The HOPE fixation technique--a promising alternative to common prostate cancer biobanking approaches.
Author(s): Braun M, Menon R, Nikolov P, Kirsten R, Petersen K, Schilling D, Schott C, Gündisch S, Fend F, Becker KF, Perner S
Publication: BMC Cancer, 2011, Vol. 11, Page 511
PubMed ID: 22151117 PubMed Review Paper? No
Purpose of Paper
Conclusion of Paper
Studies
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Study Purpose
The purpose of this study was to compare morphology and protein yield and integrity of ten case-matched surgically-resected prostate specimens preserved by snap-freezing in liquid nitrogen, FFPE, or HOPE fixation followed by paraffin embedding.
Summary of Findings:
Case-matched FFPE and HOPE-fixed prostate specimens displayed comparable morphology, while freeze-induced artifacts and distorted morphology were reported for specimens that were snap frozen in liquid nitrogen. IHC staining for prostate-specific antigen (PSA), Golgi phosphoprotein 2 (GOLPH2), and p63 was comparable between FFPE and HOPE-preserved specimens, although an antigen retrieval step was required for specimens preserved by FFPE but not HOPE. Snap-frozen specimens displayed more prominent background staining than FFPE or HOPE-fixed specimens. Total protein yields and Western blot analyses were comparable across differentially fixed specimens.
Biospecimens
Preservative Types
- Frozen
- Other Preservative
- Formalin
Diagnoses:
- Neoplastic - Carcinoma
- Neoplastic - Benign
Platform:
Analyte Technology Platform Morphology H-and-E microscopy Protein Immunohistochemistry Protein Western blot Protein Spectrophotometry Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Biospecimen Preservation Type of fixation/preservation Formalin (buffered)
Snap frozen
HOPE
Immunohistochemistry Specific Targeted peptide/protein PSA
GOLPH2
p63
Western blot Specific Targeted peptide/protein GOLPH2
PSA
Beta-actin
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Study Purpose
The purpose of this study was to compare DNA and RNA integrity and suitability for molecular analysis of ten case-matched surgically-resected prostate specimens preserved by snap freezing in liquid nitrogen, FFPE, or HOPE fixation followed by paraffin embedding.
Summary of Findings:
PCR amplification success rates were influenced by preservation method and amplicon length. PCR analysis of 100-600 bp amplicons was successful for snap-frozen and HOPE-fixed, paraffin-embedded specimens, while PCR success was limited to 100-400 bp amplicons for FFPE specimens. qRT-PCR analysis of a six patient subset revealed that differences in Ct values for three reference genes (TBP, GAPDH, beta-actin) were significant among differentially preserved specimens (p<0.05). The magnitude of Ct differences was greatest between snap-frozen and FFPE specimens which had the lowest and highest mean values, respectively, and differed by 6, 8, and 10 cycles for TBP, GAPDH, and beta-actin, respectively. The magnitude of Ct differences was notably smaller between snap-frozen and HOPE-fixed specimens which differed by 1-2 cycles for each reference gene. FISH analysis of Ets related gene (ERG) was successful for all specimens, although proteinase pretreatment was required for HOPE-fixed specimens to enhance signal, and freeze-induced artifacts were observed among snap-frozen specimens.
Biospecimens
Preservative Types
- Frozen
- Other Preservative
- Formalin
Diagnoses:
- Neoplastic - Carcinoma
- Neoplastic - Benign
Platform:
Analyte Technology Platform DNA FISH DNA PCR RNA Spectrophotometry RNA Real-time qRT-PCR Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Biospecimen Preservation Type of fixation/preservation Snap frozen
Formalin (buffered)
HOPE
Real-time qRT-PCR Specific Targeted nucleic acid TBP
GAPDH
Beta-actin
FISH Specific Targeted nucleic acid ERG
PCR Specific Targeted nucleic acid TBXAS1
RAG1
PLZF
AF4
PCR Specific Length of gene fragment 100 bp
200 bp
300 bp
400 bp
600 bp