Roles of circ_0000135/miR-140-3p/PDZK1 network in cervical cancer

Interventional effect of hesperetin on N-methyl-N'-nitro-N-nitrosoguanidine-induced exosomal circ008274 in affecting normal cells to promote gastric carcinogenesis

BACKGROUND

Hesperetin, a flavonoid predominantly present in citrus fruits, exhibits significant intervention effects on both the initiation and progression of gastric cancer. However, the specific mechanisms underlying this effect remain unclear.

AIM

To investigate the interventional role of hesperetin on N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced exosomes in inducing gastric carcinogenesis.

METHODS

Bioinformatics technology was used to identify the critical molecular components underlying hesperetin-mediated inhibition of MNNG induced gastric carcinogenesis through exosomal circular RNA. Biological experiments were conducted to validate these findings.

RESULTS

Exosomes derived from TGES-1 cells (TGES-1-EX) significantly enhanced the proliferation, migration, invasion, epithelial-mesenchymal transition (EMT), and stemness of GES-1 cells. The oncogenic potential of TGES-1-EX was significantly diminished following hesperetin pretreatment. TGES-1-EX with overexpressed or knocked down circ0008274 was extracted and GES-1 cells were treated in combination with hesperetin or alone. Our investigation revealed that hesperetin exerted significant inhibitory effects on MNNG-induced gastric carcinogenesis by exosomal circ0008274. Bioinformatics prediction identified microRNA (miR)-526b-5p as a potential miRNA binding to circ0008274. Functional experiments demonstrated that hesperetin may mediate its intervention in MNNG-induced gastric cancer initiation by targeting miR-526b-5p through exosomal circ0008274. TGES-1-EX circ0008274 promoted the proliferation, EMT, and cancer stem cell-like characteristics in GES-1 cells through miR-526b-5p-mediated regulatory mechanisms.

CONCLUSION

Hesperetin exerted an interventional effect on the gastric carcinogenesis process, particularly through the modulation of exosomal circ0008274 and its interaction with miR-526b-5p.

Circular RNA pappalysin-1 enhances glycolysis via microRNA-656-3p targeting G-protein subunit gamma-5 to promote colon cancer progression

BACKGROUND AND OBJECTIVE

Colon Cancer (CC) is a common malignant tumor. The aim of this study was to investigate the role and regulatory mechanism of circular RNA pappalysin-1 (circ-PAPPA; hsa_circ_0088233) in CC.

METHODS

In cancer tissues from CC patients, circ-PAPPA expression was measured and its relationship with patients' clinical features was analyzed. Plasmid vectors or oligonucleotides interfering with the expression of circ-PAPPA, microRNA (miR)-656-3p or G-protein subunit Gamma-5 (GNG5) were transfected into CC cells. Cell viability was detected by MTT and colony formation assay; apoptosis was detected by flow cytometry; and cell migration and invasion were detected by wound healing assay and Transwell. Glycolytic capacity of CC cells was assessed by measuring glucose uptake and lactate production using commercial kits. The targeting relationship between miR-656-3p and circ-PAPPA or GNG5 was verified by bioinformatics website starBase and dual luciferase reporter gene assay assays.

RESULTS

Circ-PAPPA was upregulated in CC and was negatively correlated with benign pathological features and 5-year survival rates of CC patients. Circ-PAPPA silencing inhibited the growth and glycolysis of CC cells through upregulating miR-656-3p. GNG5, a target of miR-656-3p, could reverse the impacts of silencing circ-PAPPA on CC cells.

CONCLUSION

Circ-PAPPA may play an oncogenic role in CC by promoting cell growth and glycolysis through the miR-656-3p/GNG5 axis.

Identifying MiR-140-3p as a stable internal reference to normalize MicroRNA qRT-PCR levels of plasma small extracellular vesicles in lung cancer patients

Exploration of a stably expressed gene as a reference is critical for the accurate evaluation of miRNAs isolated from small extracellular vesicles (sEVs). In this study, we analyzed small RNA sequencing on plasma sEV miRNAs in the training dataset (n = 104) and found that miR-140-3p was the most stably expressed candidate reference for sEV miRNAs. We further demonstrated that miR-140-3p expressed most stably in the validation cohort (n = 46) when compared to two other reference miRNAs, miR-451a and miR-1228-3p, and the commonly-used miRNA reference U6. Finally, we compared the capability of miR-140-3p and U6 as the internal reference for sEV miRNA expression by evaluating key miRNAs expression in lung cancer patients and found that miR-140-3p was more suitable as a sEV miRNA reference gene. Taken together, our data indicated miR-140-3p as a stable internal reference miRNA of plasma sEVs to evaluate miRNA expression profiles in lung cancer patients.

PDZK1 is correlated with DCE-MRI perfusion parameters in high-grade glioma

OBJECTIVE

This study investigated the relationship between PDZK1 expression and Dynamic Contrast-Enhanced MRI (DCE-MRI) perfusion parameters in High-Grade Glioma (HGG).

METHODS

Preoperative DCE-MRI scanning was performed on 80 patients with HGG to obtain DCE perfusion transfer coefficient (Ktrans), vascular plasma volume fraction (vp), extracellular volume fraction (ve), and reverse transfer constant (kep). PDZK1 in HGG patients was detected, and its correlation with DCE-MRI perfusion parameters was assessed by the Pearson method. An analysis of Cox regression was performed to determine the risk factors affecting survival, while Kaplan-Meier and log-rank tests to evaluate PDZK1's prognostic significance, and ROC curve analysis to assess its diagnostic value.

RESULTS

PDZK1 was upregulated in HGG patients and predicted poor overall survival and progression-free survival. Moreover, PDZK1 expression distinguished grade III from grade IV HGG. PDZK1 expression was positively correlated with Ktrans 90, and ve_90, and negatively correlated with kep_max, and kep_90.

CONCLUSION

PDZK1 is upregulated in HGG, predicts poor survival, and differentiates tumor grading in HGG patients. PDZK1 expression is correlated with DCE-MRI perfusion parameters.

Mechanism and function of miR-140 in human cancers: A review and in silico study

MicroRNA-140 (miR-140) acts as a tumor suppressor and plays a vital role in cell biological functions such as cell proliferation, apoptosis, and DNA repair. The expression of this miRNA has been shown to be considerably decreased in cancer tissues and cell lines compared with normal adjacent tissues. Consequently, aberrant expression of some miR-140 target genes can lead to the initiation and progression of various human cancers, such as breast cancer, gastrointestinal cancers, lung cancer, and prostate cancer. The dysregulation of the miR-140 network also affects cell proliferation, invasion, metastasis, and apoptosis of cancer cells by affecting various signaling pathways. Besides, up-regulation of miR-140 could enhance the efficacy of chemotherapeutic agents in different cancer. We aimed to cover most aspects of miR-140 function in cancer development and address its importance in different stages of cancer progression.

MALAT1-miRNAs network regulate thymidylate synthase and affect 5FU-based chemotherapy

Background

The active metabolite of 5-Fluorouracil (5FU), used in the treatment of several types of cancer, acts by inhibiting the thymidylate synthase encoded by the TYMS gene, which catalyzes the rate-limiting step in DNA replication. The major failure of 5FU-based cancer therapy is the development of drug resistance. High levels of TYMS-encoded protein in cancerous tissues are predictive of poor response to 5FU treatment. Expression of TYMS is regulated by various mechanisms, including involving non-coding RNAs, both miRNAs and long non-coding RNAs (lncRNAs).

Aim

To delineate the miRNAs and lncRNAs network regulating the level of TYMS-encoded protein.

Main body

Several miRNAs targeting TYMS mRNA have been identified in colon cancers, the levels of which can be regulated to varying degrees by lncRNAs. Due to their regulation by the MALAT1 lncRNA, these miRNAs can be divided into three groups: (1) miR-197-3p, miR-203a-3p, miR-375-3p which are downregulated by MALAT1 as confirmed experimentally and the levels of these miRNAs are actually reduced in colon and gastric cancers; (2) miR-140-3p, miR-330-3p that could potentially interact with MALAT1, but not yet supported by experimental results; (3) miR-192-5p, miR-215-5p whose seed sequences do not recognize complementary response elements within MALAT1. Considering the putative MALAT1-miRNAs interaction network, attention is drawn to the potential positive feedback loop causing increased expression of MALAT1 in colon cancer and hepatocellular carcinoma, where YAP1 acts as a transcriptional co-factor which, by binding to the TCF4 transcription factor/ β-catenin complex, may increase the activation of the MALAT1 gene whereas the MALAT1 lncRNA can inhibit miR-375-3p which in turn targets YAP1 mRNA.

Conclusion

The network of non-coding RNAs may reduce the sensitivity of cancer cells to 5FU treatment by upregulating the level of thymidylate synthase.