Expression and Clinical Significance of miR-26a and Pleomorphic Adenoma Gene 1 (PLAG1) in Invasive Pituitary Adenoma

Abstract

BackgroundAlthough pituitary adenoma is a malignant tumor, it can present as invasive growth in some cases. MicroRNA (miR)-26a has been found to be abnormally highly expressed in pituitary adenoma, indicating possible involvement in pathogenesis. As a known target gene of miR-26a, PLAG1 has abnormally low expression in pituitary adenoma. The correlation between miR-26a or PLAG1 expressional abnormality and occurrence of pituitary adenoma is still unknown, as is its association with invasiveness of pituitary adenoma.Material/MethodsPituitary adenoma tissues, including both invasive and non-invasive subtypes, were collected from our Neurosurgery Department, in parallel with normal pituitary tissues from postmortem autopsy. qRT-PCR was used to detect mRNA expression of miR-26a and PLAG1, while Western blotting was used to test PLAG1 protein expression. The correlation between miR-26a and PLAG1, and with pathological features, were analyzed. ROC analysis revealed the utility of miR-26a and PLAG1 in differential diagnosis of invasive/non-invasive pituitary tumors and in analyzing their effects on patient prognosis.ResultsMiR-26a was remarkably upregulated in pituitary tumors, while PLAG1 was downregulated, especially in invasive pituitary tumors. miR-26a and PLAG1 had higher diagnostic values for differentiating between invasive and non-invasive pituitary tumors (AUC=0.889 and 0.818, respectively). Those patients with miR-26 overexpression and PLAG1 downregulation had unfavorable prognosis. miR-26 and PLAG1 are independent factors affecting patient diagnosis.ConclusionsMiR-26a can facilitate occurrence of pituitary tumor and invasiveness, probably via inhibiting PLAG1 expression.

Downregulation of glucose‑6‑phosphate dehydrogenase by microRNA‑1 inhibits the growth of pituitary tumor cells

“…miRNAs function as key regulators of gene expression via binding to the 3'-untranslated region (UTR) of the target mRNAs, and consequently inducing the degradation or translation inhibition of the mRNAs (5,7,8). Notably, emerging evidence has illustrated the critical roles of miRNAs in the pathogenesis of different cancer types (9)(10)(11)(12)(13)(14)(15)(16). For example, miR-106b targeted the tumor suppressor phosphatase and tensin homolog and promoted the growth of pituitary cancer cells (17).…”

Increased miR‐323a induces bladder cancer cell apoptosis by suppressing c‐Met

“…In recent years, more and more evidences have shown that miRNA plays a key regulatory role in tumorigenesis and development. 5,7 For instance, miRNAs are found to affect cell differentiation, proliferation, and apoptosis by reducing the stability of target genes or inhibiting their translation. 27,28 Exploring the relationship between miRNAs and BC formation provides a new way to define the pathogenic factors of BC.…”

“…It is a family of noncoding regulatory RNAs with a 5‐terminal phosphoryl group and a 3‐terminal hydroxyl group and is approximately 22 nucleotides in length . More than 1/3 of all human genes are controlled by miRNA . Increasing evidence has suggested the important role of miRs in the progression of BC .…”

“…6 More than 1/3 of all human genes are controlled by miRNA. 7 Increasing evidence has suggested the important role of miRs in the progression of BC. 8,9 For instance, miR-206 is reported to be a tumor suppressor in BC via inhibiting the expression of YRDC.…”

A mikro-RNS-ek szerepe az agyalapimirigy-daganatok tumorbiológiájában

“…Egy miRNS-nek a bá-zispárosodás szabályai szerint több célgénje is van, és egy célmolekula kifejeződését számos miRNS is szabályoz-hatja. A biológiai funkciók hátterében álló mechanizmusokat a sejten belüli jelátviteli útvonalakkal lehet a leginkább jellemezni, így a miRNS-ek szabályozó szerepét nemcsak egy-egy génhez (1. táblázat) [34,42,[44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59], hanem egy-egy jelátviteli útvonalhoz is lehet rendelni.…”