Heparin co-factor II enhances cell motility and promotes metastasis in non-small cell lung cancer.

Using the Serial Analysis of Gene Expression (SAGE) database from the Cancer Genome Anatomy Project, we identified heparin co-factor II (HCII), which is over-expressed in non-small cell lung cancer (NSCLC). Here, we investigated the clinical significance of HCII and provided molecular evidence to support the suggestion that HCII could enhance cancer metastasis in NSCLC. We found that high HCII expression in tumour tissue was associated with increased cancer recurrence and shorter overall survival times in 75 clinically operable NSCLC patients.

The migration speed of cancer cells influenced by macrophages and myofibroblasts co-cultured in a microfluidic chip.

We employ a microfluidic chip with three culture chambers to investigate the interactions among lung cancer cells, macrophages and myofibroblasts. By mixing the conditioned media of macrophages and myofibroblasts in this chip, we confirm that these two stromal cells have synergistic effects in accelerating the migration of cancer cells. However, as the myofibroblasts are pretreated with the conditioned medium of macrophages, the myofibroblasts' ability to enhance the migration of cancer cells is lowered.

Analysis of the paracrine loop between cancer cells and fibroblasts using a microfluidic chip.

We use a microfluidic cell culture chip equipped with pneumatic microvalves to analyze the paracrine loop between lung cancer cells and fibroblasts. In order to assess the cellular responses in the paracrine loop, we measure the migration speeds of cancer cells and the aspect ratios of fibroblasts which reflect the phenotype of myofibroblasts. With well-controlled interaction sequences between these two types of cells, we verify that the cytokines from cancer cells effectively stimulate the fibroblasts into myofibroblasts.

Three-dimensional tracking and temporal analysis of liposomal transport in live cells using bright-field imaging.

Gold nanoparticles (AuNPs) confined in liposomes of diameters around 200 nm produce strong scattering signal owing to surface plasmon resonance, and therefore bright-field optical tracking of the AuNP-encapsulating liposomes can be conducted in living cells. Using an optical profiling technique called noninterferometric wide-field optical profilometry and a bright-field tracking algorithm, the polynomial-fit Gaussian weight method, we analyze three-dimensional (3D) motion of such liposomes in living fibroblasts. The positioning accuracy in three dimensions is nearly 20 nm.

Label-free quantification of asymmetric cancer-cell filopodium activities in a multi-gradient chip.

We use novel super-resolution bright-field optical microscopy to observe the filopodium activities of human lung cancer cells in a multi-gradient cell culture chip. Temporal variations of the filopodium numbers are measured without fluorescent labelling. By carefully designing the fluidic field inside the culture chip, we establish stable concentration gradients of the injected reagents.

Dynamics of cancer cell filopodia characterized by super-resolution bright-field optical microscopy.

We explore the dynamics of cancer cell filopodia of diameters around 200 nm by using super-resolution bright-field optical microscopy. The high contrast required by the super-resolution image-restoration process is from the nanometer topographic sensitivity of non-interferometric widefield optical profilometry, rather than fluorescence labeling. Because the image-acquisition rate of this bright-field system is 20 frames/min, fast cellular dynamics can be captured and then analyzed.