CD133-targeted paclitaxel delivery inhibits local tumor recurrence in a mouse model of breast cancer
Graphical abstract
A small subset tumor cells, known as tumor initiating cells (TICs) are responsible for tumor recurrence. Targeting drug loaded nanoparticles to CD133 protein expressed on TICs leads to inhibition of tumor recurrence.
Introduction
Disease recurrence after an initial response to treatment is a significant problem in breast and other solid tumors [1], [2]. Recent studies suggest that a small subset of tumor cells, known as tumor initiating cells (TICs) or cancer stem cells (CSCs), are responsible for tumor recurrence [3], [4]. TICs have the ability to initiate new tumors and drive their subsequent growth [5], [6]. TICs are highly resistant to conventional treatments including chemotherapy [7], [8] and radiation [9]. Many factors including overexpression of drug efflux proteins [10] as well as DNA-repair proteins [11], elevated levels of antioxidants [12], and slower cell division [13] contribute to resistance. New therapies that can efficiently eradicate TICs are needed to prevent tumor recurrence.
Expression of CD133 (Prominin-1) is widely used as a marker to identify neural, endothelial and hematopoietic stem cells [14], [15], [16] as well as TICs in brain [17], colon [18], prostate [19], pancreatic [20] and breast tumors [21]. CD133 is a 120 kDa glycoprotein that localizes to plasma membrane [22]. Its molecular function is yet to be completely characterized. However, its expression is used to enrich for TICs in breast cancer [23]. CD133 + tumor cells are able to form complete tumors under limiting dilution. Importantly, CD133 expression has been correlated with tumor recurrence in breast cancer patients [24].
The objective of this study was to evaluate the therapeutic effectiveness of delivering paclitaxel, a microtubule-stabilizing anticancer drug, targeted to CD133 + tumor cells. Nanoparticles formulated using the biodegradable poly(D,L lactide-co-glycolide) (PLGA) polymer and surface functionalized with an anti-CD133 antibody (CD133NPs) were developed for targeting TICs. The formulation was characterized for its effectiveness against TICs in cell culture studies and for its ability to inhibit tumor recurrence in a mouse model of breast cancer. Our studies show that encapsulation of paclitaxel in CD133-targeted nanoparticles results in significantly improved therapeutic efficacy and reduced local tumor recurrence.
Section snippets
Materials
PLGA (lactide to glycolide ratio 50:50; average Mw 40 kDa) was purchased from Absorbable polymers, Pelham, AL; hydroxyl PEG maleimide was purchased from Laysan Bio Inc., Arab, AL; polyvinyl alcohol (PVA; molecular weight 30–70 kDa) was obtained from Sigma, St. Louis, MO; HPLC grade organic solvents and plasticware were obtained from Fisher Scientific, Pittsburgh, PA. All general reagents were purchased from Sigma, St. Louis, MO, unless indicated otherwise. Caco-2 (colorectal adenocarcinoma) and
Characterization of antibody conjugated nanoparticles
The mean hydrodynamic diameter of non-functionalized nanoparticles was about 215 nm. The particle size increased to ~ 320 nm following antibody conjugation (Table 1). All the nanoparticle formulations had a net negative surface charge. Paclitaxel was efficiently encapsulated in nanoparticles (> 90% encapsulation efficiency at 12 ± 0.6% w/w loading). Conjugation of anti-CD133 antibody or IgG isotype control to nanoparticles was confirmed by Western blotting (Fig. 1B). Bands corresponding to the heavy
Discussion
The concept of a TIC implies the existence of a hierarchy within tumor cells, in which only a small subset of cells are endowed with stem cell-like features of self-renewal, asymmetric cell division and partial differentiation [6], [34]. TICs are considered to be responsible for tumor origin and its subsequent uncontrolled growth. The cellular origin of TICs is not completely understood. However, the existence of TICs is firmly established in several tumor types including myelogenous leukemia
Conclusion
Polymeric nanoparticles loaded with paclitaxel and surface functionalized with anti-CD133 antibody demonstrated efficient elimination of TICs in vitro and significant inhibition of tumor-regrowth in vivo. The results of our study thus suggest that CD133 is a potential target for directed delivery of anticancer therapeutics and that by eliminating CD133 + cells, it is possible to reduce tumor recurrence in breast cancer. Additional studies investigating a more suitable targeting ligand and
Acknowledgments
We thank the following people at the University of Minnesota: Brenda Koniar and Steve Kalscheuer for help with animal studies; Dr. Deepali Sachdev for help with soft agar colony assay protocol; Colleen Forster for assistance with immunohistochemistry; Dr. David Largaespada for allowing us to use the hematology analyzer. We thank the flow cytometry core facility and the Biological Image Processing Laboratory at the University of Minnesota for their assistance. Funding from Randy Shaver foundation
References (64)
- et al.
AC133, a novel marker for human hematopoietic stem and progenitor cells
Blood
(1997) - et al.
The use of nanoparticle-mediated targeted gene silencing and drug delivery to overcome tumor drug resistance
Biomaterials
(2010) - et al.
Identification of a novel monoclonal antibody recognizing CD133
J. Immunol. Methods
(2010) - et al.
CD133-positive cells are resistant to TRAIL due to up-regulation of FLIP
Biochem. Biophys. Res. Commun.
(2008) - et al.
Biodegradable nanoparticles for drug and gene delivery to cells and tissue
Adv. Drug Deliv. Rev.
(2003) - et al.
Identification of selective inhibitors of cancer stem cells by high-throughput screening
Cell
(2009) Breast cancer in young women
Nat. Rev. Clin. Oncol.
(2012)- et al.
Breast cancer: understanding sensitivity and resistance to chemotherapy and targeted therapies to aid in personalised medicine
Curr. Cancer Drug Targets
(2009) - et al.
Survival of the fittest: cancer stem cells in therapeutic resistance and angiogenesis
J. Clin. Oncol.
(2008) - et al.
Cancerous stem cells: deviant stem cells with cancer-causing misbehavior
Stem Cell Res. Ther.
(2010)
Self-renewal and solid tumor stem cells
Oncogene
Cancer stem cells: a step toward the cure
J. Clin. Oncol.
Tumour stem cells and drug resistance
Nat. Rev. Cancer
Quantitation of differential sensitivity of human-tumor stem cells to anticancer drugs
N. Engl. J. Med.
Glioma stem cells promote radioresistance by preferential activation of the DNA damage response
Nature
Multidrug efflux pumps and cancer stem cells: insights into multidrug resistance and therapeutic development
Clin. Pharmacol. Ther.
Association of reactive oxygen species levels and radioresistance in cancer stem cells
Nature
Targeting cancer cells by ROS-mediated mechanisms: a radical therapeutic approach?
Nat. Rev. Drug Discov.
Quiescent, slow-cycling stem cell populations in cancer: a review of the evidence and discussion of significance
J. Oncol.
Prominin, a novel microvilli-specific polytopic membrane protein of the apical surface of epithelial cells, is targeted to plasmalemmal protrusions of non-epithelial cells
Proc. Natl. Acad. Sci. U. S. A.
Direct isolation of human central nervous system stem cells
Proc. Natl. Acad. Sci. U. S. A.
CD133 is essential for glioblastoma stem cell maintenance
Stem Cells
CD133 as a target for colon cancer
Expert Opin. Ther. Targets
Identification of putative stem cell markers, CD133 and CXCR4, in hTERT-immortalized primary nonmalignant and malignant tumor-derived human prostate epithelial cell lines and in prostate cancer specimens
Cancer Res.
Prominin-1 (CD133) reveals new faces of pancreatic progenitor cells and cancer stem cells: current knowledge and therapeutic perspectives
Adv. Exp. Med. Biol.
CD44posCD49fhiCD133/2hi defines xenograft-initiating cells in estrogen receptor-negative breast cancer
Cancer Res.
CD133: molecule of the moment
J. Pathol.
Brca1 breast tumors contain distinct CD44 +/CD24 − and CD133 + cells with cancer stem cell characteristics
Breast Cancer Res.
CD133 is a useful surrogate marker for predicting chemosensitivity to neoadjuvant chemotherapy in breast cancer
PLoS One
Interfacial activity assisted surface functionalization: a novel approach to incorporate maleimide functional groups and cRGD peptide on polymeric nanoparticles for targeted drug delivery
Mol. Pharm.
Folic acid functionalized nanoparticles for enhanced oral drug delivery
Mol. Pharm.
In vitro propagation and transcriptional profiling of human mammary stem/progenitor cells
Genes Dev.
Cited by (150)
Novel insight into cancer treatment: Recent advances and new challenges
2024, Journal of Drug Delivery Science and TechnologyBiomarkers and targeted therapy for cancer stem cells
2024, Trends in Pharmacological SciencesShrinking the battlefield in cancer therapy: Nanotechnology against cancer stem cells
2023, European Journal of Pharmaceutical SciencesEffective suppression of triple negative breast cancer by paclitaxel nanoparticles conjugated with transmembrane TNF-α monoclonal antibody
2022, International Journal of PharmaceuticsTriple-negative breast cancer treatment meets nanoparticles: Current status and future direction
2022, Journal of Drug Delivery Science and TechnologyRole, molecular mechanism and the potential target of breast cancer stem cells in breast cancer development
2022, Biomedicine and Pharmacotherapy
- 1
J.R.O is now deceased.