hsa_circ_0023305 Enhances Laryngeal Squamous Cell Carcinoma Progression and Modulates TRPM7 via miR-218-5p Sponging

Role of TRP channels in carcinogenesis and metastasis: Pathophysiology and regulation by non-coding RNAs

In 2021, David Julius and Ardem Patapoutian received Nobel Prize in Physiology or Medicine for their ground-breaking discoveries in the functional characterization of receptors for temperature and touch. Transient receptor potential (TRP) channels have captivated tremendous appreciation as promising drug targets over the past few years because of central involvement in different cancers. Based on the insights gleaned from decades of high-quality research, basic and clinical scientists have unveiled how Transient receptor potential channels regulated cancer onset and progression. Pioneering studies have sparked renewed interest and researchers have started to scratch the surface of mechanistic role of these channels in wide variety of cancers. In this review we have attempted to provide a summary of most recent updates and advancements made in the biology of these channels in context of cancers. We have partitioned this review into different subsections on the basis of emerging evidence about characteristically distinct role of TRPV (TRPV1, TRPV5), TRPM (TRPM3, TRPM7) and TRPC in cancers. Regulation of TRP channels by non-coding RNAs is also a very exciting area of research which will be helpful in developing a sharper understanding of the multi-step aspects of cancers.

Anti-cancer agent piperlongumine is an inhibitor of transient receptor potential melastatin 7 channel in oral squamous cell carcinoma

OBJECTIVES

To elucidate the association between the anticancer activities of piperlongumine (PL) and its potential target, transient receptor potential melastatin 7 channel (TRPM7), in oral squamous cell carcinoma (OSCC).

METHODS

The expression levels and electrical characteristics of TRPM7 as well as cell viability in response to various PL treatments were investigated in the OSCC cell line Cal27.

RESULTS

PL treatment resulted in a concentration- and time-dependent reduction in TRPM7 mRNA and protein expression in Cal27 cells. Furthermore, PL treatment inhibited TRPM7-like rectifying currents in Cal27 cells; however, this inhibition was less effective than that of the TRPM7 antagonist waixenicin A. Rapid perfusion and washout experiments revealed an immediate inhibitory effect of PL on TRPM7-like currents. The antagonistic effect of PL occurred within 1 min and was not completely reversed following washout. Notably, the extracellular Ca2+ concentration still influenced PL-induced changes in the TRPM7-like current, indicating that PL can directly but gently antagonize the TRPM7 channel. Functional changes in TRPM7 correlated with the observed antiproliferative and cytotoxic effects of PL in Cal27 cells.

CONCLUSIONS

These findings suggest that PL exhibits potent inhibitory effects on TRPM7 and exerts its anti-cancer effects by downregulating TRPM7 expression and antagonizing channel currents.

Exploring the evolving roles and clinical significance of circRNAs in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) represents the predominant malignancies in the head and neck region, and has limited therapeutic alternatives. Circular RNAs (circRNAs), a substantial category of non-coding RNA molecules, exert influential roles in human disease development and progression, employing various mechanisms such as microRNA sponging, interaction with RNA-binding proteins, and translational capabilities. Accumulating evidence highlights the differential expression of numerous circRNAs in HNSCC, and numerous dysregulated circRNAs underscore their crucial involvement in malignant advancement and resistance to treatment. This review aims to comprehensively outline the characteristics, biogenesis, and mechanisms of circRNAs, elucidating their functional significance in HNSCC. In addition, we delve into the clinical implications of circRNAs, considering their potential as biomarkers or targets for diagnosis, prognosis, and therapeutic applications in HNSCC. The discussion extends to exploring future challenges in the clinical translation of circRNAs, emphasizing the need for further research.

The Role of TRPM7 in Oncogenesis

This review summarizes the current understanding of the role of transient receptor potential melastatin-subfamily member 7 (TRPM7) channels in the pathophysiology of neoplastic diseases. The TRPM family represents the largest and most diverse group in the TRP superfamily. Its subtypes are expressed in virtually all human organs playing a central role in (patho)physiological events. The TRPM7 protein (along with TRPM2 and TRPM6) is unique in that it has kinase activity in addition to the channel function. Numerous studies demonstrate the role of TRPM7 chanzyme in tumorigenesis and in other tumor hallmarks such as proliferation, migration, invasion and metastasis. Here we provide an up-to-date overview about the possible role of TRMP7 in a broad range of malignancies such as tumors of the nervous system, head and neck cancers, malignant neoplasms of the upper gastrointestinal tract, colorectal carcinoma, lung cancer, neoplasms of the urinary system, breast cancer, malignant tumors of the female reproductive organs, prostate cancer and other neoplastic pathologies. Experimental data show that the increased expression and/or function of TRPM7 are observed in most malignant tumor types. Thus, TRPM7 chanzyme may be a promising target in tumor therapy.

Hsa_circ_0013561 promotes progression of nasopharyngeal carcinoma by activating JAK2/STAT3 signaling pathway

OBJECTIVE

Nasopharyngeal Carcinoma (NPC) is a malignancy of epithelium of epithelium of the nasopharynx, with the highest incidence of otolaryngeal malignancies. A growing number of studies confirm that Circular RNA (circRNA) plays an important role in tumor development, including Hsa_circ_0013561. This study aims to elucidate the process and mechanism of NPC regulation hsa_circ_0013561.

METHODS

In this study, circRNA expression nodes and subcellular localization in NPC tissues were analyzed by fluorescence in situ hybridization. The expression of hsa_circ_0013561 in NPC cells was further clarified by RT-qPCR. At the same time, the lentivirus vector interfered by hsa_circ_0013561 was constructed and transfected. The cell proliferation was detected by CCK-8 method, EdU assay and plate cloning assay. The cell cycle and apoptosis were detected by flow cytometry, and the cell migration ability was detected by wound healing assay and Transwell assay. Western blotting examined the expression of apoptosis, Epithelial-Mesenchymal Transition (EMT)-associated proteins, and Janus Kinase/Signal Transductor and Activator of Transcription (JAK/STAT) signaling pathway-related proteins.

RESULTS

The results showed that the expression of hsa_circ_0013561 in NPC samples was significantly upregulated and hsa_circ_0013561 localized in the cytoplasm. After down-regulating hsa_circ_0013561 expression, it significantly inhibited the proliferation and metastasis ability of NPC, inhibited EMT progression, and promoted apoptosis. Further studies showed that interference hsa_circ_0013561 significantly inhibited JAK2/STAT3 signaling pathway activation and induced the expression of apoptosis-related proteins.

CONCLUSION

In summary, we found that hsa_circ_0013561 is a pro-tumor circRNA in NPC, which can reduce the activation of JAK2/STAT3 pathway by knocking down hsa_circ_0013561, thereby slowing down the malignant progression of NPC. OXFORD CENTRE FOR EVIDENCE-BASED MEDICINE 2011 LEVELS OF EVIDENCE: Level 4.

Circular RNA circSLC7A11 contributes to progression and stemness of laryngeal squamous cell carcinoma via sponging miR-877-5p from LASP1

Background

Laryngeal squamous cell carcinoma (LSCC) belongs to tumors of head and neck. Circular RNA circSLC7A11 functions as oncogenes in various tumors. However, the role of circSLC7A11 in LSCC remains largely unknown. Here, we aimed to clarify the circSLC7A11 function in LSCC.

Methods

Relevance between circSLC7A11 expressions and LSCC clinicopathological was checked using chi-square. Relevance between circSLC7A11 expressions and LSCC patients' survival time was validated using Kaplan-Meier analysis. CircSLC7A11 expressions in LSCC tissues and cells were determined using quantitative real-time PCR. CircSLC7A11 functions in LSCC were examined by Cell Counting Kit-8, EdU analysis, Western blot, flow cytometry, sphere formation assay, and Transwell analysis. Meanwhile, circSLC7A11 mechanism in LSCC was determined using dual-luciferase reporter analysis, RNA pull-down, RNA Immunoprecipitation.

Results

CircSLC7A11 was highly expressed in LSCC, and high circSLC7A11 expressions were interrelated to the TNM stage. Also, LSCC patients with high circSLC7A11 owned shorter overall survival. Functional studies revealed that circSLC7A11 knockdown reduced LSCC cell proliferation, migration, invasion, stemness characteristics, and enhanced cell apoptosis. Mechanistic study data corroborated that circSLC7A11 targeted miR-877-5p, miR-877-5p targeted LASP1. LASP1 was negatively interrelated to miR-877-5p and was positively interrelated to circSLC7A11 in LSCC tissues. Also, circSLC7A11 knockdown reduced the LASP1 levels, and miR-877-5p inhibitor co-transfection reversed this reduction. Rescue assays further demonstrated that circSLC7A11 accelerated LSCC through miR-877-5p/LASP1.

Conclusion

CircSLC7A11 exerted oncogenic functions in LSCC by miR-877-5p/LASP1, hinting that circSLC7A11 was a novel biomarker for LSCC.

Biological and therapeutic viewpoints towards role of miR-218 in human cancers: Revisiting molecular interactions and future clinical translations

Understanding the exact pathogenesis of cancer is difficult due to heterogenous nature of tumor cells and multiple factors that cause its initiation and development. Treatment of cancer is mainly based on surgical resection, chemotherapy, radiotherapy and their combination, while gene therapy has been emerged as a new kind of therapy for cancer. Post-transcriptional regulation of genes has been of interest in recent years and among various types of epigenetic factors that can modulate gene expression, short non-coding RNAs known as microRNAs (miRNAs) have obtained much attention. The stability of mRNA decreases by miRNAs to repress gene expression. miRNAs can regulate tumor malignancy and biological behavior of cancer cells and understanding their function in tumorigenesis can pave the way towards developing new therapeutics in future. One of the new emerging miRNAs in cancer therapy is miR-218 that increasing evidence highlights its anti-cancer activity, while a few studies demonstrate its oncogenic function. The miR-218 transfection is promising in reducing progression of tumor cells. miR-218 shows interactions with molecular mechanisms including apoptosis, autophagy, glycolysis and EMT, and the interaction is different. miR-218 induces apoptosis, while it suppresses glycolysis, cytoprotective autophagy and EMT. Low expression of miR-218 can result in development of chemoresistance and radio-resistance in tumor cells and direct targeting of miR-218 as a key player is promising in cancer therapy. LncRNAs and circRNAs are nonprotein coding transcripts that can regulate miR-218 expression in human cancers. Moreover, low expression level of miR-218 can be observed in human cancers such as brain, gastrointestinal and urological cancers that mediate poor prognosis and low survival rate.