ABSTRACT
Mesenchymal stem cells (MSCs) are believed to be a potential vehicle delivering antitumor agents for their tumor-homing capacity, while the underlying mechanism is yet to be explored. The apoptotic ligand TNF-related apoptosis-inducing ligand (TRAIL) has been suggested as a promising candidate for cancer gene therapy owing to its advantage of selectively inducing apoptosis in cancer cells while sparing normal cells. An isoleucine zipper (ISZ) added to the N-terminal of secretable soluble TRAIL (sTRAIL) can generate the trimeric form of TRAIL (ISZ-sTRAIL) and increase its antitumor potential. However, the inefficient delivery and toxicity are still obstacles for its use. In this study, the migration of human umbilical cord mesenchymal stem cells (HUMSCs) to lung cancer was observed through transwell migration assay and animal bioluminescent imaging both in vitro and in vivo. We found that the homing ability of HUMSCs was suppressed after either knocking down the expression of monocyte chemoattractant protein-1(MCP-1) in lung cancer cells or blocking CCR2 expressed on the surface of HUMSCs, indicating the important role of MCP-1/CCR2 axis in the tropism of HUMSCs to lung cancer. Furthermore, we genetically modified HUMSCs to deliver ISZ-sTRAIL to tumor sites specifically. This targeted therapeutic system exhibited promising apoptotic induction and antitumor potential in a xenograft mouse model without obvious side effects. In conclusion, HUMSCs expressing ISZ-sTRAIL might be an efficient therapeutic approach against lung cancer and MCP-1/CCR2 axis is essential for the tumor tropism of HUMSCs.
Subject(s)
Chemokine CCL2/genetics , Lung Neoplasms/drug therapy , Mesenchymal Stem Cells/metabolism , Receptors, CCR2/genetics , TNF-Related Apoptosis-Inducing Ligand/pharmacology , Animals , Blotting, Western , Cell Line, Tumor , Cell Migration Assays , Cell Movement/physiology , Chemokine CCL2/metabolism , Enzyme-Linked Immunosorbent Assay , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Mice , Molecular Targeted Therapy , Real-Time Polymerase Chain Reaction , Receptors, CCR2/metabolism , Umbilical Cord/cytologyABSTRACT
PURPOSES: Osteopontin (OPN), an extracellular matrix-secreted phosphorylated glycoprotein, has been reported overexpressed in many solid tumors. As an important part of lung cancer, the high recurrence of non-small cell lung cancer (NSCLC) also attracted great attention of scientists. METHODS: In this study, we investigated the expression of OPN and the relationship with prognosis of NSCLC patients. We measured the expression of OPN among 163 NSCLC samples by immunohistochemical method and compared the expression of these 28 matched cDNA between tumor and peritumoral tissue by real-time polymerase chain reaction. RESULTS: We demonstrated that the percentages of positive OPN expression is 66.8 % and OPN expression in tumor site was much higher than the tissue adjacent to carcinoma (p = 0.0046). By further analysis, we found that OPN expression was significantly correlated with poor prognosis of NSCLC. Moreover, for early-stage patients, OS and DFS rates of OPN (-) group were significantly higher than OPN (+) group. For advanced-stage patients, OPN expression was only associated with OS rates. CONCLUSIONS: These results suggest that OPN is commonly expressed in NSCLC and may guide the evaluation of prognosis with NSCLC, especially for early-stage patients.
