Publications by authors named "Luis Marat Alvarez-Salas"

MicroRNAs (miRNAs) are small non-coding RNAs (ncRNAs) that negatively regulate gene expression. MiRNAs regulate fundamental biological processes and have significant roles in several pathologies, including cancer. Cervical cancer is the best-known example of a widespread human malignancy with a demonstrated viral etiology.

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Cancer is a disease with the highest mortality and morbidity rate worldwide. First-line drugs induce several side effects that drastically reduce the quality of life of people with this disease. Finding molecules to prevent it or generate less aggressiveness or no side effects is significant to counteract this problem.

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The proximal tubule is a target of subchronic exposure to fluoride (F) in the kidney. Early markers are used to classify kidney damage, stage, and prognosis. MicroRNAs (miRNAs) are small sequences of non-coding single-stranded RNA that regulate gene expression and play an essential role in developing many pathologies, including renal diseases.

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The COVID-19 pandemic has been a main concern over the last two years and has become one of the most important crises in the history of human health. Today, there is still a need for affordable and reliable diagnostic tests for massive disease monitoring. Previously, a set of highly specific DNA-aptamers (C7/C9) binding to the SARS-CoV-2 Spike (S) protein were isolated but its performance in clinical samples remained to be tested.

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The spontaneous interaction between human papillomavirus type 16 (HPV16) L1 virus-like particles (VLPs) and non-functionalized gold nanoparticles (nfGNPs) interferes with the nfGNPs' salt-induced aggregation, inhibiting the red-blue color shift in the presence of NaCl. Electron microscopy and competition studies showed that color-shift inhibition is a consequence of direct nfGNP-VLP interaction and, thus, may produce a negative impact on the virus entry cell process. Here, an in vitro infection system based on the HPV16 pseudovirus (PsV) was used to stimulate the natural infection process in vitro.

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Cervical cancer is the leading cause of death by cancer in women from developing countries. Persistent infection with high-risk human papillomavirus (HPV) types 16 and 18 is a major risk factor for cervical carcinogenesis. Nevertheless, only a few women with morphologic expression of HPV infection progress into invasive disease suggesting the involvement of other factors in cervical carcinogenesis.

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ZO-2 is a peripheral ight unction (TJ) protein whose silencing in renal epithelia induces cell hypertrophy. Here, we found that in ZO-2 KD MDCK cells, in compensatory renal hypertrophy triggered in rats by a unilateral nephrectomy and in liver steatosis of bese ucker (OZ) rats, ZO-2 silencing is accompanied by the diminished activity of LATS, a kinase of the Hippo pathway, and the nuclear concentration of YAP, the final effector of this signaling route. ZO-2 appears to function as a scaffold for the Hippo pathway as it associates to LATS1.

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The main treatment alternative for cervical cancer is cisplatin chemotherapy. However, the resistance of tumor cells to cisplatin, in addition to side effects, limits its use. The flavonoid naringenin has shown cytotoxic effects on tumor cells and may be considered as a coadjuvant in the treatment of cervical cancer.

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The Let-7:LIN28 regulatory loop is a paradigm in miRNA regulation. LIN28 harbors two RNA binding domains, which interact with well-conserved sequences in pre-let-7 RNAs, the GNGAY and the GGAG motifs. Here, the differential binding between LIN28B and pre-let-7 members was associated with the structural characteristics of the pre-let-7 family mapped by SHAPE, uncovering diverse structural patterns within pre-let-7 members.

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The miR-143/145 cluster is down-regulated in cervical tumor cells suggesting a role in tumorigenesis including cytoskeleton remodeling, a key event for tumor progression. The aim of the present work was to determine the role of miR-143/145 in the modulation of the myosin regulator phospho-myosin light chain (pMLC). HeLa monolayer and tridimensional cultures were transfected with miR-143 or miR-145 mimics inhibiting cell viability, proliferation, migration and invasion, mainly through miR-145.

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Preterm birth is the leading cause of neonatal morbidity and mortality worldwide. Inflammation is causally linked to preterm birth; therefore, finding an intervention that dampens maternal and fetal inflammatory responses may provide a new strategy to prevent adverse pregnancy and neonatal outcomes. Using animal models of systemic maternal inflammation [intraperitoneal injection of lipopolysaccharide (LPS)] and fetal inflammation (intra-amniotic administration of LPS), we found that (1) systemic inflammation induced adverse pregnancy and neonatal outcomes by causing a severe maternal cytokine storm and a mild fetal cytokine response; (2) fetal inflammation induced adverse pregnancy and neonatal outcomes by causing a mild maternal cytokine response and a severe fetal cytokine storm; (3) exendin-4 (Ex4) treatment of dams with systemic inflammation or fetal inflammation improved adverse pregnancy outcomes by modestly reducing the rate of preterm birth; (4) Ex4 treatment of dams with systemic, but not local, inflammation considerably improved neonatal outcomes, and such neonates continued to thrive; (5) systemic inflammation facilitated the diffusion of Ex4 through the uterus and the maternal-fetal interface; (6) neonates born to Ex4-treated dams with systemic inflammation displayed a similar cytokine profile to healthy control neonates; and (7) treatment with Ex4 had immunomodulatory effects by inducing an M2 macrophage polarization and increasing anti-inflammatory neutrophils, as well as suppressing the expansion of CD8+ regulatory T cells, in neonates born to dams with systemic inflammation.

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Human papillomavirus type 16 (HPV16) DNA has been found in ∼50% of cervical tumors worldwide. HPV infection starts with the binding of the virus capsid to heparan sulfate (HS) receptors exposed on the surface of epithelial basal layer keratinocytes. Previously, our group isolated a high-affinity RNA aptamer (Sc5c3) specific for HPV16 L1 virus-like particles (VLPs).

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Background: The let-7 microRNAs (miRNAs) are frequently dysregulated in carcinogenic processes, including cervical cancer. LIN28 proteins regulate let-7 biogenesis by binding to conserved sequences within the pre-miRNA structure. Nevertheless, recent research has shown that some let-7 miRNAs may escape LIN28 regulation.

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Background: Aberrant miRNA expression is associated with the development of several diseases including cervical cancer. Dysregulation of miR-125a-5p is present in a plethora of tumors, but its role in cervical cancer is not well understood.

Objective: The aim was to analyze the expression profile of miR-125a-5p in tumor and immortal cell lines with further target prediction, validation and function analysis.

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Colorimetric assays based on gold nanoparticles (GNPs) are of considerable interest for diagnostics because of their simplicity and low-cost. Nevertheless, a deep understanding of the interaction between the GNPs and the intended molecular target is critical for the development of reliable detection technologies. The present report describes the spontaneous interaction between HPV16 L1 virus-like particles (VLPs) and non-functionalized GNPs (nfGNPs) resulting in the inhibition of nfGNPs salt-induced aggregation and the stabilization of purified VLPs.

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The expression of high-risk human papillomavirus E6 and E7 proteins in most cervical tumors raised a considerable interest in the diagnostic and therapeutic applications of functional oligonucleotides (i.e., DNAzymes, ribozymes, and aptamers) directed against HPV targets.

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The human papillomavirus (HPV) capsid is mainly composed of the L1 protein that can self-assemble into virus-like particles (VLPs) that are structurally and immunologically similar to the infectious virions. We report here the characterization of RNA aptamers that recognize baculovirus-produced HPV-16 L1 VLPs. Interaction and slot-blot binding assays showed that all isolated aptamers efficiently bound HPV-16 VLPs, although the Sc5-c3 aptamer showed the highest specificity and affinity (Kd=0.

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Deoxyribozymes (DXZs) are catalytic oligodeoxynucleotides capable of performing diverse functions including the specific cleavage of a target RNA. These molecules represent a new type of therapeutic oligonucleotides combining the efficiency of ribozymes and the intracellular endurance and simplicity of modified antisense oligonucleotides. Commonly used DXZs include the 8-17 and 10-23 motifs, which have been engineered to destroy disease-associated genes with remarkable efficiency.

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MicroRNAs (miRNA) regulate expression of several genes associated with human cancer. Here, we analyzed the function of miR-34c, an effector of p53, in cervical carcinoma cells. Expression of either miR-34c-3p or miR-34c-5p mimics caused inhibition of cell proliferation in the HPV-containing SiHa cells but not in other cervical cells irrespective of tumorigenicity and HPV content.

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Triplex ribozymes allow for the individual activity of multiple trans-acting ribozymes producing higher target cleavage relative to tandem-expressed RZs. A triplex expression system based on a single hairpin ribozyme for the multiple expression (multiplex) vectors can be engineered to target RNAs with single or multiple antisense-accessible sites. System construction relies on triplex expression modules consisting of hairpin ribozyme cassettes flanked by ribozymes lacking catalytic domains.

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