bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from YB-1 Bridges Neural Stem Cells and Brain Tumor–Initiating Cells via Its Roles in Differentiation and Cell Growth
Authors: Fotovati Abbas , Abu-Ali Samah , Wang Pei-Shan , Deleyrolle Loic P. , Lee Cathy , Triscott Joanna , Chen James Y. , Franciosi Sonia , Nakamura Yasuhiro , Sugita Yasuo , Uchiumi Takeshi , Kuwano Michihiko , Leavitt Blair R. , Singh Sheila K. , Jury Alexa , Jones Chris , Wakimoto Hiroaki , Reynolds Brent A. , Pallen Catherine J. , Dunn Sandra E.
Published: March 2024

Abstract
The Y-box binding protein 1 (YB-1) is upregulated in many human malignancies including glioblastoma (GBM). It is also essential for normal brain development, suggesting that YB-1 is part of a neural stem cell (NSC) network. Here, we show that YB-1 was highly expressed in the subventricular zone (SVZ) of mouse fetal brain tissues but not in terminally differentiated primary astrocytes. Conversely, YB-1 knockout mice had reduced Sox-2, nestin, and musashi-1 expression in the SVZ. Although primary murine neurospheres were rich in YB-1, its expression was lost during glial differentiation. Glial tumors often express NSC markers and tend to loose the cellular control that governs differentiation; therefore, we addressed whether YB-1 served a similar role in cancer cells. YB-1, Sox-2, musashi-1, Bmi-1, and nestin are coordinately expressed in SF188 cells and 9/9 GBM patient-derived primary brain tumor–initiating cells (BTIC). Silencing YB-1 with siRNA attenuated the expression of these NSC markers, reduced neurosphere growth, and triggered differentiation via coordinate loss of GSK3-β. Furthermore, differentiation of BTIC with 1% serum or bone morphogenetic protein-4 suppressed YB-1 protein expression. Likewise, YB-1 expression was lost during differentiation of normal human NSCs. Consistent with these observations, YB-1 expression increased with tumor grade (n = 49 cases). YB-1 was also coexpressed with Bmi-1 (Spearmans 0.80, P > 0.001) and Sox-2 (Spearmans 0.66, P > 0.001) based on the analysis of 282 cases of high-grade gliomas. These proteins were highly expressed in 10/15 (67%) of GBM patients that subsequently relapsed. In conclusion, YB-1 correlatively expresses with NSC markers where it functions to promote cell growth and inhibit differentiation. Cancer Res; 71(16); 5569–78. ©2011 AACR.
Data from ROS and CHOP Are Critical for Dibenzylideneacetone to Sensitize Tumor Cells to TRAIL through Induction of Death Receptors and Downregulation of Cell Survival Proteins
Authors: Prasad Sahdeo , Yadav Vivek R. , Ravindran Jayaraj , Aggarwal Bharat B.
Published: March 2024

Abstract
Because tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) selectively kills tumor cells, it is being tested in cancer patients. Unfortunately, patients develop resistance to the cytokine, therefore, agents that can sensitize cells to TRAIL are urgently needed. In this study, we investigated whether dibenzylideneacetone (DBA) can sensitize cancer cells to TRAIL and potentiates TRAIL-induced apoptosis. As indicated by accumulation of the membrane phospholipid phosphatidylserine, DNA breaks, intracellular esterase activity, and activation of caspase-8, -9, and -3, we concluded that DBA potentiated TRAIL-induced apoptosis in colon cancer cells. DBA also converted TRAIL resistant-cells to TRAIL-sensitive. When examined for the mechanism, we found that DBA decreased the expression of antiapoptotic proteins and decoy recptor-2 and increased proapoptotic proteins. DBA also induced both death receptor (DR)-5 and DR4. Knockdown of DR5 and DR4 by small interfering RNA (SiRNA) reduced the sensitizing effect of DBA on TRAIL-induced apoptosis. In addition, DBA increased the expression of CHOP proteins. Knockdown of CHOP by siRNA decreased the induction of DBA-induced DR5 expression and apoptosis. Induction of receptors by DBA, however, was p53-independent, as deletion of p53 had no effect on receptor induction. We observed that DBA-induced induction of DR5 and DR4 was mediated through generation of reactive oxygen species (ROS), as N-acetylcysteine blocked the induction of death receptors and suppression of cell survival proteins by DBA. Overall, our results show that DBA potentiates TRAIL-induced apoptosis through downregulation of cell survival proteins and upregulation of death receptors via activation of ROS and CHOP mediated pathways. Cancer Res; 71(2); 538–49. ©2010 AACR.
Data from Tumor Suppressor miR-22 Determines p53-Dependent Cellular Fate through Post-transcriptional Regulation of p21
Authors: Tsuchiya Naoto , Izumiya Masashi , Ogata-Kawata Hiroko , Okamoto Koji , Fujiwara Yuko , Nakai Makiko , Okabe Atsushi , Schetter Aaron J. , Bowman Elise D. , Midorikawa Yutaka , Sugiyama Yasuyuki , Aburatani Hiroyuki , Harris Curtis C. , Nakagama Hitoshi
Published: March 2024

Abstract
Selective activation of p53 target genes in response to various cellular stresses is a critical step in determining the ability to induce cell-cycle arrest or apoptosis. Here we report the identification of the microRNA miR-22 as a p53 target gene that selectively determines the induction of p53-dependent apoptosis by repressing p21. Combinatorial analyses of the AGO2 immunocomplex and gene expression profiles identified p21 as a direct target of miR-22. Induction of p21 was inhibited by miR-22 after exposure to the genotoxic agent Adriamycin (doxorubicin; Bedford Laboratories), sensitizing cells to p53-dependent apoptosis. Interestingly, the activation of miR-22 depended on the intensity of the stresses that induced cells to undergo apoptosis in the presence of p21 suppression. Our findings define an intrinsic molecular switch that determines p53-dependent cellular fate through post-transcriptional regulation of p21. Cancer Res; 71(13); 4628–39. ©2011 AACR.
Data from Definition of an Enhanced Immune Cell Therapy in Mice That Can Target Stem-Like Lymphoma Cells
Authors: Contag Christopher H. , Sikorski Rachel , Negrin Robert S. , Schmidt Tobi , Fan Alice C. , Bachireddy Pavan , Felsher Dean W. , Thorne Steve H.
Published: March 2024

Abstract
Current treatments of high-grade lymphoma often have curative potential, but unfortunately many patients relapse and develop therapeutic resistance. Thus, there remains a need for novel therapeutics that can target the residual cancer cells whose phenotypes are distinct from the bulk tumor and that are capable of reforming tumors from very few cells. Oncolytic viruses offer an approach to destroy tumors by multiple mechanisms, but they cannot effectively reach residual disease or micrometastases, especially within the lymphatic system. To address these limitations, we have generated immune cells infected with oncolytic viruses as a therapeutic strategy that can combine effective cellular delivery with synergistic tumor killing. In this study, we tested this approach against minimal disease states of lymphomas characterized by the persistence of cancer cells that display stem cell–like properties and resistance to conventional therapies. We found that the immune cells were capable of trafficking to and targeting residual cancer cells. The combination biotherapy used prevented relapse by creating a long-term, disease-free state, with acquired immunity to the tumor functioning as an essential mediator of this effect. Immune components necessary for this acquired immunity were identified. We further demonstrated that the dual biotherapy could be applied before or after conventional therapy. Our approach offers a potentially powerful new way to clear residual cancer cells, showing how restoring immune surveillance is critical for maintenance of a disease-free state. Cancer Res; 70(23); 9837–45. ©2010 AACR.
Data from Delineation of a Cellular Hierarchy in Lung Cancer Reveals an Oncofetal Antigen Expressed on Tumor-Initiating Cells
Authors: Damelin Marc , Geles Kenneth G. , Follettie Maximillian T. , Yuan Ping , Baxter Michelle , Golas Jonathon , DiJoseph John F. , Karnoub Maha , Huang Shuguang , Diesl Veronica , Behrens Carmen , Choe Sung E. , Rios Carol , Gruzas Janet , Sridharan Latha , Dougher Maureen , Kunz Arthur , Hamann Philip R. , Evans Deborah , Armellino Douglas , Khandke Kiran , Marquette Kimberly , Tchistiakova Lioudmila , Boghaert Erwin R. , Abraham Robert T. , Wistuba Ignacio I. , Zhou Bin-Bing S.
Published: March 2024

Abstract
Poorly differentiated tumors in non–small cell lung cancer (NSCLC) have been associated with shorter patient survival and shorter time to recurrence following treatment. Here, we integrate multiple experimental models with clinicopathologic analysis of patient tumors to delineate a cellular hierarchy in NSCLC. We show that the oncofetal protein 5T4 is expressed on tumor-initiating cells and associated with worse clinical outcome in NSCLC. Coexpression of 5T4 and factors involved in the epithelial-to-mesenchymal transition were observed in undifferentiated but not in differentiated tumor cells. Despite heterogeneous expression of 5T4 in NSCLC patient–derived xenografts, treatment with an anti-5T4 antibody–drug conjugate resulted in complete and sustained tumor regression. Thus, the aggressive growth of heterogeneous solid tumors can be blocked by therapeutic agents that target a subpopulation of cells near the top of the cellular hierarchy. Cancer Res; 71(12); 4236–46. ©2011 AACR.
Data from miR-125b Is Methylated and Functions as a Tumor Suppressor by Regulating the ETS1 Proto-oncogene in Human Invasive Breast Cancer
Authors: Zhang Yan , Yan Li-Xu , Wu Qi-Nian , Du Zi-Ming , Chen Jing , Liao Ding-Zhun , Huang Ma-Yan , Hou Jing-Hui , Wu Qiu-Liang , Zeng Mu-Sheng , Huang Wen-Lin , Zeng Yi-Xin , Shao Jian-Yong
Published: March 2024

Abstract
The microRNA miR-125b is dysregulated in various human cancers but its underlying mechanisms of action are poorly understood. Here, we report that miR-125b is downregulated in invasive breast cancers where it predicts poor patient survival. Hypermethylation of the miR-125b promoter partially accounted for reduction of miR-125b expression in human breast cancer. Ectopic restoration of miR-125b expression in breast cancer cells suppressed proliferation, induced G1 cell-cycle arrest in vitro, and inhibited tumorigenesis in vivo. We identified the ETS1 gene as a novel direct target of miR-125b. siRNA-mediated ETS1 knockdown phenocopied the effect of miR-125b in breast cell lines and ETS1 overexpression in invasive breast cancer tissues also correlated with poor patient prognosis. Taken together, our findings point to an important role for miR-125b in the molecular etiology of invasive breast cancer, and they suggest miR-125b as a potential theranostic tool in this disease. Cancer Res; 71(10); 3552–62. ©2011 AACR.
Data from Inhibition of NEDD8-Activating Enzyme Induces Rereplication and Apoptosis in Human Tumor Cells Consistent with Deregulating CDT1 Turnover
Authors: Milhollen Michael A. , Narayanan Usha , Soucy Teresa A. , Veiby Petter O. , Smith Peter G. , Amidon Benjamin
Published: March 2024

Abstract
Loss of NEDD8-activating enzyme (NAE) function by siRNA knockdown or inhibition by the small molecule NAE inhibitor MLN4924 leads to increased steady-state levels of direct Cullin-RING ligase (CRL) substrates by preventing their ubiquitination and proteasome-dependent degradation. Many of these CRL substrates are involved in cell cycle progression, including a critical DNA replication licensing factor CDT1. Cell cycle analysis of asynchronous and synchronous cultures after NAE inhibition revealed effects on cell cycle distribution and activation of DNA break repair signaling pathways similar to that reported for CDT1 overexpression. The siRNA knockdown of cullins critical for the turnover of CDT1 recapitulated the aberrant rereplication phenotype while CDT1 knockdown was suppressing. Although NAE inhibition leads to deregulation of many CRL substrates, these data demonstrate that CDT1 accumulation mediates the DNA rereplication phenotype resulting from loss of NAE function. DNA rereplication is an unrecoverable cellular insult and the small molecule inhibitor MLN4924, currently in phase I trials, represents an unprecedented opportunity to explore this mechanism of cytotoxicity for the treatment of cancer. Cancer Res; 71(8); 3042–51. ©2011 AACR.
Data from Genetic Variation in an miRNA-1827 Binding Site in MYCL1 Alters Susceptibility to Small-Cell Lung Cancer
Authors: Xiong Fang , Wu Chen , Chang Jiang , Yu Dianke , Xu Binghe , Yuan Peng , Zhai Kan , Xu Jian , Tan Wen , Lin Dongxin
Published: March 2024

Abstract
Genetic variations in microRNAs (miRNA) that affect control of their target genes may alter individual susceptibilities to cancer. In this study, we took an in silico approach to identify single-nucleotide polymorphisms (SNP) within the 3′-untranslated region (UTR) of miRNA genes deregulated in human small-cell lung cancer (SCLC), and then investigated their associations with SCLC susceptibility in 666 SCLC patients and 758 controls. Odds ratios (OR) were estimated by multivariate logistic regression, and biochemical assays were conducted to investigate SNP functions. We identified 2 SNPs, rs3134615 and rs2291854, which were located in the 3′-UTR of the L-MYC gene MYCL1 and the neuronal development Achaete-Scute Complex homolog ASCL1. Case–control analyses showed that the rs3134615T allele was associated with a significantly increased risk of SCLC, with the OR for carrying the GT or TT genotype being 2.08 (95% confidence interval, 1.39–3.21; P = 0.0004) compared with the GG genotype. In support of the likelihood that these 3′-UTR SNPs may directly affect miRNA-binding sites, reporter gene assays indicated MYCL1 as the target of hsa-miR-1827 and the rs3134615 G>T change resulted in altered regulation of MYCL1 expression. Our findings define a 3′-UTR SNP in the human L-MYC oncogene that may increase susceptibility to SCLC, possibly resulting from attenuated interaction with the miRNA hsa-miR-1827. Cancer Res; 71(15); 5175–81. ©2011 AACR.
Data from Free Tubulin Modulates Mitochondrial Membrane Potential in Cancer Cells
Authors: Maldonado Eduardo N. , Patnaik Jyoti , Mullins Matthew R. , Lemasters John J.
Published: March 2024

Abstract
Formation of the mitochondrial membrane potential (ΔΨ) depends on flux of respiratory substrates, ATP, ADP, and Pi through voltage-dependent anion channels (VDAC). As tubulin promotes single-channel closure of VDAC, we hypothesized that tubulin is a dynamic regulator of ΔΨ, which in cultured cancer cells was assessed by confocal microscopy of the potential-indicating fluorophore tetramethylrhodamine methylester (TMRM). Microtubule destabilizers, rotenone, colchicine, and nocodazole, and the microtubule stabilizer paclitaxel increased and decreased cellular free tubulin, respectively, and in parallel decreased and increased ΔΨ. Protein kinase A (PKA) activation by cAMP analogues and glycogen synthase kinase 3β (GSK-3β) inhibition decreased ΔΨ, whereas PKA inhibition hyperpolarized, consistent with reports that PKA and GSK-3β decrease and increase VDAC conductance, respectively. Plasma membrane potential assessed by DiBAC4(3) was not altered by any of the treatments. We propose that inhibition of VDAC by free tubulin limits mitochondrial metabolism in cancer cells. Cancer Res; 70(24); 10192–201. ©2010 AACR.
Data from Frizzled 4 Regulates Stemness and Invasiveness of Migrating Glioma Cells Established by Serial Intracranial Transplantation
Authors: Jin Xun , Jeon Hee-Young , Joo Kyeung Min , Kim Jun-Kyum , Jin Juyoun , Kim Sung Hak , Kang Bong Gu , Beck Samuel , Lee Se Jeong , Kim Joong Kyu , Park Ae-Kyung , Park Woong-Yang , Choi Yun-Jaie , Nam Do-Hyun , Kim Hyunggee
Published: March 2024

Abstract
One of the most detrimental hallmarks of glioblastoma multiforme (GBM) is cellular invasiveness, which is considered a potential cause of tumor recurrence. Infiltrated GBM cells are difficult to completely eradicate surgically and with local therapeutic modalities. Although much effort has focused on understanding the various mechanisms controlling GBM invasiveness, its nature remains poorly understood. In this study, we established highly serial intracranial transplantation. U87R4 cells were highly invasive and displayed stem cell-like properties, as compared to noninvasive but proliferative U87L4 cells. Microarray analysis during serial transplantation revealed that apoptosis-inducing genes (caspase3 and PDCD4) were downregulated whereas several cancer stem cell–relevant genes [Frizzled 4 (FZD4) and CD44] were upregulated in more invasive cells. U87R4 cells were resistant to anticancer drug–induced cell death, partly due to downregulation of caspase3 and PDCD4, and they retained activated Wnt/β-catenin signaling due to upregulation of Frizzled 4, which was sufficient to control neurosphere formation. We also found that FZD4 promoted expression of the epithelial to mesenchymal transition regulator SNAI1, along with acquisition of a mesenchymal phenotype. Taken together, our results argue that Frizzled 4 is a member of the Wnt signaling family that governs both stemness and invasiveness of glioma stem cells, and that it may be a major cause of GBM recurrence and poor prognosis. Cancer Res; 71(8); 3066–75. ©2011 AACR.
Data from Increased VEGFR-2 Gene Copy Is Associated with Chemoresistance and Shorter Survival in Patients with Non–Small-Cell Lung Carcinoma Who Receive Adjuvant Chemotherapy
Authors: Yang Fei , Tang Ximing , Riquelme Erick , Behrens Carmen , Nilsson Monique B. , Giri Uma , Varella-Garcia Marileila , Byers Lauren A. , Lin Heather Y. , Wang Jing , Raso Maria G. , Girard Luc , Coombes Kevin , Lee J. Jack , Herbst Roy S. , Minna John D. , Heymach John V. , Wistuba Ignacio I.
Published: March 2024

Abstract
VEGF receptor-2 (VEGFR-2 or kinase insert domain receptor; KDR) is a known endothelial target also expressed in NSCLC tumor cells. We investigated the association between alterations in the KDR gene and clinical outcome in patients with resected non–small-cell lung carcinoma (NSCLC; n = 248). KDR copy number gains (CNG), measured by quantitative PCR and fluorescence in situ hybridization, were detected in 32% of tumors and associated with significantly higher KDR protein and higher microvessel density than tumors without CNGs. KDR CNGs were also associated with significantly increased risk of death (HR = 5.16; P = 0.003) in patients receiving adjuvant platinum-based chemotherapy, but no differences were observed in patients not receiving adjuvant therapy. To investigate potential mechanisms for these associations, we assessed NSCLC cell lines and found that KDR CNGs were significantly associated with in vitro resistance to platinum chemotherapy as well as increased levels of nuclear hypoxia inducible factor-1α (HIF-1α) in both NSCLC tumor specimens and cell lines. Furthermore, KDR knockdown experiments using small interfering RNA reduced platinum resistance, cell migration, and HIF-1α levels in cells bearing KDR CNGs, providing evidence for direct involvement of KDR. No KDR mutations were detected in exons 7, 11, and 21 by PCR-based sequencing; however, two variant single nucleotide polymorphism genotypes were associated with favorable overall survival in adenocarcinoma patients. Our findings suggest that tumor cell KDR CNGs may promote a more malignant phenotype including increased chemoresistance, angiogenesis, and HIF-1α levels, and that KDR CNGs may be a useful biomarker for identifying patients at high risk for recurrence after adjuvant therapy, a group that may benefit from VEGFR-2 blockade. Cancer Res; 71(16); 5512–21. ©2011 AACR.
Data from Blocking Hypoxia-Induced Autophagy in Tumors Restores Cytotoxic T-Cell Activity and Promotes Regression
Authors: Noman Muhammad Zaeem , Janji Bassam , Kaminska Bozena , Van Moer Kris , Pierson Sandrine , Przanowski Piotr , Buart Stéphanie , Berchem Guy , Romero Pedro , Mami-Chouaib Fathia , Chouaib Salem
Published: March 2024

Abstract
The relationship between hypoxic stress, autophagy, and specific cell-mediated cytotoxicity remains unknown. This study shows that hypoxia-induced resistance of lung tumor to cytolytic T lymphocyte (CTL)–mediated lysis is associated with autophagy induction in target cells. In turn, this correlates with STAT3 phosphorylation on tyrosine 705 residue (pSTAT3) and HIF-1α accumulation. Inhibition of autophagy by siRNA targeting of either beclin1 or Atg5 resulted in impairment of pSTAT3 and restoration of hypoxic tumor cell susceptibility to CTL-mediated lysis. Furthermore, inhibition of pSTAT3 in hypoxic Atg5 or beclin1-targeted tumor cells was found to be associated with the inhibition Src kinase (pSrc). Autophagy-induced pSTAT3 and pSrc regulation seemed to involve the ubiquitin proteasome system and p62/SQSTM1. In vivo experiments using B16-F10 melanoma tumor cells indicated that depletion of beclin1 resulted in an inhibition of B16-F10 tumor growth and increased tumor apoptosis. Moreover, in vivo inhibition of autophagy by hydroxychloroquine in B16-F10 tumor-bearing mice and mice vaccinated with tyrosinase-related protein-2 peptide dramatically increased tumor growth inhibition. Collectively, this study establishes a novel functional link between hypoxia-induced autophagy and the regulation of antigen-specific T-cell lysis and points to a major role of autophagy in the control of in vivo tumor growth. Cancer Res; 71(18); 5976–86. ©2011 AACR.
Data from The Tumor Suppressive MicroRNA miR-218 Targets the mTOR Component Rictor and Inhibits AKT Phosphorylation in Oral Cancer
Authors: Uesugi Atsushi , Kozaki Ken-ichi , Tsuruta Tomohiko , Furuta Mayuko , Morita Kei-ichi , Imoto Issei , Omura Ken , Inazawa Johji
Published: March 2024

Abstract
The incidence of oral squamous cell carcinoma (OSCC) is rising rapidly in developed countries, posing a growing challenge due to the poor management of this type of malignancy at present. In this study, we profiled tumor suppressive microRNAs (miRNAs) that are silenced by DNA hypermethylation in OSCC using a function-based screening approach. This approach employed a cell proliferation assay for 327 synthetic miRNAs in two OSCC cell lines. Among the 110 miRNAs identified in this set that exhibited inhibitory properties, we compared DNA methylation and expression status in a wider panel of OSCC cell lines and primary tumor tissues, resulting in the identification of miR-218 and miR-585 as functionally significant miRNA genes that are frequently silenced in OSCC by DNA hypermethylation. Ectopic expression of miR-218 and miR-585 in OSCC cells lacking endogenous expression reduced cell growth in part through caspase-mediated apoptosis. Notably, miR-218 reduced levels of the rapamycin-insensitive component of mTOR, Rictor, in a manner associated with a suppression of Akt S473 phosphorylation. Together our findings define miR-585 as a tumor suppressive function that is often epigenetically silenced in OSCC, and they identify Rictor as a novel target of miR-218, suggesting that activation of the mTOR-Akt signaling pathway induced by Rictor contributes centrally to oral carcinogenesis. Cancer Res; 71(17); 5765–78. ©2011 AACR.
Data from Endothelial Cells Create a Stem Cell Niche in Glioblastoma by Providing NOTCH Ligands That Nurture Self-Renewal of Cancer Stem-Like Cells
Authors: Zhu Thant S. , Costello Mark A. , Talsma Caroline E. , Flack Callie G. , Crowley Jessica G. , Hamm Lisa L. , He Xiaobing , Hervey-Jumper Shawn L. , Heth Jason A. , Muraszko Karin M. , DiMeco Francesco , Vescovi Angelo L. , Fan Xing
Published: March 2024

Abstract
One important function of endothelial cells in glioblastoma multiforme (GBM) is to create a niche that helps promote self-renewal of cancer stem-like cells (CSLC). However, the underlying molecular mechanism for this endothelial function is not known. Since activation of NOTCH signaling has been found to be required for propagation of GBM CSLCs, we hypothesized that the GBM endothelium may provide the source of NOTCH ligands. Here, we report a corroboration of this concept with a demonstration that NOTCH ligands are expressed in endothelial cells adjacent to NESTIN and NOTCH receptor-positive cancer cells in primary GBMs. Coculturing human brain microvascular endothelial cells (hBMEC) or NOTCH ligand with GBM neurospheres promoted GBM cell growth and increased CSLC self-renewal. Notably, RNAi-mediated knockdown of NOTCH ligands in hBMECs abrogated their ability to induce CSLC self-renewal and GBM tumor growth, both in vitro and in vivo. Thus, our findings establish that NOTCH activation in GBM CSLCs is driven by juxtacrine signaling between tumor cells and their surrounding endothelial cells in the tumor microenvironment, suggesting that targeting both CSLCs and their niche may provide a novel strategy to deplete CSLCs and improve GBM treatment. Cancer Res; 71(18); 6061–72. ©2011 AACR.
Data from Multiple Injections of Electroporated Autologous T Cells Expressing a Chimeric Antigen Receptor Mediate Regression of Human Disseminated Tumor
Authors: Zhao Yangbing , Moon Edmund , Carpenito Carmine , Paulos Chrystal M. , Liu Xiaojun , Brennan Andrea L. , Chew Anne , Carroll Richard G. , Scholler John , Levine Bruce L. , Albelda Steven M. , June Carl H.
Published: March 2024

Abstract
Redirecting T lymphocyte antigen specificity by gene transfer can provide large numbers of tumor-reactive T lymphocytes for adoptive immunotherapy. However, safety concerns associated with viral vector production have limited clinical application of T cells expressing chimeric antigen receptors (CAR). T lymphocytes can be gene modified by RNA electroporation without integration-associated safety concerns. To establish a safe platform for adoptive immunotherapy, we first optimized the vector backbone for RNA in vitro transcription to achieve high-level transgene expression. CAR expression and function of RNA-electroporated T cells could be detected up to a week after electroporation. Multiple injections of RNA CAR–electroporated T cells mediated regression of large vascularized flank mesothelioma tumors in NOD/scid/γc(−/−) mice. Dramatic tumor reduction also occurred when the preexisting intraperitoneal human-derived tumors, which had been growing in vivo for >50 days, were treated by multiple injections of autologous human T cells electroporated with anti-mesothelin CAR mRNA. This is the first report using matched patient tumor and lymphocytes showing that autologous T cells from cancer patients can be engineered to provide an effective therapy for a disseminated tumor in a robust preclinical model. Multiple injections of RNA-engineered T cells are a novel approach for adoptive cell transfer, providing flexible platform for the treatment of cancer that may complement the use of retroviral and lentiviral engineered T cells. This approach may increase the therapeutic index of T cells engineered to express powerful activation domains without the associated safety concerns of integrating viral vectors. Cancer Res; 70(22); 9053–61. ©2010 AACR.
Data from Tumor Microenvironment–Derived Proteins Dominate the Plasma Proteome Response during Breast Cancer Induction and Progression
Authors: Pitteri Sharon J. , Kelly-Spratt Karen S. , Gurley Kay E. , Kennedy Jacob , Buson Tina Busald , Chin Alice , Wang Hong , Zhang Qing , Wong Chee-Hong , Chodosh Lewis A. , Nelson Peter S. , Hanash Samir M. , Kemp Christopher J.
Published: March 2024

Abstract
Tumor development relies upon essential contributions from the tumor microenvironment and host immune alterations. These contributions may inform the plasma proteome in a manner that could be exploited for cancer diagnosis and prognosis. In this study, we employed a systems biology approach to characterize the plasma proteome response in the inducible HER2/neu mouse model of breast cancer during tumor induction, progression, and regression. Mass spectrometry data derived from approximately 1.6 million spectra identified protein networks involved in wound healing, microenvironment, and metabolism that coordinately changed during tumor development. The observed alterations developed prior to cancer detection, increased progressively with tumor growth and reverted toward baseline with tumor regression. Gene expression and immunohistochemical analyses suggested that the cancer-associated plasma proteome was derived from transcriptional responses in the noncancerous host tissues as well as the developing tumor. The proteomic signature was distinct from a nonspecific response to inflammation. Overall, the developing tumor simultaneously engaged a number of innate physiologic processes, including wound repair, immune response, coagulation and complement cascades, tissue remodeling, and metabolic homeostasis that were all detectable in plasma. Our findings offer an integrated view of tumor development relevant to plasma-based strategies to detect and diagnose cancer. Cancer Res; 71(15); 5090–100. ©2011 AACR.
Data from DLL4-Notch Signaling Mediates Tumor Resistance to Anti-VEGF Therapy In Vivo
Authors: Li Ji-Liang , Sainson Richard C.A. , Oon Chern Ein , Turley Helen , Leek Russell , Sheldon Helen , Bridges Esther , Shi Wen , Snell Cameron , Bowden Emma T. , Wu Herren , Chowdhury Partha S. , Russell Angela J. , Montgomery Craig P. , Poulsom Richard , Harris Adrian L.
Published: March 2024

Abstract
Resistance to VEGF inhibitors is emerging as a major clinical problem. Notch signaling has been implicated in tumor angiogenesis. Therefore, to investigate mechanisms of resistance to angiogenesis inhibitors, we transduced human glioblastoma cells with retroviruses encoding Notch delta-like ligand 4 (DLL4), grew them as tumor xenografts and then treated the murine hosts with the VEGF-A inhibitor bevacizumab. We found that DLL4-mediated tumor resistance to bevacizumab in vivo. The large vessels induced by DLL4-Notch signaling increased tumor blood supply and were insensitive to bevacizumab. However, blockade of Notch signaling by dibenzazepine, a γ-secretase inhibitor, disrupted the large vessels and abolished the tumor resistance. Multiple molecular mechanisms of resistance were shown, including decreased levels of hypoxia-induced VEGF and increased levels of the VEGF receptor VEGFR1 in the tumor stroma, decreased levels of VEGFR2 in large blood vessels, and reduced levels of VEGFR3 overall. DLL4-expressing tumors were also resistant to a VEGFR targeting multikinase inhibitor. We also observed activation of other pathways of tumor resistance driven by DLL4-Notch signaling, including the FGF2-FGFR and EphB4-EprinB2 pathways, the inhibition of which reversed tumor resistance partially. Taken together, our findings show the importance of classifying mechanisms involved in angiogenesis in tumors, and how combination therapy to block DLL4-Notch signaling may enhance the efficacy of VEGF inhibitors, particularly in DLL4-upregulated tumors, and thus provide a rational base for the development of novel strategies to overcome antiangiogenic resistance in the clinic. Cancer Res; 71(18); 6073–83. ©2011 AACR.
Data from Reprogramming CD19-Specific T Cells with IL-21 Signaling Can Improve Adoptive Immunotherapy of B-Lineage Malignancies
Authors: Singh Harjeet , Figliola Matthew J. , Dawson Margaret J. , Huls Helen , Olivares Simon , Switzer Kirsten , Mi Tiejuan , Maiti Sourindra , Kebriaei Partow , Lee Dean A. , Champlin Richard E. , Cooper Laurence J.N.
Published: March 2024

Abstract
Improving the therapeutic efficacy of T cells expressing a chimeric antigen receptor (CAR) represents an important goal in efforts to control B-cell malignancies. Recently an intrinsic strategy has been developed to modify the CAR itself to improve T-cell signaling. Here we report a second extrinsic approach based on altering the culture milieu to numerically expand CAR+ T cells with a desired phenotype, for the addition of interleukin (IL)-21 to tissue culture improves CAR-dependent T-cell effector functions. We used electrotransfer of Sleeping Beauty system to introduce a CAR transposon and selectively propagate CAR+ T cells on CD19+ artificial antigen-presenting cells (aAPC). When IL-21 was present, there was preferential numeric expansion of CD19-specific T cells which lysed and produced IFN-γ in response to CD19. Populations of these numerically expanded CAR+ T cells displayed an early memory surface phenotype characterized as CD62L+CD28+ and a transcriptional profile of naïve T cells. In contrast, T cells propagated with only exogenous IL-2 tended to result in an overgrowth of CD19-specific CD4+ T cells. Furthermore, adoptive transfer of CAR+ T cells cultured with IL-21 exhibited improved control of CD19+ B-cell malignancy in mice. To provide coordinated signaling to propagate CAR+ T cells, we developed a novel mutein of IL-21 bound to the cell surface of aAPC that replaced the need for soluble IL-21. Our findings show that IL-21 can provide an extrinsic reprogramming signal to generate desired CAR+ T cells for effective immunotherapy. Cancer Res; 71(10); 3516–27. ©2011 AACR.
Data from Nuclear ErbB2 Enhances Translation and Cell Growth by Activating Transcription of Ribosomal RNA Genes
Authors: Li Long-Yuan , Chen Hsiuyi , Hsieh Yi-Hsien , Wang Ying-Nai , Chu Hsiao-Ju , Chen Ya-Huey , Chen Hui-Yu , Chien Peng-Ju , Ma Haou-Tzong , Tsai Ho-Cheng , Lai Chien-Chen , Sher Yuh-Pyng , Lien Huang-Chun , Tsai Chang-Hai , Hung Mien-Chie
Published: March 2024

Abstract
Aberrant regulation of rRNA synthesis and translation control can facilitate tumorigenesis. The ErbB2 growth factor receptor is overexpressed in many human tumors and has been detected in the nucleus, but the role of nuclear ErbB2 is obscure. In this study, we defined a novel function of nuclear ErbB2 in enhancing rRNA gene transcription by RNA polymerase-I (RNA Pol I). Nuclear ErbB2 physically associates with β-actin and RNA Pol I, coinciding with active RNA Pol I transcription sites in nucleoli. RNA interference–mediated knockdown of ErbB2 reduced pre-rRNA and protein synthesis. In contrast, wild-type ErbB2 augmented pre-rRNA level, protein production, and cell size/cell growth, but not by an ErbB2 mutant that is defective in nuclear translocation. Chromatin immunoprecipitation assays revealed that ErbB2 enhances binding of RNA Pol I to rDNA. In addition, ErbB2 associated with rDNA, RNA Pol I, and β-actin, suggesting how it could stimulate rRNA production, protein synthesis, and increased cell size and cell growth. Finally, ErbB2-potentiated RNA Pol I transcription could be stimulated by ligand and was not substantially repressed by inhibition of PI3-K and MEK/ERK (extracellular signal regulated kinase), the main ErbB2 effector signaling pathways. Together, our findings indicate that nuclear ErbB2 functions as a regulator of rRNA synthesis and cellular translation, which may contribute to tumor development and progression. Cancer Res; 71(12); 4269–79. ©2011 AACR.
Data from Sirtuin 1 Is Upregulated in a Subset of Hepatocellular Carcinomas where It Is Essential for Telomere Maintenance and Tumor Cell Growth
Authors: Chen Juan , Zhang Bin , Wong Nathalie , Lo Anthony W.I. , To Ka-Fai , Chan Anthony W.H. , Ng Margaret H.L. , Ho Cecilia Y.S. , Cheng Suk-Hang , Lai Paul B.S. , Yu Jun , Ng Ho-Keung , Ling Ming-Tat , Huang Ai-Long , Cai Xue-Fei , Ko Ben C.B.
Published: March 2024

Abstract
Hepatocellular carcinoma (HCC) is a highly malignant tumor with a poor prognosis. Treatment of HCC is complicated by the fact that the disease is often diagnosed at an advanced stage when it is no longer amenable to curative surgery, and current systemic chemotherapeutics are mostly inefficacious. Sirtuin 1 (SIRT1) is a class III histone deacetylase that is implicated in gene regulations and stress resistance. In this study, we found that SIRT1 is essential for the tumorigenesis of HCC. We showed that although SIRT1 was expressed at very low levels in normal livers, it was overexpressed in HCC cell lines and in a subset of HCC. Tissue microarray analysis of HCC and adjacent nontumoral liver tissues revealed a positive correlation between the expression levels of SIRT1 and advancement in tumor grades. Downregulation of SIRT1 consistently suppressed the proliferation of HCC cells via the induction of cellular senescence or apoptosis. SIRT1 silencing also caused telomere dysfunction–induced foci and nuclear abnormality that were clearly associated with reduced expressions of telomerase reverse transcriptase (TERT), and PTOP, which is a member of the shelterin complex. Ectopic expression of either TERT or PTOP in SIRT1-depleted cells significantly restored cell proliferation. There was also a positive correlation between the level of induction of SIRT1 and PTOP in human HCC. Finally, SIRT1-silencing sensitized HCC cells to doxorubicin treatment. Together, our findings reveal a novel function for SIRT1 in telomere maintenance of HCC, and they rationalize the clinical exploration of SIRT1 inhibitors for HCC therapy. Cancer Res; 71(12); 4138–49. ©2011 AACR.
Data from MRE11 Deficiency Increases Sensitivity to Poly(ADP-ribose) Polymerase Inhibition in Microsatellite Unstable Colorectal Cancers
Authors: Vilar Eduardo , Bartnik Catherine M. , Stenzel Stephanie L. , Raskin Leon , Ahn Jaeil , Moreno Victor , Mukherjee Bhramar , Iniesta Maria D. , Morgan Meredith A. , Rennert Gad , Gruber Stephen B.
Published: March 2024

Abstract
Microsatellite instability (MSI) is displayed by approximately 15% of colorectal cancers (CRC). Defective DNA mismatch repair generates mutations at repetitive DNA sequences such as those located in the double strand break (DSB) repair gene MRE11. We assessed the mutational status of MRE11 in a panel of 17 CRC cell lines and 46 primary tumors and found a strong correlation with MSI status in both cell lines and tumors. Therefore, we hypothesized that deficiency in MRE11 may sensitize CRC cells to poly(ADP-ribose) polymerase (PARP-1) inhibition based on the concept of synthetic lethality. We further assessed the activity of the PARP-1 inhibitor, ABT-888, in CRC cell lines and observed preferential cytotoxicity in those MSI cell lines harboring mutations in MRE11 compared with both wild-type cell lines and microsatellite stable (MSS) cell lines. A significant correlation between MRE11 expression levels and cytotoxicity to ABT-888 at 10 μM was observed (R2 = 0.915, P < 0.001). Using two experimental approaches, including short hairpin RNA knocking down MRE11 in the wild-type and MSS cell line SW-480 and a second cell line model transfected with mutant MRE11, we experimentally tried to confirm the role of MRE11 in conferring sensitivity to PARP-1 inhibition. Both models led to changes in proliferation in response to ABT-888 at different concentrations, and a drug–response effect was not observed, suggesting a possible contribution of additional genes. We conclude that MSI colorectal tumors deficient in DSB repair secondary to mutation in MRE11 show a higher sensitivity to PARP-1 inhibition. Further clinical investigation of PARP-1 inhibitors is warranted in MSI CRCs. Cancer Res; 71(7); 2632–42. ©2011 AACR.
Data from Bcl-2 Inhibits Nuclear Homologous Recombination by Localizing BRCA1 to the Endomembranes
Authors: Laulier Corentin , Barascu Aurélia , Guirouilh-Barbat Josée , Pennarun Gaëlle , Le Chalony Catherine , Chevalier François , Palierne Gaëlle , Bertrand Pascale , Verbavatz Jean Marc , Lopez Bernard S.
Published: March 2024

Abstract
Genetic stability requires coordination of a network of pathways including DNA repair/recombination and apoptosis. In addition to its canonical anti-apoptotic role, Bcl-2 negatively impacts genome stability. In this study, we identified the breast cancer tumor suppressor BRCA1, which plays an essential role in homologous recombination (HR), as a target for Bcl-2 in the repression of HR. Indeed, ionizing radiation–induced BRCA1 foci assembly was repressed when Bcl-2 was expressed ectopically, in human SV40 fibroblasts, or spontaneously, in lymphoma t(14:18) cells and in HeLa and H460 cancer cell lines. Moreover, we showed that the transmembrane (TM) domain of Bcl-2 was required for both inhibition of BRCA1 foci assembly and the inhibition of HR induced by a double-strand break targeted into an intrachromosomal HR substrate by the meganuclease I-SceI. Fluorescence confocal microscopy, proximity ligation assay, and electron microscopy analyses as well as Western blot analysis of subcellular fractions showed that Bcl-2 and BRCA1 colocalized to mitochondria and endoplasmic reticulum in a process requiring the TM domain of Bcl-2. Targeting BRCA1 to the endomembranes depletes BRCA1 from the nucleus and, thus, accounts for the inhibition of HR. Furthermore, our findings support an apoptosis-stimulatory role for the cytosolic form of BRCA1, suggesting a new tumor suppressor function of BRCA1. Together, our results reveal a new mode of BRCA1 regulation and for HR in the maintenance of genome stability. Cancer Res; 71(10); 3590–602. ©2011 AACR.
Data from EGF Receptor Inhibition Radiosensitizes NSCLC Cells by Inducing Senescence in Cells Sustaining DNA Double-Strand Breaks
Authors: Wang Meng , Morsbach Fabian , Sander David , Gheorghiu Liliana , Nanda Akash , Benes Cyril , Kriegs Malte , Krause Mechthild , Dikomey Ekkehard , Baumann Michael , Dahm-Daphi Jochen , Settleman Jeffrey , Willers Henning
Published: March 2024

Abstract
The mechanisms by which inhibition of the epidermal growth factor receptor (EGFR) sensitizes non–small cell lung cancer (NSCLC) cells to ionizing radiation remain poorly understood. We set out to characterize the radiosensitizing effects of the tyrosine kinase inhibitor erlotinib and the monoclonal antibody cetuximab in NSCLC cells that contain wild-type p53. Unexpectedly, EGFR inhibition led to pronounced cellular senescence but not apoptosis of irradiated cells, both in vitro and in vivo. Senescence was completely dependent on wild-type p53 and associated with a reduction in cell number as well as impaired clonogenic radiation survival. Study of ten additional NSCLC cell lines revealed that senescence is a prominent mechanism of radiosensitization in 45% of cell lines and occurs not only in cells with wild-type p53 but also in cells with mutant p53, where it is associated with an induction of p16. Interestingly, senescence and radiosensitization were linked to an increase in residual radiation-induced DNA double-strand breaks irrespective of p53/p16 status. This effect of EGFR inhibition was at least partially mediated by disruption of the MEK–ERK pathway. Thus, our data indicate a common mechanism of radiosensitization by erlotinib or cetuximab across diverse genetic backgrounds. Our findings also suggest that assays that are able to capture the initial proliferative delay that is associated with senescence should be useful for screening large cell line panels to identify genomic biomarkers of EGFR inhibitor–mediated radiosensitization. Cancer Res; 71(19); 6261–9. ©2011 AACR.
Data from Overcoming Trastuzumab Resistance in Breast Cancer by Targeting Dysregulated Glucose Metabolism
Authors: Zhao Yuhua , Liu Hao , Liu Zixing , Ding Yan , LeDoux Susan P. , Wilson Glenn L. , Voellmy Richard , Lin Yifeng , Lin Wensheng , Nahta Rita , Liu Bolin , Fodstad Oystein , Chen Jieqing , Wu Yun , Price Janet E. , Tan Ming
Published: March 2024

Abstract
Trastuzumab shows remarkable efficacy in treatment of ErbB2-positive breast cancers when used alone or in combination with other chemotherapeutics. However, acquired resistance develops in most treated patients, necessitating alternate treatment strategies. Increased aerobic glycolysis is a hallmark of cancer and inhibition of glycolysis may offer a promising strategy to preferentially kill cancer cells. In this study, we investigated the antitumor effects of trastuzumab in combination with glycolysis inhibitors in ErbB2-positive breast cancer. We found that trastuzumab inhibits glycolysis via downregulation of heat shock factor 1 (HSF1) and lactate dehydrogenase A (LDH-A) in ErbB2-positive cancer cells, resulting in tumor growth inhibition. Moreover, increased glycolysis via HSF1 and LDH-A contributes to trastuzumab resistance. Importantly, we found that combining trastuzumab with glycolysis inhibition synergistically inhibited trastuzumab-sensitive and -resistant breast cancers in vitro and in vivo, due to more efficient inhibition of glycolysis. Taken together, our findings show how glycolysis inhibition can dramatically enhance the therapeutic efficacy of trastuzumab in ErbB2-positive breast cancers, potentially useful as a strategy to overcome trastuzumab resistance. Cancer Res; 71(13); 4585–97. ©2011 AACR.
Data from IL-12 Release by Engineered T Cells Expressing Chimeric Antigen Receptors Can Effectively Muster an Antigen-Independent Macrophage Response on Tumor Cells That Have Shut Down Tumor Antigen Expression
Authors: Chmielewski Markus , Kopecky Caroline , Hombach Andreas A. , Abken Hinrich
Published: March 2024

Abstract
During malignant progression cancer cells tend to lose cell surface expression of MHC and other immune antigens, making them invisible to cytotoxic T cells and therefore inaccessible to tumor antigen-directed immunotherapy. Moreover, cancer cell variants that have lost antigen expression frequently contribute to deadly tumor relapses that occur following treatments that had been initially effective. In an effort to destroy antigen-loss cancer cells in tumors, we created a strategy that combines a chimeric antigen receptor (CAR)-redirected T-cell attack with an engineered local release of the cytokine interleukin 12 (IL-12), which recruits and reinforces macrophage function. Cytotoxic T cells were engineered to release inducible IL-12 upon CAR engagement in the tumor lesion, resulting in destruction of antigen-loss cancer cells that would normally escape. Importantly, elimination of the antigen-loss cancer cells was accompanied by an accumulation of activated macrophages that was critical to the antitumor response, because removing the macrophages abolished the response and restoring them reengaged it. Neutralizing TNF-α also abrogated the elimination of antigen-loss cancer cells, implying this proinflammatory factor in the process. Taken together, our results show how IL-12 supplementation by CAR T cells can target otherwise inaccessible tumor lesions, in a manner associated with reduced systemic toxicity, by recruiting and activating innate immune cells for a proinflammatory response. Cancer Res; 71(17); 5697–706. ©2011 AACR.
Data from Luminal Expression of PIK3CA Mutant H1047R in the Mammary Gland Induces Heterogeneous Tumors
Authors: Meyer Dominique S. , Brinkhaus Heike , Müller Urs , Müller Matthias , Cardiff Robert D. , Bentires-Alj Mohamed
Published: March 2024

Abstract
The phosphoinositide 3-kinase (PI3K) signaling cascade, a key mediator of cellular survival, growth, and metabolism, is frequently altered in human cancer. Activating mutations in PIK3CA, which encodes the α-catalytic subunit of PI3K, occur in approximately 30% of breast cancers. These mutations result in constitutive activity of the enzyme and are oncogenic, but it is not known whether they are sufficient to induce mammary carcinomas in mice. In the present study, we show that the expression of mutant PIK3CA H1047R in the luminal mammary epithelium evokes heterogeneous tumors that express luminal and basal markers and are positive for the estrogen receptor. Our results suggest that the PIK3CA H1047R oncogene targets a multipotent progenitor cell and, furthermore, show that this model recapitulates features of human breast tumors with PIK3CA H1047R. Cancer Res; 71(13); 4344–51. ©2011 AACR.