We present a general approach for the targeting and imaging of cancer cells using dendrimer-entrapped gold nanoparticles (Au DENPs). Au DENPs were found to be able to covalently link with targeting and imaging ligands for subsequent cancer-cell targeting and imaging. The Au DENPs linked with defined numbers of folic acid (FA) and fluorescein isothiocyanate (FI) molecules are water soluble, stable, and biocompatible. In vitro studies show that the FA- and FI-modified Au DENPs can specifically bind to KB cells (a human epithelial carcinoma cell line) that overexpress high-affinity folate receptors and they are internalized dominantly into lysosomes of target cells within 2 h. These findings demonstrate that Au DENPs may serve as a general platform for cancer imaging and therapeutics.

A general approach to modifying preformed dendrimerentrapped Au nanoparticles with different functionalities is proved to improve their biocompatibility.

A facile approach has been developed to encapsulate submicrometer-sized drug crystals into polymer multilayer capsules produced by sequential deposition of polymers onto the drug particle surfaces. 2-Methoxyestradiol (2-ME) is a hydrophobic metabolite of 17-beta estradiol, which has been demonstrated as a potential anticancer agent. It was selected as a model drug and was formulated into submicrometer-sized particles through fine milling followed by intense sonication in the presence of dipalmitoyl-dl-(R)-phosphatidylcholine (DPPC). The reserved positive charges on the 2-ME crystal surface by DPPC enhanced the water solubility of the particles and subsequent self-assembly of dextran sulfate (DS) and dextran (DN) multilayers through hydrogen bonding and physical adsorption. Upon the exposure of the drug capsules to ethanol, hollow DS/DN multilayer polymer shells can be formed. The encapsulation process and hollow polymer multilayer shell formation were confirmed by confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM), while the surface morphology of the formed drug capsules was investigated using scanning electron microscopy (SEM). In vitro studies show that the inhibitory effect of the formed 2-ME capsules is the same as that of the conventional formulation of 2-ME in a concentrated ethanol solution, as demonstrated by dramatic changes in cell morphology and significantly decreased viability of target cells. We also demonstrate that the change of the outermost layer of the drug capsules does not significantly influence its bioactivity. The presented strategy to encapsulate submicrometer-sized hydrophobic drug particles is expected to provide a general pathway to fabricate drug capsules for various biological applications.

Multifunctional gold nanocomposites, which were designed as dendrimer-entrapped gold nanoparticles functionalized with gadolinium, cyanine dye (Cy5.5), and folic acid, were synthesized to be used as the first dendrimer-based clinical nanoprobes for targeted X-ray computed tomography/magnetic resonance/optical trimodal imaging in vitro and in vivo of human non-small cell cancer cells.

Non-small cell lung cancer (NSCLC) is one of most common lung cancers in the general population. KRAS mutations occur in 15-30% of NSCLC. The mutation results in continuous activation of KRAS, triggering multiple kinase signaling pathways. The oncogenic features of KRAS mutations are in line with clinical observations that NSCLC patients with KRAS mutations have a worse prognosis with less benefit from chemotherapies. Although the targeted inhibition of KRAS G12C mutation in NSCLC has achieved remarkable success, the inhibition of KRAS G12D has not yet been successful. It has been reported that KRAS mutations can facilitate the development of immunosuppressive properties of the tumor microenvironment. Specifically, KRAS mutations can up-regulate regulatory T cell (Treg) population. Tumor Treating Fields (TTFields) are a cancer therapy based on noninvasive delivery of electric fields. Our current in vitro study was performed in peripheral blood mononuclear cells (PBMC) from a transgenic mouse lung cancer model with a KRAS G12D mutation. Our data showed that TTFields treatment decreased CD4+CD25+ Foxp3+ T cells intensity prepared from PBMC compared to untreated cells by flow cytometric determination. In addition, CD4+ T cells prepared from TTFields treated PBMC have enhanced IFN-γ expression levels compared to untreated PBMC. These results suggest TTFields treatment appear to correct the immunosuppressive properties created by KRAS mutations. Therefore, in vivo treatment for the inducible lung cancer with KRAS activating mutations is needed to confirm the in vitro results. In conclusion, TTFields are a potential therapeutic tool for NSCLC with KRAS G12D mutation. Citation Format: Suhe Wang, James R. Baker, Jesse Chen, Zhengyi Cao, Jayme Cannon. Tumor treating fields induce immune modulation in non-small cell lung cancer [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 2279.

Non-small cell lung cancer (NSCLC) is a significant health issue associated with morbidity and mortality. One of the important findings to emerge in NSCLC is that specific genetic mutations that lead to cancer development occur early in the disease process. Unfortunately, identifying NSCLC at its earliest stages when it is curable has been a challenge even in high risk individuals. These gene mutations, especially those involving the Kras protein, can “drive” the development of NSCLC cancer as they alter the regulation of cell growth or block programmed cell death. Mutations in Kras have been reported in 30% of lung cancer cases and are associated with worse outcomes. This neo-antigen cannot generate effective anti-tumor immunity, suggesting lack of a cellular, cytotoxic immune response to cancer cells on mucosal/epithelial surfaces. No effective therapies specifically targeting mutant Kras have been developed. To overcome poor immunogenicity of neo-antigen, newer adjuvants (NA), biocompatible nanoparticles, were used to enhance immune response. It has been reported NA can produce cytotoxic and mucosal immunity safely in humans. Producing this type of immune response to mutated Kras through immunization could produce a significant anti-tumor effect. In the current study, we first tested NA combined with mutated and wild type (MHC II) Kras peptides vaccine for immunogenicity on the same genetic background as the animals in the inducible tumor model. Our data have demonstrated that NA in combination with multiple Kras peptides can increase CD4+ and CD8+ T cell numbers in the draining lymph node cells and enhance antigen specific TH1 and TH17 responses by luminex and ELISpot to increase the ability of the vaccine to kill tumor cells and elicit long-lasting immune memory. Furthermore, we evaluated anti-tumor efficacy of this vaccine in tetracycline-inducible mouse model with Kras mutation. In this challenge model, vaccinated mice showed higher IFNɤ and IL-17 levels and decreased the tumor incidence significantly compared to PBS or peptides alone group. In conclusion, we have demonstrated the antigen-specific cellular immune responses and mononuclear cell infiltrates correlate with tumor prevention. Our data suggest that this novel vaccine could prevent the development of NSCLC after validation in an appropriate animal model. Citation Format: Suhe Wang, Zhengyi Cao, Jesse Chen, Janczak Katarzyna, James Baker. Prevention of non-small cell lung cancer with kras mutation using a novel peptide vaccine [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 3571.