Background: Over a century ago, Virchow proposed that cancer represents a chronically inflamed, poorly healing wound. Normal wound healing is represented by a transitory phase of inflammation, followed by a pro-resolution phase, with prostaglandin (PGE2/PGD2)-induced 'lipid class switching' producing inflammation-quenching lipoxins (LXA4, LXB4).
Objective: We explored if lipid dysregulation in colorectal cancers (CRCs) is driven by a failure to resolve inflammation.
Colorectal cancer (CRC) is the second leading cause of cancer death in the United States. The RAS pathway is activated in more than 55% of CRC and has been targeted for therapeutic intervention with MEK inhibitors. Unfortunately, many patients have de novo resistance, or can develop resistance to this new class of drugs.
View Article and Find Full Text PDFRecently, it was suggested that consensus molecular subtyping (CMS) may aide in predicting response to EGFR inhibitor (cetuximab) therapies. We recently identified that and as two tumor suppressor genes, when mutated, may enhance cetuximab sensitivity and may represent easily measured biomarkers in tumors or blood. Our study aimed to use and mutations (AP) to refine the CMS classification to better predict responses to cetuximab.
View Article and Find Full Text PDFVitamin E δ-tocotrienol has been shown to have antitumor activity, but the precise molecular mechanism by which it inhibits the proliferation of cancer cells remains unclear. Here, we demonstrated that δ-tocotrienol exerted significant cell growth inhibition pancreatic ductal cancer (PDCA) cells without affecting normal human pancreatic ductal epithelial cell growth. We also showed that δ-tocotrienol-induced growth inhibition occurred concomitantly with G(1) cell-cycle arrest and increased p27(Kip1) nuclear accumulation.
View Article and Find Full Text PDFWe describe the design of a potent and selective peptidomimetic inhibitor of geranylgeranyltransferase I (GGTI), GGTI-2418, and its methyl ester GGTI-2417, which increases the levels of the cyclin-dependent kinase (Cdk) inhibitor p27(Kip1) and induces breast tumor regression in vivo. Experiments with p27(Kip1) small interfering RNA in breast cancer cells and p27(Kip1) null murine embryonic fibroblasts demonstrate that the ability of GGTI-2417 to induce cell death requires p27(Kip1). GGTI-2417 inhibits the Cdk2-mediated phosphorylation of p27(Kip1) at Thr187 and accumulates p27(Kip1) in the nucleus.
View Article and Find Full Text PDFGastrointestinal stromal tumors, the most common mesenchymal tumors of the gastrointestinal tract, are characterized by strong expression of c-Kit protein. Recently, it has been shown that gastrointestinal stromal tumors may also contain alterations of genes involved in the regulation of cell cycle. In this study, we evaluate the prevalence and clinical significance of cyclin D1 and D3, Ki-67, p27, and retinoblastoma protein expression in a group of 50 human gastrointestinal stromal tumors selected from the files of the Moffitt Cancer Center.
View Article and Find Full Text PDFThe primitive neuroectodermal tumor (PNET)/Ewing family of tumors (EFT) and desmoplastic small round cell tumor (DSRCT) portend a grave prognosis. Ongoing research in similar neurocrest-derived neoplasms has implicated both the muscarinic acetylcholine receptor (mAChR) and nicotinic acetylcholine receptor (nAChR) in the pathogenesis of these neoplasms. Acetylcholine has been reported to impart a modulatory effect on chemotaxis and proliferation, an effect ameliorated by anticholinergic drugs.
View Article and Find Full Text PDFSrc kinase has been linked as a causative agent in the progression of a number of cancers including colon, breast, lung and melanoma. Src protein and activity levels are increased in colorectal cancer and liver metastases arising secondary to colon cancer. However, although Src protein is increased in colon cancer as early as the adenomatous polyp stage, a role for Src in carcinogenesis has not been established.
View Article and Find Full Text PDFBackground: The binding of cyclins to cyclin-dependent kinases regulates cell proliferation. Overexpression of cyclins is believed to deregulate the cell cycle in human tumors. Here the expression of G1 cyclins D1 and D3, and of Ki-67 in a variety of bone and soft tissue sarcomas was assessed as compared to adjacent normal tissue and to a subset of leiomyomas.
View Article and Find Full Text PDFNormal cellular functions of hamartin and tuberin, encoded by the TSC1 and TSC2 tumor suppressor genes, are closely related to their direct interactions. However, the regulation of the hamartin-tuberin complex in the context of the physiologic role as tumor suppressor genes has not been documented. Here we show that insulin or insulin growth factor (IGF) 1 stimulates phosphorylation of tuberin, which is inhibited by the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 but not by the mitogen-activated protein kinase inhibitor PD98059.
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