Biophysical Society Thematic Meeting

Mechanobiology of Disease

Poster Abstracts

28-POS

Board 28

Heterogeneity of Elastic Modulus in Metastatic and Non-Metastatic Retinoblastoma(Rb)

Cells and Its Correlation with Cluster Size

Narayanan Janakiraman

1,3

, Kong Fang

.Lim Chwee Tech

4,3,2

Vision Research Foundation, Chennai, Tamilnadu, India,

Singapore MIT Alliance of Research

and Technology, Infectious Disease IRG, singapore, Singapore,

Mechanobiology Institute

(MBI),, Singapore, Singapore,

Department of Biomedical Engineering, National University of

Singapore, Singapore, Singapore.

Retinoblastoma is the eye cancer in children. The stage dependent mechanical behavior of the

tumor cell can alter the course of tumor metastasis. Objective: we aim to understand the

mechanical properties of retinoblastoma tumor cells in two different (Metastatic and Non-

Metastatic) stages. Method: Young’s modulus of WERI-Rb1 (non-metastatic) and RBC NCC 51

(metastatic) retinoblastoma cells were measured using atomic force microscopy (AFM).

Measurements were carried out using AFM cantilevers with a bead tip radius of 4.5 micron (and

spring constant of 0.02N/m). Results: The Young’s moduli of cells were acquired by fitting the

force indentation curves with Hertz’s contact model. The average young’s moduli of metastatic

and non-metastatic cells was found to be 128pa±60 (Mean standard deviation) and 149pa±90

(Mean standard deviation) respectively. However, retinoblastoma tumor cells tend to form

various size clusters. Singlet, doublet and cluster of more than three cells showed Young’s

modulus in a decreasing order. Metastatic cluster (more than 7 cells) (NCC) were found to have

a lower Young’s modulus on average, i.e., 85Pa±11pa (mean ± stand deviation), than non-

metastatic cluster cells (WERI-Rb1), i.e., 191Pa±117pa (mean ± standard deviation).

Conclusion: The heterogeneity in Young's modulus of cells with different cluster size reveals

that the heterogeneous population of tumor cells can have possibility of sub stages where the

transition between non-metastatic to metastatic stages can occur.