Background: Thyroid cancer (TC) is a prevalent endocrine malignancy with a generally favorable prognosis. However, dedifferentiation of TC poses a significant challenge, resulting in poorer patient outcomes and necessitating urgent attention. Cullin 4B (CUL4B), a scaffold protein involved in proteolysis and epigenetic regulation, has been reported to play an oncogenic role in many human malignancies, though its involvement in TC remains unclear. Methods: The association between CUL4B expression and prognosis in TC patients was assessed using immunohistochemistry. RNA-seq was utilized to investigate the underlying molecular mechanisms, which were further validated through in vitro experiments. The target gene of CUL4B was identified, and the complete ubiquitination regulation process was described. The phenomenon of high expression of CUL4B in TC was explained by identifying that CUL4B-mediated regulation of the SWI/SNF complex. Results: Our findings revealed that CUL4B expression was positively correlated with tumor progression and poor prognosis in TC. Mechanistically, overexpression of CUL4B promoted the progression and dedifferentiation of TC in vivo models. Crucially, we discovered that CUL4B drives dedifferentiation by promoting the ubiquitination of ARID1A within SWI/SNF complex, leading to decreased expression of the differentiation marker paired box 8 (PAX8). This loss of PAX8 contributes to the dedifferentiation process, ultimately resulting in the formation of anaplastic thyroid carcinoma (ATC). Moreover, silencing CUL4B increased the sensitivity of TC cells to MAPK inhibitors. Conclusion: CUL4B was crucial in driving tumor advancement and inhibiting differentiation in TC by facilitating the ubiquitin-mediated degradation of ARID1A, underscoring its potential as a therapeutic target.

BackgroundDisulfidptosis, a recently identified mechanism of cell death characterized by intracellular sulfide accumulation, leading to cellular exhaustion. Our objective is to create a prognostic model using a cohort of disulfidptosis-related genes (DRGs) to assess their prognostic value in lung adenocarcinoma (LUAD). This research not only deepens our understanding of the molecular mechanisms underpinning LUAD but also offers promising avenues for new clinical treatment biomarkers and therapeutic targets.MethodsWe employed various methodologies to assess DRGs in LUAD. Gene expression in single cell RNA sequencing (scRNA-seq) data was assessed using the AUcell algorithm. In the TCGA [LUAD] dataset, disulfidptosis-related enrichment scores were calculated using ssGSEA, and core gene sets were identified through the Weighted Gene Co-expression Network Analysis (WGCNA) algorithm. Differential gene analysis was conducted using the limma package and intersected with core gene sets. Univariate Cox regression analysis revealed genes with significant effects on LUAD prognosis. A prognostic model was developed using LASSO and Cox regression, utilizing median model scores for stratifying patient risk. Kaplan-Meier curves assessed prognostic differences between risk groups. Comprehensive analyses were performed on the tumor microenvironment (TME) and mutational landscape across different risk groups. Immune response characteristics and functional enrichment patterns were further evaluated in these cohorts.ResultsOur study delved into disulfidptosis in LUAD through a series of analyses: scRNA-seq data processing, WGCNA analysis, construction of a prognostic model, evaluation of clinical features and risk, enrichment analysis, mutation landscape assessment, and examination of the tumor microenvironment. We identified core genes related to disulfidptosis and established a prognostic model to classify patients based on risk scores. Notable differences in TME characteristics, immune cell infiltration, mutation landscape, and biological pathway activities were observed between risk groups, shedding new light on LUAD clinical treatment and biomarker discovery. Cell experiments highlighted the significance of KCNK1 in LUAD cells, suggesting its potential as a therapeutic target.ConclusionA prognostic model centered on DRGs was effectively developed to predict prognosis of LUAD and immunotherapy response. Our initial investigations unveiled KCNK1’s oncogenic role in LUAD, identifying it as a potential therapeutic target.

Chemotherapy is an effective therapeutic modality; nevertheless, a significant proportion of patients diagnosed with lung adenocarcinoma (LUAD) demonstrate resistance to chemotherapy. Therefore, it is crucial to understand the potential regulatory mechanisms to develop novel treatment strategies. This study aims to understand how increased FAM83B expression impacts mitochondrial activity, cell apoptosis, and chemotherapy effectiveness in LUAD. Multiple assays, such as CCK8, wound healing, EdU, and transwell assays, were employed to confirm the augmented chemotherapy resistance, heightened cell proliferation, migration, and invasion caused by FAM83B overexpression in LUAD cells. Furthermore, MIMP, MTG, and ATP assays were utilized to quantify changes in mitochondrial metabolism. In vitro functional assays were performed to evaluate the influence of FAM83B overexpression on the malignant progression and resistance mechanisms to chemotherapy in LUAD. In the context of this study, it was determined that LUAD patients with increased FAM83B expression had shorter survival times, and tissue samples with FAM83B overexpression were more prone to metastasis compared to primary samples. As a result, FAM83B is identified as an adverse prognostic marker. The mechanistic analysis demonstrated that FAM83B impedes the translocation of calbindin 2 (CALB2) from the cytoplasm to the mitochondria, resulting in the inhibition of apoptosis and the promotion of mitochondrial activity. Consequently, this ultimately confers resistance to chemotherapy in LUAD. Furthermore, the administration of metformin, which blocks mitochondrial oxidative phosphorylation (OXPHOS), can restore sensitivity to drug resistance in LUAD. Taken together, these findings provide substantial evidence supporting the notion that FAM83B enhances chemotherapy resistance in LUAD through the upregulation of mitochondrial metabolism and the inhibition of apoptosis.

Abstract Objects The family with sequence similarity 83B (FAM83B) is one of the markers for poor prognosis in several carcinomas, but the expression and the mechanism resulted in malignant phenotype in lung adenocarcinoma (LUAD) remain to be elucidated. Methods Data of RNA-seq in LUAD were downloaded from the cancer genome atlas (TCGA) database for differential expression and survival analysis, and immunohistochemistry was employed to analyze the protein expression of FAM83B in 126 cases of primary LUAD. The LUAD cell lines were collected for the detection of the effects on migration and invasion. Then, western blot was performed to measure the expression of tissue inhibitor of metalloproteinase (TIMP)-1 and activation of PI3K/AKT/NF-κB pathway. Results FAM83B was overexpressed in multiple types of carcinomas; The differential expression analysis revealed that the level of FAM83B was higher in LUAD than that in para-carcinoma; The patients with overexpression of FAM83B were with shorter overall survival (OS), disease specific survival (DSS) and progress free interval (PFI); Enrichment analysis suggested it was related to the focal adhesion of LUAD. Immunohistochemistry analysis demonstrated that higher FAM83B expression was positively related to lymph node metastasis in primary. Scratch assay and Borden chamber assay showed that the overexpression of FAM83B promoted migration and invasion activity in vitro. Furthermore, high level of FAM83B accelerated the tumorigenesis in vivo. Western blot showed that TIMP-1 was upregulated in H1299/FAM83B OE cells accompanying by the activation of PI3K/AKT/NF-κB pathway. Conclusions FAM83B was a marker for poor prognosis of LUAD and it might promote the expression of TIMP-1 by activating PI3K/AKT/NF-κB pathway and then affect the ECM balance, which resulted in the migration and invasion of LUAD.

Additional file 4. Supplementary Table 1. The related genes of FAM83B resulted from the LinkedOmics database.

Stromal cell-derived factor 1 (SDF-1)/CXCR4 ligand-receptor axis is widely recommended as an attractive target for cancer therapy. Meanwhile, epithelial-mesenchymal transition (EMT) process is linked to disease pathophysiology. As one of inhibitors of apoptosis proteins, survivin is implicated in the onset and development of cancer. In the present study, we tried to determine the cause-effect associations between SDF-1/CXCR4 axis and survivin expression in glioblastoma U-251 cell line. Survivin activation and inhibition were induced with exogenous SDF-1 and survivin small interfering RNA (survivin siRNA), respectively. Western blot was used to detect relevant proteins in SDF-1/CXCR4 axis. Western blot analysis revealed that survivin expression in U-251 increased in a dose- and time-dependent manner in response to SDF-1 treatment. However, the interference with MEK/ERK and PI3K/AKT pathway prohibited SDF-1-induced survivin up-regulation. Importantly, survivin knockdown abrogated cell cycle progression and the expression of snail and N-cadherin, compared with non-transfectants. In conclusion, the present study shows that SDF-1 up-regulates survivin via MEK/ERK and PI3K/AKT pathway, leading to cell cycle progression and EMT occurrence dependent on survivin. The blockade of survivin will allow for the treatment of glioblastoma.

In recent decades, the chemokine receptor CXCR4 and its ligand CXCL12 have been extensively reported to be associated with tumorigenesis. In addition, Twist signaling induces the epithelial-mesenchymal transition (EMT) process in glioblastoma development. In the present study, in vitro assays were used to investigate the role of CXCR4 and Twist in human glioblastoma. We explored the impact of CXCR4 and Twist on human glioblastoma using in vitro protein and gene assays. We found the administration of CXCL12 upregulated the expression of p-ERK, p-AKT, Twist, N-cadherin, and MMP9 in U87 cells, whereas the increase of E-cadherin protein was affected. Subsequently, Twist activity and EMT signaling were directly influenced by PD98059 and LY294002. Most importantly, the genetic silencing of Twist inhibited CXCL12-induced EMT occurrence, including proliferation, migration, and tumor formation of U87 cells. In conclusion, CXCL12/CXCR4 pathway activates ERK and PI3K/AKT signaling to upregulate Twist pathway, leading to the progression of EMT in human glioblastoma. Our study creates a new stage for molecule-targeted therapy of human glioblastoma.

In recent decades, the chemokine receptor CXCR4 and its ligand CXCL12 have been extensively reported to be associated with tumorigenesis. In addition, Twist signaling induces the epithelial-mesenchymal transition (EMT) process in glioblastoma development. In the present study, in vitro assays were used to investigate the role of CXCR4 and Twist in human glioblastoma. We explored the impact of CXCR4 and Twist on human glioblastoma using in vitro protein and gene assays. We found the administration of CXCL12 upregulated the expression of p-ERK, p-AKT, Twist, N-cadherin, and MMP9 in U87 cells, whereas the increase of E-cadherin protein was affected. Subsequently, Twist activity and EMT signaling were directly influenced by PD98059 and LY294002. Most importantly, the genetic silencing of Twist inhibited CXCL12-induced EMT occurrence, including proliferation, migration, and tumor formation of U87 cells. In conclusion, CXCL12/CXCR4 pathway activates ERK and PI3K/AKT signaling to upregulate Twist pathway, leading to the progression of EMT in human glioblastoma. Our study creates a new stage for molecule-targeted therapy of human glioblastoma.

Stromal cell-derived factor 1 (SDF-1)/CXCR4 ligand-receptor axis is widely recommended as an attractive target for cancer therapy. Meanwhile, epithelial-mesenchymal transition (EMT) process is linked to disease pathophysiology. As one of inhibitors of apoptosis proteins, survivin is implicated in the onset and development of cancer. In the present study, we tried to determine the cause-effect associations between SDF-1/CXCR4 axis and survivin expression in glioblastoma U-251 cell line. Survivin activation and inhibition were induced with exogenous SDF-1 and survivin small interfering RNA (survivin siRNA), respectively. Western blot was used to detect relevant proteins in SDF-1/CXCR4 axis. Western blot analysis revealed that survivin expression in U-251 increased in a dose- and time-dependent manner in response to SDF-1 treatment. However, the interference with MEK/ERK and PI3K/AKT pathway prohibited SDF-1-induced survivin up-regulation. Importantly, survivin knockdown abrogated cell cycle progression and the expression of snail and N-cadherin, compared with non-transfectants. In conclusion, the present study shows that SDF-1 up-regulates survivin via MEK/ERK and PI3K/AKT pathway, leading to cell cycle progression and EMT occurrence dependent on survivin. The blockade of survivin will allow for the treatment of glioblastoma.