In surgical operation of the non-small cell lung cancer (NSCLC),the resection of lymph node involvement is highly correlated with the prognosis of NSCLC patients.The precise estimation of localized lymph node involved and the determination of relevant pattern of lymphadenectomy are the significant predictors for the prognosis and postoperative treatment in NSCLC patients.Therefore to identify the lymph node metastasis earlier has more important significance for tumor clinical staging and making therapeutic schedule.In recent years,the value of sentinel lymph node (SIN) has attracted more and more researchers attention in detecting the occult lymph node micrometastases and surgical staging.

OBJECTIVETo establish a model bearing human lung cancer xenograft with bone metastasis in mice with normal immune function.

METHODSForty female C57BL/6J mice were randomly allocated into 4 equal groups, including a control group and 3 immunosuppression groups treated with low, moderate, and high doses of dexamethasone (50, 100, and 150 mg, respectively). Four days after immune suppression, the mice were subjected to percutaneous injection of1.0×10(9) L(-1) A549 cells into the tibial plateau, and the bone defects were assessed radiographically 28 days after modeling. HE staining and immunohistochemical staining were used to examine the tumor tissues and bone tissue damages.

RESULTSIn each of the 4 groups one mouse died during tumor cell injection. Only 1 mouse showed tumor formation in low-dose immunosuppression group, as compared to 7 and 4 in moderate- and high-dose immunosuppression groups. X-ray and microCT scan showed significant tibial bone destruction in moderate- and high-dose groups. The moderate- and high-dose groups showed similar ALP activities but both were significantly higher than those in the other two groups (P<0.05).

CONCLUSIONImmunosuppression with a moderate dose of dexamethasone results in longer survival time of the human lung cancer xenograft-bearing model mice as well as a higher tumor formation rate.

Animals ; Bone Neoplasms ; secondary ; Cell Line, Tumor ; Dexamethasone ; pharmacology ; Disease Models, Animal ; Female ; Humans ; Immunosuppression ; Lung Neoplasms ; pathology ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation