scholarly journals LncRNA RP11-19E11 is an E2F1 target required for proliferation and survival of basal breast cancer

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
A. Giro-Perafita ◽  
L. Luo ◽  
A. Khodadadi-Jamayran ◽  
M. Thompson ◽  
B. Akgol Oksuz ◽  
...  

AbstractLong non-coding RNAs (lncRNAs) play key roles in the regulation of breast cancer initiation and progression. LncRNAs are differentially expressed in breast cancer subtypes. Basal-like breast cancers are generally poorly differentiated tumors, are enriched in embryonic stem cell signatures, lack expression of estrogen receptor, progesterone receptor, and HER2 (triple-negative breast cancer), and show activation of proliferation-associated factors. We hypothesized that lncRNAs are key regulators of basal breast cancers. Using The Cancer Genome Atlas, we identified lncRNAs that are overexpressed in basal tumors compared to other breast cancer subtypes and expressed in at least 10% of patients. Remarkably, we identified lncRNAs whose expression correlated with patient prognosis. We then evaluated the function of a subset of lncRNA candidates in the oncogenic process in vitro. Here, we report the identification and characterization of the chromatin-associated lncRNA, RP11-19E11.1, which is upregulated in 40% of basal primary breast cancers. Gene set enrichment analysis in primary tumors and in cell lines uncovered a correlation between RP11-19E11.1 expression level and the E2F oncogenic pathway. We show that this lncRNA is chromatin-associated and an E2F1 target, and its expression is necessary for cancer cell proliferation and survival. Finally, we used lncRNA expression levels as a tool for drug discovery in vitro, identifying protein kinase C (PKC) as a potential therapeutic target for a subset of basal-like breast cancers. Our findings suggest that lncRNA overexpression is clinically relevant. Understanding deregulated lncRNA expression in basal-like breast cancer may lead to potential prognostic and therapeutic applications.

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Atif Ali Hashmi ◽  
Kashif Ali Hashmi ◽  
Muhammad Irfan ◽  
Saadia Mehmood Khan ◽  
Muhammad Muzzammil Edhi ◽  
...  

Abstract Objectives Ki67 is the most commonly used marker to evaluate proliferative index in breast cancer, however no cutoff values have been clearly defined for high ki67 index. Cancer management should be according to loco-regional profile; therefore, we aimed to determine ki67 index in 1951 cases of intrinsic breast cancer subtypes and its association with other prognostic parameters in our set up. Results Triple negative breast cancers showed highest ki67 index (mean 50.9 ± 23.7%) followed by Her2neu (mean 42.6 ± 21.6%) and luminal B cancers (mean 34.9 ± 20.05%). Metaplastic and medullary breast cancers significantly showed higher ki67 index as compared to ductal carcinoma, NOS. No significant association of ki67 index was noted with any of the histologic parameters in different subtypes of breast cancer expect for tumor grade. Although, ki67 index is a valuable biomarker in breast cancer, however no independent prognostic significance of ki67 could be established in our study.


2014 ◽  
Vol 32 (26_suppl) ◽  
pp. 39-39
Author(s):  
Camila Masias ◽  
Theresa H. Shao

39 Background: Breast cancer has been increasing in many Asian countries, as well as among Asian Americans. While many studies have examined breast cancer subtypes in African American and Caucasian populations, few have looked at tumor subtypes in the Asian population. We aimed to examine breast cancer subtypes in Chinese Americans. Methods: We identified all Chinese patients diagnosed with invasive breast cancers between 2005 and 2012 from the Cancer Registry of Mount Sinai Beth Israel, Mount Sinai St. Luke’s, and Roosevelt Hospitals. The following clinical data were collected for each patient: age at diagnosis, year of diagnosis, largest tumor size (cm), lymph node status, estrogen receptor (ER), progesterone receptor (PR) and HER2 status. Based on ER, PR, and HER2, patients were categorized into three molecular subtypes: 1) Hormone receptor (HR)+ (ER and/or PR positive, HER2 negative), HER2+ and triple negative (TN) (ER, PR, and HER2 negative). Descriptive variables were analyzed using one-way Anova test. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from logistic regression models. Results: There were 175 Chinese patients diagnosed with invasive breast cancers from 2005 to 2012. Median age at diagnosis was 54 (range 27-90). One hundred fourteen (65%) were HR+, 41 (23%) were HER2+, and 20 (11%) were TN. There were 59 (34%) patients diagnosed at age ≤ 50 and twelve patients (7%) were diagnosed at age < 40. There were more HER2+ and TN breast cancers diagnosed in women age ≤ 50 compared to age > 50, but the difference was not statistically significant. Women in the HR+ group were diagnosed at an older age compared to the other two subgroups (57 ± 12, 52 ± 8, and 52 ± 10 for HR+, HER2+, and TN, respectively, p = 0.036). Patients with TN breast cancers were more likely to have lymph node involvement compared to HR+ or HER2+ patients (p = 0.02). There was a trend of increasing prevalence of HER2+ breast cancer observed in recent years: 18.5% in 2005-2006, 23.8% in 2007-2008, 18.4% in 2009-2010, and 29.8% in 2011-2012. Conclusions: We observed a high proportion of breast cancer among young Chinese Americans as well as an increasing prevalence of HER2+ breast cancer in this population in recent years. Further studies are warranted.


2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Nicole J. Chew ◽  
Terry C. C. Lim Kam Sian ◽  
Elizabeth V. Nguyen ◽  
Sung-Young Shin ◽  
Jessica Yang ◽  
...  

Abstract Background Particular breast cancer subtypes pose a clinical challenge due to limited targeted therapeutic options and/or poor responses to the existing targeted therapies. While cell lines provide useful pre-clinical models, patient-derived xenografts (PDX) and organoids (PDO) provide significant advantages, including maintenance of genetic and phenotypic heterogeneity, 3D architecture and for PDX, tumor–stroma interactions. In this study, we applied an integrated multi-omic approach across panels of breast cancer PDXs and PDOs in order to identify candidate therapeutic targets, with a major focus on specific FGFRs. Methods MS-based phosphoproteomics, RNAseq, WES and Western blotting were used to characterize aberrantly activated protein kinases and effects of specific FGFR inhibitors. PDX and PDO were treated with the selective tyrosine kinase inhibitors AZD4547 (FGFR1-3) and BLU9931 (FGFR4). FGFR4 expression in cancer tissue samples and PDOs was assessed by immunohistochemistry. METABRIC and TCGA datasets were interrogated to identify specific FGFR alterations and their association with breast cancer subtype and patient survival. Results Phosphoproteomic profiling across 18 triple-negative breast cancers (TNBC) and 1 luminal B PDX revealed considerable heterogeneity in kinase activation, but 1/3 of PDX exhibited enhanced phosphorylation of FGFR1, FGFR2 or FGFR4. One TNBC PDX with high FGFR2 activation was exquisitely sensitive to AZD4547. Integrated ‘omic analysis revealed a novel FGFR2-SKI fusion that comprised the majority of FGFR2 joined to the C-terminal region of SKI containing the coiled-coil domains. High FGFR4 phosphorylation characterized a luminal B PDX model and treatment with BLU9931 significantly decreased tumor growth. Phosphoproteomic and transcriptomic analyses confirmed on-target action of the two anti-FGFR drugs and also revealed novel effects on the spliceosome, metabolism and extracellular matrix (AZD4547) and RIG-I-like and NOD-like receptor signaling (BLU9931). Interrogation of public datasets revealed FGFR2 amplification, fusion or mutation in TNBC and other breast cancer subtypes, while FGFR4 overexpression and amplification occurred in all breast cancer subtypes and were associated with poor prognosis. Characterization of a PDO panel identified a luminal A PDO with high FGFR4 expression that was sensitive to BLU9931 treatment, further highlighting FGFR4 as a potential therapeutic target. Conclusions This work highlights how patient-derived models of human breast cancer provide powerful platforms for therapeutic target identification and analysis of drug action, and also the potential of specific FGFRs, including FGFR4, as targets for precision treatment.


2016 ◽  
Author(s):  
Nao Hiranuma ◽  
Jie Liu ◽  
Chaozhong Song ◽  
Jacob Goldsmith ◽  
Michael Dorschner ◽  
...  

About 16% of breast cancers fall into a clinically aggressive category designated triple negative (TNBC) due to a lack of ERBB2, estrogen receptor and progesterone receptor expression1-3. The mutational spectrum of TNBC has been characterized as part of The Cancer Genome Atlas (TCGA)4; however, snapshots of primary tumors cannot reveal the mechanisms by which TNBCs progress and spread. To address this limitation we initiated the Intensive Trial of OMics in Cancer (ITOMIC)-001, in which patients with metastatic TNBC undergo multiple biopsies over space and time5. Whole exome sequencing (WES) of 67 samples from 11 patients identified 426 genes containing multiple distinct single nucleotide variants (SNVs) within the same sample, instances we term Multiple SNVs affecting the Same Gene and Sample (MSSGS). We find that >90% of MSSGS result from cis-compound mutations (in which both SNVs affect the same allele), that MSSGS comprised of SNVs affecting adjacent nucleotides arise from single mutational events, and that most other MSSGS result from the sequential acquisition of SNVs. Some MSSGS drive cancer progression, as exemplified by a TNBC driven by FGFR2(S252W;Y375C). MSSGS are more prevalent in TNBC than other breast cancer subtypes and occur at higher-than-expected frequencies across TNBC samples within TCGA. MSSGS may denote genes that play as yet unrecognized roles in cancer progression.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Xiaomei Li ◽  
Buu Truong ◽  
Taosheng Xu ◽  
Lin Liu ◽  
Jiuyong Li ◽  
...  

Abstract Background Accurate prognosis and identification of cancer subtypes at molecular level are important steps towards effective and personalised treatments of breast cancer. To this end, many computational methods have been developed to use gene (mRNA) expression data for breast cancer subtyping and prognosis. Meanwhile, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) have been extensively studied in the last 2 decades and their associations with breast cancer subtypes and prognosis have been evidenced. However, it is not clear whether using miRNA and/or lncRNA expression data helps improve the performance of gene expression based subtyping and prognosis methods, and this raises challenges as to how and when to use these data and methods in practice. Results In this paper, we conduct a comparative study of 35 methods, including 12 breast cancer subtyping methods and 23 breast cancer prognosis methods, on a collection of 19 independent breast cancer datasets. We aim to uncover the roles of miRNAs and lncRNAs in breast cancer subtyping and prognosis from the systematic comparison. In addition, we created an R package, CancerSubtypesPrognosis, including all the 35 methods to facilitate the reproducibility of the methods and streamline the evaluation. Conclusions The experimental results show that integrating miRNA expression data helps improve the performance of the mRNA-based cancer subtyping methods. However, miRNA signatures are not as good as mRNA signatures for breast cancer prognosis. In general, lncRNA expression data does not help improve the mRNA-based methods in both cancer subtyping and cancer prognosis. These results suggest that the prognostic roles of miRNA/lncRNA signatures in the improvement of breast cancer prognosis needs to be further verified.


2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Jonathan D. Marotti ◽  
Kristen E. Muller ◽  
Laura J. Tafe ◽  
Eugene Demidenko ◽  
Todd W. Miller

Background. Phosphatidylinositol-3,4,5-trisphosphate-dependent Rac exchange factor 1 (P-Rex1) has been implicated in cancer growth, metastasis, and response to phosphatidylinositol 3-kinase (PI3K) inhibitor therapy. The aim of this study was to determine whether P-Rex1 expression differs between primary and metastatic human breast tumors and between breast cancer subtypes. Design. P-Rex1 expression was measured in 133 specimens by immunohistochemistry: 40 and 42 primary breast tumors from patients who did versus did not develop metastasis, respectively, and 51 breast-derived tumors from metastatic sites (36 of which had matching primary tumors available for analysis). Results. Primary breast tumors showed significant differences in P-Rex1 expression based on receptor subtype. ER+ and HER2+ primary tumors showed higher P-Rex1 expression than primary triple-negative tumors. HER2+ metastases from all sites showed significantly higher P-Rex1 expression compared to other metastatic receptor subtypes. Solid organ (i.e., brain, lung, and liver) metastases showed higher P-Rex1 expression compared to bone metastases. Conclusions. P-Rex1 expression is increased in ER+ and HER2+ breast cancers compared to triple-negative tumors. P-Rex1 may be differentially expressed in metastatic tumors based on site and receptor status. The role of P-Rex1 in the development of breast cancer metastases and as a predictive biomarker of therapeutic response warrants further investigation.


2021 ◽  
Author(s):  
Sayra Dilmac ◽  
Nilay Kuscu ◽  
Ayse Caner ◽  
Sendegul Yildirim ◽  
Burcak Yoldas ◽  
...  

Abstract Breast cancer is the second most common cancer in women. In malignant breast cancers, tumor cells have the potential to metastasize to distant organs through the lymphatic system and blood circulation. The aim of this study is to evaluate the expression of SIRT1 and FoxO proteins in metastatic and nonmetastatic breast cancer cells and distant organs metastasis. In our study, SIRT1, p53, p21, and FoxO proteins have been evaluated in metastatic 4TLM and non-metastatic 67NR cell lines by immunocytochemistry in vitro and also in mice breast cancer model in vivo. Cells were orthotopically injected to mammary fat pads of 8-10 weeks old Balb/c female mice. Primary tumor, lung and liver tissues were removed and expressions of these proteins were evaluated by immunohistochemistry, western blot and RT-PCR. In addition, signal pathways that are related to SIRT and FoxO proteins were examined by using IPA core analysis. TCGA database was browsed for investigation of different genes.In primary tumors, SIRT1, p21, p53, E2F1 and FoxO expressions were higher in 67NR compared to 4TLM. In metastatic lung and liver tissues, the expression levels of SIRT1, FoxO1, FoxO3a and FoxO4 proteins were increased in 4TLM compared to 67NR. IPA and TCGA analysis have also revealed that SIRT1 and FoxO proteins are lower in primary tumors, but increased in metastatic stages. In conclusion, in primary tumors SIRT1 and FoxO expressions were decreased in 4TLM compared to 67NR. Moreover, SIRT1 and FoxO, especially expressed in metastatic cells. High level of FoxO expressions in metastatic stages in TNBC patients also supports its association with metastasis. Our findings suggest that SIRT1 and FoxO’s have crucial role in tumor progression metastatic process in breast cancer.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Ovidiu Balacescu ◽  
Loredana Balacescu ◽  
Oana Virtic ◽  
Simona Visan ◽  
Claudia Gherman ◽  
...  

Tumors act systemically to sustain cancer progression, affecting the physiological processes in the host and triggering responses in the blood circulating cells. In this study, we explored blood transcriptional patterns of patients with two subtypes of HER2 negative breast cancers, with different prognosis and therapeutic outcome. Peripheral blood samples from seven healthy female donors and 29 women with breast cancer including 14 triple-negative breast cancers and 15 hormone-dependent breast cancers were evaluated by microarray. We also evaluated the stroma in primary tumors. Transcriptional analysis revealed distinct molecular signatures in the blood of HER2− breast cancer patients according to ER/PR status. Our data showed the implication of immune signaling in both breast cancer subtypes with an enrichment of these processes in the blood of TNBC patients. We observed a significant alteration of “chemokine signaling,” “IL-8 signaling,” and “communication between innate and adaptive immune cells” pathways in the blood of TNBC patients correlated with an increased inflammation and necrosis in their primary tumors. Overall, our data indicate that the presence of triple-negative breast cancer is associated with an enrichment of altered systemic immune-related pathways, suggesting that immunotherapy could possibly be synergistic to the chemotherapy, to improve the clinical outcome of these patients.


Author(s):  
Romain Teinturier ◽  
Razan Abou Ziki ◽  
Loay Kassem ◽  
Yakun Luo ◽  
Lucie Malbeteau ◽  
...  

Abstract Purpose Menin, encoded by the MEN1 gene, was recently reported to be involved in breast cancers, though the underlying mechanisms remain elusive. In the current study, we sought to further determine its role in mammary cells. Methods Menin expression in mammary lesions from mammary-specific Men1 mutant mice was detected using immunofluorescence staining. RT-qPCR and western blot were performed to determine the role of menin in ERα expression in human breast cancer cell lines. ChIP-qPCR and reporter gene assays were carried out to dissect the action of menin on the proximal ESR1 promoter. Menin expression in female patients with breast cancer was analyzed and its correlation with breast cancer subtypes was investigated. Results Immunofluorescence staining revealed that early mammary neoplasia in Men1 mutant mice displayed weak ERα expression. Furthermore, MEN1 silencing led to both reduced ESR1 mRNA and ERα protein expression in MCF7 and T47D cells. To further dissect the regulation of ESR1 transcription by menin, we examined whether and in which way menin could regulate the proximal ESR1 promoter, which has not been fully explored. Using ChIP analysis and reporter gene assays covering − 2500 bp to + 2000 bp of the TSS position, we showed that the activity of the proximal ESR1 promoter was markedly reduced upon menin downregulation independently of H3K4me3 status. Importantly, by analyzing the expression of menin in 354 human breast cancers, we found that a lower expression was associated with ER-negative breast cancer (P = 0.041). Moreover, among the 294 ER-positive breast cancer samples, reduced menin expression was not only associated with larger tumors (P = 0.01) and higher SBR grades (P = 0.005) but also with the luminal B-like breast cancer subtype (P = 0.006). Consistent with our clinical data, we demonstrated that GATA3 and FOXA1, co-factors in ESR1 regulation, interact physically with menin in MCF7 cells, and MEN1 knockdown led to altered protein expression of GATA3, the latter being a known marker of the luminal A subtype, in MCF7 cells. Conclusion Taken together, our data provide clues to the important role of menin in ERα regulation and the formation of breast cancer subtypes.


2021 ◽  
Vol 4 (1) ◽  
pp. 39-44
Author(s):  
M.O. Bilych

Background. Breast cancer is the leading cancer type in women. Improvement in its management requires a continuous investigation of new tools for diagnosis and treatment. Biomarkers for breast cancer remain a field of great interest, despite existing knowledge. Extensive research recognizes the critical role played by tumor-infiltrating lymphocytes (TILs) in terms of prognosis and prediction, but much uncertainty still exists about the application of this biomarker in clinical practice. Thus, the purpose of this paper is to review recent researches about the role of TILs as a prognostic and predictive factor in the clinical management of breast cancer subtypes. Materials and methods. Eligible studies from Medline, Pubmed, Google Scholar (2010–2020) databases were analyzed and retrieved. Results. For primary tumors, a positive correlation was found between TILs and survival prognosis for HER2+ and TNBC subtypes, while for luminal subtypes it was a negative correlation. The predictive value of TILs in the neoadjuvant setting is established for HER2+, TNBC subtypes. In the case of using TILs as a predictive factor for HER2-targeted therapy, it remains a concern due to controversial data. For residual tumor, it is growing body of evidence about the positive correlation of TILs and prognosis for all subtypes, but data are limited. Conclusions. TILs were found to have prognostic and predictive value. However, due to the heterogeneity of breast cancer subtypes, TILs as a biomarker should be interpreted with caution. Further studies need to be carried out to determine the validity of making a clinical decision based on TILs count.


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