Breast cancer is the most common neoplasia among women in developed countries. The risk factors of breast cancer can be distinguished in modifiable and unmodifiable factors and, among the latter, genetic factors play a key role. Copy number variations (CNVs) are genetic variants that are classified as rare when present in less than 1% of the healthy population. Since rare CNVs are often cause of diseases, over the last years, their contribution in carcinogenesis has become a relevant matter of study. E2F1 is a transcriptional factor that plays an important role in regulating cell cycle and apoptosis. Its double and conflicting role is the reason why it acts both as oncogene and as tumour suppressor, depending on cell context. Since anomalies in expression or in number of copies of E2F1 have been related to several cancers, we aimed to study number of germline copies of E2F1 in women with breast cancer in order to better elucidate their contribution as predisposing factor to this tumour.
We performed, hence, a retrospective study on 222 Italian women with breast cancer recruited from October 2002 to December 2007. TaqMan CNV assay and Real-Time PCR were carried out to analyse, respectively, E2F1 CNV and E2F1 expression in the subjects of the study. Chi square test or Fisher\'s exact test and Student\'s t-test were used to calculate the frequency of CNVs and differences in continuous variables between groups, respectively.
Intriguingly, we found that 10/222 (4.5%) women with breast cancer had more copies than controls (0/200, 0%), furthermore, the number of copies positively correlated with E2F1 gene expression in breast cancer tissue, suggesting that the constitutive gain of the gene could translate into an increased risk of genomic instability. Additionally, we found that altered E2F1 copies were present prevalently in the patients with contralateral breast cancer (20%) and all of them had a positive family history, both typically associated with hereditary cancer.
Our findings suggest that copy number variations of E2F1 might be a susceptibility factor for breast cancer, however, further studies on large cohorts are to be performed in order to better delineate the phenotype linked to the gain of E2F1 copies.

BACKGROUND: The pathogenesis of the abnormality of the immune system is still not clear at present. Chemosynthetic drugs, human or animal immune products and microbiological drugs are used as the main drugs in clinics currently, but these drugs have different side effects. So researchers turned to safer natural products in order to find immunomodulatory active substances from natural products and their extracts.
METHODS: Immunosuppressed mice were induced by cyclophosphamide and administered with Cordyceps militaris polypeptide (CMP) for the study on the effect of CMP on the immune function of mice and its mechanism. Based on the 1748 differential gene sets selected in our previous work, the transcription factors and their corresponding target genes were screened by integrating the TRED (Transcriptional Regulatory Element Database), a transcriptional factor-target gene regulatory network was constructed, then the role of transcription factors in the regulatory network was elucidated by statistically analyzing the key nodes, and finally, the correlation of network genes with diseases was analyzed by using the DAVID database.
RESULTS: The results of animal experiments showed that CMP could increase the immune organ indexes, the number of white blood cells, the degree of delayed allergy and the content of hemolysin in the serum of mice. CMP was found to be involved in the regulation of immune function in mice through genes Kdr, Spp1, Ptgs2, Rel, and Smad3, and transcription factors Ets1, E2f2 and E2f1. E2F2 and E2F1 are members of the E2F family, so we speculated that the E2F family might play an important role, and its main regulatory pathways were the PI3K-Akt signaling pathway and TNF signaling pathway.
CONCLUSIONS: CMP can improve the immunity of mice. CMP can regulate the immune function of mice through multiple genes and transcription factors, and may also play a role in immune-related diseases, such as cancer.

For penile cancer (PC) there are no known molecular predictors of lymphatic spread and/or chemoresistance.
To identify functional biomarkers that can predict malignant progression and treatment responsiveness.
We used four patient-derived PC cell lines and measured invasion and capillary tube formation, chemoresponsiveness, and mRNA and protein expression. Data were further validated in E2F1 transcription factor knockdown and overexpression experiments. We quantified E2F1 transcript levels in a set of nonmetastatic tumours (NM), metastasised primary tumours (PT), and lymph node metastases (M) from 24 patients. E2F1 immunohistochemistry was performed in another set of 13 PC biopsies.
Relationships between different parameters were analysed using Student t tests. Transcript levels in patient samples were compared using Mann-Whitney U tests. Significance was set at p<0.05.
In cell lines established from lymph node metastases, E2F1 was more abundantly expressed, pRB was inactivated, and CDK2, CDK4, and cyclins D and E were elevated in comparison to cells from primary PC. Overexpression of E2F1 enhanced migratory capacity and lymphatic endothelial tubule formation, while depletion reduced invasiveness and increased chemosensitivity. VEGFR-3 and VEGF-C and mesenchymal markers were upregulated by high E2F1. E2F1 was clearly upregulated in infiltrative and metastatic primary tumours and metastases (NM vs PT, p<0.05; NM vs M, p<0.0005). E2F1 Quick scores increased from grade I to grade III tumours. A limitation of the study is the small number of patients.
E2F1 is a driver of invasion and lymphatic dissemination and promotes chemoresistance. E2F1-related biomarkers might assist in stratifying PC patients for different treatment regimens.
The availability of penile cancer cell lines allows molecular research on the mechanisms underlying metastasis and chemotherapy. A critical pathway involved in both features has been identified and may lead to better patient stratification for treatment selection.

This study aims to investigate the roles of lncRNA ANRIL in epithelial-mesenchymal transition (EMT) by regulating the ATM-E2F1 signaling pathway in pancreatic cancer (PC). PC rat models were established and ANRIL overexpression and interference plasmids were transfected. The expression of ANRIL, EMT markers (E-cadherin, N-cadherin and Vimentin) and ATM-E2F1 signaling pathway-related proteins (ATM, E2F1, INK4A, INK4B and ARF) were detected. Small molecule drugs were applied to activate and inhibit the ATM-E2F1 signaling pathway. Transwell assay and the scratch test were adopted to detect cell invasion and migration abilities. ANRIL expression in the PC cells was higher than in normal pancreatic duct epithelial cells. In the PC rat models and PC cells, ANRIL interference promoted the expressions of INK4B, INK4A, ARF and E-cadherin, while reduced N-cadherin and Vimentin expression. Over-expressed ANRIL decreased the expression of INK4B, INK4A, ARF and E-cadherin, but raised N-cadherin and Vimentin expressions. By inhibiting the ATM-E2F1 signaling pathway in PC cells, E-cadherin expression increased but N-cadherin and Vimentin expressions decreased. After ANRIL was silenced or the ATM-E2F1 signaling pathway inhibited, PC cell migration and invasion abilities were decreased. In conclusion, over-expression of lncRNA ANRIL can promote EMT of PC cells by activating the ATM-E2F1 signaling pathway.

The mammalian E2F family of transcription factors comprises a group of 8 proteins, which either activate or repress transcription of numerous target genes, playing a role in cell-cycle progression and apoptosis. We have collectively investigated the immunohistochemical expression of E2F1, E2F2, and E2F4 transcription factors and their relation to cell kinetic parameters using serial section analysis in a series of 100 cases of human colorectal adenocarcinomas. E2F1 and E2F4 expressed nuclear immunopositivity in all cases. The range of their expression was 2% to 80% (mean 21% ± 15%) and 2% to 90% (mean 66% ± 20%), respectively. E2F2 was expressed in 41 cases at low levels (range, 1% to 5%, mean 2% ± 9%). A statistically significant direct association between E2F4 and cell proliferation, as expressed by high levels of Ki-67 labeling index, was shown. A mutually exclusive immunostaining pattern between E2F1 and E2F4 and a direct correlation of E2F1 and apoptosis were also highlighted. Our results point to a possible direct tumor-promoting role for E2F4 in the context of colorectal carcinogenesis. The inverse immunohistochemical relationship between E2F1 and E2F4 indicates a possible mechanistic interlink in colorectal cancer. Low expression of E2F2 may reflect functional redundancy between members of the E2F family, in this case between E2F1 and E2F2.

Multiple E2F1 phosphorylation sites have been described as targets of different kinases, yet their in vivo implication is uncertain. We previously reported that GSK3beta is able to phosphorylate E2F1 in vitro at Ser403 and Ser433. Recently, it has been shown that both residues are also direct targets of p38 MAP kinase. In order to determine whether Ser403 phosphorylation occurs in vivo and to elucidate its role in E2F1 transcription activity, we developed a phospho-E2F1(Ser403) antibody for use in in vivo detection studies. Our results demonstrate that endogenous E2F1 is phosphorylated in vivo on Ser403, however neither GSK3beta nor p38 MAP kinase are responsible for this event. E2F1 phosphorylation on Ser403 is induced after treatment with doxorubicin in a dose response manner. The transcriptional response of E2F1 to doxorubicin is lower in an E2F1 Ser/Ala403 mutated construct relative to the wild type, suggesting a role for Ser403 phosphorylation in DNA damage conditions. Comparative study between the expression of the bcl2 gene family induced by the wild type and E2F1 Ser/Ala403 mutant revealed a statistically different pattern between both conditions. These results suggest that phosphorylation of Ser403 could influence the selection and regulation of E2F1 target genes.

BACKGROUND: The authors analyzed the retinoblastoma (Rb) tumor-suppressor pathway in meningeal hemangiopericytomas (MHPCs).
METHODS: : Immunohistochemical detection of the Rb pathway proteins (Rb; E2F transcription factor 1 [E2F1]; cyclins D1, D3, and E; cyclin-dependent kinase 4 [CDK4]; and the CDK4 inhibitor p16/INKa) was followed by double immunofluorescence (DIF) staining and laser-scanning confocal microscopy (LSCM) in 11 MHPC specimens and from 4 specimens of recurrent disease from 1, 2, and 4 recurrences (total, 18 specimens).
RESULTS: : All specimens displayed Rb pathway alterations, including low or negative Rb protein expression (17 specimens), high Rb protein expression (1 specimen), and loss of p16/INK4a expression (17 specimens). High levels of positive cell-cycle regulators were observed for E2F1 (10 specimens), cyclin E (7 specimens), CDK4 (5 specimens), cyclin D3 (1 specimen), and cyclin D1 (1 specimen). DIF and LSCM revealed no or very weak Rb and E2F1 colocalization, indicating that Rb does not act as a growth suppressor. High levels of human mouse double-minute 2 (HDM2) expression were observed in a previous study of these tumors, and they displayed colocalization with E2F1 and Rb in the current study, which supports the argument that HDM2 activates E2F1 and inactivates Rb.
CONCLUSIONS: : The current findings demonstrated that loss of Rb and p16/INKa expression and high E2F1 expression indicate impairment of the Rb suppressor pathway. HDM2 colocalization with E2F1 and Rb also indicates that Rb suppressor pathway inactivation and transactivation of DNA synthesis genes may play pathogenic roles in MHPCs. High expression levels of cyclin E, cyclin D1, cyclin D3, and CDK4 were associated with Rb suppressor pathway neutralization.

OBJECTIVE: Primary nodal and extranodal diffuse large B-cell lymphoma (DLBCL) were investigated for the heterogeneity of histopathology and immunophenotype, and their relation to clinical stage, comparatively. Whether E2F1 can be used as a germinal center B cell (GCB) DLBCL marker was also discussed.
METHODS: Classification of histopathology and immunophenotype of 98 cases were studied by immunohistochemistry in tissue microarray.
RESULTS: Histopathologic morphology presented as: centroblastic (CB,88.8%, 87/98), immunoblastic (IB,5.1%, 5/98), anaplastic (ALCL,3.1%, 3/98), and T cell rich B cell lymphoma (TCRBCL,3.1%, 3/98). Of which, 31 cases were GCB DLBCL, 10 (20.8%, 10/48) nodal, and 21 extranodal (42%, 21/50, P=0.024). The rates of Stages I/II in nodal and extranodal area were 48.5% and 70%, respectively (P=0.015). The rate of Stage I/ II in GCB DLBCL (74.2%) were higher than in non-GCB DLBCL (50.7%, P=0.029). The CD10 positive rates were 36.8% and 17.1% in Stages I/II and III/IV, respectively, and had significant differences (P=0.033). The CD10 positive rates were 18.8% and 38% in nodal and extranodal area, respectively (P=0.035). The positive rates of E2F1 were 38.8% and 16.5% in GCB and non-GCB DLBCL, respectively, and had significant differences (P=0.016). The positive rate of E2F1 had positive relation with the expression of CD10 and Bcl-6 (P<0.05).
CONCLUSIONS: CB is the most type in 98 cases of DLBCL. The rate of GCB DLBCL was significant higher in extranodal than in nodal areas CD 10 can be used as a prognostic marker. The prognosis of GCB DLBCL is better than that of non-GCB DLBCL. The positive expression of E2F1 can be used as a marker of GCB DLBCL.

GINS, a heterotetramer of SLD5, PSF1, PSF2, and PSF3 proteins, is an emerging chromatin factor recognized to be involved in the initiation and elongation step of DNA replication. Although the yeast and Xenopus GINS genes are well documented, their orthologous genes in higher eukaryotes are not fully characterized. In this study, we report the genomic structure and transcriptional regulation of mammalian GINS genes. Serum stimulation increased the GINS mRNA levels in human cells. Reporter gene assay using putative GINS promoter sequences revealed that the expression of mammalian GINS is regulated by 17beta-Estradiol-stimulated estrogen receptor alpha, and human PSF3 acts as a gene responsive to transcription factor E2F1. The goal of this study is to present the current data so as to encourage further work in the field of GINS gene regulation and functions in mammalian cells.

Advances in high-throughput technologies, such as ChIP-chip, and the completion of human and mouse genomic sequences now allow analysis of the mechanisms of gene regulation on a systems level. In this study, we have developed a computational genomics approach (termed ChIPModules), which begins with experimentally determined binding sites and integrates positional weight matrices constructed from transcription factor binding sites, a comparative genomics approach, and statistical learning methods to identify transcriptional regulatory modules. We began with E2F1 binding site information obtained from ChIP-chip analyses of ENCODE regions, from both HeLa and MCF7 cells. Our approach not only distinguished targets from nontargets with a high specificity, but it also identified five regulatory modules for E2F1. One of the identified modules predicted a colocalization of E2F1 and AP-2alpha on a set of target promoters with an intersite distance of <270 bp. We tested this prediction using ChIP-chip assays with arrays containing approximately 14,000 human promoters. We found that both E2F1 and AP-2alpha bind within the predicted distance to a large number of human promoters, demonstrating the strength of our sequence-based, unbiased, and universal protocol. Finally, we have used our ChIPModules approach to develop a database that includes thousands of computationally identified and/or experimentally verified E2F1 target promoters.