Other stu dies have also reported increased HIF one translation me diated by means of PI3K Akt. So as to investigate the involvement of a equivalent signalling pathway, we exa mined activation of EGFR, ERK and p38 MAPK and Akt. Our study on Caco 2 cells illustrated selective activation of MAPK ERK1 2 signalling, in contrast to PI3K Akt and P38 MAPK which remained constitutively active irrespec tive of exogenous EGFR stimulation. Due to the fact EGFR activation led to HIF upregulation in Caco 2 cells, a response analogous to that observed with hypoxia or DMOG, we predicted that EGFR induced angiogenic gene profile would parallel that induced by hypoxia or DMOG. Such findings would lend additional impetus in the direction of building novel anti EGFR agents such because the monoclonal antibodies cetuximab and pani tumumab.

The subsequent part of our review consequently aimed to decipher the global involvement of identified an giogenic genes in modulating the tumour microenviron ment. Unexpectedly, our information showed that none of your 84 angiogenic genes top article were affected by EGFR activation, in spite of induction of downstream ERK MAPK signal ling and stabilisation of HIF. The absence of result of EGF alone was also validated by Q PCR for ANGPTL4, EFNA3, TGFB1 and VEGF, genes which demonstrated significant upregulation inside a HIF one dependent manner following exposure of Caco two to DMOG or hypoxia. How ever, each EGFR above activation and hypoxia commonly co exist in the tumour microenvironment and the two could influence upon the differential modulation of angio genic responses induced by either stimulus.

We consequently examined the effect of simultaneous stimulation of Caco two CRC cells working with EGF plus the article source HIF activator DMOG. Our information demonstrated that the previously established hypoxia regulated angiogenic genes were not additional impacted by addition of EGF. Im portantly, we’ve got as an alternative recognized an extra sub set of genes which had been only expressed following mixed EGF and DMOG, and not with either EGF alone or DMOG hypoxia alone. The exceptional profile of eleven extra angiogenic genes which have been only expressed with com bined EGF and DMOG consists of chemokines CCL11 and IL8, EDG1, DNA binding protein inhibitor ID3, Jagged 1, VEGF receptor KDR, NOTCH4, SPHK1 and TGF. Additionally, expression of COL4A3 was also elevated in Caco two exposed for the mixture of EGF plus DMOG, as were ranges of integrin B3 chain, which collectively with V integrin binds tumstatin through an RGD independent mechanism.