Analysis of the relief of MCF-7 tumor cells during apoptisis on the basis of phase-contrast images obtained by laser interference microscopy

Abstract

Data on the surface topography of the cell makes it possible to predict its behavior and is an indicator to assess whether it is in a state of apoptosis, that is, in a state of death due to the activation of intracellular reactions; this state of a cell occurs both during normal development and as a result of a pathological process. A universal method for recording the state of the relief of the cell and its other mechanobiological parameters has not been developed, and therefore laser interference microscopy is promising for this purpose. The aim of this work is to evaluate the state of the surface of tumor cells during the apoptotic changes in breast cancer cells by analyzing the phase contrast (phase) images obtained by laser interference microscopy. The object of the study is the cells of the MCF-7 line (epithelial-like adenocarcinoma of the human mammary gland) in a native state and in a state of induced apoptosis under the action of doxorubicin. The analysis of the cell surface involves interpretation of data on the optical thickness of cells and their morphology through the construction of isolines. Based on the analysis of phase images of cells, their general morphometric parameters were determined. Visualization of optical data and their interpretation was performed using the ImageJ-Fiji software. According to the Wilcoxnon-Mann-Whitney test, the samples under study are significantly different in maximum diameter, perimeter, and sphericity coefficient. Based on the analysis of isolinear images, a diagram of the phase state of cells in a native state and in a state of apoptosis was constructed. According to the diagram, the cross-sectional area of apoptotic cells is generally much smaller than the cross-sectional area of native cells at the same height levels. The characteristics of cells within the framework of the proposed phase diagram are consistent with the morphological cell apoptosis signs, which are recorded using classical microscopic methods. The construction of the diagrams of the state of cells according to the parameters of their relief holds promise for assessing the cellular behavior, predicting it, as well as for analyzing the effect of drugs and therapeutic methods on pathological cells.