Adenoid cystic carcinomas (ACC) are rare salivary gland cancers with a high incidence of metastases. In order to study this tumor type, a reliable model system exhibiting the molecular features of this tumor is critical, but none exists, thereby inhibiting in-vitro studies and the analysis of metastatic behavior. To address this deficiency, we have coupled an efficient method to establish tumor cell cultures, conditional reprogramming (CR), with a rapid, reproducible and robust in-vivo zebrafish model. We have established cell cultures from two individual ACC PDX tumors that maintain the characteristic MYB translocation. Additional mutations found in one ACC culture also seen in the PDX tumor. Finally, the CR/zebrafish model mirrors the PDX mouse model and identifies regorafenib as a potential therapeutic drug to treat this cancer type that mimic the drug sensitivity profile in PDX model, further confirming the unique advantages of multiplex system.

The identification and prioritization of chemically tractable therapeutic targets is a significant challenge in the discovery of new medicines. We have developed a novel method that rapidly screens multiple proteins in parallel using DNA-encoded library technology (ELT). Initial efforts were focused on the efficient discovery of antibacterial leads against 119 targets from Acinetobacter baumannii and Staphylococcus aureus. The success of this effort led to the hypothesis that the relative number of ELT binders alone could be used to assess the ligandability of large sets of proteins. This concept was further explored by screening 42 targets from Mycobacterium tuberculosis. Active chemical series for six targets from our initial effort as well as three chemotypes for DHFR from M. tuberculosis are reported. The findings demonstrate that parallel ELT selections can be used to assess ligandability and highlight opportunities for successful lead and tool discovery.

Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Patient survival has remained largely the same for the past 20 years, with therapies causing significant health, cognitive, behavioral and developmental complications for those who survive the tumor. In this study, we profiled the total transcriptome and proteome of two established MB cell lines, Daoy and UW228, using high-throughput RNA sequencing (RNA-Seq) and label-free nano-LC-MS/MS-based quantitative proteomics, coupled with advanced pathway analysis. While Daoy has been suggested to belong to the sonic hedgehog (SHH) subtype, the exact UW228 subtype is not yet clearly established. Thus, a goal of this study was to identify protein markers and pathways that would help elucidate their subtype classification. A number of differentially expressed genes and proteins, including a number of adhesion, cytoskeletal and signaling molecules, were observed between the two cell lines. While several cancer-associated genes/proteins exhibited similar expression across the two cell lines, upregulation of a number of signature proteins and enrichment of key components of SHH and WNT signaling pathways were uniquely observed in Daoy and UW228, respectively. The novel information on differentially expressed genes/proteins and enriched pathways provide insights into the biology of MB, which could help elucidate their subtype classification.

A major barrier to the successful application of nanotechnology for cancer treatment is the suboptimal delivery of therapeutic payloads to metastatic tumor deposits. We previously discovered that cabozantinib, a tyrosine kinase inhibitor, triggers neutrophil-mediated anticancer innate immunity, resulting in tumor regression in an aggressive PTEN/p53-deficient genetically engineered murine model of advanced prostate cancer. Here, we specifically investigated the potential of cabozantinib-induced neutrophil activation and recruitment to enhance delivery of BSA-coated polymeric nanoparticles (BSA-NPs) into murine PTEN/p53-deficient prostate tumors. On the basis of the observation that BSA coating of NPs enhanced association and internalization by activated neutrophils by approximately 6-fold in vitro, relative to uncoated NPs, we systemically injected BSA-coated, dye-loaded NPs into prostate-specific PTEN/p53-deficient mice that were pretreated with cabozantinib. Flow cytometric analysis revealed an approximately 4-fold increase of neutrophil-associated BSA-NPs and an approximately 32-fold increase in mean fluorescent dye uptake following 3 days of cabozantinib/BSA-NP administration, relative to BSA-NP alone. Strikingly, neutrophil depletion with Ly6G antibody abolished dye-loaded BSA-NP accumulation within tumors to baseline levels, demonstrating targeted neutrophil-mediated intratumoral NP delivery. Furthermore, we observed an approximately 13-fold decrease in accumulation of BSA-NPs in the liver, relative to uncoated NPs, post-cabozantinib treatment, suggesting that BSA coating of NPs can significantly enhance cabozantinib-induced, neutrophil-mediated targeted intratumoral drug delivery, while mitigating off-target toxicity. Collectively, we demonstrate a novel targeted nano-immunotherapeutic strategy for enhanced intratumoral delivery of BSA-NPs, with translational potential to significantly augment therapeutic indices of cancer medicines, thereby overcoming current pharmacologic barriers commonly encountered in preclinical/early-phase drug development.