Fig. 3.

CSE and B[α]P increased levels of JAK2/STAT3 pathway expression and induced increases OPN expression and MSC recruitment in human lung cancer cells. (A) A Gene Set Enrichment Analysis (GSEA)-based pathway analysis included RAS, ERK, EGF and p38 MAPK gene sets associated with lung cancer in smokers and nonsmokers obtained from the BioCarta database. (B) Western blot analysis examined levels of MAPK (ERK, JNK, p38), H-Ras, β-actin, JAK2 and STAT3 phosphorylation in A549-L cells. The graphs demonstrate densitometric analysis of p-p38/p38, p-ERK/ERK, p-JNK/JNK, H-Ras/β-actin, p-JAK2/JAK2 and p-STAT3/STAT3. (C) A549-L cells were incubated with a JAK2 inhibitor for 24 h. Western blot examined levels of STAT3 phosphorylation. A549-L cells were incubated with JAK2/STAT3 inhibitors or JAK2/STAT3 siRNAs for 24 h. Densitometric analysis of protein expression was normalized to β-actin. (D-G) Levels of OPN expression were examined by qRT-PCR and ELISA assays. (H) The Transwell assay examined MSC recruitment in CM collected from A549-L cells after 24 h of incubation. (I) The adhesion assay examined levels of MSC adhesion with A549-L cells after 24 h of incubation. All results are expressed as the mean ± SD of three independent samples. *p < 0.05 compared with levels of the parental group; #p < 0.05 compared with 1 μM B[α]P or 1% CSE treatment.