Abstract

Methodology has been developed recently in our Ottawa laboratory to obtain infrared spectra of intact biological tissues and whole cells with extremely high signal-to-noise ratio. This development has allowed us to evaluate the structural properties of biomolecules in tissue sections and exfoliated cells of human neoplasms by monitoring their infrared spectra (Refs. 2 and 3 and research submitted for publication). During this work we found that several changes in the infrared spectra of malignant tissues and cells are common to all cancers which we studied, including those of the colon, stomach, esophagus, skin, liver, cervix, and vagina (Refs. 2 and 3 and research submitted for publication). It is important to know the structural origin of these spectral changes, since they may reflect a step of a shared pathway in carcinogenesis. The most striking changes in the spectra that are common to various malignant tissues and cells are observed in the symmetric (ν_sPO₂⁻) and asymmetric (ν_asPO₂⁻) stretching bands of phosphodiester groups. These results suggest that in all cancerous tissues and cells studied to date most PO₂⁻ groups become hydrogen bonded and that the intermolecular packing among neighboring PO₂⁻ groups becomes closer. (Refs. 2 and 3 and research submitted for publication). Indirect evidence, discussed later, pointed to nucleic acids as the molecules mainly responsible for the observed changes in the ν_sPO₂⁻ and ν_asPO₂⁻ bands. Since any information concerning structural changes in nucleic acids associated with malignancy is potentially significant for our understanding of cancer, we sought to confirm the molecular origin of the phosphodiester stretching modes in the infrared spectra of tissues and whole cells. We therefore investigated the infrared spectra of human malignant colon tissues, cultured human colon adenocarcinoma cells, and the nuclei, DNA, RNA, and lipids isolated from the cultured adenocarcinoma cells. Moreover, the correlation of the intensities of the ν_as,PO₂⁻ and ,ν_sPO₂⁻ bands in the infrared spectra of human thymus and muscle tissues with their relative concentrations of nucleic acids in the cells has been studied.

Simulation of thermal field distribution in biological tissue and cell culture media irradiated with infrared wavelengths

Viktor Dremin, Irina Novikova, and Edik Rafailov
Opt. Express 30(13) 23078-23089 (2022)

Comparison of principal component analysis and biochemical component analysis in Raman spectroscopy for the discrimination of apoptosis and necrosis in K562 leukemia cells

Yi Hong Ong, Mayasari Lim, and Quan Liu
Opt. Express 20(20) 22158-22171 (2012)

Label-free detection of hydrogen peroxide-induced oxidative stress in human retinal pigment epithelium cells via laser tweezers Raman spectroscopy

Yang Chen, ZhiQiang Wang, Yan Huang, ShangYuan Feng, ZuCi Zheng, XiuJie Liu, and MengMeng Liu
Biomed. Opt. Express 10(2) 500-513 (2019)

Study on the chemodrug-induced effect in nasopharyngeal carcinoma cells using laser tweezer Raman spectroscopy

Sufang Qiu, Miaomiao Li, Jun Liu, Xiaochuan Chen, Ting Lin, Yunchao Xu, Yang Chen, Youliang Weng, Yuhui Pan, Shangyuan Feng, Xiandong Lin, Lurong Zhang, and Duo Lin
Biomed. Opt. Express 11(4) 1819-1833 (2020)

Identification and characterization of colorectal cancer using Raman spectroscopy and feature selection techniques

Shaoxin Li, Gong Chen, Yanjiao Zhang, Zhouyi Guo, Zhiming Liu, Junfa Xu, Xueqiang Li, and Lin Lin
Opt. Express 22(21) 25895-25908 (2014)