Colorectal cancers (CRCs) arise from precursor polyps whose cellular origins, molecular heterogeneity, and immunogenic potential may reveal diagnostic and therapeutic insights when analyzed at high resolution. We present a single-cell transcriptomic and imaging atlas of the two most common human colorectal polyps, conventional adenomas and serrated polyps, and their resulting CRC counterparts. Integrative analysis of 128 datasets from 62 participants reveals adenomas arise from WNT-driven expansion of stem cells, while serrated polyps derive from differentiated cells through gastric metaplasia. Metaplasia-associated damage is coupled to a cytotoxic immune microenvironment preceding hypermutation, driven partly by ll

Background-Lymphovascular invasion (LVI) in colorectal cancer (CRC) is considered a strong stage-independent prognostic factor and influences decisions regarding adjuvant chemotherapy in patients with Stage II tumors. However, the degree of interobserver agreement among pathologists for LVI in CRC is largely unknown. This study was undertaken to examine such interobserver variability, and we hypothesized that the use of immunohistochemical markers for vascular and lymphatic channels could improve interobserver agreement.

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Elevated Src expression correlates with malignant potential and metastatic disease in many tumors including pancreas cancer. We sought to characterize the molecular effects of Src kinase inhibition with dasatinib (BMS-354825) a novel, multi-targeted kinase inhibitor that targets Src family kinases, in pancreas ductal adenocarcinoma (PDA). We identified sensitive and resistant PDA cell lines to dasatinib treatment and tested the molecular effects of Src inhibition in vitro and in vivo. We show for the first time that cellular localization of Src expression impacts survival in patients with PDA. Pancreas tumors with increased membranous expression of Src result in decreased survival compared with tumors that have increased cytoplasmic Src expression. Src kinase inhibition with dasatinib markedly inhibits cell proliferation, migration, invasion, cell cycle progression and anchorage independent growth and stimulates apoptosis. This is accompanied by decreased phosphorylation of Src, FAK, paxillin, AKT, STAT3, ERK, JNK and MAPK, as well as decreased cyclinD1 expression in a time and concentration-dependent manner. Furthermore, siRNA to Src results in significant decrease in cell proliferation, invasion and migration of pancreas cancer cells. Dasatinib treatment also inhibits in vivo pancreas tumor growth. Mechanisms of resistance to Src inhibition appear to be related to a lack of inhibition of STAT3 and MAPK signaling. These results establish a mechanistic rationale for Src inhibition with dasatinib as a therapeutic target in the treatment of pancreas cancer and identify potential biomarkers of resistance to Src inhibition.

Esophageal adenocarcinomas (EACs) are poorly responsive to chemotherapeutics. This study aimed to determine the levels of Aurora kinas A (AURKA) and the therapeutic potential of MLN8237, an investigational AURKA inhibitor, alone and in combination with Cisplatin. Using quantitative real time polymerase chain reaction we detected frequent AURKA gene amplification (15/34, 44%) and mRNA overexpression (37/44, 84%) in EACs (p<0.01). Immunohistochemistry analysis demonstrated overexpression of AURKA in more than two-thirds of EACs tissue samples (92/132, 70%) (p<0.001). Using FLO-1, OE19 and OE33 EAC cell lines, with constitutive AURKA overexpression and mutant-p53, we observed inhibition of colony formation with a single treatment of 0.5μM MLN8237 (p<0.05). This effect was further enhanced in combination with 2.5μM Cisplatin (p<0.001). 24hrs after treatment with the MLN8237 or MLN8237 and Cisplatin, cell cycle analyses demonstrated a sharp increase in the percentage of polyploid cells (p<0.001). This was followed by an increase in the percentage of cells in the sub-G1-phase at 72hrs, concordant with the occurrence of cell death (p<0.001). Western blot analysis demonstrated higher induction of TAp73β, PUMA, NOXA, cleaved caspase 3 and cleaved PARP with the combined treatment, as compared to a single agent treatment. Using xenograft models, we demonstrated an enhanced anti-tumor role for the MLN8237 and Cisplatin combination, as compared to single agent treatments (p<0.001). In conclusion, this study demonstrates frequent overexpression of AURKA and suggests that MLN8237 could be an effective anti-tumor agent, which can be combined with CDDP for a better therapeutic outcome in EACs.