miR-29a inhibits proliferation, invasion, and migration of papillary thyroid cancer by targeting DPP4

Blood leukocytes as a non-invasive diagnostic tool for thyroid nodules: a prospective cohort study

BACKGROUND

Thyroid nodule (TN) patients in China are subject to overdiagnosis and overtreatment. The implementation of existing technologies such as thyroid ultrasonography has indeed contributed to the improved diagnostic accuracy of TNs. However, a significant issue persists, where many patients undergo unnecessary biopsies, and patients with malignant thyroid nodules (MTNs) are advised to undergo surgery therapy.

METHODS

This study included a total of 293 patients diagnosed with TNs. Differential methylation haplotype blocks (MHBs) in blood leukocytes between MTNs and benign thyroid nodules (BTNs) were detected using reduced representation bisulfite sequencing (RRBS). Subsequently, an artificial intelligence blood leukocyte DNA methylation (BLDM) model was designed to optimize the management and treatment of patients with TNs for more effective outcomes.

RESULTS

The DNA methylation profiles of peripheral blood leukocytes exhibited distinctions between MTNs and BTNs. The BLDM model we developed for diagnosing TNs achieved an area under the curve (AUC) of 0.858 in the validation cohort and 0.863 in the independent test cohort. Its specificity reached 90.91% and 88.68% in the validation and independent test cohorts, respectively, outperforming the specificity of ultrasonography (43.64% in the validation cohort and 47.17% in the independent test cohort), albeit with a slightly lower sensitivity (83.33% in the validation cohort and 82.86% in the independent test cohort) compared to ultrasonography (97.62% in the validation cohort and 100.00% in the independent test cohort). The BLDM model could correctly identify 89.83% patients whose nodules were suspected malignant by ultrasonography but finally histological benign. In micronodules, the model displayed higher specificity (93.33% in the validation cohort and 92.00% in the independent test cohort) and accuracy (88.24% in the validation cohort and 87.50% in the independent test cohort) for diagnosing TNs. This performance surpassed the specificity and accuracy observed with ultrasonography. A TN diagnostic and treatment framework that prioritizes patients is provided, with fine-needle aspiration (FNA) biopsy performed only on patients with indications of MTNs in both BLDM and ultrasonography results, thus avoiding unnecessary biopsies.

CONCLUSIONS

This is the first study to demonstrate the potential of non-invasive blood leukocytes in diagnosing TNs, thereby making TN diagnosis and treatment more efficient in China.

Hypoxic papillary thyroid carcinoma cells-secreted exosomes deliver miR-221-3p to normoxic tumor cells to elicit a pro-tumoral effect by regulating the ZFAND5

Papillary thyroid cancer (PTC) has seen a worldwide expansion in incidence in the past three decades. Tumor-derived exosomes have been associated with the metastasis of cancer cells and are present within the local hypoxic tumor microenvironment, where they mediate intercellular communication by transferring molecules including microRNAs (miRNAs) between cells. Although miRNAs have been shown to serve as non-invasive biomarkers for cancer diagnosis, the role of hypoxia-induced tumor-derived exosomes in PTC progression remains unclear. Herein, we investigated the differentially expressed miRNA expression profiles from GEO datasets (GSE191117 and GSE151180) by using the DESeq package in R and identified a novel role for miR-221-3p as an oncogene in PTC development. In vivo and in vitro loss and gain assays were used to clarify the mechanism of hypoxic PTC cells derived exosomal-miR-221-3p in PTC. miR-221-3p was upregulated in human PTC plasma exosomes, tissues and cell lines. We found that hypoxic PTC cells derived exosomal-miR-221-3p promoted normoxic PTC cells proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in vitro, while inhibition of miR-221-3p limited PTC tumor growth in our PTC xenograft model in nude mice. We finally identified ZFAND5, to be a miR-221-3p target. Mechanistically, hypoxic PTC cell lines-derived exosomes carrying miR-221-3p promoted PTC tumorigenesis by regulating ZFAND5. Our findings further the understanding of the underlying mechanisms associated with PTC progression and identify exosomal-miR-221-3p as a potential biomarker for the diagnosis and prognosis of PTC patients. Our study also suggests that miR-221-3p inhibitors could be a potential treatment strategy for PTC.

MiR-29a-3p: a potential biomarker and therapeutic target in colorectal cancer

Cancer is frequently caused by microRNAs, which control post-transcriptional levels of gene expression by binding to target mRNAs. MiR-29a-3p has recently been shown to play a twofold function in the majority of malignancies, including colorectal cancer (CRC), according to mounting evidence. Here, we not only briefly summarize such connection between miR-29a-3p and cancers, but aslo primarily evaluate the miR-29a-3p expression pattern, clinical applicability, and molecular mechanisms in CRC to provide a guide for future studies. This review established the diagnostic and prognostic value of miR-29a-3p abnormalty in a variety of clinical samples for CRC. Furthermore, current molecular mechanisms of miR-29a-3p for regulating cancerous biological processes such growth, invasion, metastasis, the epithelial-mesenchymal transformation process, and immunomodulation through its upstream regulatory factors and downstream targeted genes were briefly explored. More specifically, miR-29a-3p has been linked to a few medications that have been shown to have anticancer benefits. To sum up, miR-29a-3p is a promising biomarker and prospective therapeutic target for the diagnosis and prognosis of CRC, but further research is still needed to establish a theoretical basis for more practical applications.

Long noncoding RNA SNHG7-miRNA-mRNA axes crosstalk with oncogenic signaling pathways in human cancers

LncRNAs and miRNAs are the two most important non-coding RNAs, which have been identified to be associated with cancer progression or prevention. The dysregulation of lncRNAs conducts tumorigenesis and metastasis in different ways. One of the mechanisms is that lncRNAs interact with miRNAs to regulate distinct cellular and genomic processes and cancer progression. LncRNA SNHG7 as an oncogene sponges miRNAs and develops lncRNA-miRNA-mRNA axes, leading to the regulation of several signaling pathways such as Wnt/β-Catenin, PI3K/AKT/mTOR, SIRT1, and Snail-EMT. Therefore, in this article, after a brief overview of lncRNA SNHG7-miRNA-mRNA axes' contribution to cancer development, we will discuss the role of lncRNA SNHG7 in the genes expression and signaling pathways related to cancers development via acting as a ceRNA.

DPP4 gene silencing inhibits proliferation and epithelial-mesenchymal transition of papillary thyroid carcinoma cells through suppression of the MAPK pathway

PURPOSE

Papillary thyroid carcinoma (PTC) is characterized by epithelial malignancy and is the most prevalent thyroid neoplasm with the best overall prognosis. Notably, recently published studies have indicated remarkably high expression of dipeptidyl peptidase 4 (DPP4) in PTC. However, the underlying molecular mechanism and regulatory factors of PTC progression remain unknown. Therefore, the current study aimed to elucidate the effects of DPP4 gene silencing on PTC and further investigated whether the mechanism of PTC progression is related to the mitogen-activated protein kinase (MAPK) pathway.

METHODS

Herein, microarray-based gene expression profiling of PTC was conducted to identify the differentially expressed genes between tumor thyroid tissue and normal thyroid tissue as well as the underlying signaling pathway involved in PTC pathogenesis. Moreover, protein quantification was performed to assess the protein expression of DPP4 in PTC tissues collected from 65 patients. In addition, DPP4 was silenced in PTC cell lines (GLAG-66 and TPC-1) through siRNA-mediated DPP4 knockdown or sitagliptin (inhibitor of DPP4)-mediated inhibition to assess the effects of DPP4 on the MAPK pathway and cellular processes, including proliferation, apoptosis, and epithelial-to-mesenchymal transition (EMT).

RESULTS

Intriguingly, our data revealed markedly high expression of DPP4 in PTC tissues. However, in GLAG-66 and TPC-1 cells, the silencing of DPP4 resulted in significantly reduced expression of ERK1/2, JNK1, P38 MAPK, VEGF, FGFR-1, TGF-β1, Snail, HIF-1α, N-cadherin, and Bcl-2 along with reduced phosphorylation of ERK1/2, JNK1, and P38 MAPK, whereas the expression of E-cadherin and Bax was increased. Furthermore, DPP4 silencing was found to hinder cell proliferation and potentiate cell apoptosis.

CONCLUSION

Collectively, the present study demonstrated that DPP4 gene silencing inhibits PTC cell proliferation and EMT and promotes cell apoptosis via suppression of the MAPK pathway, thus highlighting a possible regulatory pathway in PTC progression.

A Ferroptosis-Related Signature Robustly Predicts Clinical Outcomes and Associates With Immune Microenvironment for Thyroid Cancer

Objective: This study aimed to construct a prognostic ferroptosis-related signature for thyroid cancer and probe into the association with tumor immune microenvironment.

Methods: Based on the expression profiles of ferroptosis-related genes, a LASSO cox regression model was established for thyroid cancer. Kaplan-Meier survival analysis was presented between high and low risk groups. The predictive performance was assessed by ROC. The predictive independency was validated via multivariate cox regression analysis and stratified analysis. A nomogram was established and verified by calibration curves. The enriched signaling pathways were predicted via GSEA. The association between the signature and immune cell infiltration was analyzed by CIBERSORT. The ferroptosis-related genes were validated in thyroid cancer tissues by immunohistochemistry and RT-qPCR.

Results: A ferroptosis-related eight gene model was established for predicting the prognosis of thyroid cancer. Patients with high risk score indicated a poorer prognosis than those with low risk score (p = 1.186e-03). The AUCs for 1-, 2-, and 3-year survival were 0.887, 0.890, and 0.840, respectively. Following adjusting other prognostic factors, the model could independently predict the prognosis (p = 0.015, HR: 1.870, 95%CI: 1.132–3.090). A nomogram combining the signature and age was constructed. The nomogram-predicted probability of 1-, 3-, and 5-year survival approached the actual survival time. Several ferroptosis-related pathways were enriched in the high-risk group. The signature was distinctly associated with the immune cell infiltration. After validation, the eight genes were abnormally expressed between thyroid cancer and control tissues.

Conclusion: Our findings established a prognostic ferroptosis-related signature that was associated with the immune microenvironment for thyroid cancer.

Roles of the SNHG7/microRNA‑9‑5p/DPP4 ceRNA network in the growth and 131I resistance of thyroid carcinoma cells through PI3K/Akt activation

Radioactive iodine (RAI, ¹³¹I) therapy is the main treatment for thyroid carcinoma (TC). Long noncoding RNA (lncRNA)/microRNA (miR) competing endogenous RNA (ceRNA) networks have aroused great interest for their roles in gene expression. The present study aimed to investigate the effect of lncRNA SNHG7 on the growth and ¹³¹I resistance of TC. Differentially expressed lncRNAs in TC and paracancerous tissues were analyzed. The binding of miR-9-5p with small nucleolar RNA host gene 7 (SNHG7) and dipeptidyl-peptidase 4 (DPP4) was identified. Gain- and loss-of-function analyses of SNHG7 and miR-9-5p were performed to determine their effects on the growth and ¹³¹I resistance of TC cells. The activity of the PI3K/Akt pathway was evaluated. Consequently, upregulated SNHG7 was revealed in TC tissues and correlated with ¹³¹I resistance. Silencing of SNHG7 or overexpressing miR-9-5p inhibited the growth and ¹³¹I resistance of TC cells. SNHG7 acted as a ceRNA of miR-9-5p to enhance DPP4 expression. Overexpressed SNHG7 increased DPP4 expression and activated the PI3K/Akt signaling pathway by sponging miR-9-5p. The in vitro results were reproduced in vivo. In summary, the present study provided evidence that the SNHG7/miR-9-5p/DPP4 ceRNA network could promote the growth and ¹³¹I resistance of TC cells via PI3K/Akt activation. The present study may offer novel options for TC treatment.

MicroRNA-29a inhibits cell proliferation and arrests cell cycle by modulating p16 methylation in cervical cancer

Cervical cancer is the second most common gynecological malignancy. Accumulating evidence has suggested that microRNAs (miRNAs) are involved in the occurrence and development of cervical cancer. The present study aimed to investigate the function and underlying molecular mechanism of microRNA (miRNA/miR)-29a in cervical cancer. Reverse transcription-quantitative PCR and methylation-specific PCR were used to examine the expression of miR-29a and methylated status of p16 promoter, respectively. Cell Counting Kit-8 analysis and flow cytometry were performed to evaluate cell viability and cycle, respectively. Dual-luciferase reporter assay was performed to verify the interaction between miR-29a and its targets. Western blot analysis was performed to detect the protein levels of DNA methyltransferases (DNMT)3A and DNMT3B. The results demonstrated that miR-29a expression was downregulated in cervical cancer tissues and cells, and negatively correlated with p16 promoter hypermethylation. Furthermore, cell experiments confirmed that miR-29a suppressed cell proliferation and induced cell cycle arrest in HeLa and C-33A cells. Mechanically, miR-29a restored normal methylation pattern of the p16 gene by sponging DNMT3A and DNMT3B. Taken together, the results of the present study demonstrated the epigenetic regulation of tumor suppressor p16 by miR-29a as a unique mechanism, thus providing a rationale for the development of miRNA-based strategies in the treatment of cervical cancer.

Decreased serum exosomal miR-29a expression and its clinical significance in papillary thyroid carcinoma

Background

Aberrant levels of circulating microRNAs (miRNAs) are potential biomarkers in papillary thyroid carcinoma (PTC) diagnosis and therapy. The aim of this study was to evaluate serum exosomal miR‐29a expression as a non‐invasive biomarker for PTC diagnosis and prognosis.

Methods

Quantitative reverse transcription polymerase chain reaction was applied to measure serum exosomal miR‐29a expression levels in blood samples of 119 patients with PTC and 100 control subjects.

Results

Serum exosomal miR‐29a expression levels were significantly decreased in PTC cases. In addition, receiver operating characteristic (ROC) analysis revealed serum exosomal miR‐29a could well differentiate PTC from normal controls. Moreover, serum exosomal miR‐29a levels increased progressively and significantly 30 days and 90 days after surgery. Furthermore, PTC patients with lower serum exosomal miR‐29a expression had higher risk of recurrence. Decreased serum exosomal miR‐29a expression was significantly associated with worse clinical variables including tumor size, extrathyroidal extension, and TNM stage, as well as shorter survival. Finally, both univariate and multivariate identified serum exosomal miR‐29a as an independent prognostic indicator for overall survival.

Conclusion

These results demonstrated that serum exosomal miR‐29a might serve as a potential biomarker for PTC diagnosis and prognosis.

Mesenchymal stem cells-originated exosomal microRNA-152 impairs proliferation, invasion and migration of thyroid carcinoma cells by interacting with DPP4

BACKGROUND

Thyroid carcinoma (THCA) is the most prevalent tumor in the endocrine system with an increasing incidence. Recent studies have underscored the function of microRNAs (miRNAs) in THCA. Nevertheless, knowledge regarding the effects of exosomal miRNAs in THCA is still limited. This report intended to probe the regulatory effects of exosomal miR-152 on THCA and the underlying mechanism.

METHODS

The expression profile of miR-152 was studied in clinical samples as well as B-CPAP and TPC-1 cells. Transwell, CCK-8, and flow cytometric assays were performed to investigate the roles of miR-152 on invasion, migration, proliferation, and apoptosis in B-CPAP and TPC-1 cells. The putative target of miR-152 was predicted using the bioinformatic analysis, and the targeting relationship was confirmed verified subsequently. Afterward, exosomes were isolated from bone marrow mesenchymal stem cells (BM-MSCs) and co-cultured with B-CPAP and TPC-1 cells to explore the function of exosomal miR-152 on THCA cells.

RESULTS

miR-152 was reduced in THCA tissues and cells. Restoration of miR-152 inhibited proliferation, invasion and migration of B-CPAP and TPC-1 cells, but promoted cell apoptosis. Dipeptidyl dipeptidase 4 (DPP4), a target of miR-152, was found to promote THCA cell invasion and migration. miR-152 ferried by BM-MSCs-derived exosomes repressed THCA cell invasion and migration, and pcDNA-DPP4 weakened the repression effect.

CONCLUSION

Exosomal miR-152 inhibited proliferation, migration and invasion of THCA cells by binding with DPP4, which may represent a novel target for the treatment of THCA.

LncRNA TUG1 Promotes Growth and Metastasis of Cholangiocarcinoma Cells by Inhibiting miR-29a

Background

As a highly malignant tumor, cholangiocarcinoma poses a serious threat to human life and health, so exploring the mechanisms of its development and progression at a molecular level is of great significance to the diagnosis and treatment of the disease.

Objective

This study was aimed at investigating the effects and related mechanisms of LncRNA TUG1 on cholangiocarcinoma cells.

Methods

Cholangiocarcinoma tissues and adjacent tissues (n=82 each), human cholangiocarcinoma cell lines (RBE, QBC939, HuH28), and a human normal biliary epithelial cell line (HIBE) were collected. miR-29a-mimics, miR-29a-inhibitor, miR-NC, si-TUG1, pcDNA3.1 TUG1, and NC were transfected into the cholangiocarcinoma cells. qRT-PCR was performed to detect TUG1 and miR-29a expression in the cholangiocarcinoma tissues and cells. Western blotting (WB) was conducted to detect the expression of Bax, Caspase-3, and Bcl-2 in the cells. CCK-8 assay, Transwell, and flow cytometry were carried out to detect cell proliferation, invasion, and apoptosis. Dual luciferase reporter gene assay (DLRGA) was performed to confirm the correlation of TUG1 with miR-29a.

Results

TUG1 was highly expressed while miR-29a was poorly expressed in cholangiocarcinoma cells. TUG1 expression was negatively correlated with miR-29a expression, and TUG1 had a relatively high diagnostic value for cholangiocarcinoma. Cell experiments showed that inhibiting TUG1 expression or up-regulating miR-29a expression could inhibit cholangiocarcinoma cells from proliferation and invasion, and promote their apoptosis, while up-regulating TUG1 or inhibiting miR-29a could promote the proliferation and invasion but inhibit the apoptosis. Rescue experiment showed that overexpressing miR-29a could reverse the effects of high TUG1 expression on cholangiocarcinoma cells. DLRGA confirmed that there was a regulatory relationship between TUG1 and miR-29a.

Conclusion

TUG1 is highly expressed in cholangiocarcinoma tissues. It can promote the growth and metastasis of cholangiocarcinoma cells by inhibiting miR-29a, so it may be a new target for diagnosing and treating cholangiocarcinoma.

FosB recruits KAT5 to potentiate the growth and metastasis of papillary thyroid cancer in a DPP4-dependent manner

OBJECTIVE

Dipeptidyl peptidase IV (DPP4) has been indicated as a possible prognostic biomarker in papillary thyroid cancer (PTC). However, the mechanism of DPP4 during metastasis of PTC remains unclear. In this study, we investigated whether lysine acetyltransferase 5 (KAT5) and FBJ murine osteosarcoma viral oncogene homolog B (FosB) synergistically regulate high DPP4 expression in PTC.

METHODS

PTC tissues and matched paracancerous tissues were harvested, followed by the establishment of IHH-4 and TPC-1 cells with downregulation of DPP4. The relevance of DPP4 on the metastasis of PTC cells was assessed. Subsequently, the effect of KAT5 on the transcription of DPP4 was verified. The binding relationship between FosB and DPP4 was predicted by a bioinformatics website. Functional rescue experiments were performed to evaluate cell activities after overexpression of KAT5 or FosB in cells with DPP4 knockdown.

RESULTS

DPP4 was overexpressed in PTC tissues and cell lines, which was correlated with higher risks for metastases and poorer survival. DPP4 downregulation curtailed cell growth and metastasis. Moreover, KAT5 acetylated DPP4 promoter histone, which promoted transcription activation of DPP4. Subsequently, FosB recruited KAT5 at the DPP4 promoter, thereby enhancing DPP4 transcriptional activation. Further overexpression of KAT5 or FosB in cells with low expression of DPP4 promoted cell activity. Finally, DPP4 expedited p62 nuclear translocation to elevate Keap1/Nrf2 expression, thus facilitating the growth and metastasis of PTC cells.

CONCLUSION

FosB enhanced the growth and metastasis of PTC cells by recruiting histone acetyltransferases KAT5 to increase DPP4 transcription and activate the p62/Keap1/Nrf2 signaling.