Whole Transcriptome Profiling of Adrenocortical Tumors Using Formalin-Fixed Paraffin-Embedded Samples

Area of Science:

• Endocrinology
• Genomics
• Oncology

Background:

• Whole transcriptome profiling is valuable for adrenal studies.
• Its utility with formalin-fixed paraffin-embedded (FFPE) samples requires further investigation.
• FFPE samples are more accessible for retrospective studies.

Purpose of the Study:

• To evaluate the use of transcriptome data from FFPE samples of adrenocortical tumors.
• To compare FFPE and fresh frozen samples for transcriptome profiling.
• To assess FFPE sample utility in distinguishing tumor types and identifying marker genes.

Main Methods:

• Whole transcriptome profiling was performed on FFPE and fresh frozen samples from adrenocortical carcinoma (ACC), aldosterone-producing adenoma (APA), and cortisol-producing adenoma (CPA).
• Similarity and correlation between transcriptome data from FFPE and fresh frozen samples were examined.
• Consensus clustering and principal component analysis were used to distinguish tumor types.
• Differential gene expression analysis was conducted to detect marker genes.

Main Results:

• Transcriptome data from FFPE and fresh frozen samples showed high correlation (r = 0.93).
• FFPE samples allowed for successful distinction between adrenocortical tumor types.
• Known marker genes for ACC (e.g., CCNB2, TOP2A) and APA (e.g., CYP11B2, KCNJ5) were identified in FFPE samples.

Conclusions:

• FFPE samples are a reliable alternative to fresh frozen samples for whole transcriptome profiling of adrenocortical tumors.
• Transcriptome data from FFPE samples can be effectively used for tumor classification and biomarker discovery.
• This finding expands the potential for utilizing archived FFPE tissues in adrenal tumor research.