Abstract 5056: Up-regulated expression and activation of invadopodia-associated proteases in esophageal squamous cell carcinoma (ESCC).
Authors: Augoff Katarzyna , Hryniewicz-Jankowska Anita , Tabola Renata , Czapla Leszek , Szelachowski Piotr , Grabowski Krzysztof , Sikorski Aleksander F. 
Published: August 2014

To invade adjacent tissues, cancer cells form special membrane protrusions with high proteolytic activity, named invadopodia. To better understand the role of invadopodia-associated proteolytic systems in the growth of esophageal cancer, we studied the expression of two serine proteases, FAP-alpha and DPPIV, and three metalloproteinases, MMP-2, MMP-9 and MT1-MMP, in a primary ESCC. The enzyme profile was evaluated in relation to the synthesis of cortactin as an important control factor in invadopodia formation and function. The expression and activity of proteases and cortactin in cancer tissues paired with non-cancer tissues were analyzed by RT-PCR, WB and zymography. Tissue samples were obtained from 24 patients who were undergoing surgical resection for esophageal carcinoma. All the tumors had been classified as ESCC and diagnosed as T3 or T4, N1-N3, and M0-M1 according to the TNM classification. The non-cancer tissue samples were taken from the distal area (5-10 cm from the macroscopic changes) and confirmed in histological examinations to be R0. We found an average 3-fold increase in DPPIV expression and an average five-fold higher level of FAP-alpha expression in ESCC over the control tissues. Up-regulation of DPPIV positively correlates with the FAP-alpha expression ratio. FAP-alpha transcripts and DPPIV mRNAs were observed in all the analyzed cancer and non-cancer tissue samples. We found a much higher level of the active MT1-MMP form in cancers relative to paired non-cancer tissues. The correlation between the level of MT1-MMP active form and MMP-2 activity observed in this study shows a tight connection between the two enzymes. We observed enhanced synthesis and activation of both MMP-2 and MMP-9 in cancer tissues. The cancer to normal ratios of the two active gelatinases correlated positively with the expression levels of both serine proteases. We examined the levels of CTTN in the cancer and non-cancer tissues of esophagus in order to find out if CTTN expression is associated with the expression and/or activity of invadopodia proteases. The increased level of CTTN was identified in 35% of ESCC tissues but the differences between groups were not statistically significant. No significant correlation was found between CTTN expression level and any other factors evaluated in our study.

In conclusion, we showed that invadopodia-associated proteases, including FAP-alpha, DPPIV, MT1-MMP, MMP-2 and MMP-9, are significantly up-regulated in ESCC and that it might contribute to a more aggressive esophageal cancer. The presence of FAP-alpha in the cancer-free surgical margin suggests that alterations in the stromal environment may extend much father into surrounding tumor tissues than is usually considered.

Citation Format: Katarzyna Augoff, Anita Hryniewicz-Jankowska, Renata Tabola, Leszek Czapla, Piotr Szelachowski, Krzysztof Grabowski, Aleksander F. Sikorski. Up-regulated expression and activation of invadopodia-associated proteases in esophageal squamous cell carcinoma (ESCC). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5056. doi:10.1158/1538-7445.AM2013-5056