Behavioral remodeling of normal and cancerous epithelial cell lines with differing invasion potential induced by substrate elastic modulus

<p>The micro-environment of cancer cells in the body is mechanically stiffer than that of normal cells. We cultured three breast cell lines of MCF10A-normal, MCF7-noninvasive, and MDA-MB-231-invasive on PDMS substrates with different elastic moduli and different cellular features were examined.Effects of substrate stiffness on cell behavior were evident among all cell lines. Cancerous cells were more sensitive to substrate stiffness for cell behaviors related to cell motility and migration which are necessary for invasion. The invasive cancerous cells were the most motile on substrates with moderate stiffness followed by non-invasive cancerous cells. Gene markers alterations were generally according to the analyzed cell movement parameters. Results suggest that alterations in matrix stiffness may be related to cancer disease and progression.</p

Solution stability curve of SWNT dispersion in SF solution.

<p>It seems that SF as an amphiphilic structure could act as a surfactant agent for dispersing carboxylated-SWNT in stabilized manner.</p

Main Raman band wavenumbers and assignments.

<p>Main Raman band wavenumbers and assignments.</p

Viability of U373 cells (MTT assay).

<p>Less proliferation was observed for cells grown on SWNT containing conduits but not significantly.</p

Raman spectra of: a) pure SF: the amide I band around 1665 cm−1, 1616 cm−1 for Trp, Phe and Tyr, 1240 cm−1 for amide III were observed, b) SF/SWNT: the peak correspondence to skeletal ν (C-C) associated in pure SF is removed, c) SF/SWNT/FN: the β-sheet structure in FN was identified by the characteristically amide I band around 1669 cm−1 and a higher intense band at 1245 cm−1 in the amide III region.

<p>Raman spectra of: a) pure SF: the amide I band around 1665 cm−1, 1616 cm−1 for Trp, Phe and Tyr, 1240 cm−1 for amide III were observed, b) SF/SWNT: the peak correspondence to skeletal ν (C-C) associated in pure SF is removed, c) SF/SWNT/FN: the β-sheet structure in FN was identified by the characteristically amide I band around 1669 cm−1 and a higher intense band at 1245 cm−1 in the amide III region.</p

Cross sections of regenerated nerves taken from types of nerve conduits implanted in rats for 5

<p>a) Normal nerve, b) negative control (Defected sciatic nerve without NGC), c) Defects filled by SF/SWNT conduits, d) Defects filled by SF/SWNT/FN conduits. <b>Wide arrows</b>: myelinated axon. <b>Narrow arrows</b>: Schwann cells.</p

Histological assessment of NGCs after 5

<p>a) Normal nerve, b) negative control (Defected sciatic nerve without NGC), c) Defects filled by SF/SWNT conduits, d) Defects filled by SF/SWNT/FN conduits. <b>Wide </b><b>arrows</b>: myelinated axon. <b>Narrow </b><b>arrows</b>: Schwann cells.</p

DSC thermogram of: a) pure SF, b) Pure SF after methanol treatment, c) SF/SWN substrates.

<p>Incorporating SWNT to the structure of methanol treated SF has a cumulative effect on growing the thermal stability to 288.4°C. A melting point absorption peak in the DSC trace of SF/SWNT in 77.7°C would also indicate the existence of SWNT.</p

Fibronectin bioactivity after 14 days <i>in vitro</i> study.

<p>FN exhibited high bioactivity (about 85%).</p

Cross sections of regenerated nerves taken from types of nerve conduits implanted in rats for 5-100.

<p>a) Normal nerve, b) Defected sciatic nerve without NGC (control group), c) Defects filled by SF/SWNT conduits, d) Defects filled by SF/SWNT/FN conduits. <b>Wide arrows</b>: myelinated axon. <b>Narrow arrows</b>: Schwann cells.</p