3 replies to this topic

[cardosopedro]

Hi.

I was wondering if there is, here in the forum, some expert in the PI3K/Akt pathway... I'm treating cells with a drug that is interfering with this pathway... But some results are hard to explain.

1) I have a reduction in the expression of PI3K, meaning (in principle) that the effect is very upstream in the pathway, right? Any idea about what it can be targeting?

2) Although I observe a decrease in PI3K and phospho-Akt, I also observe an increase in the expression of mTOR... (and decrease in 4E-BP1). Does someone know anything that can explain this mTOR accumulation?


Thanks in advance for any possible idea!

[Inmost sun]

cardosopedro, on May 24 2010, 01:44 PM, said:

Hi.

I was wondering if there is, here in the forum, some expert in the PI3K/Akt pathway... I'm treating cells with a drug that is interfering with this pathway... But some results are hard to explain.

1) I have a reduction in the expression of PI3K, meaning (in principle) that the effect is very upstream in the pathway, right? Any idea about what it can be targeting?

2) Although I observe a decrease in PI3K and phospho-Akt, I also observe an increase in the expression of mTOR... (and decrease in 4E-BP1). Does someone know anything that can explain this mTOR accumulation?


Thanks in advance for any possible idea!

there seem to be nice results; you may work out the kinetics of expression; a short-time exposure of your drug, however, should only have a minor effect on gene expression; do you know the target of your drug, or do you have to find it?

[cardosopedro]

Inmost sun, on May 25 2010, 10:50 PM, said:

cardosopedro, on May 24 2010, 01:44 PM, said:

Hi.

I was wondering if there is, here in the forum, some expert in the PI3K/Akt pathway... I'm treating cells with a drug that is interfering with this pathway... But some results are hard to explain.

1) I have a reduction in the expression of PI3K, meaning (in principle) that the effect is very upstream in the pathway, right? Any idea about what it can be targeting?

2) Although I observe a decrease in PI3K and phospho-Akt, I also observe an increase in the expression of mTOR... (and decrease in 4E-BP1). Does someone know anything that can explain this mTOR accumulation?


Thanks in advance for any possible idea!

there seem to be nice results; you may work out the kinetics of expression; a short-time exposure of your drug, however, should only have a minor effect on gene expression; do you know the target of your drug, or do you have to find it?

my drug is a phosphatase inhibitor... so PTEN is a target. Awkwardly, by inhibiting PTEN (and I observe a decrease in PTEN levels) I would expect an upregulation of the pathway but instead it seems like the pathway is downregulated. I attribute this to something that is happening upstream of PI3K...

[Inmost sun]

the major phosphoprotein phosphatases have multiple function; so, if you do not inhibit a dedicated phosphatase specifically, it will be difficult to decide if only PTEN was targeted; a phosphoproteom analysis may help