Ribosomal Dysfunction Results in an Immunologic Susceptibility to Lung Cancer

1
Ribosomal Dysfunction Results in an Immunologic
Susceptibility to Lung Cancer

• Stephanie Chang MD, Ryuji Higashikubo PhD, Saeed
  Arefanian MD, Andrew Gelman PhD, Daniel Kreisel
  MD, PhD, Alexander Krupnick MD
• April 27th,2015

Department of Surgery Division of Cardiothoracic
Surgery
2
Disclosures

• No financial disclosures

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Susceptibility to Lung Cancer
Lung Cancer Resistant

• Previous work from our lab demonstrates natural
  killer (NK) cells play a role in this process
• Cancer Research 2012

Smoker with Bullous Emphysema
Lung Cancer Susceptible
Non-Smoker with Lung Cancer
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Expression of Sly 1 Correlates with Immunologic
Resistance to Lung Cancer

• X chromosome linked protein with unknown function

Sly1 380 AA 55 kD
Protein protein binding domains
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Objective

• The aim of this study was to determine the role
  of Sly 1 in the susceptibility to lung cancer
  development

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Expression of Sly 1 Correlates with Immunologic
Resistance to Lung Cancer
Humans
TNF a NK Cells
Lung Cancer Resistant
Lung Cancer Susceptible
Sly 1 Level by RT-PCR (normalized to
b-Actin/standardized patient)
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Expression of Sly 1 Correlates with Immunologic
Resistance to Lung Cancer
Human Sly 1 Function
TNF a NK Cells
Lung Cancer Resistant
Lung Cancer Susceptible
Sly 1 Level by RT-PCR (normalized to
b-Actin/standardized patient)
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Sly 1 Contributes to NK Cytotoxicity
Sly1- (knockout of the gene)
Wild-type littermates
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Sly 1 Contributes to NK Cytotoxicity
Sly1- (knockout of the gene)
Wild-type littermates
Activating Receptors Expression
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Sly 1 Expression Influences Lung Cancer Growth
Via NK Cells
Lewis Lung Carcinoma Tumor Growth
Control Group
Tumor Volume (mm3)
Days After Injection
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Sly 1 Contributes to NK Cytotoxicity of Lung
Cancer
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Sly 1 is a Ribosome Associated Protein

• Immunoprecipitation of WT and Sly 1 KO NK cell
  lysates with anti-Sly 1 Ab to evaluate Sly 1
  binding partners
• No detection of signaling proteins from
  activating receptors or cytokine pathways

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Sly 1 Affects mRNA levels
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How Could a Ribosomal Protein Impair Gene
Expression?
ribosome

• mRNA binding
• - No RNA-binding capacity

40s
mRNA
2) Ribosomal instability - Affects the
transcription factor E2F as a protective
mechanism
60s
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How Could a Ribosomal Protein Impair Gene
Expression?
Normal Cell
mRNA
E2F
promoter
ribosome
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How Could a Ribosomal Protein Impair Gene
Expression?
Ribosomal Stress Associated with Malignant
Transformation or Cell Stress
P
P
P
P
P
kinase
X
P
P
p53
P
Stop cellular proliferation and activation
p27
p21
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How Could a Ribosomal Protein Impair Gene
Expression?
Ribosomal Stress Associated with Malignant
Transformation or Cell Stress
P
P
P
P
P
kinase
X
P
P
p53
P
p27
p21
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High-dose IL-2 Can Stabilize the Ribosome
Lewis Lung Carcinoma Lysis in vitro
Activating Receptors Expression
At Rest
IL-2
At Rest
IL-2
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Conclusions

• Sly1 is a ribosomal protein that affects NK
  ribosome stability at rest
• Ribosomal stress is a sign of malignant
  transformation which can destroy the cell or
  decrease its activation/viability
• Prior to our research, most X linked
  ribosomopathies were considered severely
  disabling but we now demonstrate that subtle
  defects can manifest such as NK dysfunction and
  immunologic susceptibility to lung cancer
• IL2 can alleviate ribosomal stress and may be
  useful in lung cancer immunotherapy

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Acknowledgements

• Thoracic Surgery Foundation for Research and
  Education
• NIH Ruth L Kirschstein NRSA
• Thoracic Immunology Lab
• Eberhard-Karls University Tuebingen
• Sandra Beer-Hammer, PhD
• Daniel Schall, PhD

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Questions?