Promising predictive molecular biomarkers for cervical cancer (Review).

Cervical cancer (CC) constitutes a serious public health problem. Vaccination and screening programs have notably reduced the incidence of CC worldwide by >80%; however, the mortality rate in low­income countries remains high. The staging of CC is a determining factor in therapeutic strategies: The clinical management of early stages of CC includes surgery and/or radiotherapy, whereas radiotherapy and/or concurrent chemotherapy are the recommended therapeutic strategies for locally advanced CC. The histopathological characteristics of tumors can effectively serve as prognostic markers of radiotherapy response; however, the efficacy rate of radiotherapy may significantly differ among cancer patients. Failure of radiotherapy is commonly associated with a higher risk of recurrence, persistence and metastasis; therefore, radioresistance remains the most important and unresolved clinical problem. This condition highlights the importance of precision medicine in searching for possible predictive biomarkers to timely identify patients at risk of treatment response failure and provide tailored therapeutic strategies according to genetic and epigenetic characteristics. The present review aimed to summarize the evidence that supports the role of several proteins, methylation markers and non­coding RNAs as potential predictive biomarkers for CC.

Gene expression of cardiovascular risk markers in mononuclear cells of pregnant woman in relation to plasma leptin and homocysteine levels: A cross sectional study.

OBJECTIVE: To investigate the relationship between anthropometric, biochemical, and hematologic parameters and serum leptin and homocysteine (Hcy) levels. Also, to determine the effect of leptin and Hcy on expression of genes associated with cardiovascular disease susceptibility (APOA1, LRP1, COX-1, and COX-2) in mononuclear cells of healthy pregnant women. METHODS: Between August 2018 and January 2020, a cross-sectional study was conducted on 161 healthy pregnant women in Tabasco, southeastern Mexico. The study population was classified by trimester, according to gestational pregnancy. Anthropometric, biochemical (leptin and homocysteine), and hematologic data were obtained under fasting conditions. APOA1, LRP1, COX-1, and COX-2 expression in mononuclear cells was evaluated using RT-qPCR. RESULTS: Red cell indices (hemoglobin, hematocrit, and erythrocytes) were negatively and positively correlated with leptin and Hcy levels, respectively, in the first- and second-trimester groups. Increased leptin levels and low red cell indices were significantly associated with BMI <25.0 in the second-trimester group; however, no significant differences were observed in Hcy levels. Increased leptin and Hcy levels were significantly associated with high lipid indicators in the first- and third-trimester groups, respectively. High APOA1 and COX-2 expression was significantly associated with reduced leptin and increased Hcy levels in the second- and third-trimester groups. CONCLUSION: Increased leptin and Hcy levels during pregnancy, mainly associated with modifications in erythrocytes and lipid indices, may lead to early modification of genes related to lipid metabolism (APOA1) and proinflammatory response (COX-2) and, thereby, increase cardiovascular disease risk.

Modulating epigenetic modifications for cancer therapy (Review).

Cancer is a global public health concern. Alterations in epigenetic processes are among the earliest genomic aberrations occurring during cancer development and are closely related to progression. Unlike genetic mutations, aberrations in epigenetic processes are reversible, which opens the possibility for novel pharmacological treatments. Non­coding RNAs (ncRNAs) represent an essential epigenetic mechanism, and emerging evidence links ncRNAs to carcinogenesis. Epigenetic drugs (epidrugs) are a group of promising target therapies for cancer treatment acting as coadjuvants to reverse drug resistance in cancer. The present review describes central epigenetic aberrations during malignant transformation and explains how epidrugs target DNA methylation, histone modifications and ncRNAs. Furthermore, clinical trials focused on evaluating the effect of these epidrugs alone or in combination with other anticancer therapies and other ncRNA­based therapies are discussed. The use of epidrugs promises to be an effective tool for reversing drug resistance in some patients with cancer.

A recombinant monoclonal-based Taenia antigen assay that reflects disease activity in extra-parenchymal neurocysticercosis.

BACKGROUND: Antigen tests for diagnosis and disease monitoring in some types of neurocysticercosis (NCC) are useful but access to testing has been limited by availability of proprietary reagents and/or kits. METHODS/PRINCIPAL FINDINGS: Three previously identified IgM-secreting hybridomas whose IgM products demonstrated specificity to Taenia solium underwent variable heavy and light chain sequencing and isotype conversion to mouse IgG. Screening of these recombinantly expressed IgG anti-Ts hybridomas, identified one (TsG10) with the highest affinity to crude Taenia antigen. TsG10 was then used as a capture antibody in a sandwich antigen detection immunoassay in combination with either a high titer polyclonal anti-Ts antibody or with biotinylated TsG10 (termed TsG10*bt). Using serum, plasma, and CSF samples from patients with active NCC and those from NCC-uninfected patients, ROC curve analyses demonstrated that the TsG10-TsG10-*bt assay achieved a 98% sensitivity and 100% specificity in detecting samples known to be antigen positive and outperformed the polyclonal based assay (sensitivity of 93% with 100% specificity). By comparing levels of Ts antigen (Ag) in paired CSF (n = 10) or plasma/serum (n = 19) samples from well-characterized patients with extra-parenchymal NCC early in infection and at the time of definitive cure, all but 2 (1 from CSF and 1 from plasma) became undetectable. There was a high degree of correlation (r = 0.98) between the Ag levels detected by this new assay and levels found by a commercial assay. Pilot studies indicate that this antigen can be detected in the urine of patients with active NCC. CONCLUSIONS/SIGNIFICANCE: A newly developed recombinant monoclonal antibody-based Ts Ag detection immunoassay is extremely sensitive in the detection of extra-parenchymal NCC and can be used to monitor the success of treatment in the CSF, serum/plasma and urine. The ability to produce recombinant TsG10 at scale should enable use of this antigen detection immunoassay wherever NCC is endemic. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifiers: NCT00001205 - & NCT00001645.

Anthropometric, biochemical, and haematological indicators associated with hyperhomocysteinemia and their relation to global DNA methylation in a young adult population.

Increased homocysteine (Hcy) levels have been associated with a higher risk of cardiovascular and neurodegenerative diseases. Passive DNA demethylation has been suggested as one of the mechanisms implicated in the development of these conditions, and most studies have investigated this relationship in older adult populations. Therefore, this study aimed to evaluate the relationship between corporal composition and biochemical and haematological indicators with plasma homocysteine levels and genome-wide methylation (Alu, LINE-1, and SAT2) in a population of healthy young adults (median age, 18 years). We showed that the prevalence of hyperhomocysteinemia was significantly higher in men (18.5%) than in women (6.6%) (P = 0.034). Increased Hcy level was substantially associated with higher levels of body mass index and visceral fat in females, whereas in males, it was significantly associated with reduced red cell distribution width and high-density lipoprotein (HDL) cholesterol (HDL-C) levels and increased low-density lipoprotein/HDL ratio. Hypomethylation of Alu was significantly associated with reduced levels of HDL-C (<40.0 mg dL-1), whereas hypomethylation of LINE-1 and SAT2 was significantly associated with higher levels of skeletal muscle (<39.3%) in males. These results highlight the participation of hormonal factors in regulating Hcy metabolism, primarily in the female population, whereas changes in DNA methylation observed in males might be associated with the consumption of a protein diet with high levels of methionine, independent of increased Hcy levels.

The high-risk HPV E6 proteins modify the activity of the eIF4E protein via the MEK/ERK and AKT/PKB pathways.

Previous studies have proposed that the human papillomavirus (HPV) E6 oncoproteins modify the transcriptional activity of eIF4E through mechanisms dependent on p53 degradation. However, the effect of these oncoproteins on pathways regulating the activity of the eIF4E protein remains poorly understood. Hence, we investigated the mechanisms whereby E6 proteins regulate the activity of the eIF4E protein and its effect on target genes. Overexpression of E6 constructs (HPV-6, HPV-16, HPV-18, and HPV52) showed that E6 oncoproteins increased phosphorylation of the eIF4E protein (Serine-209). This result was mainly mediated by phosphorylation of the 4EBP1 protein via the PI3K/AKT pathway. Additionally, the pharmacological inhibition of eIF4E phosphorylation in cervical cancer cell lines substantially reduced the protein levels of CCND1 and ODC1, indicating that E6 of the high-risk genotypes may modify protein synthesis of the eIF4E target genes by increasing the activity of the AKT and ERK pathways.

Non-Coding RNAs as Key Regulators of Glutaminolysis in Cancer.

Cancer cells exhibit exacerbated metabolic activity to maintain their accelerated proliferation and microenvironmental adaptation in order to survive under nutrient-deficient conditions. Tumors display an increase in glycolysis, glutaminolysis and fatty acid biosynthesis, which provide their energy source. Glutamine is critical for fundamental cellular processes, where intermediate metabolites produced through glutaminolysis are necessary for the maintenance of mitochondrial metabolism. These include antioxidants to remove reactive oxygen species, and the generation of the nonessential amino acids, purines, pyrimidines and fatty acids required for cellular replication and the activation of cell signaling. Some cancer cells are highly dependent on glutamine consumption since its catabolism provides an anaplerotic pathway to feed the Krebs cycle. Intermediate members of the glutaminolysis pathway have been found to be deregulated in several types of cancers and have been proposed as therapeutic targets and prognostic biomarkers. This review summarizes the main players in the glutaminolysis pathway, how they have been found to be deregulated in cancer and their implications for cancer maintenance. Furthermore, non-coding RNAs are now recognized as new participants in the regulation of glutaminolysis; therefore, their involvement in glutamine metabolism in cancer is discussed in detail.

Mechanisms of Vasculogenic Mimicry in Ovarian Cancer.

Solid tumors carry out the formation of new vessels providing blood supply for growth, tumor maintenance, and metastasis. Several processes take place during tumor vascularization. In angiogenesis, new vessels are derived from endothelial cells of pre-existing vessels; while in vasculogenesis, new vessels are formed de novo from endothelial progenitor cells, creating an abnormal, immature, and disorganized vascular network. Moreover, highly aggressive tumor cells form structures similar to vessels, providing a pathway for perfusion; this process is named vasculogenic mimicry (VM), where vessel-like channels mimic the function of vessels and transport plasma and blood cells. VM is developed by numerous types of aggressive tumors, including ovarian carcinoma which is the second most common cause of death among gynecological cancers. VM has been associated with poor patient outcome and survival in ovarian cancer, although the involved mechanisms are still under investigation. Several signaling molecules have an important role in VM in ovarian cancer, by regulating the expression of genes related to vascular, embryogenic, and hypoxic signaling pathways. In this review, we provide an overview of the current knowledge of the signaling molecules involved in the promotion and regulation of VM in ovarian cancer. The clinical implications and the potential benefit of identification and targeting of VM related molecules for ovarian cancer treatment are also discussed.

Molecular epidemiology of bacterial vaginosis and its association with genital micro-organisms in asymptomatic women.

Introduction. Bacterial vaginosis (BV) is dysbiosis associated with an increased risk of several sexually transmitted infections. It is primarily diagnosed via Gram staining, although molecular analyses have presented higher diagnostic accuracy.Aim. This study aimed to evaluate the molecular epidemiology of BV in asymptomatic women to determine its association with several commensal and pathogenic micro-organisms of the genitalia.Methodology. The prevalence of BV was investigated through semiquantitative assessment of 201 women recruited during their routine gynaecological inspection at an outpatient clinic in Tabasco, Mexico.Results. Women with BV showed an increased prevalence of Chlamydia trachomatis (P=0.021) and Mycoplasma hominis (P=0.001). Of the BV-associated micro-organisms, Gardnerella vaginalis was significantly associated with C. trachomatis (P=0.005) and/or Ureaplasma parvum (P=0.003), whereas Atopobium vaginae and Megasphaera type 1 correlated significantly with Mycoplasma hominis (P=0.001). No significant association was observed between human papillomavirus (HPV) infection and BV, although there was increased prevalence of HPV59, HPV73, HPV52 and HPV58 in women displaying cervical cytological abnormalities.Conclusion. Identification of BV-associated micro-organisms via molecular analysis may help to distinguish recurrent cases from new infections and identify micro-organisms potentially associated with pharmacological resistance.

Correction to: Intratype variants of the E2 protein from human papillomavirus type 18 induce different gene expression profiles associated with apoptosis and cell proliferation.

The Given names of the author Alma Mariana Fuentes-González was incorrectly tagged in original publication and corrected here. The original article has been corrected.

Keratinocyte infection by Actinomadura madurae triggers an inflammatory response.

BACKGROUND: Actinomycetoma is a syndrome of the skin characterized by chronic inflammation and lesions with nodular grain-like structures. The most common aetiological agents are Nocardia brasiliensis and Actinomadura madurae. In response to infection with these organisms the body produces an inflammatory immune response in the skin. The aim of the present study was to determine the production of chemokines, pro-inflammatory cytokines, antimicrobial peptides and the expression of Toll-like receptors (TLRs) in keratinocytes infected by A. madurae. METHODS: A cell line of HaCaT keratinocytes was infected with A. madurae at a multiplicity of infection of 20:1 for 2 h and the samples were collected from 2 to 72 h post-infection. Intracellular replication of the bacterium was evaluated by counting of colony-forming units, the TLR expression and antimicrobial peptide production were assayed by confocal microscopy and chemokine and pro-inflammatory cytokine levels were determined by enzyme-linked immunosorbent assay. RESULTS: Early in the infection, A. madurae was able to achieve intracellular replication in keratinocytes, however, the cells eventually controlled the infection. In response to the infection, keratinocytes overexpressed TLR2 and TLR6, produced high concentrations of cytokines monocyte chemoattractant protein-1, interleukin 8, human ß-defensin-1, human ß-defensin-2 and LL37 and low levels of tumour necrosis factor α. CONCLUSIONS: The human keratinocytes contribute to the inflammatory process in response to A. madurae infection by overexpressing TLRs and producing chemokines, pro-inflammatory cytokines and antimicrobial peptides.

Intratype variants of the E2 protein from human papillomavirus type 18 induce different gene expression profiles associated with apoptosis and cell proliferation.

Persistent infections with high-risk human papillomaviruses (HR-HPVs) are linked to the development of cervical cancer due to a deregulation of the productive viral cycle in the host cell, leading to cell transformation. The E2 viral protein is expressed early during an HPV infection and regulates viral replication and transcription. Other functions have been attributed to E2, such as the promotion of apoptosis that are independent of its role in the regulation of the expression of E6 and E7 viral oncogenes. Moreover, it has been shown that the HPV16 E2 protein has regulatory effects on cellular gene expression, suggesting that it participates in the modulation of different cellular processes. Intratype genomic variations within high-risk HPV types have an impact on the prognosis of HPV-related lesions. Nevertheless, the biological significance of HPV18 E2 intratype variations has not been analysed previously. The aim of this study was to determine whether HPV18 E2 intratype variations differentially modulate gene expression and whether cell-death-related genes are affected by variations in E2. We demonstrate that HPV18 E2 intratype Asian Amerindian (AsAi) and African (Af) variants differentially affect gene expression profiles. Although the E2-AsAi variant was found to modulate a larger number of cellular genes, both E2 variants affected similar cellular processes. Nevertheless, E2-AsAi and E2-Af variants showed differences in their ability to induce apoptosis, where E2-Af had a stronger effect. The differences in gene expression profiles in cells harbouring E2 intratype variants suggest a possible effect on diverse cellular signalling pathways, and this might suggest an approach for identifying biological processes regulated by HPV18 E2 intratype variants.

HPV-18 E6 Oncoprotein and Its Spliced Isoform E6*I Regulate the Wnt/ß-Catenin Cell Signaling Pathway through the TCF-4 Transcriptional Factor.

The Wnt/ß-catenin signaling pathway regulates cell proliferation and differentiation and its aberrant activation in cervical cancer has been described. Persistent infection with high risk human papillomavirus (HR-HPV) is the most important factor for the development of this neoplasia, since E6 and E7 viral oncoproteins alter cellular processes, promoting cervical cancer development. A role of HPV-16 E6 in Wnt/ß-catenin signaling has been proposed, although the participation of HPV-18 E6 has not been previously studied. The aim of this work was to investigate the participation of HPV-18 E6 and E6*I, in the regulation of the Wnt/ß-catenin signaling pathway. Here, we show that E6 proteins up-regulate TCF-4 transcriptional activity and promote overexpression of Wnt target genes. In addition, it was demonstrated that E6 and E6*I bind to the TCF-4 (T cell factor 4) and ß-catenin, impacting TCF-4 stabilization. We found that both E6 and E6*I proteins interact with the promoter of Sp5, in vitro and in vivo. Moreover, although differences in TCF-4 transcriptional activation were found among E6 intratype variants, no changes were observed in the levels of regulated genes. Furthermore, our data support that E6 proteins cooperate with ß-catenin to promote cell proliferation.

Deregulation of the Notch pathway as a common road in viral carcinogenesis.

The Notch pathway is a conserved signaling pathway and a form of direct cell-cell communication related to many biological processes during development and adulthood. Deregulation of the Notch pathway is involved in many diseases, including cancer. Almost 20% of all cancer cases have an infectious etiology, with viruses responsible for at least 1.5 million new cancer cases per year. Seven groups of viruses have been classified as oncogenic: hepatitis B and C viruses (HBV and HCV respectively), Epstein-Barr virus (EBV), Kaposi sarcoma-associated herpesvirus (KSHV), human T lymphotropic virus (HTLV-1), human papillomavirus (HPV), and Merkel cell polyomavirus (MCPyV). These viruses share the ability to manipulate a variety of cell pathways that are critical in proliferation and differentiation, leading to malignant transformation. Viral proteins interact directly or indirectly with different members of the Notch pathway, altering their normal function. This review focuses exclusively on the direct interactions of viral oncoproteins with Notch elements, providing a deeper understanding of the dual behavior of the Notch pathway as activator or suppressor of neoplasia in virus-related cancers.

Regulation of Cellular Metabolism by High-Risk Human Papillomaviruses.

The alteration of glucose metabolism is one of the first biochemical characteristics associated with cancer cells since most of these cells increase glucose consumption and glycolytic rates even in the presence of oxygen, which has been called “aerobic glycolysis" or the Warburg effect. Human papillomavirus (HPV) is associated with approximately 5% of all human cancers worldwide, principally to cervical cancer. E6 and E7 are the main viral oncoproteins which are required to preserve the malignant phenotype. These viral proteins regulate the cell cycle through their interaction with tumor suppressor proteins p53 and pRB, respectively. Together with the viral proteins E5 and E2, E6 and E7 can favor the Warburg effect and contribute to radio- and chemoresistance through the increase in the activity of glycolytic enzymes, as well as the inhibition of the Krebs cycle and the respiratory chain. These processes lead to a fast production of ATP obtained by Warburg, which could help satisfy the high energy demands of cancer cells during proliferation. In this way HPV proteins could promote cancer hallmarks. However, it is also possible that during an early HPV infection, the Warburg effect could help in the achievement of an efficient viral replication.

Loss of nuclear NOTCH1, but not its negative regulator NUMB, is an independent predictor of cervical malignancy.

The participation of NOTCH signaling in invasive cervical cancer (ICC) remains controversial since both tumor suppressive and oncogenic properties have been described. Additionally, the role of NUMB, a negative regulator of NOTCH, remains unclear in ICC. We aimed to investigate the role of NOTCH1 and NUMB expression and their localization in cervical intraepithelial neoplasia (CIN) and ICC samples. A total of 144 biopsies were obtained from the Instituto Nacional de Cancerología, México from 2004 to 2017, and were subjected to immunohistochemistry for NOTCH1 and NUMB. We found that nuclear NOTCH1 expression was more frequently found in CIN samples compared with ICC (77.55% vs. 15.79%, p = 0.001). NUMB was almost exclusively found in the nucleus of CIN samples (32.65% vs. 6.32%, p = 0.001). Cytoplasmic expression of NOTCH1 (44.21%) and NUMB (35.79%) was the most frequent localization in ICC. Multivariable-adjusted analysis showed that the loss of nuclear NOTCH1 expression was an independent predictor of malignancy (ß = -3.428, 95% confidence interval [95% CI] = -5.127, -1.728, p = 0.001). In contrast, the association between cytoplasmic NUMB expression and cervical cancer was lost after adjusting for nuclear NOTCH1 expression (ß = 2.074, 95% [CI] = -0.358, 4.506, P = 0.094). Additionally, patients with cytoplasmic NOTCH1 expression showed a borderline association with longer overall survival (OS) than those with nuclear NOTCH1 expression (P = 0.08). Our data suggest that the loss of nuclear NOTCH1 but not NUMB might be an independent predictor of malignancy in cervical cancer.

The Role of E6 Spliced Isoforms (E6*) in Human Papillomavirus-Induced Carcinogenesis.

Persistent infections with High Risk Human Papillomaviruses (HR-HPVs) are the main cause of cervical cancer development. The E6 and E7 oncoproteins of HR-HPVs are derived from a polycistronic pre-mRNA transcribed from an HPV early promoter. Through alternative splicing, this pre-mRNA produces a variety of E6 spliced transcripts termed E6*. In pre-malignant lesions and HPV-related cancers, different E6/E6* transcriptional patterns have been found, although they have not been clearly associated to cancer development. Moreover, there is a controversy about the participation of E6* proteins in cancer progression. This review addresses the regulation of E6 splicing and the different functions that have been found for E6* proteins, as well as their possible role in HPV-induced carcinogenesis.

Anti-Taenia solium monoclonal antibodies for the detection of parasite antigens in body fluids from patients with neurocysticercosis.

Neurocysticercosis (NCC), an infection of the brain by Taenia solium (Ts) cysts, is the most common cause of adult-onset epilepsy in developing countries. Serological testing consists primarily of varying methods to detect antibodies in body fluids and more recently antigen (Ag) detection assays to identify individuals or animals with viable parasites. Antigen assays currently in use employ monoclonal antibodies (mAbs) raised against T. saginata, which have known cross reactivity to animal cestodes but are highly specific in human samples. We produced, characterized and tested 21 mAbs raised against T. solium whole cyst antigens, vesicular fluid or excretory secretory products. Reactivity of the TsmAbs against specific cyst structures was determined using immunofluorescence and immunohistochemistry on histological sections of Ts muscle cysts. Four TsmAbs reacted to vesicular space alone, 9 to the neck and cyst wall, one to the neck and vesicular space and 7 to the neck, cyst wall and vesicular space. An in-house ELISA assay to detect circulating Ts antigen, using the TsmAbs as capture antibodies and a rabbit polyclonal anti-Ts whole cyst antibody as a detector antibody demonstrated that eight of the 21 TsmAbs detected antigens in known NCC-positive human sera and three of these also in urine samples. Reactivity was expressed as normalized ratios of optical densities (OD positive control/OD negative control). Three TsmAbs had ratios >10 and five between 2 and 10. The TsmAbs have potential utility for the diagnosis and post-treatment monitoring of patients with viable NCC infections.

Regulation of the Wnt/ß-Catenin Signaling Pathway by Human Papillomavirus E6 and E7 Oncoproteins.

Cell signaling pathways are the mechanisms by which cells transduce external stimuli, which control the transcription of genes, to regulate diverse biological effects. In cancer, distinct signaling pathways, such as the Wnt/ß-catenin pathway, have been implicated in the deregulation of critical molecular processes that affect cell proliferation and differentiation. For example, changes in ß-catenin localization have been identified in Human Papillomavirus (HPV)-related cancers as the lesion progresses. Specifically, ß-catenin relocates from the membrane/cytoplasm to the nucleus, suggesting that this transcription regulator participates in cervical carcinogenesis. The E6 and E7 oncoproteins are responsible for the transforming activity of HPV, and some studies have implicated these viral oncoproteins in the regulation of the Wnt/ß-catenin pathway. Nevertheless, new interactions of HPV oncoproteins with cellular proteins are emerging, and the study of the biological effects of such interactions will help to understand HPV-related carcinogenesis. Viruses 2015, 7 4735 This review addresses the accumulated evidence of the involvement of the HPV E6 and E7 oncoproteins in the activation of the Wnt/ß-catenin pathway.