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Oncogene addiction postulates that the survival and growth of certain tumor cells is dependent upon the activity of one oncogene, despite their multiple genetic and epigenetic abnormalities. This phenomenon provides a foundation for molecular targeted therapy and a rationale for oncogene-based stratification. We have previously reported that the Promyelocytic Leukemia protein (PML) is upregulated in triple negative breast cancer (TNBC) and it regulates cancer-initiating cell function, thus suggesting that this protein can be therapeutically targeted in combination with PML-based stratification. However, the effects of PML perturbation on the bulk of tumor cells remained poorly understood. Here we demonstrate that TNBC cells are addicted to the expression of this nuclear protein. PML inhibition led to a remarkable growth arrest combined with features of senescence in vitro and in vivo. Mechanistically, the growth arrest and senescence were associated to a decrease in MYC and PIM1 kinase levels, with the subsequent accumulation of CDKN1B (p27), a trigger of senescence. In line with this notion, we found that PML is associated to the promoter regions of MYC and PIM1, consistent with their direct correlation in breast cancer specimens. Altogether, our results provide a feasible explanation for the functional similarities of MYC, PIM1, and PML in TNBC and encourage further study of PML targeting strategies for the treatment of this breast cancer subtype. Aologies to those whose related publications were not cited due to space limitations. LA, AS, MPu, AA-A, and LV-J were supported by the Basque Government of education. IH was supported by the Program "Juan de la Cierva" from MINECO. FC acknowledges the Proteomics Unit at VHIO is a member ProteoRed, PRB3 (Grant IPT17/0019-ISCIII-SGEFI/ERDF. RB acknowledges projects BFU2017-84653-P, Consolider BFU2014-57703-REDC, and SAF2017-90900-REDT (MINECO/FEDER, EU). The work of VT is founded by Fundacion Vasca de Innovacion e Investigacion Sanitarias, BIOEF (BIO15/CA/052), the AECC J.P. Bizkaia, the Basque Department of Health (2016111109) and the MINECO (RTI2018-097267-B-I00 (MCIU/AEI/FEDER, UE)). AA was supported by ERC consolidator (683136) and Swiss Cancer League (KFS4267-08-2017) grant, Dr. Josef Steiner Foundation, Swiss CardOnco-Grant of Alfred and Annemarie von Sick grant, Helmut Horten Foundation, SNSF (310030_176045) and PCUK (RIA15-ST2-018). NM-M was supported by the Spanish Association Against Cancer (AECC), AECC JP Vizcaya and CIBERONC. The work of A. Carracedo is supported by the Basque Department of Industry, Tourism and Trade (Elkartek) and the department of education (IKERTALDE IT1106-16), the BBVA foundation, the MINECO (SAF2016-79381R (FEDER/EU); Severo Ochoa Excellence Accreditation SEV2016-0644; Excellence Networks SAF2016-81975-REDT), European Training Networks Project (H2020-MSCA-ITN-308 2016 721532), the AECC (IDEAS175CARR, GCTRA18006CARR), La Caixa Foundation (HR17-00094), FERO foundation, the AstraZeneca Oncology prize and the European Research Council (Starting Grant 336343, PoC 754627). CIBERONC was co-funded with FEDER funds and funded by ISCIII.

Colon cancer is one of the most frequently occurring types of cancers in the world. Primary tumours are treated very efficiently, but the metastatic cases are known to have severe outcomes. Therefore, the aim of the present study was to obtain a greater understanding of the transformation of primary colon cancer cells into metastatic phenotypes. Small changes in protein expression provoke the metastatic phenotype transformation. More sensitive methods to detect small variations are required. A murine colon cancer cell line with metastatic characteristics in a very early phase was created in order to investigate the first steps of transformation using a murine liver metastasis model. The protein expression patterns of metastatic and non-metastatic cells were compared using the stable isotope labelling by amino acids in cell culture method in combination with mass spectrometry. Quantitative proteomics data indicated that nicotinamide adenine dinucleotide hydride (NADH) dehydrogenase complex I was overexpressed in metastatic cells with respect to non-metastatic cells. Since the NADH dehydrogenase complex catalyses the oxidation of NADH to NAD+, the functionality of the complex was studied by measuring the amount of NADH. The results revealed that metastatic cells accumulate more NADH and reactive oxygen species. In addition, the mitochondrial membrane potential of metastatic cells was lower than that of non-metastatic cells, indicating that the activity of NADH dehydrogenase and the mitochondrial oxidative chain were decreased in metastatic cells. During the incipient transformation of primary cancer cells, NADH dehydrogenase complex I was overexpressed but then became inactive due to the Warburg effect, which inhibits mitochondrial activity. In the first step of transformation, the high energy demand required in an adverse environment is fulfilled by overexpressing components of the respiratory chain, a fact that should be considered for future anti-metastatic therapies.

SummaryDespite public awareness of its deleterious effects, smoking remains a major cause of death. Indeed, it is a risk factor for atherothrombotic complications and in line with this, the introduction of smoking ban in public areas reduced smoking-associated cardiovascular complications. Nonetheless, smoking remains a major concern, and molecular mechanisms by which it causes cardiovascular disease are not known. Peripheral blood monocytes from healthy smokers displayed increased JNK2 and tissue factor (TF) gene expression compared to non-smokers (n=15, p

The peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) is a prostate tumor suppressor that controls the balance between anabolism and catabolism. PGC1A downregulation in prostate cancer is causally associated with the development of metastasis. Here we show that the transcriptional complex formed by PGC1α and Estrogen related receptor 1 alpha (ERRα) controls the aggressive properties of prostate cancer cells. PGC1α expression significantly decreased migration and invasion of various prostate cancer cell lines. This phenotype was consistent with remarkable cytoskeletal remodeling and inhibition of integrin alpha 1 and beta 4 expression both in vitro and in vivo. CRISPR/Cas9-based deletion of ERRα suppressed PGC1α regulation of cytoskeletal organization and invasiveness. Mechanistically, PGC1α expression decreased MYC levels and activity prior to inhibition of invasiveness. In addition, PGC1α and ERRα associated at the MYC promoter, supporting the inhibitory activity PGC1α. The inverse correlation between PGC1α-ERRα activity and MYC levels was corroborated in multiple prostate cancer datasets. Altogether, these results support that PGC1α-ERRα functions as a tumor suppressive transcriptional complex through the regulation of metabolic and signaling events.

The PPARγ coactivator 1 alpha (PGC1α) is a prostate tumor suppressor that controls the balance between anabolism and catabolism. PGC1A downregulation in prostate cancer is causally associated with the development of metastasis. Here we show that the transcriptional complex formed by PGC1α and estrogen-related receptor 1 alpha (ERRα) controls the aggressive properties of prostate cancer cells. PGC1α expression significantly decreased migration and invasion of various prostate cancer cell lines. This phenotype was consistent with remarkable cytoskeletal remodeling and inhibition of integrin alpha 1 and beta 4 expression, both in vitro and in vivo. CRISPR/Cas9-based deletion of ERRα suppressed PGC1α regulation of cytoskeletal organization and invasiveness. Mechanistically, PGC1α expression decreased MYC levels and activity prior to inhibition of invasiveness. In addition, PGC1α and ERRα associated at the MYC promoter, supporting the inhibitory activity PGC1α. The inverse correlation between PGC1α–ERRα activity and MYC levels was corroborated in multiple prostate cancer datasets. Altogether, these results support that PGC1α–ERRα functions as a tumor-suppressive transcriptional complex through the regulation of metabolic and signaling events. Significance: These findings describe how downregulation of the prostate tumor suppressor PGC1 drives invasiveness and migration of prostate cancer cells.

The dysregulation of gene expression is an enabling hallmark of cancer. Computational analysis of transcriptomics data from human cancer specimens, complemented with exhaustive clinical annotation, provides an opportunity to identify core regulators of the tumorigenic process. Here we exploit well-annotated clinical datasets of prostate cancer for the discovery of transcriptional regulators relevant to prostate cancer. Following this rationale, we identify Microphthalmia-associated transcription factor (MITF) as a prostate tumor suppressor among a subset of transcription factors. Importantly, we further interrogate transcriptomics and clinical data to refine MITF perturbation-based empirical assays and unveil Crystallin Alpha B (CRYAB) as an unprecedented direct target of the transcription factor that is, at least in part, responsible for its tumor-suppressive activity in prostate cancer. This evidence was supported by the enhanced prognostic potential of a signature based on the concomitant alteration of MITF and CRYAB in prostate cancer patients. In sum, our study provides proof-of-concept evidence of the potential of the bioinformatics screen of publicly available cancer patient databases as discovery platforms, and demonstrates that the MITF-CRYAB axis controls prostate cancer biology.

Background Anaplastic lymphoma kinase (ALK) is a key oncogenic driver in lung adenocarcinoma patients and its fusion proteins are routinely assessed. The microfluidic tissue processor (MTP) device is based on a chip-confined low-volume technology allowing for rapid immunohistochemistry/immunofluorescence (IHC/IF) stainings of formalin-fixed paraffin-embedded (FFPE) or frozen tissue samples. Methods A novel ALK IF protocol was developed for the MTP device using the primary mouse anti-human ALK antibody clone 5A4. FFPE tumor whole sections from 14 resected lung adenocarcinoma patients documented to be ALK positive (ALK+) by automated chromogenic IHC and/or FISH were used. MTP-derived IF immunoreactivity was measured by computerized analysis of digitalized images on individual frames of tumor epithelia and surrounding stroma, using an ImageJ plug-in. Results The 5A4 antibody yielded saturated immunoreactivity at an incubation time of 4 min on a titration curve ranging from 2 to 32 min. Total staining time on the MTP device was 18 min including secondary IgG Alexa Fluor 647. MTP-based ALK IF confirmed all 12 cases; with epithelial signal above stromal staining based on computerized pixel-based measurement. MTP-IF (mean intensity levels 458 to 1301) and chromogenic IHC (H-score 120 to 300) showed an equal range of variation of 2.8 and 2.5 folds, respectively, and a trend for direct correlation (p-value 0.051). Conclusion The newly developed protocol for immunofluorescent detection of ALK protein with the MTP device confirms chromogenic IHC results on FFPE lung adenocarcinoma specimens. MTP-based IF is fast and reliable. We foresee this study to be a first step opening the road for further realization of microfluidic-based assays for rapid simultaneous detection of targetable oncogenic and immune-system related markers in their topographical context to investigate tumour heterogeneity and micro-environmental interactions. Electronic supplementary material The online version of this article (10.1186/s13000-018-0757-1) contains supplementary material, which is available to authorized users.

The dysregulation of gene expression is an enabling hallmark of cancer. Computational analysis of transcriptomics data from human cancer specimens, complemented with exhaustive clinical annotation, provides an opportunity to identify core regulators of the tumorigenic process. Here we exploit well-annotated clinical datasets of prostate cancer for the discovery of transcriptional regulators relevant to prostate cancer. Following this rationale, we identify Microphthalmia-associated transcription factor (MITF) as a prostate tumor suppressor among a subset of transcription factors. Importantly, we further interrogate transcriptomics and clinical data to refine MITF perturbation-based empirical assays and unveil Crystallin Alpha B (CRYAB) as an unprecedented direct target of the transcription factor that is, at least in part, responsible for its tumor-suppressive activity in prostate cancer. This evidence was supported by the enhanced prognostic potential of a signature based on the concomitant alteration of MITF and CRYAB in prostate cancer patients. In sum, our study provides proof-of-concept evidence of the potential of the bioinformatics screen of publicly available cancer patient databases as discovery platforms, and demonstrates that the MITF-CRYAB axis controls prostate cancer biology. The work of V. Torrano is funded by Fundacion Vasca de Innovacion e Investigacion Sanitarias, BIOEF (BIO15/CA/052), the AECC J.P. Bizkaia and the Basque Department of Health (2016111109). The work of A. Carracedo is supported by the Basque Department of Industry, Tourism and Trade (Etortek) and the Department of Education (IKERTALDE IT1106-16, also participated by A. Gomez-Munoz), the BBVA Foundation, the MINECO (SAF2016-79381-R (FEDER/EU); Severo Ochoa Excellence Accreditation SEV-2016-0644; Excellence Networks SAF2016-81975-REDT), European Training Networks Project (H2020-MSCA-ITN-308 2016 721532), the AECC IDEAS16 (IDEAS175CARR) and the European Research Council (Starting Grant 336343, PoC 754627). CIBERONC was co-funded with FEDER funds. The work of M. Graupera is supported by the MINECO (SAF2014-59950-P). The work of A. Aransay is supported by the Basque Department of Industry, Tourism and Trade (Etortek and Elkartek Programs), the Innovation Technology Department of Bizkaia County, CIBERehd Network and Spanish MINECO the Severo Ochoa Excellence Accreditation (SEV-2016-0644). R. Barrio acknowledges Spanish MINECO (BFU2014-52282-P, Consolider BFU2014-57703-REDC), the Departments of Education and Industry of the Basque Government (PI2012/42) and the Bizkaia County. J. Starkova acknowledges the Ministry of Health of Czech Republic AZV NV15-28848A. We are thankful to the Basque Biobank for Research (BIOEF) for the custody and management of human prostate specimens used in this study.

Los mecanismos epigenéticos, entre los que está implicada la modificación covalente de histonas, son esenciales para el mantenimiento estable de la actividad génica en las células. Estos mecanismos también están implicados en la aparición de enfermedades como el cáncer colorrectal (CCR), siendo la metástasis hepática una de las formas más agresivas de la misma al producir una drástica disminución de la esperanza de vida del enfermo. Las modificaciones en las histonas, conocidas recientemente como código histónico, afectan a la estructura de la cromatina y juegan un papel importante en el desarrollo de la tumorogénesis. Sin embargo, se sabe poco acerca de aquellas células que adquieren la capacidad de metastatizar, y es por ello que en el presente trabajo se estudian las diferencias epigenéticas entre células tumorales primarias y células tumorales metastásicas para el patrón de trimetilación de la histona H3 en tres residuos diferentes del aminoácido lisina: lisina 4 (H3K4me3), lisina 9 (H3K9me3) y lisina 27 (H3K27me3). Epigenetic mechanisms, among histone covalent modifications are included, they are essential for the cell’s stable gene activity maintenance. These mechanisms are also involved in the onset of diseases such as colorectal cancer (CRC), being hepatic metastasis one of the most agressive forms of the disease due to the drastic decrease of life expectancy of the patient. Modifications in histones, recently called as “histone code’’, affect the chromatin structure and play an important role in the developement of tumorigenesis. Little is known about those cells that acquire metastatic capacity. This is the reason why in this work, epigenetic differences on the patterns of trimethylation of histone H3 (for 3 different amino acids: lysine 4 (H3K4me3), lysine 9 (H3K9me3) and lysine 27 (H3K27me3)) are studied between primary tumoral cells and metastatic tumoral cells.

Figure S1. Evaluation of different blocking solution for ALK IF. Figure S2. Evaluation of two different detection systems for ALK IF. Figure S3. Sharp confinement of ALK immunoreactivity inside the MTP chamber. Figure S4. Immunofluorescence for pan-cytokeratin using the MTP device. Figure S5. Comparison between IF and IHC. (PDF 929 kb)

Figure S1. Evaluation of different blocking solution for ALK IF. Figure S2. Evaluation of two different detection systems for ALK IF. Figure S3. Sharp confinement of ALK immunoreactivity inside the MTP chamber. Figure S4. Immunofluorescence for pan-cytokeratin using the MTP device. Figure S5. Comparison between IF and IHC. (PDF 929 kb)

Table S1. Summary of clinico-pathological patient data. (DOCX 79 kb)

Table S1. Summary of clinico-pathological patient data. (DOCX 79 kb)

Oncogene addiction postulates that the survival and growth of certain tumor cells is dependent upon the activity of one oncogene, despite their multiple genetic and epigenetic abnormalities. This phenomenon provides a foundation for molecular targeted therapy and a rationale for oncogene-based stratification. We have previously reported that the Promyelocytic Leukemia protein (PML) is upregulated in triple negative breast cancer (TNBC) and it regulates cancer-initiating cell function, thus suggesting that this protein can be therapeutically targeted in combination with PML-based stratification. However, the effects of PML perturbation on the bulk of tumor cells remained poorly understood. Here we demonstrate that TNBC cells are addicted to the expression of this nuclear protein. PML inhibition led to a remarkable growth arrest combined with features of senescence in vitro and in vivo. Mechanistically, the growth arrest and senescence were associated to a decrease in MYC and PIM1 kinase levels, with the subsequent accumulation of CDKN1B (p27), a trigger of senescence. In line with this notion, we found that PML is associated to the promoter regions of MYC and PIM1, consistent with their direct correlation in breast cancer specimens. Altogether, our results provide a feasible explanation for the functional similarities of MYC, PIM1, and PML in TNBC and encourage further study of PML targeting strategies for the treatment of this breast cancer subtype., Cell Death and Differentiation, 27 (4), ISSN:1350-9047, ISSN:1476-5403