Near-Infrared Fluorescent Agent for In Vitro Screening of Endometrial Cancer and Precancerous Lesions.

Dongxin Liang,Xue Feng,Kailu Zhang,Lanbo Zhao,Yiran Wang,Yu Liu,Lin Guo,Qiling Li,Panyue Yin,Qing Wang,Xiaoqian Tuo,Lu Han,Lei Wang,Ruifang An

doi:10.3389/fonc.2021.713583

Abstract

The lack of cytopathologists delays the advancement of screening for endometrial cancer. It was urgent to develop a new dye for rapid diagnosis. Our study aimed to synthesize a targeted folate receptor-α near-infrared (NIR) fluorescent agent, folic acid-zwitterionic NIR fluorophore (ZW-FA), and explore the feasibility for screening of endometrial cancer and precancerous change. Folic acid was conjugated with zwitterionic NIR fluorophore. The preparation of ZW-FA was validated by 1H NMR, mass spectrometric, ultraviolet spectra and fluorescence spectra. ZW-FA was incubated with endometrial cytology samples obtained from patients who underwent dilation and curettage or total hysterectomy. Diagnostic utility was calculated by applying laser confocal microscope, Image-J and statistical models, such as enumeration, receiver operating characteristic curve, logistic regression, support vector machine and decision tree were used. The purity of ZW-FA was > 95% determined by 1H NMR. ZW-FA had the strongest absorption peak at 633 nm in ultraviolet spectra. Photostability of ZW-FA was over 8 hours. In clinical validation, a total of 92 patients were enrolled. The cut-off value of ZW-FA was 49 in enumeration, which was used to distinguish the type of samples. Indicators about diagnostic utility are as follows: sensitivity 90.77%, specificity 62.96%, false-positive rate 37.04%, false-negative rate 9.23%, positive predictive value 85.51% and negative predictive value 73.91%. The samples processed by ZW-FA did not affect further Hematoxylin-Eosin staining and pathological diagnosis. It was an effective cytologic strategy for in vitro diagnosis of endometrial cancer and precancerous change by using ZW-FA.Clinical Trial Registration http://www.chictr.org.cn/index.aspx, identifier ChiCTR1800020123.

Highlights

Endometrial cancer is the most common malignancy of the female reproductive system in developed countries [1]
The synthesis procedure of ZW-FA was presented in Figure 1A and Supplementary Table 1
The results demonstrated that the Folate receptor-a (FR-a) on the cell surface was firstly occupied by the human folate receptor alpha-1 (FOLR1) antibody, resulting in the binding of ZW-FA was blocked

Summary

INTRODUCTION

Endometrial cancer is the most common malignancy of the female reproductive system in developed countries [1]. Overexpression of FR-a has been reported in various solid tumours such as endometrial cancer, ovarian cancer, breast carcinoma, non–small cell lung cancer and so on [10,11,12,13]. High expression of FR-a was found in 12%-50.5% of endometrioid cancers, 33%-41% of serous cancers, and 25% of clear cell cancers [14,15,16,17]. Results of a combination of folic acid and high-density lipoprotein fluorescent nanoparticles showed that with the linking of folic acid, the uptake of fluorescent nanoparticles in ovarian cancer tissues significantly increased, which is an excellent targeted drug [23]. After completing the synthesis and characterization of ZW-FA, a cytologic test for in vitro diagnosis of endometrial cancer and precancerous change was proposed to verify the feasibility

MATERIALS AND METHODS

RESULTS

DISCUSSION

ETHICS STATEMENT