mRNA expression of signal transducer and activator of transcription (STAT5), disheveled-3 (Dvl-3) and dicer in early-stage non-small-cell lung cancer (NSCLC)
17038 Background: STAT5 plays a role in angiogenesis and metastasis. Activation of STAT5 occurs through dysregulation of growth factor receptor tyrosine kinases (TK) (including EGFR TK mutations), non-receptor TKs or Janus kinases. Dvl-3, a critical mediator of the Wingless-type (Wnt) signaling pathway, contributes to self-renewal of stem cells. Dicer has a key role in processing microRNAs required for stem cell regulation. We assessed mRNA expression of STAT5, Dvl-3 and Dicer in early-stage NSCLC. Methods: cDNA was derived from paraffin-embedded primary tumors of 47 surgically resected, early-stage NSCLC patients. Real-time quantitative reverse transcriptase PCR was used to measure STAT5, Dvl-3 and Dicer mRNA levels relative to the internal reference gene β-actin. Results: Median expression levels were: STAT5, 0.66 (0.15–6.03); Dvl-3, 3.69 (1.02–25.83); Dicer, 4.53 (1.22–21.96). STAT5 levels for squamous cell carcinoma (SCC) were 0.57 vs 0.89 for non-SCC (P=0.01), while Dicer levels were higher in SCC (4.25) than in non-SCC (2.60) (P = 0.01). A strong correlation between the levels of Dvl-3 and Dicer was found (rho = 0.49; P < 0.001). 90% of females had low Dicer mRNA levels (P = 0.01). No other correlation between mRNA levels and patient characteristics was found. Conclusions: High levels of Dvl-3 are associated with SCC. The close correlation between Dvl-3 and Dicer levels may indicate that Dicer could process a class of microRNA that activates the Wnt pathway. In non-SCC, overexpression of STAT5 could be involved in tumor angiogenesis. These 3 transcripts could be potential predictors of metastasis and ideal targets for individualized treatment. No significant financial relationships to disclose.