New Paradigm In Cancer Treatment Research Articles

Abstract 1722: KRAS, BRAF, BRCA1 and EGFR mutation-specific panels using hydrogel-based 3D in vitro tumor models

Abstract Mutation-targeting therapies have become a transformative technology and in many ways a new paradigm for cancer treatment for patients. The early development of Erlotinib for non-small cell lung cancer paved the way for EGFR treatment, irrespective of tumor indication subtype. And the more recent launch of Sotorasib for KRASG12C mutation has marked a turning point for the once undruggable mutation. The advent of gene specific-treatments requires a reconfiguration of preclinical models which more effectively represent the said mutation in populations of diverse backgrounds and tumor indications. 3D models which have the ability to recreate the key hallmarks of cancer - such as growth, invasion, immune infiltration and suppression, stromal transformation, drug diffusion, as well as gene mutational signatures - are of exceptional interest to drive rapid and scalable compound efficacy screening. Here, we developed four 3D in vitro tumor panels carrying mutations in one of the following genes - KRAS, EGFR, BRCA1, and BRAF - as well as wildtype models for comparison. The tumors were grown in a hydrogel matrix in 96-well plates with stromal fibroblasts and screened with the standard of care (e.g. Sotorasib for KRASG12C, Erlotinib for EGFRmut, the PARP inhibitor Olaparib for BRCAmut, and Vemurafenib for BRAFV600E) and other known therapeutic compounds that target their respective mutations. The utility of a 3D hydrogel matrix and fibroblasts in the panels’ models were key in recreating the stromal compartment of the tumor microenvironment. Endpoints were determined within four days of treatment, including tumor size reduction and tumor killing, via high-content image analysis. The Panels’ robustness as demonstrated by the reproducible results in independent experiments suggests they can be utilized at in vitro pharmacology stages and earlier in Hit and Lead finding screens. Citation Format: Bin Xue, Julia Schüler, Christopher Harrod, Zoji Bomya, Kolin C. Hribar. KRAS, BRAF, BRCA1 and EGFR mutation-specific panels using hydrogel-based 3D in vitro tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1722.

Immunogenic cell death in cancer immunotherapy

Cancer immunotherapy has been acknowledged as a new paradigm for cancer treatment, with notable therapeutic effects on certain cancer types. Despite their significant potential, clinical studies over the past decade have revealed that cancer immunotherapy has low response rates in the majority of solid tumors. One of the key causes for poor responses is known to be the relatively low immunogenicity of solid tumors. Because most solid tumors are immune desert 'cold tumors' with antitumor immunity blocked from the onset of innate immunity, combination therapies that combine validated T-based therapies with approaches that can increase tumor-immunogenicity are being considered as relevant therapeutic options. This review paper focuses on immunogenic cell death (ICD) as a way of enhancing immunogenicity in tumor tissues. We will thoroughly review how ICDs such as necroptosis, pyroptosis, and ferroptosis can improve anti-tumor immunity and outline clinical trials targeting ICD. Finally, we will discuss the potential of ICD inducers as an adjuvant for cancer immunotherapy.

Abstract P6-11-11: Breast cancer stem cell marker, CD24 regulates metabolic reprogramming in triple negative breast cancer

Abstract Breast cancer stem cell (BCSC) is a subset of cancer cells that can dictate the tumor initiation, metastatic progression, and therapeutic resistance in BC. The eradication of this unusual population is emerging as a new paradigm in cancer treatment. Molecularly, CD24 negativity in conjunction with high expression of CD44 is considered a hallmark for the BCSCs. While extensive studies have been performed to delineate the role of CD44 in BCSCs, the regulation of CD24 and its functional role have not been fully understood. In this study, we investigated the regulatory mechanisms responsible for low CD24 expression in BCSCs and their functional relevance in BCSCs. Analysis of DNA from tumor tissues and blood from BC patients as well as BCSCs sorted from BC cell lines suggest that CD24 is epigenetically regulated via DNMT-1/HDAC1-dependent increased methylation of CpG islands in the CD24 proximal promoter region. To understand the role of CD24 in triple-negative BC (TNBC), an aggressive subgroup of BC, we knocked down (CD24-KD) and overexpressed (CD24-OE) CD24 in metastatic TNBC cells. While CD24-KD resulted in increased proliferation and stemness, CD24-OE diminished the proliferative and stem-like potential. To further identify the signaling cascade underpinning these effects, we performed phospho-proteome analysis using Reverse Phase Protein Array (RPPA). Remarkably, we observed an enhanced activation of AMPK and NF-kB signaling cascades, and reduced PDGFRβ signaling upon depletion of CD24. As signaling cascades are intricately linked to cellular metabolism, we performed a metabolomic analysis of CD24-KD and CD24-OE cells. Our comprehensive analysis revealed heightened activation of mitochondrial fatty acid β-oxidation (FAO) in CD24-KD and increased glutamine metabolism in CD24-OE cells. In coherence with these findings, we observed significant regulation of genes related to fatty acid metabolism in the TNBC patient cohort expressing low levels of CD24. Consistently, the CD24-KD cells demonstrated increased sensitivity towards FAO inhibitors while CD24-OE cells were more sensitive to glutamine metabolism inhibitors. In vivo studies to further understand the translational significance of this metabolic axis is underway. Taken together, our study demonstrates, for the first time, that CD24 presents a novel metabolic vulnerability that can target BCSCs to gain a therapeutic advantage in the treatment of drug-resistant TNBC patients. Citation Format: Divya Murthy, Debasmita Dutta, Sukjin Yang, Junhyoung Park, Benny Kaipparettu. Breast cancer stem cell marker, CD24 regulates metabolic reprogramming in triple negative breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-11-11.

Hexokinase 2: The preferential target of trehalose-6-phosphate over hexokinase 1.

Cancer-related metabolic features are in part maintained by hexokinase 2 upregulation, which leads to high levels of glucose-6-phosphate (G6P) and is needed to provide energy and biomass to support rapid proliferation. Using a humanized model of the yeast Saccharomyces cerevisiae, we explored how human hexokinase 2 (HK2) behaves under different nutritional conditions. At high glucose levels, yeast presents aerobic glycolysis through a regulatory mechanism known as catabolic repression, which exerts a metabolic adaptation like the Warburg effect. At high glucose concentrations, HK2 did not translocate into the nucleus and was not able to shift the metabolism toward a highly glycolytic state, in contrast to the effect of yeast hexokinase 2 (Hxk2), which is a crucial protein for the control of aerobic glycolysis in S. cerevisiae. During the stationary phase, when glucose is exhausted, Hxk2 is shuttled out of the nucleus, ceasing catabolic repression. Cells harvested at this condition display low glucose consumption rates. However, glucose-starved cells expressing HK2 had an increased capacity to consume glucose. In those cells, HK2 localized to mitochondria, becoming insensitive to G6P inhibition. We also found that the sugar trehalose-6-phosphate (T6P) is a human HK2 inhibitor, like yeast Hxk2, but was not able to inhibit human HK1, the isoform that is ubiquitously expressed in almost all mammalian tissues. In contrast to G6P, T6P inhibited HK2 even when HK2 was associated with mitochondria. The binding of HK2 to mitochondria is crucial for cancer survival and proliferation. T6P was able to reduce the cell viability of tumor cells, although its toxicity was not impressive. This was expected as cell absorption of phosphorylated sugars is low, which might be counteracted using nanotechnology. Altogether, these data suggest that T6P may offer a new paradigm for cancer treatment based on specific inhibition of HK2.

Abstract 2750: Bioluminescent bioassays for the discovery and development of molecular and cellular T-cell redirecting cancer therapy

Abstract Redirected T cell therapies represent a new paradigm for cancer treatment. Two main approaches for T-cell-based therapies involve molecular T cell redirection by CD3 bispecific molecules such as bispecific T-cell engagers (BiTE) and cellular T cell redirection by genetic modification of T cells with chimeric antigen receptors (CAR) or transgenic T cell receptors (TCR). BiTEs redirect the cytotoxic activity of endogenous polyclonal T cells by simultaneously engaging CD3 on T cells and tumor antigens on target cells. Hitherto, BiTE potency studies have relied on primary cells, which measure target cell killing through redirected T cell cytotoxicity (RTCC) or cytokine release. However, these primary cell-based assays suffer from high donor-to-donor variability, as well as lengthy and hard to implement protocols. We have recently developed a new NanoBiT-based assay platform-based RTCC assay and cytokine immunoassays that are simple, sensitive and can quantitatively measure the potency of CD3 bispecific antibodies or BiTEs and similar biologics that induce T Cell-dependent target cell killing and cytokine production. In this assay, preactivated, Thaw-and-Use cytotoxic T cells and target cells stably expressing HaloTag-HiBiT are co-incubated with a BiTE, which results in lysis of the target cells and release of HiBiT proteins. These HiBiT proteins then bind to LgBiT in the detection reagent and form functional NanoLuc Luciferase to generate luminescence. The assay is homogenous, highly sensitive, and has a robust assay window. Furthermore, BiTE-induced cytokine production (e.g IL-2 and IFN gamma) from the activated cytotoxic T cells can be quantitatively measured in the homogenous NanoBiT Immunoassays. Use of CAR-T has demonstrated promising results in treating leukemia, while the development of TCR-engineered T cells that can recognize intracellular tumor antigens, is still in early stages. To facilitate the screening and characterization of new transgenic TCRs, we used CRISPR/Cas9 to develop two TCRab-null reporter T cell lines, which are CD4+ or CD8+. Reintroduction of peptide-specific TCR a and b chains into TCRab-null reporter T cell lines results in peptide-dependent TCR activation and luciferase reporter expression. The select expression of CD4 or CD8 in the TCRab-null reporter T cell lines can enable the development of transgenic TCRs for both MHCI- and MHCII-restricted tumor antigen targets. Together, these bioluminescent bioassays represent a new set of tools for the discovery and development of T cell-based immunotherapies. Citation Format: Julia Gilden, Jamison Grailer, Michael Slater, Pete Stecha, Jim Hartnett, Dan Lazar, Gopal Krishnan, Frank Fan, Mei Cong, Zhijie Jey Cheng. Bioluminescent bioassays for the discovery and development of molecular and cellular T-cell redirecting cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2750.

Alpinetin: a Dietary Flavonoid with Diverse Anticancer Effects.

Cancer is a global burden and mechanistically complex disease with a plethora of genetic, physiological, metabolic, and environmental alterations. The development of dietary nutraceuticals into cancer chemotherapeutics has emerged as a new paradigm in cancer treatment. Alpinetin (ALPI) is a novel flavonoid component of multiple edible and medicinal plants and possesses a wide range of biological and pharmacological activities including antibacterial, anti-hemostatic, anti-oxidative, anti-hepatotoxic, stomachic, immunosuppressive, and anti-inflammatory. Recently, ALPI has been reported as a bioactive dietary nutraceutical with promising anticancer activity in various human cancers through multiple mechanisms. The purpose of this review is to compile the data on natural sources of ALPI, and its anticancer activity including cellular targets and anticancer mechanism in various human cancers. Moreover, this review will set the stage for further design and conduct pre-clinical and clinical trials to develop ALPI into a lead structure for oncological therapy.

Local Destruction of Tumors for Systemic Immunoresponse: Engineering Antigen-Capturing Nanoparticles as Stimulus-Responsive Immunoadjuvants.

Immunotherapy has established a new paradigm for cancer treatment and made many breakthroughs in clinical practice. However, the rarity of immune response suggests that additional intervention is necessary. In recent years, it has been reported that local tumor destruction (LTD) can cause cancer cell death and induce an immunologic response. Thus, the combination of immunotherapy and LTD methods will be a promising approach to improve immune efficiency for cancer treatment. Herein, a nanobiotechnology platform to achieve high-precision LTD for systemic cancer immunotherapy has been successfully constructed. Possessing radio-sensitizing and photothermal properties, the engineered immunoadjuvant-loaded nanoplatform, which could precisely induce radiotherapy (RT)/photothermal therapy (PTT) to eliminate local tumor and meanwhile lead to the release of tumor-derived protein antigens (TDPAs), has been facilely fabricated by commercialized SPG membrane emulsification technology. Further on, the TDPAs could be captured and form personal nanovaccines in situ to serve as both reservoirs of antigen and carriers of immunoadjuvant, which can effectively improve the immune response. The investigations suggest that the combination of RT/PTT and improved immunotherapy using adjuvant-encapsulated antigen-capturing nanoparticles holds tremendous promise in cancer treatments.

Evolution of Radiological Treatment Response Assessments for Cancer Immunotherapy: From iRECIST to Radiomics and Artificial Intelligence.

Immunotherapy has revolutionized and opened a new paradigm for cancer treatment. In the era of immunotherapy and molecular targeted therapy, precision medicine has gained emphasis, and an early response assessment is a key element of this approach. Treatment response assessment for immunotherapy is challenging for radiologists because of the rapid development of immunotherapeutic agents, from immune checkpoint inhibitors to chimeric antigen receptor-T cells, with which many radiologists may not be familiar, and the atypical responses to therapy, such as pseudoprogression and hyperprogression. Therefore, new response assessment methods such as immune response assessment, functional/molecular imaging biomarkers, and artificial intelligence (including radiomics and machine learning approaches) have been developed and investigated. Radiologists should be aware of recent trends in immunotherapy development and new response assessment methods.

Harnessing the combined potential of cancer immunotherapy and nanomedicine: A new paradigm in cancer treatment

Cancer immunotherapy has recently emerged as a rising star due to its ability to activate patients' immune systems to fight tumors and prevent relapse. Conversely, the interest in cancer nanomedicine has seemingly waned due to its lackluster clinical translation. Despite being hailed as a game-changer in oncology, cancer immunotherapy still faces numerous challenges. Combining both entities together has thus been one among several solutions proposed to circumvent these challenges. This solution has since gained traction and has also led to a renaissance of cancer nanomedicine. While most combinations are currently experimental at best, some have progressed on to clinical trials. This review thus seeks to examine the advantages and disadvantages of integrating both modalities as a cancer treatment. The opportunities, challenges and future directions of this emerging field will also be explored with the hope that such a combination will lead to a paradigm shift in cancer treatments.

Glioblastoma Therapy: Rationale for a Mesenchymal Stem Cell-based Vehicle to Carry Recombinant Viruses.

Evasion of growth suppression is among the prominent hallmarks of cancer. Phosphatase and tensin homolog (PTEN) and p53 tumor-suppressive pathways are compromised in most human cancers, including glioblastoma (GB). Hence, these signaling pathways are an ideal point of focus for novel cancer therapeutics. Recombinant viruses can selectivity kill cancer cells and carry therapeutic genes to tumors. Specifically, oncolytic viruses (OV) have been successfully employed for gene delivery in GB animal models and showed potential to neutralize immunosuppression at the tumor site. However, the associated systemic immunogenicity, inefficient transduction of GB cells, and inadequate distribution to metastatic tumors have been the major bottlenecks in clinical studies. Mesenchymal stem cells (MSCs), with tumor-tropic properties and immune privilege, can improve OVs targeting. Remarkably, combining the two approaches can address their individual issues.Herein, we summarize findings to advocate the reactivation of tumor suppressors p53 and PTEN in GB treatment and use MSCs as a "Trojan horse" to carry oncolytic viral cargo to disseminated tumor beds. The integration of MSCs and OVs can emerge as the new paradigm in cancer treatment.

Abstract 334: Novel bioluminescent bioassays for the discovery and development of molecular and cellular T cell-redirecting cancer therapy

Abstract Redirected T cell therapies represent a new paradigm for cancer treatment. Two main approaches for T-cell-based therapies involve molecular T cell redirection by CD3 bispecific molecules such as bispecific T-cell engagers (BiTE) and cellular T cell redirection by genetic modification of T cells with chimeric antigen receptors (CAR) or transgenic T cell receptors (TCR). BiTEs redirect the cytotoxic activity of endogenous polyclonal T cells by simultaneously engaging CD3 on T cells and tumor antigens on target cells. Hitherto, BiTE potency studies have relied on primary cells, which measure target cell killing through redirected T cell cytotoxicity (RTCC) or cytokine release. However, these primary cell-based assays suffer from high donor-to-donor variability, as well as lengthy and hard to implement protocols. We have recently developed a new RTCC assay and cytokine immunoassays that are simple, sensitive and can quantitatively measure the potency of BiTEs and similar biologics. In this assay, preactivated, Thaw-and-Use cytotoxic T cells and target cells stably expressing HaloTag-HiBiT are co-incubated with a BiTE, which results in lysis of the target cells and release of HiBiT proteins. These HiBiT proteins then bind to LgBiT in the detection reagent and form functional NanoLuc Luciferase to generate luminescence. The assay is homogenous, highly sensitive, and has a robust assay window. Furthermore, BiTE-induced cytokine production (e.g IL-2 and IFN-γ) from the activated cytotoxic T cells can be quantitatively measured in the homogenous NanoBiT Immunoassays. Use of CAR-T has demonstrated promising results in treating leukemia, while the development of TCR-engineered T cells that can recognize intracellular tumor antigens, is still in early stages. To facilitate the screening and characterization of new transgenic TCRs, we used CRISPR/Cas9 to develop two TCRαβ-null reporter T cell lines, which are CD4+ or CD8+. Reintroduction of peptide-specific TCR α and β chains into TCRαβ-null reporter T cell lines results in peptide-dependent TCR activation and luciferase reporter expression. The select expression of CD4 or CD8 in the TCRαβ-null reporter T cell lines can enable the development of transgenic TCRs for both MHCI- and MHCII-restricted tumor antigen targets. Together, these bioluminescent bioassays represent a new set of tools for the discovery and development of T cell-based immunotherapies. Citation Format: Julia Gilden, Jamison Grailer, Michael Slater, Pete Stecha, Jim Hartnett, Dan Lazar, Vanessa Ott, Frank Fan, Mei Cong, Zhijie Jey Cheng. Novel bioluminescent bioassays for the discovery and development of molecular and cellular T cell-redirecting cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 334.

Complex interaction of adipokines in breast cancer and anti-tumour immunity; a new paradigm for cancer treatment

Obesity and its related complications have been the pressing disease pandemic affecting the developed world. It is well-established that the direct consequence of obesity in the cardiovascular system resulting in many diseases. However, its implications in carcinogenesis, cancer treatment and one’s anti-tumour immunity are gradually unfolding. To understand how fat cells can affect these, one needs to explore how the fat cell affects epithelial and immune cells. To this end, we explore the way how the adipocytes, via its production of adipokines, influence these cells, resulting in early epithelial cell transformation into cancer cells and influencing anti-tumour immunity once the cancer is established. In order to simplify our discussion, we focus this review on breast cancer. We propose that to have an effective therapy for cancer treatment, we need to intervene at the adipokine interaction with epithelial cells, cancer cells, and immune cells. In this review we also decipher the potential therapeutic targets in controlling carcinogenesis and disease progression.

EDC3 phosphorylation regulates growth and invasion through controlling P-body formation and dynamics.

Regulation of mRNA stability and translation plays a critical role in determining protein abundance within cells. Processing bodies (P-bodies) are critical regulators of these processes. Here, we report that the Pim1 and 3 protein kinases bind to the P-body protein enhancer of mRNA decapping 3 (EDC3) and phosphorylate EDC3 on serine (S)161, thereby modifying P-body assembly. EDC3 phosphorylation is highly elevated in many tumor types, is reduced upon treatment of cells with kinase inhibitors, and blocks the localization of EDC3 to P-bodies. Prostate cancer cells harboring an EDC3 S161A mutation show markedly decreased growth, migration, and invasion in tissue culture and in xenograft models. Consistent with these phenotypic changes, the expression of integrin β1 and α6 mRNA and protein is reduced in these mutated cells. These results demonstrate that EDC3 phosphorylation regulates multiple cancer-relevant functions and suggest that modulation of P-body activity may represent a new paradigm for cancer treatment.

Changing the landscape of tumor immunology: novel tools to examine T cell specificity.

Immunotherapy has established itself as a stalwart arm in patient care and with precision medicine forms the new paradigm in cancer treatment. T cells are an important group of immune cells capable of potent cancer immune surveillance and immunity. The advent of bioinformatics, particularly more recent advances incorporating algorithms employing machine learning, provide a seemingly limitless ability for T cell analysis and hypothesis generation. Such endeavors have become indispensable to research efforts accelerating and evolving to such an extent that there exists an appreciable gap between knowledge and proof of function and application. Exciting new technologies such as DNA barcoding, cytometry by time-of-flight (CyTOF), and peptide-exchangeable pHLA multimers inclusive of rare and difficult HLA alleles offer high-throughput cell-by-cell analytical capabilities. These outstanding recent contributions to T cell research will help close this gap and potentially bring practical benefit to patients.

A new aspect of an old friend: the beneficial effect of metformin on anti-tumor immunity

T-cell-based cancer immunotherapies, such as immune checkpoint blockers (ICBs) and chimeric antigen receptor (CAR)-T-cells, have significant anti-tumor effects against certain types of cancer, providing a new paradigm for cancer treatment. However, the activity of tumor infiltrating T-cells (TILs) can be effectively neutralized in the tumor microenvironment (TME) of most solid tumors, rich in various immunosuppressive factors and cells. Therefore, to improve the clinical outcomes of established T-cell-based immunotherapy, adjuvants that can comprehensively relieve multiple immunosuppressive mechanisms of TME are needed. In this regard, recent studies have revealed that metformin has several beneficial effects on anti-tumor immunity. In this mini-review, we understand the immunosuppressive properties of TME and how metformin comprehensively enhances anti-tumor immunity. Finally, we will discuss this old friend’s potential as an adjuvant for cancer immunotherapy.

Abstract 2179: Novel bioluminescent bioassays for the discovery and development of molecular and cellular T cell redirecting cancer therapy

Abstract Redirected T cell therapies represent a new paradigm for cancer treatment. Two main approaches for T-cell-based therapies involve molecular T cell redirection by CD3 bispecific molecules such as bispecific T-cell engagers (BiTE) and cellular T cell redirection by genetic modification of T cells with chimeric antigen receptors (CAR) or transgenic T cell receptors (TCR). BiTEs redirect the cytotoxic activity of endogenous polyclonal T cells by simultaneously engaging CD3 on T cells and tumor antigens on target cells. Hitherto, BiTE potency studies have relied on primary cells, which measure target cell killing through redirected T cell cytotoxicity (RTCC) or cytokine release. However, these primary cell-based assays suffer from high donor-to-donor variability, as well as lengthy and hard to implement protocols. We have recently developed a new RTCC assay and cytokine immunoassays that are simple, sensitive and can quantitatively measure the potency of BiTEs and similar biologics. In this assay, preactivated, Thaw-and-Use cytotoxic T cells and target cells stably expressing HaloTag-HiBiT are co-incubated with a BiTE, which results in lysis of the target cells and release of HiBiT proteins. These HiBiT proteins then bind to LgBiT in the detection reagent and form functional NanoLuc Luciferase to generate luminescence. The assay is homogenous, highly sensitive, and has a robust assay window. Furthermore, BiTE-induced cytokine production (e.g IL-2 and IFN-γ) from the activated cytotoxic T cells can be quantitatively measured in the homogenous NanoBiT Immunoassays. Use of CAR-T has demonstrated promising results in treating leukemia, while the development of TCR-engineered T cells that can recognize intracellular tumor antigens, is still in early stages. To facilitate the screening and characterization of new transgenic TCRs, we used CRISPR/Cas9 to develop two TCRαβ-null reporter T cell lines, which are CD4+ or CD8+. Reintroduction of peptide-specific TCR α and β chains into TCRαβ-null reporter T cell lines results in peptide-dependent TCR activation and luciferase reporter expression. The select expression of CD4 or CD8 in the TCRαβ-null reporter T cell lines can enable the development of transgenic TCRs for both MHCI- and MHCII-restricted tumor antigen targets. Together, these bioluminescent bioassays represent a new set of tools for the discovery and development of T cell-based immunotherapies. Citation Format: Julia K. Gilden, Jamison Grailer, Michael Slater, Pete Stecha, Jim Hartnett, Dan Lazar, Frank Fan, Mei Cong, Zhijie Jey Cheng. Novel bioluminescent bioassays for the discovery and development of molecular and cellular T cell redirecting cancer therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2179.

Abstract 5307: The impact of image analysis and multiplex hybridization on PD-L1 diagnostic case triage

Abstract Introduction: Immune checkpoint blockade therapy is a new paradigm in cancer treatment with durable tumor regression and prolonged stabilization of disease in patients with advanced cancers, including non-small cell lung cancer (NSCLC). However, clinical assessment using immunohistochemistry (IHC) remains complex and ambiguous. Methods: PD-L1 IHC staining was performed as a routine clinical reflex test on 802 NSCLC cases over an 18 month period using an automated staining system with PD-L1 clone SP263. PD-L1 expression was assessed using image analysis (IA) by 2 individuals and concordance was evaluated between the recorded manual clinical score and the digitally generated score. Additionally, a subset of 330 samples, representing cases with either varying PD-L1 expression or difficulty in assessment, were stained by multiplex immunofluorescence. Sensitivity and specificity was compared between manual assessments of both chromogenic and multiplex IHC. Results: PD-L1 expression by IA showed significant concordance (R²=0.8248) to manual assessment. Sensitivity and specificity was 86.8% and 91.4%, respectively. Discordant cases were mainly due to spurious or poor staining quality, difficult classification by IA and overabundant macrophages and a low IA detection threshold. Evaluation of IA scores 10-49% and >70% revealed 96.8% concordance to manual assessment. Multiplex assessment enabled PD-L1+/CD68+ macrophages to be readily identified within PD-L1+/CK+ or PD-L1-/CK+ tumor nests. Manual assessment of multiplex vs. chromogenic IHC was highly concordant, with a sensitivity and specificity respectively of 97.8% and 91.8%. Conclusions: Deployment of IA in routine PD-L1 IHC assessment of NSCLC represents a beneficial time saving process and could aid case triage saving >50% of pathologist review time. However cases close to diagnostic thresholds still require a more comprehensive pathological evaluation. Multiplex IHC provides a higher level of confidence in PD-L1 assessment and could be offered for challenging cases by centers with access to appropriate expertise and specialist equipment. Citation Format: Matthew P. Humphries, Victoria Bingham, Fatima Abdullahi Sidi, Stephanie G. Craig, Stephen McQuaid, Jacquline James, Manuel Salto-Tellez. The impact of image analysis and multiplex hybridization on PD-L1 diagnostic case triage [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5307.

Cellular immunotherapy: a clinical state-of-the-art of a new paradigm for cancer treatment.

Cancer immunotherapy has opened a new chapter in Medical Oncology. Many novel therapies are under clinical testing and some have already been approved and implemented in cancer treatment protocols. In particular, cellular immunotherapies take advantage of the antitumor capabilities of the immune system. From dendritic cell-based vaccines to treatments centered on genetically engineered T cells, this form of personalized cancer therapy has taken the field by storm. They commonly share the ex vivo genetic modification of the patient's immune cells to generate or induce tumor antigen-specific immune responses. The latest clinical trials and translational research have shed light on its clinical effectiveness as well as on the mechanisms behind targeting specific antigens or unique tumor alterations. This review gives an overview of the clinical developments in immune cell-based technologies predominantly for solid tumors and on how the latest discoveries are being incorporated within the standard of care.

Abstract C130: Precision oncology decision support within the Gastrointestinal Cancer Center at Dana-Farber Cancer Institute (GI TARGET)

Abstract Precision oncology is fast becoming the new paradigm for cancer treatment. This approach involves molecular profiling of patient tumors and tailoring of a treatment regimen based on the unique combination of targetable alterations identified therein. At Dana-Farber Cancer Institute (DFCI), over 24,000 patient tumors have been sequenced using the NGS platform OncoPanel since 2013. OncoPanel is a comprehensive genomic characterization of a tumor and it can be time-consuming to discern those alterations that are interesting from an academic or research perspective from those that can be leveraged to direct patient care. To address this issue, the GI TARGET (Treatment Assistance Regarding Genomic Evaluation of Tumors) project was initiated to provide decision support for oncologists within the DFCI Gastrointestinal Cancer Center (GCC). GI TARGET is a collaboration between the DFCI GCC, the Brigham & Women’s Hospital (BWH) Center for Advanced Molecular Diagnostics (CAMD), and the DFCI Knowledge Systems Group, developers of the precision medicine clinical trial matching platform MatchMiner. Report generation involves review of OncoPanel data in the context of patient clinical history via one of two workflows; complex genomic cases are reviewed in a weekly Molecular Tumor Board comprised of oncologists, molecular pathologists, a PhD-level Clinical Genomics Scientist, and representatives from the MatchMiner team, while ‘simple’ genomic cases are reviewed by both an oncologist and a PhD-level Clinical Genomics Scientist. Since the launch of the project in January 2018, we have signed out over 1000 GI TARGET reports. We are assessing the utility of these reports using a number of metrics including clinical trial enrollment tracking via MatchMiner, follow-up on recommendations via chart abstraction, and oncologist feedback. The aims of GI TARGET are 1) to reduce the burden of genomic analysis on the treating oncologist by providing expert-led deep review of OncoPanel and exploration of associated therapy/additional patient care considerations, 2) to support clinical trial enrollment by matching the results of somatic testing with ongoing clinical studies, and 3) to provide an example framework for how precision oncology can be incorporated into standard clinical cancer care, which may be helpful to guide efforts in other care settings, particularly in community hospitals where the vast majority (an estimated 80%-85%) of cancer patients in the United States receive their care. Citation Format: Rachel B Keller, Tali Mazor, Marios Giannakis, Jonathan Nowak, Lynette Sholl, Andrew Aguirre, Adam Bass, Nilay Sethi, Ankur Nagaraja, Lauren Brais, Emma Reilly, Ethan Cerami, Brian Wolpin. Precision oncology decision support within the Gastrointestinal Cancer Center at Dana-Farber Cancer Institute (GI TARGET) [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C130. doi:10.1158/1535-7163.TARG-19-C130

ACTR-47. PHASE-III TRIAL OF STANDARD CHEMOTHERAPY VS. CHEMOTHERAPY GUIDED BY CANCER STEM CELL TEST IN RECURRENT GLIOBLASTOMA (NCT03632135)

Abstract Stupp treatment protocol for patients with glioblastoma (GBM) has improved the median overall survival to 14.6 months. However, no investigations have defined effective strategies against recurrence and the prognosis of recurrent GBM patients remains poor. Personalized medicine with assay-guided treatment targeting chemotherapy resistant cancer stem cells (CSCs) alongside the bulk tumor cells is a new paradigm in cancer treatment that may result in improved patient’s outcome. We are using ChemoID, a CLIA and CAP certified CSC cytotoxicity assay for predicting response to chemotherapeutic agents. Our prospective analysis of 61 GBM patients demonstrated that ChemoID-guided treatment significantly improved tumor response. For every 5% increase in cell kill of CSCs by assay-guided chemotherapy, 12-month patient response (non-recurrence of cancer) increased 2.5-fold, OR=2.3 (p=0.01). We also found that median recurrence time was 20-months versus 3-months for patients with a positive (>40% cell kill) CSC test versus negative, whereas median recurrence time was 13-months versus 4-months for patients with a positive (>55% cell kill) bulk test versus negative. We are conducting a multi-institutional phase-III clinical trial (NCT03632135) to determine the clinical validity of the ChemoID assay as a predictor of clinical response in recurrent GBM. The study has been designed as a parallel group controlled clinical trial and the participants are randomized to either standard of care chemotherapy chosen by the physician or ChemoID-guided therapy. Response to therapy will be measured by MRI imaging using RANO criteria. Primary endpoint of median overall survival (OS) and secondary endpoints of OS at 6, 9, and 12 months, median progression free survival (PFS), PFS at 4, 6, 9, and 12 months, objective tumor response, time to recurrence, and quality of life will be measured. Trial is open and currently 22 subjects have been enrolled. Interim analysis of the trial will be conducted in approximately 12 months.