Abstract Metastatic prostate cancer colonizes the bone to pave the way for bone metastasis, leading to skeletal complications associated with poor prognosis and morbidity. This study demonstrates the feasibility of Raman imaging to differentiate between cancer cells at different stages of tumorigenesis using a nanoclay-based three-dimensional (3D) bone mimetic in vitro model that mimics prostate cancer bone metastasis. A comprehensive study comparing the classification of as received prostate cancer cells in a two-dimensional (2D) model and cancer cells in a 3D bone mimetic environment was performed over various time intervals using principal component analysis (PCA). Our results showed distinctive spectral differences in Raman imaging between prostate cancer cells and the cells cultured in 3D bone mimetic scaffolds, particularly at 1002, 1261, 1444, and 1654 cm −1 , which primarily contain proteins and lipids signals. Raman maps capture sub-cellular responses with the progression of tumor cells into metastasis. Raman feature extraction via cluster analysis allows for the identification of specific cellular constituents in the images. For the first time, this work demonstrates a promising potential of Raman imaging, PCA, and cluster analysis to discriminate between cancer cells at different stages of metastatic tumorigenesis.
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Extracellular Mechanical Stimuli Alters the Metastatic Progression of Prostate Cancer Cells within 3D Tissue Matrix
This study aimed to understand extracellular mechanical stimuli’s effect on prostate cancer cells’ metastatic progression within a three-dimensional (3D) bone-like microenvironment. In this study, a mechanical loading platform, EQUicycler, has been employed to create physiologically relevant static and cyclic mechanical stimuli to a prostate cancer cell (PC-3)-embedded 3D tissue matrix. Three mechanical stimuli conditions were applied: control (no loading), cyclic (1% strain at 1 Hz), and static mechanical stimuli (1% strain). The changes in prostate cancer cells’ cytoskeletal reorganization, polarity (elongation index), proliferation, expression level of N-Cadherin (metastasis-associated gene), and migratory potential within the 3D collagen structures were assessed upon mechanical stimuli. The results have shown that static mechanical stimuli increased the metastasis progression factors, including cell elongation (p < 0.001), cellular F-actin accumulation (p < 0.001), actin polymerization (p < 0.001), N-Cadherin gene expression, and invasion capacity of PC-3 cells within a bone-like microenvironment compared to its cyclic and control loading counterparts. This study established a novel system for studying metastatic cancer cells within bone and enables the creation of biomimetic in vitro models for cancer research and mechanobiology.
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- Award ID(s):
- 2213958
- PAR ID:
- 10540975
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Bioengineering
- Volume:
- 10
- Issue:
- 11
- ISSN:
- 2306-5354
- Page Range / eLocation ID:
- 1271
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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