The Human Papillomavirus (HPV) E1 protein is the only viral protein with enzymatic activity. The main known function of this protein is the regulation of the viral DNA replication. Nevertheless, it has been demonstrated that the ablation of HPV18 E1 mRNA in HeLa cells promotes a deregulation of several genes, particularly those involved in host defense mechanisms against viral infections; however, the specific contribution of E1 protein in HPV-independent context has not been studied. The aim of this work was to determine the effect of the HPV E1 protein in the regulation of cellular gene expression profiles evaluated through RNA-seq. We found that E1 proteins from HPV16 and 18 induced an overexpression of different set of genes associated with proliferation and differentiation processes, as well as downregulation of immune response genes, including IFNβ1 and IFNλ1 and Interferon-stimulated gene (ISG), which are important components involved in the antiviral immune response. Together, our results indicate that HR-(High-Risk) and LR-(Low-Risk) HPV E1 proteins play an important role in inhibiting the anti-viral immune response.
Breast cancer is the most commonly diagnosed neoplasm in women worldwide with a well-recognized heterogeneous pathology, classified into four molecular subtypes: Luminal A, Luminal B, HER2-enriched and Basal-like, each one with different biological and clinical characteristics. Long non-coding RNAs (lncRNAs) represent 33% of the human transcriptome and play critical roles in breast carcinogenesis, but most of their functions are still unknown. Therefore, cancer research could benefit from continued exploration into the biology of lncRNAs in this neoplasm. We characterized lncRNA expression portraits in 74 breast tumors belonging to the four molecular subtypes using transcriptome microarrays. To infer the biological role of the deregulated lncRNAs in the molecular subtypes, we performed co-expression analysis of lncRNA–mRNA and gene ontology analysis. We identified 307 deregulated lncRNAs in tumor compared to normal tissue and 354 deregulated lncRNAs among the different molecular subtypes. Through co-expression analysis between lncRNAs and protein-coding genes, along with gene enrichment analysis, we inferred the potential function of the most deregulated lncRNAs in each molecular subtype, and independently validated our results taking advantage of TCGA data. Overexpression of the AC009283.1 was observed in the HER2-enriched subtype and it is localized in an amplification zone at chromosome 17q12, suggesting it to be a potential tumorigenic lncRNA. The functional role of lncRNA AC009283.1 was examined through loss of function assays in vitro and determining its impact on global gene expression. These studies revealed that AC009283.1 regulates genes involved in proliferation, cell cycle and apoptosis in a HER2 cellular model. We further confirmed these findings through ssGSEA and CEMITool analysis in an independent HER2-amplified breast cancer cohort. Our findings suggest a wide range of biological functions for lncRNAs in each breast cancer molecular subtype and provide a basis for their biological and functional study, as was conducted for AC009283.1, showing it to be a potential regulator of proliferation and apoptosis in the HER2-enriched subtype.
The SARS-CoV-2 pandemic is one of the most concerning health problems around the globe. We reported the emergence of SARS-CoV-2 variant B.1.1.519 in Mexico City. We reported the effective reproduction number (Rt) of B.1.1.519 and presented evidence of its geographical origin based on phylogenetic analysis. We also studied its evolution via haplotype analysis and identified the most recurrent haplotypes. Finally, we studied the clinical impact of B.1.1.519. The B.1.1.519 variant was predominant between November 2020 and May 2021, reaching 90% of all cases sequenced in February 2021. It is characterized by three amino acid changes in the spike protein: T478K, P681H, and T732A. Its Rt varies between 0.5 and 2.9. Its geographical origin remain to be investigated. Patients infected with variant B.1.1.519 showed a highly significant adjusted odds ratio (aOR) increase of 1.85 over non-B.1.1.519 patients for developing a severe/critical outcome (p = 0.000296, 1.33–2.6 95% CI) and a 2.35-fold increase for hospitalization (p = 0.005, 1.32–4.34 95% CI). The continuous monitoring of this and other variants will be required to control the ongoing pandemic as it evolves.
Cancer represents a complex disease originated from alterations in several genes leading to the disturbances of important signaling pathways in tumor biology favoring heterogeneity that promotes adaptability and pharmacological resistance of tumor cells. Metabolic reprogramming has emerged as an important hallmark of cancer characterized by the presence of aerobic glycolysis, increased glutaminolysis and fatty acid biosynthesis, as well as an altered mitochondrial energy production. The metabolic switches that support energetic requirements of cancer cells are closely related to either activation of oncogenes or down-modulation of tumor-suppressor genes, finally leading to dysregulation of cell proliferation, metastasis and drug resistance signals. Non coding RNAs (ncRNAs) have emerged as one important kind of regulatory molecules of the altered genes contributing to the establishment of metabolic reprogramming. Moreover, diverse metabolic signals can regulate ncRNAs expression and activity at genetic, transcriptional or epigenetic level. The regulatory landscape of ncRNAs may provide a new approach for understanding and treatment of different kind of malignancies. In this review we discuss the regulatory role exerted by ncRNAs on metabolic enzymes and pathways involved in glucose, lipid and amino acid metabolism. We also review how the metabolic stress conditions and tumoral microenvironment influence ncRNA expression and activity. Furthermore, we comment the therapeutic potential of metabolism-related ncRNAs in cancer.
Triple negative breast cancer (TNBC) represents an aggressive phenotype with poor prognosis compared with ER, PR, and HER2‐positive tumors. TNBC is a heterogeneous disease, and gene expression analysis has identified seven molecular subtypes. Accumulating evidence demonstrates that long non‐coding RNA (lncRNA) are involved in regulation of gene expression and cancer biology, contributing to essential cancer cell functions. In this study, we analyzed the expression profile of lncRNA in TNBC subtypes from 156 TNBC samples, and then characterized the functional role of LncKLHDC7B (ENSG00000226738). A total of 710 lncRNA were found to be differentially expressed between TNBC subtypes, and a subset of these altered lncRNA were independently validated. We discovered that LncKLHDC7B (ENSG00000226738) acts as a transcriptional modulator of its neighboring coding gene KLHDC7B in the immunomodulatory subtype. Furthermore, LncKLHDC7B knockdown enhanced migration and invasion, and promoted resistance to cellular death. Our findings confirmed the contribution of LncKLHDC7B to induction of apoptosis and inhibition of cell migration and invasion, suggesting that TNBC tumors with enrichment of LncKLHDC7B may exhibit distinct regulatory activity, or that this may be a generalized process in breast cancer. Additionally, in silico analysis confirmed for the first time that the low expression of KLHDC7B and LncKLHDC7B is associated with poor prognosis in patients with breast cancer.