Epstein-Barr Virus In Breast Cancer Research Articles

Role of Epstein-Barr Virus in Breast Cancer: Correlation with Clinical Outcome and Survival Analysis.

Background: Breast cancer is the most prevalent cancer among women worldwide. The potential involvement of Epstein-Barr virus (EBV) in breast cancer pathogenesis has been a subject of debate, but its correlation with clinical outcomes remains uncertain. Methods: In this study, we collected 276 pathologically confirmed breast cancer tissue samples from the tissue bank of MacKay Memorial Hospital and the National Health Research Institutes in Taiwan. DNA was extracted from frozen tissue using The QIAamp DNA Mini Kit. The Taqman quantitative PCR method was employed to assess the EBV copy number per cell in these samples, using NAMALWA cells as a reference. We performed statistical analyses, including 2 × 2 contingency tables, Cox regression analysis, and Kaplan-Meier survival curves, to explore the association between clinicopathologic factors and survival outcomes in breast cancer patients. We analyzed both relapse survival, which reflects the period patients remain free from cancer recurrence post-treatment, and overall survival, which encompasses all-cause mortality. Results: Our results revealed a significant association between EBV status and relapse survival (hazard ratio: 2.75, 95% CI: 1.30, 5.86; p = 0.008) in breast cancer patients. However, no significant association was found in overall survival outcomes. Additionally, we observed significant associations between ER status and tumor histologic grade with both overall and relapse survival. Patients with EBV-positive tumors exhibited higher recurrence rates compared to those with EBV-negative tumors. Furthermore, we noted significant correlations between EBV status and HER-2 (p = 0.0005) and histological grade (p = 0.02) in our cohort of breast cancer patients. Conclusions: The presence of EBV in breast cancer tumors appears to exert an impact on patient outcomes, particularly concerning recurrence rates. Our findings highlight the significance of considering EBV status as a potential prognostic marker in breast cancer patients. Nonetheless, further research is essential to elucidate the underlying molecular mechanisms and develop novel therapeutic approaches.

Two Oncoviruses of HPV and EBV in Breast Cancer: An Iran-based Study

OBJECTIVE: To answer the question of whether viral infections such as Human papillomavirus (HPV) and Epstein-Barr virus (EBV) are involved in the occurrence of breast cancer or not. METHODOLOGY: In this case-control study, 50 paraffin-embedded breast samples (FFPE) and 50 non- cancerous FFPE samples were prepared from patients referred to Abadan hospitals from 2018 to 2021 to identify the genome of HPV and EBV by polymerase chain reaction (PCR). Data were analyzed using SPSS 15 with P-values of 0.05. Confirmed breast cancer biopsy samples with no medical history of chemotherapy and/or radiotherapy, the patient not being pregnant at the time of sampling, not using anti-cancer treatments, and not suffering from systemic inflammatory diseases such as rheumatoid arthritis. Patients of any age, with any breast cancer, and any size or stage of tumor were included without restrictions. RESULTS: Using PCR, HPV DNA was detected in 7/50 (14%) and 2/50(4%) of breast cancers and normal control, respectively. Moreover, 71.42% and 28.57% of HPV-infected persons in the patient's group were genotypes 16 and 18, respectively. All HPV-infected people in the control group were low-risk genotypes 26 and 53. Also, EBV DNA was found in 2/50 (4%) and 6/50 (12%) of breast cancers and control samples, respectively. Co-infection was not detected in samples. CONCLUSION: Although our study does not provide substantial Evidence about the role of viral infection in the progressiveness of breast tumors, significant studies have shown the critical role of these infections in the progression of breast tumors. KEYWORDS: Human Papillomavirus, HPV, Epstein–Barr virus, EBV, breast cancer

Epstein‑Barr virus as a promoter of tumorigenesis inthetumor microenvironment of breast cancer (Review).

Epstein‑Barr virus (EBV) is an oncovirus associated with various neoplasms, including breast cancer (BC). EBV‑associated oncogenesis requires the action of several viral molecules, such as EBV nuclear antigen 3C, latent membrane protein 1, microRNAs and long non‑coding RNAs, which are able of manipulating the cellular machinery, inducing an evasion of the immune system, blocking apoptosis processes, promoting cell survival and metastasis. The risk of developing cancer is associated with epigenetic alterations and alterations in various signaling pathways. The activation of all these molecules can modify the expression of EBV proteins with oncogenic activity, influencing the oncogenic process. It is clear that BC, being multifactorial, presents a greater complexity; in numerous cases, the infection associated with EBV may be crucial for this neoplasia, if particular conditions for both the virus and host are present. In the present review, all these variables are analyzed in an aim to improve the understanding of the participation of EBV in BC.

Prevalence of Epstein-Barr virus (EBV) in Iranian Breast Carcinoma Patients.

Introduction:Breast cancer (BC) is the most common malignancy affecting females worldwide. Various risk factors play a role in the developing of BC. Infectious agents like viruses have been proposed for this cancer and Epstein-Barr virus (EBV) is a widely researched candidate virus. This study detects the presence of EBV-DNA in breast cancer patients. Methods:The study was conducted on 59 formalin-fixed paraffin-embedded (FFPE) tissue blocks samples of women with breast carcinoma and 11 non-neoplastic breast controls. The DNA was extracted for all the samples. Then detection of EBNA1 EBV was done by polymerase chain reaction (PCR). Results:EBV was detected in 6.7% (4/59) of patients while all breast control samples were negative. All patients with positive EBV-DNA were high tumor grades (II, and III). Also, they had a low level of educations. Conclusions:According to our findings, it can be suggested that EBV may have a potential role in breast cancer development. However, this study provides substantial but not conclusive evidence for the involvement of viruses in BC disease development. Therefore, future investigations are needed to elucidate the exact role of EBV in breast cancer.

Molecular detection of Epstein-Barr virus in breast cancer among Sudanese female population: a case-control study

Background: Breast cancer is the most common cancer in women worldwide and in Sudan. Breast cancer occurs due to a multifactorial process and infection with an oncogenic virus has been recently investigated as a possible risk factor for breast cancer. For nearly two decades, studies have incriminated Epstein-Barr virus (EBV) in the etiology of breast cancer. However, the results are unconvincing, and their interpretation has remained a matter of debate. The aim of this study was to detect EBV in breast cancer biopsies obtained from Sudanese female patients. Methods: A descriptive, hospital-based, case-control study, conducted at Faculty of Medical Laboratory Science, University of Khartoum, Khartoum, Sudan. Archival blocks were obtained from 115 patients with breast cancer and 115 controls during the period between November 2016 till March 2017. Results: Among 115 breast cancer tissue specimens, EBV DNA was identified in 42/115 (36.5 %) samples and was not identified in 73/115 (63.5 %) tissue samples. The highest frequency of EBV detection was among 41–60 year-olds (23/42, 54.7 %), followed by 21–40 year-olds (12/42, 28.5 %) and 61–80 year-olds (5/42, 11.9 %). In the control group, the majority were diagnosed with fibroadenoma (70.4%), followed by fibrocystic changes (10.4%) and lactating changes (0.9%). Conclusion: The data obtained in this study demonstrated that EBV was present in a high percentage of our study population; however, the exact role of EBV in Sudanese breast cancer needs to be studied more in depth.

The Relationship Between EBV Virus and Breast Cancer in Khuzestan Province of Iran

Introduction: Many study results have suggested that infection by the Epstein-Barr virus is a possible agent of human breast cancer. But the role of Epstein-Barr virus in breast cancer is still controversial. Materials and Methods: Paraffin embedded formalin fixed specimens were prepared from 40 breast and 40 healthy tissues in Khuzestan province of Iran. After DNA extraction, the purity of all DNA samples was evaluated by amplification of constitutive beta-actin gene. Then the presence of EBV gene in DNA extraction with appropriate purity was assessed by polymerase chain reaction (PCR) using virus specific primers. Results: only 2 out 39 cases of tumor (5.12%) and none of the 37 healthy samples were positive for the presence of Epstein-Barr virus. Statistically, Cramer’s index for EBV infection was 0.160 in cancer samples. Conclusions: Our results indicated that there is no significant relationship between breast cancer and Epstein-Barr virus. Further investigation on more patients needed to determine the exact relationship between EBV and breast cancer in this province.

Association of Epstein - Barr virus and breast cancer in Eritrea

BackgroundThe oncogenic potential of Epstein-Barr virus (EBV) in breast cancer is being increasingly recognized. Despite some controversies regarding such role, new evidence is suggesting a culpability of EBV in breast cancer, particularly in Africa where the virus has been originally associated with causation of several solid and hematological malignancies. One example is a report from Sudan implicating EBV as a prime etiologic agent for an aggressive type of breast cancer, where nearly 100% of tumor tissues were shown to carry viral signatures. To get a broader view on such association, other nearby countries should be investigated. The present study aims to determine the prevalence and possible associations of the virus in Eritrean breast cancer patients.MethodsDetection of EBV genome using primers that target Epstein Barr Encoded RNA (EBER) gene and Latent Membrane Protein-1 (LMP-1) gene sequences was performed by polymerase chain reaction (PCR) on DNA samples extracted from 144 formalin fixed paraffin embedded breast cancer tissues and 63 non-cancerous breast tissue as control group. A subset of PCR positive samples was evaluated for EBER gene expression by in situ hybridization (ISH). Expression of Latent Membrane Protein-2a (LMP2a) was also assessed by immunohistochemistry in a subset of 45 samples.ResultsBased on PCR results, EBV genome signals were detected in a total of 40 samples (27.77%) as compared to controls (p-value = 0. 0031) with a higher sensitivity when using the EBER primers. Five out of the 14 samples stained by EBER-ISH 35.71% were positive for the virus indicating the presence of the viral genome within the tumor cells. Of those stained for IHC 7 (15.55%) were positive for LMP2a showing low viral protein frequency.ConclusionsBased on these findings it can be concluded that EBV in Eritrea is associated with a smaller subset of tumors, unlike neighboring Sudan, thus pointing to possible differences in population predisposition and diseases epidemiology.

Evidence for the association of Epstein-Barr Virus in breast cancer in Indian patients using in-situ hybridization technique.

Epstein-Barr Virus (EBV) is etiologically linked to Burkitt lymphoma (BL), nasopharyngeal carcinoma, post-transplant lymphomas, Hodgkin disease, and possibly other tumors. However, the association of oncogenic EBV with breast carcinoma (BC) is still controversial and a matter of debate. We aimed to study the presence of EBV genome in BC cases in Indian patients and its association with the clinicopathological features. The formalin fixed paraffin embedded tissues from 83 women with primary invasive BC were studied for the presence of EBV by in-situ hybridization (ISH) technique for Epstein-Barr Virus Encoded RNA (EBER) with appropriate controls. Correlation of EBER-ISH positivity with clinicopathological features was performed using Fisher exact test and P<.05 was considered as significant. Eighty-three BC cases were comprised of 47 (56.5%) triple negative breast cancers (TNBC), 17 (20.5%) hormone positive and 19 (22.9%) HER2 positive cases. Of 83 cases, 25 cases (30.1%) were positive for EBER-ISH test. The positivity was restricted to the tumor cells and not seen in the surrounding breast lobules. EBER-ISH positivity was statistically associated with larger tumor size (52.6% in >5 cm tumors vs 19.3% in ≤5 cm; P=.014) and with TNBCs (21/47 [44.7%] in TNBCs vs 4/36 [11.1%] in non-TNBCs; P=.001). A possible causal association of EBV in BC cases in Indian patients is suggested by high frequency of EBER-ISH positivity noted in our study. This might have therapeutic significance because of the possible role of EBV specific cytotoxic T cells in targeting EBV associated tumor cells and can be considered as a potential targeted therapy. To the best of our knowledge, this is the first study from India to address this issue using EBER-ISH technique.

Variation in risk and outcomes of Epstein-Barr virus-associated breast cancer by epidemiologic characteristics and virus detection strategies: an exploratory study.

A relationship of Epstein-Barr virus (EBV) and breast cancer etiology and outcome may have clinical utility and potential to enhance understanding of tumor biology. Research to date has yielded variable results, likely reflecting differing virus detection assays and unaddressed epidemiologic heterogeneity across studies. Applying our novel, five-target assay detection strategy in an exploratory study, we examined demographic, clinical, and tumor characteristics, and overall survival, associated with EBV positivity in breast adenocarcinomas from 59 non-Hispanic white and 68 Hispanic women sampled by age (<50, 50+) and stage (localized, regional/remote) and examined associations based on single assay targets. EBV was localized only to lymphocytes. Nevertheless, viral prevalence, although low, varied across patient subgroups. Adjusted odds ratios (OR) for EBV positivity were lower for younger Hispanic than white women (p interaction = 0.05), and marginally higher for larger [OR (95% confidence intervals) 1.03 (1.00-1.05) per mm increase] and right-sided [2.8 (0.97-7.8)] tumors. In whites, ORs were marginally higher for larger tumors [1.04 (1.00-1.07)] and marginally lower for age 50+ [0.24 (0.06-1.03)]; in Hispanics, ORs were higher for ER negative [5.6 (1.1-30.5)], and marginally higher for right-sided, tumors [5.8 (0.94-36.2)]. Survival was suggestively poorer for EBV-positive than EBV-negative tumors in older women with localized disease. EBV associations differed across single assay targets, indicating variation in prior findings likelydue to assay performance. The differing EBV associations by age and race/ethnicity suggest a non-random role of EBV in breast cancer and support further study using multi-target assays, relevant epidemiologic design, and a larger study sample.

Abstract P4-10-01: Evaluation of the role of EBV in breast cancer

Abstract Background: A number of factors, both modifiable and non-modifiable, are associated with increased risk of developing breast cancer. Although these factors may help predict risk and prognosis, these known factors are imperfect and suggest that additional factors exist that promote the development and behavior of breast cancer. The Epstein-Barr virus (EBV), which is associated with tumor types such as Burkitt’s lymphoma and gastric cancer, may contribute to breast cancer development and/or progression, however, current research has led to mixed results, with some groups finding a positive correlation between EBV and breast cancer and others failing to find an association. Methods: The Clinical Breast Care Project database was queried to identify patients with high-quality, research-grade frozen tumor specimens and serum samples available. Previous exposure to EBV was determined using the Epstein-Barr virus (EBNA) IgG Human ELISA Kit. EBV, B-cells and macrophages were detected by immunofluorescence (IF) in seropositive patients using probes for EBNA1, CD-68 and CD-20, respectively. EBV and B-cell status was scored as present or absent while macrophages were classified as sparse, focal (weak, moderate or strong expression) or disseminated (macrophages detected throughout the tumor and stroma). Results: ELISA analysis on 211 serum samples found that 202 (96%) patients were seropositive for past EBV exposure. IF data has been generated for 31 tumors, from which six had no detectable B-cells. Of the remaining B-cell positive tumors, 32% (8/25) were positive for EBNA1 within the B-cells. Distribution of intrinsic subtypes was similar between both EBV+ and EBV- tumors, however, diagnosis with a late-stage tumor and lymph node metastasis was higher in EBV+ (50% stage III/IV, 88% lymph node positive) compared to EBV- tumors (24% stage III/IV, 47% lymph node positive). In addition, EBV+ tumors were more likely to have sparse/focal(weak) macrophage staining (63%) compared to EBV- tumors (47%). Conclusions: These data demonstrate that latent EBV is present within B-cells in a significant number of invasive breast tumors. Decreased detection of macrophages within the tumor component supports the theory that expression of EBV proteins impairs the function and maturation of macrophages, thus impairing immune surveillance and creating a pro-tumorigenic environment. This altered immune response may contribute to the later stage and increased frequency of metastasis in patients with EBV positive B-cells within the tumor microenvironment. Citation Format: Rachel E Ellsworth, Jill D Henning, Nikki Oakes, Allyson L Valente, Brednda Deyarmin, Jeff Meyer, Matthew T Hueman, Craig D Shriver. Evaluation of the role of EBV in breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P4-10-01.

Cytomegalovirus and Epstein-Barr virus in breast cancer.

Findings of polymerase chain reaction (PCR) studies of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) and breast cancer vary, making it difficult to determine whether either, both, or neither virus is causally associated with breast cancer. We investigated CMV and EBV in paired samples of breast cancer and normal breast tissue from 70 women using quantitative PCR. A serum sample from each woman was tested for CMV and EBV IgG. To place our results in context, we reviewed the existing literature and performed a meta-analysis of our results together with previous PCR studies of EBV, CMV, and breast cancer. Of the serology samples, 67 of 70 (96%) were EBV IgG positive and 49 of 70 (70%) were CMV IgG positive. QPCR detected EBV in 24 (34%) of the tumour and 9 (13%) of the paired normal specimens and CMV in 0 (0%) of the tumour and 2 (3%) of the paired normal specimens. Our findings, together with earlier results summarised in the meta-analysis, suggest several possibilities: variable findings may be due to limitations of molecular analyses; ‘hit and run’ oncogenesis may lead to inconsistent results; one or both viruses has a role at a later stage in breast cancer development; infection with multiple viruses increases breast cancer risk; or neither virus has a role. Future studies should focus on ways to investigate these possibilities, and should include comparisons of breast cancer tissue samples with appropriate normal tissue samples.

58P Detection of Human Papillomavirus and Epstein-Barr Virus in Breast Cancer

ABSTRACT Aim of the study Breast cancer is the most common malignancy diagnosed in the world's populations. Oncogenic viruses such as human papillomavirus have been identified in benign and cancerous breast tissues which are considered as an involving factor in the etiology of breast cancer. An oncogenic role for Epstein-Barr virus (EBV) in B cell lymphoma and nasopharyngeal cancer has been proposed. The relationship between EBV and breast cancer is not known yet. The purpose of this study was investigation of the presence of human papillomavirus (HPV) and EBV in Iranian patients with breast cancer. Materials and methods Paraffin blocks from 64 female patients with breast cancer and 53 non-cancerous breast tissues (Fibrocystic) as a control, were collected from the Imam Khomeini Hospital and Sizdah Abaan. DNA was extracted according to manufacturer's protocol by kit (QIAGEN, Hilden, Germany). Quality of isolated DNA was checked with primers of beta globin gene by PCR. Then, the appropriate samples were selected. All samples, for detection of HPV DNA were amplified for conserved sequences of the GP5 / GP6 by Real-Time PCR. Then, all of them were evaluated for the presence of DNA-EBV by PCR. Results Based on gene amplification of beta globin, two cancerous tissues and one non-cancerous tumor sample were not suitable and excluded. For DNA- HPV, 3 of 52 breast tissues samples (5.76%) were positive but not detected in any samples of breast cancer. For DNA- EBV, 23 of 65 (35.38%) cases of breast cancer specimens and 11 of 53 (20.75%) control samples were positive for virus. Conclusion Our results are not confirming the role of HPV in breast cancer but for EBV our results were similar to other reports in the world, in which a prevalence of EBV between %30 and 50% is suggested in the association of invasive breast cancer and EBV infection. Most epidemiological, biological and molecular studies is necessary to clear mechanisms involved these virus in the process of carcinogenesis. Disclosure All authors have declared no conflicts of interest.

Molecular Detection of Epstein-Barr virus in Breast Cancer

Background: The association of Epstein Barr virus (EBV) with breast carcinomas (BCs) is still in controversy. The aim of this study was to clarify the association of EBV & BC in Egyptian females and to assess its role as potential contributor to the development and behavioral alteration of BC. Subjects & methods: EBV-DNA was detected using PCR on breast tissue from 40 female patients with primary invasive BC; ductal (n=32) and lobular (n=8) and 20 age matched females undergoing reduction mammoplasties as control. Results: EBV-DNA was detected in 8/40 (20%) BC specimens. On the other hand all control specimens were negative As regards prognostic factors, no association was observed between EBV-DNA and patients' age, menopausal status and steroid receptor expression. However, significant associations were detected between the presence of EBV-DNA and other poor prognostic factors. All of the EBV-DNA positive BC were significantly associated with positive nodal status, where 7/8 cases showed more than three tumor-positive LN involvement. In spite of the small number of invasive lobular carcinoma included in this study there was a significant correlation between this histological type of poor prognosis and EBV-DNA detection rate where 4/8 (50%) of them were positive for EBV-DNA compared to 4/32 (12.5%) detection rate in invasive ductal carcinoma. A significant correlation was found between EBV-DNA detection rate in BC and high tumor grade of invasive ductal carcinoma; (100%, 1/1) association with grade III versus (9.67%; 3/ 31) with grade II. Conclusions: our results demonstrated the presence of the EBV genome in a considerable subset of BC in Egyptian patients. The virus was more frequently associated with bad prognostic factors. This indicates that EBV may play a role in the development and behavioral alteration of some aggressive BC.

Molecular Detection of Epstein-Barr virus in Breast Cancer

Background: The association of Epstein Barr virus (EBV) with breast carcinomas (BCs) is still in controversy. The aim of this study was to clarify the association of EBV & BC in Egyptian females and to assess its role as potential contributor to the development and behavioral alteration of BC. Subjects & methods: EBV-DNA was detected using PCR on breast tissue from 40 female patients with primary invasive BC; ductal (n=32) and lobular (n=8) and 20 age matched females undergoing reduction mammoplasties as control. Results: EBV-DNA was detected in 8/40 (20%) BC specimens. On the other hand all control specimens were negative As regards prognostic factors, no association was observed between EBV-DNA and patients' age, menopausal status and steroid receptor expression. However, significant associations were detected between the presence of EBV-DNA and other poor prognostic factors. All of the EBV-DNA positive BC were significantly associated with positive nodal status, where 7/8 cases showed more than three tumor-positive LN involvement. In spite of the small number of invasive lobular carcinoma included in this study there was a significant correlation between this histological type of poor prognosis and EBV-DNA detection rate where 4/8 (50%) of them were positive for EBV-DNA compared to 4/32 (12.5%) detection rate in invasive ductal carcinoma. A significant correlation was found between EBV-DNA detection rate in BC and high tumor grade of invasive ductal carcinoma; (100%, 1/1) association with grade III versus (9.67%; 3/ 31) with grade II. Conclusions: our results demonstrated the presence of the EBV genome in a considerable subset of BC in Egyptian patients. The virus was more frequently associated with bad prognostic factors. This indicates that EBV may play a role in the development and behavioral alteration of some aggressive BC.

Possible role of EBV in breast cancer and other unusually EBV-associated cancers

Epstein–Barr virus (EBV) a ubiquitous gamma herpesvirus persists for life, generally without health consequences. However, it is associated with several well-recognized malignancies, such as Burkitt’s lymphoma and nasopharyngeal carcinoma. A growing list of malignancies has been proposed to be EBV-associated: most of which are consistently EBV-positive whereas others show inconsistent results. The possible contribution of EBV to the development and/or progression of different “non-classical” tumors is discussed in terms of putative “non-traditional’’ infection in EBV-related tumors.

Detection of Epstein-Barr virus in breast cancers with lymphoid stroma

the purpose of our work is to detect Epstein-Barr virus (EBV) in 2 types of breast cancer: medullary carcinoma and high grade invasive ductal carcinoma with lymphoid stroma. we proceeded to a retrospective study of 18 medullary carcinoma and 18 high grade invasive ductal carcinoma with lymphoid stroma. The detection of the virus was carried out by immunohistochemistry with anti-LMP2 antibody and by hybridization in situ by oligonucleotides EBER1 and EBER1. LMP1 as well as hybridization in situ were positive in 5 tumors (3 medullary carcinoma and 2 high grade invasive ductal carcinoma with lymphoid stroma). positivity was observed in tumor cells and neither in epithelial non tumoral ones nor in lymphoid cells. during numerous years, correlations between the replication of EBV and the appearance of a malignant phenotype were limited to nasopharyngeal carcinoma and to lymphoid cells. A controversy regarding the association of EBV with breast cancers has recently been reported in the literature. This cancer being very frequent, the involvement of EBV even in a small proportion of breast cancers could have important implications. Our results suggest a possible implication of EBV in these tumours but other studies are necessary.

Lytic viral replication as a contributor to the detection of Epstein-Barr virus in breast cancer.

Epstein-Barr virus (EBV) has an accepted association with the epithelial malignancy nasopharyngeal carcinoma and has also been reported in other more controversial carcinoma settings. Evaluation of EBV association with epithelial carcinomas such as breast cancer would benefit from a better understanding of the outcome of EBV infection of these cells. Cell-free preparations of a green fluorescent protein-expressing virus, BX1, were used to infect breast cancer cell lines, which were then examined for EBV gene expression and viral genome copy number. Reverse transcription-PCR analyses revealed that the cells supported a mixture of latency II and lytic EBV gene expression. Lytic Zta and BMRF1 protein expression was detected by immunohistochemistry, and DNA PCR analyses estimated an EBV copy number of 300 to 600 genomes per infected cell. Evidence for lytic EBV expression was also found in breast tissue, where reverse transcription-PCR analyses detected lytic Zta transcripts in 7 of 10 breast carcinoma tissues and 4 of 10 normal tissues from the same patients. Scattered cells immunoreactive for Zta protein were also detectable in breast carcinoma. Quantitative real-time PCR analysis of EBV-positive breast carcinoma tissues suggested that less than 0.1% of the cells contained viral genomes. We suggest that sporadic lytic EBV infection may contribute to PCR-based detection of EBV in traditionally nonvirally associated epithelial malignancies.

Detection of Epstein-barr virus in breast cancer by polymerase chain reaction

Detection of Epstein-barr virus in breast cancer by polymerase chain reaction

Epstein-Barr virus detection in ductal carcinoma of the breast.

Epstein-Barr virus detection in ductal carcinoma of the breast.

Epstein-Barr virus in breast cancers

Epstein-Barr virus in breast cancers