乳腺癌中CELF6的表达水平及其与预后的关系

目的:研究CELF6在乳腺癌组织与正常组织中的表达差异以及其在乳腺癌中的预后意义。方法:采用GEPIA分析乳腺癌组织与正常乳腺组织中CELF6的表达差异,免疫组化检测乳腺癌组织CELF6蛋白的表达。KM-plotter在线分析TCGA数据库中CELF6的表达差异与乳腺癌患者生存预后的关系,CCK8实验分析不同CELF6表达水平对乳腺癌细胞生长增殖的影响。结果:GEPIA在线软件分析结果显示乳腺癌CELF6表达较与正常组织显著降低(P0.001)。免疫组化检测结果显示乳腺癌患者的乳腺癌组织CELF6的阳性表达显著低于癌旁的正常组织。KM-plotter在线分析的生存曲线显示CELF6高表达的乳腺癌患者生存预后显著优于低表达者(P0.001)。CCK8实验显示敲低乳腺癌细胞MDA-MB-231中CELF6的表达,细胞增殖速度显著变快,而过表达CELF6的MDA-MB-231细胞的增殖速度减慢。结论:CELF6可能作为潜在的抑癌基因,在乳腺癌组织中低表达,与乳腺癌患者预后不良有关。     

Annexin A8 Identifies a Subpopulation of Transiently Quiescent c-Kit Positive Luminal Progenitor Cells of the Ductal Mammary Epithelium

We have previously shown that Annexin A8 (ANXA8) is strongly associated with the basal-like subgroup of breast cancers, including BRCA1-associated breast cancers, and poor prognosis; while in the mouse mammary gland AnxA8 mRNA is expressed in low-proliferative isolated pubertal mouse mammary ductal epithelium and after enforced involution, but not in isolated highly proliferative terminal end buds (TEB) or during pregnancy. To better understand ANXA8’s association with this breast cancer subgroup we established ANXA8’s cellular distribution in the mammary gland and ANXA8’s effect on cell proliferation. We show that ANXA8 expression in the mouse mammary gland was strong during pre-puberty before the expansion of the rudimentary ductal network and was limited to a distinct subpopulation of ductal luminal epithelial cells but was not detected in TEB or in alveoli during pregnancy. Similarly, during late involution its expression was found in the surviving ductal epithelium, but not in the apoptotic alveoli. Double-immunofluorescence (IF) showed that ANXA8 positive (+ve) cells were ER-alpha negative (−ve) and mostly quiescent, as defined by lack of Ki67 expression during puberty and mid-pregnancy, but not terminally differentiated with ∼15% of ANXA8 +ve cells re-entering the cell cycle at the start of pregnancy (day 4.5). RT-PCR on RNA from FACS-sorted cells and double-IF showed that ANXA8+ve cells were a subpopulation of c-kit +ve luminal progenitor cells, which have recently been identified as the cells of origin of basal-like breast cancers. Over expression of ANXA8 in the mammary epithelial cell line Kim-2 led to a G₀/G₁ arrest and suppressed Ki67 expression, indicating cell cycle exit. Our data therefore identify ANXA8 as a potential mediator of quiescence in the normal mouse mammary ductal epithelium, while its expression in basal-like breast cancers may be linked to ANXA8’s association with their specific cells of origin.     

Identification of prognostic biomarkers for breast cancer brain metastases based on the bioinformatics analysis

PurposeThe prognosis of breast cancer (BC) patients who develop into brain metastases (BMs) is very poor. Thus, it is of great significance to explore the etiology of BMs in BC and identify the key genes involved in this process to improve the survival of BC patients with BMs.Patients and methodsThe gene expression data and the clinical information of BC patients were downloaded from TCGA and GEO database. Differentially expressed genes (DEGs) in TCGA-BRCA and GSE12276 were overlapped to find differentially expressed metastatic genes (DEMGs). The protein-protein interaction (PPI) network of DEMGs was constructed via STRING database. ClusterProfiler R package was applied to perform the gene ontology (GO) enrichment analysis of DEMGs. The univariate Cox regression analysis and the Kaplan-Meier (K-M) curves were plotted to screen DEMGs associated with the overall survival and the metastatic recurrence survival, which were identified as the key genes associated with the BMs in BC. The immune infiltration and the expressions of immune checkpoints for BC patients with brain relapses and BC patients with other relapses were analyzed respectively. The correlations among the expressions of key genes and the differently infiltrated immune cells or the differentially expressed immune checkpoints were calculated. The gene set enrichment analysis (GSEA) of each key gene was conducted to investigate the potential mechanisms of key genes involved in BC patients with BMs. Moreover, CTD database was used to predict the drug-gene interaction network of key genes.ResultsA total of 154 DEGs were identified in BC patients at M0 and M1 in TCGA database. A total of 667 DEGs were identified in BC patients with brain relapses and with other relapses. By overlapping these DEGs, 17 DEMGs were identified, which were enriched in the cell proliferation related biological processes and the immune related molecular functions. The univariate Cox regression analysis and the Kaplan-Meier curves revealed that CXCL9 and GPR171 were closely associated with the overall survival and the metastatic recurrence survival and were identified as key genes associated with BMs in BC. The analyses of immune infiltration and immune checkpoint expressions showed that there was a significant difference of the immune microenvironment between brain relapses and other relapses in BC. GSEA indicated that CXCL9 and GPR171 may regulate BMs in BC via the immune-related pathways.ConclusionOur study identified the key genes associated with BMs in BC patients and explore the underlying mechanisms involved in the etiology of BMs in BC. These findings may provide a promising approach for the treatments of BC patients with BMs.     

Long intergenic noncoding RNA 00641 inhibits breast cancer cell proliferation,migration, and invasion by sponging miR-194-5p

Long noncoding RNAs have an essential role in the tumorigenesis of breast cancer (BC). Nonetheless, the consequences of long intergenic noncoding RNA 00641 (LINC00641) in BC remain unidentified. This study shows that LINC00641 expression level was decreased in BC tissues. LINC00641 expression level was negatively related to tumor size, lymph-node metastasis, as well as clinical stage. LINC00641 overexpression inhibited cell proliferation, migration, and invasion but stimulated apoptosis in BC cells. LINC00641 overexpression also remarkably reduced BC growth and metastasis in vivo. LINC00641 acts as a competitive endogenous RNA to sponge miR-194-5p. miR-194-5p level was higher in BC tissues and cells compared with normal-adjacent tissues and normal breast epithelial cell. miR-194-5p expression was negatively correlated with LINC00641 expression in BC tissues. miR-194-5p overexpression reversed the effects of LINC00641 on cell proliferation, cycle, apoptosis, migration, as well as invasion. In conclusion, LINC00641 inhibits BC cell proliferation, migration, as well as invasion by sponging miR-194-5p.     

Identification of pyroptosis-related lncRNAs for constructing a prognostic model and their correlation with immune infiltration in breast cancer

The inflammasome-dependent cell death, which is denoted as pyroptosis, might be abnormally regulated during oncogenesis and tumour progression. Long non-coding RNAs (LncRNAs) are pivotal orchestrators in breast cancer (BC), which have the potential to be a biomarker for BC diagnosis and therapy. The present study aims to explore the correlation between pyroptosis-related lncRNAs and BC prognosis. In this study, a profile of 8 differentially expressed lncRNAs was screened in the TCGA database and used to construct a prognostic model. The BC patients were divided into high- and low-risk groups dependent on the median cutoff of the risk score in the model. Interestingly, the risk model significantly distinguished the clinical characteristics of BC patients between high- and low-risk groups. Then, the risk score of the model was identified to be an excellent independent prognostic factor. Notably, the GO, KEGG, GSEA and ssGSEA analyses revealed the different immune statuses between the high- and low-risk groups. Particularly, the 8 lncRNAs expressed differentially in BC tissues between two risk subgroups in vitro validation. Collectively, this constructed well-validated model is of high effectiveness to predict the prognosis of BC, which will provide novel means that is applicable for BC prognosis recognition.     

Curcumin inhibits the growth of triple‐negative breast cancer cells by silencing EZH2 and restoring DLC1 expression

Enhancer of zeste homolog 2 (EZH2), an oncogene, is a commonly up‐regulated epigenetic factor in human cancer. Hepatocellular carcinoma deletion gene 1 (DLC1) is an antioncogene that is either expressed at low levels or not expressed in many malignant tumours. Curcumin is a promising anticancer drug that has antitumour effects in many tumours, but its mechanism of action is unclear. Our research demonstrated that EZH2 was up‐regulated in breast cancer (BC) tissues and cells, whereas DLC1 was down‐regulated, and the expression of EZH2 and DLC1 was negatively correlated in BC. By analysing the characteristics of clinical cases, we found that positive expression of EZH2 and negative expression of DLC1 may be predictors of poor prognosis in patients with triple‐negative breast cancer (TNBC). Moreover, knockdown of EZH2 expression restored the expression of DLC1 and inhibited the migration, invasion and proliferation, promoted the apoptosis, and blocked the cell cycle of MDA‐MB‐231 cells. Furthermore, we found that curcumin restored the expression of DLC1 by inhibiting EZH2; it also inhibited the migration, invasion and proliferation of MDA‐MB‐231 cells, promoted their apoptosis and blocked the cell cycle. Finally, xenograft tumour models were used to demonstrate that curcumin restored DLC1 expression by inhibiting EZH2 and also inhibited the growth and promoted the apoptosis of TNBC cells. In conclusion, our results suggest that curcumin can inhibit the migration, invasion and proliferation, promote the apoptosis, block the cycle of TNBC cells and restore the expression of DLC1 by inhibiting the expression of EZH2.     

TP73‐AS1 promotes breast cancer cell proliferation through miR‐200a‐mediated TFAM inhibition

P73 antisense RNA 1T (TP73‐AS1 or PDAM) is a long non‐coding RNA, which can regulate apoptosis through regulation of p53 signaling‐related anti‐apoptotic genes. An abnormal change of TP73‐AS1 expression was noticed in cancers. The effects of TP73‐AS1 in breast cancer (BC) growth and the underlying mechanism remain unclear so far. In the present study, the effect of TP73‐AS1 in BC cell lines and clinical tumor samples was detected so as to reveal its role and function. In the present study, TP73‐AS1 was specifically upregulated in BC tissues and BC cell lines and was correlated to a poorer prognosis in patients with BC. TP73‐AS1 knocking down suppressed human BC cell proliferation in vitro through regulation of TFAM. In our previous study, we demonstrated that miR‐200a inhibits BC cell proliferation through targeting TFAM; here we revealed that TP73‐AS1 could regulate miR‐200a through direct targeting. Moreover, TP73‐AS1 might compete with TFAM for miR‐200a binding thus to promote TFAM expression. Data from the present study revealed that TP73‐AS1 promoted BC cell proliferation through acting as a competing endogenous RNA (ceRNA) by sponging miR‐200a. In conclusion, we regarded TP73‐AS1 as an oncogenic lncRNA promoting BC cell proliferation and a potential target for human BC treatment.     

ANXA2 could act as a moderator of EGFR-directed therapy resistance in triple negative breast cancer

Triple negative breast cancer (TNBC) patients cannot benefit from EGFR-targeted therapy even though the EGFR is highly expressed, because patients exhibit resistance to these drugs. Unfortunately, the molecular mechanisms remain relatively unknown. ANXA2, highly expressed in invasive breast cancer cells, is closely related with poor prognosis, and acts as a molecular switch to EGFR activation. In this study, MDA-MB-231 cells and MCF7 cells were used. Our results showed that ANXA2 expression is inversely correlated with cell sensitivity to gefitinib. Knockdown of ANXA2 expression in MDA-MB-231 cells increased the gefitinib induced cell death. When ANXA2 was overexpressed in MCF7 cells, the gefitinib induced cell death was decreased. Furthermore, we demonstrated that phosphorylation of ANXA2 at Tyr23 is negatively correlated with the sensitivity of TNBC to gefitinib. Altogether, our results suggest a new role of ANXA2 in regulating sensitivity of TNBC MDA-MB-231 cells to the EGFR inhibitor gefitinib.     

Down‐regulation of Orai3 arrests cell‐cycle progression and induces apoptosis in breast cancer cells but not in normal breast epithelial cells

Breast cancer (BC) is the leading cancer in the world in terms of incidence and mortality in women. However, the mechanism by which BC develops remains largely unknown. The increase in cytosolic free Ca²⁺ can result in different physiological changes including cell growth and death. Orai isoforms are highly Ca²⁺ selective channels. In the present study, we analyzed Orai3 expression in normal and cancerous breast tissue samples, and its role in MCF‐7 BC and normal MCF‐10A mammary epithelial cell lines. We found that the expression of Orai3 mRNAs was higher in BC tissues and MCF‐7 cells than in normal tissues and MCF‐10A cells. Down‐regulation of Orai3 by siRNA inhibited MCF‐7 cell proliferation and arrested cell cycle at G1 phase. This phenomenon is associated with a reduction in CDKs 4/2 (cyclin‐dependent kinases) and cyclins E and D1 expression and an accumulation of p21^Waf1/Cip1 (a cyclin‐dependent kinase inhibitor) and p53 (a tumor‐suppressing protein). Orai3 was also involved in MCF‐7 cell survival. Furthermore, Orai3 mediated Ca²⁺ entry and contributed to intracellular calcium concentration ([Ca²⁺]_i). In MCF‐10A cells, silencing Orai3 failed to modify [Ca²⁺]_i, cell proliferation, cell‐cycle progression, cyclins (D1, E), CDKs (4, 2), and p21^Waf1/Cip1 expression. Our results provide strong evidence for a significant effect of Orai3 on BC cell growth in vitro and show that this effect is associated with the induction of cell cycle and apoptosis resistance. Our study highlights a possible role of Orai3 as therapeutic target in BC therapy. J. Cell. Physiol. 226: 542–551, 2011. © 2010 Wiley‐Liss, Inc.     

Identification of a 4‐mRNA metastasis‐related prognostic signature for patients with breast cancer

Metastasis‐related mRNAs have showed great promise as prognostic biomarkers in various types of cancers. Therefore, we attempted to develop a metastasis‐associated gene signature to enhance prognostic prediction of breast cancer (BC) based on gene expression profiling. We firstly screened and identified 56 differentially expressed mRNAs by analysing BC tumour tissues with and without metastasis in the discovery cohort (GSE102484, n = 683). We then found 26 of these differentially expressed genes were associated with metastasis‐free survival (MFS) in the training set (GSE20685, n = 319). A metastasis‐associated gene signature built using a LASSO Cox regression model, which consisted of four mRNAs, can classify patients into high‐ and low‐risk groups in the training cohort. Patients with high‐risk scores in the training cohort had shorter MFS (hazard ratio [HR] 3.89, 95% CI 2.53‐5.98; P < 0.001), disease‐free survival (DFS) (HR 4.69, 2.93‐7.50; P < 0.001) and overall survival (HR 4.06, 2.56‐6.45; P < 0.001) than patients with low‐risk scores. The prognostic accuracy of mRNAs signature was validated in the two independent validation cohorts (GSE21653, n = 248; GSE31448, n = 246). We then developed a nomogram based on the mRNAs signature and clinical‐related risk factors (T stage and N stage) that predicted an individual's risk of disease, which can be assessed by calibration curves. Our study demonstrated that this 4‐mRNA signature might be a reliable and useful prognostic tool for DFS evaluation and will facilitate tailored therapy for BC patients at different risk of disease.     

Overexpression of Annexin A2 promotes proliferation by forming a Glypican 1/c-Myc positive feedback loop: prognostic significance in human glioma

In order to set up a reliable prediction system for the tumor grade and prognosis in glioma patients, we clarify the complicated crosstalk of Annexin A2 (ANXA2) with Glypican 1 (GPC1) and demonstrate whether combined indexes of ANXA2 and GPC1 could improve the prognostic evaluation for glioma patients. We found that ANXA2-induced glioma cell proliferation in a c-Myc-dependent manner. ANXA2 increased the expression of GPC1 via c-Myc and the upregulated GPC1 further promoted the c-Myc level, forming a positive feedback loop, which eventually led to enhanced proliferation of glioma cells. Both mRNA and protein levels of ANXA2 were upregulated in glioma tissues and coincided with the overexpression of GPC1. Besides, we utilized tissue microarrays (TMAs) and immunohistochemistry to demonstrate that glioma patients with both high expression of ANXA2 and GPC1 tended to have higher rate of tumor recurrence and shorter overall survival (OS). In conclusion, the overexpression of ANXA2 promotes proliferation of glioma cells by forming a GPC1/c-Myc positive feedback loop, and ANXA2 together with its downstream target GPC1 could be a potential “combination biomarker” for predicting prognosis of glioma patients.Subject terms: CNS cancer, Prognostic markers     

长链非编码RNA RP11-214F16.8 促进乳腺癌细胞增殖

长链非编码RNAs (long non-coding RNAs, lncRNAs)在乳腺癌发生发展中的作用备受瞩目。本研究通过大数据分析发现,lncRNA RP11-214F16.8在乳腺癌组织中的表达量显著高于正常组织,且其表达量与乳腺癌患者预后负相关。因此,本文采用qRT-PCR技术,在收集的临床样本中验证RP11-214F16.8的表达,证实其在乳腺癌组织中相对表达量为5.65±0.72,其在癌旁组织中表达量为2.63±0.35,且RP11-214F16.8的表达量与乳腺癌瘤体大小和临床TNM分期相关。此外发现,RP11-214F16.8在乳腺癌细胞中的表达量高于正常乳腺上皮细胞。在乳腺癌MCF-7细胞中,过表达RP11-214F16.8后,MCF-7细胞的增殖能力显著增强。而在MDA-MB-231细胞中,敲低RP11-214F16.8的表达,获得相反的结果。进一步研究发现,RP11-214F16.8可上调细胞周期蛋白 D3、CDK4的表达,而下调p18蛋白表达量,进而加速细胞增殖。总之,RP11-214F16.8在乳腺癌中高表达,且促进乳腺癌细胞增殖,进而推动乳腺癌进程。这一研究发现,将为乳腺癌发生发展的网络机制研究提供新的理论依据。     

Annexin A4 is a possible biomarker for cisplatin susceptibility of malignant mesothelioma cells

Mesothelioma is a highly malignant tumor with a poor prognosis and limited treatment options. Although cisplatin (CDDP) is an effective anticancer drug, its response rate is only 20%. Therefore, discovery of biomarkers is desirable to distinguish the CDDP-susceptible versus resistant cases. To this end, differential proteome analysis was performed to distinguish between mesothelioma cells of different CDDP susceptibilities, and this revealed that expression of annexin A4 (ANXA4) protein was higher in CDDP-resistant cells than in CDDP-susceptible cells. Furthermore, ANXA4 expression levels were higher in human clinical malignant mesothelioma tissues than in benign mesothelioma and normal mesothelial tissues. Finally, increased susceptibility was observed following gene knockdown of ANXA4 in mesothelioma cells, whereas the opposite effect was observed following transfection of an ANXA4 plasmid. These results suggest that ANXA4 has a regulatory function related to the cisplatin susceptibility of mesothelioma cells and that it could be a biomarker for CDDP susceptibility in pathological diagnoses.     

PLCA8 suppresses breast cancer apoptosis by activating the PI3k/AKT/NF‐κB pathway

The cysteine‐rich lysosomal protein placenta‐specific 8 (PLAC8), also called onzin, has been shown to be involved in many types of cancers, and its role is highly dependent on cellular and physiological contexts. However, the precise function of PLAC8 in breast cancer (BC) progression remains unclear. In this study, we investigated both the clinical significance and biological functions of PLAC8 in BC progression. First, high PLAC8 expression was observed in primary BC tissues compared with adjacent normal tissues through immunohistochemistry analysis. The results of in vitro and in vivo assays further confirmed that PLAC8 overexpression promotes cell proliferation and suppress BC cell apoptosis, whereas PLAC8 silencing has the opposite effect. In addition, the forced expression of PLAC8 greatly induces cell migration, partially by affecting the EMT‐related genes, including down‐regulating E‐cadherin expression and facilitating vimentin expression. Further mechanistic analysis confirmed that PLAC8 contributes to cell proliferation and suppresses cell apoptosis in BC by activating the PI3K/AKT/NF‐κB pathway. The results of our study provide new insights into an oncogenic role of PLAC8 and reveal a novel PLAC8/ PI3K/AKT/NF‐κB pathway as a potential therapeutic target for BC.     

Aberrant expression of Arpin in human breast cancer and its clinical significance

Arpin (Arp2/3 complex inhibitor), a novel protein found in 2013, plays a pivotal role in cell motility and migration. However, the precise role of Arpin in cancer is unclear. This study investigated the expression of Arpin in breast cancer and evaluated its correlation with the characteristics of clinical pathology and prognosis of breast cancer patients. Immunohistochemistry (IHC) for Arpin protein was performed on formalin‐fixed, paraffin‐embedded 176 breast cancer tissues and 43 normal breast tissues while qRT‐PCR for Arpin mRNA with 104 paired tumour and paratumoural tissues from breast cancer patients respectively. The association of Arpin expression with clinical pathological features and survival was assessed in a retrospective cohort analysis of patients. The results showed that the expression of Arpin protein in cancer tissues was lower compared to that in normal breast and the expression of Arpin mRNA was also lower in cancer tissues than that in the matched paratumoural tissues. Among the 176 breast cancer patients, the lower expression of Arpin was significantly associated with advanced tumour, nodes and metastasis system stage, and the reduced Arpin expression was strongly associated with axillary lymph node metastasis using univariate and multivariate logistic regression analysis [odds ratio: 3.242; 95% confidence interval (CI): 1.526, 6.888; P < 0.05]. Furthermore, Arpin expression was an independent risk factor for recurrence‐free survival (HR: 0.373; 95% CI: 0.171, 0.813; P < 0.05). As Arpin expression was first examined in human breast cancer tissues with qRT‐PCR and IHC, our results suggest that Arpin downregulation may contribute to the initiation and development of breast cancer metastasis. Therefore, as a potential predictive marker, Arpin deserves future studies.     

Identification of PSMD7 as a prognostic factor correlated with immune infiltration in head and neck squamous cell carcinoma

Background: Recurrent locally advanced or metastatic head and neck squamous cell carcinoma (HNSCC) is associated with dismal prognosis because of its highly invasive behavior and resistance to conventional intensive chemotherapy. The identification of effective markers for early diagnosis and prognosis is important for reducing mortality and ensuring that therapy for HNSCC is effective. Proteasome 26S subunit, non-ATPase 7 (PSMD7) is an ATP-independent component of the 19S regulatory subunit. The prognostic value of PSMD7 and the association with immune infiltration in HNSCC remains unclear.Methods: The Sangerbox, Oncomine, UALCAN and Human Protein Atlas (HPA) databases were used to examine PSMD7 expression profiles in HNSCC. The CVCDAP was used to analysis the association of PSMD7 with the prognosis of patients with HNSCC. The mechanism was investigated with gene set enrichment analysis (GSEA). The association between expression of PSMD7 and immune infiltration in HNSCC was investigated using the Tumor Immune Estimation Resource (TIMER), TISIDB database and CIBERSORT algorithm.Results: PSMD7 expression was significantly up-regulated in HNSCC compared with relative normal tissues. In addition, up-regulated PSMD7 expression was associated with various clinicopathological parameters. High expression of PSMD7 suggested inferior survival of HNSCC patients. GSEA and CERES score indicated that PSMD7 was closely correlated with tumor-related signaling pathways and cell survival. Functional analyses revealed that PSMD7 was positively correlated with various infiltration levels. Moreover, PSMD7 influenced the prognosis of HNSCC patients partially via immune infiltration.Conclusion: Our findings suggest that PSMD7 is associated poor prognosis in patients with HNSCC and plays an important role in tumor-related immune infiltration.