Oncology
Abstract
The long plasma half-life of IgG, while allowing for enhanced tumor uptake of tumor-targeted IgG conjugates, also results in increased background activity and normal-tissue toxicity. Therefore, successful therapeutic uses of conjugated antibodies have been limited to the highly sensitive and readily accessible hematopoietic tumors. We report a therapeutic strategy to beneficially alter the pharmacokinetics of IgG antibodies via pharmacological inhibition of the neonatal Fc receptor (FcRn) using high-dose IgG therapy. IgG-treated mice displayed enhanced blood and whole-body clearance of radioactivity, resulting in better tumor-to-blood image contrast and protection of normal tissue from radiation. Tumor uptake and the resultant therapeutic response was unaltered. Furthermore, we demonstrated the use of this approach for imaging of tumors in humans and discuss its potential applications in cancer imaging and therapy. The ability to reduce the serum persistence of conjugated IgG antibodies after their infusion can enhance their therapeutic index, resulting in improved therapeutic and diagnostic efficacy.
Authors
Jaspreet Singh Jaggi, Jorge A. Carrasquillo, Surya V. Seshan, Pat Zanzonico, Erik Henke, Andrew Nagel, Jazmin Schwartz, Brad Beattie, Barry J. Kappel, Debjit Chattopadhyay, Jing Xiao, George Sgouros, Steven M. Larson, David A. Scheinberg
Abstract
We hypothesized that overexpression of PDGF-BB in colorectal cancer (CRC) and pancreatic cancer cells would result in increased pericyte coverage of ECs in vivo, rendering the tumor vasculature more resistant to antiangiogenic therapy. We stably transfected the cDNA for the PDGF-B into HT-29 human CRC and FG human pancreatic cancer cells. Surprisingly, when HT-29 or FG parental and transfected cells were injected into mice (subcutaneously and orthotopically), we observed marked inhibition of tumor growth in the PDGF-BB–overexpressing clones. In the PDGF-BB–overexpressing tumors, we observed an increase in pericyte coverage of ECs. Treatment of PDGF-BB–overexpressing tumors with imatinib mesylate (PDGFR inhibitor) resulted in increased growth and decreased total pericyte content compared with those in untreated PDGF-BB–overexpressing tumors. In vitro studies demonstrated the ability of VSMCs to inhibit EC proliferation by approximately 50%. These data show that increasing the pericyte content of the tumor microenvironment inhibits the growth of angiogenesis-dependent tumors. Single-agent therapy targeting PDGF receptor must be used with caution in tumors when PDGFR is not the target on the tumor cell itself.
Authors
Marya F. McCarty, Ray J. Somcio, Oliver Stoeltzing, Jane Wey, Fan Fan, Wenbiao Liu, Corazon Bucana, Lee M. Ellis
Abstract
Lymphodepletion with total body irradiation (TBI) increases the efficacy of adoptively transferred tumor-specific CD8+ T cells by depleting inhibitory lymphocytes and increasing homeostatic cytokine levels. We found that TBI augmented the function of adoptively transferred CD8+ T cells in mice genetically deficient in all lymphocytes, indicating the existence of another TBI mechanism of action. Additional investigation revealed commensal gut microflora in the mesenteric lymph nodes and elevated LPS levels in the sera of irradiated mice. These findings correlated with increased dendritic cell activation and heightened levels of systemic inflammatory cytokines. Reduction of host microflora using antibiotics, neutralization of serum LPS using polymyxin B, or removal of LPS signaling components using mice genetically deficient in CD14 and TLR4 reduced the beneficial effects of TBI on tumor regression. Conversely, administration of microbial ligand–containing serum or ultrapure LPS from irradiated animals to nonirradiated antibody-lymphodepleted mice enhanced CD8+ T cell activation and improved tumor regression. Administration of ultrapure LPS to irradiated animals further enhanced the number and function of the adoptively transferred cells, leading to long-term cure of mice with large B16F10 tumors and enhanced autoimmune vitiligo. Thus, disruption of the homeostatic balance between the host and microbes can enhance cell-based tumor immunotherapy.
Authors
Chrystal M. Paulos, Claudia Wrzesinski, Andrew Kaiser,, Christian S. Hinrichs, Marcello Chieppa, Lydie Cassard, Douglas C. Palmer, Andrea Boni, Pawel Muranski, Zhiya Yu, Luca Gattinoni, Paul A. Antony, Steven A. Rosenberg, Nicholas P. Restifo
Abstract
Tumor radioresponsiveness depends on endothelial cell death, which leads in turn to tumor hypoxia. Radiation-induced hypoxia was recently shown to trigger tumor radioresistance by activating angiogenesis through hypoxia-inducible factor 1–regulated (HIF-1–regulated) cytokines. We show here that combining targeted radioiodide therapy with angiogenic inhibitors, such as canstatin, enhances direct tumor cell apoptosis, thereby overcoming radio-induced HIF-1–dependent tumor survival pathways in vitro and in vivo. We found that following dual therapy, HIF-1α increases the activity of the canstatin-induced αvβ5 signaling tumor apoptotic pathway and concomitantly abrogates mitotic checkpoint and tetraploidy triggered by radiation. Apoptosis in conjunction with mitotic catastrophe leads to lethal tumor damage. We discovered that HIF-1 displays a radiosensitizing activity that is highly dependent on treatment modalities by regulating key apoptotic molecular pathways. Our findings therefore support a crucial role for angiogenesis inhibitors in shifting the fate of radiation-induced HIF-1α activity from hypoxia-induced tumor radioresistance to hypoxia-induced tumor apoptosis. This study provides a basis for developing new biology-based clinically relevant strategies to improve the efficacy of radiation oncology, using HIF-1 as an ally for cancer therapy.
Authors
Claire Magnon, Paule Opolon, Marcel Ricard, Elisabeth Connault, Patrice Ardouin, Ariane Galaup, Didier Métivier, Jean-Michel Bidart, Stéphane Germain, Michel Perricaudet, Martin Schlumberger
Abstract
Granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances protection against tumors and infections, but GM-CSF–deficient mice develop inflammatory disease. Here we show that GM-CSF is required for the expression of milk fat globule EGF 8 (MFG-E8) in antigen-presenting cells, and that MFG-E8–mediated uptake of apoptotic cells is a key determinant of GM-CSF–triggered tolerance and immunity. Upon exposure to apoptotic cells, GM-CSF–deficient antigen-presenting cells (APCs) produce an altered cytokine profile that results in decreased Tregs and increased Th1 cells, whereas concurrent ablation of IFN-γ promotes Th17 cells. In wild-type mice, MFG-E8 attenuates the vaccination activity of GM-CSF–secreting tumor cells through Treg induction, whereas a dominant-negative MFG-E8 mutant potentiates GM-CSF–stimulated tumor destruction through Treg inhibition. These findings clarify the immunoregulatory effects of apoptotic cells and suggest new therapeutic strategies to modulate CD4+ T cell subsets in cancer and autoimmunity.
Authors
Masahisa Jinushi, Yukoh Nakazaki, Michael Dougan, Daniel R. Carrasco, Martin Mihm, Glenn Dranoff
Abstract
We have developed an integrated, multidisciplinary methodology, termed systems pathology, to generate highly accurate predictive tools for complex diseases, using prostate cancer for the prototype. To predict the recurrence of prostate cancer following radical prostatectomy, defined by rising serum prostate-specific antigen (PSA), we used machine learning to develop a model based on clinicopathologic variables, histologic tumor characteristics, and cell type–specific quantification of biomarkers. The initial study was based on a cohort of 323 patients and identified that high levels of the androgen receptor, as detected by immunohistochemistry, were associated with a reduced time to PSA recurrence. The model predicted recurrence with high accuracy, as indicated by a concordance index in the validation set of 0.82, sensitivity of 96%, and specificity of 72%. We extended this approach, employing quantitative multiplex immunofluorescence, on an expanded cohort of 682 patients. The model again predicted PSA recurrence with high accuracy, concordance index being 0.77, sensitivity of 77% and specificity of 72%. The androgen receptor was selected, along with 5 clinicopathologic features (seminal vesicle invasion, biopsy Gleason score, extracapsular extension, preoperative PSA, and dominant prostatectomy Gleason grade) as well as 2 histologic features (texture of epithelial nuclei and cytoplasm in tumor only regions). This robust platform has broad applications in patient diagnosis, treatment management, and prognostication.
Authors
Carlos Cordon-Cardo, Angeliki Kotsianti, David A. Verbel, Mikhail Teverovskiy, Paola Capodieci, Stefan Hamann, Yusuf Jeffers, Mark Clayton, Faysal Elkhettabi, Faisal M. Khan, Marina Sapir, Valentina Bayer-Zubek, Yevgen Vengrenyuk, Stephen Fogarsi, Olivier Saidi, Victor E. Reuter, Howard I. Scher, Michael W. Kattan, Fernando J. Bianco Jr., Thomas M. Wheeler, Gustavo E. Ayala, Peter T. Scardino, Michael J. Donovan
Abstract
Although a causal role of genetic alterations in human cancer is well established, it is still unclear whether dietary fat can modulate cancer risk in a predisposed population. Epidemiological studies suggest that diets rich in omega-3 polyunsaturated fatty acids reduce cancer incidence. To determine the influence of fatty acids on prostate cancer risk in animals with a defined genetic lesion, we used prostate-specific Pten-knockout mice, an immune-competent, orthotopic prostate cancer model, and diets with defined polyunsaturated fatty acid levels. We found that omega-3 fatty acids reduced prostate tumor growth, slowed histopathological progression, and increased survival, whereas omega-6 fatty acids had opposite effects. Introducing an omega-3 desaturase, which converts omega-6 to omega-3 fatty acids, into the Pten-knockout mice reduced tumor growth similarly to the omega-3 diet. Tumors from mice on the omega-3 diet had lower proportions of phosphorylated Bad and higher apoptotic indexes compared with those from mice on omega-6 diet. Knockdown of Bad eliminated omega-3–induced cell death, and introduction of exogenous Bad restored the sensitivity to omega-3 fatty acids. Our data suggest that modulation of prostate cancer development by polyunsaturated fatty acids is mediated in part through Bad-dependent apoptosis. This study highlights the importance of gene-diet interactions in prostate cancer.
Authors
Isabelle M. Berquin, Younong Min, Ruping Wu, Jiansheng Wu, Donna Perry, J. Mark Cline, Mike J. Thomas, Todd Thornburg, George Kulik, Adrienne Smith, Iris J. Edwards, Ralph D’Agostino Jr., Hao Zhang, Hong Wu, Jing X. Kang, Yong Q. Chen
Abstract
Retinoic acid receptors (RARs) are members of the nuclear hormone receptor family and regulate the proliferation and differentiation of multiple different cell types, including promyelocytic leukemia cells. Here we describe a biochemical/functional interaction between the Ca2+/calmodulin–dependent protein kinases (CaMKs) and RARs that modulates the differentiation of myeloid leukemia cells. We observe that CaMKIIγ is the CaMK that is predominantly expressed in myeloid cells. CaMKII inhibits RAR transcriptional activity, and this enzyme directly interacts with RAR through a CaMKII LxxLL binding motif. CaMKIIγ phosphorylates RARα both in vitro and in vivo, and this phosphorylation inhibits RARα activity by enhancing its interaction with transcriptional corepressors. In myeloid cell lines, CaMKIIγ localizes to RAR target sites within myeloid gene promoters but dissociates from the promoter upon retinoic acid–induced myeloid cell differentiation. KN62, a pharmacological inhibitor of the CaMKs, enhances the terminal differentiation of myeloid leukemia cell lines, and this is associated with a reduction in activated (autophosphorylated) CaMKII in the terminally differentiating cells. These observations reveal a significant cross-talk between Ca2+ and retinoic acid signaling pathways that regulates the differentiation of myeloid leukemia cells, and they suggest that CaMKIIγ may provide a new therapeutic target for the treatment of certain human myeloid leukemias.
Authors
Jutong Si, LeMoyne Mueller, Steven J. Collins
Abstract
Breast cancers lacking estrogen and progesterone receptor expression and Her2 amplification exhibit distinct gene expression profiles and clinical features, and they comprise the majority of BRCA1-associated tumors. Here we demonstrated that the p53 family member p63 controls a pathway for p73-dependent cisplatin sensitivity specific to these “triple-negative” tumors. In vivo, ΔNp63 and TAp73 isoforms were coexpressed exclusively within a subset of triple-negative primary breast cancers that commonly exhibited mutational inactivation of p53. The ΔNp63α isoform promoted survival of breast cancer cells by binding TAp73 and thereby inhibiting its proapoptotic activity. Consequently, inhibition of p63 by RNA interference led to TAp73-dependent induction of proapoptotic Bcl-2 family members and apoptosis. Breast cancer cells expressing ΔNp63α and TAp73 exhibited cisplatin sensitivity that was uniquely dependent on TAp73. Thus, in response to treatment with cisplatin, but not other chemotherapeutic agents, TAp73 underwent c-Abl–dependent phosphorylation, which promoted dissociation of the ΔNp63α/TAp73 protein complex, TAp73-dependent transcription of proapoptotic Bcl-2 family members, and apoptosis. These findings define p63 as a survival factor in a subset of breast cancers; furthermore, they provide what we believe to be a novel mechanism for cisplatin sensitivity in these triple-negative cancers, and they suggest that such cancers may share the cisplatin sensitivity of BRCA1-associated tumors.
Authors
Chee-Onn Leong, Nick Vidnovic, Maurice Phillip DeYoung, Dennis Sgroi, Leif W. Ellisen
Abstract
The Fanconi anemia (FA) pathway maintains genomic stability in replicating cells. Some sporadic breast, ovarian, pancreatic, and hematological tumors are deficient in FA pathway function, resulting in sensitivity to DNA-damaging agents. FA pathway dysfunction in these tumors may result in hyperdependence on alternative DNA repair pathways that could be targeted as a treatment strategy. We used a high-throughput siRNA screening approach that identified ataxia telangiectasia mutated (ATM) as a critical kinase for FA pathway–deficient human fibroblasts. Human fibroblasts and murine embryonic fibroblasts deficient for the FA pathway were observed to have constitutive ATM activation and Fancg–/–Atm–/– mice were found to be nonviable. Abrogation of ATM function in FA pathway–deficient cells resulted in DNA breakage, cell cycle arrest, and apoptotic cell death. Moreover, Fanconi anemia complementation group G– (FANCG-) and FANCC-deficient pancreatic tumor lines were more sensitive to the ATM inhibitor KU-55933 than isogenic corrected lines. These data suggest that ATM and FA genes function in parallel and compensatory roles to maintain genomic integrity and cell viability. Pharmaceutical inhibition of ATM may have a role in the treatment of FA pathway–deficient human cancers.
Authors
Richard D. Kennedy, Clark C. Chen, Patricia Stuckert, Elyse M. Archila, Michelle A. De la Vega, Lisa A. Moreau, Akiko Shimamura, Alan D. D’Andrea
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)