From this, we defined an selleck bio ER phosphorylation score, taking into account the phosphorylation status of ER at each of the seven sites interrogated. This so called P7 score was significantly associated with OS from Inhibitors,Modulators,Libraries breast cancer death and relapse free survival in multivariate analysis. Due to the relationship of p S2448 mTOR with clinical outcome in this cohort, we investigated the relationship of p S2448 mTOR to different phosphorylated forms of ER in these samples. p S2448 mTOR was positively correlated with p S118 ER, p S167 ER, p S282 ER, but negatively correlated with p T311 ER. Previously we had shown that detection of several phosphorylation sites on ER, p S104 106 ER, p S118 ER, p S167 ER, p S282 ER and p S294 ER, were associated with a good clinical outcome while p T311 ER and p S559 ER were associated with poor clinical outcome.

In the current study we found that p mTOR was positively associated with p S118 ER, p S167 ER, p S282 ER but negatively Inhibitors,Modulators,Libraries associated with p T311 ER, which suggested an inverse relationship with the P7 ER score and indeed p S2448 mTOR expression was found negatively correlated with P7 ER score. When tumors were dichotomized into high P7 ER score versus low P7 ER score the IHC scores for p S2448 mTOR were significantly higher Inhibitors,Modulators,Libraries in low versus high P7 ER score tumors. These data further support an association of high p S2448 mTOR with good prognosis. Since P7 score remained significant Inhibitors,Modulators,Libraries on multivariate analysis as previously described but p S2448 mTOR did not, the relationship of p S2448 mTOR to P7 score is likely driving its association with clinical outcome.

Nuclear staining for p S2448 mTOR has been previously reported and in the current cohort was detected in approximately 10% of assessable cases. Nuclear p S2448 mTOR was correlated with cytoplasmic p mTOR and while nuclear p S2448 mTOR showed similar trends in terms of relationships to phosphorylated P7 ER score, it was not analyzed Inhibitors,Modulators,Libraries further due to the small numbers of positive cases. Relationship of p70S6K to activated mTOR and phosphorylated ER To explore further the relationship of phosphorylated ER to the activated mTOR pathway, specifically the mTOR complex 1, TMA sections from the above breast cancer cohort were examined for the expression of p70S6K, a downstream target of p S2448 mTOR within the mTORC1.

Both nuclear and cytoplasmic staining for p T389 p70S6K and total p70S6K have been reported and both were scored separately in the above cohort. The majority of cases were positive for both cytoplasmic and nuclear p T389 p70S6K as well as total p70S6K. As expected both cytoplasmic and nuclear p T389 p70S6K and total p70S6K were positively correlated glucose metabolism with both total and p S2448 mTOR. Neither cytoplasmic nor nuclear p T389 p70S6K was associated with the P7 ER score.