Osteoporosis is a severe chronic skeletal disorder that affects older individuals, especially postmenopausal women. However, molecular biomarkers for predicting the risk of osteoporosis are not well characterized. The aim of this study was to identify combined biomarkers for predicting the risk of osteoporosis using machine learning methods.
View Article and Find Full Text PDFUterine leiomyoma is a benign smooth muscle tumor of the uterus that can exhibit histopathological traits that mimic malignancy. Telomere shortening is an early event in tumorigenesis and telomerase activation facilitates tumor progression later in the course of carcinogenesis. Telomeric repeat‑binding factor () and protect telomeres, and their gene expression levels are dysregulated in various cancer types.
View Article and Find Full Text PDFTelomeric repeat-containing RNAs (TERRAs) are long noncoding RNAs transcribed from subtelomeres toward telomeric repeat tracts, which have been implicated in telomere protection and heterochromatin formation. Genotoxic stress leads to upregulation of TERRAs. However, the mechanism of DNA damage-mediated TERRA induction remains elusive.
View Article and Find Full Text PDFTelomeres are transcribed into long non-coding RNA, referred to as telomeric repeat-containing RNA (TERRA), which plays important roles in maintaining telomere integrity and heterochromatin formation. TERRA has been well characterized in HeLa cells, a type of cervical cancer cell. However, TERRA abundance and stability have not been examined in other cervical cancer cells, at least to the best of our knowledge.
View Article and Find Full Text PDF() utilizes two different cell-cycle modes, binucleations during the L1 larval stage and endoreduplications at four larval moltings, for its postembryonic intestinal development. Previous genetic studies indicated that CDC-25.2 is specifically required for binucleations at the L1 larval stage and is repressed before endoreduplications.
View Article and Find Full Text PDFPinX1, a nucleolar protein of 328 amino acids, inhibits telomerase activity, which leads to the shortening of telomeres. The C-terminal region of PinX1 is responsible for its nucleolar localization and binding with TERT, a catalytic component of telomerase. A fraction of TERT localizes to the nucleolus, but the role of TERT in the nucleolus is largely unknown.
View Article and Find Full Text PDFTRF1, a telomere-binding protein, is important for telomere protection and homeostasis. PinX1 interacts with TRF1, but the physiological consequences of their interaction in telomere protection are not yet understood. Here we investigated PinX1 function on TRF1 stability in HeLa cells.
View Article and Find Full Text PDFBackground & Aims: Hepatocellular carcinomas (HCCs) expressing "stemness"-related markers have been associated with aggressive biological behavior and poor prognosis. We examined the relationship between "stemness"-related protein expression and telomere length, hTERT and shelterin complex protein expression and chromosomal instability.
Methods: Quantitative fluorescent in situ hybridization for telomere length, immunohistochemistry for K19, EpCAM, CD133, c-kit, HepPar1, hTERT, TRF1, TRF2, POT1, RAP1 and TPP1, and TUNEL assay were performed in 137 HCCs, and array comparative genomic hybridization was performed with 24 HCCs.
Human immortal cells maintain their telomeres either by telomerase or by alternative lengthening of telomeres (ALT) that is based on homologous telomeric recombination. Previous studies showed that the ALT mechanism is activated in non-ALT cells when heterochromatic features are reduced. In this study, we examined the ALT phenotypes of ALT cells after treatment with trichostatin-A (TSA), which is an inhibitor of histone deacetylases and causes global chromatin decondensation.
View Article and Find Full Text PDFBackground/aims: Epigenetic regulations play a role in the development and progression of cancer. Therefore, discovering novel epigenetically regulated genes could provide useful information in understanding cancer. Lamin A/C is an intermediate filament protein whose expression is reported to be suppressed in tissues of gastro-intestinal malignancies.
View Article and Find Full Text PDFBackground & Aims: The concept of multistep hepatocarcinogenesis has been well-established, and an accumulation of methylating events has recently been demonstrated; however, the methylation status of low-grade dysplastic nodules (LGDN), high-grade dysplastic nodules (HGDN), and the recently introduced early hepatocellular carcinoma (eHCC) in hepatitis B virus (HBV)-related hepatocarcinogenesis has not yet been studied.
Methods: One hundred thirty-three DNA samples (45 cirrhotic nodules, 29 LGDNs, 13 HGDNs, 14 eHCCs, and 32 progressed HCCs (pHCCs)) from HBV-infected resected livers were subjected to MethyLight analysis for nine CpG island loci (APC, RASSF1A, SOCS1, P16, COX2, SPRY2, PTEN, GNMT, and ERK), and COX2, RASSF1A, and SOCS1 protein expression status was analyzed by immunohistochemistry. The methylation status of each sample was correlated with the clinicopathological features.
Hepatocellular carcinomas (HCCs) with expression of stem/progenitor cell markers including CD133 have been reported to have more aggressive biological behavior, and epithelial-mesenchymal transition (EMT), closely related invasion, has been suggested to generate cancer stem cells. To elucidate biological characteristics of HCCs expressing CD133, we evaluated migration assay and the mRNA expression levels of CD133, invasion-associated genes [urokinase plasminogen activator receptor (uPAR), villin 2 (VIL2), and MMP1 and MMP2], and EMT regulators (Snail, Slug, Twist, E-cadherin, and N-cadherin) by real-time PCR in HCC cell lines including HepG2, Hep3B, Huh7, PLC/RFP/6, SNU423, SNU449, and SNU475. Same genes and pathological features were also investigated in 49 samples of hepatitis B virus-related human HCCs.
View Article and Find Full Text PDFTreatment of Caenorhabditis elegans with apigenin, 5,7,4'-trihydroxyflavone, induces larval growth inhibition. To understand the molecular basis of apigenin-induced larval growth inhibition, the effects of apigenin on DAF-16 activity were examined. DAF-16 was activated through nuclear translocation and the mRNA level of sod-3, one of the known DAF-16 target genes, was increased upon apigenin treatment.
View Article and Find Full Text PDFSubtelomeric chromatin modifications are important regulators of telomere length. We examined the subtelomeric DNA methylation status of 7q, 8q, 17q, 18p, 21q and XpYp in 32 pairs of hepatocellular carcinomas (HCCs) and their adjacent non-HCCs via methylation-specific PCR (quantified as methylation ratio). In addition, 10q was subjected to bisulfite-genomic-sequencing.
View Article and Find Full Text PDFThe cdc25 gene, which is highly conserved in many eukaryotes, encodes a phosphatase that plays essential roles in cell cycle regulation. We identified a cdc25 ortholog in the pinewood nematode, Bursaphelenchus xylophilus. The B.
View Article and Find Full Text PDFUnlabelled: Large liver cell change (LLCC) refers to microscopic lesions often found in various chronic liver diseases; however, its nature is still controversial. Thirty-four formalin-fixed and 19 fresh frozen hepatitis B virus (HBV)-related cirrhosis samples were examined for the presence of LLCC, small liver cell change (SLCC), and hepatocellular carcinoma (HCC). The cell cycle checkpoint status (p21, p27, p16, Tp53), cell dynamics (proliferating cell nuclear antigen, Ki-67, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling, M30), DNA damage (gamma-H2AX [H2A histone family, member X]), telomere lengths, chromosomal instability (micronuclei index), and senescence-associated beta-galactosidase (SA-beta-Gal) activity were evaluated using an in situ approach and compared to those in normal liver (n = 5) and liver with chronic cholestasis (34 cases of hepatolithiasis and three cases of primary biliary cirrhosis).
View Article and Find Full Text PDFSystemic analysis for chromosomal instability and inactivation of cell cycle checkpoints are scarce during hepatocarcinogenesis. We studied 24 patients with chronic B viral cirrhosis including 30 cirrhotic regenerative nodules, 35 low-grade dysplastic nodules, 15 high-grade dysplastic nodules, 7 dysplastic nodules with hepatocellular carcinoma foci, and 18 hepatocellular carcinomas. Eight normal livers were studied as the control group.
View Article and Find Full Text PDFSubtelomeric epigenetic modifications are known to be associated with telomere length. We examined subtelomeric DNA methylation at seven sites for five chromosomes by methylation-specific PCR (MSP) and two sites for two chromosomes by bisulfite genomic sequencing (BGS) in 20 human cancer cell lines and subsequently analyzed their association with telomere length. Full-methylation (55/140) was more frequently found compared to un-methylation (35/140) (p=0.
View Article and Find Full Text PDFHuman PinX1 (hPinX1) is known to interact with telomere repeat binding factor 1 (TRF1) and telomerase. Here, we report that hPinX1 regulates the nucleolar accumulation and telomeric association of TRF1. In HeLa, HA-hPinX1 was co-localized with fibrillarin, a nucleolar protein, in 51% of the transfected cells and was present in the nucleoplasm of the remaining 48%.
View Article and Find Full Text PDFWe investigated the biological role of thymidine phosphorylase (TP), an angiogenic factor, in gastric cancer cell migration and invasion and explored a therapeutic approach for high TP-expressing tumors using TP enzymatic inhibitor (TPI) and rapamycin. We established TP cDNA overexpressing gastric cancer cell lines (MKN-45/TP and YCC-3/TP) and did invasion and adhesion assays with Matrigel-coated transwell membranes. The related signal pathway using recombinant human TP (rhTP), deoxy-d-ribose (D-dRib), and signal pathway inhibitors (wortmannin, LY294002, and rapamycin) was investigated.
View Article and Find Full Text PDFTelomeric 3' overhang is a key component of telomere structure, but little is known about its role in hepatocarcinogenesis. We examined the 3' overhang and telomere length, mRNA levels of hTERT, POT1, TRF1 and cytokeratin 19 (CK19) in 41 hepatitis B virus (HBV)-related hepatocellular carcinomas (HCCs) and adjacent non-HCCs of B viral chronic hepatitis/cirrhosis. 3' overhang length was positively correlated with telomere length (p < 0.
View Article and Find Full Text PDFThe telomeric G-rich 3' overhang is important for the maintenance of chromosomal integrity by stabilizing T-loop structure in which the 3' overhang invades the double-stranded telomeric DNA. However, the 3' overhang length has not been examined in different human cell lines, and its regulatory mechanism has not been revealed. In this study, we examined overhang length in 56 human cancerous cell lines and five normal cell lines, originated from various tissues.
View Article and Find Full Text PDFTelomerase reactivation and telomere maintenance are crucial in carcinogenesis and tumor progression. In this study, the relationships between telomere parameters, chromosomal instability and clinicopathological features were evaluated in hepatocellular carcinomas (HCCs). Telomere length (TL), telomerase activity (TA) and human telomerase reverse transcriptase (hTERT) mRNA levels were measured in 49 hepatitis B virus (HBV)-related HCCs and corresponding non-tumorous tissues.
View Article and Find Full Text PDFHuman PinX1 involves in regulation of telomere length. Here, we describe the function of a rat homolog of PinX1. Rat PinX1 (rPinX1) was cloned from WB-F344, a rat hepatic stem-like epithelial cell.
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