Editor’s note: since the original publishing date of this article, the Azure c600 Imager has been updated to the Azure 600 Imager. Learn more about expanded imaging capabilities of the Azure 600 by clicking here.
In a recent publication, Dostablova et al used the fluorescence imaging capacity of the Azure c600 imager in a creative way, detecting the inherent fluorescence of an anti-cancer drug, as part of their investigation into a novel anti-cancer treatment.
Prostate-Specific Membrane Antigen-Targeted Site-Directed Antibody-Conjugated Apoferritin Nanovehicle Favorably Influences In Vivo Side Effects of Doxorubicin. Dostalova S, et al. Scientific Reports. 11 June 2018. 8:8867. PMID: 29891921.
Doxorubicin-DNA complex. By Fvasconcellos 19:11, 28 November 2007 (UTC) – From PDB entry 1D12.More information:Frederick CA, Williams LD, Ughetto G, et al. (1990). “Structural comparison of anticancer drug-DNA complexes: adriamycin and daunomycin”. Biochemistry 29 (10): 2538–49. PMID 2334681., Public Domain, https://commons.wikimedia.org/w/index.php?curid=3158967
Combating toxicity of anti-cancer therapies
Anti-cancer treatments often are associated with adverse side effects. An approach to reducing the toxicity of anti-cancer drugs is to coat the drug in another substance, called a “nanocarrier.” The nanocarrier can alter drug delivery or absorption, improving delivery to the tumor and/or reducing delivery to other tissues. According to the authors, an ideal nanocarrier is nontoxic, biocompatible, and biodegradable.
Doxorubicin is an anti-cancer drug indicated for the treatment of breast cancer, prostate cancer, leukemia, and many other cancer types. Doxorubicin is associated with multiple adverse effects, the most dangerous of which is dilated cardiomyopathy which can lead to congestive heart failure.
Dostloava et al reported the effects on safety and efficacy of encapsulating doxorubicin with the protein apoferritin (APO). The authors studied both doxorubicin-apoferrin particles (APODOX), as well as a form of APODOX targeted to prostate tumors by conjugating the particles to an anti–prostate specific membrane antigen (PSMA) antibody (APODOX-anti-PSMA).
Detecting doxorubicin fluorescence with the Azure c600
In the course of establishing their experimental system, the authors characterized two prostate cancer cell lines to determine whether cellular proteins bound to APODOX-anti-PSMA. They developed an in vitro assay taking advantage of the fluorescence properties of the anti-cancer drug doxorubicin within the APODOX complex. In this assay, similar to a Western blot, cell proteins were separated on a gel and transferred to a PVDF membrane.
The membrane was then incubated with APODOX-anti-PSMA overnight, and washed. Bound APODOX-anti-PSMA was detected by measuring doxorubicin fluorescence using the Azure c600, with an excitation wavelength of 550 nm and emission wavelength of 570 nm. Levels were quantified via densitometry using AzureSpot software.
The APODOX-anti-PSMA was subsequently tested in a mouse model of prostate cancer and the targeted drug was found to attenuate tumors while reducing the damage to kidney and liver tissue that was observed with non-targeted APODOX.