Increased yield of total RNA from fine-needle aspirates for use in expression microarray analysis

Area of Science:

• Molecular biology
• Oncology
• Biochemistry

Background:

• Fine-needle aspirate (FNA) samples offer pure tumor cells for molecular analysis.
• High-quality genetic material is essential for gene expression microarrays.
• Optimizing RNA extraction from limited FNA samples is critical.

Purpose of the Study:

• To enhance the efficiency of high-quality total RNA extraction from ex vivo FNA samples.
• To evaluate the utility of RNA from supernatant and cell pellet fractions.
• To improve RNA yield for microarray analysis in breast cancer research.

Main Methods:

• Collected 11 ex vivo breast cancer FNA samples.
• Stored samples immediately in RNAlater RNA Stabilization Reagent.
• Isolated total RNA from both supernatant and cell pellet fractions.
• Analyzed RNA quality and gene expression profiles.

Main Results:

• Approximately 50% of total RNA was recovered from the supernatant.
• RNA from the supernatant exhibited comparable quality to RNA from the cell pellet.
• Gene expression profiles were similar between supernatant and pellet RNA.
• RNAlater facilitated RNA recovery from both fractions.

Conclusions:

• The supernatant fraction of FNA samples stored in RNAlater contains significant, high-quality RNA.
• Discarding the supernatant can lead to a substantial loss of valuable genetic material.
• RNA extraction protocols for FNA samples should include processing the supernatant for comprehensive analysis.