Colorectal cancer(CRC) is the third most common cancer in men and the second most common cancer in women,worldwide. In the early stages of the disease, biomarkers predicting early relapse would improve survival rates....Colorectal cancer(CRC) is the third most common cancer in men and the second most common cancer in women,worldwide. In the early stages of the disease, biomarkers predicting early relapse would improve survival rates.In metastatic patients, the use of predictive biomarkers could potentially result in more personalized treatments and better outcomes. The CXC family of chemokines(CXCL1 to 17) are small(8 to 10 kDa) secreted proteins that attract neutrophils and lymphocytes. These chemokines signal through chemokine receptors(CXCR) 1 to 8.Several studies have reported that these chemokines and receptors have a role in either the promotion or inhibition of cancer, depending on their capacity to suppress or stimulate the action of the immune system, respectively.In general terms, activation of the CXCR1/CXCR2 pathway or the CXCR4/CXCR7 pathway is associated with tumor aggressiveness and poor prognosis; therefore,the specific inhibition of these receptors is a possible therapeutic strategy. On the other hand, the lesser known CXCR3 and CXCR5 axes are generally considered to be tumor suppressor signaling pathways, and their stimulation has been suggested as a way to fight cancer.These pathways have been studied in tumor tissues(using immunohistochemistry or measuring mRNA levels)or serum [using enzyme-linked immuno sorbent assay(ELISA) or multiplexing techniques], among other sample types. Common variants in genes encoding for the CXC chemokines have also been investigated as possible biomarkers of the disease. This review summarizes themost recent findings on the role of CXC chemokines and their receptors in CRC and discusses their possible value as prognostic or predictive biomarkers as well as the possibility of targeting them as a therapeutic strategy.展开更多
AIM: To investigate the effect of secreted frizzledrelated proteins(s FRPs) on CXC chemokine expression in human mesenchymal stem cells(h MSCs).METHODS: CXC chemokines such as CXCL5 and CXCL8 are induced in h MSCs dur...AIM: To investigate the effect of secreted frizzledrelated proteins(s FRPs) on CXC chemokine expression in human mesenchymal stem cells(h MSCs).METHODS: CXC chemokines such as CXCL5 and CXCL8 are induced in h MSCs during differentiation with osteogenic differentiation medium(OGM) and may be involved in angiogenic stimulation during bone repair. h MSCs were treated with conditioned medium(CM) from L-cells expressing non-canonical Wnt5 a protein, or with control CM from wild type L-cells, or directly with s FRPs for up to 10 d in culture. m RNA expression levels of both CXCL5 and CXCL8 were quantitated by real-time reverse transcriptase-polymerase chain reaction and secreted protein levels of these proteins determined by ELISA. Dose-(0-500 ng/m L) and time-response curves were generated for treatment with s FRP1. Signal transduction pathways were explored by western blot analysis with pan- or phosphorylation-specific antibodies, through use of specific pathway inhibitors, and through use of si RNAs targeting specific frizzled receptors(Fzd)-2 and 5 or thereceptor tyrosine kinase-like orphan receptor-2(Ro R2) prior to treatment with s FRPs. RESULTS: CM from L-cells expressing Wnt5 a, a noncanonical Wnt, stimulated an increase in CXCL5 m RNA expression and protein secretion in comparison to control L-cell CM. s FRP1, which should inhibit both canonical and non-canonical Wnt signaling, surprisingly enhanced the expression of CXCL5 at 7 and 10 d. Dickkopf1, an inhibitor of canonical Wnt signaling prevented the s FRPstimulated induction of CXCL5 and actually inhibited basal levels of CXCL5 expression at 7 but not at 10 d post treatment. In addition, all four s FRPs isoforms induced CXCL8 expression in a dose- and time-dependent manner with maximum expression at 7 d with treatment at 150 ng/m L. The largest increases in CXCL5 expression were seen from stimulation with s FRP1 or s FRP2. Analysis of mitogen-activated protein kinase signaling pathways in the presence of OGM showed s FRP1-induced phosphorylation of extracell展开更多
基金the Institute of Health Carlos Ⅲ(ISCⅢ)No.PI16/01800 and PIE16/00011
文摘Colorectal cancer(CRC) is the third most common cancer in men and the second most common cancer in women,worldwide. In the early stages of the disease, biomarkers predicting early relapse would improve survival rates.In metastatic patients, the use of predictive biomarkers could potentially result in more personalized treatments and better outcomes. The CXC family of chemokines(CXCL1 to 17) are small(8 to 10 kDa) secreted proteins that attract neutrophils and lymphocytes. These chemokines signal through chemokine receptors(CXCR) 1 to 8.Several studies have reported that these chemokines and receptors have a role in either the promotion or inhibition of cancer, depending on their capacity to suppress or stimulate the action of the immune system, respectively.In general terms, activation of the CXCR1/CXCR2 pathway or the CXCR4/CXCR7 pathway is associated with tumor aggressiveness and poor prognosis; therefore,the specific inhibition of these receptors is a possible therapeutic strategy. On the other hand, the lesser known CXCR3 and CXCR5 axes are generally considered to be tumor suppressor signaling pathways, and their stimulation has been suggested as a way to fight cancer.These pathways have been studied in tumor tissues(using immunohistochemistry or measuring mRNA levels)or serum [using enzyme-linked immuno sorbent assay(ELISA) or multiplexing techniques], among other sample types. Common variants in genes encoding for the CXC chemokines have also been investigated as possible biomarkers of the disease. This review summarizes themost recent findings on the role of CXC chemokines and their receptors in CRC and discusses their possible value as prognostic or predictive biomarkers as well as the possibility of targeting them as a therapeutic strategy.
基金Supported by Merit Review Award from the United States,Department of Veterans Affairs Biomedical Laboratory Research and Development Service of the VA Office of Research and Development,No.I01BX000170
文摘AIM: To investigate the effect of secreted frizzledrelated proteins(s FRPs) on CXC chemokine expression in human mesenchymal stem cells(h MSCs).METHODS: CXC chemokines such as CXCL5 and CXCL8 are induced in h MSCs during differentiation with osteogenic differentiation medium(OGM) and may be involved in angiogenic stimulation during bone repair. h MSCs were treated with conditioned medium(CM) from L-cells expressing non-canonical Wnt5 a protein, or with control CM from wild type L-cells, or directly with s FRPs for up to 10 d in culture. m RNA expression levels of both CXCL5 and CXCL8 were quantitated by real-time reverse transcriptase-polymerase chain reaction and secreted protein levels of these proteins determined by ELISA. Dose-(0-500 ng/m L) and time-response curves were generated for treatment with s FRP1. Signal transduction pathways were explored by western blot analysis with pan- or phosphorylation-specific antibodies, through use of specific pathway inhibitors, and through use of si RNAs targeting specific frizzled receptors(Fzd)-2 and 5 or thereceptor tyrosine kinase-like orphan receptor-2(Ro R2) prior to treatment with s FRPs. RESULTS: CM from L-cells expressing Wnt5 a, a noncanonical Wnt, stimulated an increase in CXCL5 m RNA expression and protein secretion in comparison to control L-cell CM. s FRP1, which should inhibit both canonical and non-canonical Wnt signaling, surprisingly enhanced the expression of CXCL5 at 7 and 10 d. Dickkopf1, an inhibitor of canonical Wnt signaling prevented the s FRPstimulated induction of CXCL5 and actually inhibited basal levels of CXCL5 expression at 7 but not at 10 d post treatment. In addition, all four s FRPs isoforms induced CXCL8 expression in a dose- and time-dependent manner with maximum expression at 7 d with treatment at 150 ng/m L. The largest increases in CXCL5 expression were seen from stimulation with s FRP1 or s FRP2. Analysis of mitogen-activated protein kinase signaling pathways in the presence of OGM showed s FRP1-induced phosphorylation of extracell
