govern glucose uptake in B-cell lymphomas and determined that the inhibitor of NF-κB-kinase β (IKKβ) induced glucose transporter-1 (GLUT1) membrane trafficking in both viral and spontaneous B-cell lymphomas. IKKβ induced AKT activity, whereas IKKβ-driven NF-κB transcription was required for GLUT1 surface localization downstream of AKT. Activated NF-κB promoted AKT-mediated phosphorylation of the GLUT1 regulator, AKT substrate of 160kD (AS160), but was not required for AKT phosphorylation of the mTOR regulator Tuberous Sclerosis 2 (TSC2). In Epstein-Barr virus–transformed B cells, NF-κB inhibition repressed glucose uptake and induced caspase-independent cell death associated with autophagy. After NF-κB inhibition, an alternate carbon source ameliorated both autophagy and cell death, whereas autophagy inhibitors specifically accelerated cell death. Taken together, the results indicate that NF-κB signaling establishes a metabolic program supporting proliferation and apoptosis resistance by driving glucose import. Cancer Res; 71(23); 7291–300. ©2011 AACR.
Data from Role of Heparanase in Radiation-Enhanced Invasiveness of Pancreatic Carcinoma
Authors: Meirovitz Amichay , Hermano Esther , Lerner Immanuel , Zcharia Eyal , Pisano Claudio , Peretz Tamar , Elkin Michael
Published: March 2024

Abstract
Pancreatic cancer is characterized by very low survival rates because of high intrinsic resistance to conventional therapies. Ionizing radiation (IR)–enhanced tumor invasiveness is emerging as one mechanism responsible for the limited benefit of radiotherapy in pancreatic cancer. In this study, we establish the role of heparanase—the only known mammalian endoglycosidase that cleaves heparan sulfate—in modulating the response of pancreatic cancer to radiotherapy. We found that clinically relevant doses of IR augment the invasive capability of pancreatic carcinoma cells in vitro and in vivo by upregulating heparanase. Changes in the levels of the transcription factor Egr-1 occurred in pancreatic cancer cells following radiation, underlying the stimulatory effect of IR on heparanase expression. Importantly, the specific heparanase inhibitor SST0001 abolished IR-enhanced invasiveness of pancreatic carcinoma cells in vitro, whereas combined treatment with SST0001 and IR, but not IR alone, attenuated the spread of orthotopic pancreatic tumors in vivo. Taken together, our results suggest that combining radiotherapy with heparanase inhibition is an effective strategy to prevent tumor resistance and dissemination, observed in many IR-treated pancreatic cancer patients. Further, the molecular mechanism underlying heparanase upregulation in pancreatic cancer that we identified in response to IR may help identify patients in which radiotherapeutic intervention may confer increased risk of metastatic spread, where antiheparanase therapy may be particularly beneficial. Cancer Res; 71(7); 2772–80. ©2011 AACR.
Data from Itraconazole Inhibits Angiogenesis and Tumor Growth in Non–Small Cell Lung Cancer
Authors: Aftab Blake T. , Dobromilskaya Irina , Liu Jun O. , Rudin Charles M.
Published: March 2024

Abstract
The antiangiogenic agent bevacizumab has been approved for the treatment of non–small cell lung cancer (NSCLC), although the survival benefit associated with this agent is marginal, and toxicities and cost are substantial. A recent screen for selective inhibitors of endothelial cell proliferation identified the oral antifungal drug itraconazole as a novel agent with potential antiangiogenic activity. In this article, we define and characterize the antiangiogenic and anticancer activities of itraconazole in relevant preclinical models of angiogenesis and lung cancer. Itraconazole consistently showed potent, specific, and dose-dependent inhibition of endothelial cell proliferation, migration, and tube formation in response to both VEGF- and basic fibroblast growth factor–mediated angiogenic stimulation. In vivo, using primary xenograft models of human NSCLC, oral itraconazole showed single-agent growth-inhibitory activity associated with induction of tumor hypoxia-inducible factor 1 alpha expression and marked inhibition of tumor vascularity. Itraconazole significantly enhanced the antitumor efficacy of the chemotherapeutic agent cisplatin in the same model systems. Taken together, these data suggest that itraconazole has potent and selective inhibitory activity against multiple key aspects of tumor-associated angiogenesis in vitro and in vivo, and strongly support clinical translation of its use. Based on these observations, we have initiated a randomized phase II study comparing the efficacy of standard cytotoxic therapy with or without daily oral itraconazole in patients with recurrent metastatic NSCLC. Cancer Res; 71(21); 6764–72. ©2011 AACR.
Data from p38γ Promotes Breast Cancer Cell Motility and Metastasis through Regulation of RhoC GTPase, Cytoskeletal Architecture, and a Novel Leading Edge Behavior
Authors: Rosenthal Devin T. , Iyer Harish , Escudero Silvia , Bao Liwei , Wu Zhifen , Ventura Alejandra C. , Kleer Celina G. , Arruda Ellen M. , Garikipati Krishna , Merajver Sofia D.
Published: March 2024

Abstract
Understanding the molecular alterations that confer cancer cells with motile, metastatic properties is needed to improve patient survival. Here, we report that p38γ motogen-activated protein kinase regulates breast cancer cell motility and metastasis, in part, by controlling expression of the metastasis-associated small GTPase RhoC. This p38γ–RhoC regulatory connection was mediated by a novel mechanism of modulating RhoC ubiquitination. This relationship persisted across multiple cell lines and in clinical breast cancer specimens. Using a computational mechanical model based on the finite element method, we showed that p38γ-mediated cytoskeletal changes are sufficient to control cell motility. This model predicted novel dynamics of leading edge actin protrusions, which were experimentally verified and established to be closely related to cell shape and cytoskeletal morphology. Clinical relevance was supported by evidence that elevated expression of p38γ is associated with lower overall survival of patients with breast cancer. Taken together, our results offer a detailed characterization of how p38γ contributes to breast cancer progression. Herein we present a new mechanics-based analysis of cell motility, and report on the discovery of a leading edge behavior in motile cells to accommodate modified cytoskeletal architecture. In summary, these findings not only identify a novel mechanism for regulating RhoC expression but also advance p38γ as a candidate therapeutic target. Cancer Res; 71(20); 6338–49. ©2011 AACR.
Data from Detection of Circulating Tumor Cells in Human Peripheral Blood Using Surface-Enhanced Raman Scattering Nanoparticles
Authors: Wang Xu , Qian Ximei , Beitler Jonathan J. , Chen Zhuo Georgia , Khuri Fadlo R. , Lewis Melinda M. , Shin Hyung Ju C. , Nie Shuming , Shin Dong M.
Published: March 2024

Abstract
The detection and characterization of circulating tumor cells (CTC) holds great promise for personalizing medicine and optimizing systemic therapy. However, low specificity, low sensitivity, and the time consuming nature of current approaches have impeded clinical adoption. Here we report a new method using surface-enhanced Raman spectroscopy (SERS) to directly measure targeted CTCs in the presence of white blood cells. SERS nanoparticles with epidermal growth factor peptide as a targeting ligand have successfully identified CTCs in the peripheral blood of 19 patients with squamous cell carcinoma of the head and neck (SCCHN), with a range of 1 to 720 CTCs per milliliter of whole blood. Our technique may provide an important new clinical tool for management of patients with SCCHN and other cancers. Cancer Res; 71(5); 1526–32. ©2011 AACR.
Data from Wnt/Snail Signaling Regulates Cytochrome c Oxidase and Glucose Metabolism
Authors: Lee Su Yeon , Jeon Hyun Min , Ju Min Kyung , Kim Cho Hee , Yoon Gyesoon , Han Song Iy , Park Hye Gyeong , Kang Ho Sung
Published: March 2024

Abstract
Wnt signaling plays a critical role in embryonic development, and its deregulation is closely linked to the occurrence of a number of malignant tumors, including breast and colon cancer. The pathway also induces Snail-dependent epithelial-to-mesenchymal transition (EMT), which is responsible for tumor invasion and metastasis. In this study, we show that Wnt suppresses mitochondrial respiration and cytochrome C oxidase (COX) activity by inhibiting the expression of 3 COX subunits, namely, COXVIc, COXVIIa, and COXVIIc. We found that Wnt induced a glycolytic switch via increased glucose consumption and lactate production, with induction of pyruvate carboxylase (PC), a key enzyme of anaplerosis. In addition, Wnt-induced mitochondrial repression and glycolytic switching occurred through the canonical β-catenin/T-cell factor 4/Snail pathway. Short hairpin RNA–mediated knockdown of E-cadherin, a regulator of EMT, repressed mitochondrial respiration and induced a glycolytic switch via Snail activation, indicating that EMT may contribute to Wnt/Snail regulation of mitochondrial respiration and glucose metabolism. Together, our findings provide a new function for Wnt/Snail signaling in the regulation of mitochondrial respiration (via COX gene expression) and glucose metabolism (via PC gene expression) in tumor growth and progression. Cancer Res; 72(14); 3607–17. ©2012 AACR.
Data from The Neuronal Differentiation Factor NeuroD1 Downregulates the Neuronal Repellent Factor Slit2 Expression and Promotes Cell Motility and Tumor Formation of Neuroblastoma
Authors: Huang Peng , Kishida Satoshi , Cao Dongliang , Murakami-Tonami Yuko , Mu Ping , Nakaguro Masato , Koide Naoshi , Takeuchi Ichiro , Onishi Akira , Kadomatsu Kenji
Published: March 2024

Abstract
The basic helix-loop-helix transcription factor NeuroD1 has been implicated in the neurogenesis and early differentiation of pancreatic endocrine cells. However, its function in relation to cancer has been poorly examined. In this study, we found that NeuroD1 is involved in the tumorigenesis of neuroblastoma. NeuroD1 was strongly expressed in a hyperplastic region comprising neuroblasts in the celiac sympathetic ganglion of 2-week-old MYCN transgenic (Tg) mice and was consistently expressed in the subsequently generated neuroblastoma tissue. NeuroD1 knockdown by short hairpin RNA (shRNA) resulted in motility inhibition of the human neuroblastoma cell lines, and this effect was reversed by shRNA-resistant NeuroD1. The motility inhibition by NeuroD1 knockdown was associated with induction of Slit2 expression, and knockdown of Slit2 could restore cell motility. Consistent with this finding, shRNA-resistant NeuroD1 suppressed Slit2 expression. NeuroD1 directly bound to the first and second E-box of the Slit2 promoter region. Moreover, we found that the growth of tumor spheres, established from neuroblastoma cell lines in MYCN Tg mice, was suppressed by NeuroD1 suppression. The functions identified for NeuroD1 in cell motility and tumor sphere growth may suggest a link between NeuroD1 and the tumorigenesis of neuroblastoma. Indeed, tumor formation of tumor sphere–derived cells was significantly suppressed by NeuroD1 knockdown. These data are relevant to the clinical features of human neuroblastoma: high NeuroD1 expression was closely associated with poor prognosis. Our findings establish the critical role of the neuronal differentiation factor NeuroD1 in neuroblastoma as well as its functional relationship with the neuronal repellent factor Slit2. Cancer Res; 71(8); 2938–48. ©2011 AACR.
Data from MicroRNA-301 Mediates Proliferation and Invasion in Human Breast Cancer
Authors: Shi Wei , Gerster Kate , Alajez Nehad M. , Tsang Jasmine , Waldron Levi , Pintilie Melania , Hui Angela B. , Sykes Jenna , P'ng Christine , Miller Naomi , McCready David , Fyles Anthony , Liu Fei-Fei
Published: March 2024

Abstract
Several microRNAs have been implicated in human breast cancer but none to date have been validated or utilized consistently in clinical management. MicroRNA-301 (miR-301) overexpression has been implicated as a negative prognostic indicator in lymph node negative (LNN) invasive ductal breast cancer, but its potential functional impact has not been determined. Here we report that in breast cancer cells, miR-301 attenuation decreased cell proliferation, clonogenicity, migration, invasion, tamoxifen resistance, tumor growth, and microvessel density, establishing an important oncogenic role for this gene. Algorithm-based and experimental strategies identified FOXF2, BBC3, PTEN, and COL2A1 as candidate miR-301 targets, all of which were verified as direct targets through luciferase reporter assays. We noted that miR-301 is located in an intron of the SKA2 gene which is responsible for kinetochore assembly, and both genes were found to be coexpressed in primary breast cancer samples. In summary, our findings define miR-301 as a crucial oncogene in human breast cancer that acts through multiple pathways and mechanisms to promote nodal or distant relapses. Cancer Res; 71(8); 2926–37. ©2011 AACR.
Data from Activation of the Glucocorticoid Receptor Is Associated with Poor Prognosis in Estrogen Receptor-Negative Breast Cancer
Authors: Pan Deng , Kocherginsky Masha , Conzen Suzanne D.
Published: March 2024

Abstract
Estrogen receptor–negative (ER−) breast cancers have limited treatment options and are associated with earlier relapses. Because glucocorticoid receptor (GR) signaling initiates antiapoptotic pathways in ER− breast cancer cells, we hypothesized that activation of these pathways might be associated with poor prognosis in ER− disease. Here we report findings from a genome-wide study of GR transcriptional targets in a premalignant ER− cell line model of early breast cancer (MCF10A-Myc) and in primary early-stage ER− human tumors. Chromatin immunoprecipitation with massively parallel sequencing (ChIP-seq) coupled to time-course expression profiling led us to identify epithelial-to-mesenchymal transition (EMT) pathways as an important aspect associated with GR activation. We validated these findings by carrying out a meta-analysis of primary breast tumor gene expression from 1,378 early-stage breast cancer patients with long-term clinical follow-up, confirming that high levels of GR expression significantly correlated with shorter relapse-free survival in ER− patients who were treated or untreated with adjuvant chemotherapy. Notably, in ER+ breast cancer patients, high levels of GR expression in tumors were significantly associated with better outcome relative to low levels of GR expression. Gene expression analysis revealed that ER− tumors expressing high GR levels exhibited differential activation of EMT, cell adhesion, and inflammation pathways. Our findings suggest a direct transcriptional role for GR in determining the outcome of poor-prognosis ER− breast cancers. Cancer Res; 71(20); 6360–70. ©2011 AACR.
Data from Oncogenic PI3K Mutations Lead to NF-κB–Dependent Cytokine Expression following Growth Factor Deprivation
Authors: Hutti Jessica E. , Pfefferle Adam D. , Russell Sean C. , Sircar Mayukh , Perou Charles M. , Baldwin Albert S.
Published: March 2024

Abstract
The phosphoinositide 3-kinase (PI3K) pathway is one of the most commonly misregulated signaling pathways in human cancers, but its impact on the tumor microenvironment has not been considered as deeply as its autonomous impact on tumor cells. In this study, we show that NF-κB is activated by the two most common PI3K mutations, PIK3CA E545K and H1047R. We found that markers of NF-κB are most strongly upregulated under conditions of growth factor deprivation. Gene expression analysis conducted on cells deprived of growth factors identified the repertoire of genes altered by oncogenic PI3K mutations following growth factor deprivation. This gene set most closely correlated with gene signatures from claudin-low and basal-like breast tumors, subtypes frequently exhibiting constitutive PI3K/Akt activity. An NF-κB–dependent subset of genes driven by oncogenic PI3K mutations was also identified that encoded primarily secreted proteins, suggesting a paracrine role for this gene set. Interestingly, while NF-κB activated by oncogenes such as Ras and EGF receptor leads to cell-autonomous effects, abrogating NF-κB in PI3K-transformed cells did not decrease proliferation or induce apoptosis. However, conditioned media from PI3K mutant-expressing cells led to increased STAT3 activation in recipient THP-1 monocytes or normal epithelial cells in a NF-κB and interleukin-6–dependent manner. Together, our findings describe a PI3K-driven, NF-κB–dependent transcriptional profile that may play a critical role in promoting a microenvironment amenable to tumor progression. These data also indicate that NF-κB plays diverse roles downstream from different oncogenic signaling pathways. Cancer Res; 72(13); 3260–9. ©2012 AACR.
Data from LOXL2-Mediated Matrix Remodeling in Metastasis and Mammary Gland Involution
Authors: Barker Holly E. , Chang Joan , Cox Thomas R. , Lang Georgina , Bird Demelza , Nicolau Monica , Evans Holly R. , Gartland Alison , Erler Janine T.
Published: March 2024

Abstract
More than 90% of cancer patient mortality is attributed to metastasis. In this study, we investigated a role for the lysyl oxidase-related enzyme lysyl oxidase-like 2 (LOXL2) in breast cancer metastasis, in both patient samples and in vivo models. Analysis of a published microarray data set revealed that LOXL2 expression is correlated with metastasis and decreased survival in patients with aggressive breast cancer. In immunocompetent or immunocompromised orthotopic and transgenic breast cancer models we showed that genetic, chemical or antibody-mediated inhibition of LOXL2 resulted in decreased metastasis. Mechanistic investigations revealed that LOXL2 promotes invasion by regulating the expression and activity of the extracellular proteins tissue inhibitor of metalloproteinase-1 (TIMP1) and matrix metalloproteinase-9 (MMP9). We found that LOXL2, TIMP1, and MMP9 are coexpressed during mammary gland involution, suggesting they function together in glandular remodeling after weaning. Finally, we found that LOXL2 is highly expressed in the basal/myoepithelial mammary cell lineage, like many other genes that are upregulated in basal-like breast cancers. Our findings highlight the importance of LOXL2 in breast cancer progression and support the development of anti-LOXL2 therapeutics for the treatment of metastatic breast cancer. Cancer Res; 71(5); 1561–72. ©2011 AACR.