FOXP3 activated-LINC01232 accelerates the stemness of non-small cell lung carcinoma by activating TGF-β signaling pathway and recruiting IGF2BP2 to stabilize TGFBR1

m6A reader IGF2BP2 promotes M2 macrophage polarization and malignant biological behavior of bladder cancer by stabilizing NRP1 mRNA expression

BACKGROUND

Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) has been confirmed to play oncogenic role in many cancers. However, the role and mechanism of IGF2BP2 in bladder cancer (BCa) still deserves to be further revealed.

METHODS

The mRNA and protein levels of IGF2BP2 and neuronilin-1 (NRP1) were detected by real-time quantitative PCR (RT-qPCR) and western blot. Cell proliferation, apoptosis, migration and invasion were determined using colony formation assay, EdU assay, CCK8 assay, flow cytometry and transwell assay. Xenograft tumor model was conducted to evaluate the role of IGF2BP2 in vivo. THP-1-M0 macrophages were co-cultured with the condition medium (CM) of BCa cells to induce polarization. M2 macrophage polarization was assessed by detecting the mRNA levels of M2 macrophage markers using RT-qPCR and measuring the proportion of M2 macrophage markers using flow cytometry. Moreover, MeRIP and RIP assay were performed to assess m6A level and the interaction between IGF2BP2 and NRP1.

RESULTS

IGF2BP2 and NRP1 were upregulated in BCa tissues and cells. IGF2BP2 knockdown suppressed BCa cell growth and metastasis, as well as inhibited BCa tumor growth. After THP-1-M0 macrophages were co-cultured with the CM of BCa cells, the levels of M2 macrophage markers were markedly enhanced, while this effect was abolished by IGF2BP2 knockdown. IGF2BP2 level was positively correlated with NRP1 level, and it could increase NRP1 mRNA stability. NRP1 overexpression reversed the suppressive effect of IGF2BP2 knockdown on M2 macrophage polarization and BCa cell progression.

CONCLUSION

m6A-reader IGF2BP2 enhanced M2 macrophage polarization and BCa cell progression by promoting NRP1 mRNA stability.

RNA regulatory mechanisms controlling TGF-β signaling and EMT in cancer

Epithelial-mesenchymal transition (EMT) is a major contributor to metastatic progression and is prominently regulated by TGF-β signalling. Both EMT and TGF-β pathway components are tightly controlled by non-coding RNAs - including microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) - that collectively have major impacts on gene expression and resulting cellular states. While miRNAs are the best characterised regulators of EMT and TGF-β signaling and the miR-200-ZEB1/2 feedback loop plays a central role, important functions for lncRNAs and circRNAs are also now emerging. This review will summarise our current understanding of the roles of non-coding RNAs in EMT and TGF-β signaling with a focus on their functions in cancer progression.

Systematic analysis of IGF2BP family members in non-small-cell lung cancer

BACKGROUND

The insulin-like growth factor-2 mRNA-binding proteins 1, 2, and 3 (IGF2BP1, IGF2BP2, and IGF2BP3) are known to be involved in tumorigenesis, metastasis, prognosis, and cancer immunity in various human cancers, including non-small cell lung cancer (NSCLC). However, the literature on NSCLC largely omits the specific context of lung squamous cell carcinoma (LUSC), an oversight we aim to address.

METHODS

Our study evaluated the differential expression of IGF2BP family members in tumors and normal tissues. Meta-analyses were conducted to assess the prognostic value of IGF2BPs in lung adenocarcinoma (LUAD) and LUSC. Additionally, correlations between IGF2BPs and tumor immune cell infiltration, mutation characteristics, chemotherapy sensitivity, and tumor mutation burden (TMB) were investigated. GSEA was utilized to delineate biological processes and pathways associated with IGF2BPs.

RESULTS

IGF2BP2 and IGF2BP3 expression were found to be upregulated in LUSC patients. IGF2BP2 mRNA levels were correlated with cancer immunity in both LUSC and LUAD patients. A higher frequency of gene mutations was observed in different IGF2BP1/2/3 expression groups in LUAD compared to LUSC. Meta-analyses revealed a significant negative correlation between overall survival (OS) and IGF2BP2/3 expression in LUAD patients but not in LUSC patients. GSEA indicated a positive association between VEGF and IGF2BP family genes in LUAD, while matrix metallopeptidase activity was inversely correlated with IGF2BP family genes in LUSC. Several chemotherapy drugs showed significantly lower IC50 values in high IGF2BP expression groups in both LUAD and LUSC.

CONCLUSION

Our findings indicated that IGF2BPs play different roles in LUAD and LUSC. This divergence highlights the need for tailored therapeutic strategies and prognostic tools, cognizant of the unique molecular profiles of LUAD and LUSC.

NANOS1 restricts oral cancer cell motility and TGF-ß signaling

Oral squamous cell carcinoma (OSCC) is the most frequent type of cancer of the head and neck area accounting for approx. 377,000 new cancer cases every year. The epithelial-to-mesenchymal transition (EMT) program plays an important role in OSCC progression and metastasis therefore contributing to a poor prognosis in patients with advanced disease. Transforming growth factor beta (TGF-ß) is a powerful inducer of EMT thereby increasing cancer cell aggressiveness. Here, we aimed at identifying RNA-binding proteins (RBPs) that affect TGF-ß-induced EMT. To this end we treated oral cancer cells with TGF-ß and identified a total of 643 significantly deregulated protein-coding genes in response to TGF-ß. Of note, 19 genes encoded RBPs with NANOS1 being the most downregulated RBP. Subsequent cellular studies demonstrated a strong inhibitory effect of NANOS1 on migration and invasion of SAS oral cancer cells. Further mechanistic studies revealed an interaction of NANOS1 with the TGF-ß receptor 1 (TGFBR1) mRNA, leading to increased decay of this transcript and a reduced TGFBR1 protein expression, thereby preventing downstream TGF-ß/SMAD signaling. In summary, we identified NANOS1 as negative regulator of TGF-ß signaling in oral cancer cells.

PURPL Promotes M2 Macrophage Polarization in Lung Cancer by Regulating RBM4/xCT Signaling

Lung cancer is the most common malignancy worldwide. Long non-coding RNA (lncRNA) p53 upregulated regulator of P53 levels (PURPL) is abnormally in various cancers. However, the reports on its roles in lung cancer are limited. The purpose of present study is to investigate the potentials of lncRNA PURPL in lung cancer. PURPL and mRNA expression was determined using real-time reverse transcriptase-polymerase chain reaction (RT-qPCR). The location of PURPL was detected using RNA fluorescence in situ hybridization (FISH) assay. Protein expression was detected using western blot. Cellular functions were determined using flow cytometry. The interaction between PURPL and RNA-binding motif 4 (RBM4) was confirmed using RNA immunoprecipitation (RIP) assay. PURPL was overexpressed in lung cancer cells and patients. Overexpressed PURPL promoted M2 macrophage polarization and suppressed ferroptosis. Additionally, PURPL maintained the mRNA stability of cystine glutamate reverse transporter (xCT) via regulating RBM4. xCT knockdown antagonized the effects of overexpressed PURPL and inhibited M2 macrophage polarization via inducing macrophage ferroptosis. PURPL/RBM4/xCT axis promoted M2 macrophage polarization in lung cancer. Therefore, PURPL may be a potential target of lung cancer.

Comprehensive landscape and future perspective of long noncoding RNAs in non-small cell lung cancer: it takes a village

Long noncoding RNAs (lncRNAs) are a distinct subtype of RNA that lack protein-coding capacity but exert significant influence on various cellular processes. In non-small cell lung cancer (NSCLC), dysregulated lncRNAs act as either oncogenes or tumor suppressors, contributing to tumorigenesis and tumor progression. LncRNAs directly modulate gene expression, act as competitive endogenous RNAs by interacting with microRNAs or proteins, and associate with RNA binding proteins. Moreover, lncRNAs can reshape the tumor immune microenvironment and influence cellular metabolism, cancer cell stemness, and angiogenesis by engaging various signaling pathways. Notably, lncRNAs have shown great potential as diagnostic or prognostic biomarkers in liquid biopsies and therapeutic strategies for NSCLC. This comprehensive review elucidates the significant roles and diverse mechanisms of lncRNAs in NSCLC. Furthermore, we provide insights into the clinical relevance, current research progress, limitations, innovative research approaches, and future perspectives for targeting lncRNAs in NSCLC. By summarizing the existing knowledge and advancements, we aim to enhance the understanding of the pivotal roles played by lncRNAs in NSCLC and stimulate further research in this field. Ultimately, unraveling the complex network of lncRNA-mediated regulatory mechanisms in NSCLC could potentially lead to the development of novel diagnostic tools and therapeutic strategies.

Various LncRNA Mechanisms in Gene Regulation Involving miRNAs or RNA-Binding Proteins in Non-Small-Cell Lung Cancer: Main Signaling Pathways and Networks

Long non-coding RNAs (lncRNAs) are crucial players in the pathogenesis of non-small-cell lung cancer (NSCLC). A competing binding of lncRNAs and mRNAs with microRNAs (miRNAs) is one of the most common mechanisms of gene regulation by lncRNAs in NSCLC, which has been extensively researched in the last two decades. However, alternative mechanisms that do not depend on miRNAs have also been reported. Among them, the most intriguing mechanism is mediated by RNA-binding proteins (RBPs) such as IGF2BP1/2/3, YTHDF1, HuR, and FBL, which increase the stability of target mRNAs. IGF2BP2 and YTHDF1 may also be involved in m6A modification of lncRNAs or target mRNAs. Some lncRNAs, such as DLGAP1-AS2, MALAT1, MNX1-AS1, and SNHG12, are involved in several mechanisms depending on the target: lncRNA/miRNA/mRNA interactome and through RBP. The target protein sets selected here were then analyzed using the DAVID database to identify the pathways overrepresented by KEGG, Wikipathways, and the Reactome pathway. Using the STRING website, we assessed interactions between the target proteins and built networks. Our analysis revealed that the JAK-STAT and Hippo signaling pathways, cytokine pathways, the VEGFA-VEGFR2 pathway, mechanisms of cell cycle regulation, and neovascularization are the most relevant to the effect of lncRNA on NSCLC.

LINC01232 targeting miR-1250-3p/MSH2 axis attenuates mesangial cell proliferation and fibrosis in diabetic nephropathy

The significance of long non-coding RNA (ncRNAs) in the initiation and progression of diabetic nephropathy (DN) has attracted much interest. The purpose of this work was to ascertain the role of LINC01232 in cell models and animal models of DN. C57BL/6 J mice were administered with streptozotocin (STZ) to develop animal models of DN, and mouse glomerular mesangial cells (MCs) were exposed to high glucose (HG) to establish cell models of DN. Expression levels of LINC01232, miR-1250-3p and MSH2 were identified by quantitative real-time PCR (qPCR) or western blotting. Fibrosis-related proteins were quantified by western blotting. MC proliferative capacity was checked by EdU assay. DN progression and fibrosis level in animal models were assessed by hematoxylin and eosin (HE) and Masson staining. The potential binding sites between miR-1250-3p and LINC01232 or MSH2 were examined by dual-luciferase reporter assay. LINC01232 expression was heightened in kidney tissues of DN patients. Its overexpression in HG-treated MCs alleviated MC proliferation and fibrosis. Overexpression of LINC01232 alleviated the pathological state of glomerular hypertrophy, MC hyperplasia, basement membrane thickening, and fibrosis in the DN models. LINC01232 bound to miR-1250-3p and competed for miR-1250-3p binding sites with MSH2. LINC01232 overexpression decoyed miR-1250-3p to increase MSH2 expression, and MSH2 depletion restored LINC01232 overexpression-inhibited MC proliferation and fibrosis. LINC01232 alleviated the mesangial cell proliferation and fibrosis in the progression of DN by targeting miR-1250-3p/MSH2 pathway.

The lncRNA LETS1 promotes TGF-β-induced EMT and cancer cell migration by transcriptionally activating a TβR1-stabilizing mechanism

Transforming growth factor-β (TGF-β) signaling is a critical driver of epithelial-to-mesenchymal transition (EMT) and cancer progression. In SMAD-dependent TGF-β signaling, activation of the TGF-β receptor complex stimulates the phosphorylation of the intracellular receptor-associated SMADs (SMAD2 and SMAD3), which translocate to the nucleus to promote target gene expression. SMAD7 inhibits signaling through the pathway by promoting the polyubiquitination of the TGF-β type I receptor (TβRI). We identified an unannotated nuclear long noncoding RNA (lncRNA) that we designated LETS1 (lncRNA enforcing TGF-β signaling 1) that was not only increased but also perpetuated by TGF-β signaling. Loss of LETS1 attenuated TGF-β-induced EMT and migration in breast and lung cancer cells in vitro and extravasation of the cells in a zebrafish xenograft model. LETS1 potentiated TGF-β-SMAD signaling by stabilizing cell surface TβRI, thereby forming a positive feedback loop. Specifically, LETS1 inhibited TβRI polyubiquitination by binding to nuclear factor of activated T cells (NFAT5) and inducing the expression of the gene encoding the orphan nuclear receptor 4A1 (NR4A1), a component of a destruction complex for SMAD7. Overall, our findings characterize LETS1 as an EMT-promoting lncRNA that potentiates signaling through TGF-β receptor complexes.

LncRNA DGUOK-AS1 facilitates non-small cell lung cancer growth and metastasis through increasing TRPM7 stability via m6A modification

BACKGROUND

N6-methyladenosine (m6A) modification plays key roles in tumor progression. LncRNA deoxyguanosine kinase antisense RNA 1 (DGUOK-AS1) has been reported as a promoter in tumors, but its role and mechanism in non-small cell lung cancer (NSCLC) development remain uncertain.

METHODS

Cell proliferation, migration, invasion and angiogenesis were investigated via CCK-8, colony formation, transwell, and tube formation assays, respectively. The location of DGUOK-AS1 was detected via FISH assay. The interaction relationship among DGUOK-AS1, IGF2BP2 and TRPM7 was confirmed by RIP and MeRIP assays. The effects of DGUOK-AS1 on NSCLC growth and metastasis in vivo were investigated using xenograft and pulmonary metastatic models.

RESULTS

DGUOK-AS1 was upregulated in NSCLC. DGUOK-AS1 silencing inhibited NSCLC cell proliferation, migration, invasion and angiogenesis. DGUOK-AS1 was mostly expressed in cytoplasm, and positively regulated IGF2BP2. METTL3/IGF2BP2 axis could increase TRPM7 mRNA stability in m6A-dependent manner. TRPM7 overexpression reversed the inhibitive function of DGUOK-AS1 silencing on NSCLC development. DGUOK-AS1 knockdown suppressed NSCLC cell growth and metastasis in nude mice.

CONCLUSION

DGUOK-AS1 silencing restrains NSCLC cell growth and metastasis through decreasing TRPM7 stability via regulation of the METTL3/IGF2BP2-mediated m6A modification.

TGF-β signaling pathway: Therapeutic targeting and potential for anti-cancer immunity

Transforming growth factor-β (TGFβ) is a pleiotropic secretory cytokine exhibiting both cancer-inhibitory and promoting properties. It transmits its signals via Suppressor of Mother against Decapentaplegic (SMAD) and non-SMAD pathways and regulates cell proliferation, differentiation, invasion, migration, and apoptosis. In non-cancer and early-stage cancer cells, TGFβ signaling suppresses cancer progression via inducing apoptosis, cell cycle arrest, or anti-proliferation, and promoting cell differentiation. On the other hand, TGFβ may also act as an oncogene in advanced stages of tumors, wherein it develops immune-suppressive tumor microenvironments and induces the proliferation of cancer cells, invasion, angiogenesis, tumorigenesis, and metastasis. Higher TGFβ expression leads to the instigation and development of cancer. Therefore, suppressing TGFβ signals may present a potential treatment option for inhibiting tumorigenesis and metastasis. Different inhibitory molecules, including ligand traps, anti-sense oligo-nucleotides, small molecule receptor-kinase inhibitors, small molecule inhibitors, and vaccines, have been developed and clinically trialed for blocking the TGFβ signaling pathway. These molecules are not pro-oncogenic response-specific but block all signaling effects induced by TGFβ. Nonetheless, targeting the activation of TGFβ signaling with maximized specificity and minimized toxicity can enhance the efficacy of therapeutic approaches against this signaling pathway. The molecules that are used to target TGFβ are non-cytotoxic to cancer cells but designed to curtail the over-activation of invasion and metastasis driving TGFβ signaling in stromal and cancer cells. Here, we discussed the critical role of TGFβ in tumorigenesis, and metastasis, as well as the outcome and the promising achievement of TGFβ inhibitory molecules in the treatment of cancer.

Roles of TGF‑β signalling pathway‑related lncRNAs in cancer (Review)

Long non-coding RNAs (lncRNAs) are a class of RNAs that are >200 nucleotides in length that do not have the ability to be translated into protein but are associated with numerous diseases, including cancer. The involvement of lncRNAs in the signalling of certain signalling pathways can promote tumour progression; these pathways include the transforming growth factor (TGF)-β signalling pathway, which is related to tumour development. The expression of lncRNAs in various tumour tissues is specific, and their interaction with the TGF-β signalling pathway indicates that they may serve as new tumour markers and therapeutic targets. The present review summarized the role of TGF-β pathway-associated lncRNAs in regulating tumorigenesis in different types of cancer and their effects on the TGF-β signalling pathway.

Elevated THBS3 predicts poor overall survival for clear cell renal cell carcinoma and identifies LncRNA/RBP/THBS3 mRNA networks

This study was used to assess THBS3's overall survival (OS) prognostic values in clear cell renal cell carcinoma (ccRCC) as well as to determine the LncRNA/RNA binding protein (RBP)/THBS3 interactions. Clinical data and RNA sequencing data were gathered from the TCGA dataset. Significant pathways associated with THBS3 were identified by gene set enrichment analysis (GSEA). Cox regression analyses, both univariate and multivariate, were applied to assess factors with independent prognostic abilities. We also discussed THBS3's relationship to immunity. We discovered that THBS3 expression was increased in ccRCC samples, as well as shorter OS in the TCGA dataset (P<0.05). External verification results in GSE6344, ICGC, ArrayExpress, UALCAN datasets, and qRT-PCR remained consistent (all P<0.05). Cox regression analyses, both univariate and multivariate, identified THBS3 as a factor with independent prognostic ability (both P<0.001). THBS3 expression as well as several clinicopathological variables were included in the nomogram OS prognosis prediction method as well. GSEA identified four THBS3-related signal pathways and THBS3 was revealed to be significantly associated with MSI, TMB, neoantigen, and immunity (all P<0.05). We also identified several LncRNA/RBP/THBS3 mRNA networks as potentially THBS3-related mechanisms. For THBS3-related drug sensitivities, THBS3 was negatively associated with Actinomycin D, Cobimetinib, Eribulin mesilate, Geldanamycin analog, and Vinblastine, while it was positively related to Erlotinib drug sensitivity. In addition to being an independent prognostic factor for ccRCC, THBS3 had a close connection to immunity, with identifying LncRNA/RBPs/THBS3 mRNA networks. Verifications of our findings in vivo and in vitro should be done in the future.

The role of FOXP3 in non-small cell lung cancer and its therapeutic potentials

Although in the last few decades we have witnessed the rapid development of treatments for non-small cell lung cancer (NSCLC), it still remains the leading cause of cancer-related death. Increasing efforts have been devoted to exploring potential biomarkers and molecular targets for NSCLC. Foxp3, a transcription factor that was discovered as a master regulator of regulatory T cells (Tregs), has been found to express abnormally in tumoral cells including lung cancer cells. In recent years, increasing evidence have surfaced, revealing the carcinogenic effect of FOXP3 in lung cancer. In this review, we analyzed and summarized the function of FOXP3, its regulation and therapeutic potentials in NSCLC, with a hope to facilitate the development of novel treatments for NSCLC.

IGF2BP2-induced circRUNX1 facilitates the growth and metastasis of esophageal squamous cell carcinoma through miR-449b-5p/FOXP3 axis

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is one of the most common digestive malignancies with relatively high morbidity and mortality. Emerging evidence suggests circular RNAs (circRNAs) play critical roles in tumor cell malignancy. However, the biological function and clinical significance of many circRNAs in ESCC remain elusive.

METHODS

The expression level and clinical implication of circRUNX1 in ESCC tissues were evaluated using qRT-PCR. In vitro and in vivo functional studies were conducted to investigate the underlying biological effects of circRUNX1 on ESCC cell growth and metastasis. Moreover, bioinformatics analysis, RNA sequencing (RNA-seq), RNA immunoprecipitation (RIP) assays, dual-luciferase reporter assays, and rescue experiments were performed to explore the relationships between circRUNX1, miR-449b-5p, Forkhead box protein P3 (FOXP3), and insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2).

RESULTS

CircRUNX1 was found to be significantly up-regulated in ESCC tissues and associated with TNM stage and differentiation grade. Functionally, circRUNX1 promoted ESCC cell proliferation and metastasis in vitro and in vivo. CircRUNX1 enhanced FOXP3 expression by competitively sponging miR-449b-5p. Notably, both miR-449b-5p mimics and FOXP3 knockdown restored the effects of circRUNX1 overexpression on cell proliferation and metastasis. Furthermore, IGF2BP2 binding to circRUNX1 prevented its degradation.

CONCLUSIONS

IGF2BP2 mediated circRUNX1 functions as an oncogenic factor to facilitate ESCC progression through the miR-449b-5p/FOXP3 axis, implying that circRUNX1 has the potential to be a promising diagnostic marker and therapeutic target for ESCC patients.

Crosstalk among long non-coding RNA, tumor-associated macrophages and small extracellular vesicles in tumorigenesis and dissemination

Long noncoding RNAs (lncRNAs), which lack protein-coding ability, can regulate cancer cell growth, proliferation, invasion, and metastasis. Tumor-associated macrophages (TAMs) are key components of the tumor microenvironment that have a significant impact on cancer progression. Small extracellular vesicles (sEV) are crucial mediators of intercellular communications. Cancer cell and macrophage-derived sEV can carry lncRNAs that influence the onset and progression of cancer. Dysregulation of lncRNAs, TAMs, and sEV is widely observed in tumors which makes them valuable targets for cancer immunotherapy. In this review, we summarize current updates on the interactions among sEV, lncRNAs, and TAMs in tumors and provide new perspectives on cancer diagnosis and treatment.