Properties Of Lung Cancer Cells Research Articles

Suppression of Type 1 Insulin-like Growth Factor Receptor Expression by Small Interfering RNA Inhibits A549 Human Lung Cancer Cell Invasion <italic>in vitro</italic> and Metastasis in Xenograft Nude Mice

Cancer invasion and metastasis, involving a variety of pathological processes and cytophysiological changes, contribute to the high mortality of lung cancer. The type 1 insulin-like growth factor receptor (IGF-1R), associated with cancer progression and invasion, is a potential anti-invasion and anti-metastasis target in lung cancer. To inhibit the invasive properties of lung cancer cells, we successfully down-regulated IGF-1R gene expression in A549 human lung cancer cells by small interfering RNA (siRNA) technology, and evaluated its effects on invasion-related gene expression, tumor cell in vitro invasion, and metastasis in xenograft nude mice. A549 cells transfected with a plasmid expressing hairpin siRNA for IGF-1R showed a significantly decreased IGF-1R expression at the mRNA level as well as the protein level. In biological assays, transfected A549 cells showed a significant reduction of cell-matrix adhesion, migration and invasion. Consistent with these results, we found that down-regulation of IGR-1R concomitantly accompanied by a large reduction in invasion-related gene expressions, including MMP-2, MMP-9, u-PA, and IGF-1R specific downstream p-Akt. Direct tail vein injections of plasmid expressing hairpin siRNA for IGF-1R significantly inhibited the formation of lung metastases in nude mice. Our results showed the therapeutic potential of siRNA as a method for gene therapy in inhibiting lung cancer invasion and metastasis.

The effect of vinblastine on the viscoelastic properties of lung cancer cells

To explore the effect of vinblastine on the viscoelastic properties of highmetastatic human giant cell carcinoma cells ( PC) and low metastatic adenocarcinoma cells (PAa) of the lung and its biomechanical mechanisms. The viscoelastic properties of PG and PAa cells and their changes after treated with vinblastine (VCR, 0. 10-2. 00Lg/ml) were detected by micropipette aspiration technique. Viscoelasticity was analyzed by the special three-element standard linear solid model. Before treated with VCR, the elastic coefficients K1 and K2 as well as viscous coefficient L of PAa were significantly higher than those of PG cells. The values of K1, K2 and L of PAa cells decreased along with the increase of VCR concentration. However, the viscoelastic coefficient values in PG cells decreased when the VCR concentration was lower than 1. 00Lg/ml and then turned to increase as concentration of VCR went on increasing. The microtubules and microfilaments were sparse random in the PAa cells and diminished in PG cells. After treated with VCR, they were cut down seriously in PAa cells, and manifestations of mitotic arrest of cell cycle increased unusually in PG cells. The cytoskeleton structure component changes are related to the viscoelasticity of the tumor cells. The anti-neoplasm actions of cytoskeleton interferents such as VCR might be realized by mainly regulating the message of tumor cells growth and differentiation.

Biology of lung cancer

While the overall survival of patients with lung cancer has remained relatively unchanged over the past decade, there have been major advances in our understanding of the biology of small cell and non-small cell lung cancer through the study of lung cancer cell lines. Surface molecules associated with lung cancer have been identified and their molecular structure and function are being elucidated. Growth factors which stimulate the lung cancer cells in an autocrine fashion have been identified. Genetic changes of lung cancer cells have been defined on a chromosomal and a molecular level. This review summarizes many biologic properties of lung cancer cells that have been described in the literature.