High prevalence of human cytomegalovirus proteins and nucleic acids in primary breast cancer and metastatic sentinel lymph nodes

Human Cytomegalovirus Infection and Breast Cancer: A Literature Review of Clinical and Experimental Data

Breast cancer (BC) remains a significant global health challenge, highlighting the need for continued research into novel risk factors, diagnostic approaches, and personalized treatments. Among emerging risk factors, viral infections have been implicated as potential contributors to breast carcinogenesis and BC progression. Recent evidence suggests that specific oncogenic strains of human cytomegalovirus (HCMV) may have the capacity to transform human mammary epithelial cells. This review assesses clinical data regarding HCMV presence in both tumor and non-tumor breast tissues, examining the role of HCMV oncoproteins in BC development and progression. Current findings indicate a higher prevalence of HCMV infection in breast carcinomas compared to non-tumor tissues, associated with an elevated risk of BC. Additionally, the HCMV-driven breast carcinogenesis model proposed here suggests that HCMV oncoproteins may activate multiple oncogenic pathways, fostering cell proliferation, survival, and tumor development. A deeper understanding of the role of HCMV in BC could enhance risk stratification and support the creation of targeted therapeutic strategies.

Enhanced levels of IL-6 and PAI-1 and decreased levels of MMP-3 in cytomegalovirus seropositive patients with prior myocardial infarction

Background

Efforts to understand atherosclerosis, a major cause of ischemic heart disease, have linked several lifestyle factors to increased risk for developing cardiovascular disease. Some studies suggest that cytomegalovirus (CMV), a widely prevalent herpesvirus, is reactivated in atherosclerotic plaques and associated with higher cardiovascular mortality risk. We aimed to explore whether CMV seropositivity and CMV-IgG antibody levels correlate with relevant biomarkers in a cohort of patients with myocardial infarction (MI) and matched controls.

Methods and results

We analyzed a dataset from 324 survivors of MI treated in Stockholm between 1996 and 2001. Blood samples collected three months after MI were used to measure protective Apo B100 autoantibodies, metabolic, and inflammatory biomarkers. CMV serology was performed on stored serum samples. Correlation analyses were conducted between biomarkers and CMV serostatus in 324 patients and age- and sex-matched controls. While CMV seroprevalence was equal, the CMV-IgG levels were higher in controls. Among various factors examined, CMV seropositive MI patients had elevated levels of plasminogen activator inhibitor-1 (PAI-1) and interleukin-6, along with lower levels of MMP-3, than CMV seronegative MI patients. CMV-IgG levels correlated positively with PAI-1 levels in patients. Although CMV seropositivity was associated with increased proinsulin levels, there was no correlation with diabetes diagnosis.

Conclusions

Our findings suggest an enhanced inflammatory and prothrombotic state in CMV seropositive patients after MI. Notably, patients had lower levels of CMV IgG than controls.

Cytokine levels in breast cancer are highly dependent on cytomegalovirus (CMV) status

PURPOSE

Breast cancer accounts for 30% of all female cancers in the US. Cytomegalovirus (CMV), a herpesvirus that establishes lifelong infection, may play a role in breast cancer. CMV is not oncogenic, yet viral DNA and proteins have been detected in breast tumors, indicating possible contribution to tumor development. CMV encodes cmvIL-10, a homolog of human cellular IL-10 (cIL-10) with potent immunosuppressive activities. We investigated the relationship between CMV infection, cytokines, and breast cancer.

METHODS

We evaluated CMV serostatus and cytokine levels in plasma of women with benign breast disease (n = 38), in situ carcinoma (n = 41), invasive carcinoma, no lymph node involvement (Inv/LN-; n = 41), and invasive with lymph node involvement (Inv/LN+; n = 37).

RESULTS

Fifty percent of the patient samples (n = 79) were CMV seropositive. There was no correlation between CMV status and diagnosis (p = 0.75). For CMV+ patients, there was a trend toward higher CMV IgG levels in invasive disease (p = 0.172). CmvIL-10 levels were higher in CMV+ in situ patients compared to the Inv/LN- and Inv/LN+ groups (p = 0.020). Similarly, cIL-10 levels were higher in CMV+ in situ patients compared to the Inv/LN- and Inv/LN+ groups (p = 0.043). The results were quite different in CMV- patients where cIL-10 levels were highest in Inv/LN- compared to benign, in situ, or Inv/LN+ (p = 0.019). African American patients were significantly associated with CMV+ status (p = 0.001) and had lower cmvIL-10 levels than Caucasian patients (p = 0.046).

CONCLUSION

No association was observed between CMV IgG and diagnosis, but CMV infection influences cytokine production and contributes to altered cytokine profiles in breast cancer.

The association between infectious agents and breast cancer: a review of the epidemiologic evidence

PURPOSE

Several viruses have been casually linked to human cancers, including cervical, nasopharyngeal, liver, sarcoma, and Merkel cell carcinomas. However, the etiologic contribution of viral infections to breast cancer, the number one incident cancer among women worldwide, is not well established. Among studies exploring associations of viruses with breast cancer, potential linkages have been identified between breast cancer and five viruses: beta retrovirus, (i.e., mouse mammary tumor virus), human papillomavirus, Epstein Barr virus. bovine leukemia virus, and human cytomegalovirus.

METHODS

In this review, we provide a comprehensive evaluation of epidemiological ecologic, case-control, case-only, and cohort studies investigating these associations. We discuss results from several existing reviews and meta-analyses, evaluate epidemiological studies published in the past five years, and assess the relationship between these viruses and breast tumor clinicopathological factors.

RESULTS

The strongest epidemiological evidence for a viral role in breast cancer exists for MMTV and HPV, though limitations include lack of prospective studies for MMTV and potential detection bias in HPV studies. Viral detection challenges have limited studies of EBV and HCMV. Fewer studies have evaluated BLV, and though it has been associated with higher risk of breast cancer, sample sizes are quite small.   CONCLUSION: While epidemiologic evidence exists for an association between these five viruses and breast cancer, various methodological issues and lack of prospective studies preclude robust conclusions. Future research should prioritize establishing a temporal relationship between infection and disease, minimizing misclassification of detection assays, and further exploring the influence of co-infections.

Polyploid Giant Cancer Cells: A Distinctive Feature in the Transformation of Epithelial Cells by High-Risk Oncogenic HCMV Strains

Human cytomegalovirus (HCMV) infection is common in tumor tissues across different types of cancer. While HCMV has not been recognized as a cancer-causing virus, numerous studies hint at its potential role in cancer development where its presence in various cancers corresponds with the hallmarks of cancer. Herein, we discuss and demonstrate that high-risk HCMV-DB and BL strains have the potential to trigger transformation in epithelial cells, including human mammary epithelial cells (HMECs), ovarian epithelial cells (OECs), and prostate epithelial cells (PECs), through the generation of polyploid giant cancer cells (PGCCs). A discussion is provided on how HCMV infection creates a cellular environment that promotes oncogenesis, supporting the continuous growth of CMV-transformed cells. The aforementioned transformed cells, named CTH, CTO, and CTP cells, underwent giant cell cycling with PGCC generation parallel to dedifferentiation, displaying stem-like characteristics and an epithelial-mesenchymal transition (EMT) phenotype. Furthermore, we propose that giant cell cycling through PGCCs, increased EZH2 expression, EMT, and the acquisition of malignant traits represent a deleterious response to the cellular stress induced by high-risk oncogenic HCMV strains, the latter being the origin of the transformation process in epithelial cells upon HCMV infection and leading to adenocarcinoma of poor prognosis.

Friend or Foe? Exploring the Role of Cytomegalovirus (HCMV) Infection in Head and Neck Tumors

Although not regarded as an oncogenic pathogen, the human cytomegalovirus (HCMV) has been associated with a wide array of malignancies. Conversely, a number of studies report on possible anti-tumor properties of the virus, apparently mediated via HCMV-galvanized T-cell tumor killing; these were recently being investigated in clinical trials for the purposes of anti-cancer treatment by means of dendritic cell vaccines and HCMV-specific cytotoxic T cells. In the present study, we have analyzed the relation between a complement of head-and-neck tumors and HCMV infection across 73 countries worldwide using Spearman correlation, univariate and multivariate regression analysis. Intriguingly, HCMV was found to be pro-oncogenic in patients with nasopharyngeal carcinoma; contrarywise, the virus manifested an inverse (i.e., anti-tumor) association with the tumors of the lip/oral region and the salivary glands. Although this putative protective effect was noted initially for thyroid neoplasia and hypopharyngeal tumors as well, after multivariate regression analysis the connection did not hold. There was no association between laryngeal cancer and HCMV infection. It would appear that, depending on the tissue, HCMV may exert both protective and oncogenic effects. The globally observed protective feature of the virus could potentially be utilized in future therapeutic approaches for salivary tumors and neoplasia in the lip/oral region. As correlation does not necessarily imply causation, more in-depth molecular analyses from comprehensive clinical studies are warranted to substantiate our findings.

Human Cytomegalovirus Oncoprotection across Diverse Populations, Tumor Histologies, and Age Groups: The Relevance for Prospective Vaccinal Therapy

The oncogenicity of the human cytomegalovirus (CMV) is currently being widely debated. Most recently, mounting clinical evidence suggests an anti-cancer effect via CMV-induced T cell-mediated tumor destruction. However, the data were mostly obtained from single-center studies and in vitro experiments. Broad geographic coverage is required to offer a global perspective. Our study examined the correlation between country-specific CMV seroprevalence (across 73 countries) and the age-standardized incidence rate (of 34 invasive tumors). The populations studied were stratified according to decadal age periods as the immunologic effects of CMV seropositivity may depend upon age at initial infection. The International Agency for Research on Cancer of the World Health Organization (IARC WHO) database was used. The multivariate linear regression analysis revealed a worldwide inverse correlation between CMV seroprevalence and the incidences of 62.8% tumors. Notably, this inverse link persists for all cancers combined (Spearman's ρ = -0.732, p < 0.001; β = -0.482, p < 0.001, adjusted R2 = 0.737). An antithetical and significant correlation was also observed in particular age groups for the vast majority of tumors. Our results corroborate the conclusions of previous studies and indicate that this oncopreventive phenomenon holds true on a global scale. It applies to a wide spectrum of cancer histologies, additionally supporting the idea of a common underlying mechanism-CMV-stimulated T cell tumor targeting. Although these results further advance the notion of CMV-based therapies, in-depth investigation of host-virus interactions is still warranted.

Targeting Breast Cancer with N-Acetyl-D-Glucosamine: Integrating Machine Learning and Cellular Assays for Promising Results

BACKGROUND

Breast cancer is a common cancer with high mortality rates. Early diagnosis is crucial for reducing the prognosis and mortality rates. Therefore, the development of alternative treatment options is necessary.

OBJECTIVE

This study aimed to investigate the inhibitory effect of N-acetyl-D-glucosamine (D-GlcNAc) on breast cancer using a machine learning method. The findings were further confirmed through assays on breast cancer cell lines.

METHODS

MCF-7 and 4T1 cell lines (ATCC) were cultured in the presence and absence of varying concentrations of D-GlcNAc (0.5 mM, 1 mM, 2 mM, and 4 mM) for 72 hours. A xenograft mouse model for breast cancer was established by injecting 4T1 cells into mammary glands. D-GlcNAc (2 mM) was administered intraperitoneally to mice daily for 28 days, and histopathological effects were evaluated at pre-tumoral and post-tumoral stages.

RESULTS

Treatment with 2 mM and 4 mM D-GlcNAc significantly decreased cell proliferation rates in MCF-7 and 4T1 cell lines and increased Fas expression. The number of apoptotic cells was significantly higher than untreated cell cultures (p < 0.01 - p < 0.0001). D-GlcNAc administration also considerably reduced tumour size, mitosis, and angiogenesis in the post-treatment group compared to the control breast cancer group (p < 0.01 - p < 0.0001). Additionally, molecular docking/dynamic analysis revealed a high binding affinity of D-GlcNAc to the marker protein HER2, which is involved in tumour progression and cell signalling.

CONCLUSION

Our study demonstrated the positive effect of D-GlcNAc administration on breast cancer cells, leading to increased apoptosis and Fas expression in the malignant phenotype. The binding affinity of D-GlcNAc to HER2 suggests a potential mechanism of action. These findings contribute to understanding D-GlcNAc as a potential anti-tumour agent for breast cancer treatment.

A virally encoded GPCR drives glioblastoma through feed-forward activation of the SK1-S1P1 signaling axis

The G protein-coupled receptor (GPCR) US28 encoded by the human cytomegalovirus (HCMV) is associated with accelerated progression of glioblastomas, aggressive brain tumors with a generally poor prognosis. Here, we showed that US28 increased the malignancy of U251 glioblastoma cells by enhancing signaling mediated by sphingosine-1-phosphate (S1P), a bioactive lipid that stimulates oncogenic pathways in glioblastoma. US28 expression increased the abundance of the key components of the S1P signaling axis, including an enzyme that generates S1P [sphingosine kinase 1 (SK1)], an S1P receptor [S1P receptor 1 (S1P1)], and S1P itself. Enhanced S1P signaling promoted glioblastoma cell proliferation and survival by activating the kinases AKT and CHK1 and the transcriptional regulators cMYC and STAT3 and by increasing the abundance of cancerous inhibitor of PP2A (CIP2A), driving several feed-forward signaling loops. Inhibition of S1P signaling abrogated the proliferative and anti-apoptotic effects of US28. US28 also activated the S1P signaling axis in HCMV-infected cells. This study uncovers central roles for S1P and CIP2A in feed-forward signaling that contributes to the US28-mediated exacerbation of glioblastoma.

Detection of Human cytomegalovirus UL55 Gene and IE/E Protein Expression in Colorectal Cancer Patients in Egypt

BACKGROUND

A possible relation between Human cytomegalovirus (HCMV) and colorectal cancer (CRC) has been widely explored with an unclear role yet speculated.

AIM

The study aimed at detecting HCMV UL55 gene, immediate early and early (IE/E) proteins in colorectal tumor tissues and adjacent non neoplastic tissues (ANNT). Also, it aimed to correlate HCMV presence with CRC clinicopathological features.

SUBJECTS AND METHODS

A prospective study of 50 HCMV seropositive patients with resectable CRC were enrolled in the study. Demographic, clinical, and radiological findings were recorded. Pathological assessment was done. Paired CRC tumorous and ANNT were examined for HCMV UL55 by PCR and for IE/ E proteins by immunohistochemistry (IHC).

RESULTS

70% of CRC patients enrolled were females and 36% were elderly (> 60y). Adenocarcinoma was the prevalent histopathological type (92%) with Grade 2, higher stages, and nodal involvement accounting for (64%, 64% and 56%) respectively. HCMV detection was significantly higher in tumoral tissue versus ANNT by PCR and IHC (P < 0.001, P < 0.008) respectively. Moderate agreement was found between the two techniques (κ = 0.572, P < 0.001). Univariate analysis identified HCMV presence to be significantly higher in elderly patients, in tumors with higher stage and with nodal involvement (P = 0.041, P = 0.008, P = 0.018 respectively). In multivariate analysis, the latter two retained significance (P = 0.010, P = 0.008).

CONCLUSION

CRC tumor tissues are more infected by HCMV than ANNT. A significant association of HCMV presence with a higher CRC tumor stage and nodal involvement in an age-dependent manner was detected. HCMV oncomodulatory and a disease progression role is suspected.

Applications of Anti-Cytomegalovirus T Cells for Cancer (Immuno)Therapy

Infection with cytomegalovirus (CMV) is highly prevalent in the general population and largely controlled by CD8pos T cells. Intriguingly, anti-CMV T cells accumulate over time to extraordinarily high numbers, are frequently present as tumor-resident 'bystander' T cells, and remain functional in cancer patients. Consequently, various strategies for redirecting anti-CMV CD8pos T cells to eliminate cancer cells are currently being developed. Here, we provide an overview of these strategies including immunogenic CMV peptide-loading onto endogenous HLA complexes on cancer cells and the use of tumor-directed fusion proteins containing a preassembled CMV peptide/HLA-I complex. Additionally, we discuss conveying the advantageous characteristics of anti-CMV T cells in adoptive cell therapy. Utilization of anti-CMV CD8pos T cells to generate CAR T cells promotes their in vivo persistence and expansion due to appropriate co-stimulation through the endogenous (CMV-)TCR signaling complex. Designing TCR-engineered T cells is more challenging, as the artificial and endogenous TCR compete for expression. Moreover, the use of expanded/reactivated anti-CMV T cells to target CMV peptide-expressing glioblastomas is discussed. This review highlights the most important findings and compares the benefits, disadvantages, and challenges of each strategy. Finally, we discuss how anti-CMV T cell therapies can be further improved to enhance treatment efficacy.

Polyploid giant cancer cells, cytokines and cytomegalovirus in breast cancer progression

BACKGROUND

Breast cancer is the most common cancer among women. Accumulated evidence over the past decades indicates a very high prevalence of human cytomegalovirus (HCMV) in breast cancer. High-risk HCMV strains possess a direct oncogenic effect displayed by cellular stress, polyploid giant cancer cells (PGCCs) generation, stemness, and epithelial-to-mesenchymal transition (EMT) leading to cancer of aggressive phenotype. Breast cancer development and progression have been regulated by several cytokines where the latter can promote cancer cell survival, help in tumor immune evasion, and initiate the EMT process, thereby resulting in invasion, angiogenesis, and breast cancer metastasis. In the present study, we screened cytokines expression in cytomegalovirus-transformed HMECs (CTH cells) cultures infected with HCMV high-risk strains namely, HCMV-DB and BL, as well as breast cancer biopsies, and analyzed the association between cytokines production, PGCCs count, and HCMV presence in vitro and in vivo.

METHODS

In CTH cultures and breast cancer biopsies, HCMV load was quantified by real-time qPCR. PGCCs count in CTH cultures and breast cancer biopsies was identified based on cell morphology and hematoxylin and eosin staining, respectively. CTH supernatants were evaluated for the production of TGF-β, IL-6, IL1-β, and IL-10 by ELISA assays. The above-mentioned cytokines expression was assessed in breast cancer biopsies using reverse transcription-qPCR. The correlation analyses were performed using Pearson correlation test.

RESULTS

The revealed PGCCs/cytokine profile in our in vitro CTH model matched that of the breast cancer biopsies, in vivo. Pronounced cytokine expression and PGCCs count were detected in particularly CTH-DB cultures and basal-like breast cancer biopsies.

CONCLUSIONS

The analysis of cytokine profiles in PGCCs present mostly in basal-like breast cancer biopsies and derived from CTH cells chronically infected with the high-risk HCMV strains might have the potential to provide novel therapies such as cytokine-based immunotherapy which is a promising field in cancer treatments.

Human Cytomegalovirus Protein Expression Is Correlated with Shorter Overall Survival in Breast Cancer Patients: A Cohort Study

Background: Human cytomegalovirus (HCMV) is increasingly suggested to be involved in human carcinogenesis and onco-modulation due to its ability to contribute to all hallmarks of cancer. Growing evidence demonstrates a link between HCMV infection and various malignancies, including breast cancer, which incidence and mortality are still on the rise. The etiology of breast cancer remains mostly unclear, leaving 80% of breast cancer cases considered to be sporadic. Identifying novel risk- and prognostic factors for improved breast cancer treatment and increased survival rates, were the objectives of this study. Methods: Automated immunohistochemical staining results for HCMV proteins in 109 breast tumors and lymph node metastasis were correlated with clinical follow-up data (>10 years). Statistical analyses for median Overall Survival (OS) were performed. Results: Survival analyses revealed shorter median OS for patients with HCMV-IE positive tumors of 118.4 months compared to 202.4 months for HCMV-IE negative tumors. A higher number of HCMV-LA positive cells in the tumors was also associated with a shorter OS in patients (146.2 months vs. 151.5 months). Conclusions: Our findings suggest a link between HCMV-infections and breast cancer prognosis, which paves the way for potential novel clinical intervention and targeted therapy that may prolong the overall survival of selected patients with breast cancer.

The Journey of Cancer Cells to the Brain: Challenges and Opportunities

Cancer metastases into the brain constitute one of the most severe, but not uncommon, manifestations of cancer progression. Several factors control how cancer cells interact with the brain to establish metastasis. These factors include mediators of signaling pathways participating in migration, infiltration of the blood-brain barrier, interaction with host cells (e.g., neurons, astrocytes), and the immune system. Development of novel therapies offers a glimpse of hope for increasing the diminutive life expectancy currently forecasted for patients suffering from brain metastasis. However, applying these treatment strategies has not been sufficiently effective. Therefore, there is a need for a better understanding of the metastasis process to uncover novel therapeutic targets. In this review, we follow the journey of various cancer cells from their primary location through the diverse processes that they undergo to colonize the brain. These processes include EMT, intravasation, extravasation, and infiltration of the blood-brain barrier, ending up with colonization and angiogenesis. In each phase, we focus on the pathways engaging molecules that potentially could be drug target candidates.

Prognosis of Human Cytomegalovirus in Cancer Patients Undergoing Chemotherapeutic Treatment in Egypt and an Emergent Prevalence of Glycoprotein B-5

The human cytomegalovirus (HCMV) is a global opportunistic β-herpes virus causing severe diseases in immune-compromised patients, such as malignant tumor patients, especially those undergoing chemotherapeutic treatment. This study aimed to determine the prevalence of HCMV-DNA in chemotherapeutic treatment naive cancer patients, and after chemotherapy, to compare between conventional nested PCR and ELISA techniques for the detection of HCMV, and to detect glycoprotein B genotypes. Plasma and serum samples before and after three chemotherapy cycles were collected from 49 chemotherapy-naive cancer patients. DNA was extracted from plasma samples using QIAamp® DNA Mini kit. HCMV-DNA was detected using a nested PCR technique. Multiplex nested PCR was used for HCMV-glycoprotein B (gB) genotyping. HCMV-IgG and -IgM were detected using ELISA technique. Thirty one (63.3 %) of the 49 plasma samples of the chemotherapy-naïve cancer patients were positive for HCMV-DNA; 21 of which remained positive after chemotherapy. However, 18 samples were negative of which 16 became positive after chemotherapy. gB-5 was the most common glycoprotein genotype detected (80.6 %), followed by gB-1, gB-3, gB-4, and gB-2. HCMV IgG was detected in the 49 serum samples of chemotherapy-naïve patients, and after exposure to chemotherapy. HCMV-DNA is commonly identified in cancer patients. Its detection after chemotherapy exposure may suggest HCMV reactivation. The most common genotype detected in cancer patients in Egypt is gB-5 in contrast to earlier research. IgG was detected in all patients. This indicates that HCMV is endemic in Egypt, necessitating the development of public awareness campaigns about HCMV infection and preventive strategies.

Mechanisms of Survival of Cytomegalovirus-Infected Tumor Cells

Human cytomegalovirus (HCMV) DNA and proteins are often detected in malignant tumors, warranting studies of the role that HCMV plays in carcinogenesis and tumor progression. HCMV proteins were shown to regulate the key processes involved in tumorigenesis. While HCMV as an oncogenic factor just came into focus, its ability to promote tumor progression is generally recognized. The review discusses the viral factors and cell molecular pathways that affect the resistance of cancer cells to therapy. CMV inhibits apoptosis of tumor cells, that not only promotes tumor progression, but also reduces the sensitivity of cells to antitumor therapy. Autophagy was found to facilitate either cell survival or cell death in different tumor cells. In leukemia cells, HCMV induces a "protective" autophagy that suppresses apoptosis. Viral factors that mediate drug resistance and their interactions with key cell death pathways are necessary to further investigate in order to develop agents that can restore the tumor sensitivity to anticancer drugs.

Inflammatory Breast Cancer: The Secretome of HCMV+ Tumor-Associated Macrophages Enhances Proliferation, Invasion, Colony Formation, and Expression of Cancer Stem Cell Markers

Inflammatory breast cancer (IBC) is a highly aggressive phenotype of breast cancer that is characterized by a high incidence early metastasis. We previously reported a significant association of human cytomegalovirus (HCMV) DNA in the carcinoma tissues of IBC patients but not in the adjacent normal tissues. HCMV-infected macrophages serve as “mobile vectors” for spreading and disseminating virus to different organs, and IBC cancer tissues are highly infiltrated by tumor-associated macrophages (TAMs) that enhance IBC progression and promote breast cancer stem cell (BCSC)-like properties. Therefore, there is a need to understand the role of HCMV-infected TAMs in IBC progression. The present study aimed to test the effect of the secretome (cytokines and secreted factors) of TAMs derived from HCMV⁺ monocytes isolated from IBC specimens on the proliferation, invasion, and BCSC abundance when tested on the IBC cell line SUM149. HCMV⁺ monocytes were isolated from IBC patients during modified radical mastectomy surgery and tested in vitro for polarization into TAMs using the secretome of SUM149 cells. MTT, clonogenic, invasion, real-time PCR arrays, PathScan Intracellular Signaling array, and cytokine arrays were used to characterize the secretome of HCMV⁺ TAMs for their effect on the progression of SUM149 cells. The results showed that the secretome of HCMV⁺ TAMs expressed high levels of IL-6, IL-8, and MCP-1 cytokines compared to HCMV^- TAMs. In addition, the secretome of HCMV⁺ TAMs induced the proliferation, invasion, colony formation, and expression of BCSC-related genes in SUM149 cells compared to mock untreated cells. In addition, the secretome of HCMV⁺ TAMs activated the phosphorylation of intracellular signaling molecules p-STAT3, p-AMPKα, p-PRAS40, and p-SAPK/JNK in SUM149 cells. In conclusion, this study shows that the secretome of HCMV⁺ TAMs enhances the proliferation, invasion, colony formation, and BCSC properties by activating the phosphorylation of p-STAT3, p-AMPKα, p-PRAS40, and p-SAPK/JNK intracellular signaling molecules in IBC cells.

Human cytomegalovirus alters immune cell profile with potential implications for patient survival in head and neck cancer

Cytomegalovirus (CMV) is a highly prevalent human herpes virus that exerts a strong influence on immune repertoire which may influence cancer risk. We have tested whether CMV immunoglobulin G (IgG) serostatus is associated with immune cell proportions (n = 132 population controls), human papillomavirus (HPV) co-infection and head and neck cancer risk (n = 184 cancer cases and 188 controls) and patient survival. CMV status was not associated with the proportion of Natural Killer cells, B cells or the neutrophil-to-lymphocyte ratio. However, CD8+ T cells increased with increasing categories of IgG titers (P =1.7 × 10-10), and titers were inversely associated with the CD4:CD8 ratio (P = 5.6 × 10-5). Despite these differences in T cell proportions, CMV was not associated with HPV16 co-infection. CMV seropositivity was similar in cases (52%) and controls (47%) and was not associated with patient survival (hazard ratio [HR] 1.14, 95% confidence interval [CI]: 0.70 to 1.86). However, those patients with the highest titers had the worst survival (HR 1.91, 95% CI: 1.13 to 3.23). Tumor-based data from The Cancer Genome Atlas demonstrated that the presence of CMV transcripts was associated with worse patient survival (HR 1.79, 95% CI: 0.96 to 2.78). These findings confirm that a history of CMV infection alters T cell proportions, but this does not translate to HPV16 co-infection or head and neck cancer risk. Our data suggest that high titers and active CMV virus in the tumor environment may confer worse survival.

Polyploid giant cancer cells, EZH2 and Myc upregulation in mammary epithelial cells infected with high-risk human cytomegalovirus

Background

Human cytomegalovirus (HCMV) infection has been actively implicated in complex neoplastic processes. Beyond oncomodulation, the molecular mechanisms that might underlie HCMV-induced oncogenesis are being extensively studied. Polycomb repressive complex 2 (PRC2) proteins, in particular enhancer of zeste homolog 2 (EZH2) are associated with cancer progression. Nevertheless, little is known about EZH2 activation in the context of HCMV infection and breast oncogenesis.

Methods

Herein, we identified EZH2 as a downstream target for HCMV-induced Myc upregulation upon acute and chronic infection with high-risk strains using a human mammary epithelial model.

Findings

We detected polyploidy and CMV-transformed HMECs (CTH) cells harboring HCMV and dynamically undergoing the giant cells cycle. Acquisition of embryonic stemness markers positively correlated with EZH2 and Myc expression. EZH2 inhibitors curtail sustained CTH cells’ malignant phenotype. Besides harboring polyploid giant cancer cells (PGCCs), tumorigenic breast biopsies were characterized by an enhanced EZH2 and Myc expression, with a strong positive correlation between EZH2 and Myc expression, and between PGCC count and EZH2/Myc expression in the presence of HCMV. Further, we isolated two HCMV strains from EZH2^HighMyc^High basal-like tumors which replicate in MRC5 cells and transform HMECs toward CTH cells after acute infection.

Interpretation

Our data establish a potential link between HCMV-induced Myc activation, the subsequent EZH2 upregulation, and polyploidy induction. These data support the proposed tumorigenesis properties of EZH2/Myc, and allow the isolation of two oncogenic HCMV strains from EZH2^HighMyc^High basal breast tumors while identifying EZH2 as a potential therapeutic target in the management of breast cancer, particularly upon HCMV infection.

Funding

This work was supported by grants from the University of Franche-Comté (UFC) (CR3300), the Région Franche-Comté (2021-Y-08292 and 2021-Y-08290) and the Ligue contre le Cancer (CR3304) to Georges Herbein. Zeina Nehme is a recipient of a doctoral scholarship from the municipality of Habbouch. Sandy Haidar Ahmad is recipient of a doctoral scholarship from Lebanese municipality. Ranim El Baba is a recipient of a doctoral scholarship from Hariri foundation for sustainable human development.

Tumors and Cytomegalovirus: An Intimate Interplay

Human cytomegalovirus (HCMV) is a herpesvirus that alternates lytic and latent infection, infecting between 40 and 95% of the population worldwide, usually without symptoms. During its lytic cycle, HCMV can result in fever, asthenia, and, in some cases, can lead to severe symptoms such as hepatitis, pneumonitis, meningitis, retinitis, and severe cytomegalovirus disease, especially in immunocompromised individuals. Usually, the host immune response keeps the virus in a latent stage, although HCMV can reactivate in an inflammatory context, which could result in sequential lytic/latent viral cycles during the lifetime and thereby participate in the HCMV genomic diversity in humans and the high level of HCMV intrahost genomic variability. The oncomodulatory role of HCMV has been reported, where the virus will favor the development and spread of cancerous cells. Recently, an oncogenic role of HCMV has been highlighted in which the virus will directly transform primary cells and might therefore be defined as the eighth human oncovirus. In light of these new findings, it is critical to understand the role of the immune landscape, including the tumor microenvironment present in HCMV-harboring tumors. Finally, the oncomodulatory/oncogenic potential of HCMV could lead to the development of novel adapted therapeutic approaches against HCMV, especially since immunotherapy has revolutionized cancer therapeutic strategies and new therapeutic approaches are actively needed, particularly to fight tumors of poor prognosis.

Valganciclovir as Add-on to Second-Line Therapy in Patients with Recurrent Glioblastoma

Simple Summary

Patients with glioblastoma have a dismal prognosis. The major challenge with this disease is that it recurs despite aggressive first-line therapy and rapidly becomes therapy resistant. Cytomegalovirus has been found in most glioblastoma tumors and may contribute to tumor aggressiveness. Antiviral therapy may thus represent a novel therapeutic strategy and has shown promising results in patients with newly diagnosed glioblastoma. We performed a retrospective analysis of survival data of 29 patients with recurrent glioblastoma receiving the antiviral drug valganciclovir as an add-on to second-line therapy and of 109 contemporary controls treated at our institution. Valganciclovir was well tolerated and seemed to improve survival after tumor recurrence in patients with recurrent disease both in re-operated and non-re-operated patients and in patients with unmethylated and methylated MGMT promoter status. Prospective controlled clinical studies on patients with recurrent glioblastoma are warranted to evaluate if valganciclovir treatment offers a novel therapeutic option.

Abstract

Glioblastoma invariably recurs despite aggressive and multimodal first-line treatment and no standardized second-line therapy exists. We previously reported that treatment with the antiviral drug valganciclovir as an add-on to standard therapy significantly prolonged overall survival in 102 patients with newly diagnosed glioblastoma compared to contemporary controls. Here we present the results of retrospective survival analyses including patients with glioblastoma that initiated valganciclovir therapy after recurrence. Twenty-nine patients with recurrent glioblastoma received valganciclovir as an add-on to second-line therapy at Karolinska University Hospital. Contemporary controls were 109 patients with glioblastoma who received similar second-line therapy at our institution. We retrospectively analyzed survival data of these patients. Patients with recurrent glioblastoma who received valganciclovir had longer median overall survival after recurrence than controls (12.1 vs. 7.4 months, respectively, p = 0.0028). The drug was well tolerated. Both patients who underwent re-operation and patients that were not re-operated after recurrence benefitted significantly from valganciclovir therapy. Valganciclovir prolonged survival after recurrence both in patients with an unmethylated and methylated MGMT promoter gene. Valganciclovir was safe to use and prolonged median survival after recurrence for patients with recurrent glioblastoma, re-operated or not after recurrence, and with methylated or unmethylated MGMT promoter gene.

Human Cytomegalovirus Seropositivity and Viral DNA in Breast Tumors Are Associated with Poor Patient Prognosis

Simple Summary

Human cytomegalovirus (HCMV) infects 40–70% of adult populations in developed countries and this is thought to be involved in breast cancer progression; however, reports of detection of the viral genome in breast tumors ranges from 0–100%. We optimized a method that is both sensitive and specific to detect HCMV DNA in tissues from Canadian breast cancer patients. Only ~42% of HCMV-seropositive patients expressed viral DNA in their breast tumors. Viral transcription was not detected in any HCMV-infected breast tumors, indicating a latent infection; however, HCMV seropositivity and the presence of latent infections in breast tumors were independently, and in combination, associated with increased metastasis. HCMV DNA-positive tumors were also associated with lower relapse-free survival. Therefore, HCMV infection status should be accounted for during the monitoring and treatment of breast cancer patients. Prevention or reducing the effects of HCMV infection could decrease morbidity and mortality from metastatic disease.

Abstract

Human cytomegalovirus (HCMV) infects 40–70% of adults in developed countries. Detection of HCMV DNA and/or proteins in breast tumors varies considerably, ranging from 0–100%. In this study, nested PCR to detect HCMV glycoprotein B (gB) DNA in breast tumors was shown to be sensitive and specific in contrast to the detection of DNA for immediate early genes. HCMV gB DNA was detected in 18.4% of 136 breast tumors while 62.8% of 94 breast cancer patients were seropositive for HCMV. mRNA for the HCMV immediate early gene was not detected in any sample, suggesting viral latency in breast tumors. HCMV seropositivity was positively correlated with age, body mass index and menopause. Patients who were HCMV seropositive or had HCMV DNA in their tumors were 5.61 (CI 1.77–15.67, p = 0.003) or 5.27 (CI 1.09–28.75, p = 0.039) times more likely to develop Stage IV metastatic tumors, respectively. Patients with HCMV DNA in tumors experienced reduced relapse-free survival (p = 0.042). Being both seropositive with HCMV DNA-positive tumors was associated with vascular involvement and metastasis. We conclude that determining the seropositivity for HCMV and detection of HCMV gB DNA in the breast tumors could identify breast cancer patients more likely to develop metastatic cancer and warrant special treatment.

Distinct Oncogenic Transcriptomes in Human Mammary Epithelial Cells Infected With Cytomegalovirus

Human cytomegalovirus is being recognized as a potential oncovirus beside its oncomodulation role. We previously isolated two clinical isolates, HCMV-DB (KT959235) and HCMV-BL (MW980585), which in primary human mammary epithelial cells promoted oncogenic molecular pathways, established anchorage-independent growth in vitro, and produced tumorigenicity in mice models, therefore named high-risk oncogenic strains. In contrast, other clinical HCMV strains such as HCMV-FS, KM, and SC did not trigger such traits, therefore named low-risk oncogenic strains. In this study, we compared high-risk oncogenic HCMV-DB and BL strains (high-risk) with low-risk oncogenic strains HCMV-FS, KM, and SC (low-risk) additionally to the prototypic HCMV-TB40/E, knowing that all strains infect HMECs in vitro. Numerous pro-oncogenic features including enhanced expression of oncogenes, cell survival, proliferation, and epithelial-mesenchymal transition genes were observed with HCMV-BL. In vitro, mammosphere formation was observed only in high-risk strains. HCMV-TB40/E showed an intermediate transcriptome landscape with limited mammosphere formation. Since we observed that Ki67 gene expression allows us to discriminate between high and low-risk HCMV strains in vitro, we further tested its expression in vivo. Among HCMV-positive breast cancer biopsies, we only detected high expression of the Ki67 gene in basal tumors which may correspond to the presence of high-risk HCMV strains within tumors. Altogether, the transcriptome of HMECs infected with HCMV clinical isolates displays an “oncogenic gradient” where high-risk strains specifically induce a prooncogenic environment which might participate in breast cancer development.

Multifocal EBV-associated smooth muscle tumors in a patient with cytomegalovirus infection after liver transplantation: a case report from Shiraz, Iran

Introduction

Immunodeficient patients, including the recipients of solid organs, exhibit an increase in the incidence of neoplasms. Post-transplant smooth muscle tumor (PTSMT) is a distinct and infrequent entity of these groups of neoplasms. Epstein–Barr virus (EBV) is considered to be involved in the etiology of this neoplasm.

Case report

A 28-year-old man who underwent liver transplantation presented with abdominal pain and diarrhea for several months. He had a history of resistant systemic cytomegalovirus (CMV) infection after transplantation. Radiologic evaluation and colonoscopy revealed multiple liver, spleen, lung, and colon lesions. Microscopic assessment of colon and liver lesions using IHC study were in favor of spindle cell proliferation with mild atypia and a mild increase in mitotic rate without any necrosis, with features of smooth muscle tumor. Considering the transplantation history, EBER chromogenic in situ hybridization (CISH) study on paraffin blocks was requested, which demonstrated EBV RNA in tumor cell nuclei, suggesting EBV-associated smooth muscle tumor. In addition, PCR for CMV on paraffin blocks was positive. PCR for EBV and CMV viremia were negative. The dosage of immunosuppressive agents was reduced, and currently, he is being followed, with slow expansion in the size of the lesions.

Conclusion

Although the incidence of post-transplant smooth muscle tumors (PTSMTs) is low, it should be remained in the differential diagnosis in post-transplantation patients, especially dealing with multifocal tumors. As strong stimulant for smooth muscle tumors, close follow-up and screening for EBV and CMV infection and early treatment at the time of diagnosis are recommended to avoid these virus-induced tumors.

Molecular Detection of Human Cytomegalovirus in Breast Cancer of Iranian Women Using Real-Time PCR

Background: The role of carcinogenic viruses in developing breast cancer has not yet been identified. Many studies have examined the association between breast cancer and human cytomegalovirus (HCMV), but conflicting results have been reported. Objectives: The aim of this study was to evaluate the levels of IgM & IgG antibodies against HCMV by identifying the viral genome in the breast tissue of women with breast cancer. Methods: A total of 60 patients with breast cancer and 60 healthy individuals (40 cases with fibroadenoma and 20 healthy samples) were selected. Serum levels of IgM & IgG antibodies against HCMV were measured by ELISA, and after DNA extraction from the breast tissue, the presence of the cytomegaloviruses (CMV) genome was assessed by Real-Time PCR. Results: Real-time PCR results showed that 20 samples of breast cancer tissue and 5 samples of fibroadenoma were positive for CMV genome (P = 0.001, OR: 5.50, CI 95%: 1.90 - 15.89). All samples had CMV-IgG antibody in their serum, but their mean serum level was higher in the cancer group (48.27 ± 15.99 U/mL) than the control group (40.11 ± 18.01 U/mL) (P = 0.004). However, CMV-IgM anti-viral antibody was positive in 5 cases with cancer and 3 cases in the control group. The mean serum concentration of this antibody was higher in the cancer group (6.60 ± 6.75 U/mL) than the control group (4.92 ± 3.03 U/mL) (P = 0.099). Conclusions: Increased serum levels of anti-CMV antibodies in patients with cancer, as well as the presence of viral genomes in some cases, indicate the carcinogenesis effect of the virus.

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.

Immune Landscape of CMV Infection in Cancer Patients: From "Canonical" Diseases Toward Virus-Elicited Oncomodulation

Human Cytomegalovirus (HCMV) is an immensely pervasive herpesvirus, persistently infecting high percentages of the world population. Despite the apparent robust host immune responses, HCMV is capable of replicating, evading host defenses, and establishing latency throughout life by developing multiple immune-modulatory strategies. HCMV has coexisted with humans mounting various mechanisms to evade immune cells and effectively win the HCMV-immune system battle mainly through maintaining its viral genome, impairing HLA Class I and II molecule expression, evading from natural killer (NK) cell-mediated cytotoxicity, interfering with cellular signaling, inhibiting apoptosis, escaping complement attack, and stimulating immunosuppressive cytokines (immune tolerance). HCMV expresses several gene products that modulate the host immune response and promote modifications in non-coding RNA and regulatory proteins. These changes are linked to several complications, such as immunosenescence and malignant phenotypes leading to immunosuppressive tumor microenvironment (TME) and oncomodulation. Hence, tumor survival is promoted by affecting cellular proliferation and survival, invasion, immune evasion, immunosuppression, and giving rise to angiogenic factors. Viewing HCMV-induced evasion mechanisms will play a principal role in developing novel adapted therapeutic approaches against HCMV, especially since immunotherapy has revolutionized cancer therapeutic strategies. Since tumors acquire immune evasion strategies, anti-tumor immunity could be prominently triggered by multimodal strategies to induce, on one side, immunogenic tumor apoptosis and to actively oppose the immune suppressive microenvironment, on the other side.

Cytomegalovirus subverts macrophage identity

Cytomegaloviruses (CMVs) have co-evolved with their mammalian hosts for millions of years, leading to remarkable host specificity and high infection prevalence. Macrophages, which already populate barrier tissues in the embryo, are the predominant immune cells at potential CMV entry sites. Here we show that, upon CMV infection, macrophages undergo a morphological, immunophenotypic, and metabolic transformation process with features of stemness, altered migration, enhanced invasiveness, and provision of the cell cycle machinery for viral proliferation. This complex process depends on Wnt signaling and the transcription factor ZEB1. In pulmonary infection, mouse CMV primarily targets and reprograms alveolar macrophages, which alters lung physiology and facilitates primary CMV and secondary bacterial infection by attenuating the inflammatory response. Thus, CMV profoundly perturbs macrophage identity beyond established limits of plasticity and rewires specific differentiation processes, allowing viral spread and impairing innate tissue immunity.

Viral Manipulation of the Host Epigenome as a Driver of Virus-Induced Oncogenesis

Tumorigenesis due to viral infection accounts for a high fraction of the total global cancer burden (15–20%) of all human cancers. A comprehensive understanding of the mechanisms by which viral infection leads to tumor development is extremely important. One of the main mechanisms by which viruses induce host cell proliferation programs is through controlling the host’s epigenetic machinery. In this review, we dissect the epigenetic pathways through which oncogenic viruses can integrate their genome into host cell chromosomes and lead to tumor progression. In addition, we highlight the potential use of drugs based on histone modifiers in reducing the global impact of cancer development due to viral infection.

Productive Infection of Human Breast Cancer Cell Lines with Human Cytomegalovirus (HCMV)

Breast cancer is the leading cause of cancer deaths among women worldwide. There are many known risk factors for breast cancer, but the role of infectious disease remains unclear. Human cytomegalovirus (HCMV) is a widespread herpesvirus that usually causes little disease. Because HCMV has been detected in breast tumor biopsy samples and is frequently transmitted via human breast milk, we investigated HCMV replication in breast tumor cells. Four human breast cancer cell lines with different expression profiles for the key diagnostic markers of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), were infected with a bacterial artificial chromosome-derived HCMV clinical strain TB40/E tagged with green fluorescent protein (GFP). Fluorescence microscopy confirmed that all four breast cancer cell lines supported virus entry. RNA was isolated from infected cells and the expression of immediate early (UL123), early (UL54), and late (UL111A) genes was confirmed using PCR. Viral proteins were detected by immunoblotting, and viral progeny were produced during the infection of breast tumor cells, as evidenced by subsequent infection of fibroblasts with culture supernatants. These results demonstrate that breast tumor cells support productive HCMV infection and could indicate that HCMV replication may play a role in breast cancer progression.

Detection of Human Cytomegalovirus Proteins in Paraffin-Embedded Breast Cancer Tissue Specimens-A Novel, Automated Immunohistochemical Staining Protocol

Emerging evidence supports a significant association between human cytomegalovirus (HCMV) and human malignancies, suggesting HCMV as a human oncomodulatory virus. HCMV gene products are found in >90% of breast cancer tumors and seem to be correlated with more aggressive disease. The definitive diagnosis of HCMV relies on identification of virus inclusions and/or viral proteins by different techniques including immunohistochemical staining. In order to reduce biases and improve clinical value of HCMV diagnostics in oncological pathology, automation of the procedure is needed and this was the purpose of this study. Tumor specimens from 115 patients treated for primary breast cancer at Akershus University Hospital in Norway were available for the validation of the staining method in this retrospective study. We demonstrate that our method is highly sensitive and delivers excellent reproducibility for staining of HCMV late antigen (LA), which makes this method useful for future routine diagnostics and scientific applications.

Patients with Helicobacter pylori-positive gastric cancer with human cytomegalovirus infection have a low tendency of advanced lymphatic metastasis in a Chinese population

Recognized as a group I carcinogen for gastric cancer (GC) and a factor involved in the development of GC, Helicobacter pylori serves a major part in GC research. However, most studies have focused on H. pylori itself, ignoring the complicated pathogenic microbiological environment of GC and neglecting the synergistic or antagonistic effects of H. pylori with other pathogenic microorganisms. Increasing evidence has revealed that the human cytomegalovirus (HCMV) is present in several types of tumors and serves an important role in the neoplastic process of certain human malignant tumors, including GC. The aim of the present study was to explore the role of HCMV and H. pylori co-infection in GC. HCMV and H. pylori infection was analyzed in paired gastric tumor and peri-tumoral tissues from 134 (98 male and 36 female) patients using PCR. The results revealed that a total of 74 (55.2%) patients had H. pylori infection, 58 patients (43.3%) had HCMV infection, and 34 (25.4%) patients had both HCMV and H. pylori infection. Univariate and multivariate analyses demonstrated that H. pylori infection was independently associated with advanced lymphatic metastasis [P=0.007; odds ratio (OR)=3.51]. Furthermore, compared with HCMV-/H. pylori -, neither HCMV+/H. pylori - nor HCMV+/H. pylori + were associated with metastasis, but HCMV-/H. pylori + co-infection status was an independent risk factor for advanced lymphatic metastasis (P=0.005; OR=6.00). In conclusion, GC co-infected with HCMV and H. pylori exhibited a low tendency of lymph node metastasis. HCMV may interact with H. pylori to inhibit the process of lymphatic metastasis, and the mechanism requires further investigation.

Human cytomegalovirus and Epstein-Barr virus infections in breast cancer: A molecular study on Iranian women

BACKGROUND AND OBJECTIVES

The role of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) infections in breast cancer pathology is not well understood. Our study aimed to investigate the association of HCMV and EBV infections with breast cancer and distinguish the types of positive EBV and LMP-1 samples in Iranian patients.

METHODS

Seventy-two formalin-fixed paraffin-embedded (FFPE) breast cancer tissues were analyzed between December 2014 and April 2016. Samples were analyzed for HCMV and EBV using nested-PCR and conventional PCR assays, respectively. Statistical analysis was performed using SPSS software version 18.

RESULTS

Overall, HCMV and EBV genomes were detected in 6.9% and 16.7% of FFPE breast cancer tissues, respectively. Clinical factors were not statistically associated with the presence of HCMV and EBV.

CONCLUSION

In this study, we reported EBV and LMP-1 typing in breast carcinoma cases for the first time in Iran. Our findings indicate that HCMV and EBV infections are not associated with the development of breast cancer.

Polyploid giant cancer cells, stemness and epithelial-mesenchymal plasticity elicited by human cytomegalovirus

A growing body of evidence is recognizing human cytomegalovirus (HCMV) as a potential oncogenic virus. We hereby provide the first experimental in vitro evidence for HCMV as a reprogramming vector, through the induction of dedifferentiation of mature human mammary epithelial cells (HMECs), generation of a polyploid giant cancer cell (PGCC) phenotype characterized by sustained growth of blastomere-like cells, in concordance with the acquisition of embryonic stem cells characteristics and epithelial-mesenchymal plasticity. HCMV presence parallels the succession of the observed cellular and molecular events potentially ensuing the transformation process. Correlation between PGCCs detection and HCMV presence in breast cancer tissue further validates our hypothesis in vivo. Our study indicates that some clinical HCMV strains conserve the potential to transform HMECs and fit with a "blastomere-like" model of oncogenesis, which may be relevant in the pathophysiology of breast cancer and other adenocarcinoma, especially of poor prognosis.

The Association of Human Herpesviruses with Malignant Brain Tumor Pathology and Therapy: Two Sides of a Coin

The role of certain viruses in malignant brain tumor development remains controversial. Experimental data demonstrate that human herpesviruses (HHVs), particularly cytomegalovirus (CMV), Epstein–Barr virus (EBV) and human herpes virus 6 (HHV-6), are implicated in brain tumor pathology, although their direct role has not yet been proven. CMV is present in most gliomas and medulloblastomas and is known to facilitate oncomodulation and/or immunomodulation, thus promoting cancer cell proliferation, invasion, apoptosis, angiogenesis, and immunosuppression. EBV and HHV-6 have also been detected in brain tumors and high-grade gliomas, showing high rates of expression and an inflammatory potential. On the other hand, due to the neurotropic nature of HHVs, novel studies have highlighted the engagement of such viruses in the development of new immunotherapeutic approaches in the context of oncolytic viral treatment and vaccine-based strategies against brain tumors. This review provides a comprehensive evaluation of recent scientific data concerning the emerging dual role of HHVs in malignant brain pathology, either as potential causative agents or as immunotherapeutic tools in the fight against these devastating diseases.

Cytomegalovirus and systemic inflammation at time of surgery is associated with worse outcomes in serous ovarian cancer

OBJECTIVES

Cytomegalovirus (CMV) is a common infection that establishes latency in healthy people. CMV has been associated with alterations of the immune compartment leading to improved responses, while inflammation has been shown to adversely impact outcomes. We investigated whether CMV serostatus predicts outcomes in ovarian cancer in the presence or absence of inflammation.

METHODS

A total of 106 patients with serous ovarian cancer from 2006 to 2009 were analyzed. CMV and systemic inflammation was measured using CMV immunoglobulin G (IgG) and C-reactive protein (CRP), respectively, in serum collected prior to cytoreduction. Patients were stratified by CMV IgG (non-reactive, reactive/borderline) and CRP (≤10, >10 mg/L) status. Overall survival (OS) and recurrence-free survival (RFS) were compared by group using log-rank tests and Cox proportional hazards regression models adjusting for age at surgery.

RESULTS

Of 106 eligible patients, 40 (37.7%) were CMV+/CRP+, 24 (22.6%) CMV+/CRP-, 19 (17.9%) CMV-/CRP+, and 23 (21.7%) CMV-/CRP-. CRP+ had higher CA-125 levels (P = 0.05) and higher rates of suboptimal debulking (P = 0.03). There were no other significant differences in demographic, surgical, or pathologic factors between groups. CMV+/CRP+ patients median RFS and OS were 16.9 months (95% CI: 9.0-21.1) and 31.7 months (95% CI: 25.0-48.7), respectively, with a significantly worse RFS (aHR: 1.85, 95% CI: 1.05-3.24, P = 0.03) and OS (aHR: 2.12, 95% CI: 1.17-3.82, P = 0.01) compared to CMV-/CRP- (RFS = 31.2 months (95% CI: 16.0-56.4) and OS = 63.8 months (95% CI: 50.7-87.0)). CMV+/CRP- group displayed the longest OS (89.3 months).

CONCLUSIONS

Previous exposure to CMV and high CRP at surgery portended worse RFS and OS compared to women who tested negative. The CMV+/CRP- group had the longest OS, indicating that CMV status alone, in the absence of inflammation, may be protective.

Gamma secretase inhibition impairs HCMV replication by reduction of immediate early gene expression at the transcriptional level

Due to diverse pathogenic potentials, there is a growing need for anti-HCMV agents. In this study, we show that treatment with DAPT, a γ-secretase inhibitor (GSI), impairs HCMV replication as assessed by a progeny assay based on immunostaining. This effect is not limited to DAPT because other GSIs with different structures and distinct mechanisms of action also exhibit a similar level of inhibitory effects on HCMV viral production, indicating that γ-secretase activity is required for efficient HCMV replication. Western blot and qPCR analyses reveal that DAPT does not interfere with the viral entry process, but reduces expression of the immediate early protein IE1 at the transcriptional level. Furthermore, we exclude the possible involvement of Notch signaling pathway during HCMV replication by showing that expression of the dominant-negative form of MAML1, which disrupts the transactivational ability of Notch intracellular domain (NICD), does not reduce viral particle formation, and that NICD cannot rescue the DAPT-treated outcomes. Taken together, these findings indicate that γ-secretase activity plays an important role in a key step of the HCMV life cycle and γ-secretase inhibition could potentially be used as a novel preventive and therapeutic strategy against HCMV infection and HCMV-related diseases.

Interplay Between Calcium and AMPK Signaling in Human Cytomegalovirus Infection

Calcium signaling and the AMP-activated protein kinase (AMPK) signaling networks broadly regulate numerous aspects of cell biology. Human Cytomegalovirus (HCMV) infection has been found to actively manipulate the calcium-AMPK signaling axis to support infection. Many HCMV genes have been linked to modulating calcium signaling, and HCMV infection has been found to be reliant on calcium signaling and AMPK activation. Here, we focus on the cell biology of calcium and AMPK signaling and what is currently known about how HCMV modulates these pathways to support HCMV infection and potentially contribute to oncomodulation.

Valganciclovir as Add-on to Standard Therapy in Glioblastoma Patients

PURPOSE

Several groups have reported a prevalence of human cytomegalovirus (CMV) in glioblastoma close to 100%. Previously, we reported that treatment with the antiviral drug valganciclovir as an add-on to standard therapy significantly prolonged survival in 50 patients with glioblastoma. Here, we present an updated retrospective analysis that includes an additional 52 patients.

EXPERIMENTAL DESIGN

From December 2006 to November 2019, 102 patients with newly diagnosed glioblastoma received valganciclovir as an add-on to standard therapy. No additional toxicity was observed. Contemporary controls were 231 patients with glioblastoma who received similar baseline therapy.

RESULTS

Patients with newly diagnosed glioblastoma receiving valganciclovir had longer median overall survival (OS 24.1 vs. 13.3 months, P < 0.0001) and a 2-year survival rate (49.8% vs. 17.3%) than controls. Median time-to-tumor progression was also longer than in controls; 9.9 (0.7-67.5 months) versus 7.3 (1.2-49 months), P = 0.0003. Valganciclovir improved survival in patients with radical or partial resection and an unmethylated or methylated MGMT promoter gene.

CONCLUSIONS

Valganciclovir prolonged median OS of patients with newly diagnosed glioblastoma (with methylated or unmethylated MGMT promoter gene) and was safe to use.

Viral G protein-coupled receptors as modulators of cancer hallmarks

Herpesviruses encode transmembrane G protein-coupled receptors (GPCRs), which share structural homology to human chemokine receptors. These viral GPCRs include KSHV-encoded ORF74, EBV-encoded BILF1, and HCMV-encoded US28, UL33, UL78 and US27. Viral GPCRs hijack various signaling pathways and cellular networks, including pathways involved in the so-called cancer hallmarks as defined by Hanahan and Weinberg. These hallmarks describe cellular characteristics crucial for transformation and tumor progression. The cancer hallmarks involve growth factor-independent proliferation, angiogenesis, avoidance of apoptosis, invasion and metastasis, metabolic reprogramming, genetic instability and immune evasion amongst others. The role of beta herpesviruses modulating these cancer hallmarks is clearly highlighted by the proliferative and pro-angiogenic phenotype associated with KSHV infection which is largely ascribed to the ORF74-mediated modulation of signaling networks in host cells. For HCMV and Epstein-Bar encoded GPCRs, oncomodulatory effects have been described which contribute to the cancer hallmarks, thereby enhancing oncogenic development. In this review, we describe the main signaling pathways controlling the hallmarks of cancer which are affected by the betaherpesvirus encoded GPCRs. Most prominent among these involve the JAK-STAT, PI(3)K-AKT, NFkB and MAPK signaling nodes. These insights are important to effectively target these viral GPCRs and their signaling networks in betaherpesvirus-associated malignancies.

Cytomegalovirus and cancer-related mortality in the national health and nutritional examination survey

PURPOSE

Cytomegalovirus (HCMV) is a common viral infection that shapes lifelong immunity. A history of infection with HCMV has been associated with many chronic diseases, including cancer. In addition, prospective cohort studies have established that HCMV is associated with all-cause mortality. However, there are limited data regarding HCMV and cancer mortality.

METHODS

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) III study (1988-1994): subjects aged 18 to 98, who had HCMV serology results, did not report having cancer at baseline, and were eligible for mortality follow-up (n = 14,498). Mortality was ascertained until December 2011 using National Death Index (NDI) linkage.

RESULTS

The unadjusted risk of all-cancer mortality was higher in HCMV seropositive individuals (HR 2.74, 95% CI 2.05-3.64). This association was attenuated after adjusting for age (HR 1.39, 95% CI 1.02-1.92), and other covariates (age, sex, race/ethnicity, smoking status, BMI, education, and C-reactive protein (CRP); HR 1.21, 95% CI 0.91-1.81). There was a statistically significant interaction between HCMV and sex (p = 0.01): HCMV seropositivity was associated with increased cancer mortality in men (HR 1.65, 95% CI 0.99-2.73) but not in women (HR 0.95, 95% CI 0.59-1.54).

CONCLUSION(S)

Consistent with prior reports, HCMV seropositivity may be associated with an increased risk of cancer-related mortality but the association is partially driven by socioeconomic status and other risk factors. Future research is needed to determine whether HCMV is a risk factor for cancer, as well as identify the specific cancer types where HCMV increases mortality.

Diagnosis of human cytomegvirus association with malignant gliomas and pro- and anti-inflammatories

The study was conducted on seventy individuals of both genders who have been exposed to human cytomegalovirus, a common illness in Iraq. Total cases of human cytomegvirus associated with malignant brain tumors were detected by a real time PCR technique. This resulted in only thirty-six cases of true infection. Of these 24 cases were female, while 12 cases of male infected. The titer to assay the presence of anti- and pro-inflammatories was assessed in sera of all patients by using ELISA kits to evaluate cytokines. This indicated that the pro-inflammatory IL12, after seven days increased (1.67±0.23 pg/ml), while IL4, an anti-inflammatory, decreased to reach (0.39±0.16 pg/ml) (at p<0.05) in the plasm of the experimental patients compared with the control group.

Human Cytomegalovirus Infection Induces High Expression of Prolactin and Prolactin Receptors in Ovarian Cancer

One of the potential biomarkers for ovarian cancer patients is high serum level of prolactin (PRL), which is a growth factor that may promote tumor cell growth. The prolactin receptor (PRLR) and human cytomegalovirus (HCMV) proteins are frequently detected in ovarian tumor tissue specimens, but the potential impact of HCMV infection on the PRL system have so far not been investigated. In this study, HCMV’s effects on PRL and PRLR expression were assessed in infected ovarian cancer cells (SKOV3) by PCR and Western blot techniques. The levels of both PRL and PRLR transcripts as well as the corresponding proteins were highly increased in HCMV-infected SKOV3 cells. Tissue specimens obtained from 10 patients with ovarian cancer demonstrated high expression of PRLR, HCMV-IE, and pp65 proteins. Extensive expression of PRLR was detected in all examined ovarian tumor tissue specimens except for one from a patient who had focal expression of PRLR and this patient was HCMV-negative in her tumor. In conclusion, PRL and PRLR were induced to high levels in HCMV-infected ovarian cancer cells and PRLR expression was extensively detected in HCMV-infected ovarian tissue specimens. Highly induced PRL and PRLR by HCMV infection may be of relevance for the oncomodulatory role of this virus in ovarian cancer.

Human alpha and beta herpesviruses and cancer: passengers or foes?

Based on seroepidemiological studies, human herpes simplex virus types 1 and 2 (HSV-1, HSV-2) are put in relation with a number of cancer diseases; however, they do not appear to play a direct role, being only considered cofactors. Their ability to transform the cells in vitro could be demonstrated experimentally by removing their high lytic ability by a certain dose of UV radiation or by photoinactivation in the presence of photosensitizers, such as neutral red or methylene blue, or culturing under conditions suppressing their lytic activity. However, recent studies indicate that UV irradiated or photoinactivated HSV-1 and HSV-2, able to transform non-transformed cells, behave differently in transformed cells suppressing their transformed phenotype. Furthermore, both transforming and transformed phenotype suppressing activities are pertaining only to non-syncytial virus strains. There are some proposed mechanisms explaining their transforming activity. According to the "hit and run" mechanism, viral DNA induces only initiation of transformation by interacting with cellular DNA bringing about mutations and epigenetic changes and is no longer involved in other processes of neoplastic progression. According to the "hijacking" mechanism, virus products in infected cells may activate signalling pathways and thus induce uncontrolled proliferation. Such a product is e.g. a product of HSV-2 gene designated ICP10 that encodes an oncoprotein RR1PK that activates the Ras pathway. In two cases of cancer, in the case of serous ovarian carcinoma and in some prostate tumours, virus-encoded microRNAs (miRNAs) were detected as a possible cofactor in tumorigenesis. And, recently described herpes virus-associated growth factors with transforming and transformation repressing activity might be considered important factors playing a role in tumour formation. And finally, there is a number of evidence that HSV-2 may increase the risk of cervical cancer after infection with human papillomaviruses. A similar situation is with human cytomegalovirus; however, here, a novel mechanism named oncomodulation has been proposed. Oncomodulation means that HCMV infects tumour cells and modulates their malignant properties without having a direct effect on cell transformation.

Functional Profile of Human Cytomegalovirus Genes and Their Associated Diseases: A Review

The human cytomegalovirus (HCMV), whose genome is 235 ± 1.9 kbp long, is a common herpesvirus. However, the functions of many of its genes are still unknown. HCMV is closely associated with various human diseases and infects 60-90% of the global population. It can infect various human cells, including fibroblasts, epithelial cells, endothelial cells, smooth muscle cells, and monocytes. Although HCMV infection is generally asymptomatic and causes subtle clinical symptoms, it can generate a robust immune response and establish a latent infection in immunocompromised individuals, including those with AIDS, transplant recipients, and developing fetuses. Currently available antivirals approved for the treatment of HCMV-associated diseases are limited by dose-limiting toxicity and the emergence of resistance; however, vaccines and immunoglobulins are unavailable. In this review, we have summarized the recent literature on 43 newly identified HCMV genes. We have described their novel functions on the viral replication cycle, latency, and host immune evasion. Further, we have discussed HCMV-associated diseases and current therapeutic targets. Our review may provide a foundational basis for studies aiming to prevent and develop targeted therapies for HCMV-associated diseases.

A Review of the Potential Role of Human Cytomegalovirus (HCMV) Infections in Breast Cancer Carcinogenesis and Abnormal Immunity

Previously recognized classical human onco-viruses can regulate complex neoplastic events, and are estimated to play a role during carcinogenesis in 15-20% of cancer cases. Although the DNA and gene products of several viruses have been found in breast tumors, none of the classical onco-viruses have definitely been linked to the initiation of breast cancer. However, recent evidence shows that human cytomegalovirus (HCMV) gene products are found in >90% of tumors and metastases of breast cancers, and their increased expression can be correlated to a more aggressive breast cancer phenotype. Supporting the active role of HCMV in breast cancer, a specific HCMV strain, HCMV-DB, was recently shown to exert oncogenic transformational activity in breast epithelial cells in vitro, and to give rise to fast-growing, triple-negative breast tumors when injected into immune deficient mice. The same observation holds true for clinical studies implying increased HCMV protein expression in triple negative breast cancer biopsies. In addition to functionally being able to hijack tumor-promoting cellular events, HCMV is known to exhibit a wide range of immunosuppressive effects, which can have radical impact on the tumor microenvironment. HCMV infected cells can avoid recognition and elimination by the immune system by orchestrating polarization of immunosuppressive type II macrophages, preventing antigen presentation, by expressing T cell inhibitory molecules, and possibly, by the induction of regulatory T (Treg) cell responses. These actions would be especially deleterious for the antigenic activation and proliferation of tumor specific CD8⁺ cytotoxic T lymphocytes (CTLs), whose effector functions have recently been targeted by successful, experimental immunotherapy protocols. The recognition of alternative causes and drivers of breast cancer is a pivotal research topic for the development of diagnostics and novel, effective preventive and therapeutic strategies targeting both tumor cells and their microenvironments.

Accelerated cancer aggressiveness by viral oncomodulation: New targets and newer natural treatments for cancer control and treatment

An infectious etiology for a number of cancers has been entertained for over 100 years and modern studies have confirmed that a number of viruses are linked to cancer induction. While a large number of viruses have been demonstrated in a number of types of cancers, most such findings have been dismissed in the past as opportunistic infections, especially with persistent viruses with high rates of infectivity of the world’s populations. More recent studies have clearly shown that while not definitely causing these cancers, these viruses appear capable of affecting the biology of these tumors in such a way as to make them more aggressive and more resistant to conventional treatments. The term oncomodulatory viruses has been used to describe this phenomenon. A number of recent studies have shown a growing number of ways these oncomodulatory viruses can alter the pathology of these tumors by affecting cell-signaling, cell metabolism, apoptosis mechanisms, cell-cell communication, inflammation, antitumor immunity suppression, and angiogenesis. We are also learning that much of the behavior of tumors depends on cancer stem cells and stromal cells within the tumor microenvironment, which participate in extensive, dynamic crosstalk known to affect tumor behavior. Cancer stem cells have been found to be particularly susceptible to infection by human cytomegalovirus. In a number of studies, it has been shown that while only a select number of cells are actually infected with the virus, numerous viral proteins are released into cancer and stromal cells in the microenvironment and these viral proteins are known to affect tumor behavior and aggressiveness.

Cytomegalovirus is a tumor-associated virus: armed and dangerous

Human cytomegalovirus (HCMV) gene products are present in multiple human malignancies, often in specific association with tumor cells and tumor vasculature. Emerging evidence from human and mouse models of CMV infection in cancer indicate that CMV can transform epithelial cells, promote epithelial to mesenchymal transition (EMT) and mesenchymal to epithelial (MET) in tumor cells, promote tumor angiogenesis and proliferation and incapacitate the host anti-CMV immune response. This review will discuss the increasing role of HCMV in human cancer by demonstrating how HCMV is well suited for impacting major themes in oncogenesis including initiation, promotion, progression, metastasis and immune evasion. What emerges is a picture of an extremely versatile pathogen that may play a significant role in human cancer progression and death.

Human Cytomegalovirus DNA among Women with Breast Cancer

Section Title

Breast cancer is the most common cause of death among women worldwide. Although there are many known risk factors in breast cancer development, infectious diseases have appeared as one of the important key to contribute to carcinogenesis formation. The effects of Human Cytomegalovirus (HCMV) on women with breast cancer has been recently studied and reported. To contribute to this research trend, this study was conducted to evaluate the association between HCMV and the women with breast cancer.

Objective:

This experiment aimed to evaluate HCMV DNA in women with breast cancer in Ahvaz city, Iran.

Materials and Methods:

A total of 37 formalin fixed paraffin embedded tissues of the patients with ductal breast carcinoma and 35 paraffin embedded tissues of the patients with fibro adenoma as control group were collected. The deparaffinization of all the samples were carried out and the DNA was extracted. Initially, the PCR test was carried out to detect beta –globulin DNA as an internal control. For those samples positive for beta –globulin DNA, Polymerase Chain reaction (PCR) was used to detect HCMV for the tests and control samples.

Results:

Among 37 ductal breast carcinoma, 20 (54.04%) cases were proved positive for HCMV DNA by PCR. While among the 35 control group (fibroadenoma), 10 (28.57%) cases were positive for HCMV DNA (P >0.028). The prevalences of HCMV DNA among the age groups 30-39, 40-49 and >50 years were 7 (72.22%), 9 (69.23%), 4 (57.14%), respectively (P=0.066). A high frequency of HCMV DNA was detected in tumor grade III, 13/18 (58.33%) compared with tumor grade II, 7/19 (36.84%) (p=0.044). A high frequency of 16/24 (66.66%) of HCMV DNA was found in invasive ductal breast cancer compared with 4/13 (30.76%) HCMV DNA in situ (P<0.028).

Conclusion:

A high prevalence of 54.05% HCMV was found among the patients with ductal carcinoma. The percentages of the high prevalence of HCMV among age group (40-49) years, tumors grades, and invasive stage were (69.23%), (58.33%), (66.66%), respectively. Further study of HCMV in the latency phase in patients with ductal carcinoma would be necessary to extend our knowledge.