POU4F1 confers trastuzumab resistance in HER2-positive breast cancer through regulating ERK1/2 signaling pathway

POU4F1 enhances lung cancer gemcitabine resistance by regulating METTL3-dependent TWF1 mRNA N6 adenosine methylation

This study aimed to investigate the role of POU Class 4 Homeobox 1 (POU4F1) in regulating gemcitabine (GEM) resistance in lung cancer cells. The mRNA and protein expressions were assessed using RT-qPCR, western blot, immunofluorescence, and immunohistochemistry. Cell viability and proliferation were assessed by CCK-8 assay and EdU assay. TUNEL staining and flow cytometry were employed to detect cell apoptosis. The m6A modification of TWF1 was detected using MeRIP assay. The interactions between molecules were validated using dual luciferase reporter gene, ChIP, and RIP assays. POU4F1 knockdown inhibited GEM resistance and autophagy in lung cancer cells. Mechanistically, POU4F1 transcriptionally activated methyltransferase-like protein 3 (METTL3) in GEM-resistant cells by binding to the METTL3 promoter. METTL3 promoted the N6-methyladenosine (m6A) modification and expression level of twinfilin-1 (TWF1). Overexpression of METTL3 and TWF1 weakened the effects of POU4F1 knockdown on GEM resistance and autophagy. Moreover, knockdown POU4F1 also enhanced GEM anti-tumor sensitivity in vivo. In conclusion, POU4F1 upregulation promoted GEM resistance in lung cancer cells by promoting autophagy through increasing METTL3-mediated TWF1 m6A modification.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-04161-w.

A novel liquid-liquid phase separation-related gene signature for predicting prognosis in colon cancer

Background

An increasing body of evidence indicates that dysregulation of liquid-liquid phase separation (LLPS) in cellular processes is implicated in the development of diverse tumors. Nevertheless, the association between LLPS and the prognosis, as well as the tumor immune microenvironment, in individuals with colon cancer remains poorly understood.

Methods

We conducted a comprehensive evaluation of the LLPS cluster in 1010 colon cancer samples from the TCGA and GEO databases, utilizing the expression profiles of LLPS-related prognostic differentially expressed genes (DEGs). Subsequently, a LLPS-related gene signature was constructed to calculate the LLPS-related risk score (LRRS) for each individual patient.

Results

Two LLPS subtypes were identified. Substantial variations were observed between the two LLPS subtypes in terms of prognosis, pathway activity, clinicopathological characteristics, and immune characteristics. Patients with high LRRS exhibited worse prognosis and poorer response to immunotherapy. LRRS was found to be correlated with the clinicopathological characteristics, genomic alterations, and the potential response to immune checkpoint inhibitors therapy of colon cancer patients. Additionally, the biological function of a key gene POU4F1 was verified in vitro.

Conclusions

This study highlights the crucial role of LLPS in colon cancer, LRRS can be used to predict the prognosis of colon cancer patients and aid in the identification of more effective immunotherapy strategies.

Identification of POU4F1 as a novel prognostic biomarker and therapeutic target in esophageal squamous cell carcinoma

BACKGROUND

Esophageal cancer is a significant global health concern, ranking seventh in incidence and sixth in mortality. It encompasses two pathological types: esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma, with ESCC being more prevalent globally and associated with higher mortality rates. The POU (Pit-Oct-Unc) domain family transcription factors, comprising 15 members, play important roles in embryonic development and organ formation. Aberrant expression of POUs has been observed in several human cancers, influencing cell proliferation, tumor invasion, and drug resistance. However, their specific role in ESCC remains unknown.

METHODS

We analyzed TCGA and GEO databases to assess POUs expression in ESCC tissues. Kaplan-Meier and ROC analyses were used to evaluate the prognostic value of POUs. Gene Set Enrichment Analysis and Protein-Protein interaction network were used to explore the potential pathway. Functional assays (Cell Counting Kit-8, EdU Staining assay, and cloning formation assay) and mechanism analyses (RNA-seq, flow cytometry, and Western blot) were conducted to determine the effects of POU4F1 knockdown on ESCC cell phenotypes and signaling pathways.

RESULTS

POU4F1 and POU6F2 were upregulated in various cancer tissues, including ESCC, compared to normal tissues. POU4F1 expression was significantly correlated with patient survival and superior to previous models (AUC = 0.776). Knockdown of POU4F1 inhibited ESCC cell proliferation and affected cell cycle, autophagy, and DNA damage pathways in ESCC cells.

CONCLUSION

POU4F1 is a novel and promising prognostic and therapeutic target for ESCC patients, providing insights into potential treatment strategies.

Identifying and evaluating a disulfidptosis-related gene signature to predict prognosis in colorectal adenocarcinoma patients

Disulfidptosis, a regulated form of cell death, has been recently reported in cancers characterized by high SLC7A11 expression, including invasive breast carcinoma, lung adenocarcinoma, and hepatocellular carcinoma. However, its role in colon adenocarcinoma (COAD) has been infrequently discussed. In this study, we developed and validated a prognostic model based on 20 disulfidptosis-related genes (DRGs) using LASSO and Cox regression analyses. The robustness and practicality of this model were assessed via a nomogram. Subsequent correlation and enrichment analysis revealed a relationship between the risk score, several critical cancer-related biological processes, immune cell infiltration, and the expression of oncogenes and cell senescence-related genes. POU4F1, a significant component of our model, might function as an oncogene due to its upregulation in COAD tumors and its positive correlation with oncogene expression. In vitro assays demonstrated that POU4F1 knockdown noticeably decreased cell proliferation and migration but increased cell senescence in COAD cells. We further investigated the regulatory role of the DRG in disulfidptosis by culturing cells in a glucose-deprived medium. In summary, our research revealed and confirmed a DRG-based risk prediction model for COAD patients and verified the role of POU4F1 in promoting cell proliferation, migration, and disulfidptosis.

FZKA reverses gefitinib resistance by regulating EZH2/Snail/EGFR signaling pathway in lung adenocarcinoma

ETHNOPHARMACOLOGICAL RELEVANCE

Fuzheng Kang-Ai (FZKA) decoction is mainly composed of 12 components with different types of herbs. In the last decade, FZKA has been used as an adjuvant treatment for lung cancer in clinical practice. Our previous studies have confirmed that FZKA shows a strong anti-cancer activity, significantly increases the clinical efficacy of gefitinib and reverses gefitinib resistance in non-small cell lung cancer (NSCLC). However, the molecular mechanism still needs to be further elucidated.

AIM OF THE STUDY

The aim of this study was to investigate the role and mechanism by which FZKA inhibited the cell growth, proliferation and invasion of lung adenocarcinoma(LUAD) and reversed the acquired resistance of gefitinib for the therapy in LUAD.

MATERIALS AND METHODS

Cell viability assay and EDU assay were used for detecting of cell viability and cell proliferation. Transwell assay was performed to measure cell invasion. Western Blot and qRT-PCR were used for protein and gene expression test. The gene promoter activity was determined by dul-luciferase reporter assay. The in situ expression of protein was measured by cell immunofluorescence. Stabilized cell lines were established for stable overexpression of EZH2. Transient transfection assay was used for gene silence and overexpression. Xenograft tumors and bioluminescent imaging were used for in vivo experiments.

RESULTS

FZKA significantly inhibited the cell viability, proliferation and cell invasion of LUAD, the combination of FZKA and gefitinib had a great synergy on the above processes. Moreover, FZKA significantly decreased EZH2 mRNA and protein expression, FZKA reversed the resistance of gefitinib by down-regulation of EZH2 protein. ERK1/2 kinase mediated the down-regulation of EZH2 reduced by FZKA. In addition, FZKA decreased the expression of Snail and EGFR by decreasing EZH2. Overexpression of Snail and EGFR significantly reversed the effect of FZKA-inhibited cell invasion and cell proliferation. More important, the combination of FZKA and gefitinib enhanced the inhibitory effect on EZH2, Snail and EGFR proteins. Furthermore, the growth inhibition and reversal of gefitinib resistance induced by FZKA were further validated in vivo. Finally, the expression and clinical correlation of EZH2,EGFR and Snail in cancer patients were further validated using bioinformatics analysis.

CONCLUSIONS

FZKA significantly suppressed tumor progression and reversed gefitinib resistance by regulating the p-ERK1/2-EZH2-Snail/EGFR signaling pathway in LUAD.

Xihuang pill facilitates glioma cell pyroptosis via the POU4F1/STAT3 axis

Glioma is the most common malignancy in the central nervous system. This study aims to disclose the impacts of Xihuang pill (XHP), a traditional Chinese formula, on glioma cell pyroptosis and relevant molecular mechanism. U251 and SHG-44 cells were treated with XHP alone or together with oe-POU4F1 and sh-STAT3. CCK8 assay detected the viability, flow cytometry evaluated pyroptosis, and microscopy observed cell morphology. LDH release was determined by the LDH kit and the levels of IL-1β and IL-18 were detected by ELISA. Immunofluorescence showed NLRP3 expression in glioma cells and western blotting measured the levels of POU4F1, STAT3, NLRP3, ASC, cleaved caspase-1, and IL-1β. The binding of POU4F1 to STAT3 was verified. Primary glioma model was established to observe tumor change by in vivo imaging, determine the levels of Ki67 and NLRP3 by immunochemistry, and detect relevant protein levels by western blotting. XHP treatment alone downregulated POU4F1 and STAT3 levels, aroused pyroptotic appearance in glioma cells such as ballooning swelling, reduced cell viability and number of pyroptotic cells, increased LDH release and IL-1β and IL-18 levels, formed NLRP3 sports in cells, and elevated the levels of pyroptosis-related proteins. However, POU4F1 overexpression or STAT3 silencing suppressed XHP-promoted pyroptosis. Mechanistically, POU4F1 acted as a transcription factor of STAT3 and regulated its transcription. In primary glioma models, XHP enhanced glioma cell pyroptosis and blocked glioma growth. XHP facilitates glioma cell pyroptosis via the POU4F1/STAT3 axis.

Development of an exosome-related and immune microenvironment prognostic signature in colon adenocarcinoma

Background: The correlation between exosomes and the tumor immune microenvironment has been proved to affect tumorigenesis and progression of colon adenocarcinoma (COAD). However, it remained unclear whether exosomes had an impact on the prognostic indications of COAD patients.

Methods: Expression of exosome-related genes (ERGs) and clinical data were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. The ERGs associated with prognosis were identified and exosome-related prognostic signature was constructed. Patients in two risk groups were classified according to the risk score calculation formula: Risk score = 1.0132 * CCKBR + 0.2416 * HOXC6 + 0.7618 * POU4F1. The expression of three ERGs was investigated by qRT-PCR. After that, we developed a nomogram predicting the likelihood of survival and verified its predictive efficiency. The differences of tumor immune microenvironment, immune cell infiltration, immune checkpoint and sensitivity to drugs in two risk groups were analyzed.

Results: A prognostic signature was established based on the three ERGs (CCKBR, HOXC6, and POU4F1) and patients with different risk group were distinguished. Survival analysis revealed the negative associated of risk score and prognosis, ROC curve analyses showed the accuracy of this signature. Three ERGs expression was investigated by qRT-PCR in three colorectal cancer cell lines. Moreover, risk score was positively correlated with tumor mutational burden (TMB), immune activities, microsatellite instability level, the expression of immune checkpoint genes. Meanwhile, the expression level of three ERGs and the risk score were markedly related with the sensitive response to chemotherapy.

Conclusion: The novel signature composed of three ERGs with precise predictive capabilities can be used to predict prognosis and provide a promising therapeutic target for improving the efficacy of immunotherapy.

The POU2F1-ALDOA axis promotes the proliferation and chemoresistance of colon cancer cells by enhancing glycolysis and the pentose phosphate pathway activity

Cancer metabolic reprogramming enhances its malignant behaviors and drug resistance, which is regulated by POU domain transcription factors. This study explored the effect of POU domain class 2 transcription factor 1 (POU2F1) on metabolic reprogramming in colon cancer. The POU2F1 expression was analyzed in GEO dataset, TCGA cohorts and human colon cancer tissues by bioinformatics and immunohistochemistry. The effects of altered POU2F1 expression on proliferation, glucose metabolism and oxaliplatin sensitivity of colon cancer cells were tested. The impacts of POU2F1 on aldolase A (ALDOA) expression and malignant behaviors of colon cancer cells were examined. We found that up-regulated POU2F1 expression was associated with worse prognosis and oxaliplatin resistance in colon cancer. POU2F1 enhanced the proliferation, aerobic glycolysis and the pentose phosphate pathway (PPP) activity, but reduced oxidative stress and apoptosis in colon cancer cells, dependent on up-regulating ALDOA expression. Mechanistically, POU2F1 directly bound to the ALDOA promoter to enhance the ALDOA promoter activity in colon cancer cells. Moreover, activation of the POU2F1-ALDOA axis decreased the sensitivity to oxaliplatin in colon cancer cells. These data indicate that the POU2F1-ALDOA axis promotes the progression and oxaliplatin resistance by enhancing metabolic reprogramming in colon cancer. Our findings suggest that the POU2F1-ALDOA axis may be new therapeutic targets to overcome oxaliplatin resistance in colon cancer.

HER2-ResNet: A HER2 classification method based on deep residual network

BACKGROUND:

HER2 gene expression is one of the main reference indicators for breast cancer detection and treatment, and it is also an important target for tumor targeted therapy drug selection. Therefore, the correct detection and evaluation of HER2 gene expression has important value for clinical treatment of breast cancer.

OBJECTIVE:

The study goal is to better classify HER2 images.

METHODS:

For general convolution neural network, with the increase of network layers, over fitting phenomenon is often very serious, which requires setting the value of random descent ratio, and parameter adjustment is often time-consuming and laborious, so this paper uses residual network, with the increase of network layer, the accuracy will not be reduced.

RESULTS:

In this paper, a HER2 image classification algorithm based on improved residual network is proposed. Experimental results show that the proposed HER2 network has high accuracy in breast cancer assessment.

Conclusion:

Taking HER2 images in Stanford University database as experimental data, the accuracy of HER2 image automatic classification is improved through experiments. This method will help to reduce the detection intensity and improve the accuracy of HER2 image classification.

Prognostic Biomarkers on a Competitive Endogenous RNA Network Reveals Overall Survival in Triple-Negative Breast Cancer

The objective of this study was to construct a competitive endogenous RNA (ceRNA) regulatory network using differentially expressed long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and mRNAs in patients with triple-negative breast cancer (TNBC) and to construct a prognostic model for predicting overall survival (OS) in patients with TNBC. Differentially expressed lncRNAs, miRNAs, and mRNAs in TNBC patients from the TCGA and Metabric databases were examined. A prognostic model based on prognostic scores (PSs) was established for predicting OS in TNBC patients, and the performance of the model was assessed by a recipient that operated on a distinctive curve. A total of 874 differentially expressed RNAs (DERs) were screened, among which 6 lncRNAs, 295 miRNAs and 573 mRNAs were utilized to construct targeted and coexpression ceRNA regulatory networks. Eight differentially expressed genes (DEGs) associated with survival prognosis, DBX2, MYH7, TARDBP, POU4F1, ABCB11, LHFPL5, TRHDE and TIMP4, were identified by multivariate Cox regression and then used to establish a prognostic model. Our study shows that the ceRNA network has a critical role in maintaining the aggressiveness of TNBC and provides comprehensive molecular-level insight for predicting individual mortality hazards for TNBC patients. Our data suggest that these prognostic mRNAs from the ceRNA network are promising therapeutic targets for clinical intervention.