TITLE:
Trefoil Factor 3 (TFF3) mRNA Expression Level in Follicular Thyroid Tumors Using Formalin-Fixed, Paraffin-Embedded (FFPE) Blocks
AUTHORS:
Saydiganikhodja Ismailov, Murodjon Rashitov, Makio Kobayashi, Noriyuki Shibata, Yoichiro Kato, Yoko Omi, Masatoshi Iihara, Takahiro Okamoto
KEYWORDS:
Follicular Thyroid Tumors; TFF3; RT-qPCR; Formalin-Fixed Paraffin-Embedded Tissue
JOURNAL NAME:
Open Journal of Pathology,
Vol.3 No.2,
April
25,
2013
ABSTRACT:
Background: Differential diagnosis of follicular thyroid carcinoma (FTC) from follicular
thyroid adenoma (FTA) is often difficult since presence or absence of capsular/vascular
invasion can not be determined by preoperative fine needle aspiration cytology,
and may not be judged unanimously on permanent sections even among experienced pathologists.
Determination of molecular-genetic factors such as trefoil factor 3 (TFF3) mRNA in the follicular thyroid tumors may be useful aid to improve the
accuracy of diagnosis, though it is considered to be unstable and relatively low
concentrated genetic substance. Purpose of our study is to investigate expression
level of TFF3 mRNA
of thyroid follicular tumors using formalin-fixed, paraffin-embedded (FFPE) tissue. Methods: Study population included FFPE sections from 19 FTC cases, 20 FTA cases, 11
adenomatous goiter (G) cases and 12 samples of normal thyroid tissue (N) adjacent
to thyroid tumors. RNeasy FFPE kit was used for extraction of total RNA. Purification
and concentration values were determined by spectrophotometer. Extracted RNA was
used for cDNA synthesis in reverse transcription. Synthesized cDNA subsequently
proceeded for relative quantification of TFF3 mRNA by RT-qPCR using TFF3 primers. Glyceroldehyde-3-phosphate
dehydrogenase (GAPDH) and hypoxanthin phosphorobosyltransferase1 (HPRT1) were used
as control genes. The mean and standard deviation of TFF3 mRNA expression level were analyzed by
software Multiplate RQ. Results: Extraction by the FFPE kit yielded high concentration of RNA in all cases.
Purification values were 1.8 in
average. Concentration values were significantly higher in FTC and FTA relative
to G and N tissues, possibly due to high density of thyrocytes in the samples. Relative
quantification of TFF3 mRNA
expression level showed broad ranges both in FTC and FTA, while the analyses in
G and N tissues indicated narrow ranges. Conclusion: FFPE tissues from thyroid follicular tumors
can be used for measurement of unstable and low concentrated genetic substances
such as TFF3 mRNA. Its diagnostic value yet remains to be determined.