Gene expression profile in the activation of subperitoneal fibroblasts reflects prognosis of patients with colon cancer

Abstract

Tumors can create a heterogenetic tumor microenvironment. We recently identified the pathologically unique cancer microenvironment formed by peritoneal invasion (CMPI), and revealed that subperitoneal fibroblasts (SPFs) within peritoneal tissue play a crucial role in tumor progression through their interaction with cancer cells. Therefore, the genes in SPFs altered by cancer stimulation may include some biologically important factors associated with patient prognosis. In this study, we aimed to identify new biomarkers using genes specifically upregulated in SPFs by cancer-cell-conditioned medium (CCCM) stimulation (SPFs CCCM response genes; SCR genes) in colon cancer (CC). We constructed two frameworks using SCR gene data: a publicly released microarray dataset, and validation cases with freshly frozen CC samples to identify genes related to short recurrence-free survival (RFS). In the first framework, we selected differentially expressed genes between the high and low SCR gene expression groups. In the second framework, genes significantly related to short RFS were selected by univariate analysis using all SCR genes, and multivariate analysis was performed to select robust genes associated with short RFS. We identified CTGF, CALD1, INHBA and TAGLN in the first framework, and PDLIM5, MAGI1, SPTBN1 and TAGLN in the second framework. Among these seven genes, high expression of three genes (CALD1, TAGLN and SPTBN1) showed a poor prognosis in our validation cases. In a public microarray dataset, SCR gene expression was associated with the expression of ECM component, EMT, and M2-macrophage associated genes, which was concordant with the pathological features of CMPI. Thus, we successfully identified new prognostic factors.In the cancer microenvironment (CME), cancer cells are surrounded by fibroblasts, vessel component cells, inflammatory cells including lymphocytes and macrophages, and the extracellular matrix (ECM) produced by these stromal cells. Fibroblasts were first described in the late 19th century as the nonvascular, nonepithelial and noninflammatory cells of connective tissue, and are the most common of all stromal cells that compose the CME.1 Fibroblasts are also a major source of the ECM component that provides a scaffold for the growth and differentiation of normal epithelial cells, and they are activated in the process of wound healing. 2 However, activated fibroblasts are known to accelerate tumor growth and metastasis. Some growth factors and ECM-remodeling proteases such as matrix metalloproteinases (MMPs) are produced by activated fibroblasts, which contribute to tumor growth and metastasis. [3][4][5] In addition, activated fibroblasts express a-smooth muscle actin (a-SMA) and generate great contractile force. 6 This high contractile activity leads to increased ECM stiffness, which is known to increase the migration activity of cancer cells. 7-10 Thus fibroblasts affect the characteristics of the CME and even cancer progression itself through both a biological and mechanical manner. The gastrointes...

Special cancer microenvironment in human colonic cancer: Concept of cancer microenvironment formed by peritoneal invasion (CMPI) and implication of subperitoneal fibroblast in cancer progression

“…Furthermore, using global gene expression analysis, we elucidated orchestrated regulation of SPFs activation, M2 macrophage, and EMT associated gene expression in human colon cancer tissue. This pattern was similar to morphological features of CMPI (prominent tumor budding, fibrosis, and macrophages), and consistent with the concept of the cancer microenvironment . Successful biomarker research using the gene expression profile of SPFs activated by cancer conditioned medium has also been performed.…”

“…Colorectal cancer prognosis may also be stratified by the activated SPFs genes by cancer conditioned medium stimulation. Therefore, we tried to stratify publicly available microarray data of patients with colon cancer by using expression of SPFs cancer cell conditioned medium response genes (SCR genes) . Interestingly, a biphasic pattern of expression of SCR genes was observed in 226 colorectal cancers from , and was divided into a high SPFs gene signature group (HSGS group) and a low SPFs gene signature group (LSGS group).…”

“…Genes highly expressed in the HSGS group or SCR genes were thought to be enriched in prognostic biomarkers. We constructed frameworks to select candidate markers, and after the validation, new prognostic biomarkers of CALD1 , TAGLN , and SPTBN1 were identified …”

A signature of tumor immune microenvironment genes associated with the prognosis of non‑small cell lung cancer

“…Moreover, CALD1 encodes the caldesmon protein, which is a calmodulin-binding and cytoskeleton-associated protein and regulates cell motility, such as migration and invasion (40,41). It has been suggested that CALD1 may indicate a general splicing event associated with cancer (41,42) and was also identified as a potential prognostic molecular marker for bladder and colon cancer (43)(44)(45).…”

A potential role for CCN2/CTGF in aggressive colorectal cancer

“…A similar role has been proposed for CCN2 based on the observed correlation of CCN2 expression with α-smooth muscle actin expression in ileal carcinoids, an endocrine carcinoma that is extremely rich in fibrosis (Cunningham et al 2010 ). Furthermore, conditioned medium from colon cancer cells can stimulate CCN2 expression in peritoneal fibroblasts (Yokota et al 2016 ).…”