Modulation of T cell response by targeting the PI3K‐Akt pathway 

John Janik, M.D.Samir Khleif LaboratoryAugusta University

PI3KδPI3Kδ PI3KβPI3KβPI3KαPI3Kα PI3K

PI3K-Akt Signaling Pathway in T cells

Conventional T cells

Regulatory T cells

?

Normal Cell

T‐Cell

Tregs

T‐Cell

Tregs

CD4+Foxp3‐

CD4+Foxp3+

PI3K

PIP2 PIP3

PTEN, SHIP‐1 and ‐2

Akt

PIP3

PDK‐1PP

T308S473

mTOR

S6K1/2

P

S6

Proliferation

TCR

Stimulation

Effects of PI3K‐Akt pathway inhibition in Tregs vs. Tconv cells

PI3K

PIP2 PIP3

PTEN, SHIP‐1 and ‐2

WM

Akt

PIP3

PDK‐1PP

T308S473

mTOR

S6K1/2

P

S6

TCN

Proliferation

TCR

Stimulation

Effects of PI3K‐Akt pathway inhibition in Tregs vs. Tconv cells

PI3K

PIP2 PIP3

PTEN, SHIP‐1 and ‐2

WM

AktPIP3

PDK‐1PP

T308S473

mTOR

Effects of PI3K‐Akt pathway inhibition in Tregs vs. Tconv cells

TCR Stimulation ‐ +                 +                 +Treatment              None          None         DMSO          WM

Tconv

Treg

TCR

StimulationpAkt 473

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

US NT DMSO WM

pAkt 473/A

ktCD25‐ (Tconv)CD25+ (Treg)

S6K1/2P

S6

S6 phosphorylation is diminished in mouse Treg in presence PI3K/AKT inhibitors 

Abu Eid R.et al, CIR, 2014 

Effects of PI3K‐Akt pathway inhibition on the TCR/IL2 Induced proliferation  of Tregs vs. Tconv cells

PI3K

PIP2 PIP3

PTEN, SHIP‐1 and ‐2

WM

AktPIP3

PDK‐1PP

T308S473

mTOR

S6K1/2P

S6

TCN

Proliferation

TCR

Stimulation

Effects of PI3K‐Akt pathway inhibition on the TCR/IL2 Induced proliferation  of Tregs vs. Tconv cells

PI3K

PIP2 PIP3

PTEN, SHIP‐1 and ‐2

WM

AktPIP3

PDK‐1PP

T308S473

mTOR

S6K1/2P

S6

TCN

Proliferation

TCR

Stimulation

Abu Eid R.et al, CIR, 2014 

Inhibition of PI3K‐Akt pathway in vivo

PI3K/ Akt pathway is essential for the in vivo maintenance of Treg in naïve tumor free mice

Abu Eid R.et al, CIR, 2014 ‐7  ‐5  ‐3   0

WM/TCN/MK2206 Collect splenocytes

PI3K/ Akt pathway is essential for the in vivo maintenance of Treg in naïve tumor free mice

Abu Eid R.et al, CIR, 2014 ‐7  ‐5  ‐3   0

WM/TCN/MK2206 Collect splenocytes

PI3K/ Akt pathway is essential for the in vivo maintenance of Treg in naïve tumor free mice

Abu Eid R.et al, CIR, 2014 ‐7  ‐5  ‐3   0

WM/TCN/MK2206 Collect splenocytes

PI3K‐Akt pathway inhibition indirectly decrease tumor growth

CT26 tumor growth

0

100

200

300

400

500

600

700

3 7 10 13 17 20 24

Days post tumor inoculation

Tumor size (m

m2)

PBS

0

Tumor implantation

Abu Eid R.et al, CIR, 2014 

CT26 tumor growth

0

100

200

300

400

500

600

700

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 )

PBSPC61

‐4        0

Tumor implantationPC61

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition indirectly decrease tumor growth

CT26 tumor growth

0

100

200

300

400

500

600

700

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 ) PBSPC61DMSO

‐4        0

Tumor implantationPC61

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition indirectly decrease tumor growth

CT26 tumor growth

0

100

200

300

400

500

600

700

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 )PBSPC61DMSOWM

‐7  ‐5  ‐3   0

Tumor implantationWM

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition indirectly decrease tumor growth

CT26 tumor growth

0

100

200

300

400

500

600

700

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 )PBSPC61DMSOWMTCN

‐7  ‐5  ‐3   0

Tumor implantationTCN

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition indirectly decrease tumor growth

0 Tumor size

EL4

0

100

200

300

400

500

600

700

800

900

3 7 10 13 17 20 24Days post tumor implantation

Tum

or S

ize

(mm

2)NT-PBS

NT‐PBS

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition of tumor growth is Treg‐dependent

‐7  ‐5 ‐3 0 Tumor size

EL4

WM

0

100

200

300

400

500

600

700

800

900

3 7 10 13 17 20 24Days post tumor implantation

Tum

or S

ize

(mm

2)NT-PBSWM-PBS

* p<0.01

NT‐PBS

WM‐PBS

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition of tumor growth is Treg‐dependent

‐4           0 Tumor size

PC61 EL4

0

100

200

300

400

500

600

700

800

900

3 7 10 13 17 20 24Days post tumor implantation

Tum

or S

ize

(mm

2)NT-PBSPC61-PBSWM-PBS

* p<0.01

NT‐PBSPC61‐PBSWM‐PBS

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition of tumor growth is Treg‐dependent

‐4           0              4 Tumor size

PC61 EL4 Treg

0

100

200

300

400

500

600

700

800

900

3 7 10 13 17 20 24Days post tumor implantation

Tum

or S

ize

(mm

2)NT-PBSPC61-PBSWM-PBSPC61-Treg

* p<0.01

NT‐PBSPC61‐PBSWM‐PBSPC61‐Treg

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition of tumor growth is Treg‐dependent

‐7  ‐5 ‐3 0              4 Tumor size

EL4 Treg

WM

0

100

200

300

400

500

600

700

800

900

3 7 10 13 17 20 24Days post tumor implantation

Tum

or S

ize

(mm

2)

NT-PBSPC61-PBSWM-PBSPC61-TregWM-Treg

* p<0.01

NT‐PBSPC61‐PBSWM‐PBSPC61‐TregWM‐Treg

Any effects on vaccine efficacy in vivo?

PI3K‐Akt pathway inhibition of tumor growth is Treg‐dependent

Abu Eid R.et al, CIR, 2014 

PI3K‐Akt pathway inhibition of tumor growth is Treg‐dependent

0

50

100

150

200

250

300

350

UT DMSO WM TCN

Spots p

er m

illion

E7 re‐stimDMSO re‐stim

‐7  ‐5  ‐3   0                   14

E7 Vx Collect splenocytes

No Vx E7 Vx

* *** P<0.05; ** P<0.01

WM/TCN

PI3K‐Akt inhibition enhances vaccine efficacy

Abu Eid R.et al, CIR, 2014 

TC1 tumor growth

0

100

200

300

400500

600

700

800

900

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 )

DMSO-DMSO

Inhibition of PI3K‐Akt synergistically enhances anti‐tumor immune responses

Abu Eid R.et al, CIR, 2014 

TC1 tumor growth

0

100

200

300

400500

600

700

800

900

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 )DMSO-E7DMSO-DMSO

Inhibition of PI3K‐Akt synergistically enhances anti‐tumor immune responses

Abu Eid R.et al, CIR, 2014 

TC1 tumor growth

0

100

200

300

400500

600

700

800

900

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 ) WM-DMSODMSO-E7DMSO-DMSO

Inhibition of PI3K‐Akt synergistically enhances anti‐tumor immune responses

Abu Eid R.et al, CIR, 2014 

TC1 tumor growth

0

100

200

300

400500

600

700

800

900

3 7 10 13 17 20 24

Days post tumor inoculation

Tum

or s

ize

(mm

2 )WM-E7WM-DMSODMSO-E7DMSO-DMSO

Inhibition of PI3K‐Akt synergistically enhances anti‐tumor immune responses

Abu Eid R.et al, CIR, 2014 

Akt inhibition by MK‐2206 enhances the anti‐tumor therapeutic effect of tumor‐specific vaccine..

Abu Eid R.et al, CIR, 2014 

Akt inhibition by MK‐2206 enhances the anti‐tumor immune response of tumor‐specific vaccine

Abu Eid R.et al, CIR, 2014 

WM differentially affects proliferation of human Tregs and Tconv cells

Abu Eid R.et al, CIR, 2014 

A phase Ib /II trial of pembrolizumab and idelalisibin patients with non‐small cell lung cancer (NSCLC) 

Metastatic NSCLC • Progressed on platinum doublets• OR, Not able to tolerate chemo or unwilling to undergo chemotherapy

• OR EGFR, ALK, ROS1 mutations with disease progression on small molecule inhibitors

• may have also failed prior PD‐1/PD‐L1 blockade

Keytruda 200 mg Q3WZydelig 150 mg BID PO

Keytruda 200 mg Q3WZydelig 150 mg BID PO

Phase II(A) 50 PD1N patients (B) 20 PD1P patients

=2/6 DLTone dose lower

For Phase II

lower level if>2/6 DLT

<=1/6 DLT

Phase Ib

A phase Ib /II trial of pembrolizumab and idelalisibin patients with non‐small cell lung cancer (NSCLC) 

Clinical Trials• Vaccine in combination with AKT inhibitors• AKT inhibitor in combination with anti‐PD1

•Samir Khleif•Shamim Ahmad•Pandelakis Koni•Mikayel Mkrtichyan•Rajeev Shrimali•Rasha Abu-Eid•Abdeljabar El Andaloussi•Atbin Doroodchi•Zuzana Berong•Mason Webb•Abdulmoneim Algady

•Tanusree Sen•Stephanie Zdaniv•Michiko Shimoda•Raed Samara•Osama Rahma

• Collaborators:– Theresa Whiteside, U Pitt– Jay Berzofsky, NCI– Nadia Tarasova, NCI– Jeff Schlom, NCI– Micheal Schickler, CureTech– Ramy Ibrahim, AZ– Ross Stewart, AZ– Linda Liu, Medimmune– Sol Langerman Medimmune

Acknowledgments