Role of LncRNA MIR99AHG in breast cancer: Bioinformatic analysis and preliminary verification.

Objective: This research was aimed to preliminarily explore the clinical roles and potential molecular mechanisms of MIR99AHG and its significant transcripts in breast cancer (BRCA). Methods: Public databases were utilized to analyze the expression and prognostic roles of MIR99AHG and its transcripts. Relationships between MIR99AHG expression and immune cells infiltration were analyzed in Xiantao platform. In addition, co-expressed genes and interacting proteins of MIR99AHG were predicted. CancerSEA analyzed its relationship with functional states. Next, CNV status, DNA methylation, interacting transcription factors (TFs) and ceRNA network were analyzed to explore its possible mechanisms. Then, RNA ISH and FISH assays were used to detect its expression and location in BRCA tissues and cell lines, respectively. Finally, qRT-PCR was utilized to investigate MIR99AHG expression in cell lines. Results: Compared with the corresponding normal tissues, MIR99AHG expression levels were lower in all BRCA subtypes, and luminal B's was the lowest one. And MIR99AHG expression was negatively related to the tumor stage. In addition, 4 transcripts (ENST00000619222.4, ENST00000418813.6, ENST00000602901.5 and ENST00000453910.5) of MIR99AHG showed significant differences in the expression. Databases also suggested that the high MIR99AHG expression levels indicated good prognosis, especially in patients without lymph node metastasis. Xiantao found that MIR99AHG was positively related to 17 immune cells and negatively linked with 2 immune cells. CancerSEA analysis showed no relationships between MIR99AHG and functional states. From GEPIA and BCIP databases, 19 co-expressed genes were highly related to these four significant transcripts of MIR99AHG. StarBase, RNAct and HDOCK showed that several tumor-associated proteins, including U2AF65, hnRNPC, AEBP2, CHIC1 and so on, might interact with MIR99AHG. Genetically, BRCA had a higher proportion of MIR99AHG CNV loss than CNV gain, and the high level of DNA methylation indicated a good prognosis. Furthermore, 19 TFs were predicted to combine with the promoter of MIR99AHG. Then, we screened out 10 miRNAs potentially interacting with the significant transcripts of MIR99AHG, and five were significantly increased in breast tumors compared to normal tissues, including miR-194-5p, miR-320 b and so on, which could combine 14 mRNAs. Through ISH and FISH assays, we verified that MIR99AHG was down-regulated in BRCA samples and cell lines in comparison to non-tumor tissues and mammary epithelial cell line (MCF10A), and MIR99AHG was located both in cytoplasm and nucleus. qRT-PCR assay also showed the lower expression of MIR99AHG in breast cancer cells than that in MCF10A. Conclusion: These results indicate that MIR99AHG can be a favorable prognostic indicator for BRCA. ENST00000619222.4, ENST00000418813.6, ENST00000602901.5 and ENST00000453910.5 are significant transcripts and their down-regulation may play crucial roles in the progression of BRCA.

Pan-cancer analysis of LncRNA XIST and its potential mechanisms in human cancers.

Background: X-inactive specific transcript (XIST), it has been found, is abnormal expression in various neoplasms. This work aims to explore its potential molecular mechanisms and prognostic roles in types of malignancies. Methods: This research comprehensively investigated XIST transcription across cancers from Oncomine, TIMER 2.0 and GEPIA2. Correlations of XIST expression with prognosis, miRNAs, interacting protens, immune infiltrates, checkpoint markers, mutations of tumor-associated genes and promoter methylation were also analyzed by public databases. In addition, 98 BRCA samples were collected to investigate XIST expression and evaluate its clinicopathological value. Results: In public databases, compared to normal tissues, XIST was lower in BRCA, CESC, COAD and so on, but increased in KIRC and PRAD. Databases also showed that XIST was a good indicator of prognosis in BRCA, COAD and so on, but a bad one in KIRC, KIRP and so on. From starBase, we found 29 proteins interacting with XIST, and identified 4 miRNAs which might be sponged by XIST in cancers. Furthermore, XIST was linked with immune infiltration, especially T cell CD4+, and was related to over 20 immune checkpoint markers. Moreover, several tumor-associated gene mutations and promoter methylation were negatively related to its expression. In addition, IHC showed that XIST in BRCA was obviously lower in comparison of normal tissues and was negatively related to lymph node invasion and TNM stage. Conclusion: In summary, abnormal expression of XIST influenced prognosis, miRNAs and immune infiltration across cancers, especially BRCA.

Roles of eIF3m in the tumorigenesis of triple negative breast cancer.

BACKGROUND: Without targets, triple negative breast cancer (TNBC) has the worst prognosis in all subtypes of breast cancer (BC). Recently, eukaryotic translation initiation factor 3 m (eIF3m) has been declared to be involved in the malignant progression of various neoplasms. The aim of this study is to explore biological functions of eIF3m in TNBC. METHODS: Multiple databases, including Oncomine, KM-plotter and so on, were performed to analyze prognosis and function of eIF3m in TNBC. After transfection of eIF3m-shRNA lentivirus, CCK-8, colony formation assay, cell cycle analysis, wound healing assay, transwell assays, mitochondrial membrane potential assay and cell apoptosis analysis were performed to explore the roles of eIF3m in TNBC cell bio-behaviors. In addition, western blotting was conducted to analyze the potential molecular mechanisms of eIF3m. RESULTS: In multiple databases, up-regulated eIF3m had lower overall survival, relapse-free survival and post progression survival in BC. EIF3m expression in TNBC was obviously higher than in non-TNBC or normal breast tissues. Its expression in TNBC was positively related to differentiation, lymph node invasion and distant metastasis. After knockdown of eIF3m, cell proliferation, migration, invasion and levels of mitochondrial membrane potential of MDA-MB-231 and MDA-MB-436 were all significantly suppressed, while apoptosis rates of them were obviously increased. In addition, eIF3m could regulate cell-cycle, epithelial-mesenchymal transition and apoptosis-related proteins. Combined with public databases and RT-qPCR, 14 genes were identified to be modulated by eIF3m in the development of TNBC. CONCLUSIONS: eIF3m is an unfavorable indicator of TNBC, and plays a vital role in the process of TNBC tumorigenesis.

Roles and correlation of FOXA1 and ZIC1 in breast cancer.

The aim of this study was to evaluate the prognostic role of Forkhead box A1 (FOXA1) in breast cancer and determine the relationship between FOXA1 and zinc finger of the cerebellum 1 (ZIC1). BCIP, GEPIA, and Oncomine databases were used to detect expression of FOXA1 and assess prognostic roles of FOXA1 and ZIC1 in invasive breast tumors. A total of 113 female invasive breast cancer cases were collected to investigate FOXA1 and ZIC1 expression via immunohistochemistry. Twenty pairs of frozen-thawed tumors were used to select reliable indicators via western blotting and real-time quantitative polymerase chain reaction. In addition, Kaplan-Meier curves and Cox regression analysis were performed to analyze the overall survival (OS) and relapse-free survival. Multiple databases showed that FOXA1 expression was elevated in invasive breast cancer and negatively related to ZIC1. BCIP database also displayed a poor prognosis of high FOXA1 and low ZIC1. FOXA1 was positively associated with tumor size, grading, lymph node metastasis, and Tumor Node Metastasis (TNM) staging, while ZIC1 expression was negatively related to grading, lymph node metastasis, and TNM staging. In Kaplan-Meier and Cox regression analysis, FOXA1 negative group and ZIC1 positive group had better OS rate and recurrence-free survival rate. In addition, a joint evaluation showed that "FOXA1- ZIC1+" had the highest OS and relapse-free survival, but "FOXA1+ ZIC1-" had the lowest ones. FOXA1 was negatively related to ZIC1 in breast cancer and they had different roles in clinicopathology and prognosis. Combined examination of FOXA1 and ZIC1 could bring more benefit to breast cancer patients.

High Survivin and Low Zinc Finger of the Cerebellum 1 Expression Indicates Poor Prognosis in Triple-negative Breast Carcinoma.

PURPOSE: Triple-negative breast carcinoma (TNBC) is accompanied with high risk of metastasis and recurrence. The present study aimed to explore the clinicopathological and prognostic roles of putative tumor-related genes in patients with TNBC. METHODS: Thirty pairs of frozen-thawed tumors were used to select reliable indicators via real-time quantitative polymerase chain reaction (RT-qPCR). Then, 150 pathology specimens were used to evaluate the expression of proteins in TNBC through immunohistochemistry. In addition, Kaplan-Meier curves and Cox regression analysis were also performed to analyze the overall survival and disease-free survival. RESULTS: RT-qPCR results indicated that among all the proteins analyzed using fresh-frozen TNBC samples, the expression levels of only Survivin and zinc finger of the cerebellum 1 (ZIC1) were obviously different from those in the corresponding normal tissues. Survivin and ZIC1 expression had opposite effects on the clinicopathological diagnosis and prognostic assessment in TNBC patients. Further, there was a negative correlation between Survivin and ZIC1 expression. In addition, the "Survivin-positive ZIC1-negative group" was associated with histologic grade, lymph node metastasis, and TNM staging (p < 0.001) and this was also an independent factor for evaluating the prognosis of TNBC in patients. CONCLUSION: In summary, the expression levels of Survivin and ZIC1 in TNBC are different from those in normal tissues and are negatively correlated mutually. The combined detection of Survivin and ZIC1 expression levels could allow better comprehensive diagnosis and prognostic evaluation for TNBC patients.

High Oct4 predicted worse prognosis of right-sided colon cancer patients.

AIM: This present study was aimed to compare the role of Oct4 in left-sided colon cancer (LCC) with right-sided colon cancer (RCC). PATIENTS & METHODS: One hundred and fifty one pathology specimens, 68 frozen-thawed tumors and cell lines were used to evaluate the role of Oct4 in LCC and RCC through immunohistochemistry, western blot and real-time quantitative PCR. RESULTS: In LCC, positive expression of Oct4 was positively related to differentiation and Dukes stage (p < 0.01). Only in RCC, Oct4 expression was also positively related to lymphatic invasion and survival rates of 'negative group' were significantly higher. CONCLUSION: In summary, Oct4 was related to tumor differentiation and later Dukes stage in colon cancer, and was correlated with invasion of lymphatic only in RCC. In addition, Oct4 was a potential prognostic indicator in RCC.

Prognostic Value of NME1 (NM23-H1) in Patients with Digestive System Neoplasms: A Systematic Review and Meta-Analysis.

OBJECTIVE: There is a heated debate on whether the prognostic value of NME1 is favorable or unfavorable. Thus, we carried out a meta-analysis to evaluate the relationship between NME1 expression and the prognosis of patients with digestive system neoplasms. METHODS: We searched PubMed, EMBASE and Web of Science for relevant articles. The pooled odd ratios (ORs) and corresponding 95%CI were calculated to evaluate the prognostic value of NME1 expression in patients with digestive system neoplasms, and the association between NME1 expression and clinicopathological factors. We also performed subgroup analyses to find out the source of heterogeneity. RESULTS: 2904 patients were pooled from 28 available studies in total. Neither the incorporative OR combined by 17 studies with overall survival (OR = 0.65, 95%CI:0.41-1.03, P = 0.07) nor the pooled OR with disease-free survival (OR = 0.75, 95%CI:0.17-3.36, P = 0.71) in statistics showed any significance. Although we couldn't find any significance in TNM stage (OR = 0.78, 95%CI:0.44-1.36, P = 0.38), elevated NME1 expression was related to well tumor differentiation (OR = 0.59, 95%CI:0.47-0.73, P<0.00001), negative N status (OR = 0.54, 95%CI:0.36-0.82, P = 0.003) and Dukes' stage (OR = 0.43, 95%CI:0.24-0.77, P = 0.004). And in the subgroup analyses, we only find the "years" which might be the source of heterogeneity of overall survival in gastric cancer. CONCLUSIONS: The results showed that statistically significant association was found between NME1 expression and the tumor differentiation, N status and Dukes' stage of patients with digestive system cancers, while no significance was found in overall survival, disease-free survival and TNM stage. More and further researches should be conducted to reveal the prognostic value of NME1.

Prognostic Value of SPARC in Patients with Pancreatic Cancer: A Systematic Review and Meta-Analysis.

OBJECTIVE: There is a heated debate on whether the prognostic value of SPARC is favorable or unfavorable. Thus, we carried out a meta-analysis evaluating the relationship between SPARC expression and the prognosis of patients with pancreatic cancer. METHODS: We searched PubMed, EMBASE and Web of Science for relevant articles. The pooled hazard ratios (HRs) and corresponding 95%CI of overall survival (OS) were calculated to evaluate the prognostic value of SPARC expression in patients with pancreatic cancer. We also performed subgroup analyses. RESULTS: With 1623 patients pooled from 10 available studies, the incorporative HR showed an unfavorable prognosis of patients with pancreatic cancer in the multivariate analysis (HR = 1.55, 95%CI: 1.11-2.17, P = 0.01), but not in univariate analysis (HR = 1.41, 95%CI: 0.47-4.21, P = 0.54) and estimate (HR = 1.24, 95%CI: 0.72-2.13, P = 0.44). And this adverse impact could also be found in the subgroup analyses in multivariate analysis, especially in the stroma (HR = 1.53, 95%CI: 1.05-2.24, P = 0.03). However, the combined HR had the highly significant heterogeneity. No obvious publication bias was found. CONCLUSIONS: SPARC might be an unfavorable indicator in patients with pancreatic cancer, especially in the stroma. More and further researches should be conducted to reveal the prognostic value of SPARC.