SOX18 exerts tumor-suppressive functions in papillary thyroid carcinoma through inhibition of Wnt/β-catenin signaling

Colchicine inhibits the proliferation and promotes the apoptosis of papillary thyroid carcinoma cells likely due to the inhibitory effect on HDAC1

Although the prognosis for papillary thyroid carcinoma (PTC) is generally good, a certain proportion of patients show recurrent or advanced disease, indicating the need for further development of targeted medications. The purpose of this study was to explore the interventional effects of colchicine on PTC and the potential mechanisms or targets. We obtained PTC-related targets from the database and colchicine targets by predicting them. We screened the common targets of colchicine and the PTC-related target histone deacetylase 1 (HDAC1) and verified through molecular docking that colchicine has a good affinity for HDAC1, i.e., colchicine may act on PTC by affecting HDAC1. We then used CCK-8, colony formation, mitochondrial membrane potential and apoptosis assays to confirm that colchicine could inhibit the proliferation and promote the apoptosis of PTC cells and verified by RT‒qPCR, Western blot, and cellular immunofluorescence assays that colchicine could inhibit the expression of HDAC1 in PTC cells. The cytotoxicity and inhibitory effect of colchicine on HDAC1 in PTC cells was stronger than that in normal thyroid cells. We then applied an HDAC1 inhibitor, pyroxamide, to verify that inhibition of HDAC1 inhibits proliferation and promotes apoptosis in PTC cells. Therefore, we conclude that colchicine can inhibit the proliferation and promote the apoptosis of PTC cells likely due to its inhibitory effect on HDAC1. This finding implies that colchicine may be helpful for therapeutic intervention in PTC and that HDAC1 may be a promising clinical therapeutic target.

Targeting SOX18 Transcription Factor Activity by Small-Molecule Inhibitor Sm4 in Non-Small Lung Cancer Cell Lines

The transcription factor SOX18 has been shown to play a crucial role in lung cancer progression and metastasis. In this study, we investigated the effect of Sm4, a SOX18 inhibitor, on cell cycle regulation in non-small cell lung cancer (NSCLC) cell lines LXF-289 and SK-MES-1, as well as normal human lung fibroblast cell line IMR-90. Our results demonstrated that Sm4 treatment induced cytotoxic effects on all three cell lines, with a greater effect observed in NSCLC adenocarcinoma cells. Sm4 treatment led to S-phase cell accumulation and upregulation of p21, a key regulator of the S-to-G2/M phase transition. While no significant changes in SOX7 or SOX17 protein expression were observed, Sm4 treatment resulted in a significant upregulation of SOX17 gene expression. Furthermore, our findings suggest a complex interplay between SOX18 and p21 in the context of lung cancer, with a positive correlation observed between SOX18 expression and p21 nuclear presence in clinical tissue samples obtained from lung cancer patients. These results suggest that Sm4 has the potential to disrupt the cell cycle and target cancer cell growth by modulating SOX18 activity and p21 expression. Further investigation is necessary to fully understand the relationship between SOX18 and p21 in lung cancer and to explore the therapeutic potential of SOX18 inhibition in lung cancer.

SNRPB promotes cell cycle progression in thyroid carcinoma via inhibiting p53

Papillary thyroid carcinoma (PTC) accounts for more than 80% of all thyroid carcinoma cases. Small nuclear ribonucleoprotein polypeptides B and B1 (SNRPB) has been indicated to be carcinogenic in several cancers; however, its function and mechanism in PTC are unclarified. Real time quantitative polymerase chain reaction and western blotting revealed the upregulation of SNRPB and downregulation of tumor protein p53 in PTC tissues compared with the normal tissues. Flow cytometry and western blotting displayed that SNRPB silencing induced cell cycle arrest at G1 phase and suppressed the expression levels of Cyclin family proteins in PTC cells. In vivo experiments suggested that SNRPB silencing inhibited PTC tumor growth in mice. Bioinformatics analysis revealed that the expression of SNRPB and cell cycle-associated genes in thyroid carcinoma tissues is positively correlated. Immunofluorescence staining and co-immunoprecipitation demonstrated that SNRPB directly interacted with p53 and suppressed its expression in PTC cells. In conclusion, SNRPB facilitates cell cycle progression in PTC by inhibiting p53 expression.

A ceRNA network mediated by LINC00475 in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is the most frequent histological type of differentiated thyroid carcinoma. Long noncoding RNAs (lncRNAs) have been widely reported to play a key role in human malignancies, and PTC is included. This study aimed to find out the functions and mechanism of lncRNA LINC00475 in PTC. LINC00475 was upregulated in PTC cells and was mainly located in the cytoplasm according to reverse-transcription polymerase chain reaction analyses and subcellular fractionation assays. As shown by cell counting kit-8 assays, ethynyl deoxyuridine incorporation assays, wound healing assays, and transwell assays, LINC00475 knockdown suppressed cell viability, proliferation, migration, and invasion. Mechanistically, LINC00475 upregulated the expression of messenger RNA zinc finger CCHC-type containing 12 (ZCCHC12) by binding to miR-376c-3p. ZCCHC12 was a direct target gene of miR-376c-3p in PTC cells. The relationship between miR-376c-3p and LINC00475 (or ZCCHC12) in PTC cells was probed by luciferase reporter assays, RNA pulldown assays, and RNA immunoprecipitation assays. In addition, both mRNA and protein levels of ZCCHC12 were downregulated due to miR-376c-3p overexpression or LINC00475 silencing. ZCCHC12 overexpression partially reversed the suppressive effect of LINC00475 knockdown on malignant behaviors of PTC cells. In conclusion, LINC00475 promotes PTC cell proliferation, migration, and invasion by upregulating ZCCHC12 via the interaction with miR-376c-3p.

The Emerging Landscapes of Long Noncoding RNA in Thyroid Carcinoma: Biological Functions and Clinical Significance

Thyroid carcinoma (TC) is one of the most prevalent primary endocrine tumors, and its incidence is steadily and gradually increasing worldwide. Accumulating evidence has revealed the critical functions of long noncoding RNAs (lncRNAs) in the tumorigenesis and development of TC. Many TC-associated lncRNAs have been documented to be implicated in TC malignant behaviors, including abnormal cell proliferation, enhanced stem cell properties and aggressiveness, and resistance to therapeutics, through interaction with proteins, DNA, or RNA or encoding small peptides. Therefore, further elucidating the lncRNA dysregulation sheds additional insights into TC tumorigenesis and progression and opens new avenues for the early diagnosis and clinical therapy of TC. In this review, we summarize the abnormal expression of lncRNA in TC and the fundamental characteristics in TC tumorigenesis and development. Additionally, we introduce the potential prognostic and therapeutic significance of lncRNAs in TC.

SOX18 enhances the proliferation and migration of airway smooth muscle cells induced by tumor necrosis factor-α via the regulation of Notch1 signaling

Childhood asthma is a frequent chronic disease of pediatric populations. The excessive proliferation and migration of airway smooth muscle cells contribute to airway remodeling during asthma pathogenesis. Sex-determining region on the Y chromosome-related high mobility group box 18 (SOX18) has been reported to be over-expressed in asthma. However, whether SOX18 plays a role in modulating the airway remodeling of asthma is not fully understood. The purposes of this work were to assess the potential role of SOX18 in modulating airway remodeling using tumor necrosis factor-α (TNF-α)-stimulated airway smooth muscle cells in vitro. Our results showed that SOX18 expression was increased following TNF-α stimulation in airway smooth muscle cells. The silencing of SOX18 markedly prohibited the proliferation and migration of airway smooth muscle cells induced by TNF-α, whilst the over-expression of SOX18 produced the opposite effects. Further investigation revealed that SOX18 promoted the expression of Notch1, and enhanced the activation of Notch1 signaling in airway smooth muscle cells stimulated by TNF-α. The inhibition of Notch1 markedly diminished SOX18-over-expression-evoked promotion effects on TNF-α-induced proliferation and migration of airway smooth muscle cells. In addition, the reactivation of Notch1 signaling markedly reversed the SOX18-silencing-induced suppressive effect on the TNF-α-induced proliferation and the migration of airway smooth muscle cells. In summary, the findings of this work demonstrate that SOX18 regulates the proliferation and migration of airway smooth muscle cells induced by TNF-α via the modulation of Notch1 signaling. This study indicates a potential role for SOX18 in promoting airway remodeling during asthma pathogenesis.