Enormous progress has been made to treat cancer, and yet the mortality rate of cancer remains unacceptably high. High clinical resistance to molecularly targeted therapeutics has pushed interest again towards inhibiting universal biochemical hallmarks of cancer. Recent evidence suggests that malignant tumors acidify the local extracellular environment to activate proteases for degrading the tumor matrix, which facilitates metastasis, and explains why more aggressive tumors are more acidic. Current therapies have only focused on using the low pH for enhancing drug release in tumors, thereby still relying on the traditional paradigm of intracellular inhibition of pathways, a method that continues to have mixed results. Thus, the goal of this proposal is to better eradicate cancer by developing a synergistic bifunctional nanoparticle platform that can both modulate the acidic extracellular environment (pHe) and deliver intracellular therapeutics. We propose:
(Aim 1) Local long term neutralization of tumor pHe will inhibit tumor growth. Acid-neutralizing nanoparticles will be anchored to the local extracellular microenvironment by being covalently attached to a polypeptide that inserts into tumor plasma membranes under acidic conditions. pH change and treatment response in murine tumor models will be assessed by fluorescent pH probes.
(Aim 2) Intracellular drug action combined with longitudinal neutralization of pHe of tumors will be synergistic. Doxorubicin will be linked to the internalizing segment of the nanoparticle-labeled peptide anchor. This dual acting therapy will be compared to traditional intracellular treatment in terms of tumor cells in vitro and in vivo treatment response. This research will develop a novel platform that can be made to monitor and modify the critical tumor extracellular environment as well as retain the ability for synergistic intracellular drug delivery Thus, this platform will be able to shift the paradigm of current cancer therapy from a solely intracellular approach to a dual (extracellular + intracellular) synergistic method of targeting cancer. By specifically neutralizing the tumor extracellular microenvironment, the proposed platform aims to prevent tumor progression and metastasis as well as minimize the traditional intracellular based pathways of resistance. Because of the broad universal aspect of low extracellular pH in cancer, particularly in the more malignant tumors, this platform will have also wide applicability, with particular potency on the most aggressive of cancers.

Public Health Relevance

Recent data suggest that low extracellular pH is integral for tumor progression across multiple cancer subtypes. However, no current platform exists that persistently targets this unique hallmark of cancer. The proposed research opens the door to a new extracellular therapeutic paradigm that prevents tumor progression and metastasis via the development of a novel therapeutic platform that is able to locally normalize the extracellular pH and synergistically treat cancer intracellularly.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Individual Predoctoral NRSA for M.D./Ph.D. Fellowships (ADAMHA) (F30)
Project #
5F30CA189435-04
Application #
9308918
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Damico, Mark W
Project Start
2014-07-01
Project End
2018-05-18
Budget Start
2017-07-01
Budget End
2018-05-18
Support Year
4
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Washington University
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Tricarico, Christopher; Peters, Robert; Som, Avik et al. (2017) EpxMedTracking: Feasibility Evaluation of an SMS-Based Medication Adherence Tracking System in Community Practice. JMIR Res Protoc 6:e87
Som, A; Groenendyk, J; An, T et al. (2017) Improving Dialysis Adherence for High Risk Patients Using Automated Messaging: Proof of Concept. Sci Rep 7:4177
Som, Avik; Raliya, Ramesh; Tian, Limei et al. (2016) Monodispersed calcium carbonate nanoparticles modulate local pH and inhibit tumor growth in vivo. Nanoscale 8:12639-47
Raliya, Ramesh; Som, Avik; Shetty, Nishit et al. (2016) Nano-antacids enhance pH neutralization beyond their bulk counterparts: synthesis and characterization. RSC Adv 6:54331-54335
Som, Avik; Bloch, Sharon; Ippolito, Joseph E et al. (2016) Acidic extracellular pH of tumors induces octamer-binding transcription factor 4 expression in murine fibroblasts in vitro and in vivo. Sci Rep 6:27803
Ippolito, Joseph E; Brandenburg, Matthew W; Ge, Xia et al. (2016) Extracellular pH Modulates Neuroendocrine Prostate Cancer Cell Metabolism and Susceptibility to the Mitochondrial Inhibitor Niclosamide. PLoS One 11:e0159675
Mondal, Suman B; Gao, Shengkui; Zhu, Nan et al. (2015) Binocular Goggle Augmented Imaging and Navigation System provides real-time fluorescence image guidance for tumor resection and sentinel lymph node mapping. Sci Rep 5:12117
Gilson, Rebecca C; Tang, Rui; Som, Avik et al. (2015) Protonation and Trapping of a Small pH-Sensitive Near-Infrared Fluorescent Molecule in the Acidic Tumor Environment Delineate Diverse Tumors in Vivo. Mol Pharm 12:4237-46
Som, Avik; Charanya, Tauseef; Linderman, Stephen W et al. (2014) Bridging the gap between invention and commercialization in medical devices. Nat Biotechnol 32:1063-5