ABSTRACT
Approximately 20% of colorectal cancer (CRC) patients are first diagnosed with metastatic colorectal cancer (mCRC) because they develop symptoms at an advanced stage. Despite advancements in treatment, patients with metastatic disease still experience inferior survival rates. Our objective is to investigate the association between long noncoding RNAs (lncRNAs) and prognosis and to explore their role in mCRC. In this study, we find that elevated expression of PCAT6 is independently linked to unfavourable survival outcomes in The Cancer Genome Atlas (TCGA) data, and this finding is further confirmed in CRC samples obtained from Fudan University Shanghai Cancer Center. Cell lines and xenograft mouse models are used to examine the impact of PCAT6 on tumor metastasis. Knockdown of PCAT6 is observed to impede the metastatic phenotype of CRC, as evidenced by functional assays, demonstrating the suppression of epithelial-mesenchymal transition (EMT) and stemness. Our findings show the significance of PCAT6 in mCRC and its potential use as a prognostic biomarker.
Subject(s)
Colorectal Neoplasms , Epithelial-Mesenchymal Transition , Neoplastic Stem Cells , RNA, Long Noncoding , Animals , Female , Humans , Male , Mice , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Cell Line, Tumor , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/mortality , Epithelial-Mesenchymal Transition/genetics , Gene Expression Regulation, Neoplastic , Mice, Nude , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Prognosis , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , RNA, Untranslated/geneticsABSTRACT
Currently, platinum-containing regimens are the most commonly used regimens for advanced gastric cancer patients, and chemotherapy resistance is one of the main reasons for treatment failure. Thus, it is important to reveal the mechanism of oxaliplatin resistance and to seek effective intervention strategies to improve chemotherapy sensitivity, thereby improving the survival and prognosis of gastric cancer patients. To understand the molecular mechanisms of oxaliplatin resistance, we generate an oxaliplatin-resistant gastric cancer cell line and conduct assay for transposase-accessible chromatin sequencing (ATAC-seq) and RNA sequencing (RNA-seq) for both parental and oxaliplatin-resistant AGS cells. A total of 3232 genomic regions are identified to have higher accessibility in oxaliplatin-resistant cells, and DNA-binding motif analysis identifies JUNB as the core transcription factor in the regulatory network. JUNB is overexpressed in oxaliplatin-resistant gastric cancer cells, and its upregulation is associated with poor prognosis in gastric cancer patients, which is validated by our tissue microarray data. Moreover, chromatin immunoprecipitation sequencing (ChIP-seq) analysis reveals that JUNB binds to the transcriptional start site of key genes involved in the MAPK signaling pathway. Knockdown of JUNB inhibits the MAPK signaling pathway and restores sensitivity to oxaliplatin. Combined treatment with the ERK inhibitor piperlongumine or MEK inhibitor trametinib effectively overcomes oxaliplatin resistance. This study provides evidence that JUNB mediates oxaliplatin resistance in gastric cancer by activating the MAPK pathway. The combination of MAPK inhibitors with oxaliplatin overcomes resistance to oxaliplatin, providing a promising treatment opportunity for oxaliplatin-resistant gastric cancer patients.
Subject(s)
Stomach Neoplasms , Humans , Oxaliplatin/pharmacology , Oxaliplatin/therapeutic use , Stomach Neoplasms/drug therapy , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Chromatin/genetics , Transcriptome , Signal TransductionABSTRACT
The emergence of anti-EGFR therapy has revolutionized the treatment of colorectal cancer (CRC). However, not all patients respond consistently well. Therefore, it is imperative to conduct further research to identify the molecular mechanisms underlying the development of cetuximab resistance in CRC. In this study, we find that the expressions of many metabolism-related genes are downregulated in cetuximab-resistant CRC cells compared to their sensitive counterparts. Specifically, acetyl-CoA acyltransferase 2 (ACAA2), a key enzyme in fatty acid metabolism, is downregulated during the development of cetuximab resistance. Silencing of ACAA2 promotes proliferation and increases cetuximab tolerance in CRC cells, while overexpression of ACAA2 exerts the opposite effect. RTK-Kras signaling might contribute to the downregulation of ACAA2 expression in CRC, and ACAA2 predicts CRC prognosis in patients with Kras mutations. Collectively, our data suggest that modulating ACAA2 expression contributes to secondary cetuximab resistance in Kras wild-type CRC patients. ACAA2 expression is related to Kras mutation and demonstrates a prognostic role in CRC patients with Kras mutation. Thus, ACAA2 is a potential target in CRC with Kras mutation.
Subject(s)
Antineoplastic Agents , Colorectal Neoplasms , Humans , Acetyl Coenzyme A/genetics , Acetyl Coenzyme A/metabolism , Acetyl Coenzyme A/pharmacology , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cetuximab/pharmacology , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Drug Resistance, Neoplasm/genetics , Mutation , Proto-Oncogene Proteins p21(ras)/genetics , Signal TransductionABSTRACT
BACKGROUND: The anti-epidermal growth factor receptor (EGFR) antibody introduces adaptable variations to the transcriptome and triggers tumor immune infiltration, resulting in colorectal cancer (CRC) treatment resistance. We intended to identify genes that play essential roles in cetuximab resistance and tumor immune cell infiltration. METHODS: A cetuximab-resistant CACO2 cellular model was established, and its transcriptome variations were detected by microarray. Meanwhile, public data from the Gene Expression Omnibus and The Cancer Genome Atlas (TCGA) database were downloaded. Integrated bioinformatics analysis was applied to detect differentially expressed genes (DEGs) between the cetuximab-resistant and the cetuximab-sensitive groups. Then, we investigated correlations between DEGs and immune cell infiltration. The DEGs from bioinformatics analysis were further validated in vitro and in clinical samples. RESULTS: We identified 732 upregulated and 1259 downregulated DEGs in the induced cellular model. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses, along with Gene Set Enrichment Analysis and Gene Set Variation Analysis, indicated the functions of the DEGs. Together with GSE59857 and GSE5841, 12 common DEGs (SATB-2, AKR1B10, ADH1A, ADH1C, MYB, ATP10B, CDX-2, FAR2, EPHB2, SLC26A3, ORP-1, VAV3) were identified and their predictive values of cetuximab treatment were validated in GSE56386. In online Genomics of Drug Sensitivity in Cancer (GDSC) database, nine of twelve DEGs were recognized in the protein-protein (PPI) network. Based on the transcriptome profiles of CRC samples in TCGA and using Tumor Immune Estimation Resource Version 2.0, we bioinformatically determined that SATB-2, ORP-1, MYB, and CDX-2 expressions were associated with intensive infiltration of B cell, CD4+ T cell, CD8+ T cell and macrophage, which was then validated the correlation in clinical samples by immunohistochemistry. We found that SATB-2, ORP-1, MYB, and CDX-2 were downregulated in vitro with cetuximab treatment. Clinically, patients with advanced CRC and high ORP-1 expression exhibited a longer progression-free survival time when they were treated with anti-EGFR therapy than those with low ORP-1 expression. CONCLUSIONS: SATB-2, ORP-1, MYB, and CDX-2 were related to cetuximab sensitivity as well as enhanced tumor immune cell infiltration in patients with CRC.
ABSTRACT
PURPOSE: Metabolic genes are associated with the occurrence and development of tumors. Metabolic-related risk models have showed partly prognostic predictive ability in cancers. However, the correlation between metabolic-related genes (MRGs) and the outcome of colorectal cancer is still poorly understood. PATIENTS AND METHODS: TCGA database is used as the training cohort; while GSE39582 is the verification cohort. The least absolute shrinkage and selection operator Cox regression analysis were utilized to identify the MRGs and establish a genetic risk scoring model. A nomogram by integrating MRGs risk scores with TNM stage was constructed. The potential biological mechanisms were explored using gene set enrichment analysis. Associations of the signature with immune cell infiltrations and the tumor mutation burden (TMB) were also uncovered by Spearman rank test. RESULTS: A six-gene metabolic signature was identified. Based on the risk scoring model with the signature, patients were divided into two groups (high-risk versus low-risk). The overall survival (OS) duration of patients with high-risk were quite shorter than those of low-risk patients (TCGA: p < .001, GSE39582: p < .001). Metabolic-related pathways were major enriched in low-risk group, while the high-risk group exhibited multiple immune-related pathways. Moreover, our signature was more linear dependent with antigen-presenting cell than effector immune cells, and a positive correction were seen between our signature and TMB. CONCLUSION: Our research has discovered a six-gene metabolic signature to predict the OS of colorectal cancer. These genes may play significant roles in colorectal cancer regulating tumor microenvironment and serving as potential biomarkers for anti-cancer therapy.
Subject(s)
Biomarkers, Tumor , Colorectal Neoplasms , Biomarkers, Tumor/genetics , Colorectal Neoplasms/genetics , Humans , Kaplan-Meier Estimate , Prognosis , Risk Factors , Tumor MicroenvironmentABSTRACT
MicroRNAs have been implicated in nerve injury and neuropathic pain. In the previous study we had shown that miR-96 can attenuate neuropathic pain through inhibition of Nav1.3. In this study, we investigated the role of miR-183, a same cluster member of microRNA with miR-96, in neuropathic pain and its potential mechanisms. We found that the expression level of miR-183-5p in dorsal root ganglion was decreased with the development of neuropathic pain induced by chronic constriction sciatic nerve injury (CCI). By contrast, the TREK-1, a K+ channel, was increased. Further investigation identified that intrathecal injection of miR-183-5p mimic efficiently ameliorated neuropathic pain and inhibited the expression of TREK-1, a predicted target gene of miR-183-5p. Luciferase assays confirmed the binding of miR-183-5p and TREK-1. In addition, over-expression of TREK-1 blocked the roles of miR-183-5p in neuropathic pain. Our findings suggested that miR-183-5P participated in the regulation of CCI-induced neuropathic pain through inhibiting the expression of TREK-1.
Subject(s)
MicroRNAs/genetics , Neuralgia/genetics , Peripheral Nerve Injuries/genetics , Potassium Channels, Tandem Pore Domain/metabolism , Animals , Constriction, Pathologic/genetics , Ganglia, Spinal/metabolism , Hyperalgesia/metabolism , Male , MicroRNAs/metabolism , Neuralgia/physiopathology , Peripheral Nerve Injuries/physiopathology , Potassium Channels, Tandem Pore Domain/genetics , Rats, Sprague-Dawley , Sciatic Nerve/injuries , Sciatic Neuropathy/metabolismABSTRACT
In recent years, immunotherapy, particularly PD-1 antibodies, have significantly enhanced the outcome of gastric cancer patients. Despite these advances, some patients do not respond well to treatment, highlighting the need to understand resistance mechanisms and develop predictive markers of treatment effectiveness. This study retrospectively analyzed data from 106 patients with stage IV gastric cancer who were treated with first-line immunotherapy in combination with chemotherapy. By comparing plasma cytokine levels between patients resistant and sensitive to PD-1 antibody therapy, the researchers identified elevated IL-4 expression in the resistant patients. Mechanical investigations revealed that IL-4 induces metabolic changes in macrophages that activate the PI3K/AKT/mTOR pathway. This alteration promotes ATP production, enhances glycolysis, increases lactic acid production, and upregulates FcγRIIB expression in macrophages. Ultimately, these changes lead to CD8+ T cell dysfunction and resistance to PD-1 antibody therapy in gastric cancer. These findings highlight the role of IL-4-induced macrophage polarization and metabolic reprogramming in immune resistance and verify IL-4 as potential targets for improving treatment outcomes in gastric cancer patients.
Subject(s)
Immunotherapy , Interleukin-4 , Macrophages , Receptors, IgG , Signal Transduction , Stomach Neoplasms , Up-Regulation , Humans , Interleukin-4/metabolism , Macrophages/metabolism , Macrophages/immunology , Receptors, IgG/metabolism , Immunotherapy/methods , Stomach Neoplasms/pathology , Stomach Neoplasms/metabolism , Stomach Neoplasms/immunology , Stomach Neoplasms/therapy , Male , Drug Resistance, Neoplasm/drug effects , Female , Receptors, Interleukin-4/metabolism , Middle Aged , Animals , AgedABSTRACT
Gastric carcinoma (GC) is regarded as one of the deadliest cancer characterized by diversity and haste metastasis and suffers limited understanding of the spatial variation between primary and metastatic GC tumors. In this project, transcriptome analysis on 46 primary tumorous, adjacent non-tumorous, and metastatic GC tissues was performed. The results demonstrated that metastatic tumorous tissues had diminished CD8+ T cells compared to primary tumors, which is mechanistically attributed to being due to innate immunity differences represented by marked differences in macrophages between metastatic and primary tumors, particularly those expressing ApoE, where their abundance is linked to unfavorable prognoses. Examining variations in gene expression and interactions indicated possible strategies of immune evasion hindering the growth of CD8+ T cells in metastatic tumor tissues. More insights could be gained into the immune evasion mechanisms by portraying information about the GC ecosystem.
Subject(s)
Stomach Neoplasms , Tumor Microenvironment , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Stomach Neoplasms/immunology , Humans , Tumor Microenvironment/immunology , Tumor Microenvironment/genetics , Neoplasm Metastasis , CD8-Positive T-Lymphocytes/immunology , RNA-Seq , Male , Female , Gene Expression Regulation, Neoplastic , Macrophages/immunology , Macrophages/metabolism , Macrophages/pathology , Prognosis , Middle Aged , Gene Expression Profiling , Single-Cell Gene Expression AnalysisABSTRACT
Prospero-related homeobox 1 (PROX1) is a homeobox transcription factor known to promote malignant transformation and stemness in human colorectal cancer (CRC). However, the biological function of PROX1 in metabolic rearrangement in CRC remains unclear. Here, we aimed to uncover the relationship between the expression profile and role of PROX1 and CRC cell glucose metabolism and to elucidate the underlying molecular mechanism. PROX1 expression was significantly upregulated in human CRC tissues and positively associated with the maximum standardized uptake value (SUVmax), a measure of tissue 18-fluoro-2-deoxy-D-glucose uptake and an indicator of glycolysis and tumor cell activity, in patients with CRC. Knockdown of PROX1 suppressed CRC cell proliferation and glucose metabolism in vitro and in vivo. Mechanistically, through a physical interaction, PROX1 recruited EZH2 to the SIRT3 promoter and inhibited SIRT3 promoter activity. Moreover, PROX1 or EZH2 knockdown decreased cell glycolysis by targeting SIRT3. Clinically, high PROX1 expression combined with low SIRT3 expression predicted poor prognosis in patients with CRC. Thus, our study suggests that the PROX1-EZH2 complex positively regulates cell proliferation and glucose metabolism by engaging SIRT3 in CRC, which may serve as a promising therapeutic strategy for CRC.
Subject(s)
Colorectal Neoplasms , Sirtuin 3 , Humans , Sirtuin 3/metabolism , Cell Line, Tumor , Transcription Factors/metabolism , Cell Proliferation/genetics , Colorectal Neoplasms/metabolism , Epigenesis, Genetic/genetics , Glucose/metabolism , Gene Expression Regulation, Neoplastic/geneticsABSTRACT
Gastric cancer (GC) is the fifth most commonly diagnosed cancer and usually has a dismal prognosis. Our previous study highlights the contribution of focal adhesion kinase (FAK) in the tumorigenesis of diffuse gastric cancer (DGC), a subtype of GC according to Lauren classification. The prognostic value of phosphorylated FAK (pFAK) in GC remains to be explored. To explore the prognostic value of pFAK, we retrospectively collected 176 formalin-fixed paraffin-embedded (FFPE) tumor tissues from GC patients who underwent D2 gastrectomy without neoadjuvant treatment. The immunohistochemistry (IHC) staining of pFAK was performed. Survival analysis was performed by Kaplan-Meier and risk factors were evaluated by Cox regression analysis. A pFAK-based nomogram was also constructed for the prediction of overall survival (OS). We demonstrated that the prognosis of pFAK-positive patients was worse than that of the pFAK-negative patients in GC (p = 0.010; hazard ratio [HR] = 1.777, 95% CI 1.131 to 2.791; median OS, 46.6 vs. 86.3 months, respectively), and positive pFAK was also an independent risk factor for the worse prognosis of GC (p = 0.0054; HR = 1.89, 95% CI 1.21-2.96). Moreover, the nomogram based on pFAK and other independent risk factors could improve predictive accuracy for prognosis of GC. In conclusion, through analysis of a large collection of clinically annotated GC samples, we demonstrate that pFAK is a negative prognostic factor in GC, and a nomogram integrating pFAK could help predict OS for GC patients.
ABSTRACT
BRAF V600E-mutant colorectal cancer (CRC) is a rare subtype of colorectal cancer with poor prognosis. Compelling evidence indicates that the heparanase (HPSE) gene has multiple functions in cancer, however, its role in BRAF V600E-mutant CRC remains elusive. Differentially expressed genes between BRAF V600E-mutant and wild-type patients were explored by analyzing public data from The Cancer Genome Atlas and the Gene Expression Omnibus. Clinical samples of 172 patients with BRAF V600E-mutant CRC diagnosed at Zhongshan Hospital Fudan University were collected. Overall survival was analyzed using Kaplan-Meier curves and Cox regression models. Cell models and xenografts were utilized to investigate the effect of HPSE on tumor proliferation. HPSE was significantly highly expressed in the BRAF V600E-mutant group. High HPSE expression level was independently associated with inferior survival in the BRAF V600E-mutant cohort. HPSE knockdown impeded tumor proliferation of BRAF V600E-mutant CRC cells in vitro and in vivo. Mechanistically, HPSE silencing arrested cell cycle in G0/G1 phase by downregulating Cyclin E2 expression via the AKT/p27Kip1 pathway. These findings support a role for HPSE in promoting BRAF V600E-mutant CRC progression, which suggests it holds great promise as a prognostic biomarker and a potential therapeutic target for the aggressive CRC subtype.
ABSTRACT
OBJECTIVE: To study the extractive technique of Polysaccharides from Polystictus Versicolor pretreated by super fine crushing. METHODS: Polystictus versicolor was pretreated by technique of super fine crushing, and the contrast examination of super powder (5 microm) and polystictus versicolor was done. Then the extractive technique of polysaccharides from polystictus versicolor super powder was optimized by the orthogonal design. RESULTS: The extraction yield of Polysaccharides from polystictus versicolor super powder was higher 61% than that of polystictus versicolor. The optimum extractive technique of polysaccharides was 100 degrees C, 80 min and extracting 3 times. CONCLUSION: Technique of super fine crushing is propitious to the extraction of polysaccharides from polystictus versicolor.