Expression and Clinical Significance of CLCA2 in Pan-Cancer

SUMMARY: The calcium-activated chloride channel (CLCA2) performs a vital function in the intricate process of tumorigenesis. Using a bioinformatics analysis system, we conducted a pan-cancer investigation on CLCA2 to explore its association with tumor prognosis and its involvement in immunology. In order to achieve this objective, we examined the prognostic significance and expression level of CLCA2 in multiple cancer types using the TIMER and Sangerbox databases. The analysis of protein interaction networks revealed proteins linked to CLCA2. To investigate the potential biological functions and enrichment pathways of CLCA2 in cancer, the SangerBox and GSCA databases were utilized. Furthermore, the expression of CLCA2 in different cancer subtypes was evaluated during the analysis. Various functional conditions of cancer cells were then compared with CLCA2 in the CancerSEA database. Using online tools like TISIDB and Assistant for Clinical Bioinformatics, the investigation explored the link between CLCA2 and immune subtypes. Additionally, it assessed immune cell infiltration as part of the analysis. In addition, the application of GDSA was employed to investigate the predictive significance of CLCA2 in relation to drug sensitivity. The research outcomes uncovered abnormal expression patterns of CLCA2 in diverse tumor categories, with its expression level demonstrating a correlation with distinct subtypes of tumors. Strong associations have been observed between enhanced patient survival rates and CLCA2 in specific tumor types. There is a noteworthy connection observed among diverse tumor types, immune cell infiltration, immune subtypes, and CLCA2. The enrichment analysis of KEGG indicates that there may exist a connection between the expression of CLCA2 and renin secretion, pancreatic secretion, as well as other pathways in pan-cancer. CLCA2 appears to primarily activate pathways such as EMT (epithelial-mesenchymal transition), RAS/MAPK, RTK, apoptosis, TSC/mTOR, and PI3K/ AKT in pan-cancer. On the other hand, it seems to inhibit pathways like cell cycle, DNA damage, hormone AR, and hormone ER. Through single-cell functional analysis, it has been confirmed that CLCA2 is associated with diverse cellular functional states, encompassing DNA repair, EMT, hypoxia, invasion, metastasis, and quiescence. Furthermore, a substantial correlation has been observed between the expression of CLCA2 and drug sensitivity towards bosutinib, tipifarnib-P1, as well as other therapeutic agents. This research affirms that various cancer types express CLCA2 and its involvement in tumor advancement and immune penetration. CLCA2 possesses the capability to function as a noteworthy biomarker and target for therapeutic intervention in diverse cancer forms.

El canal de cloruro activado por calcio (CLCA2) desempeña una función vital en el proceso de tumorigénesis. Utilizando un sistema de análisis bioinformático, llevamos a cabo una investigación pan-cáncer en CLCA2 para explorar su asociación con el pronóstico tumoral y su participación en la inmunología. Para lograr este objetivo, examinamos la importancia pronóstica y el nivel de expresión de CLCA2 en múltiples tipos de cáncer utilizando las bases de datos TIMER y Sangerbox. El análisis de las redes de interacción de proteínas reveló proteínas vinculadas a CLCA2. Para investigar las posibles funciones biológicas y las vías de enriquecimiento de CLCA2 en el cáncer, se utilizaron las bases de datos SangerBox y GSCA. Además, durante el análisis se evaluó la expresión de CLCA2 en diferentes subtipos de cáncer. Luego se compararon varias condiciones funcionales de las células cancerosas con CLCA2 en la base de datos CancerSEA. Utilizando herramientas en línea como TISIDB y Assistant for Clinical Bioinformatics, la investigación exploró el vínculo entre CLCA2 y los subtipos inmunes. Además, evaluó la infiltración de células inmunitarias como parte del análisis y se empleó la aplicación de GDSA para investigar la importancia predictiva de CLCA2 en relación con la sensibilidad al fármaco. Los resultados de la investigación descubrieron patrones de expresión anormales de CLCA2 en diversas categorías de tumores, y su nivel de expresión demuestra una correlación con distintos subtipos de tumores. Se han observado fuertes asociaciones entre mayores tasas de supervivencia de los pacientes y CLCA2 en tipos de tumores específicos. Se observa una conexión notable entre diversos tipos de tumores, infiltración de células inmunitarias, subtipos inmunitarios y CLCA2. El análisis de enriquecimiento de KEGG indica que puede existir una conexión entre la expresión de CLCA2 y la secreción de renina, la secreción pancreática y otras vías en el pancáncer. CLCA2 parece activar principalmente vías como EMT (transición epitelial-mesenquimatosa), RAS/MAPK, RTK, apoptosis, TSC/mTOR y PI3K/AKT en pan-cáncer. Por otro lado, parece inhibir vías como el ciclo celular, el daño del ADN, la hormona AR y la hormona ER. Mediante análisis funcional unicelular, se ha confirmado que CLCA2 está asociado con diversos estados funcionales celulares, que abarcan la reparación del ADN, la EMT, la hipoxia, la invasión, la metástasis y la inactividad. Además, se ha observado una correlación sustancial entre la expresión de CLCA2 y la sensibilidad al fármaco hacia bosutinib, tipifarnib-P1, así como a otros agentes terapéuticos. Esta investigación indica que varios tipos de cáncer expresan CLCA2 y su participación en el avance tumoral y la penetración inmune. CLCA2 posee la capacidad de funcionar como un biomarcador notable y como un objetivo para la intervención terapéutica en diversas formas de cáncer.

An extensive analysis of the prognostic and immune role of FOXO1 in various types of cancer

Forkhead Box O1 (FOXO1) has been reported to play important roles in many tumors. However, FOXO1 has not been studied in pan-cancer. The purpose of this study was to reveal the roles of FOXO1 in pan-cancer (33 cancers in this study). Through multiple public platforms, a pan-cancer analysis of FOXO1 was conducted to obtained FOXO1 expression profiles in various tumors to explore the relationship between FOXO1 expression and prognosis of these tumors and to disclose the potential mechanism of FOXO1 in these tumors. FOXO1 was associated with the prognosis of multiple tumors, especially LGG (low grade glioma), OV (ovarian carcinoma), and KIRC (kidney renal clear cell carcinoma). FOXO1 might play the role of an oncogenic gene in LGG and OV, while playing the role of a cancer suppressor gene in KIRC. FOXO1 expression had a significant correlation with the infiltration of some immune cells in LGG, OV, and KIRC. By combining FOXO1 expression and immune cell infiltration, we found that FOXO1 might influence the overall survival of LGG through the infiltration of myeloid dendritic cells or CD4+ T cells. Functional enrichment analysis and gene set enrichment analysis showed that FOXO1 might play roles in tumors through immunoregulatory interactions between a lymphoid and a non-lymphoid cell, TGF-beta signaling pathway, and transcriptional misregulation in cancer. FOXO1 was associated with the prognosis of multiple tumors, especially LGG, OV, and KIRC. In these tumors, FOXO1 might play its role via the regulation of the immune microenvironment.

Role of Ferroptosis-related Gene GLS2 in Pan-cancer Prognosis and Immunity / 肿瘤防治研究

Objective To assess the role of the ferroptosis-associated gene GLS2 in the prognosis of pan-cancer and immunity using bioinformatics methods. Methods GLS2 expression levels in pan-cancer were profiled using publicly available databases: The Cancer Genome Atlas, GTEx, Cancer Cell Line Encyclopedia and the International Cancer Genome Consortium. The aim was to explore the role of GLS2 gene expression, gene variation survival analysis, immune infiltration, immune checkpoint related genes, TMB, and MSI in different tumors. Results Difference in GLS2 expression levels between cancer and paraneoplastic tissues was statistically significant in most cancer types, and the expression level was correlated with survival in these cancer types. A positive correlation was found between GLS2 expression and immune cell infiltration in multiple cancer types, and GLS2 expression level was positively correlated with TMB, MSI, and methylation, and its expression is an indicator for potential therapeutic response. Conclusion Pan-cancer analysis shows that the ferroptosis-related gene GLS2 can be used as a diagnostic and prognostic marker of clear cell carcinoma of kidney, adrenocortical carcinoma, lung adenocarcinoma, and pancreatic cancer.

Value of brain-expressed X-linked family genes in the diagnosis and prognosis prediction of pan-cancer / 肿瘤研究与临床

Objective:To investigate the differential expression of brain-expressed X-linked (BEX) family genes in pan-cancer and its value in diagnosis and prognosis of pan-cancer.Methods:RNA sequencing (RNA-seq) data, survival data, immune subtypes, the stem cell scores based on RNA and DNA methylation of 33 different tumors from The Cancer Genome Atlas (TCGA) database were downloaded from the online database of University of California, Santa Cruz (UCSC Xena) on April 10, 2022. The limma package of R software (V.4.2.0) was used to analyze the expression of BEX family genes in the TCGA database. The differential expression of BEX family genes in pan-cancer tissues and normal tissues was compared by using Wilcox test. Pan-cancer patients were divided into high expression group and low expression group according to the median expression level of BEX family genes; Kaplan-Meier survival analysis was used to evaluate the relationship between the expression of BEX family genes and the overall survival (OS) of patients; Cox proportional risk model was used to analyze the effect of the expression of BEX family genes on OS in pan-cancer patients and then the forest map was drawn. The correlation of the expression of BEX family genes with tumor microenviroment and tumor stem cells in pan-cancer patients was analyzed based on the correlation index Cor value. Spearman correlation analysis was used to analyze the correlation between the expression of BEX family genes and tumor microenviroment and cancer stem cell index in gastric cancer tissues. The RNA-seq of different tumor cell lines and drug sensitivity data download from the CellMiner database were used to analyze the correlation between the expression of BEX family genes and drug sensitivity. The correlation of pan-cancer and gastric cancer immune subtypes with the expression of BEX family genes was analyzed by using Kruskal test.Results:BEX3 was highly expressed in pan-cancer tissues in TCGA database, BEX2 and BEX4 were moderately expressed in pan-cancer tissues, and BEX1 and BEX5 were relatively low expressed in pan-cancer tissues. The expressions of BEX2, BEX3 and BEX4 were the highest in cholangiocarcinoma, the expression of BEX5 was the highest in endometrial neoplasms, and the expression of BEX1 was the highest in invasive breast cancer. Compared with normal tissue samples, the expressions of BEX family genes were up-regulated or down-regulated in various cancers (all P < 0.05). Survival analysis showed that the expressions of BEX family genes were associated with the OS of various cancers. Some tumor patients with high expressions of BEX1, BEX3, BEX4 and BEX5 had better OS compared with those with low expressions, and the differences were statistically significant (all P < 0.05). Other patients with high expression of BEX family genes had worse OS compared with those with low expressions, and the differences were statistically significant (all P < 0.05). Cox regression analysis showed that the high expression of BEX1 for stomach neoplasms; the high expression of BEX2 for acute myeloid leukemia, thymoma and endometrial neoplasms; the expression high of BEX3 for squamous cell carcinoma of head and neck,sarcoma, stomach neoplasms and endometrial neoplasms; the high expression of BEX4 for rectal adenocarcinoma, stomach neoplasms and endometrial neoplasms; the high expression of BEX5 for renal suspicious cell carcinoma and thymoma were risk factors for OS (all P < 0.05).The expression of BEX family genes was negatively correlated with the stromal score of most cancers (all P < 0.05), and positively correlated with the stem cell score (all P < 0.05). The expression of BEX family genes was negatively correlated with cancer stem cell index of gastric cancer ( P < 0.05), and was positively correlated with matrix score and estimated total score (all P < 0.05). Among different tumor cell lines in CellMiner database, BEX family genes were closely related to drug resistance of vemurafenib (Cor = -0.368, P = 0.004), Kahalide f (Cor = -0.391, P = 0.002), O-6-benzylguanine (Cor = -0.375, P = 0.003) and other drugs. All genes in the BEX family were related to the immune subtypes of pan-cancer and were highly expressed in C5 subtype (all P < 0.05).For gastric cancer, all genes showed high expression in the C3 subtype (all P < 0.05), except BEX5 ( P = 0.24). Conclusions:The expression of BEX family genes is closely related to the prognosis of pan-cancer patients, and has an impact on the tumor microenvironment, cancer stem cells and drug sensitivity. BEX family genes may be potential biomarkers for diagnosis and prognosis of pan-cancer.

FARSB stratifies prognosis and cold tumor microenvironment across different cancer types: an integrated single cell and bulk RNA sequencing analysis / 南方医科大学学报

OBJECTIVE@#Immunotherapy has brought significant clinical benefits to a subset of patients, but has thus far been disappointing in the treatment of immunologically "cold" tumors. Existing biomarkers that can precisely identify these populations are insufficient. In this context, a potential cold tumor microenvironment (TME) marker FARSB was investigated to reveal its impact on TME and patients' response to immunotherapy across pan-cancer.@*METHODS@#The expression levels and mutational landscape of FARSB in pan-cancer were investigated. Kaplan-Meier and univariate Cox regression analyses were applied to analyze the prognostic significance of FARSB. Pathways affected by FARSB were investigated by gene set enrichment and variation analysis. The relationship between FARSB expression and immune infiltration was examined using the TIMER2 and R packages. Single-cell RNA sequencing (scRNA-seq) data of several cancer types from GSE72056, GSE131907, GSE132465, GSE125449 and PMID32561858 were analyzed to validate the impact of FARSB on the TME. The predictive effect of FARSB on immunotherapy efficacy was explored in 3 immune checkpoint inhibitors (ICIs)- treated cohorts (PMID32472114, GSE176307, and Riaz2017).@*RESULTS@#FARSB expression was significantly higher in 25 tumor tissues than in normal tissues and was associated with poor prognosis in almost all tumor types. FARSB expression exhibited a strong association with several DNA damage repair pathways and was significantly associated with TP53 mutation in lung adenocarcinoma (P < 0.0001, OR=2.25). FARSB characterized a typical immune desert TME and correlated with impaired expression of chemokines and chemokines receptors. Large-scale scRNA-seq analysis confirmed the immunosuppressive role of FARSB and revealed that FARSB potentially shapes the cold TME by impeding intercellular interactions. In 3 ICI-treated cohorts, FARSB demonstrated predictive value for immunotherapy.@*CONCLUSION@#This study provides a pan-cancer landscape of the FARSB gene by integrated single-cell and bulk DNA sequencing analysis and elucidates its biological function to promote DNA damage repair and construct the immune desert TME, suggesting the potential value of FARSB as a novel marker for stratifying patients with poor immunotherapeutic benefits and "cold" TME.

STIP1 correlates with tumor immune infiltration and prognosis as a potential immunotherapy target: a pan-cancer bioinformatics analysis / 南方医科大学学报

OBJECTIVE@#To investigate the correlation of stress-inducible phosphoprotein 1 (STIP1) expression level with prognosis of different cancers and its potential role in immunotherapy.@*METHODS@#TCGA, TARGET and GTEx databases were used for bioinformatic analysis of STIP1 expression level and its prognostic value in different cancers. We also detected STIP1 expression immunohistochemically in 10 pairs of colorectal cancer and adjacent tissues. We further analyzed the correlation of STIP1 expression level with tumor mutational burden, microsatellite instability, immune cell infiltration, immune regulators and outcomes of different cancers. STIP1- related proteins were identified using protein- protein interaction (PPI) network analysis, and functional enrichment analysis was performed to analyze the regulatory pathways involving STIP1.@*RESULTS@#Bioinformatics analysis showed that STIP1 was highly expressed in most tumors compared with the normal tissues (P < 0.05), which was confirmed by immunohistochemistry of the 10 pairs of colorectal cancer tissues. STIP1 expression level was correlated with clinical stages of multiple cancers (P < 0.05), and in some cancer types, an upregulated STIP1 expression was correlated with a poor prognosis of the patients in terms of overall survival, disease-specific survival, disease-free survival and progression-free survival (P < 0.05). STIP1 expression was significantly correlated with tumor mutational burden, microsatellite instability, immune cell infiltration and immunomodulatory factors in most tumors (P < 0.05). PPI network analysis indicated that STIP1-related proteins included HSPA4, HSPA8, and HSP90AA1. KEGG enrichment analysis suggested that the high expression of STIP1 in liver cancer was related mainly with valerate metabolism, tryptophan metabolism, and butyrate metabolism pathways; HALLMARK enrichment analysis suggested high STIP1 expression in liver cancer was involved in bile acid and fatty acid metabolism.@*CONCLUSION@#STIP1 is up-regulated in multiple cancer types and its expression level is correlated with clinical tumor stage, tumor mutational burden, microsatellite instability, immune cell infiltration and immunomodulatory factors.

Pan-cancer analysis of the expression pattern of long non-coding RNA MIR22HG / 南方医科大学学报

OBJECTIVE@#To conduct a pan-cancer analysis of the expression of long non-coding RNA (lncRNA) MIR22HG and explore its association with clinical characteristics.@*METHODS@#We analyzed the expression of MIR22HG in different tumors and its association with clinical staging, lymph node metastasis, tumor mutation burden (TMB) and microsatellite instability (MSI) using R package based on the Cancer Genome Atlas (TCGA) datasets. The relationship between MIR22HG expression and infiltrating immune cells was analyzed using TIMER algorithm. The association of MIR22HG gene alteration frequency with the clinical outcomes was examined using cBioPortal online software. Data form Genomics of Drug Sensitivity in Cancer (GDSC) were used to analyze the relationship between MIR22HG and the sensitivity of chemotherapy drugs. We specifically analyzed MIR22HG expression in hepatocellular carcinoma (HCC) and its correlation with sorafenib treatment using GEO database and verified the results in 12 pairs of HCC specimens. Kaplan-Meier analysis was performed to analyze the correlation of MIR22HG with the outcomes of sorafenib treatment. We also tested the effects of MIR22HG overexpression and knockdown on IC50 of sorafenib in HCC cells.@*RESULTS@#MIR22HG was downregulated in most tumors (P < 0.05), where its deletion mutations were frequent, and associated with a poor prognosis (P < 0.05). In many tumors, MIR22HG expression level was correlated with clinical stage, lymph node metastasis, TMB, MSI, immune cell infiltration, immune checkpoint-related genes, and sensitivity to common chemotherapeutic drugs (P < 0.05). Among the 6 common infiltrating immune cells in cancers, neutrophil infiltration had the strongest correlation with MIR22HG expression level, especially in breast cancer, rectal cancer and kidney renal papillary cell carcinoma (P < 0.05). MIR22HG was downregulated in HCC in association with HCC progression (P < 0.05). In HCC patients, a low MIR22HG expression was associated with a favorable outcome after sorafenib treatment (HR=2.94, P=0.075) and was capable of predicting the response to sorafenib treatment (AUC=0.8095). Compared with the negative control, MIR22HG overexpression obviously reduced sorafenib sensitivity (with IC50 of 7.731 vs 15.61) while MIR22HG knockdown increased sorafenib sensitivity of HCC cells (with IC50 of 7.986 vs 5.085).@*CONCLUSION@#MIR22HG expression level is correlated with clinical stage, lymph node metastasis, TMB, MSI, immune cell infiltration, and chemosensitivity in most cancer, suggesting its potential as an immunotherapeutic target and also a prognostic biomarker for tumors.

Exploratory screening of potential pan-cancer biomarkers based on The Cancer Genome Atlas database / 北京大学学报(医学版)

OBJECTIVE@#To screen potential pan-cancer biomarkers based on The Cancer Genome Atlas (TCGA) database, and to provide help for the diagnosis and prognosis assessment of a variety of cancers.@*METHODS@#"GDC Data Transfer Tool" and "GDCRNATools" packages were used to obtain TCGA database. After data sorting, a total of 13 cancers were selected for further analysis. False disco-very rate (FDR) < 0.05 and fold change (FC) >1.5 were used as the differential expression criteria to screen genes and miRNAs that were up- or down-regulated in all the 13 cancers. In the receiver operating characteristic curve (ROC curve), the area under the curve (AUC), the best cut-off value and the corresponding sensitivity and specificity were used to reflect diagnostic significance. The Kaplan-Meier method was used to calculate the survival probability and then the log-rank test was performed. Hazard ratio (HR) was calculated to reflect prognostic evaluation significance. DAVID tool were used to perform GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis for differentially expressed genes. STRING and TargetScan tools were used to analyze the regulatory network of differentially expressed genes and miRNAs.@*RESULTS@#A total of 48 genes and 2 miRNAs were differentially expressed in all the 13 cancers. Among them, 25 genes were up-regulated, 23 genes and 2 miRNAs were down-regulated. Most differentially expressed genes and miRNAs had good ability to distinguish between the cases and controls, with AUC, sensitivity and specificity up to 0.8-0.9. Survival analysis results show that differentially expressed genes and miRNAs were significantly associated with patient survival in a variety of cancers. Most up-regulated genes were risk factors for patient survival (HR>1), while most down-regulated genes were protective factors for patient survival (0 < HR < 1). The enrichment analysis of GO and KEGG showed that the differentially expressed genes were mostly enriched in biological events related to cell proliferation. In the regulatory network analysis, a total of 13 differentially expressed genes and 2 differentially expressed miRNAs had regulatory and interaction relationships.@*CONCLUSION@#The 48 genes and 2 miRNAs that were differentially expressed in 13 cancers may serve as potential pan-cancer biomarkers, providing help for the diagnosis and prognosis evaluation of a variety of cancers, and providing clues for the development of broad-spectrum tumor therapeutic targets.

Pan-Cancer Analysis of DEAH-Box Helicase 16 Expression and Prognostic Significance / 中国医科大学学报

Objective To investigate the expression and prognostic significance of DEAH-box helicase (DHX16) by pan-cancer analysis. Methods The expression and prognostic significance of DHX16 were analyzed using the UALCAN web-portal. Gene ontology and kyoto encyclopedia of genes and genomes analyses of proteins interacting with DHX16 were performed using DAVID 6.8 functional annotation software. Results DHX16 was highly expressed in bladder urothelial carcinoma, head and neck squamous cell carcinoma, esophageal carcinoma, liver hepatocellular carcinoma, and cholangiocarcinoma (all P ＜ 0.001). Proteins interacting with DHX16 were located mainly in catalytic step 2 spliceosome, nucleoplasm, and cell membrane, and participated in mRNA splicing and processing, binding to poly (A) RNA and nucleic acids, and RNA helicase activity. Spliceosome, mRNA surveillance, RNA degradation, and transport pathways were implicated. Conclusion The high expression of DHX16 is helpful for the prognosis of bladder urothelial carcinoma prognosis, and unfavorable for prognoses of adrenocortical carcinoma, sarcoma, brain lower grade glioma, liver hepatocellular carcinoma, and acute myeloid leukemia. Thus, DHX16 may have value as a prognostic marker.