Sample Banking in Renal Cancer

Transcription

Sample Banking in Renal Cancer
Sample Banking in Renal Cancer
- A Consideration of Some Issues -
Roz Banks
Clinical and Biomedical Proteomics Group
Cancer Research UK Clinical Centre
St James’s University Hospital
Leeds, UK
www.proteomics.leeds.ac.uk
Why Bank Samples?
• Essential if furthering our knowledge of renal cancer and potentially
developing new biomarkers (diagnostic, prognostic, predictive…….) or
therapies for example
• Investment for the future – expedites translation of findings. If high quality
(samples, processing and clinical annotation), can be used in new studies
as new technologies/results emerge
• Need multiple banks for RCC to ensure representative and sufficient numbers
of samples and multi-centre validation of findings
BUT Any Centre Needs:
a defined reason for doing it, realistic plans to use
and/or release them and quality banking procedures
– gift from the patient and non-trivial financial
investment so various obligations
CRUK
LTHT NHS Trust
Oncology
Urology
Pathology
Clinical Chemistry
Leeds University
Patients
Clinical &
Biomedical
Proteomics Group
Research Tissue Bank
Tissue
Blood
Protein and Gene
Studies
e.g.
• CRUK Proteomics
Programme
• EU CAGEKID €10.5M
(RCC whole genome
sequencing etc)
Clinical
data
Urine
New pathways,
biomarkers & drug
targets
Patient Benefit
Individualisation of diagnosis &
treatment
Improved safety & quality of
life
Partner Benefit
More efficient use of £££
Research ability/reputation
IP
A Sample Banking Pathway
Clinical Trial
Biomarker
Study
(internal & external)
• Dedicated team/lab including QA
Manager – GCLP development
ongoing
Ethics
• Collaboration with clinical teams
Research
Nurses &
Clinicians
Patient Recruitment
• Detailed study-specific SOPs
Clinical Data
• Bar-coding and secure databases
Research
Nurses &
Technicians
Sample Collection
(Study-specific timing and type)
QA Manager
Research
Technicians
Sample Processing
(Study-specific SOP)
Sample Bank
Sample Data
Ethics/Regulatory Issues
•
Ensure compliance with relevant regulations/guidance
e.g. Human Tissue Act, Data Protection Act, EU Directives,
GCP and MHRA guidelines etc
•
International studies – be aware of differences in requirements
between different countries
•
Need relevant ethics/IRB approval. Newer technologies
e.g. whole genome sequencing potentially have major
personal implications which need to have been explicitly covered.
•
Obtain broad patient consent to maximise potential future use
of the samples – consider “research tissue bank” status with
defined access policies
Which Patient Groups?
Depends on research questions – consider the bigger picture
e.g. Leeds Proteomics Group – broad biomarker-based discovery/validation etc:
RCC
• Ongoing
• >500 plasma/serum/urine at diagnosis
• >350 matched normal and tumour frozen tissue
• Patients in TKI trials (longitudinal)
Nephrectomy
• Population-based TMA under construction
• Extensive clinical data and follow-up
RCC/matched normal
cortical tissue
Sample Collection
Others
Annotation
• Controls (healthy and benign urological disease)
• Living donors (controls for nephrectomy effects)
Frozen Tissue Bank
• Nephrotoxicity study
• Renal medicine
• Clinical trials
Proteomics
Clinical history,
histopathology,
follow-up
FFPE Tissue bank
FFPE
blocks
Tissue
microarrays
How Should Samples Be Banked?
Sample types - depend on the research needs and the practical issues
Frozen
•
Tissue
Derived primary cell lines
Formalin-fixed paraffin-embedded (FFPE)
•
Fluids
Blood
Plasma
Serum
PBMC/Buffy Coat
Urine
Critical that samples are collected consistently according to Standard
Operating Protocols (SOPs) together with high quality clinical data
Samples should be logged and mirror-banked in secure alarmed
freezers/liquid nitrogen banks
Pre-Analytical Effects
All may influence the outcome of the research studies
•
Biological (in vivo)
Age, gender, diet, time of day, concomitant illness, ethnicity…..
•
Technical (in vitro)
sample collection (op procedure/hypoxic time, venepuncture
method effects)
sample handling (delay, fixative/anticoagulant, pH, temp, time)
storage (length & temp)……….
Nucleic acids, proteins and their post-translational modifications
vary tremendously in terms of stability
Frozen tissue
Key issues: time delays, method and rate of freezing, storage
length and temperature, representative sampling
Limited studies generally and none in RCC - need for more investigation
and also stringent validation
Tissue – time to freezing
Skold et al (2007) – postmortem brains (no renal examples)
Peptides
t=0 mins
t=10 mins
Proteins
53/1500 proteins on
2D-DIGE changed by
>1.5 fold
Phosphorylation
Heterogeneity of Tissue Samples - QC
If extracting, check sections from the actual blocks used in analysis (ICGC)
Uniform –
mainly
tumour cells
Granular
and clear
cells,
PBMCs
Fibrosis –
minimal
tumour cells
Mixed
grade
areas
Formalin-fixed paraffin-embedded (FFPE) tissue
May often be only option
• DNA/RNA analyses
Often used – limited to short amplicons. Can produce fixationinduced artefactual “mutations”
• Protein analyses
Care with IHC and antigen retrieval
Cross-links prevent use of FFPE tissue in proteomic studies???
Be aware of dangers of analysis of phosphorylation status
Many effects from fixative duration, fixative age, size of blocks etc
Fluids
• Type of tube
Manufacturer, gel/no gel, anticoagulant type
• Time
Delay between venepuncture and processing
Length of storage
•
Temperature
Interval and centrifugation – “RT” or 4oC
Storage - -20oC or -80oC
Blood tube type (gel/non-gel) and temperature
Neutrophil elastase complex – a marker of inflammation
(similar results for VEGF measurements)
Elastase complex (pg/ml)
Serum
800
4
4 gel
RT
RT gel
700
600
500
400
300
200
100
0
1
2
3
4
5
6
Donor
Serum also much higher than plasma
Conclusions
•
Need for coordinated sample banking across multiple centres in RCC
to facilitate translational research in RCC
• Samples should be collected so that they are “fit for purpose” with
QC processes and relevant clinical data
• Samples and data should be stored securely
• No single ideal method for sample processing - key is to be consistent
(SOPs) and to record the various variables to avoid bias
• More systematic studies of pre-analytical factors are needed
Clinical Proteomics Group
St James’s University Hospital - Leeds
Pat Harnden – Pathology
Medical Oncology team
Urology team
Renal Medicine team
Peter Selby (co-PI)
(www.proteomics.leeds.ac.uk)
The Patients
Funders
CR-UK, DoH, NIHR, MRC, EU, Kidney Research UK , TSB