Molecular aspects of cervical cancer: a pathogenesis update.

Cervical cancer (CC) is a significant health problem, especially in low-income countries. Functional studies on the human papillomavirus have generated essential advances in the knowledge of CC. However, many unanswered questions remain. This mini-review discusses the latest results on CC pathogenesis, HPV oncogenesis, and molecular changes identified through next-generation technologies. Interestingly, the percentage of samples with HPV genome integrations correlates with the degree of the cervical lesions, suggesting a role in the development of CC. Also, new functions have been described for the viral oncoproteins E5, E6, and E7, resulting in the acquisition and maintenance of cancer hallmarks, including proliferation, immune response evasion, apoptosis, and genomic instability. Remarkably, E5 oncoprotein affects signaling pathways involved in the expression of interferon-induced genes and EGFR-induced proliferation, while E6 and E7 oncoproteins regulate the DNA damage repair and cell cycle continuity pathways. Furthermore, next-generation technologies provide vast amounts of information, increasing our knowledge of changes in the genome, transcriptome, proteome, metabolome, and epigenome in CC. These studies have identified novel molecular traits associated with disease susceptibility, degree of progression, treatment response, and survival as potential biomarkers and therapeutic targets.

Role of PIGM and PIGX in glycosylphosphatidylinositol biosynthesis and human health (Review).

Glycosylphosphatidylinositol-glycan (GPI) is an anchor to specific cell surface proteins known as GPI-anchored proteins (APs) that are localized in lipid rafts and may act as cell co-receptors, enzymes and adhesion molecules. The present review investigated the significance of GPI biosynthesis class phosphatidylinositol-glycan (PIG)M and PIGX in GPI synthesis and their implications in human health conditions. PIGM encodes GPI-mannosyltransferase I (MT-I) enzyme that adds the first mannose to the GPI core structure. PIGX encodes the regulatory subunit of GPI-MT-I. The present review summarizes characteristics of the coding sequences of PIGM and PIGX, and their expression in humans, as well as the relevance of GPI-MT-I and the regulatory subunit in maintaining the presence of GPI-APs on the cell surface and their secretion. In addition, the association of PIGM mutations with paroxysmal nocturnal hemoglobinuria and certain types of GPI-deficiency disease and the altered expression of PIGM and PIGX in cancer were also reviewed. In addition, their interaction with other proteins was described, suggesting a complex role in cell biology. PIGM and PIGX are critical genes for GPI synthesis. Understanding gene and protein regulation may provide valuable insights into the role of GPI-APs in cellular processes.

Regulation of mitochondrial metabolism by autophagy supports leptin-induced cell migration.

Leptin is an adipokine secreted by adipose tissue, which promotes tumor progression by activating canonical signaling pathways such as MAPK/ERK. Recent studies have shown that leptin induces autophagy, and this process is involved in leptin-induced characteristics of malignancy. Autophagy is an intracellular degradation process associated with different hallmarks of cancer, such as cell survival, migration, and metabolic reprogramming. However, its relationship with metabolic reprogramming has not been clearly described. The purpose of this study was to determine the role of leptin-induced autophagy in cancer cell metabolism and its association with cellular proliferation and migration in breast cancer cells. We used ER+/PR+ and triple-negative breast cancer cell lines treated with leptin, autophagy inhibition, or mitochondrial metabolism inhibitors. Our results show that leptin induces autophagy, increases proliferation, mitochondrial ATP production and mitochondrial function in ER+/PR+ cells. Importantly, autophagy was required to maintain metabolic changes and cell proliferation driven by leptin. In triple-negative cells, leptin did not induce autophagy or cell proliferation but increased glycolytic and mitochondrial ATP production, mitochondrial function, and cell migration. In triple negative cells, autophagy was required to support metabolic changes and cell migration, and autophagy inhibition decreased cellular migration similar to mitochondrial inhibitors. In conclusion, leptin-induced autophagy supports mitochondrial metabolism in breast cancer cells as well as glycolysis in triple negative cells. Importantly, leptin-induced mitochondrial metabolism promoted cancer cell migration.

Detection of Sialic Acid to Differentiate Cervical Cancer Cell Lines Using a Sambucus nigra Lectin Biosensor.

Pap smear screening is a widespread technique used to detect premalignant lesions of cervical cancer (CC); however, it lacks sensitivity, leading to identifying biomarkers that improve early diagnosis sensitivity. A characteristic of cancer is the aberrant sialylation that involves the abnormal expression of α2,6 sialic acid, a specific carbohydrate linked to glycoproteins and glycolipids on the cell surface, which has been reported in premalignant CC lesions. This work aimed to develop a method to differentiate CC cell lines and primary fibroblasts using a novel lectin-based biosensor to detect α2,6 sialic acid based on attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and chemometric. The biosensor was developed by conjugating gold nanoparticles (AuNPs) with 5 µg of Sambucus nigra (SNA) lectin as the biorecognition element. Sialic acid detection was associated with the signal amplification in the 1500-1350 cm-1 region observed by the surface-enhanced infrared absorption spectroscopy (SEIRA) effect from ATR-FTIR results. This region was further analyzed for the clustering of samples by applying principal component analysis (PCA) and confidence ellipses at a 95% interval. This work demonstrates the feasibility of employing SNA biosensors to discriminate between tumoral and non-tumoral cells, that have the potential for the early detection of premalignant lesions of CC.

Galectin-9 Expression is Correlated to Cervical Squamous Cell Carcinoma Progression and Overall Survival.

Purpose: To determine whether galectin-9 gene (LGALS9) expression is correlated with cervical cancer progression, clinicopathological characteristics, and overall survival. To determine the biological processes and the abundance of tumour infiltrating immune cells related to the expression of LGALS9. Patients and Methods: The study was conducted in two phases: 1) The expression level of LGALS9 was determined using the data of 193 squamous cell carcinoma (SCC) samples from The Cancer Genome Atlas (TCGA) database. Biological processes and tumour infiltrating cells associated to LGALS9 expression were evaluated using gene set enrichment analysis (GSEA) and tumour immune estimation resource (TIMER). 2) Independently, galectin-9 was identified in 40 SCC samples by immunohistochemistry and optical density quantified using ImagePro® software. Results: The LGALS9 gene showed increased expression in cervical cancer samples. A higher expression level in SCC was related to better overall survival and to early clinical stages. GSEA showed that tumours with higher expression of LGALS9 were enriched in immune pathways such as interferon_alpha_response, and complement, the analysis of TIMER database showed a positive correlation between the expression level of LGALS9 and the abundance of tumour infiltrating immune cells. In addition, higher expression of galectin-9 was found in biopsies of SCC patients at early clinical stages, showing a trend of better survival. Conclusion: Higher expression levels of LGALS9 and galectin-9 in SCC were related to early clinical stages and better prognosis. GSEA and TIMER analysis suggested that galectin-9 could play an antitumor role in cervical SCC.

Neoplasia cervical e infección por virus del papiloma humano como factores de riesgo para desarrollo de cáncer anal y lesiones precursoras / Cervical neoplasia and human papilloma virus infection as risk factors for the development of anal cancer and precursor lesions

RESUMEN La incidencia del cáncer anal ha presentado un incremento en los últimos 10 años, sobre todo en población considerada vulnerable. Las mujeres con antecedentes de infección por Virus del Papiloma Humano (VPH) en el tracto genital, tienen mayor riesgo de este tipo de cáncer. Se ha demostrado que, la infección con genotipos de VPH de alto riesgo (AR), en la región anogenital, desempeña un papel en la etiopatogenia de dicho cáncer. Se desconocen muchos aspectos de la historia natural de las lesiones anales, pero se considera que la zona de transición anal presenta un alto recambio celular, por lo que se ha planteado un mecanismo fisiopatológico de infección por VPH-AR y desarrollo de lesiones invasoras, similar al del cáncer cervical. El objetivo de este trabajo fue mostrar el estado actual sobre la información epidemiológica que vincula el riesgo de desarrollar cáncer anal en mujeres con lesiones precursoras de cáncer cervical asociadas a la infección por VPH. La relevancia de dicha información es proporcionar una base de recomendaciones para la detección oportuna de cáncer anal en mujeres consideradas de AR de padecerlo y, favorecer la realización de estudios prospectivos en la población.

ABSTRACT The incidence of anal cancer has increased in the last 10 years, especially in the population considered to be at risk. Women with a history of infection in the genital tract by Human Papillomavirus (HPV) have higher risk of developing this type of cancer. The presence of high-risk (HR) HPV genotypes in the anogenital region has been shown to play a role in the etiopathogenesis of anal cancer. Many aspects of the natural history of anal lesions are unknown, but the anal transition zone is considered to have a high cell replacement. This is why a pathophysiological mechanism of HR-HPV infection and development of invasive lesions similar to those of cervical cancer has been suggested. The aim of this work was to show the current status of the epidemiological information that links the risk of developing anal cancer in women with cervical cancer precursor lesions associated with HPV infection. The relevance of this information is to provide a basis of recommendations for the timely detection of anal cancer in women considered to be at HR of suffering it, and to encourage more prospective studies in this population.

Identification of Human Papillomavirus genotypes in juvenile laryngeal papillomatosis. Three-year experience in a concentration hospital in Puebla, Mexico / Identificación de genotipos de Virus del Papiloma Humano en papilomatosis laríngea juvenil. Experiencia de 3 años en un hospital de concentración en Puebla, México

Background: Juvenile laryngeal papillomatosis (JLP) is a chronic benign disease from viral etiology, whose clinical course can be aggressive. In Mexico, the Human Papillomavirus (HPV) genotypes that cause this disease have been poorly studied. Objective: To identify the HPV genotypes in patients with JLP in a reference Hospital in Puebla, Mexico. Mehods: A retrospective descriptive study was performed in patients with JLP attended in a 3rd level care of the Instituto Mexicano del Seguro Social in Puebla, México, from 2018 to 2021. Medical records were revised. In all patients, HPV identification was performed by polymerase chain reaction for genomes 6, 11, 16 and 18 using specific oligonucleotides. Descriptive statistics were applied. Results: 9 patients were included, 56% women, mean age 9.5 ±5.7 years; 7 patients were HPV-11 positive and 2 HPV-6. The mean age at diagnosis was 2.35 ±1.77 years, with an average of 12 ±11.56 surgical procedures; 5 patients were tracheostomy carriers, 4 had genotype 11; 8 patients were born vaginally, but no patient had maternal genital condylomatous lesions. In the patient born by cesarean section, transmission due to sexual abuse was documented. Conclusions: The most frequent genotypes in patients with JLP in the south-central region of Mexico are HPV-6 and HPV-11, the latter one is predominating.

Introducción: La papilomatosis laríngea juvenil (PLJ) es una enfermedad benigna crónica de etiología viral, que tiende a tomar un curso clínico agresivo. En México se han estudiado pobremente los genotipos del Virus del Papiloma Humano (VPH) que causan la enfermedad. Objetivo: Identificar los genotipos del VPH en los pacientes con PLJ en un hospital de concentración en Puebla, México. Métodos: Se realizó un estudio descriptivo y retrospectivo a los pacientes con papilomatosis laríngea juvenil atendidos en un hospital de 3er nivel de atención del Instituto Mexicano del Seguro Social en Puebla, México, en el periodo 2018-2021. Se realizó revisión de expedientes clínicos. En todos los pacientes se identificó el VPH por reacción en cadena de polimerasa para los genomas 6, 11, 16 y 18 utilizando oligonulceótidos específicos. Se aplicó estadística descriptiva. Resultados: Se incluyeron 9 pacientes, 56% mujeres, edad media 9.5 ±5.7 años; 7 pacientes registraron positividad al VPH-11 y 2 al VPH-6. La edad media al diagnóstico fue de 2.35 ±1.77 años, con promedio de procedimientos quirúrgicos de 12 ±11.56; de los 5 pacientes portadores de traqueostomía, 4 fueron positivos a VPH-11; 8 pacientes nacieron por vía vaginal, sin embargo, en ningún caso se reportaron lesiones condilomatosas maternas. En el paciente nacido por cesárea, se documentó transmisión por abuso sexual. Conclusiones: Los genotipos más frecuentes en pacientes con PLJ en la región centro-sur de México son VPH-6 y VPH-11, predominando este último.

Serum Levels of Galectin-9 are Increased in Cervical Cancer Patients and are Higher in Advanced Clinical Stages.

Purpose: Cervical cancer (CC) is the second most frequent cancer in undeveloped countries. Serum biomarkers could be useful for evaluation of the treatment response and as a complementary means to improve diagnosis. The expression of galectin-9 is altered in cancer tissue, and higher concentrations are found in the serum of cancer patients. The objectives of this study were (a) to determine the serum galectin-9 concentration in patients with intraepithelial lesions and CC, (b) to determine if the concentration was related to the clinicopathological characteristics and (c) to determine if the galectin-9 concentration was related to its expression level in tumour tissue. Patients and Methods: In all, 222 serum samples from women with different diagnoses, including premalignant lesions and CC, as well as samples from women with normal cytology were included in the study. The serum galectin-9 concentration was determined by ELISA. To evaluate the expression level of galectin-9 in CC tissue, immunohistochemistry was performed in 34 CC biopsy specimens. Results: The galectin-9 concentration in the serum of CC patients (8.171 ng/mL) was increased compared with serum from women with normal epithelia (4.654 ng/mL) and those with low-grade (4.806 ng/mL) and high-grade (5.354 ng/mL) intraepithelial lesions (p value < 0.0001). The area under the ROC curve considering the CC group and the control group was 0.882. The optimal cut-off value was ≥6.88 ng/mL, the specificity obtained was 100%, and the sensitivity was 68.2%. In the CC group, the analysis of the clinical stage showed an increase of galectin-9 in the advanced stage IV group. Serum galectin-9 was not related to the level of galectin-9 expression in tissue, which suggests that galectin-9 is not secreted by tumour cells. Conclusion: The serum galectin-9 concentration is related to cancer progression, as the level of this protein is higher in patients with advanced-stage disease.

Low Activation of CD8+ T Cells in response to Viral Peptides in Mexican Patients with Severe Dengue.

It is acknowledged that antiviral immune response contributes to dengue immunopathogenesis. To identify immunological markers that distinguish dengue fever (DF) and dengue hemorrhagic fever (DHF), 113 patients with confirmed dengue infection were analyzed at 6 or 7 days after fever onset. Peripheral blood mononuclear cells (PBMC) were isolated, lymphocyte subsets and activation biomarkers were identified by flow cytometry, and differentiation of T helper (Th) lymphocytes was achieved by the relative expression analysis of T-bet (Th1), GATA-3 (Th2), ROR-γ (Th17), and FOXP-3 (T regulatory) transcription factors quantified by real-time PCR. CD8+, CD40L+, and CD45+ cells show higher numbers in DF compared to DHF patients, whereas CD4+, CD19+, and CD25+ cells show higher numbers in DHF than DF patients. High expression of GATA-3 accompanied by low expression of T-bet indicates predominance of Th2 response. In addition, higher expression of FOXP-3 and reduced functional cytotoxic T cells (CD8+perforin+) were observed in DHF patients. In further experiments, PBMC were stimulated ex vivo with dengue virus E, NS3, NS4, and NS5 peptides, and proliferating T cell subsets were determined. Lower proliferative responses to NS3 and NS4 peptides and reduced CD8+ cytotoxic T cells were observed in DHF patients. Our results suggest that immune response to dengue is dysregulated with predominance of CD4+ T cells, low activation of Th1 cells, and downregulation of the antiviral cytotoxic activity during severe dengue, likely induced by regulatory T cells.

Chloroquine Induces ROS-mediated Macrophage Migration Inhibitory Factor Secretion and Epithelial to Mesenchymal Transition in ER-positive Breast Cancer Cell Lines.

Breast cancer (BC) is the leading cause of cancer-related death in women in the world. Since tumor cells employ autophagy as a survival pathway, it has been proposed that autophagy inhibition could be beneficial for cancer treatment. There are several onging clinical trials where autophagy is being inhibited (using chloroquine, CQ or hydroxychloroquine, HCQ) along with chemotherapy with promising results. However, there is also in vitro evidence in which autophagy inhibition can induce epithelial to mesenchymal transition (EMT) in cancer cells, indicating that, at least in some cases, this strategy could be detrimental for cancer patients. In this study, we found that the genetic inhibition of autophagy primed cells for EMT by inducing a decrease in E-cadherin protein levels, while CQ treatment decreased E-cadherin levels, induced morphological changes related to EMT, increased EMT-related transcription factor (EMT-TF) expression and migration in estrogen receptor positive (ER +) BC cell lines. Importantly, CQ treatment increased intracellular reactive oxygen species (ROS) which induced the secretion of macrophage migration inhibitory factor (MIF), a pro-inflammatory cytokine related to malignancy. Both ROS production and MIF secretion were responsible for the mesenchymal morphology and increased migratory capacity induced by CQ. Our results indicate that CQ treatment increased malignancy by inducing ROS production, MIF secretion and EMT and suggest that autophagy inhibition in ER + BC patients might have detrimental effects. Our data indicates that a careful selection of patients should be performed in order to determine who will benefit the most from autophagy inhibition with available pharmacological agents for the treatment of breast cancer.

Patient-Derived Bone Marrow Spheroids Reveal Leukemia-Initiating Cells Supported by Mesenchymal Hypoxic Niches in Pediatric B-ALL.

B-cell acute lymphoblastic leukemia (B-ALL) results from the expansion of malignant lymphoid precursors within the bone marrow (BM), where hematopoietic niches and microenvironmental signals provide leukemia-initiating cells (LICs) the conditions to survive, proliferate, initiate disease, and relapse. Normal and malignant lymphopoiesis are highly dependent on the BM microenvironment, particularly on CXCL12-abundant Reticular (CAR) cells, which provide a niche for maintenance of primitive cells. During B-ALL, leukemic cells hijack BM niches, creating a proinflammatory milieu incompetent to support normal hematopoiesis but favoring leukemic proliferation. Although the lack of a phenotypic stem cell hierarchy is apparent in B-ALL, LICs are a rare and quiescent population potentially responsible for chemoresistance and relapse. Here, we developed novel patient-derived leukemia spheroids (PDLS), an ex vivo avatar model, from mesenchymal stromal cells (MSCs) and primary B-ALL cells, to mimic specialized niche structures and cell-to-cell intercommunication promoting normal and malignant hematopoiesis in pediatric B-ALL. 3D MSC spheroids can recapitulate CAR niche-like hypoxic structures that produce high levels of CXCL10 and CXCL11. We found that PDLS were preferentially enriched with leukemia cells displaying functional properties of LICs, such as quiescence, low reactive oxygen species, drug resistance, high engraftment in immunodeficient mice, and long-term leukemogenesis. Moreover, the combination of PDLS and patient-derived xenografts confirmed a microenvironment-driven hierarchy in their leukemic potential. Importantly, transcriptional profiles of MSC derived from primary patient samples revealed two unique signatures (1), a CXCL12low inflammatory and leukemia expansion (ILE)-like niche, that likely supports leukemic burden, and (2) a CXCL11hi immune-suppressive and leukemia-initiating cell (SLIC)-like niche, where LICs are likely sustained. Interestingly, the CXCL11+ hypoxic zones were recapitulated within the PDLS that are capable of supporting LIC functions. Taken together, we have implemented a novel PDLS system that enriches and supports leukemia cells with stem cell features driven by CXCL11+ MSCs within hypoxic microenvironments capable of recapitulating key features, such as tumor reemergence after exposure to chemotherapy and tumor initiation. This system represents a unique opportunity for designing ex vivo personalized avatars for B-ALL patients to evaluate their own LIC pathobiology and drug sensitivity in the context of the tumor microenvironment.

Hallmarks of glycogene expression and glycosylation pathways in squamous and adenocarcinoma cervical cancer.

BACKGROUND: Dysregulation of glycogene expression in cancer can lead to aberrant glycan expression, which can promote tumorigenesis. Cervical cancer (CC) displays an increased expression of glycogenes involved in sialylation and sialylated glycans. Here, we show a comprehensive analysis of glycogene expression in CC to identify glycogene expression signatures and the possible glycosylation pathways altered. METHODS: First, we performed a microarray expression assay to compare glycogene expression changes between normal and cervical cancer tissues. Second, we used 401 glycogenes to analyze glycogene expression in adenocarcinoma and squamous carcinoma from RNA-seq data at the cBioPortal for Cancer Genomics. RESULTS: The analysis of the microarray expression assay indicated that CC displayed an increase in glycogenes related to GPI-anchored biosynthesis and a decrease in genes associated with chondroitin and dermatan sulfate with respect to normal tissue. Also, the glycogene analysis of CC samples by the RNA-seq showed that the glycogenes involved in the chondroitin and dermatan sulfate pathway were downregulated. Interestingly the adenocarcinoma tumors displayed a unique glycogene expression signature compared to squamous cancer that shows heterogeneous glycogene expression divided into six types. Squamous carcinoma type 5 (SCC-5) showed increased expression of genes implicated in keratan and heparan sulfate synthesis, glycosaminoglycan degradation, ganglio, and globo glycosphingolipid synthesis was related to poorly differentiated tumors and poor survival. Squamous carcinoma type 6 (SCC-6) displayed an increased expression of genes involved in chondroitin/dermatan sulfate synthesis and lacto and neolacto glycosphingolipid synthesis and was associated with nonkeratinizing squamous cancer and good survival. In summary, our study showed that CC tumors are not a uniform entity, and their glycome signatures could be related to different clinicopathological characteristics.

Serum Th17 and TNF-α distinguish between patients with occult hepatitis B infection, chronic hepatitis B infection and healthy individuals.

Chronic hepatitis B (CHB) is classified into five phases based on virus-host interactions: immune tolerance, immune clearance, inactive carrier state, reactive phase and occult hepatitis B infection (OBI). OBI is an uncommon asymptomatic phase of CHB that can be reactivated when the immune system is compromised, occasionally giving rise to severe liver disease. Host immune factors play essential roles in all phases of the CHB infection. Cytokines may alter infection course, influencing the propensity for and the progression of CHB and thus warrant study. Three clinical groups were studied: 48 healthy individuals (HI), 28 patients with persistent positive anti-HBc serological markers and negative HBsAg over time, who were diagnosed as OBI and 12 patients with active CHB. OBI patients were defined by three independent detections of the hepatitis B virus genome through nested PCR and real-time PCR. Quantitative measurement of 20 Th1, Th2 and Th17 human cytokines was performed in the sera of HI, OBI and CHB patients. Levels of IFN-γ, TNF-ß, IL-28A, IL-4, IL-5, IL-13, IL-1ß, IL-6, IL-21, IL-22, IL-23, GM-CSF and MIP-3α were similar between groups. IL-2, IL-12p70, IL-10, IL-17F and TGF-ß1 were similar in HI and OBI, but higher in CHB. TNF-α and the IL-17A:IL-17F ratio were significantly different between the three groups. TNF-α was progressively higher in HI, OBI and CHB (P = 0.004), while the IL-17A:IL-17F ratio was 1.1 in HI, 3.4 in OBI and 0.4 in CHB. Detection and levels of these pro-inflammatory cytokines in OBI patients suggest that they are undergoing a silent hepatic inflammatory process.

SARS-CoV-2: generalidades, origen y avances en el tratamiento / SARS-CoV-2: basic concepts, origin and treatment advances

Resumen Los primeros casos de COVID-19, causada por el virus denominado SARS-CoV-2, se registraron en Wuhan, China, en diciembre de 2019; sin embargo, su capacidad de transmisión ocasionó que seis meses después la infección prácticamente estuviera presente en todo el mundo. El origen del virus parece ser zoonótico; se propone que proviene del murciélago y podría haber tenido un hospedero intermediario que llevó a su introducción en la población humana. SARS-CoV-2 es un virus envuelto, con genoma de ARN de cadena sencilla en sentido positivo y se ancla a la enzima convertidora de angiotensina, presente en las células susceptibles para infectar el sistema respiratorio de los humanos. Aunque previamente se han conocido otros coronavirus, no han tenido el mismo impacto, por lo que la investigación en tratamientos farmacológicos no tiene el desarrollo suficiente para afrontar el reto actual. Casi desde el comienzo de la epidemia se han propuesto moléculas para el tratamiento de la infección, sin embargo, aún no se cuenta con un fármaco con suficiente efectividad terapéutica. En esta revisión se describen las características principales de SARS-CoV-2, su ciclo replicativo, su posible origen y algunos avances en el desarrollo de tratamientos antivirales.

Abstract The first cases of COVID-19, caused by the virus called SARS-CoV-2, were recorded in Wuhan, China, in December 2019; however, its transmission ability caused for the infection to be practically present throughout the world six months later. The origin of the virus appears to be zoonotic; it has been proposed that it comes from a bat and that it may have had an intermediate host that led to its introduction in the human population. SARS-CoV-2 is an enveloped virus, with a positive single-stranded RNA genome, and it binds to the angiotensin-converting enzyme, present in susceptible cells, to infect the human respiratory system. Although other coronaviruses have been previously known, they have not had the same impact, and, therefore, research on pharmacological treatments is not sufficiently developed to face the current challenge. Almost since the beginning of the epidemic, several molecules have been proposed for the treatment of infection; however, there is not yet a drug available with sufficient effectiveness for treatment. This review describes SARS-CoV-2 main characteristics, its replicative cycle, its possible origin and some advances in the development of antiviral treatments.

Glycogene expression profiles from a HaCaT cell line stably transfected with HPV16 E5 oncogene.

The altered expression of glycan antigens has been reported during cervix transformation, demonstrating increased mRNA levels of certain glycogenes. Human papillomavirus (HPV) is the aetiological agent of cervical cancer. High risk HPV E5 is considered an oncogene and has been implicated in cell transformation. E6 and E7 HPV oncoproteins modify the expression of certain glycogenes. The role of the E5 HPV protein in glycogene expression changes has not yet been reported. The aim of the present study was to determine the effects of HPV16 E5 oncoprotein on glycogene expression. For these, a microarray assay was performed using the HaCaT cell line and altered glycogenes were identified. The mRNA levels of certain glycogenes were determined via reverse transcription­quantitative PCR (RT­qPCR). Using in silico analysis, the present study identified that glycosylation pathways were altered by E5. Microarray analysis revealed alterations in certain glycogenes, including the upregulation of ST6GAL1, ST3GAL3, CHST2 and MANBA, and the downregulation of UGT2B15, GALNT11, NDST2 and UGT1A10. Increased mRNA levels were confirmed via RT­qPCR for sialyltransferases genes. Additionally, in silico analysis was performed to identify glycosylation networks altered in the presence of the E5 oncoprotein. The analysis revealed that E5 could modify glycan sialylation, the N­glycosylation pathway, keratan sulfate and glycosaminoglycan synthesis. To the best of our knowledge, the current study was the first to determine the role of the HPV16 E5 oncoprotein in glycogene expression changes. The results indicated that increased sialyltransferase mRNA levels reported in pre­malignant and malignant cervical tissues could be the result of E5 oncoprotein expression. The results provide a possible role of HPV infection on glycosylation changes reported during cervix transformation.

MOLECULAR MARKERS FOR THE DIAGNOSIS OF HIGH-RISK HUMAN PAPILLOMAVIRUS INFECTION AND TRIAGE OF HUMAN PAPILLOMAVIRUS-POSITIVE WOMEN.

Infection with high-risk human papillomavirus (HPV) increases the likelihood of developing cervical cancer (CC). A plethora of cellular processes is required to produce pre-malignant lesions, which in turn may become malignant if left untreated. Those changes are induced by viral oncoproteins, which represent an ideal target to identify the viral presence, or by some particularities of the host that ultimately promote the establishment of CC. This article describes the different methods used for HPV detection and quantification, as well as the current trend of secondary screening approaches to detect premalignant lesions and CC. In addition, we analyzed validated biomarkers and those under clinical investigation for the classification (triage) of women at risk of developing CC after an initial positive HPV test and that could be used as prognostic biomarkers for CC. The use of molecular biomarkers, together with the detection of HPV DNA sequences, provides a high impact diagnostic and prognostic tool in the detection of patients at increased risk of developing CC and also may guide their clinical management. In addition, some of those biomarkers could represent pharmacological targets for the future design of therapeutic approaches to CC treatment.

Histone H3K9 and H3K14 acetylation at the promoter of the LGALS9 gene is associated with mRNA levels in cervical cancer cells.

Galectin-9 levels have been reported to be altered in several cancer types, but the mechanism that regulates the expression of Galectin-9 has not been clarified. Galectin-9 is encoded by the LGALS9 gene, which gives rise to eight mRNA variants. The aims of this study were: (a) to identify the mRNA variants of LGALS9, (b) to characterize CpG methylation and H3K9 and H3K14 histone acetylation at the promoter of the LGALS9 gene, and (c) to characterize the relationship between these modifications and LGALS9 expression level in cervical cancer cells. All mRNA variants were detected in HaCaT (nontumoural keratinocytes) and SiHa cells, and seven were observed in HeLa cells. The promoter region of LGALS9 contains eight CpG dinucleotides. No hypermethylation pattern related to low LGALS9 expression was identified in tumour cells. Chromatin immunoprecipitation analysis demonstrated higher acetylation of H3K9ac and H3K14ac in HaCaT cells, which was related to higher mRNA levels. The presence of the mRNA variants suggests that alternative splicing may regulate the expression of galectin-9 isoforms. The results of this study suggest that histone acetylation, but not promoter CpG methylation, may be involved in the transcriptional regulation of the LGALS9 gene.

Molecular markers for the diagnosis of high-risk human papillomavirus infection and triage of human papillomavirus-positive women

ABSTRACT Infection with high-risk human papillomavirus (HPV) increases the likelihood of developing cervical cancer (CC). A plethora of cellular processes is required to produce pre-malignant lesions, which in turn may become malignant if left untreated. Those changes are induced by viral oncoproteins, which represent an ideal target to identify the viral presence, or by some particularities of the host that ultimately promote the establishment of CC. This article describes the different methods used for HPV detection and quantification, as well as the current trend of secondary screening approaches to detect premalignant lesions and CC. In addition, we analyzed validated biomarkers and those under clinical investigation for the classification (triage) of women at risk of developing CC after an initial positive HPV test and that could be used as prognostic biomarkers for CC. The use of molecular biomarkers, together with the detection of HPV DNA sequences, provides a high impact diagnostic and prognostic tool in the detection of patients at increased risk of developing CC and also may guide their clinical management. In addition, some of those biomarkers could represent pharmacological targets for the future design of therapeutic approaches to CC treatment.