RB1CC1 functions as a tumor-suppressing gene in renal cell carcinoma via suppression of PYK2 activity and disruption of TAZ-mediated PDL1 transcription activation

Reduced Proline-Rich Tyrosine Kinase 2 Promotes Tumor Metastasis by Activating Epithelial-Mesenchymal Transition in Colorectal Cancer

BACKGROUND

Proline-rich tyrosine kinase 2 (PYK2) is involved in the occurrence, proliferation, migration, and invasion of various tumors. However, few studies have reported the role of PYK2 in colorectal cancer (CRC).

AIM

To explore the effects of PYK2 on CRC metastasis and elucidate the detailed molecular mechanisms involved.

METHODS

The expression and prognosis value of PYK2 in CRC prognosis were analyzed using data from The Cancer Genome Atlas (TCGA). PYK2 was knocked down or overexpressed in human CRC cell line, HCT116. Cell proliferation, migration, invasion, and cycle changes were analyzed using CCK-8, Transwell, and flow cytometry assays. Western blotting and quantitative real-time PCR were performed to detect the mRNA and protein levels of cell proliferation and epithelial-mesenchymal transition (EMT) indicators. Fluorescence staining was performed to examine the cytoskeleton.

RESULTS

Lower expression of PYK2 was observed in CRC tissues and associated with poor prognosis and metastasis in patients with CRC in TCGA database. PYK2 knockdown significantly induced the migration and invasion of CRC cells but did not affect cell proliferation or cycle. Immunofluorescence staining of phalloidin showed that the downregulation of PYK2 increased the cytoskeleton in CRC cells. Moreover, low expression of PYK2 induced the downregulation of E-cadherin and upregulation of snail and vimentin by activating Wnt/β-catenin signaling, thus promoting EMT in CRC cells.

CONCLUSIONS

Low PYK2 expression was found in tumor tissues, especially metastases, and significantly correlated with patient prognosis. Moreover, decreased PYK2 induces EMT by activating Wnt/β-catenin signaling, which is the potential mechanism of CRC metastasis. Regulating the expression of PYK2 to suppress tumor cell metastasis may represent a promising therapeutic strategy for metastatic CRC.

Emerging Role of Hippo-YAP (Yes-Associated Protein)/TAZ (Transcriptional Coactivator with PDZ-Binding Motif) Pathway Dysregulation in Renal Cell Carcinoma Progression

Although Hippo-YAP/TAZ pathway involvement has been extensively studied in the development of certain cancers, the involvement of this cascade in kidney cancer progression is not well-established and, therefore, will be the focus of this review. Renal cell carcinoma (RCC), the most prevalent kidney tumor subtype, has a poor prognosis and a high mortality rate. Core Hippo signaling inactivation (e.g., LATS kinases) leads to the nuclear translocation of YAP/TAZ where they bind to co-transcriptional factors such as TEAD promoting transcription of genes which initiates various fibrotic and neoplastic diseases. Loss of expression of LATS1/2 kinase and activation of YAP/TAZ correlates with poor survival in RCC patients. Renal-specific ablation of LATS1 in mice leads to the spontaneous development of several subtypes of RCC in a YAP/TAZ-dependent manner. Genetic and pharmacological inactivation of YAP/TAZ reverses the oncogenic potential in LATS1-deficient mice, highlighting the therapeutic benefit of network targeting in RCC. Here, we explore the unique upstream controls and downstream consequences of the Hippo-YAP/TAZ pathway deregulation in renal cancer. This review critically evaluates the current literature on the role of the Hippo pathway in RCC progression and highlights the recent scientific evidence designating YAP/TAZ as novel therapeutic targets against kidney cancer.

Frontier knowledge and future directions of programmed cell death in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is one of the most common renal malignancies of the urinary system. Patient outcomes are relatively poor due to the lack of early diagnostic markers and resistance to existing treatment options. Programmed cell death, also known as apoptosis, is a highly regulated and orchestrated form of cell death that occurs ubiquitously throughout various physiological processes. It plays a crucial role in maintaining homeostasis and the balance of cellular activities. The combination of immune checkpoint inhibitors plus targeted therapies is the first-line therapy to advanced RCC. Immune checkpoint inhibitors(ICIs) targeted CTLA-4 and PD-1 have been demonstrated to prompt tumor cell death by immunogenic cell death. Literatures on the rationale of VEGFR inhibitors and mTOR inhibitors to suppress RCC also implicate autophagic, apoptosis and ferroptosis. Accordingly, investigations of cell death modes have important implications for the improvement of existing treatment modalities and the proposal of new therapies for RCC. At present, the novel modes of cell death in renal cancer include ferroptosis, immunogenic cell death, apoptosis, pyroptosis, necroptosis, parthanatos, netotic cell death, cuproptosis, lysosomal-dependent cell death, autophagy-dependent cell death and mpt-driven necrosis, all of which belong to programmed cell death. In this review, we briefly describe the classification of cell death, and discuss the interactions and development between ccRCC and these novel forms of cell death, with a focus on ferroptosis, immunogenic cell death, and apoptosis, in an effort to present the theoretical underpinnings and research possibilities for the diagnosis and targeted treatment of ccRCC.

Linking Gene Fusions to Bone Marrow Failure and Malignant Transformation in Dyskeratosis Congenita

Dyskeratosis Congenita (DC) is a multisystem disorder intrinsically associated with telomere dysfunction, leading to bone marrow failure (BMF). Although the pathology of DC is largely driven by mutations in telomere-associated genes, the implications of gene fusions, which emerge due to telomere-induced genomic instability, remain unexplored. We meticulously analyzed gene fusions in RNA-Seq data from DC patients to provide deeper insights into DC's progression. The most significant DC-specific gene fusions were subsequently put through in silico assessments to ascertain biophysical and structural attributes, including charge patterning, inherent disorder, and propensity for self-association. Selected candidates were then analyzed using deep learning-powered structural predictions and molecular dynamics simulations to gauge their potential for forming higher-order oligomers. Our exploration revealed that genes participating in fusion events play crucial roles in upholding genomic stability, facilitating hematopoiesis, and suppressing tumors. Notably, our analysis spotlighted a particularly disordered polyampholyte fusion protein that exhibits robust higher-order oligomerization dynamics. To conclude, this research underscores the potential significance of several high-confidence gene fusions in the progression of BMF in DC, particularly through the dysregulation of genomic stability, hematopoiesis, and tumor suppression. Additionally, we propose that these fusion proteins might hold a detrimental role, specifically in inducing proteotoxicity-driven hematopoietic disruptions.

METTL14 inhibits malignant progression of oral squamous cell carcinoma by targeting the autophagy-related gene RB1CC1 in an m6A-IGF2BP2-dependent manner

N6-methyladenosine (m6A) plays crucial roles in tumorigenesis and autophagy. However, the underlying mechanisms mediated by m6A and autophagy in the malignant progression of oral squamous cell carcinoma (OSCC) remain unclear. In the present study, we revealed that down-regulated expression of METTL14 was correlated with advanced clinicopathological characteristics and poor prognosis in OSCC. METTL14 knockdown significantly inhibited autophagy and facilitated malignant progression in vitro, and promoted tumor growth and metastasis in vivo. A cell model of rapamycin-induced autophagy was established to identify RB1CC1 as a potential target gene involved in m6A-regulated autophagy in OSCC, through RNA sequencing and methylated RNA immunoprecipitation sequencing (meRIP-seq) analysis. Mechanistically, we confirmed that METTL14 posttranscriptionally enhanced RB1CC1 expression in an m6A-IGF2BP2-dependent manner, thereby affecting autophagy and progression in OSCC, through methylated RNA immunoprecipitation qRT-PCR (meRIP-qPCR), RNA stability assays, mutagenesis assays and dual-luciferase reporter. Collectively, our findings demonstrated that METTL14 serves as an OSCC suppressor by regulating the autophagy-related gene RB1CC1 through m6A modification, which may provide a new insight for the diagnosis and therapy of OSCC.

In silico analysis and experimental validation shows negative correlation between miR-1183 and cell cycle progression gene 1 expression in colorectal cancer

MicroRNAs (miRNAs) are small noncoding RNAs that post-transcriptionally regulate gene expression by binding to the 3' untranslated regions (UTR) of target genes. Aberrant expression of miRNAs can lead to disease, including cancer. Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. Among several factors, differential expression of miRNA can have serious consequences on disease progression. This study was designed to computationally identify and experimentally verify strong miRNA candidates that could influence CRC progression. In silico analysis of publicly available gene expression microarray datasets revealed significant upregulation of miR-1183 in CRC. Comparison of mRNA microarray expression data with predicted miR-1183 targets led to the identification of cell cycle progression gene 1 (CCPG1) as strong, negatively correlated miR-1183 target. Expression analysis by means of quantitative PCR validated the inverse correlation between miR-1183 and CCPG1 in colorectal cancer tissues. CCPG1 indirectly modulates the cell cycle by interacting with the PH/DH domain of Dbs (Rho-specific guanine nucleotide exchange factor). Interestingly, the computational analysis also showed that miR-1183 is upregulated in liver and gastric cancer. This finding is notable as the liver and stomach are the primary metastatic sites for colorectal cancer and hepatocellular carcinoma respectively. This novel finding highlights the broader implications of miR-1183 dysregulation beyond primary CRC, potentially serving as a valuable prognostic marker and a therapeutic target for both primary and metastatic CRC.

Activated PyK2 and Its Associated Molecules Transduce Cellular Signaling from the Cancerous Milieu for Cancer Metastasis

PyK2 is a member of the proline-rich tyrosine kinase and focal adhesion kinase families and is ubiquitously expressed. PyK2 is mainly activated by stimuli, such as activated Src kinases and intracellular acidic pH. The mechanism of PyK2 activation in cancer cells has been addressed extensively. The up-regulation of PyK2 through overexpression and enhanced phosphorylation is a key feature of tumorigenesis and cancer migration. In this review, we summarized the cancer milieu, including acidification and cancer-associated molecules, such as chemical reagents, interactive proteins, chemokine-related molecules, calcium channels/transporters, and oxidative molecules that affect the fate of PyK2. The inhibition of PyK2 leads to a beneficial strategy to attenuate cancer cell development, including metastasis. Thus, we highlighted the effect of PyK2 on various cancer cell types and the distribution of molecules that affect PyK2 activation. In particular, we underlined the relationship between PyK2 and cancer metastasis and its potential to treat cancer cells.

FMR1 is identified as an immune-related novel prognostic biomarker for renal clear cell carcinoma: A bioinformatics analysis of TAZ/YAP

WW domain-containing transcription regulator 1 (TAZ, or WWTR1) and Yes-associated protein 1 (YAP) are both important effectors of the Hippo pathway and exhibit different functions. However, few studies have explored their co-regulatory mechanisms in kidney renal clear cell carcinoma (KIRC). Here, we used bioinformatics approaches to evaluate the co-regulatory roles of TAZ/YAP and screen novel biomarkers in KIRC. GSE121689 and GSE146354 were downloaded from the GEO. The limma was applied to identify the differential expression genes (DEGs) and the Venn diagram was utilized to screen co-expressed DEGs. Co-expressed DEGs obtained the corresponding pathways through GO and KEGG analysis. The protein-protein interaction (PPI) network was constructed using STRING. The hub genes were selected applying MCODE and CytoHubba. GSEA was further applied to identify the hub gene-related signaling pathways. The expression, survival, receiver operating character (ROC), and immune infiltration of the hub genes were analyzed by HPA, UALCAN, GEPIA, pROC, and TIMER. A total of 51 DEGs were co-expressed in the two datasets. The KEGG results showed that the enriched pathways were concentrated in the TGF-β signaling pathway and endocytosis. In the PPI network, the hub genes (STAU2, AGO2, FMR1) were identified by the MCODE and CytoHubba. The GSEA results revealed that the hub genes were correlated with the signaling pathways of metabolism and immunomodulation. We found that STAU2 and FMR1 were weakly expressed in tumors and were negatively associated with the tumor stages. The overall survival (OS) and disease-free survival (DFS) rate of the high-expressed group of FMR1 was greater than that of the low-expressed group. The ROC result exhibited that FMR1 had certainly a predictive ability. The TIMER results indicated that FMR1 was positively correlated to immune cell infiltration. The abovementioned results indicated that TAZ/YAP was involved in the TGF-β signaling pathway and endocytosis. FMR1 possibly served as an immune-related novel prognostic gene in KIRC.

Circ-CUL2/microRNA-888-5p/RB1CC1 axis participates in cisplatin resistance in NSCLC via repressing cell advancement

Elevated evidences manifest that circular RNAs (circRNAs) are vital in human tumor advancement and chemotherapy resistance. The study was to explore the character of Circ-CUL2 in non-small cell lung cancer (NSCLC). Firstly, the expression of circ-CUL2, microRNA (miR)-888-5p and RB1CC1 was detected in human NSCLC tissues and cell lines by reverse transcription quantitative polymerase chain reaction or Western blot. Then, cell counting kit (CCK)-8, plate clone, Transwell assays, and flow cytometry were applied to separately detect the impacts of circ-CUL2 on proliferation, migration, invasion, apoptosis and cisplatin (DDP) resistance of A549/DDP cells. In this study, exploration of the biological function of Circ-CUL2 was via the Circ-CUL2/miR-888-5p/RB1CC1 axis. The results manifested circ-CUL2 and RB1CC1 were down-regulated in NSCLC tissues and cell lines, while miR-888-5p was up-regulated. Elevated Circ-CUL2 or refrained miR-888-5p repressed A549/DDP cell progression with depressive DDP resistance. Circ-CUL2 curbed miR-888-5p, which targeted RB1CC1. Restrained RB1CC1 turned around the impacts of Circ-CUL2 on the cells. All in all, Circ-CUL2 is anti-NSCLC via miR-888-5p/RB1CC1 axis, enhancing the sensitivity of A549/DDP cells to DDP. Hence, Circ-CUL2 is supposed to be a novel biomarker offering a brand-new strategy for NSCLC therapy.