| Autor: |
Corrado A; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy., Aceto R; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy.; Humanitas Clinical and Research Centre-IRCCS, Milan, Italy., Silvestri R; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy., Dell'Anno I; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy., Ricci B; Fondazione I.R.C.C.S., Istituto Neurologico Carlo Besta, Milan, Italy., Miglietta S; San Raffaele Telethon Institute for Gene Therapy (SR-Tiget), IRCCS San Raffaele Scientific Institute, Milan, Italy., Romei C; Endocrine Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy., Giovannoni R; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy., Poliseno L; Institute of Clinical Physiology (IFC), CNR, Pisa, Italy., Evangelista M; Institute of Clinical Physiology (IFC), CNR, Pisa, Italy., Vitiello M; Institute of Clinical Physiology (IFC), CNR, Pisa, Italy., Cipollini M; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy., Garritano S; Centre for Integrative Biology, University of Trento, Trento, Italy., Giusti L; School of Pharmacy, University of Camerino, Camerino, Italy., Zallocco L; Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Siena, Italy.; Department of Pharmacy, University of Pisa, Pisa, Italy., Elisei R; Endocrine Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy., Landi S; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy., Gemignani F; Genetic Unit, Department of Biology, University of Pisa, Pisa, Italy. |
| Abstrakt: |
Background: Galectin-3 ( LGALS3 ) is an important glycoprotein involved in the malignant transformation of thyrocytes acting in the extracellular matrix, cytoplasm, and nucleus where it regulates TTF-1 and TCF4 transcription factors. Within LGALS3 gene, a common single-nucleotide polymorphism (SNP) (c.191C>A, p.Pro64His; rs4644) encoding for the variant Proline to Histidine at codon 64 has been extensively studied. However, data on rs4644 in the context of thyroid cancer are lacking. Thus, the aim of the present work was to evaluate the role of the rs4644 SNP as risk factor for differentiated thyroid cancer (DTC) and to determine the effect on the transcriptome in thyrocytes. Methods: A case/control association study in 1223 controls and 1142 unrelated consecutive DTC patients was carried out to evaluate the association between rs4644-P64H and the risk of DTC. We used the nonmalignant cell line Nthy-Ori (rs4644-C/A) and the CRISPR/Cas9 technique to generate isogenic cells carrying either the rs4644-A/A or rs4644-C/C homozygosis. Then, the transcriptome of the derivative and unmodified parental cells was analyzed by RNA-seq. Genes differentially expressed were validated by quantitative reverse transcription PCR and further tested in the parental Nthy-Ori cells after LGALS3 gene silencing, to investigate whether the expression of target genes was dependent on galectin-3 levels. Results: rs4644 AA genotype was associated with a reduced risk of DTC (compared with CC, OR adj = 0.66; 95% confidence interval = 0.46-0.93; P ass = 0.02). We found that rs4644 affects galectin-3 as a transcriptional coregulator. Among 34 genes affected by rs4644, HES1 , HSPA6 , SPC24 , and NHS were of particular interest since their expression was rs4644-dependent (CC>AA for the first and AA>CC for the others), also in 574 thyroid tissues of Genotype-Tissue Expression (GTEx) biobank. Moreover, the expression of these genes was regulated by LGALS3 -silencing. Using the proximity ligation assay in Nthy-Ori cells, we found that the TTF-1 interaction was genotype dependent. Conclusions: Our data show that in thyroid, rs4644 is a trans-expression quantitative trait locus that can modify the transcriptional expression of downstream genes, through the modulation of TTF-1. |
