Cancer cell

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Cancer cellselective in vivo
near infrared photoimmunotherapy targeting
specific membrane molecules
 Makoto Mitsunaga, Mikako Ogawa, Nobuyuki Kosaka,
Lauren Rosenblum, Peter L Choyke Hisataka
Kobayashi
        Treating cancer with light activated,
antibody-dye conjugates              
by Amol Kapoor and Teddy Leithead
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Overview

• Cancer treatments focus on minimal side effects
  with maximal cancer cell death
• Photoimmunotherapy (PIT) 
• IR700 Trastuzumab and Panitumumab. 
• IR700 toxic only when bound
• Specific antibodies could allow for the 
•       treatment of many cancers

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   Background

• Photo Dynamic Therapy (PDT)
• Excited photosensitizers -gt Singlet oxygen
• Singlet oxygen -gt cell death
•                                                 
•                                         

•     Immunotherapy
• Uses the body's defense mechanism
• Antibodies

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Introduction

• PIT PDT Immunotherapy
• PDT -gt Toxicity 
• Immunotherapy -gt Specificity 
• PIT makes a strong therapy because of low healthy
  cell death

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Review

• PDT                                        
                               PIT
•                 
•                             Immunotherapy
•                                      
•                     
•   
•                                             

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Results-In Vitro

• 3T3-HER2 cells and A431 HER1 cells
• Significant cell death from both conjugates
• Irradiation -gt Cell death

73
78
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Results-In Vitro (Cont.)

• Tra-IR toxic only when bound
• Cellular uptake is unnecessary

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Results-In Vivo

•  

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Results-In Vivo (Cont.)

• Tumor size
• Life span

• Repeated treatment of drug led to tumor free
  survival at over four months

Rats w/ treatment
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Discussion

• IR700 is hydrophilic and has high extinction
  coefficient
• More effective than other photosensitizers.
• mAb-1700 is highly selective
• Conjugate is non-toxic when unbound
• Email from Kobayashi Mechanism of action and FDA
  trials

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Conclusion/Summary

• A target specific PIT was developed
• NIR light irradiation the conjugate leads to
  large cancer cell death
• Highly effective in vitro and in vivo

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Future Research 

• For clinical trials, mAb-IR700s toxicity
  mechanism must be understood
• Researchers must confirm a minimal threat to
  non-cancerous cells
• Unique mAbs -gt PIT applied to multiple cancers
  for diagnosis and treatment

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Why It Matters

• Completely Revolutionizes Field
• Potentially makes other drugs obsolete
• The likelihood of one of us getting cancer is
  high. Perfected, this offers a way to stop all
  cancers.