Quantum Dot-labeled Tags Improve Minimal Detection Limit of CA125 in Ovarian Cancer Cells and Tissues

Abstract

In recent years, a lot of attention has been paid to quantum dot (QD) nanoparticles as fluorescent sensors for sensitive and accurate detection of cancer biomarkers.
 Here, using a homemade specific monoclonal antibody against CA125 and QD525- or FITC-labeled probes, expression of this marker in an ovarian cancer cell line and cancer tissues were traced and optical properties of fluorophores were compared qualitatively and quantitatively.
 Our results clearly showed that besides lower background and exceptionally higher photobleaching resistance, QD525 exhibited higher fluorescent intensity for both ovarian cancer cell and tissues at different exposure times (p<0.0001) and excitation filter sets (p<0.0001) exemplified by significantly higher staining index (p<0.016). More importantly, the FITC-labeled probe detected antigen-antibody complex at minimum concentration of 0.3 mg/mL of anti-CA125, while reactivity limit decreased to 0.078 mg/mL of anti-CA125 when QD525-labeled probe was applied showing four times higher reactivity level of QD525 probe compared to the same probe labeled with FITC.
 Based on our results, it seems that QDs are inimitable tags for sensitive detection and localization of ovarian cancer micrometastasis and molecular demarcation of cancer tissues in surgical practice, which subsequently figure out accurate therapeutic approaches.

Applications of Quantum Dots in Preventive Oncology

“…This makes it possible to track the delivery of drugs and how they affect cancer cells in real-time. To find cancer biomarkers in blood or other bodily fluids, QD can be incorporated into biosensors [25][26][27]. Early-stage cancer can be detected by alterations in the fluorescence characteristics of QDs when certain biomolecules are present.…”

Classification and applications of nanomaterials in vitro diagnosis

“…QDs stand out for their high quantum yield, high molar extinction coefficient, wide absorption range, strong photobleaching resistance, and outstanding degradation performance. Recent studies have used QD-based biosensors to detect cancer biomarkers, such as the detection of ovarian cancer CA-125 biomarker using QDs junction fitting [ 92 ], and the detection of PSA antigen by side-flow technology using QDs embedded with silica nanoparticles [ 93 ], as well as the detection of CEA and AFP antigens [ [93] , [94] , [95] ]. Meanwhile, AuNPs can detect cancer-related markers such as tumor DNA or cells and exosomes.…”

Detection Systems in Immunohistochemistry

“…There are some exceptions to this rule. For example, in tumor-specific antigens, which are not expressed in normal condition, the use of more sensitive methods might decrease detection level cutoff and increase the likelihood for early detection of cancer [143,144].…”