Project description:Purpose: Accumulating analyses of pro-oncogenic molecular mechanisms triggered a rapid development of targeted cancer therapies. Although many of these treatments produce impressive initial responses, eventual resistance onset is practically unavoidable. One of the main approaches for preventing this refractory condition relies on the implementation of combination therapies. This includes dual-specificity reagents that affect both of their targets with a high level of selectivity. Unfortunately, selection of target combinations for these treatments is often confounded by limitations in our understanding of tumor biology. Here, we describe and validate a multipronged unbiased strategy for predicting optimal co-targets for bispecific therapeutics. Experimental design: Our strategy integrates ex-vivo genome-wide loss of function screening, BioID interactome profiling and gene expression analysis of patient data to identify the best fit co-targets. Final validation of selected target combinations is done in tumorsphere cultures and xenograft models. Results: Integration of our experimental approaches unambiguously pointed towards EGFR and EPHA2 tyrosine kinase receptors as molecules of choice for co-targeting in multiple tumor types. Following this lead, we generated a human bispecific anti-EGFR/EPHA2 antibody that, as predicted, very effectively suppresses tumor growth, compared to its prototype anti-EGFR therapeutic antibody, cetuximab. Conclusion: Our work not only presents a new bispecific antibody with a high potential for being developed into clinically-relevant biologics, but more importantly, successfully validates a novel unbiased strategy for selecting biologically optimal target combinations. This is of a significant translational relevance, as such multifaceted unbiased approaches are likely to augment the development of effective combination therapies for cancer treatment.
Project description:Recent progress in dissecting molecular mechanisms essential for the survival and propagation of cancer cells triggered rapid development of targeted therapies. Although many of these therapies produce impressive initial responses in tumor suppression, the onset of resistance is practically unavoidable. One of the main approaches for preventing this refractory condition relies on the development of effective combination therapies. Unfortunately, selection of optimal targets for combinatorial treatments is often confounded by limitations in our understanding of tumor biology. Here, we describe an unbiased comprehensive strategy that combines ex-vivo shRNA-based genome wide screening, proteomic profiling using BioID and patient tumor sequencing data analyses to overcome current challenges in identifying the best fit co-targeting agents. Integrating these strategies, we selected EGFR and EPHA2 receptors as molecules of choice for co-targeting in cancer cells, and generated a bispecific fully humanized anti-EGFR/EPHA2 antibody with druggable bioanalytical properties that very effectively suppresses tumor growth compared to its prototype therapeutic anti-EGFR antibody, cetuximab. Despite the overactivation of EGFR signaling in multiple malignancies, the therapeutic applicability of cetuximab is limited due to frequent resistance and could benefit from being used in a combination with another targeted compound. Our analysis indicates that EGFR and EPHA2 expression positively correlate in various cancer types and thus, are available for co-targeting in most tumors. Therefore, our work not only presents an efficient unbiased strategy for selecting optimal targets for combination therapies, but also describes a novel bispecific antibody, which has a high potential for being developed into a new clinically-relevant biologics effective in a broad variety of malignancies.
Project description:EGF receptor (EGFR) tyrosine kinase inhibitors (TKIs) have achieved clinical successes in lung adenocarcinoma (LUAD). However, tumors often show profound but transient initial response and gain resistance. Here, we identified transcription factor ZNF263 as being significantly decreased in osimertinib-resistant or drug-tolerant persister LUAD cells and clinical residual tumor specimens. Exogenous expression of ZNF263 improved the initial response of cells and delayed the formation of persister cells with osimertinib. We elaborated that ZNF263 bound and recruited DNMT1 to the EGFR gene promoter, suppressing EGFR transcription with DNA hypermethylation. ZNF263 could also interact with nuclear EGFR (nEGFR), impairing the nEGFR-STAT5 interaction to enhance AURKA expression. Overexpressing ZNF263 also made tumor cells with wild-type EGFR expression or refractory EGFR mutations more susceptible to EGFR inhibition. More importantly, lentivirus or AAV-mediated plasmid delivery of ZNF263 synergistically suppressed tumor growth and regrowth with osimertinib in xenograft animal models. These findings suggest that enhancing ZNF263 may achieve complete response in LUAD with EGFR-targeted therapies.
Project description:EGF receptor (EGFR) tyrosine kinase inhibitors (TKIs) have achieved clinical successes in lung adenocarcinoma (LUAD). However, tumors often show profound but transient initial response and gain resistance. Here, we identified transcription factor ZNF263 as being significantly decreased in osimertinib-resistant or drug-tolerant persister LUAD cells and clinical residual tumor specimens. Exogenous expression of ZNF263 improved the initial response of cells and delayed the formation of persister cells with osimertinib. We elaborated that ZNF263 bound and recruited DNMT1 to the EGFR gene promoter, suppressing EGFR transcription with DNA hypermethylation. ZNF263 could also interact with nuclear EGFR (nEGFR), impairing the nEGFR-STAT5 interaction to enhance AURKA expression. Overexpressing ZNF263 also made tumor cells with wild-type EGFR expression or refractory EGFR mutations more susceptible to EGFR inhibition. More importantly, lentivirus or AAV-mediated plasmid delivery of ZNF263 synergistically suppressed tumor growth and regrowth with osimertinib in xenograft animal models. These findings suggest that enhancing ZNF263 may achieve complete response in LUAD with EGFR-targeted therapies.
Project description:EGF receptor (EGFR) tyrosine kinase inhibitors (TKIs) have achieved clinical successes in lung adenocarcinoma (LUAD). However, tumors often show profound but transient initial response and gain resistance. Here, we identified transcription factor ZNF263 as being significantly decreased in osimertinib-resistant or drug-tolerant persister LUAD cells and clinical residual tumor specimens. Exogenous expression of ZNF263 improved the initial response of cells and delayed the formation of persister cells with osimertinib. We elaborated that ZNF263 bound and recruited DNMT1 to the EGFR gene promoter, suppressing EGFR transcription with DNA hypermethylation. ZNF263 could also interact with nuclear EGFR (nEGFR), impairing the nEGFR-STAT5 interaction to enhance AURKA expression. Overexpressing ZNF263 also made tumor cells with wild-type EGFR expression or refractory EGFR mutations more susceptible to EGFR inhibition. More importantly, lentivirus or AAV-mediated plasmid delivery of ZNF263 synergistically suppressed tumor growth and regrowth with osimertinib in xenograft animal models. These findings suggest that enhancing ZNF263 may achieve complete response in LUAD with EGFR-targeted therapies.
Project description:Mass spectrometry-based quantitative proteomics profiling of in vivo signaling changes in 41 therapy resistant (osimertinib or EGFR/Met bispecific antibody treament) tumors from four xenograft NSCLC models.
Project description:We aimed to characterize the genomic profiles of adenocarcinomas in the gastroesophageal junction in relation to cancers in the esophagus and the stomach. Profiles of gains/losses as well as gene expression profiles were obtained from 27 gastroesophageal adenocarcinomas using 32k high-resolution array-based comparative genomic hybridization (aCGH) and 27k oligo gene expression arrays and putative target genes were validated in an extended series. Adenocarcinomas in the distal esophagus and the gastroesophageal junction showed strong similarities with the most common gains at 20q13, 8q24, 1q21-q23, 5p15, 13q34, and 12q13, whereas different profiles with gains at 5p15, 7p22, 2q35, and 13q34 characterized gastric cancers. CDK6 and EGFR were identified as putative target genes in cancers of the esophagus and the gastroesophageal junction with upregulation in one quarter of the tumors. Gains/losses and gene expression profiles show strong similarity between cancers in the distal esophagus and the gastroesophageal junction with frequent upregulation of CDK6 and EGFR, whereas gastric cancer displays distinct genetic changes. These data suggest that molecular diagnostics and targeted therapies can be applied to adenocarcinomas of the distal esophagus and gastroesophageal junction alike. Three types of gastroesophageal adenocarcinomas; 7 distal esophageal (EA) tumors, 9 junctional (JA) and 7 proximal stomach cancers (GA) was genomically profiled using tiling 32k BAC-arrays. Two replicates of tumors IDs 1-EA-CGH (replicate 1-EA-CGH-2), 12-EA-CGH (replicate 12-EA-CGH-2) and 18-EA-CGH (replicate 18-EA-CGH-2). Reference samples consist of a pool of male DNA (Promega, Madison, WI, USA).
Project description:We aimed to characterize the genomic profiles of adenocarcinomas in the gastroesophageal junction in relation to cancers in the esophagus and the stomach. Profiles of gains/losses as well as gene expression profiles were obtained from 27 gastroesophageal adenocarcinomas using 32k high-resolution array-based comparative genomic hybridization (aCGH) and 27k oligo gene expression arrays and putative target genes were validated in an extended series. Adenocarcinomas in the distal esophagus and the gastroesophageal junction showed strong similarities with the most common gains at 20q13, 8q24, 1q21-q23, 5p15, 13q34, and 12q13, whereas different profiles with gains at 5p15, 7p22, 2q35, and 13q34 characterized gastric cancers. CDK6 and EGFR were identified as putative target genes in cancers of the esophagus and the gastroesophageal junction with upregulation in one quarter of the tumors. Gains/losses and gene expression profiles show strong similarity between cancers in the distal esophagus and the gastroesophageal junction with frequent upregulation of CDK6 and EGFR, whereas gastric cancer displays distinct genetic changes. These data suggest that molecular diagnostics and targeted therapies can be applied to adenocarcinomas of the distal esophagus and gastroesophageal junction alike.
Project description:Functional screening on patient-derived organoids identifies a therapeutic bispecific antibody that triggers EGFR degradation in LGR5+ tumor cells