Vitamina D y Cáncer

SEBBM Divulgación: Acercate a nuestros científicos.[ES]: La vitamina D, o más exactamente su metabolito la 1α,25-dihidroxivitamina D3 (1α,25(OH)2D3, calcitriol), es uno de los principales reguladores de la expresión génica. Modula la transcripción de centenares de genes y la actividad de enzimas y vías de señalización. Sus efectos sobre la proliferación y diferenciación celulares han disparado el interés en la 1α,25(OH)2D3.[EN]: Vitamin D, particularly its metabolite 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3, calcitriol), is a main regulator of gene expression. 1α,25(OH)2D3 modulates the transcription rate of hundreds of genes and the activity of several enzymes and signalling pathways. A series of novel effects recently described make of 1α,25(OH)2D3 an attractive subject of study.Peer Reviewe

c-Jun N-terminal kinase phosphorylation is a biomarker of plitidepsin activity

This is an open access article distributed under the Creative Commons Attribution License.-- et al.Plitidepsin is an antitumor drug of marine origin currently in Phase III clinical trials in multiple myeloma. In cultured cells, plitidepsin induces cell cycle arrest or an acute apoptotic process in which sustained activation of c-Jun N-terminal kinase (JNK) plays a crucial role. With a view to optimizing clinical use of plitidepsin, we have therefore evaluated the possibility of using JNK activation as an in vivo biomarker of response. In this study, we show that administration of a single plitidepsin dose to mice xenografted with human cancer cells does indeed lead to increased phosphorylation of JNK in tumors at 4 to 12 h. By contrast, no changes were found in other in vitro plitidepsin targets such as the levels of phosphorylated-ERK, -p38MAPK or the protein p27KIP1. Interestingly, plitidepsin also increased JNK phosphorylation in spleens from xenografted mice showing similar kinetics to those seen in tumors, thereby suggesting that normal tissues might be useful for predicting drug activity. Furthermore, plitidepsin administration to rats at plasma concentrations comparable to those achievable in patients also increased JNK phosphorylation in peripheral mononuclear blood cells. These findings suggest that changes in JNK activity provide a reliable biomarker for plitidepsin activity and this could be useful for designing clinical trials and maximizing the efficacy of plitidepsin.This work has been partially supported by grants (Programa Cenit, CEN-20091016, SAF2010-18302 and Fondo Europeo de Desarrollo Regional-Instituto de Salud Carlos III, RD12/0036/0021) from Ministerio de Economía y Competitividad of Spain.Peer Reviewe

Mechanisms of resistance to vitamin D action in human cancer cells

El pdf es la versión post-print.Initial clinical trials in cancer patients with vitamin D compounds have shown acceptable toxicity but low activity. A number of mechanisms responsible for resistance to their action in cancer cells have been recently reported. They include reduced intracellular availability of 1α,25-dihydroxyvitamin D3 [1,25(OH)2D], loss of vitamin D receptor (VDR) expression and deregulation of transcription corepressors that modulate VDR action. Here, we summarize the data in the literature on the altered activity of the enzymes (CYP27B1, CYP24A1) that controls 1,25(OH)2D levels, the repression of VDR by the transcription factor Snail1 and the overexpression of several VDR corepressors (NCoR, SMRT) in cancer cells. A better understanding of these processes must contribute to improved protocols for the clinical use of vitamin D compounds.The work in authors’ laboratory is supported by the Ministerio de Ciencia e Innovación of Spain, Comunidad de Madrid and European Union.Peer Reviewe

Vitamina D y cáncer

Vitamin D, particularly its metabolite 1a, 25-dihydroxyvi- tamin D3 (1a,25(OH)2D3, calcitriol), is a main regulator of gene expression. 1a,25(OH)2D3 modulates the transcription rate of hundreds of genes and the activity of several enzymes and signalling pathways. A series of novel effects recently described make of 1a,25(OH)2D3 an attractive subject of study.La vitamina D, o más exactamente su metabolito la 1a,25-dihi- droxivitamina D3 (1a, 25(OH)2D3, calcitriol), es uno de los principales re- guladores de la expresión génica. Modula la transcripción de centenares de genes y la actividad de enzimas y vías de señalización. Sus efectos sobre la proliferación y diferenciación celulares han disparado el interés en la 1a,25(OH)2D3

The transcription factors Snail1 and Snail2 repress vitamin D receptor during colon cancer progression

El pdf es el manuscrito de autor.Vitamin D receptor (VDR) mediates the antitumoral action of the active vitamin D metabolite 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3). However, VDR expression is lost during colon cancer progression, possibly causing unresponsiveness to 1,25(OH)2D3. Although several mechanisms responsible for resistance to 1,25(OH)2D3 action in different types of cancer had been reported, none explained the loss of VDR expression. We have found that the transcription factors Snail1 and Snail2, known as inducers of epithelial-to-mesenchymal transition (EMT), inhibit VDR expression and block 1,25(OH)2D3 action in colon cancer cells. Snail1 and Snail2 have an additive repressing effect on VDR gene promoter. These effects are specific to the Snail family, as other transcription factors that function as EMT inducers do not inhibit VDR expression in colon cancer cells. Moreover, we also found that the RNA expression of SNAI1 and SNAI2 is upregulated in human colorectal tumors and inversely correlates with that of VDR. Our results suggest that high levels of SNAIL1 and SNAIL2 are a probable cause of VDR downregulation and 1,25(OH)2D3 unresponsiveness in colon cancer. In addition, they may contribute to the improvement of protocols for the clinical use of vitamin D compounds, as they indicate that advanced colon cancer patients overexpressing SNAIL1 and SNAIL2 are not suitable candidates for this therapy. © 2010 Elsevier Ltd.The work in authors’ laboratories is supported by the Ministerio de Ciencia e Innovación of Spain (SAF2007-60341, ISCIII-RETIC RD06/0020/0009 and RD06/0020/0020), Comunidad de Madrid (S-GEN-0266/2006) and European Union (MRTN-CT-2005-019496, NucSys).Peer Reviewe

The complex life of DICKKOPF-1 in cancer cells

This work is licensed under a Creative Commons Attribution 4.0 International License.The role of DICKKOPF (DKK)-1 in human cancer is controversial. DKK-1 behaves as an inhibitor of the canonical Wnt/β-catenin signaling pathway acting at the plasma membrane, although several studies have proposed effects that are independent of the inhibition of β-catenin transcriptional activity, in some cases mediated by the activation of c-Jun N-terminal kinase (JNK). Recently, a proportion of DKK-1 protein has been found within the nucleus of human intestinal epithelial cells following an apical-to-basal crypt decreasing gradient, and in that of colon carcinoma cells. Moreover, we show here that in the human mammary gland DKK-1 is also present within the nucleus of many differentiated luminal epithelial cells and in that of a small proportion of myoepithelial cells. Nuclear DKK-1 binds to actively transcribed chromatin and regulates the expression of specific genes, some of which are involved in cell proliferation, survival and stemness, and in the defense against xenobiotics. This may explain the finding that while DKK-1 is downregulated more rapidly in the nucleus than in the cytosol during colon carcinoma progression, its expression remains high in a percentage of patients who do not respond to chemotherapy. Available data suggest that the accumulation of DKK-1 in the nucleus of colon carcinoma cells depends on signals from the surrounding tumor microenvironment.Work in authors' laboratories is supported by grants from Ministerio de Economía y Competitividad of Spain-Fondo Europeo de Desarrollo Regional (FEDER) (SAF2013-43468-R), Comunidad de Madrid (S2010/BMD-2344 Colomics2), and FEDER-Instituto de Salud Carlos III (RD12/0036/0021; RD12/0036/0051, PT13/0010/0012 and PI12/01552).Peer reviewe

Ectopic expression of the erythrocyte band 3 anion exchange protein, using a new avian retrovirus vector

12 pages, 5 figures, 3 tables.A retrovirus vector was constructed from the genome of avian erythroblastosis virus ES4. The v-erbA sequences of avian erythroblastosis virus were replaced by those coding for neomycin phosphotransferase, creating a gag-neo fusion protein which provides G418 resistance as a selectable marker. The v-erbB sequences following the splice acceptor were replaced by a cloning linker allowing insertion of foreign genes. The vector has been tested in conjunction with several helper viruses for the transmission of G418 resistance, titer, stability, transcription, and the transduction and expression of foreign genes in both chicken embryo fibroblasts and the QT6 quail cell line. The results show that the vector is capable of producing high titers of Neor virus from stably integrated proviruses. These proviruses express a balanced ratio of genome length to spliced transcripts which are efficiently translated into protein. Using the Escherichia coli beta-galactosidase gene cloned into the vector as a test construct, expression of enzyme activity could be detected in 90 to 95% of transfected target cells and in 80 to 85% of subsequently infected cells. In addition, a cDNA encoding the avian erythrocyte band 3 anion exchange protein has been expressed from the vector in both chicken embryo fibroblasts and QT6 cells and appears to function as an active, plasma membrane-based anion transporter. The ectopic expression of band 3 protein provides a visual marker for vector function in these cells.The support of the European Molecular Biology Laboratory during the initial phases of this work is acknowledged. S.F. was supported by the Swedish Medical Research Foundation, and A.M. was supported by the Juan March Foundation. Grants were obtained from the Swedish Cancer Society, the Wallenberg Foundation, the Children's Cancer Fund, and Kjell and Marta Beijer's Foundation.Peer reviewe

Epigenetic repression of ROR2 has a Wnt-mediated, pro-tumourigenic role in colon cancer

9 páginas, 4 figuras.-- et al.[Background]: Wnt factors control cell differentiation through semi-independent molecular cascades known as the β-catenin-dependent (canonical) and -independent (non-canonical) Wnt signalling pathways. Genetic and epigenetic alteration of components of the canonical Wnt signalling pathway is one of the primary mechanisms underlying colon cancer. Despite increasing evidence of the role of the non-canonical pathways in tumourigenesis, however, the underlying molecular mechanisms are poorly understood. [Results]: Here we report that the receptor tyrosine kinase-like orphan receptor 2 (ROR2), a transmembrane receptor for Wnt factors that activates non-canonical pathways, is frequently repressed by aberrant promoter hypermethylation in human colon cancer cell lines and primary tumours. By restoring ROR2 activity in colon cancer cells harbouring ROR2 promoter hypermethylation, we show that the role of ROR2 in colon cancer cells is mediated, at least in part, by canonical Wnt and that its epigenetic-dependent loss can be pro-tumourigenic. [Conclusions]: Our data show the importance of epigenetic alterations of ROR2 in colon cancer, highlighting the close interconnection between canonical and non-canonical Wnt signalling pathways in this type of tumour.AM is funded by the Spanish Ministerio de Ciencia e Innovación (MICINN; SAF2007-60341, ISCIII-RETIC RD06/0020/0009), VC receives a fellowship from the Spanish FPU Research Programme, EL and CH are recipients of fellowships from the Spanish FIS Research Programme. The Instituto Universitario de Oncología is supported by Obra Social Cajastur, Spain. This work was supported by the MICINN (PI061267; PS09/02454; Ref. 200820I172).Peer reviewe

NADPH oxidase 1 as a new regulator of the WNT pathway and the protective effect of vitamin D in colorectal cancer

Trabajo presentado en el 43rd Annual Meeting of the SEBBM, celebrado en Barcelona (España) del 19 al 22 de julio de 2021.Worldwide, colorectal cancer (CRC) is the third most common malignant neoplasm and the second leading cause of cancer-associated mortality, with an estimated increase in global prevalence of 60% by 2030 (1,2). Mutational inactivation of adenomatous polyposis coli (APC) is the hallmark of CRC and leads to an overactivation of WNT signaling that favors the development and progression of CRC (3). Large epidemiological studies suggest that the diabetic population is at increased risk for site-specific cancers, including CRC (4). Our laboratory has shown that hyperglycemia induces the accumulation of ROS in CRC but not healthy cells, driving the activation of a newly described ROS/AMPK/EP300 axis that enhances Wnt/b-catenin signaling. Increased EP300 leads to increased acetylation of β-catenin at K354, a requirement for nuclear accumulation and transcriptional activation of WNT target genes (5,6). The critical role driven by ROS suggest a possible involvement of the NADPH oxidases (NOX family, as a source of ROS. Specifically, NOX 1 and NOX 4 are expressed in colon epithelial cells, and their overexpression in CRC cells promotes cell proliferation and invasiveness (7,8,9,10). Our results indicate that hyperglycemia significantly increases NOX1 levels, in correlation with increased ROS production in CRC cells, suggesting a possible regulation of the ROS/ AMPK/EP300 axis by NOX1. Antioxidant mechanisms dealing with NOX1-induced ROS should be effective against CRC. Vitamin D (1α, 25-dihydroxyvitamin D3) is a powerful antioxidant that inhibits proliferation and promotes differentiation of CRC cells at least partially through inhibition of Wnt/β-catenin signalling. Consequently, vitamin D deficiency is associated with poor survival to CRC (11,12). Our results indicate that vitamin D causes a reduction in the levels and / or activity of some members of the NOX family by turning off the ROS/AMPK/EP300/β-catenin axis and its proliferative and tumorigenic effects. The data suggest a new antitumor mechanism of vitamin D linked to its anti-oxidant action. Our results integrate independent epidemiological links between vitamin D deficiency, diabetes and cancer in one overarching and unifying mechanism

p38γ and p38δ as biomarkers in the interplay of colon cancer and inflammatory bowel diseases

descripción no proporcionada por scopusThis research was funded by the MCIN/AEI/10.13039/501100011033 (PID2019-108349RB100 and SAF2016-79792R) to AC and JJSE; Villum Foundation, grant no. 13152 to KA; by Agencia Estatal de Investigación (PID2019-104867RBI00/AEI/10.13039/501100011033) and the Instituto de Salud Carlos III- Fondo Europeo de Desarrollo Regional (CIBERONC/CB16/12/00273 and ICI20/00057) to AM and AB. PF received MCIN FPI fellowship (BES-2017-080139)