The Tumor-Promoting Role of TRIP4 in Melanoma Progression and its Involvement in Response to BRAF-Targeted Therapy

Using machine learning methods to study the tumour microenvironment and its biomarkers in osteosarcoma metastasis

Background

The long-term prognosis for patients with osteosarcoma (OS) metastasis remains unfavourable, highlighting the urgent need for research that explores potential biomarkers using innovative methodologies.

Methods

This study explored potential biomarkers for OS metastasis by analysing data from the Cancer Genome Atlas Program (TCGA) and Gene Expression Omnibus (GEO) databases. The synthetic minority oversampling technique (SMOTE) was employed to tackle class imbalances, while genes were selected using four feature selection algorithms (Monte Carlo feature selection [MCFS], Borota, minimum-redundancy maximum-relevance [mRMR], and light gradient-boosting machine [LightGBM]) based on the gene expression matrix. Four machine learning (ML) algorithms (support vector machine [SVM], extreme gradient boosting [XGBoost], random forest [RF], and k-nearest neighbours [kNN]) were utilized to determine the optimal number of genes for building the model. Interpretable machine learning (IML) was applied to construct prediction networks, revealing potential relationships among the selected genes. Additionally, enrichment analysis, survival analysis, and immune infiltration were performed on the featured genes.

Results

In DS1, DS2, and DS3, the IML algorithm identified 53, 45, and 46 features, respectively. Using the merged gene set, we obtained a total of 79 interpretable prediction rules for OS metastasis. We subsequently conducted an in-depth investigation on 39 crucial molecules associated with predicting OS metastasis, elucidating their roles within the tumour microenvironment. Importantly, we found that certain genes act as both predictors and differentially expressed genes. Finally, our study unveiled statistically significant differences in survival between the high and low expression groups of TRIP4, S100A9, SELL and SLC11A1, and there was a certain correlation between these genes and 22 various immune cells.

Conclusions

The biomarkers discovered in this study hold significant implications for personalized therapies, potentially enhancing the clinical prognosis of patients with OS.

LINC00668 promoted non-small lung cancer progression by miR-518c-3p/TRIP4 axis

BACKGROUND

Non-small lung cancer ranks first in the cancer-related death of all malignant tumors. Exploring novel biological targets is of great significance for diagnosis and therapy of NSCLC.

OBJECTIVE

In this study, we aimed to explore the effect of LINC00668 on the biological functions of NSCLC cells and the underlying mechanism.

METHODS

RT-qPCR assays and western blot assays were utilized to estimate the relative gene expression at mRNA and protein levels, respectively. CCK8, colony formation, wound healing, transwell, and cell apoptosis assays were employed to assess cell function. IHC and FISH assays were used to determine the gene expression in NSCLC tissues. RIP and dual-luciferase assays were conducted to validate the combination between LINC00668 and miR-518c-3p. The correlation of expression between miR-518c-3p and LINC00668 or TRIP4 was determined by Pearson correlation analysis.

RESULTS

LINC00668 was aberrantly upregulated in NSCLC tumor tissues and cell lines. Inhibition of LINC00668 significantly suppressed tumor proliferation, migration, invasion and promoted cell apoptosis. Mechanistically, LINC00668 could bind to miR-518c-3p, thus targeting the 3'UTR of TRIP4. TRIP4 overexpression rescued the weakened cell function mediated by LINC00668 silencing.

CONCLUSIONS

LINC00668 acted as an oncogene in NSCLC progression through miR-518c-3p/TRIP4 axis. Our study disclosed a new mechanism of LINC00668 functioned in NSCLC and may give a deeper insight of the targeted therapy of NSCLC in the future.

TRIP4 transcriptionally activates DDIT4 and subsequent mTOR signaling to promote glioma progression

In spite of significant advances in the understanding of glioma biology and pathology, survival remains poor. Therefore, it is still of great significance to further explore the key factors involved in tumorigenesis and development in glioma and find potential new therapeutic targets. Here, we show that thyroid hormone receptor interactor 4 (TRIP4) is highly expressed in glioma cells and tissues. Patients of glioma with high expression of TRIP4 possess poor overall survival. Knockdown of TRIP4 inhibited tumor cell proliferation, metastasis, and apoptosis suppression, whereas overexpression of TRIP4 displays the opposite effects. Further research showed that TRIP4 promoted glioma progression through regulating DDIT4 expression and subsequent activation of mTOR signaling. DDIT4 overexpression restored the inhibition of tumor growth by TRIP4 knockdown in vitro and in vivo. Consistently, mTOR activity inhibition reversed TRIP4 overexpression-mediated tumor promotion in vitro and in vivo. Moreover, molecular mechanism exploration demonstrates that TRIP4 functions as a specific transcriptional activator to anchor at the promoter region of DDIT4 gene (-196 to -11) to regulate its transcription and such regulation was affected by HIF1α. Clinically, TRIP4 expression is positively correlated with DDIT4 expression in glioma samples based on tissue microarray analysis and both of their high expression predicts the malignancy of the disease. Altogether, our findings identify TRIP4 as a critical promoter of glioma progression by targeting DDIT4 and mTOR signaling successively and suggest that TRIP4-DDIT4 axis has potential to be a novel therapeutic target in glioma treatment.

Inherited Defects of the ASC-1 Complex in Congenital Neuromuscular Diseases

Defects in transcriptional and cell cycle regulation have emerged as novel pathophysiological mechanisms in congenital neuromuscular disease with the recent identification of mutations in the TRIP4 and ASCC1 genes, encoding, respectively, ASC-1 and ASCC1, two subunits of the ASC-1 (Activating Signal Cointegrator-1) complex. This complex is a poorly known transcriptional coregulator involved in transcriptional, post-transcriptional or translational activities. Inherited defects in components of the ASC-1 complex have been associated with several autosomal recessive phenotypes, including severe and mild forms of striated muscle disease (congenital myopathy with or without myocardial involvement), but also cases diagnosed of motor neuron disease (spinal muscular atrophy). Additionally, antenatal bone fractures were present in the reported patients with ASCC1 mutations. Functional studies revealed that the ASC-1 subunit is a novel regulator of cell cycle, proliferation and growth in muscle and non-muscular cells. In this review, we summarize and discuss the available data on the clinical and histopathological phenotypes associated with inherited defects of the ASC-1 complex proteins, the known genotype–phenotype correlations, the ASC-1 pathophysiological role, the puzzling question of motoneuron versus primary muscle involvement and potential future research avenues, illustrating the study of rare monogenic disorders as an interesting model paradigm to understand major physiological processes.

β-Elemene enhances radiosensitivity in non-small-cell lung cancer by inhibiting epithelial-mesenchymal transition and cancer stem cell traits via Prx-1/NF-kB/iNOS signaling pathway

Radiation therapy is widely used to treat a variety of malignant tumors, including non-small-cell lung cancer (NSCLC). However, ionizing radiation (IR) paradoxically promotes radioresistance, metastasis and recurrence by inducing epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs). Here, we developed two NSCLC radioresistant (RR) cell lines (A549-RR and H1299-RR) and characterized their motility, cell cycle distribution, DNA damage, and CSC production using migration/invasion assays, flow cytometry, comet assays, and sphere formation, respectively. We also evaluated their tumorigenicity in vivo using a mouse xenograft model. We found that invasion and spheroid formation by A549-RR and H1299-RR cells were increased as compared to their parental cells. Furthermore, as compared to radiation alone, the combination of β-elemene administration with radiation increased the radiosensitivity of A549 cells and reduced expression of EMT/CSC markers while inhibiting the Prx-1/NF-kB /iNOS signaling pathway. Our findings suggest that NSCLC radioresistance is associated with EMT, enhanced CSC phenotypes, and activation of the Prx-1/NF-kB/iNOS signaling pathway. They also suggest that combining β-elemene with radiation may be an effective means of overcoming radioresistance in NSCLC.

LncRNA MAFG-AS1 Promotes the Progression of Bladder Cancer by Targeting the miR-143-3p/COX-2 Axis

<b><i>Background:</i></b> Long noncoding RNAs (lncRNAs) are potential biomarkers that are very important for the development of cancer. Studies show that lncRNAs are significantly correlated with the carcinogenesis and progression of bladder cancer (BLCA). In this research, we aimed at probing into the role of lncRNA MAFG-AS1 in the tumorigenesis of BLCA. <b><i>Methods:</i></b> RT-qPCR was employed to detect MAFG-AS1 expression in BLCA tissues and cells. MAFG-AS1 siRNA and overexpression plasmid were transfected into 5637 and T24 BLCA cell lines to inhibit or upregulate MAFG-AS1 expression, respectively, and then the regulatory functions of MAFG-AS1 on BLCA cell proliferation, migration, and invasion were assessed using cell counting kit-8 (CCK-8) assay, EdU method, and Transwell experiments, respectively. Dual-luciferase reporter assay and RNA immunoprecipitation were conducted to validate the targeting relationships between MAFG-AS1 and miR-143-3p, and miR-143-3p and COX-2. In addition, miR-143-3p was repressed in MAFG-AS1-silenced 5637 and T24 cell lines, and the function of MAFG-AS1/miR-143-3p axis in BLCA cells was further evaluated. The regulatory effects of MAFG-AS1 and miR-143-3p on the expression of COX-2 protein were detected by Western blot. <b><i>Results:</i></b> MAFG-AS1 was remarkably upregulated in BLCA patient tissues and cell lines, and its high expression was closely related to histological grade, tumor size, and lymph node metastasis. Silencing of MAFG-AS1 inhibited BLCA cell proliferation, metastasis, and invasion, while overexpression of MAFG-AS1 in BLCA cells had opposite biological effects. MAFG-AS1 was proved to target miR-143-3p to repress its expression. Moreover, it was confirmed that MAFG-AS1 and miR-143-3p could modulate COX-2 expression. <b><i>Conclusion:</i></b> The MAFG-AS1/miR-143-3p/COX-2 axis contributes to BLCA progression.

MicroRNA-518-3p suppresses cell proliferation, invasiveness, and migration in colorectal cancer via targeting TRIP4

MicroRNA (miR)-518-3p has been shown to function as a tumor suppressor. This study was conducted to investigate the effects of miR-518-3p in colorectal cancer (CRC). The miR-518-3p mimic, mimic negative control (NC), miR-518-3p inhibitor, inhibitor-NC, ShRNA-TRIP4, and ShRNA-NC vectors were transfected into SW480 cells using Lipofectamine 2000. Cell viability was detected using CCK-8. Colony formation, cell invasiveness, and cell migration were assessed by plate colony formation, Transwell assays, and wound healing assays, respectively. Relative mRNA and protein levels were detected using RT-qPCR and Western blot, respectively. The target gene thyroid hormone receptor interactor 4 (TRIP4) of miR-518-3p was identified and further verified using dual-luciferase reporter assay. Compared with normal tissues, levels of miR-518-3p were decreased and TRIP4 was significantly increased in the tissues from patients with CRC. Following transfection with a miR-518-3p mimic or ShRNA-TRIP4, cell viability decreased in a time-dependent manner, and colony formation rate, wound closure rate, and the number of invasive cells were much lower for the transfected cells than in the corresponding NC and control groups. miR-518-3p overexpression or silencing of TRIP4 significantly down-regulated the expression of MMP-2 and MMP-9. Knockdown of miR-518-3p had the opposite effects, and TRIP4 was identified as a target of miR-518-3p. The inhibitory effects of miR-518-3p on the progressions of CRC are associated with TRIP4.

COX-2 Signaling in the Tumor Microenvironment

Tumorigenesis is a multistep, complicated process, and many studies have been completed over the last few decades to elucidate this process. Increasingly, many studies have shifted focus toward the critical role of the tumor microenvironment (TME), which consists of cellular players, cell-cell communications, and extracellular matrix (ECM). In the TME, cyclooxygenase-2 (COX-2) has been found to be a key molecule mediating the microenvironment changes. COX-2 is an inducible form of the enzyme that converts arachidonic acid into the signal transduction molecules (thromboxanes and prostaglandins). COX-2 is frequently expressed in many types of cancers and has been closely linked to its occurrence, progression, and prognosis. For example, COX-2 has been shown to (1) regulate tumor cell growth, (2) promote tissue invasion and metastasis, (3) inhibit apoptosis, (4) suppress antitumor immunity, and (5) promote sustainable angiogenesis. In this chapter, we summarize recent advances of studies that have evaluated COX-2 signaling in TME.

TRIP4 promotes tumor growth and metastasis and regulates radiosensitivity of cervical cancer by activating MAPK, PI3K/AKT, and hTERT signaling

Thyroid hormone receptor interactor 4 (TRIP4), a subunit of the tetrameric nuclear activating signal co-integrator 1 (ASC-1) complex, exerts pro-tumorigenic effects. The role for TRIP4 in the regulation of cervical cancer growth and radiation resistance is presently unknown. In this study, TRIP4 was found to be highly expressed in cervical cancer cells and tumor tissues. Knockdown of TRIP4 significantly suppressed cervical cancer cell proliferation and epithelial-mesenchymal transition (EMT), accompanied by inactivation of PI3K/AKT and MAPK/ERK signaling. TRIP4 was also found to target hTERT signaling by regulating its binding to the hTERT promoter. Moreover, the knockdown of TRIP4 increased cell sensitivity to radiation, concomitant with downregulation of Rad51 and p-H2AX. We also demonstrated in an in vivo study that the knockdown of TRIP4 effectively suppressed cervical cancer growth and progression in a xenograft tumor model, and these effects were concomitant with the downregulation of p-AKT, p-ERK, p-MEK1/2, MMP-9 and hTERT expression. Immunohistochemical analysis of tumor tissue microarrays showed that TRIP4 overexpression predicted poor prognosis in patients with cervical cancer. Collectively, these results show that TRIP4 plays an essential role in cervical cancer growth and survival.

Cyclooxygenase-2 in cancer: A review

Cyclooxygenase-2 (COX-2) is frequently expressed in many types of cancers exerting a pleiotropic and multifaceted role in genesis or promotion of carcinogenesis and cancer cell resistance to chemo- and radiotherapy. COX-2 is released by cancer-associated fibroblasts (CAFs), macrophage type 2 (M2) cells, and cancer cells to the tumor microenvironment (TME). COX-2 induces cancer stem cell (CSC)-like activity, and promotes apoptotic resistance, proliferation, angiogenesis, inflammation, invasion, and metastasis of cancer cells. COX-2 mediated hypoxia within the TME along with its positive interactions with YAP1 and antiapoptotic mediators are all in favor of cancer cell resistance to chemotherapeutic drugs. COX-2 exerts most of the functions through its metabolite prostaglandin E2. In some and limited situations, COX-2 may act as an antitumor enzyme. Multiple signals are contributed to the functions of COX-2 on cancer cells or its regulation. Members of mitogen-activated protein kinase (MAPK) family, epidermal growth factor receptor (EGFR), and nuclear factor-κβ are main upstream modulators for COX-2 in cancer cells. COX-2 also has interactions with a number of hormones within the body. Inhibition of COX-2 provides a high possibility to exert therapeutic outcomes in cancer. Administration of COX-2 inhibitors in a preoperative setting could reduce the risk of metastasis in cancer patients. COX-2 inhibition also sensitizes cancer cells to treatments like radio- and chemotherapy. Chemotherapeutic agents adversely induce COX-2 activity. Therefore, choosing an appropriate chemotherapy drugs along with adjustment of the type and does for COX-2 inhibitors based on the type of cancer would be an effective adjuvant strategy for targeting cancer.