Involvement of the TGF-beta and beta-Catenin Pathways in Pelvic Lymph Node Metastasis in Early-Stage Cervical Cancer

Purpose: Presence of pelvic lymph node metastases is the main prognostic factor in early-stage cervical cancer patients, primarily treated with surgery. Aim of this study was to identify cellular tumor pathways associated with pelvic lymph node metastasis in early-stage cervical cancer.

Experimental Design: Gene expression profiles (Affymetrix U133 plus 2.0) of 20 patients with negative (N(0)) and 19 with positive lymph nodes (N(+)), were compared with gene sets that represent all 285 presently available pathway signatures. Validation immunostaining of tumors of 274 consecutive early-stage cervical cancer patients was performed for representatives of the identified pathways.

Results: Analysis of 285 pathways resulted in identification of five pathways (TGF-beta, NFAT, ALK, BAD, and PAR1) that were dysregulated in the N(0), and two pathways (beta-catenin and Glycosphingolipid Biosynthesis Neo Lactoseries) in the N(+) group. Class comparison analysis revealed that five of 149 genes that were most significantly differentially expressed between N0 and N(+) tumors (P <0.001) were involved in beta-catenin signaling (TCF4, CTNNAL1, CTNND1/p120, DKK3, and WNT5a). Immunohistochemical validation of two well-known cellular tumor pathways (TGF-beta and beta-catenin) confirmed that the TGF-beta pathway (positivity of Smad4) was related to N(0) (OR:0.20, 95% CI: 0.06-0.66) and the beta-catenin pathway (p120 positivity) to N(+) (OR: 1.79, 95% CI: 1.05-3.05).

Conclusions: Our study provides new, validated insights in the molecular mechanism of lymph node metastasis in cervical cancer. Pathway analysis of the microarray expression profile suggested that the TGF-beta and p120-associated noncanonical beta-catenin pathways are important in pelvic lymph node metastasis in early-stage cervical cancer. Clin Cancer Res; 17(6); 1317-30. (C)2011 AACR.