LIMD2 targeted by miR‑34a promotes the proliferation and invasion of non‑small cell lung cancer cells

Analysis of cuproptosis-related genes in Ulcerative colitis and immunological characterization based on machine learning

Cuproptosis is a novel form of cell death, mediated by protein lipid acylation and highly associated with mitochondrial metabolism, which is regulated in the cell. Ulcerative colitis (UC) is a chronic inflammatory bowel disease that recurs frequently, and its incidence is increasing worldwide every year. Currently, a growing number of studies have shown that cuproptosis-related genes (CRGs) play a crucial role in the development and progression of a variety of tumors. However, the regulatory role of CRGs in UC has not been fully elucidated. Firstly, we identified differentially expressed genes in UC, Likewise, CRGs expression profiles and immunological profiles were evaluated. Using 75 UC samples, we typed UC based on the expression profiles of CRGs, followed by correlative immune cell infiltration analysis. Using the weighted gene co-expression network analysis (WGCNA) methodology, the cluster's differentially expressed genes (DEGs) were produced. Then, the performances of extreme gradient boosting models (XGB), support vector machine models (SVM), random forest models (RF), and generalized linear models (GLM) were constructed and predicted. Finally, the effectiveness of the best machine learning model was evaluated using five external datasets, receiver operating characteristic curve (ROC), the area under the curve of ROC (AUC), a calibration curve, a nomogram, and a decision curve analysis (DCA). A total of 13 CRGs were identified as significantly different in UC and control samples. Two subtypes were identified in UC based on CRGs expression profiles. Immune cell infiltration analysis of subtypes showed significant differences between immune cells of different subtypes. WGCNA results showed a total of 8 modules with significant differences between subtypes, with the turquoise module being the most specific. The machine learning results showed satisfactory performance of the XGB model (AUC = 0.981). Finally, the construction of the final 5-gene-based XGB model, validated by the calibration curve, nomogram, decision curve analysis, and five external datasets (GSE11223: AUC = 0.987; GSE38713: AUC = 0.815; GSE53306: AUC = 0.946; GSE94648: AUC = 0.809; GSE87466: AUC = 0.981), also proved to predict subtypes of UC with accuracy. Our research presents a trustworthy model that can predict the likelihood of developing UC and methodically outlines the complex relationship between CRGs and UC.

Low-Dose Apatinib Improves the Prognosis of Patients with Recurrent High-Grade Gliomas

Objective. To evaluate the efficacy, safety, and prognostic value of low-dose apatinib in combination with temozolomide in the treatment of primary or recurrent high-grade gliomas (HGGs). Methods. A retrospective analysis of patients with postoperative and recurrent HGGs treated in our hospital from April 1, 2018, to April 30, 2020. Patients should be treated by combination therapy (surgery + radiotherapy + chemotherapy). Patients who received apatinib combined with temozolomide chemotherapy were allocated to the research group (RG), while patients who received temozolomide chemotherapy alone were allocated to the control group (CG). The efficacy and toxic side effects were compared between the two groups. Results. There were 67 qualified patients retrieved, including 37 cases in the RG and 30 cases in the CG. There were no significant differences in objective remission rate (ORR) or disease control rate (DCR) between the control group and the study group ( $P>0.05$ ). However, the overall improvement of clinical efficacy in the observation group was better than that in the control group ( $P<0.05$ ). There was no significant difference in the incidence of adverse effects between the two groups ( $P>0.05$ ). There were no significant differences in overall survival (OS) or progression-free survival (PFS) between the two groups ( $P>0.05$ ). Conclusion. Low-dose apatinib combined with temozolomide and radiotherapy for HGGs is effective in improving efficacy, relieving brain edema, reducing the use of glucocorticoid drugs, and improving patients’ quality of life. It has mild adverse effects and is well tolerated by patients.

LIM domain-containing 2 (LIMD2) promotes the progress of ovarian cancer via the focal adhesion signaling pathway

Ovarian cancer (OC) is the leading cause of death from gynecological cancer. In this study, we aimed to explore the role and potential mechanism of LIMD2 during the progression of OC. The expression of LIMD2 was analyzed by GEPIA (Gene Expression Profiling Interactive Analysis) database. Western blot and real-time PCR were applied to detect the gene expression of LIMD2 in OC cell lines. Cell counting kit-8 (CCK-8) assay, transwell, wound healing assays, and tumor xenograft experiments were used to evaluate the function of LIMD2 in vitro and vivo. Further, the LIMD2-associated pathways in OC were predicted by RNA-seq analysis, and the involvement of the corresponding cell signaling activities were confirmed by Western blot. We found that LIMD2 was high expressed in OC. Additionally, we found that silencing of LIMD2 inhibited OC cell proliferation in vitro and reduced the growth of its xenograft tumors. Moreover, knockdown of LIMD2 significantly decreased the migration of OC cells. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that pathways regulating extracellular matrix (ECM)-receptor interactions and focal adhesion signaling, were deregulated by LIMD2. Particularly, we confirmed that reducing LIMD2 could decrease the expression of Focal adhesion kinase (FAK) pathway related molecules. In conclusion, LIMD2 promotes the proliferation and invasion of ovarian cancer in vitro and in vivo, potentially through regulating the focal adhesion signaling pathway.

MEIS2 Is an Adrenergic Core Regulatory Transcription Factor Involved in Early Initiation of TH-MYCN-Driven Neuroblastoma Formation

Simple Summary

Neuroblastoma is a pediatric tumor originating from the sympathetic nervous system responsible for 10–15% of all childhood cancer deaths. Half of all neuroblastoma patients present with high-risk disease, of which nearly 50% relapse and die of their disease. In addition, standard therapies cause serious lifelong side effects and increased risk for secondary tumors. Further research is crucial to better understand the molecular basis of neuroblastomas and to identify novel druggable targets. Neuroblastoma tumorigenesis has to this end been modeled in both mice and zebrafish. Here, we present a detailed dissection of the gene expression patterns that underlie tumor formation in the murine TH-MYCN-driven neuroblastoma model. We identified key factors that are putatively important for neuroblastoma tumor initiation versus tumor progression, pinpointed crucial regulators of the observed expression patterns during neuroblastoma development and scrutinized which factors could be innovative and vulnerable nodes for therapeutic intervention.

Abstract

Roughly half of all high-risk neuroblastoma patients present with MYCN amplification. The molecular consequences of MYCN overexpression in this aggressive pediatric tumor have been studied for decades, but thus far, our understanding of the early initiating steps of MYCN-driven tumor formation is still enigmatic. We performed a detailed transcriptome landscaping during murine TH-MYCN-driven neuroblastoma tumor formation at different time points. The neuroblastoma dependency factor MEIS2, together with ASCL1, was identified as a candidate tumor-initiating factor and shown to be a novel core regulatory circuit member in adrenergic neuroblastomas. Of further interest, we found a KEOPS complex member (gm6890), implicated in homologous double-strand break repair and telomere maintenance, to be strongly upregulated during tumor formation, as well as the checkpoint adaptor Claspin (CLSPN) and three chromosome 17q loci CBX2, GJC1 and LIMD2. Finally, cross-species master regulator analysis identified FOXM1, together with additional hubs controlling transcriptome profiles of MYCN-driven neuroblastoma. In conclusion, time-resolved transcriptome analysis of early hyperplastic lesions and full-blown MYCN-driven neuroblastomas yielded novel components implicated in both tumor initiation and maintenance, providing putative novel drug targets for MYCN-driven neuroblastoma.

LIMD2 Regulates Key Steps of Metastasis Cascade in Papillary Thyroid Cancer Cells via MAPK Crosstalk

Although papillary thyroid carcinoma (PTC) has a good prognosis, 20–90% of patients show metastasis to regional lymph nodes and 10–15% of patients show metastasis to distant sites. Metastatic disease represents the main clinical challenge that impacts survival rate. We previously showed that LIMD2 was a novel metastasis-associated gene. In this study, to interrogate the role of LIMD2 in cancer invasion and metastasis, we used CRISPR-mediated knockout (KO) of LIMD2 in PTC cells (BCPAP and TPC1). Western blot and high-content screening (HCS) analysis confirmed functional KO of LIMD2. LIMD2 KO reduced in vitro invasion and migration. Ultrastructural analyses showed that cell polarity and mitochondria function and morphology were restored in LIMD2 KO cells. To unveil the signals supervising these phenotypic changes, we employed phospho-protein array. Several members of the MAPK superfamily showed robust reduction in phosphorylation. A Venn diagram displayed the overlap of kinases with reduced phosphorylation in both cell lines and showed that they were able to initiate or sustain the epithelial-mesenchymal transition (EMT) and DNA damage checkpoint. Flow cytometry and HCS validation analyses further corroborated the phospho-protein array data. Collectively, our findings show that LIMD2 enhances phosphorylation of kinases associated with EMT and invasion. Through cooperation with different kinases, it contributes to the increased genomic instability that ultimately promotes PTC progression.

An interactive network of alternative splicing events with prognostic value in geriatric lung adenocarcinoma via the regulation of splicing factors

Alternative splicing (AS), an essential process for the maturation of mRNAs, is involved in tumorigenesis and tumor progression, including angiogenesis, apoptosis, and metastasis. AS changes can be frequently observed in different tumors, especially in geriatric lung adenocarcinoma (GLAD). Previous studies have reported an association between AS events and tumorigenesis but have lacked a systematic analysis of its underlying mechanisms. In the present study, we obtained splicing event information from SpliceSeq and clinical information regarding GLAD from The Cancer Genome Atlas. Survival-associated AS events were selected to construct eight prognostic index (PI) models. We also constructed a correlation network between splicing factors (SFs) and survival-related AS events to identify a potential molecular mechanism involved in regulating AS-related events in GLAD. Our study findings confirm that AS has a strong prognostic value for GLAD and sheds light on the clinical significance of targeting SFs in the treatment of GLAD.

Knockdown of Thymidine Kinase 1 Suppresses Cell Proliferation, Invasion, Migration, and Epithelial-Mesenchymal Transition in Thyroid Carcinoma Cells

Patients with advanced thyroid carcinoma have poor prognosis with low overall survival. Unfortunately, the underlying mechanisms of thyroid carcinoma progression remain unclear. The elevated expression of thymidine kinase 1 (TK1) has been implicated in the progression of thyroid carcinoma, while the role of TK1 in thyroid carcinoma progression has not been explored. The present study aimed to determine the role TK1 in the progression of thyroid cancer and to explore the underlying molecular mechanisms. In this study, it was found that serum TK1 levels were markedly increased in the patients with thyroid nodules. Further online data mining showed that TK1 expression was upregulated in thyroid carcinoma tissues, and higher expression of TK1 was correlated with shorter disease-free survival of patients with thyroid carcinoma. Silencing of TK1 suppressed cell proliferation, invasion, migration, and epithelial–mesenchymal transition, and also induced cell apoptosis in the thyroid carcinoma cell lines. Animal studies showed that TK1 knockdown inhibited in vivo tumor growth of thyroid carcinoma cells. Importantly, miR-34a-5p was found to be downregulated in the thyroid carcinoma cells. Furthermore, miR-34a-5p targeted the 3′ untranslated region of TK1 and suppressed the expression of TK1 in thyroid carcinoma cell lines. In summary, first, these results demonstrated the upregulation of TK1 in thyroid nodules and thyroid carcinoma tissues; second, TK1 promoted thyroid carcinoma cell proliferation, invasion, and migration; lastly, TK1 was negatively regulated by miR-34a-5p. Our study may provide novel insights into the role of TK1 in regulating thyroid carcinoma progression.

Mechanism research of miR-34a regulates Axl in non-small-cell lung cancer with gefitinib-acquired resistance

Background

To investigate the regulatory mechanism behind miR‐34a‐altered Axl levels in non‐small‐cell lung cancer (NSCLC) with gefitinib‐acquired resistance.

Methods

The expression of miR‐34a, Axl, Gas6 and related downstream signaling proteins in the EGFR mutant NSCLC cell lines were determined by qRT‐PCR and Western blot; PC9‐Gef‐miR‐34a and HCC827‐Gef‐miR‐34a cells were established by transfecting the parent cells with a miR‐34a overexpressing virus, then the expression of Axl, Gas6 and the downstream channel‐related proteins were also compared in PC9‐Gef‐miR‐34a and HCC827‐Gef‐miR‐34a and drug‐resistant strains. The survival rate of the cells were measured by CCK8 assay. A luciferase reporter detected whether Axl was the target of miR‐34a. Finally, a tumor‐bearing nude mouse model was established to verify the relationship between the expression of miR‐34a, Axl and Gas6 mRNA in vivo.

Results

The expression levels of Axl mRNA and protein, Gas6 mRNA and protein, and related downstream proteins in PC9‐Gef and HCC827‐Gef cell lines were higher than those in PC9 and HCC827 parental cell lines, while the expression of miR‐34a was lower than it was in the parental cell lines (P < 0.05). The expression of Axl mRNA and protein, Gas6 mRNA and protein, and related downstream signaling proteins in PC9‐Gef and HCC827‐Gef cell lines was higher than the expression in PC9‐Gef‐miR‐34a and HCC827‐Gef‐miR‐34a cells, which overexpressed miR‐34a (P < 0.05).

Conclusion

The miR‐34a regulation of Axl plays an important role in NSCLC‐acquired gefitinib resistance, and their expression is inversely correlated, which suggests that they can be used as prognostic markers or potential therapeutic targets for NSCLC.