[Effects of MSP on Cell Cycle and EMT of Non-Small Cell Lung Cancer PC14].

OBJECTIVE: To study the effect of macrophage stimulating protein (MSP) on the cell cycle of non-small cell lung cancer PC14 cells without expression of recepteur d'originenanta (RON) and MSP,and analyse its effect on PC14's epithelial mesenchymal transition (EMT) capacity. METHODS: Vitro culture PC14 (blank control),PC14-Mst1-pEGFP-N1 (stablely expressed MSP) and PC14-pEGFP-N1. Cell cycles were detected by flow cytometry and the gaps between cells during growth were measured by transmission electron microscope (TEM); RT-PCR and Western blot were used to figure out the shifts of EMT related gene expression in PC14-Mst1-pEGFP-N1 cells. RESULTS: Compared with the PC14 group and PC14-pEGFP-N1 group,PC14-Mst1-pEGFP-N1 population of G1/G0 phase were significantly increased while S and G2/M phase were significantly reduced;The gaps between PC14-Mst1-pEGFP-N1 cells decreased; RT-PCR and Western blot showed that mRNA and protein levels of E-cadherin of PC14-Mst1-pEGFP-N1 were significantly higher than that of PC14,but mRNA and protein levels of Vimentin were significantly lower. CONCLUSION: MSP may affect the cell cycle of PC14 and inhibit its EMT procedure by regulating the expression of related proteins including E-cadherin and Vimentin when RON was not expressed.

[Effects of Msp on the Proliferation, Migration and Invasion of Human Non-small Cell Lung Cancer Cells].

OBJECTIVES: To determine the effects of macrophage stimulating protein (Msp) on the proliferation, migration and invasion of human non-small cell lung cancer cells PC14. METHODS: The eukaryotic expression vector for st1was constructed and transfected into Msp(-)and RON(-)human non-small cell lung cancer cells PC14. The expression of st1mRNA in PC14 cells was observed by RT-PCR. The expression levels of Msp protein in PC14, PC14-st1-pEGFP-N1 and PC14-pEGFP-N1 groups as well as the expression of RON in PC14 and SKBR-3 cells were detected by Western blot. RAW264.7 (mouse monocyte macrophage) and SKBR-3 cells were cultured in the supernatant of cells(PC14, PC14-st1-pEGFP-N1and PC14-pEGFP-N1 groups)and tested with Transwell microporous membrane, through which the biologic activity of Msp was evaluated by calculating the cell number migrated. The proliferation of PC14 was measured by MTT assay. The capabilities of PC14 to migrate and invade were measured by Transwell chamber and Matrigel invasion tests, respectively. RESULTS: The expressions of mRNA and protein of Mst1 in PC14 were stable after transfection with Mst1. Msp (PC14-st1 -pEGFP-N1 group) promoted the migration of RON (+) cells (SKBR-3 and RAW264.7). Compared with PC14 and PC14-pEGFP-N1 groups, the proliferation, migration and invasion of PC14 cells in PC14-st1 -pEGFP-N1 group were inhibited significantly. CONCLUSIONS: Msp can promote the migration of RON (+) cancer cells in paracrine secretion manner and inhibit the proliferation, migration and invasion of human non-small cell lung cancer cells PC14 in an unknown way.

A multiple-dose pharmacokinetics of polyethylene glycol recombinant human interleukin-6 (PEG-rhIL-6) in rats.

Radiation therapy has been widely applied in cancer treatment. However, it often causes thrombocytopenia (deficiency of white blood cells) as an adverse effect. Recombinant human interleukin-6 (rhIL-6) has been found to be a very effective way against this thrombocytopenia, but IL-6 has low stability in blood, which reduces its efficacy. To increases the stability and half-life of rhIL-6, it was modified by polyethylene glycol (PEG). The pharmacokinetics and the tissue distribution of PEG-rhIL-6 labeled with (125)I were examined after subcutaneous injection in rats. The pharmacokinetic pattern of PEG-rhIL-6 was defined with linear-kinetics, and we fitted a one-compartment model with half-lives of 10.44-11.37 h (absorption, t(1/2Ka)) and 19.77-21.53 h (elimination, t(1/2Ke)), and peak concentrations at 20.51-21.96 h (t(peak)) in rats. Half-lives and t(peak) of PEG-rhIL-6 were longer than those of rhIL-6 previously reported. In the present study, for deposition of PEG-rhIL-6 in rats, the tissue distribution examination showed that blood was the major organ involved, rather than liver. However, as to the elimination of PEG-rhIL-6, the major organ was the kidney. The excretion fraction of the injection dose recovered from urine was 23.32% at 192 h after subcutaneous administration. Less than 6% of PEG-rhIL-6 was eliminated via the feces at 192 h. These results indicate that PEG-rhIL-6 is a good candidate drug formulation for patients with cancer.

[Pharmacokinetics of PEG recombinant human interleukin-6 in rats].

OBJECTIVE: To study the pharmacokinetics and tissue distribution of PEG-rhIL-6 in rats after a single dose administration. METHODS: Pharmacokinetics and distribution of PEG-rhIL-6 in rats were studied by 125I isotope tracing method. Pharmacokinetic analysis was performed using 3P97 computer software. RESULTS: PEG-rhIL-6 declined in one-compartment model with half-lives of 10.44-11.37 h for t1/2 Ka, 19.77-21.53 h for t1/2 Ke and 20.51-21.96 h for T(pcak), respectively. PEG-rhIL-6 was mainly distributed in blood and excreted via urine. CONCLUSION: The half-lives of PEG-rhIL-6 are prolonged after being modified by PEG.