Prolonged Cadmium Exposure Alters Migration Dynamics and Increases Heterogeneity of Human Uterine Fibroid Cells-Insights from Time Lapse Analysis

Yitang Yan; Min Shi; Rick Fannin; Linda Yu; Jingli Liu; Lysandra Castro; Darlene Dixon

doi:10.3390/biomedicines10040917

Prolonged Cadmium Exposure Alters Migration Dynamics and Increases Heterogeneity of Human Uterine Fibroid Cells-Insights from Time Lapse Analysis

Biomedicines. 2022 Apr 16;10(4):917. doi: 10.3390/biomedicines10040917.

Authors

Yitang Yan¹, Min Shi², Rick Fannin³, Linda Yu¹, Jingli Liu¹, Lysandra Castro¹, Darlene Dixon¹

Affiliations

¹ Molecular Pathogenesis Group, Mechanistic Toxicology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, 111 TW Alexander Drive, Durham, NC 27709, USA.
² Biostatistics & Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, 111 TW Alexander Drive, Durham, NC 27709, USA.
³ Molecular Genomics Core Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 TW Alexander Drive, Durham, NC 27709, USA.

Abstract

Cadmium (Cd) is one of the most prevalent environmental heavy metal contaminants and is considered an endocrine disruptor and carcinogen. In women with uterine fibroids, there is a correlation between blood Cd levels and fibroid tumor size. In this study, fibroid cells were exposed to 10 µM CdCl₂ for 6 months and a fast-growing Cd-Resistant Leiomyoma culture, termed CR-LM6, was recovered. To characterize the morphological and mechanodynamic features of uterine fibroid cells associated with prolonged Cd exposure, we conducted time lapse imaging using a Zeiss confocal microscope and analyzed data by Imaris and RStudio. Our experiments recorded more than 64,000 trackable nuclear surface objects, with each having multiple parameters such as nuclear size and shape, speed, location, orientation, track length, and track straightness. Quantitative analysis revealed that prolonged Cd exposure significantly altered cell migration behavior, such as increased track length and reduced track straightness. Cd exposure also significantly increased the heterogeneity in nuclear size. Additionally, Cd significantly increased the median and variance of instantaneous speed, indicating that Cd exposure results in higher speed and greater variation in motility. Profiling of mRNA by NanoString analysis and Ingenuity Pathway Analysis (IPA) strongly suggested that the direction of gene expression changes due to Cd exposure enhanced cell movement and invasion. The altered expression of extracellular matrix (ECM) genes such as collagens, matrix metallopeptidases (MMPs), secreted phosphoprotein 1 (SPP1), which are important for migration contact guidance, may be responsible for the greater heterogeneity. The significantly increased heterogeneity of nuclear size, speed, and altered migration patterns may be a prerequisite for fibroid cells to attain characteristics favorable for cancer progression, invasion, and metastasis.

Keywords: Ingenuity Pathway Analysis; cadmium; carcinogenesis; fibroid; heterogeneity; migration; straightness; time lapse; variance.

Grants and funding

ES021196-27/ES/NIEHS NIH HHS/United States