Abstract 4800: Heterogeneity of cancer associated fibroblasts in non-small cell lung cancer is defined by the level of collagen gel contraction activity
Authors: Navab Roya , Hao Jing , Sakashita Shingo , Wang Dennis , Pintilier Melania , Wang Yuhui , Zhu Chang-Qi , Venkat Kalpana , Jurisica Igor , Tsao Ming-Sound 
Published: May 2015

Background: Cancer associated fibroblasts (CAFs) are well known to strongly influence tumor development, progression and metastasis. Their characteristics and prognostic gene signature in non-small cell lung cancer (NSCLC) patients have been recognized. However, the functional heterogeneity of CAFs between patients and their genetic basis were far less known. The results revealed two functionally and also genetic distinct subgroups of CAFs which were closely related to the degree of tumor desmoplasia and also prognostic of survival in NSCLC patients.

Methods: 28 independent lung cancer resection specimens were used to establish primary cultures of CAFs and noncancer fibroblasts from the corresponding nonneoplastic lung parenchyma. We applied collagen gel contraction and xCELLigence Real-Time Cell Analysis of proliferation and in vivo tumorigenicity for measuring the CAF activity. To assess the grading of desmoplasia, the percentage of desmoplasia in total tumor stroma was used to define high desmoplasia (HD) versus low desmoplasia (LD). Microarray data on RNA extracted from contracted gels following 8 hours incubation was performed using Illumina Human HT-12v4 Bead Chips array and was preprocessed and normalized using RMA and values were log2 transformed.

Results: We have identified that CAF activity depends on higher ability to contract collagen gel, increased cell proliferation and tumor growth. Using microarray gene expression analysis of the 24 CAF cell lines (12 CAFs-HD versus 12 CAFs-LD), we observed high correlation of differential gene expression in extreme CAF-HD to tumor stroma while we found a high correlation between differential gene expression in extreme CAF-LD to normal lung. We were also able to validate our previous published subset of 11 genes (13 probe sets) in CAFs-HD versus CAFs-LD. To study the degree of desmoplasia and outcome, we used MedBio data set containing 181 records. We observed that desmoplasia appears to be associated with the time to relapse in univariable analysis. The association was far stronger in the adenocarcioma group with significance for both univariable and multivariable analysis.

Conclusion: In this study, we provided the direct and robust evidence of functional heterogeneity of CAFs in NSCLC patients and first showed that CAFs from tumor with severe desmoplasia had higher gel contraction activity, proliferation rate and enhanced tumor growth. Furthermore, we developed desmoplasia-specific gene signature that could subgroup CAFs and contribute to their functional heterogeneity which would also allow us to discriminate among patients who would more likely benefit from tumor stroma targeting therapies in the future.

Citation Format: Roya Navab, Jing Hao, Shingo Sakashita, Dennis Wang, Melania Pintilier, Yuhui Wang, Chang-Qi Zhu, Kalpana Venkat, Igor Jurisica, Ming-Sound Tsao. Heterogeneity of cancer associated fibroblasts in non-small cell lung cancer is defined by the level of collagen gel contraction activity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4800. doi:10.1158/1538-7445.AM2014-4800