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Gastric cancer (GC) is worldwide the sixth most diagnosed and third leading cause of cancer deaths, with poor and late prognosis, probably due to post-surgery adjuvant treatment resistance and lack of a thorough panel of prognostic markers. We have previously shown that mitotic arrest deficient 2 (MAD2, encoded by MAD2L1), a key protein of the spindle assembly checkpoint, is relevant in GC cells; its interference impairs migration and growth, while its overexpression correlates with tumorigenesis.1 Here we show a similar correlation with overall survival (OS) in a pilot patient series. We hypothesized that MAD2 overexpression might relate to micro-RNA (miRNA) deregulation. Bioinformatic analysis identified miRNAs specifically targeting MAD2L1-3′UTR. Expression of miR-19a and miR-203 inversely correlated with MAD2L1 expression in GC cell lines and patients' samples. A broader analysis using Cancer Genome Atlas data showed that only high miR-19 levels correlated with a better OS, especially in patients overexpressing MAD2L1. In GC cells, miR-19a expression reduced cell migration and invasion capability and increased apoptosis, in combination with classical and new antitumoral drugs. We propose that miR-19a is a critical regulator of MAD2 protein in GC, with potential clinical use as a prognostic biomarker, and as a model for MAD2 interfering agent design with therapeutical potential.

Thermal deposition of laser energy in the vaginal epithelium in genitourinary syndrome of menopause (GSM) results in clinical and biological effects, but many cellular and molecular changes indicating cell proliferation or senescence inhibition are unknown. The aim of this study is to evaluate the clinical efficacy of the fractional-pixel-CO2 laser in the possible improvement of GMS signs and symptoms that can be correlated with histological changes or with cellular or molecular indicators of restoration. A detailed prospective study was designed to assess 17 women diagnosed with GSM who were treated intravaginally with two laser sessions. Seven non-treated women diagnosed with GSM were used as controls. Three validated outcome questionnaires for assessment of quality of sexual life and urinary incontinence were performed. Vaginal biopsies were collected before the first laser treatment and 4 months following the second session. Histological status, elastin, collagen, and hyaluronic acid content of the biopsies were also evaluated. Cell proliferation was assessed by Ki67 staining. Telomere length (TL) was measured by qPCR. The results show an improvement of the clinical symptoms of GSM (p < 0.05), vaginal epithelium recovery and enhancement of collagen (p < 0.05), elastic fibers (p < 0.005), and hyaluronic acid (p < 0.0005) content in the lamina propria after fractional-pixel-CO2 laser treatment. The laser treatment induced a significant rise on the TL of vaginal epithelial cells (VECs), and a positive correlation was found between the improvements of the collagen and hyaluronic acid content and TL changes (r = 0.82, p < 0.05; r = 0.38, p < 0.05). The percentage of proliferative Ki67-positive VECs was increased in patients whose vaginal TL lengthened after laser treatment (p < 0.05). In conclusion, the results indicate that laser treatment may induce restoration of the vaginal epithelium which is associated to increased TL and proliferation in the VECs. Performing a

Colorectal cancer is the second most common cancer in women, the third in men, and an important cause of cancer-related mortality. Recurrence and the development of chemotherapy resistance are major hindrances for patients’ treatment. The presence of cancer stem cells with chemotherapy resistance able to generate proliferating tumor cells contributes to tumor recurrence and resistance. In addition, tumor cells can develop chemoresistance through adaptation mechanisms. In this article, cancer stem cells were isolated from HT29 and SW620 colorectal cancer cell lines. Oxaliplatin resistance was induced by a single drug treatment simulating the usual guidelines of patient treatment. A comparison of these two populations showed similarities since cancer stem cells presented increased oxaliplatin resistance, and resistant cells contained an increased number of cancer stem cells. Cancer stem cells isolated from resistant cells showed increased oxaliplatin resistance. Cell invasion capacity and epithelial-mesenchymal transition were increased both in cancer stem cells and oxaliplatin-resistant cells. mRNA expression analysis showed that both cell types shared a significant proportion of commonly regulated genes. In summary, the data presented indicate that colorectal cancer stem cells and oxaliplatin-resistant cells are highly related cell populations that might have interesting implications in the development of tumor recurrence and resistance to chemotherapy.

CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research.

Background Age and comorbidity are the main determinants of COVID-19 outcome. Shorter leukocyte telomere length (TL), a hallmark of biological aging, has been associated with worse COVID-19 outcomes. We sought to determine TL in patients with severe COVID-19 requiring hospitalization to analyze whether clinical outcomes and post-COVID-19 manifestations are associated with shorter TL. Results We analyzed 251 patients with PCR-confirmed COVID-19, hospitalized in the first months of the pandemics. We determined TL in PBL at admission by quantitative-PCR (qPCR) analysis in patients. A healthy cohort from the same area with a similar age range (n = 169) was used to calculate TL Z-scores. After hospital discharge, 144 COVID-19 survivors were followed-up for persistent COVID-19 manifestations. A second TL determination was performed in a smaller group of 63 patients 1 year later and compared with baseline TL. Hospitalized COVID-19 patients had a decreased baseline age-adjusted TL Z-score compared to the reference group. No differences in Z-scores were observed in patients with different COVID-19 outcomes, classified as WHO ordinal scores. In 144 patients, followed for a median of 8 months, post-COVID manifestations were not associated to differences in TL. Persistence of lung radiographic abnormalities was associated with shorter baseline TL. In patients with a second TL determination, further telomere shortening (TS) was observed in 35% and telomere lengthening in 49%. Patients with further TS had suffered a more severe disease. Conclusion Shorter TL is associated with COVID-19 hospitalization but not with hospital clinical outcomes nor with persistent post-COVID-19 manifestations. Delayed resolution of radiographic lung abnormalities was also associated with shorter TL.

Cross-analysis of clinical and pollution factors could help calculate the risk of fibrotic interstitial lung disease (ILD) development and progression. The intent of this study is to build a body of knowledge around early detection and diagnosis of lung disease, harnessing new data sets generated for other purposes. We cross-referenced exposure levels to particulate matter 2.5 (PM2.5) with telomere length of a cohort of 280 patients with fibrotic ILD to weigh impact and associations. There was no linear correlation between PM2.5 and telomere length in our data sets, as the value of the correlation coefficient was 0.08. This exploratory study offers additional insights into methodologies for investigating the development and prognosis of pulmonary fibrosis.

Idiopathic pulmonary fibrosis is a lethal lung fibrotic disease, associated with aging with a mean survival of 2-5 years and no curative treatment. The GSE4 peptide is able to rescue cells from senescence, DNA and oxidative damage, inflammation, and induces telomerase activity. Here, we investigated the protective effect of GSE4 expression in vitro in rat alveolar epithelial cells (AECs), and in vivo in a bleomycin model of lung fibrosis. Bleomycin-injured rat AECs, expressing GSE4 or treated with GSE4-PLGA/PEI nanoparticles showed an increase of telomerase activity, decreased DNA damage, and decreased expression of IL6 and cleaved-caspase 3. In addition, these cells showed an inhibition in expression of fibrotic markers induced by TGF-beta such as collagen-I and III among others. Furthermore, treatment with GSE4-PLGA/PEI nanoparticles in a rat model of bleomycin-induced fibrosis, increased telomerase activity and decreased DNA damage in proSP-C cells. Both in preventive and therapeutic protocols GSE4-PLGA/PEI nanoparticles prevented and attenuated lung damage monitored by SPECT-CT and inhibited collagen deposition. Lungs of rats treated with bleomycin and GSE4-PLGA/PEI nanoparticles showed reduced expression of alpha-SMA and pro-inflammatory cytokines, increased number of pro-SPC-multicellular structures and increased DNA synthesis in proSP-C cells, indicating therapeutic efficacy of GSE4-nanoparticles in experimental lung fibrosis and a possible curative treatment for lung fibrotic patients

Inherited bone marrow failure syndromes (IBMFSs) are a group of congenital rare diseases characterized by bone marrow failure, congenital anomalies, high genetic heterogeneity, and predisposition to cancer. Appropriate treatment and cancer surveillance ideally depend on the identification of the mutated gene. A next-generation sequencing (NGS) panel of genes could be 1 initial genetic screening test to be carried out in a comprehensive study of IBMFSs, allowing molecular detection in affected patients. We designed 2 NGS panels of IBMFS genes: version 1 included 129 genes and version 2 involved 145 genes. The cohort included a total of 204 patients with suspected IBMFSs without molecular diagnosis. Capture-based targeted sequencing covered > 99% of the target regions of 145 genes, with more than 20 independent reads. No differences were seen between the 2 versions of the panel. The NGS tool allowed a total of 91 patients to be diagnosed, with an overall molecular diagnostic rate of 44%. Among the 167 patients with classified IBMFSs, 81 patients (48%) were diagnosed. Unclassified IBMFSs involved a total of 37 patients, of whom 9 patients (24%) were diagnosed. The preexisting diagnosis of 6 clinically classified patients (6%) was amended, implying a change of therapy for some of them. Our NGS IBMFS gene panel assay is a useful tool in the molecular diagnosis of IBMFSs and a reasonable option as the first tier genetic test in these disorders.

Dyskeratosis congenita (DC) is a rare telomere biology disorder, which results in different clinical manifestations, including severe bone marrow failure. To date, the only curative treatment for the bone marrow failure in DC patients is allogeneic hematopoietic stem cell transplantation. However, due to the toxicity associated to this treatment, improved therapies are recommended for DC patients. Here, we aimed at generating DC-like human hematopoietic stem cells in which the efficacy of innovative therapies could be investigated. Because X-linked DC is the most frequent form of the disease and is associated with an impaired expression of DKC1, we have generated DC-like hematopoietic stem cells based on the stable knock-down of DKC1 in human CD34+ cells with lentiviral vectors encoding for DKC1 short hairpin RNAs. At a molecular level, DKC1-interfered CD34+ cells showed a decreased expression of TERC, as well as a diminished telomerase activity and increased DNA damage, cell senescence, and apoptosis. Moreover, DKC1-interfered human CD34+ cells showed defective clonogenic ability and were incapable of repopulating the hematopoiesis of immunodeficient NSG mice. The development of DC-like hematopoietic stem cells will facilitate the understanding of the molecular and cellular basis of this inherited bone marrow failure syndrome and will serve as a platform to evaluate the efficacy of new hematopoietic therapies for DC.

La presente invención se refiere a un polipéptido que comprende elfragmento SEQ ID No.: 2 del péptido GSE24.2 (SEQ ID No.:1) y escapaz de disminuir la producción de radicales libres y/o el daño en la estructura del ADN de una célula, pudiendo opcionalmente comprender secuencias de localización nuclear.Además, la invención también se refiere a un polinucleótido y a un vector, los cuales comprenden secuencias que codifican dicho polipéptido, así como a una composición farmacéutica que comprenda el polipéptido, polinucleótido y/o vector anteriores. La presente invención también hace referencia a las aplicaciones del polipéptido, como son el uso para tratar y/o prevenir enfermedades provocadas por aumento del estrés oxidativo y/o del daño del ADN celular, tales como la ataxia telangectasia o la disqueratosis congénita, o el uso en ingeniería de tejidos y cultivo celular para mejorar la viabilidad de los mismos. [ES], The invention relates to a polypeptide which comprises the fragment SEQ ID No.: 2 of the peptide GSE 24.2 (SEQ ID No.:1) and can reduce the production of free radicals and/or damage to the DNA structure of a cell, optionally comprising nuclear localisation sequences. The invention also relates to a polynucleotide and to a vector, which comprise sequences coding for said polypeptide, and to a pharmaceutical composition comprising said polypeptide, polynucleotide and/or vector. The invention further relates to the applications of the polypeptide, such as the use thereof for treating and/or preventing diseases caused by an increase in oxidative stress and/or damage to cellular DNA, such as ataxia-telangiectasia or dyskeratosis congenita, or the use thereof in tissue engineering and cell culture for increasing the viability of same. [EN]

The ‘cancer cell fusion’ theory is controversial due to the lack of methods available to identify hybrid cells and to follow the phenomenon in patients. However, it seems to be one of the best explanations for both the origin and metastasis of primary tumors. Herein, we co-cultured lung cancer stem cells with human monocytes and analyzed the dynamics and properties of tumor-hybrid cells (THC), as well as the molecular mechanisms beneath this fusion process by several techniques: electron-microscopy, karyotyping, CRISPR-Cas9, RNA-seq, immunostaining, signaling blockage, among others. Moreover, mice models were assessed for in vivo characterization of hybrids colonization and invasiveness. Then, the presence of THCs in bloodstream and samples from primary and metastatic lesions were detected by FACS and immunofluorescence protocols, and their correlations with TNM stages established. Our data indicate that the generation of THCs depends on the expression of CD36 on tumor stem cells and the oxidative state and polarization of monocytes, the latter being strongly influenced by microenvironmental fluctuations. Highly oxidized M2-like monocytes show the strongest affinity to fuse with tumor stem cells. THCs are able to proliferate, colonize and invade organs. THC-specific cell surface signature CD36+CD14+PANK+ allows identifying them in matched primary tumor tissues and metastases as well as in bloodstream from patients with lung cancer, thus functioning as a biomarker. THCs levels in circulation correlate with TNM classification. Our results suggest that THCs are involved in both origin and spread of metastatic cells. Furthermore, they might set the bases for future therapies to avoid or eradicate lung cancer metastasis.

Mitogen-activated protein kinases (MAPK) p38 and c-Jun N-terminal kinases (JNKs) are activated during the cellular response to stress signals. Their activity is regulated by the MAPK-phosphatase 1 (DUSP1), a key component of the anti-inflammatory response. Stress kinases are well-described elements of the response to otic injury and the otoprotective potential of JNK inhibitors is being tested in clinical trials. In contrast, there are no studies exploring the role of DUSP1 in hearing and hearing loss. Here we show that Dusp1 expression is age-regulated in the mouse cochlea. Dusp1 gene knock-out caused premature progressive hearing loss, as confirmed by auditory evoked responses in Dusp1-/- mice. Hearing loss correlated with cell death in hair cells, degeneration of spiral neurons and increased macrophage infiltration. Dusp1-/- mouse cochleae showed imbalanced redox status and deregulated expression of cytokines. These data suggest that DUSP1 is essential for cochlear homeostasis in the response to stress during ageing.

La presente invención se refiere a un método para predecir la respuesta al tratamiento con radioterapia combinada con quimioterapia basada en cisplatino en pacientes con cáncer, preferiblemente cáncer de pulmón no microcítico, donde dicho método se basa en la detección de la presencia de metilación del gen IGFBP-3. Por tanto, la invención se podría encuadrar en el campo del tratamiento del cáncer

The Werner syndrome is a segmental progeroid syndrome of adult onset characterized by the presence of multiple features resembling accelerated aging accompanied by rare tumors. Commonly, the first symptom is the lack of growth spurt during one’s teens. Later on, WS patients have an aged appearance and early onset of age-related disorders; Werner’s syndrome is a rare disease caused by biallelic mutations in the WRN gene.

Is a rare disease originally defined by a triad of mucocutaneous features: leukoplakia, reticulated skin pigmentation (observed at neck and upper chest), and nail dystrophy. Now is known to be a telomerase-defective disease with premature aging symptoms in different tissues (See “Aging Mechanisms” and “Aging Pathology”).

Telomeres are nucleo-protein structures that protect the ends of eukaryotic chromosomes. They are not completely synthesized during DNA replication and are elongated by specific mechanisms. The structure of the telomeres and the elongation mechanism have not been determined in Dictyostelium discoideum. This organism presents extrachromosomal palindromic elements containing two copies of the rDNA, also present at the end of the chromosomes. In this article the structure of the terminal region of the rDNA is shown to consist of repetitions of the A(G)n sequence where the number of Gs is variable. These repeats extend as a 3' single stranded region. The G-rich region is preceded by four tandem repetitions of two different DNA motifs. D. discoideum telomere reverse transcriptase homologous protein (TERTHP) presented RNase-sensitive enzymatic activity and was required to maintain telomere structure since terthp-mutant strains presented reorganizations of the DNA terminal regions. These modifications were different in several terthp-mutants and changed with their prolonged culture and subcloning. However, the terthp gene is not essential for D. discoideum proliferation. Telomeres could be maintained in terthp-mutant strains by homologous recombination mechanisms such as ALT (Alternative Lengthening of Telomeres) or HAATI (heterochromatin amplification-mediated and telomerase-independent). In agreement with this hypothesis, the expression of mRNAs coding for several proteins involved in homologous recombination was induced in terthp-mutant strains. Extrachromosomal rDNA could serve as substrate in these DNA homologous recombination reactions.

Reduction of caloric intake delays and prevents age-associated diseases and extends the life span in many organisms. It may be that these benefits are due to positive effects of caloric restriction on stem cell function. We use the planarian model Schmidtea mediterranea, an immortal animal that adapts to long periods of starvation by shrinking in size, to investigate the effects of starvation on telomere length. We show that the longest telomeres are a general signature of planarian adult stem cells. We also observe that starvation leads to an enrichment of stem cells with the longest telomeres and that this enrichment is dependent on mTOR signaling. We propose that one important effect of starvation for the rejuvenation of the adult stem cell pool is through increasing the median telomere length in somatic stem cells. Such a mechanism has broad implications for how dietary effects on aging are mediated at the whole-organism level. González-Estévez and colleagues show that long telomeres are a signature of planarian stem cells. They find that in the immortal planarian, starvation leads to an enrichment of stem cells with the longest telomeres dependent on mTOR signaling. They propose that starvation contributes to the rejuvenation of the adult stem cell pool by increasing their telomere length.

Dyskerin is a protein involved in the formation of small nucleolar and small Cajal body ribonucleoproteins. These complexes participate in RNA pseudouridylation and are also components of the telomerase complex required for telomere elongation. Dyskerin mutations cause a rare disease, X-linked dyskeratosis congenita, with no curative treatment. The social amoeba Dictyostelium discoideum contains a gene coding for a dyskerin homologous protein. In this article D. discoideum mutant strains that have mutations corresponding to mutations found in dyskeratosis congenita patients are described. The phenotype of the mutant strains has been studied and no alterations were observed in pseudouridylation activity and telomere structure. Mutant strains showed increased proliferation on liquid culture but reduced growth feeding on bacteria. The results obtained indicated the existence of increased DNA damage response and reactive oxygen species, as also reported in human Dyskeratosis congenita cells and some other disease models. These data, together with the haploid character of D. discoideum vegetative cells, that resemble the genomic structure of the human dyskerin gene, located in the X chromosome, support the conclusion that D. discoideum can be a good model system for the study of this disease.

Vascular complications such as bleeding due to gastrointestinal telangiectatic anomalies, pulmonary arteriovenous malformations, hepatopulmonary syndrome, and retinal vessel abnormalities are being reported in patients with telomere biology disorders (TBDs) more frequently than previously described. The international clinical care consortium of telomere-associated ailments and family support group Dyskeratosis Congenita Outreach, Inc. held a workshop on vascular abnormalities in the TBDs at the National Cancer Institute in October 2017. Clinicians and basic scientists reviewed current data on vascular complications, hypotheses for the underlying biology and developed new collaborations to address the etiology and clinical management of vascular complications in TBDs.

[Background and objective]: The abnormal shortening of telomeres is a mechanism linking ageing to idiopathic pulmonary fibrosis (IPF) that could be useful in the clinical setting. The objective of this study was to identify the IPF patients with higher risk for telomere shortening and to investigate the outcome implications., [Methods]: Consecutive Spanish patients were included at diagnosis and followed up for 3 years. DNA blood samples from a Mexican cohort were used to validate the results found in Spanish sporadic IPF. Prior to treatment, telomere length was measured through quantitative polymerase chain reaction (qPCR) and Southern blot. Outcome was assessed according to mortality or need for lung transplantation. A multivariate regression logistic model was used for statistical analysis., [Results]: Family aggregation, age of <60 years and the presence of non‐specific immunological or haematological abnormalities were associated with a higher probability of telomere shortening. Overall, 66.6% of patients younger than 60 years with telomere shortening died or required lung transplantation, independent of functional impairment at diagnosis. By contrast, in patients older than 60 years with telomere shortening, the negative impact of telomere shortening in outcome was not significant., [Conclusion]: Our data indicate that young sporadic IPF patients (<60 years) with some non‐specific immunological or haematological abnormalities had higher risk of telomere shortening, and furthermore, they presented a poorer prognosis.

[Background]: Telomeres are nucleoprotein structures present at the terminal region of the chromosomes. Mutations in genes coding for proteins involved in telomere maintenance are causative of a number of disorders known as telomeropathies. The genetic origin of these diseases is heterogeneous and has not been determined for a significant proportion of patients., [Methods]: This article describes the genetic characterization of a cohort of patients. Telomere length was determined by Southern blot and quantitative PCR. Nucleotide variants were analyzed either by high-resolution melting analysis and Sanger sequencing of selected exons or by massive sequencing of a panel of genes., [Results]: Forty-seven patients with telomere length below the 10% of normal population, affected with three telomeropathies: dyskeratosis congenita (4), aplastic anemia (22) or pulmonary fibrosis (21) were analyzed. Eighteen of these patients presented known pathogenic or novel possibly pathogenic variants in the telomere-related genes TERT, TERC, RTEL1, CTC1 and ACD. In addition, the analyses of a panel of 188 genes related to haematological disorders indicated that a relevant proportion of the patients (up to 35%) presented rare variants in genes related to DNA repair or in genes coding for proteins involved in the resolution of complex DNA structures, that participate in telomere replication. Mutations in some of these genes are causative of several syndromes previously associated to telomere shortening., [Conclusion]: Novel variants in telomere, DNA repair and replication genes are described that might indicate the contribution of variants in these genes to the development of telomeropathies. Patients carrying variants in telomere-related genes presented worse evolution after diagnosis than the rest of patients analyzed.

In this review, we will approach the role of the regulation of telomere length and telomerase activity in different lung diseases. Telomeres are nucleo-protein structures located at the end of chromosomes that protect them from degradation. In the absence of telomerase activity, telomeres are shortened after each round of deoxyribonucleic acid (DNA) replication. When a critical size is reached, there is an induction in cell apoptosis or senescence. Telomere replication is also involved in the acquisition of the unlimited proliferative capacity that characterises tumour cells. Several diseases of lung tissue are associated either with a deficit or overactivation of telomerase activity. Idiopathic pulmonary fibrosis is associated with germinal mutations in telomerase-genes resulting in premature senescence of lung tissue accelerating the onset of the disease. Somatic mutations or polymorphisms in telomere reverse transcriptase (TERT) promoter have also been associated with upregulation of telomerase activity and lung cancer.

Mitogen-activated protein kinases (MAPK) such as p38 and the c-Jun N-terminal kinases (JNKs) are activated during the cellular response to stress signals. Their activity is regulated by the MAPK-phosphatase 1 (DUSP1), a key component of the anti-inflammatory response. Stress kinases are well-described elements of the response to otic injury and the otoprotective potential of JNK inhibitors is being tested in clinical trials. By contrast, there are no studies exploring the role of DUSP1 in hearing and hearing loss. Here we show that Dusp1 expression is age-regulated in the mouse cochlea. Dusp1 gene knock-out caused premature progressive hearing loss, as confirmed by auditory evoked responses in Dusp1-/- mice. Hearing loss correlated with cell death in hair cells, degeneration of spiral neurons and increased macrophage infiltration. Dusp1-/- mouse cochleae showed imbalanced redox status and dysregulated expression of cytokines. These data suggest that DUSP1 is essential for cochlear homeostasis in the response to stress during ageing.

Single nucleotide polymorphisms (SNPs) in DNA glycosylase genes involved in the base excision repair (BER) pathway can modify breast and ovarian cancer risk in BRCA1 and BRCA2 mutation carriers. We previously found that SNP rs34259 in the uracil-DNA glycosylase gene (UNG) might decrease ovarian cancer risk in BRCA2 mutation carriers. In the present study, we validated this finding in a larger series of familial breast and ovarian cancer patients to gain insights into how this UNG variant exerts its protective effect. We found that rs34259 is associated with significant UNG downregulation and with lower levels of DNA damage at telomeres. In addition, we found that this SNP is associated with significantly lower oxidative stress susceptibility and lower uracil accumulation at telomeres in BRCA2 mutation carriers. Our findings help to explain the association of this variant with a lower cancer risk in BRCA2 mutation carriers and highlight the importance of genetic changes in BER pathway genes as modifiers of cancer susceptibility for BRCA1 and BRCA2 mutation carriers.

The invention relates to a method to predict the response to treatment with radiotherapy combined with cisplatin-based chemotherapy in patients with cancer, preferably non-microcytic lung cancer, wherein said method is based on the detection of the presence of methylation in the IGFBP-3 gene. The present invention also relates to an in vitro method to design a customised treatment for an individual with said disease. The method of the invention may be quantitative or semi-quantitative. The present invention also relates to a probe designed for the quantitative detection of the methylation of the IGFBP-3 gene, to a kit that comprises it and to the use of the kit to predict the response of a subject to the aforementioned treatment

The invention relates to a method for predicting the response to treatment with radiotherapy combined with chemotherapy based on cisplatin in patients suffering from cancer, preferably non-small cell lung cancer, where said method is based on the detection of the presence of methylation of the gene IGFBP-3. The invention also relates to an in vitro method for designing a personalised treatment for an individual suffering from said disease. The method of the invention can be quantitative or semi-quantitative. The invention also relates to a probe for the quantitative detection of the methylation of the gene IGFBP-3, to a kit comprising same, and to the use of said kit for predicting the response of an individual receiving the described treatment

[Background]: Tenofovir is a potent inhibitor of human telomerase. The clinical relevance of this inhibition is unknown., [Methods]: A prospective cohort of human immunodeficiency virus (HIV)–infected participants with suppressed virological replication was recruited to compare whole-blood telomere length (measured by quantitative multiplex polymerase chain reaction analysis) in participants with current exposure to tenofovir disoproxil fumarate (TDF) to that in participants never exposed to TDF., [Results]: A total of 172 participants were included: 67 were in the TDF group, and 105 were in the non-TDF group (75 were receiving 2 nucleosides [of whom 69 were receiving abacavir], 25 were receiving a nucleos[t]ide reverse transcriptase inhibitor [N{t}RTI]–sparing regimen, and 5 were receiving lamivudine as the only nucleoside). After 2 years, the mean blood telomere length increased significantly in the whole cohort. The TDF group had significantly smaller gains in telomere length than the non-TDF group. In the analysis restricted to participants receiving N(t)RTIs, TDF exposure was not associated with an independent negative effect. In the non-TDF group, participants treated with 2 nucleosides also had significantly smaller gains in telomere length than those receiving N(t)RTI-sparing regimens or lamivudine as the only nucleoside., [Discussion]: In HIV-infected adults with prolonged virological suppression, treatment with TDF or abacavir was associated with smaller gains in blood telomere length after 2 years of follow-up.

Cisplatin is an election drug widely used in clinic for the treatment of advanced gastric cancer. However, the heterogeneity of the gastric tumors and its resistance to the drugs, make in some cases the response very low and the prognosis unpredictable. In this manuscript we aim to find the molecular processes involved in cisplatin-induced apoptosis in two gastric cancer cell lines with different sensitivity to the treatment: AGS and MKN45. The apoptosis induction is higher in MKN45 than in AGS cells in response to CDDP. The intrinsic apoptotic pathway study revealed that MKN45 cells undergo degradation of Mcl-1 together with an increase of Bid and Bad levels, which results in sensitivity to CDDP. In addition, DNA repair NER pathway is impair in MKN45 cells due to low levels of XPC and the absence of translocation of XPA and XPD to the nucleus after stimuli. Altogether, these results suggest that NER and Bcl-2 protein family proteins are potential targets to improve the response to cisplatin treatment.

One of the major limitations associated with platinum use is the resistance that almost invariably develops in different tumor types. In the current study, we sought to identify epigenetically regulated microRNAs as novel biomarkers of platinum resistance in lung and ovarian cancers, the ones with highest ratios of associated chemo-resistance. [Methods]: We combined transcriptomic data from microRNA and mRNA under the influence of an epigenetic reactivation treatment in a panel of four paired cisplatin -sensitive and -resistant cell lines, followed by real-time expression and epigenetic validations for accurate candidate selection in 19 human cancer cell lines. To identify specific candidate genes under miRNA regulation, we assembled “in silico” miRNAs and mRNAs sequences by using ten different algorithms followed by qRT-PCR validation. Functional assays of site-directed mutagenesis and luciferase activity, miRNAs precursor overexpression, silencing by antago-miR and cell viability were performed to confirm their specificity in gene regulation. Results were further explored in 187 primary samples obtained from ovarian tumors and controls. [Results]: We identified 4 candidates, miR-7, miR-132, miR-335 and miR-148a, which deregulation seems to be a common event in the development of resistance to cisplatin in both tumor types. miR-7 presented specific methylation in resistant cell lines, and was associated with poorer prognosis in ovarian cancer patients. Our experimental results strongly support the direct regulation of MAFG through miR-7 and their involvement in the development of CDDP resistance in human tumor cells. [Conclusion]: The basal methylation status of miR-7 before treatment may be a potential clinical epigenetic biomarker, predictor of the chemotherapy outcome to CDDP in ovarian cancer patients. To the best of our knowledge, this is the first report linking the regulation of MAFG by miRNA-7 and its role in chemotherapy response to CDDP. Furthermore, this

[Objective]: To evaluate the in vivo relevance of the inhibitory effect of tenofovir on telomerase activity observed in vitro., [Design]: Cross-sectional study of HIV-infected patients with suppressed virological replication (HIV RNA <50 copies/mL for more than 1 year)., [Methods]: Telomere length in whole blood was measured by quantitative real-time polymerase chain reaction. We performed a multivariate analysis to elucidate variables associated with telomere length and also evaluated the association between telomere length and use of tenofovir difumarate (TDF) adjusted by significant confounders., [Results]: 200 patients included, 72% men, median age 49 (IQR 45–54.5), 103 with exposure to a TDF containing antiretroviral treatment (ART) regimen (69.9% for more than 5 years) and 97 never exposed to a TDF containing ART regimen. In the multivariate analysis, significant predictors of shorter telomere length were older age (P = 0.008), parental age at birth (P = 0.038), white race (P = 0.048), and longer time of known HIV infection (10–20 and ≥20 years compared with <10 years, P = 0.003 and P = 0.056, respectively). There was no association between TDF exposure and telomere length after adjusting for possible confounding factors (age, parental age at birth, race, and time of HIV infection). Total time receiving ART and duration of treatment with nucleoside reverse transcriptase inhibitors were associated with shorter telomere length, but these associations were explained by time of known HIV infection., [Conclusions]: Our data do not suggest that telomerase activity inhibition caused by TDF in vitro leads to telomere shortening in peripheral blood of HIV-infected patients.

NHEJ1-patients develop severe progressive lymphocytopenia and premature aging of hematopoietic stem cells (HSCs) at a young age. Here we show a patient with a homozygous-NHEJ1 mutation identified by whole exome-sequencing that developed severe pancytopenia and bone marrow aplasia correlating with the presence of short telomeres. The mutation resulted in a truncated protein. In an attempt to identify the mechanism behind the short telomere phenotype found in the NHEJ1-patient we downregulated NHEJ1 expression in 293T and CD34+cells. This downregulation resulted in reduced telomerase activity and decreased expression of several telomerase/shelterin genes. Interestingly, cell lines derived from two other NHEJ1-deficient patients with different mutations also showed increased p21 expression, inhibition in expression of several telomerase complex genes and shortened telomeres. Decrease in expression of telomerase/shelterin genes did not occur when we inhibited expression of other NHEJ genes mutated in SCID patients: DNA-PK, Artemis or LigaseIV. Because premature aging of HSCs is observed only in NHEJ1 patients, we propose that is the result of senescence induced by decreased expression of telomerase/shelterin genes that lead to an inhibition of telomerase activity. Previous reports failed to find this connection because of the use of patient´s cells immortalized by TERT expression or recombined telomeres by ALT pathway. In summary, defective regulation of telomere biology together with defective V(D)J recombination can negatively impact on the evolution of the disease in these patients. Identification of telomere shortening is important since it may open new therapeutic interventions for these patients by treatments aimed to recover the expression of telomerase genes.

DNA sequencing capacity has increased tremendously in the last ten years due to the development of massive sequencing techniques, also known as Next Generation Sequencing. A large amount of information on the sequence of the human genome, its organization, transcription and regulation of gene expression has been generated form healthy individuals and also from patients suffering a broad group of diseases. The technical capacity to determine the sequence of patients’ DNAs at decreasing cost and the knowledge already generated is making possible a precise molecular diagnosis for many diseases in clinical settings. Determining the molecular basis of the disease for each particular patient has important implications in diagnosis, prognosis, genetic counselling and for the determination of an optimal treatment, moving towards a personalized medicine. In this review the available sequencing platforms will be briefly analyzed. DNA sequencing for clinical practice can be extended to different levels and the advantages and disadvantages of Whole Genome Sequencing (WGS), Whole Exome Sequencing (WES), RNA sequencing, Targeted Panel Sequencing and Mehylated DNA Sequencing will be discussed. The application of these technologies to Monogenic, Multigenic diseases and Cancer will be reviewed. Finally, the clinical implementation of massive parallel sequencing technologies and the present challenges will be discussed.

The elucidation of mechanisms involved in resistance to therapies is essential to improve the survival of patients with malignant gliomas. A major feature possessed by glioma cells that may aid their ability to survive therapy and reconstitute tumors is the capacity for self-renewal. We show here that glioma stem cells (GSCs) express low levels of MKP1, a dual-specificity phosphatase, which acts as a negative inhibitor of JNK, ERK1/2, and p38 MAPK, while induction of high levels of MKP1 expression are associated with differentiation of GSC. Notably, we find that high levels of MKP1 correlate with a subset of glioblastoma patients with better prognosis and overall increased survival. Gain of expression studies demonstrated that elevated MKP1 impairs self-renewal and induces differentiation of GSCs while reducing tumorigenesis in vivo. Moreover, we identified that MKP1 is epigenetically regulated and that it mediates the anti-tumor activity of histone deacetylase inhibitors (HDACIs) alone or in combination with temozolomide. In summary, this study identifies MKP1 as a key modulator of the interplay between GSC self-renewal and differentiation and provides evidence that the activation of MKP1, through epigenetic regulation, might be a novel therapeutic strategy to overcome therapy resistance in glioblastoma.

[ES] Determinación de la metilación y niveles de un miARN en respuesta a un compuesto antitumoral basado en platino. La presente invención se relaciona con un método para determinar la respuesta a un compuesto antitumoral basado en platino en una paciente de cáncer de ovario que comprende (i) determinar el nivel de metilación en la isla CpG de secuencia SEQ ID NO:1 y (ii) comparar el nivel de metilación en dicha isla CpG en el gen que codifica miR-7 o el nivel de expresión de miR-7 con un valor de referencia correspondiente, en donde un incremento en el nivel de metilación obtenido en (i) o una disminución en el nivel de expresión obtenido en (i) con respecto al valor de referencia correspondiente, es indicativo de que el cáncer de ovario de dicha paciente es resistente a dicho compuesto de platino. La invención también se relaciona con el uso de miR-7 o un precursor del mismo para la fabricación de un medicamento para el tratamiento de un sujeto que padece un cáncer resistente a un compuesto antitumoral basado en platino., [EN] The invention relates to a method for determining the response to an antitumour compound comprising platinum in a patient with ovarian cancer, said method comprising (i) determining the level of methylation in the CpG island of sequence SEQ ID NO:1, and (ii) comparing the level of methylation in said CpG island in the gene encoding miR-7 or the expression level of miR-7 with a corresponding reference value, in which an increase in the methylation level obtained in (i) or a decrease in the expression level obtained in (i) with respect to the corresponding reference value indicates that the patient's ovarian cancer is resistant to said platinum compound. The invention also relates to the use of miR-7 or a precursor thereof for the production of a drug for the treatment of a patient with a cancer that is resistant to a platinum-based antitumour compound.

[EN] The invention relates to a method for determining the response to an antitumour compound comprising platinum in a patient with ovarian cancer, said method comprising (i) determining the level of methylation in the CpG island of sequence SEQ ID NO:1, and (ii) comparing the level of methylation in said CpG island in the gene encoding miR-7 or the expression level of miR-7 with a corresponding reference value, in which an increase in the methylation level obtained in (i) or a decrease in the expression level obtained in (i) with respect to the corresponding reference value indicates that the patient's ovarian cancer is resistant to said platinum compound. The invention also relates to the use of miR-7 or a precursor thereof for the production of a drug for the treatment of a patient with a cancer that is resistant to a platinum-based antitumour compound., [ES] Determinación de la metilación y niveles de un miARN en respuesta a un compuesto antitumoral basado en platino. La presente invención se relaciona con un método para determinar la respuesta a un compuesto antitumoral basado en platino en una paciente de cáncer de ovario que comprende (i) determinar el nivel de metilación en la isla CpG de secuencia SEQ ID NO:1 y (ii) comparar el nivel de metilación en dicha isla CpG en el gen que codifica miR-7 o el nivel de expresión de miR-7 con un valor de referencia correspondiente, en donde un incremento en el nivel de metilación obtenido en (i) o una disminución en el nivel de expresión obtenido en (i) con respecto al valor de referencia correspondiente, es indicativo de que el cáncer de ovario de dicha paciente es resistente a dicho compuesto de platino. La invención también se relaciona con el uso de miR-7 o un precursor del mismo para la fabricación de un medicamento para el tratamiento de un sujeto que padece un cáncer resistente a un compuesto antitumoral basado en platino.

In vitro, tenofovir and abacavir induced a significant dose-dependent inhibition of telomerase activity at therapeutic concentrations in peripheral blood mononuclear cells of healthy subjects. Median inhibition of telomerase activity by tenofovir at 0.5 and 1 M was 29% [Interquartile range (IQR) 29%-34%, P = 0.042] and 28% (IQR 28%-41%, P = 0.042), respectively. Abacavir inhibition was 12% (IQR 9%-13%, P = 0.043) at 3 M and 14% (IQR 10%-29%, P = 0.043) at 10 M. Tenofovir and abacavir did not change human telomerase reverse transcriptase (hTERT) levels or mRNA levels of other telomerase complex genes. Exposure to emtricitabine or darunavir did not affect telomerase activity, hTERT protein levels, or mRNA levels of telomerase/shelterin genes.

The invention relates to a method to predict the response to treatment with radiotherapy combined with cisplatin-based chemotherapy in patients with cancer, preferably non-microcytic lung cancer, wherein said method is based on the detection of the presence of methylation in the IGFBP-3 gene. The present invention also relates to an in vitro method to design a customised treatment for an individual with said disease. The method of the invention may be quantitative or semi-quantitative. The present invention also relates to a probe designed for the quantitative detection of the methylation of the IGFBP-3 gene, to a kit that comprises it and to the use of the kit to predict the response of a subject to the aforementioned treatment