IMIQUIMOD, AN IMMUNE-RESPONSE IMIQUIMOD, AN IMMUNE-RESPONSE MODIFIER, IN THE TREATMENT OF MODIFIER, IN THE TREATMENT OF

TRANSITIONAL CELL CARCINOMA OF TRANSITIONAL CELL CARCINOMA OF THE BLADDERTHE BLADDER

Douglas Scherr, M.D.Douglas Scherr, M.D.

Department of UrologyDepartment of Urology

New York Presbyterian Hospital-Weill Cornell New York Presbyterian Hospital-Weill Cornell Medical CenterMedical Center

IntroductionIntroduction

• Imiquimod is a potent synthetic Imiquimod is a potent synthetic immunomodulatorimmunomodulator

• Currently used as a first-line Currently used as a first-line treatment for genital condyloma (Aldara, 3M)treatment for genital condyloma (Aldara, 3M)

• Effective against several skin cancers Effective against several skin cancers including melanoma and basal cell including melanoma and basal cell carcinomacarcinoma

IntroductionIntroduction

• Induces both innate and acquired immune Induces both innate and acquired immune responsesresponses

• Toll-like receptor 7 (TLR-7) agonistToll-like receptor 7 (TLR-7) agonist

• Stimulates dendritic cells to mature and Stimulates dendritic cells to mature and secrete pro-inflammatory cytokinessecrete pro-inflammatory cytokines

• Mechanism strikingly similar to bacillus Mechanism strikingly similar to bacillus Calmette-Guerin (BCG)Calmette-Guerin (BCG)

IntroductionIntroduction

• Hypothesis: Hypothesis: – Imiquimod may have therapeutic potential Imiquimod may have therapeutic potential

against transitional cell carcinoma of the bladderagainst transitional cell carcinoma of the bladder

• Objectives:Objectives:– To determine if Imiquimod has direct effects on To determine if Imiquimod has direct effects on

bladder cancer cells bladder cancer cells in vitroin vitro– To determine if Imiquimod has anti-tumor effects To determine if Imiquimod has anti-tumor effects

in vivoin vivo in an intact immune system in an intact immune system

Cell ViabilityCell Viability(MTT Assay)(MTT Assay)

Cytokine ProductionCytokine Production (ELISA)(ELISA)

ApoptosisApoptosis(TUNEL Assay)(TUNEL Assay)

ImiquimodImiquimod

Bladder CancerBladder CancerCell LinesCell Lines

(J82, T24, TCC-SUP)(J82, T24, TCC-SUP)

24 hrs24 hrs

In vitroIn vitro Methods Methods

Figure 1. Cell Proliferation Assays

MTT Proliferation Assay after 24hrs

0

20

40

60

80

100

120

0 50 100 150 200 250

Imiquimod Concentration (mcg/ml)

Frac

tiona

l %

J82

T24

TCCSUP

Cell ViabilityCell Viability

ApoptosisApoptosis

Control (PBS) GroupControl (PBS) Group Imiquimod GroupImiquimod Group

ApoptosisApoptosis

Imiquimod GroupImiquimod GroupControl (PBS) GroupControl (PBS) Group

Apoptosis in vitro

0

4

8

12

16

20

24

% a

popt

otic

cel

ls PBS treated

Imiquimod treated

0.8%

17.1%

ApoptosisApoptosis

IL-6 Secretion

0

200

400

600

800

1000

1200

1400

1600

1800

2000

pg/m

l PBS treated

Imiquimod treated

TNF-alpha Secretion

0

200

400

600

800

1000

1200

1400

pg/m

l PBS treated

Imiquimod treated

930

425

1340

480

Cytokine ProductionCytokine Production

In vivoIn vivo Methods Methods

• Orthotopic, syngeneic, immune competent Orthotopic, syngeneic, immune competent mouse model mouse model (Bochner et al J. Urology, 2003)(Bochner et al J. Urology, 2003)

• Murine bladder tumor (MBT-2) cells instilled Murine bladder tumor (MBT-2) cells instilled intravesically into C3H miceintravesically into C3H mice

• Treatment regimen:Treatment regimen:– Day 0: Tumor cells instilledDay 0: Tumor cells instilled– Day 1:Day 1: Treatment with Imiquimod or PBS Treatment with Imiquimod or PBS– Day 8: Retreated Day 8: Retreated – Day 15: Mice sacrificed Day 15: Mice sacrificed

ImiquimodImiquimodControl (PBS)Control (PBS)

ConclusionsConclusions

• Imiquimod is a potent immune-response Imiquimod is a potent immune-response modifiermodifier

• Has direct biological effects on bladder Has direct biological effects on bladder cancer cell linescancer cell lines

• Preliminary data suggests anti-tumor Preliminary data suggests anti-tumor effects effects in vivoin vivo

• Imiquimod may be a potential Imiquimod may be a potential immunotherapy for bladder cancerimmunotherapy for bladder cancer

AcknowledgementsAcknowledgements

PI: PI: Douglas Scherr, MDDouglas Scherr, MD

Contributors:Contributors:

Hideki Kawamoto, MDHideki Kawamoto, MD

Xuecke You, MDXuecke You, MD

Mathew Albert, PhDMathew Albert, PhD