Related Experiment Video
Updated: Oct 23, 2025
In Vivo Inhibition of MicroRNA to Decrease Tumor Growth in Mice
Published on: August 23, 2019
New evidence on tumor suppressor activity of PTEN and KLLN in papillary thyroid carcinoma
S Adeleh Razavi1, Pouya Salehipour2, Hanieh Gholami1
1Cellular and Molecular Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, No. 23, Shahid Arabi St. Yemen St. Velenjak, PO Box: 19395-4763, Tehran, Iran.
Abstract:
This study aimed to address the hypothesis that the expression of PTEN and KLLN tumor suppressor genes could diminish in papillary thyroid cancer (PTC) compared to paired normal tissue (PNT) and multinodular goiter (MNG). PTEN and KLLN expressions were assessed at both mRNA and protein levels in 82 tissue samples, including 30 PTC, 30 PNT, and 26 MNG using SYBR-Green Real-Time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. Bioinformatics studies were performed to evaluate the genomic location and the genes promoter region. The mRNA expression of PTEN and KLLN in PTC was significantly lower than PNT (PTEN, P = 0.0033; KLLN, P = 0.0005). A significant decrease in the mRNA level of KLLN was also observed in PTC than MNG (P = 0.0304). Decreased level of PTEN mRNA (odds ratio=0.391; P = 0.013) or KLLN mRNA (odds ratio=0.023; P = 0.025) was associated with an increased risk of PTC tumorigenesis. Areas under the ROC curve for PTEN and KLLN were 0.69 and 0.78, respectively. PTEN and KLLN protein expressions in PTC compared to PNT or MNG were not significantly different. The bioinformatics studies revealed the sequence near the promoter region is lowly conserved across species. Four GC boxes were found upstream of the PTEN transcription start site (TSS), and one TATA box and one GC box were found upstream of KLLN TSS. The results suggest PTEN and KLLN are the two tumor suppressor genes that decreasing or loss of both of them occurs in sporadic PTC tumorigenesis. It appears they could have a promising application in both diagnostic and therapeutic areas.
Related Concept Videos
02:23Abnormal Proliferation
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
01:12Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
01:17Hormones and Bone Tissue
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
02:34Inhibition of Cdk Activity
01:20The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...