[Expression of HIV-1 Reverse Transcriptase in Murine Cancer Cells Increases Mitochondrial Respiration].

Changes in metabolic pathways are often associated with the development of a wide range of pathologies. Increased glycolysis under conditions of sufficient tissue oxygen supply and its dissociation from the Krebs cycle, known as aerobic glycolysis or the Warburg effect, is a hallmark of many malignant neoplasms. Identification of specific metabolic shifts can characterize the metabolic programming of individual types of tumor cells, the stage of their transformation, and predict their metastatic potential. Viral infection can also alter the metabolism of cells to support the process of viral replication. Infection with human immunodeficiency virus type 1 (HIV-1) is associated with an increased incidence of various cancers, and for some viral proteins a direct oncogenic effect was demonstrated. In particular, we showed that the expression of HIV-1 reverse transcriptase (RT) in 4T1 breast adenocarcinoma cells increases the tumorigenic and metastatic potential of cells in vitro and in vivo by a mechanism associated with the ability of RT to induce reactive oxygen species in cells (ROS). The aim of this work was to study the molecular mechanism of this process, namely the effect of HIV-1 RT on the key metabolic pathways associated with tumor progression: glycolysis and mitochondrial respiration. Expression of HIV-1 RT had no effect on the glycolysis process. At the same time, it led to an increase in mitochondrial respiration and the level of ATP synthesis in the cell, while not affecting the availability of the substrates, carbon donors for the Krebs cycle, which excludes the effect of RT on the metabolic enzymes of cells. Increased mitochondrial respiration was associated with restoration of the mitochondrial network despite the RT-induced reduction in mitochondrial mass. Increased mitochondrial respiration may increase cell motility, which explains their increased tumorigenicity and metastatic potential. These data are important for understanding the pathogenesis of HIV-1 infection, including the stimulation of the formation and spread of HIV-1 associated malignancies.

No evidence of bovine leukemia virus proviral DNA and antibodies in human specimens from Japan.

BACKGROUND: The potential risk and association of bovine leukemia virus (BLV) with human remains controversial as it has been reported to be both positive and negative in human breast cancer and blood samples. Therefore, establishing the presence of BLV in comprehensive human clinical samples in different geographical locations is essential. RESULT: In this study, we examined the presence of BLV proviral DNA in human blood and breast cancer tissue specimens from Japan. PCR analysis of BLV provirus in 97 Japanese human blood samples and 23 breast cancer tissues showed negative result for all samples tested using long-fragment PCR and highly-sensitive short-fragment PCR amplification. No IgG and IgM antibodies were detected in any of the 97 human serum samples using BLV gp51 and p24 indirect ELISA test. Western blot analysis also showed negative result for IgG and IgM antibodies in all tested human serum samples. CONCLUSION: Our results indicate that Japanese human specimens including 97 human blood, 23 breast cancer tissues, and 97 serum samples were negative for BLV.

Mouse Mammary Tumour Virus (MMTV) in Human Breast Cancer-The Value of Bradford Hill Criteria.

For many decades, the betaretrovirus, mouse mammary tumour virus (MMTV), has been a causal suspect for human breast cancer. In recent years, substantial new evidence has been developed. Based on this evidence, we hypothesise that MMTV has a causal role. We have used an extended version of the classic A. Bradford Hill causal criteria to assess the evidence. 1. Identification of MMTV in human breast cancers: The MMTV 9.9 kb genome in breast cancer cells has been identified. The MMTV genome in human breast cancer is up to 98% identical to MMTV in mice. 2. EPIDEMIOLOGY: The prevalence of MMTV positive human breast cancer is about 35 to 40% of breast cancers in Western countries and 15 to 20% in China and Japan. 3. Strength of the association between MMTV and human breast cancer: Consistency-MMTV env gene sequences are consistently five-fold higher in human breast cancer as compared to benign and normal breast controls. 4. Temporality (timing) of the association: MMTV has been identified in benign and normal breast tissues up to 10 years before the development of MMTV positive breast cancer in the same patient. 5. EXPOSURE: Exposure of humans to MMTV leads to development of MMTV positive human breast cancer. 6. Experimental evidence: MMTVs can infect human breast cells in culture; MMTV proteins are capable of malignantly transforming normal human breast epithelial cells; MMTV is a likely cause of biliary cirrhosis, which suggests a link between MMTV and the disease in humans. 7. Coherence-analogy: The life cycle and biology of MMTV in humans is almost the same as in experimental and feral mice. 8. MMTV Transmission: MMTV has been identified in human sputum and human milk. Cereals contaminated with mouse fecal material may transmit MMTV. These are potential means of transmission. 9. Biological plausibility: Retroviruses are the established cause of human cancers. Human T cell leukaemia virus type I (HTLV-1) causes adult T cell leukaemia, and human immunodeficiency virus infection (HIV) is associated with lymphoma and Kaposi sarcoma. 10. Oncogenic mechanisms: MMTV oncogenesis in humans probably differs from mice and may involve the enzyme APOBEC3B. CONCLUSION: In our view, the evidence is compelling that MMTV has a probable causal role in a subset of approximately 40% of human breast cancers.

Association between Epstein-Barr Virus Gene Polymorphism and Breast Cancer Risk among Egyptian Females.

BACKGROUND: Epstein-Barr virus (EBV) has been implicated in the development of breast cancer (BC) since 1995. It is classified into A/B genotypes, C/D subtypes, and F/f variants according to variations in its genome. AIM: To determine the distribution difference of EBV types between BC patients and healthy controls in Egypt and to detect the association between different EBV types and BC characteristics. METHODS: Three hundred and sixty-two participants (142 BC patients and 220 controls) were enrolled in this study. All participants were screened for EBV infection by determination of viral-capsid-IgG antibodies in their sera. EBNA-1 gene was detected by PCR in tumor biopsies of seropositive patients and in peripheral blood mononuclear cells of controls. A/B genotyping of EBV was performed by nested-PCR targeting the EBNA-2 gene. C/D subtypes and F/f variants were identified by Restriction fragment length polymorphism at BamHI-I W1/I1 and BamHI-F regions of EBV genome, respectively. RESULTS: Among 362 participants, 300(82.9%) were EBV-seropositive, including 120/142(84.5%) of the BC patients and 180/220(81.8 %) of the controls. EBNA-1 gene was positive in 54(45%) of seropositive BC patients and in 38(21.1%) of seropositive controls. There was a significant association of EBNA-1 gene with breast cancer (OR=3.05, 95%CI=1.84-5.07). Moreover, EBNA-1 gene positivity was significantly associated with the more aggressive tumors. Genotype-A and prototype-F were predominant among patients (90.4%, 100%, respectively) as well as among controls (91.7%, 100%, respectively) with no statistical significant association with BC risk.  However, subtype-D was significantly more frequent in patients (95.6%) than in controls (64.7%) and was significantly associated with a higher BC risk as compared to subtype-C (OR=11.7, 95%CI=2.4-57.08). Subtype-D was significantly associated with higher grades tumors (100% among grade III),  with progesteron receptor-negative tumors and with HER2-positive tumors (100% for each). The combined genotypes that significantly associated with BC risk were ADF (OR=4.9) and BDF (OR=5.5). CONCLUSIONS: Subtype-D of EBV could be the only EBV type implicated in BC development among Egyptian females and associated more with poor prognosis.

Systematic review and meta-analysis of the papillomavirus prevalence in breast cancer fresh tissues.

BACKGROUND: Although widely studied, the role of HPV in the genesis of breast carcinomas remains elusive due to the diversity of results across studies, possibly caused by the wide methodological heterogeneity, some of them with inadequate methods. OBJECTIVE: To verify the association between HPV and breast cancer through the meta-analysis of studies that used the best-recognized techniques for viral detection and tissue conservation. METHODS: A systematic review and meta-analysis restricted to studies that detected HPV by PCR in fresh and frozen tissue from breast cancer were conducted to obtain greater homogeneity. PubMed, Scopus, Science Direct, Cochrane Library, and SciELO were searched until December 14, 2019. Search terms included "breast cancer" and "HPV" without language restrictions. Eleven studies were included in the meta-analysis. The pooled relative risks and 95% confidence interval (95% CI) were calculated, and heterogeneity was assessed using the I-squared (I2). RESULTS: The selected studies had very low heterogeneity (2%). There is a 2.15 times higher combined relative risk (95% CI = 1.60-2.89) of detecting HPV in breast cancer than in cancer-free breast controls with a statistically significant p-value (p < 0.0001). CONCLUSION: Our data support the association of DNA-HPV with breast carcinomas. Further studies are needed to find out which breast cancer subtypes this association is most frequent.

Transcriptome analysis and connectivity mapping of Cissampelos pareira L. provides molecular links of ESR1 modulation to viral inhibition.

Bioactive fractions obtained from medicinal plants which have been used for the treatment of multiple diseases could exert their effects by targeting common pathways. Prior knowledge of their usage could allow us to identify novel molecular links. In this study, we explored the molecular basis of action of one such herbal formulation Cissampelos pareira L. (Cipa), used for the treatment of female hormone disorders and fever. Transcriptomic studies on MCF7 cell lines treated with Cipa extract carried out using Affymetrix arrays revealed a downregulation of signatures of estrogen response potentially modulated through estrogen receptor α (ERα). Molecular docking analysis identified 38 Cipa constituents that potentially bind (ΔG < - 7.5) with ERα at the same site as estrogen. The expression signatures in the connectivity map ( https://clue.io/; ) revealed high positive scores with translation inhibitors such as emetine (score: 99.61) and knockdown signatures of genes linked to the antiviral response such as ribosomal protein RPL7 (score: 99.92), which is a reported ERα coactivator. Further, gene knockdown experiments revealed that Cipa exhibits antiviral activity in dengue infected MCF7 cells potentially modulated through estrogen receptor 1. This approach reveals a novel pathway involving the ESR1-RPL7 axis which could be a potential target in dengue viral infection.

The management of a breast unit during the COVID-19 emergency: a local experience.

Introduction: Since breast imaging requires very close contact with patients, a protocol is needed to perform safe daily screening activities during the COVID-19 pandemic. Materials and methods: Patients were triaged and separated into three different clinical scenarios by performing a telephone questionnaire before each diagnostic exam or a nasopharyngeal swab before every recovery. Specific procedures for each scenario are described. Results: From July to October 2020, 994 exams were performed. A total of 16 cancers and 7 suspected COVID-19 patients were identified. No medical staff were infected. Conclusion: This protocol is an example of the practical use of guidelines applied to a breast unit to assist specialists in preventing COVID-19 infection and optimizing resources for breast cancer diagnosis.

Lay abstract On March 11th, 2020, the WHO officially declared the COVID-19 infection pandemic. Since breast cancer represents the most frequent cancer in women of all ages, and breast imaging examinations require very close contact with patients, a protocol was designed to optimize the management of patients and healthcare workers, performing strict COVID-19 screening and avoiding any impairment of survival of patients with breast cancer. Patients were separated into three different clinical scenarios (non-COVID-19 patients, suspected COVID-19 patients and confirmed COVID-19 patients) by performing a telephone questionnaire before each diagnostic exam or a nasopharyngeal swab before every recovery. Specific procedures for each scenario are described. Confirmed or suspected patients are rescheduled if not urgent. From July to October 2020, 994 exams were performed. A total of 16 cancers and 7 suspected COVID-19 patients were identified. No medical staff were infected. This study demonstrates efficacy in terms of continuity in the provision of an essential level of care in a breast cancer screening and ambulatory setting, providing an example of the practical use of guidelines applied to a breast unit, to assist specialists in preventing COVID-19 infection and optimizing resources for breast cancer diagnosis.

PDGFRα Enhanced Infection of Breast Cancer Cells with Human Cytomegalovirus but Infection of Fibroblasts Increased Prometastatic Inflammation Involving Lysophosphatidate Signaling.

Human cytomegalovirus (HCMV) infects 40-70% of adults in developed countries. HCMV proteins and DNA are detected in tumors and metastases, suggesting an association with increased invasion. We investigated HCMV infection in human breast cancer cell lines compared to fibroblasts, a component of tumors, and the role of platelet-derived growth factor receptor-α (PDGFRα). HCMV productively infected HEL299 fibroblasts and, to a lesser extent, Hs578T breast cancer cells. Infection of another triple-negative cell line, MDA-MB-231, and also MCF-7 cells, was extremely low. These disparate infection rates correlated with expression of PDGFRA, which facilitates HCMV uptake. Increasing PDGFRA expression in T-47D breast cancer and BCPAP thyroid cancer cells markedly increased HCMV infection. Conversely, HCMV infection decreased PDGFRA expression, potentially attenuating signaling through this receptor. HCMV infection of fibroblasts promoted the secretion of proinflammatory factors, whereas an overall decreased secretion of inflammatory factors was observed in infected Hs578T cells. We conclude that HCMV infection in tumors will preferentially target tumor-associated fibroblasts and breast cancer cells expressing PDGFRα. HCMV infection in the tumor microenvironment, rather than cancer cells, will increase the inflammatory milieu that could enhance metastasis involving lysophosphatidate.

Prognostic correlations with the microbiome of breast cancer subtypes.

Alterations to the natural microbiome are linked to different diseases, and the presence or absence of specific microbes is directly related to disease outcomes. We performed a comprehensive analysis with unique cohorts of the four subtypes of breast cancer (BC) characterized by their microbial signatures, using a pan-pathogen microarray strategy. The signature (includes viruses, bacteria, fungi, and parasites) of each tumor subtype was correlated with clinical data to identify microbes with prognostic potential. The subtypes of BC had specific viromes and microbiomes, with ER+ and TN tumors showing the most and least diverse microbiome, respectively. The specific microbial signatures allowed discrimination between different BC subtypes. Furthermore, we demonstrated correlations between the presence and absence of specific microbes in BC subtypes with the clinical outcomes. This study provides a comprehensive map of the oncobiome of BC subtypes, with insights into disease prognosis that can be critical for precision therapeutic intervention strategies.

Risk factor for breast cancer development under exposure to bovine leukemia virus in Colombian women: A case-control study.

Viruses have been implicated in cancer development in both humans and animals. The role of viruses in cancer is typically to initiate cellular transformation through cellular DNA damage, although specific mechanisms remain unknown. Silent and long-term viral infections need to be present, in order to initiate cancer disease. In efforts to establish a causative role of viruses, first is needed to demonstrate the strength and consistency of associations in different populations. The aim of this study was to determine the association of bovine leukemia virus (BLV), a causative agent of leukemia in cattle, with breast cancer and its biomarkers used as prognosis of the severity of the disease (Ki67, HER2, hormonal receptors) in Colombian women. An unmatched, observational case-control study was conducted among women undergoing breast surgery between 2016-2018. Malignant samples (n = 75) were considered as cases and benign samples (n = 83) as controls. Nested-liquid PCR, in-situ PCR and immunohistochemistry were used for viral detection in blood and breast tissues. For the risk assessment, only BLV positive samples from breast tissues were included in the analysis. BLV was higher in cases group (61.3%) compared with controls (48.2%), with a statistically significant association between the virus and breast cancer in the unconditional logistic regression (adjusted-OR = 2.450,95%CI:1.088-5.517, p = 0.031). In this study, BLV was found in both blood and breast tissues of participants and an association between breast cancer and the virus was confirmed in Colombia, as an intermediate risk factor.

The potential role of abnormal angiotensin-converting enzyme 2 expression correlated with immune infiltration after SARS-CoV-2 infection in the prognosis of breast cancer.

The potential role of abnormal ACE2 expression after SARS-CoV-2 infection in the prognosis of breast cancer is still ambiguous. In this study, we analyzed ACE2 changes in breast cancer and studied the correlation between ACE2 and the prognosis and further analyzed the relationship between immune infiltration and the prognosis of different breast cancer subtypes. Finally, we inferred the prognosis of breast cancer patients after SARS-CoV-2 infection. We found that ACE2 expression decreased significantly in breast cancer, except for basal-like subtype. Decreased ACE2 expression level was correlated with abnormal immune infiltration and poorer prognosis of luminal B breast cancer (RFS: HR 0.76, 95%CI=0.63-0.92, p=0.005; DMFS: HR 0.70, 95%CI=0.49-1.00, p=0.046). The expression of ACE2 was strongly positively correlated with the immune infiltration level of CD8+ T cell (r=0.184, p<0.001), CD4+ T cell (r=0.104, p=0.02) and neutrophils (r=0.101, p=0.02). ACE2 expression level in the luminal subtype was positively correlated with CD8A and CD8B markers in CD8+ T cells, and CEACAM3, S100A12 in neutrophils. In conclusion, breast tumor tissues might undergo a further decrease in the expression level of ACE2 after SARS-CoV-2 infection, which could contribute to further deterioration of immune infiltration and worsen the prognosis of luminal B breast cancer after SARS-CoV-2 infection.

Human papillomavirus in breast cancer of patients with cervical intraepithelial neoplasia or cervical cancer history. A systematic review and meta-analysis.

PURPOSE: Many cohort studies and meta-analyses support the oncogenic role of the human papilloma virus (HPV) on breast tissue. However, only a few studies examine the association between HPV-positive breast cancer and the prior history of high grade cervical intraepithelial neoplasia (CIN) or cervical cancer. The present systematic review and meta-analysis aimed to determine whether women with a history of high grade CIN or cervical cancer are at a higher risk of developing HPV-positive breast cancer. METHODS: MEDLINE, CENTRAL and Scopus databases as well as "gray literature" sources were searched for case-control studies, detecting and genotyping HPV genome in breast cancer patients with and without a history of CIN or cervical cancer, from inception to October 23, 2020. RESULTS: The meta-analysis included three case-control studies with 265 breast cancer patients in total. HPV related breast cancer was associated with a history of high grade CIN or cervical cancer [pooled odds ratio (OR) =7.98, 95% confidence interval (CI), 1.84 to 34.67]. This association remained regarding HPV-16 related breast cancer (pooled OR =7.60, 95% CI, 1.75 to 33.00). CONCLUSIONS: HPV was detected more frequently in breast cancer patients with CIN or cervical cancer history. Therefore, further research is necessary to understand better the HPV transmission route to the breast.

Impact of the COVID-19 Pandemic on Breast Cancer Mortality in the US: Estimates From Collaborative Simulation Modeling.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has disrupted breast cancer control through short-term declines in screening and delays in diagnosis and treatments. We projected the impact of COVID-19 on future breast cancer mortality between 2020 and 2030. METHODS: Three established Cancer Intervention and Surveillance Modeling Network breast cancer models modeled reductions in mammography screening use, delays in symptomatic cancer diagnosis, and reduced use of chemotherapy for women with early-stage disease for the first 6 months of the pandemic with return to prepandemic patterns after that time. Sensitivity analyses were performed to determine the effect of key model parameters, including the duration of the pandemic impact. RESULTS: By 2030, the models project 950 (model range = 860-1297) cumulative excess breast cancer deaths related to reduced screening, 1314 (model range = 266-1325) associated with delayed diagnosis of symptomatic cases, and 151 (model range = 146-207) associated with reduced chemotherapy use in women with hormone positive, early-stage cancer. Jointly, 2487 (model range = 1713-2575) excess breast cancer deaths were estimated, representing a 0.52% (model range = 0.36%-0.56%) cumulative increase over breast cancer deaths expected by 2030 in the absence of the pandemic's disruptions. Sensitivity analyses indicated that the breast cancer mortality impact would be approximately double if the modeled pandemic effects on screening, symptomatic diagnosis, and chemotherapy extended for 12 months. CONCLUSIONS: Initial pandemic-related disruptions in breast cancer care will have a small long-term cumulative impact on breast cancer mortality. Continued efforts to ensure prompt return to screening and minimize delays in evaluation of symptomatic women can largely mitigate the effects of the initial pandemic-associated disruptions.

Molecular and Serological Prevalence of HCMV in Iranian Patients with Breast Cancer.

BACKGROUND: Human cytomegalovirus (HCMV) is prevalent viral infection involved in several human cancers including breast cancer. The presence of HCMV genome in breast cancer tissue and footprint of viral last exposure patient's serum are considered as important factor in the process of breast cancer development. OBJECTIVES: This study aimed to investigate molecular and serological epidemiology of HCMV in patients with breast cancer in Iran for first time. METHODS: In our case-control study, 98 samples of breast tissue, including 49 cancerous (case) and 49 adjacent non-cancerous tissue were collected (control). In addition, we collected sera samples from all patients (n=49) and healthy individual (n=49). Seroprevalence of HCMV was assessed by Enzyme-linked immunosorbent assay (ELISA) and detection of HCMV genome was performed using Nested-PCR method. RESULTS: HCMV genome found in 16.3% (8/49) of cases tissue and 2% (1/49) of controls tissue. In patients group, the levels of anti-CMV IgG and IgM were 93.9% and 2% compared to 69.4% and 4.1% in healthy individuals, respectively. There was a statistically difference between the anti-CMV IgG in patients and healthy control (p= 0.002). We found 75% of (6/8) HCMV genome positive PCR samples were also positive for their anti-CMV IgG in cases which was statistically significant (p= 0.01).  Conclusions: Our result showed significant presence of HCMV genome and anti-CMV IgG in patients, supporting the role of HCMV in breast cancer.
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Effects of Epstein-Barr Virus Infection on the Response of Human Breast Cancer Cells to Nicotine.

BACKGROUND/AIM: The purpose of our study was to test whether EBV infection affects the response of human breast cancer cells to nicotine. In addition, the underlying signaling mechanisms were evaluated. MATERIALS AND METHODS: EBV-infected MDA-MB-231 and LMP1-transfected MDA-MB-231 breast cancer cells were established. Reverse transcription-polymerase chain reaction and western blotting were performed to evaluate nicotine receptor expression. To verify the functional role and underlying signaling mechanism of nicotine receptor expression induced by EBV infection, morphologic analysis, and proliferation and inhibition assays were performed. RESULTS: Both EBV infection and LMP1 transfection increased cell proliferation and induced the up-regulation of α9-nAChR expression. Additionally, nicotine treatment induced tumorigenic activity in both EBV-infected and LMP1-transfected MDA-MB-231 breast cancer cells. Western blot and inhibitor assays showed that the nicotine-induced signaling was mediated through MAPK/ERK and AKT signaling pathways in EBV-infected and LMP1-transfected breast cancer cells, respectively. CONCLUSION: These results suggest that EBV infection and EBV-related LMP1 may act as potential molecular targets for breast cancer risk associated with nicotine, and provide a novel insight into the mechanism of nicotine stimulation in EBV-positive breast cancer cells.

Loneliness and mental health during the COVID-19 pandemic in older breast cancer survivors and noncancer controls.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has had wide-ranging health effects and increased isolation. Older with cancer patients might be especially vulnerable to loneliness and poor mental health during the pandemic. METHODS: The authors included active participants enrolled in the longitudinal Thinking and Living With Cancer study of nonmetastatic breast cancer survivors aged 60 to 89 years (n = 262) and matched controls (n = 165) from 5 US regions. Participants completed questionnaires at parent study enrollment and then annually, including a web-based or telephone COVID-19 survey, between May 27 and September 11, 2020. Mixed-effects models were used to examine changes in loneliness (a single item on the Center for Epidemiologic Studies-Depression [CES-D] scale) from before to during the pandemic in survivors versus controls and to test survivor-control differences in the associations between changes in loneliness and changes in mental health, including depression (CES-D, excluding the loneliness item), anxiety (the State-Trait Anxiety Inventory), and perceived stress (the Perceived Stress Scale). Models were adjusted for age, race, county COVID-19 death rates, and time between assessments. RESULTS: Loneliness increased from before to during the pandemic (0.211; P = .001), with no survivor-control differences. Increased loneliness was associated with worsening depression (3.958; P < .001) and anxiety (3.242; P < .001) symptoms and higher stress (1.172; P < .001) during the pandemic, also with no survivor-control differences. CONCLUSIONS: Cancer survivors reported changes in loneliness and mental health similar to those reported by women without cancer. However, both groups reported increased loneliness from before to during the pandemic that was related to worsening mental health, suggesting that screening for loneliness during medical care interactions will be important for identifying all older women at risk for adverse mental health effects of the pandemic.