Somatic mutational profiles of stage II and III gastric cancer according to tumor microenvironment immune type
GENES CHROMOSOMES & CANCER
Authors: Koh, Jiwon; Nam, Soo Kyung; Roh, Hanseong; Kim, Jonghyuk; Lee, Byung-Chul; Kim, Jin Won; Ahn, Sang-Hoon; Park, Do Joong; Kim, Hyung-Ho; Park, Kyoung Un; Chung, Jin Haeng; Kim, Woo Ho; Lee, Hye Seung
Abstract
We aimed to determine somatic mutational profiles of stage II/III gastric cancers (GCs) according to their tumor microenvironment immune types (TMITs), which classify cancer based on co-assessment of PD-L1 expression and CD8(+) tumor infiltrating lymphocytes. Eighty patients with stage II/III GC were classified as follows: TMIT I (PD-L1(+)/CD8(High)), TMIT II (PD-L1(-)/CD8(Low)), TMIT III (PD-L1(+)/CD8(Low)), and TMIT IV (PD-L1(-)/CD8(High)). Deep targeted sequencing using a panel of 170 cancer-related genes was performed on an Illumina HiSeq-2500 system. Most frequently mutated genes included GNAQ (41.3%), TP53 (38.8%), CREBBP (35.0%), and MAP3K1 (35.0%). PIK3CA mutations were observed more frequently in TMIT I (45.8%) and III (66.7%), than in II (12.0%) and IV (8.0%). Other genes with enriched mutations within TMIT I included ATM (33.3%), BRCA2 (33.3%), MAP3K4 (29.2%), and FLT4 (25.0%). FGFR3, MAP3K1, and RUNX1 mutations were more frequently found in TMIT II. TMIT III had a unique somatic mutation profile harboring enriched mutations of histone modifiers including CREBBP and KMT2A, and we found FGFR2 amplification exclusively within TMIT IV. Fuzzy clustering analysis based on somatic mutation frequencies identified a hypermutated group (cluster 1) and a hypomutated group (cluster 2). Cluster 1 had significant associations with TMIT I, EBV+ GCs, and MSI-H GCs (P = .023, .014, and .004), and had better overall survival (P = .057) than Cluster 2. TMIT I, EBV+, and MSI-H GCs were estimated to have greater tumor mutational burden (P = .023, .003, and .015). By analyzing somatic mutation profiles according to TMIT classification, we identified TMIT-specific genetic alterations that provide clues for biological linkage between GC genetics and microenvironment.
Genistein suppresses FLT4 and inhibits human colorectal cancer metastasis
ONCOTARGET
Authors: Xiao, Xiao; Liu, Zhiguo; Wang, Rui; Wang, Jiayin; Zhang, Song; Cai, Xiqiang; Wu, Kaichun; Bergan, Raymond C.; Xu, Li; Fan, Daiming
Abstract
Dietary consumption of genistein, found in soy, has been associated with a potentially protective role in colorectal cancer (CRC) development and progression. Herein we demonstrate that genistein will inhibit human CRC cell invasion and migration, that it does so at non-cytotoxic concentrations and we demonstrate this in multiple human CRC cell lines. After orthotopic implantation of human CRC tumors into mice, oral genistein did not inhibit tumor growth, but did inhibit distant metastasis formation, and was non-toxic to mice. Using a qPCR array, we screened for genistein-induced changes in gene expression, followed by Western blot confirmation, demonstrating that genistein downregulated matrix metalloproteinase 2 and Fms-Related Tyrosine Kinase 4 (FLT4; vascular endothelial growth factor receptor 3). After demonstrating that genistein suppressed neo-angiogenesis in mouse tumors, we examined FLT4 expression in primary CRC and adjacent normal colonic tissue from 60 human subjects, demonstrating that increased FLT4 significantly correlates with increased stage and decreased survival. In summary, we demonstrate for the first time that genistein inhibits human CRC metastasis at dietary, non-toxic, doses. FLT4 is identified as a marker of metastatic disease, and as a response marker for small molecule therapeutics that inhibit CRC metastasis.