Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 64
Filter
1.
PLoS One ; 19(6): e0305073, 2024.
Article in English | MEDLINE | ID: mdl-38900837

ABSTRACT

Stable isotope methods have been used to study protein metabolism in humans; however, there application in dogs has not been frequently explored. The present study compared the methods of precursor (13C-Leucine), end-products (15N-Glycine), and amino acid oxidation (13C-Phenylalanine) to determine the whole-body protein turnover rate in senior dogs. Six dogs (12.7 ± 2.6 years age, 13.6 ± 0.6 kg bodyweight) received a dry food diet for maintenance and were subjected to all the above-mentioned methods in succession. To establish 13C and 15N kinetics, according to different methodologies blood plasma, urine, and expired air were collected using a specifically designed mask. The volume of CO2 was determined using respirometry. The study included four methods viz. 13C-Leucine, 13C-Phenylalanine evaluated with expired air, 13C-Phenylalanine evaluated with urine, and 15N-Glycine, with six dogs (repetitions) per method. Data was subjected to variance analysis and means were compared using the Tukey test (P<0.05). In addition, the agreement between the methods was evaluated using Pearson correlation and Bland-Altman statistics. Protein synthesis (3.39 ± 0.33 g.kg-0,75. d-1), breakdown (3.26 ± 0.18 g.kg-0.75.d-1), and flux estimations were similar among the four methods of study (P>0.05). However, only 13C-Leucine and 13C-Phenylalanine (expired air) presented an elevated Pearson correlation and concordance. This suggested that caution should be applied while comparing the results with the other methodologies.


Subject(s)
Leucine , Oxidation-Reduction , Phenylalanine , Animals , Dogs , Leucine/metabolism , Leucine/blood , Phenylalanine/metabolism , Phenylalanine/blood , Carbon Isotopes , Amino Acids/metabolism , Amino Acids/blood , Male , Nitrogen Isotopes , Glycine/urine , Glycine/metabolism , Glycine/blood , Proteins/metabolism , Proteins/analysis , Female
2.
Cell Biosci ; 13(1): 232, 2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38135881

ABSTRACT

BACKGROUND: mTORC2 is a critical regulator of cytoskeleton organization, cell proliferation, and cancer cell survival. Activated mTORC2 induces maximal activation of Akt by phosphorylation of Ser-473, but regulation of Akt activity and signaling crosstalk upon growth factor stimulation are still unclear. RESULTS: We identified that NUAK1 regulates growth factor-dependent activation of Akt by two mechanisms. NUAK1 interacts with mTORC2 components and regulates mTORC2-dependent activation of Akt by controlling lysosome positioning and mTOR association with this organelle. A second mechanism involves NUAK1 directly phosphorylating Akt at Ser-473. The effect of NUAK1 correlated with a growth factor-dependent activation of specific Akt substrates. NUAK1 induced the Akt-dependent phosphorylation of FOXO1/3a (Thr-24/Thr-32) but not of TSC2 (Thr-1462). According to a subcellular compartmentalization that could explain NUAK1's differential effect on the Akt substrates, we found that NUAK1 is associated with early endosomes but not with plasma membrane, late endosomes, or lysosomes. NUAK1 was required for the Akt/FOXO1/3a axis, regulating p21CIP1, p27KIP1, and FoxM1 expression and cancer cell survival upon EGFR stimulation. Pharmacological inhibition of NUAK1 potentiated the cell death effect induced by Akt or mTOR pharmacological blockage. Analysis of human tissue data revealed that NUAK1 expression positively correlates with EGFR expression and Akt Ser-473 phosphorylation in several human cancers. CONCLUSIONS: Our results showed that NUAK1 kinase controls mTOR subcellular localization and induces Akt phosphorylation, demonstrating that NUAK1 regulates the growth factor-dependent activation of Akt signaling. Therefore, targeting NUAK1, or co-targeting it with Akt or mTOR inhibitors, may be effective in cancers with hyperactivated Akt signaling.

3.
Front Cell Dev Biol ; 10: 1031262, 2022.
Article in English | MEDLINE | ID: mdl-36438565

ABSTRACT

SALL2/Sall2 is a transcription factor associated with development, neuronal differentiation, and cancer. Interestingly, SALL2/Sall2 deficiency leads to failure of the optic fissure closure and neurite outgrowth, suggesting a positive role for SALL2/Sall2 in cell migration. However, in some cancer cells, SALL2 deficiency is associated with increased cell migration. To further investigate the role of Sall2 in the cell migration process, we used immortalized Sall2 knockout (Sall2 -/- ) and Sall2 wild-type (Sall2 +/+ ) mouse embryonic fibroblasts (iMEFs). Our results indicated that Sall2 positively regulates cell migration, promoting cell detachment and focal adhesions turnover. Sall2 deficiency decreased cell motility and altered focal adhesion dynamics. Accordingly, restoring Sall2 expression in the Sall2 -/- iMEFs by using a doxycycline-inducible Tet-On system recovered cell migratory capabilities and focal adhesion dynamics. In addition, Sall2 promoted the autophosphorylation of Focal Adhesion Kinase (FAK) at Y397 and increased integrin ß1 mRNA and its protein expression at the cell surface. We demonstrated that SALL2 increases ITGB1 promoter activity and binds to conserved SALL2-binding sites at the proximal region of the ITGB1 promoter, validated by ChIP experiments. Furthermore, the overexpression of integrin ß1 or its blockade generates a cell migration phenotype similar to that of Sall2 +/+ or Sall2 -/- cells, respectively. Altogether, our data showed that Sall2 promotes cell migration by modulating focal adhesion dynamics, and this phenotype is associated with SALL2/Sall2-transcriptional regulation of integrin ß1 expression and FAK autophosphorylation. Since deregulation of cell migration promotes congenital abnormalities, tumor formation, and spread to other tissues, our findings suggest that the SALL2/Sall2-integrin ß1 axis could be relevant for those processes.

4.
Rev Med Chil ; 150(3): 331-338, 2022 Mar.
Article in Spanish | MEDLINE | ID: mdl-36156718

ABSTRACT

BACKGROUND: The incorporation of novel drugs, such as proteasome inhibitors and immunomodulators, improved considerably the survival of patients with multiple myeloma. AIM: To evaluate the effect on survival of proteasome inhibitors and immunomodulators in patients with multiple myeloma in two national hospitals. MATERIAL AND METHODS: Review of clinical records from two hospitals of Santiago. Epidemiological, clinical, laboratory and therapeutic data was obtained from 144 patients with multiple myeloma diagnosed between 2002 and 2016. RESULTS: Information was retrieved from 78 patients at one center and from 66 at the other center. The mean age at diagnosis was 58 and 62 years, the proportion of males was 53% and 52%, and presentation at stage III was 34% and 46%, respectively. The use of novel drugs, mainly bortezomib, was 90% in one of the centers and 3% in the other one. The use of autologous stem-cell transplantation was 47% and 3% respectively. The median overall survival of patients from the centers with and without access to novel drugs was 117 and 71 months respectively (p < 0.05). The five-year overall survival was 93 and 43% respectively (p < 0.05). CONCLUSIONS: The use of novel drugs, especially bortezomib, and autologous stem-cell transplantation significantly improved the survival of multiple myeloma patients treated in national hospitals. It is necessary to include them as a first line treatment.


Subject(s)
Hematopoietic Stem Cell Transplantation , Multiple Myeloma , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bortezomib/therapeutic use , Chile/epidemiology , Humans , Male , Multiple Myeloma/diagnosis , Proteasome Inhibitors/therapeutic use , Transplantation, Autologous
5.
Front Pharmacol ; 13: 912688, 2022.
Article in English | MEDLINE | ID: mdl-35814251

ABSTRACT

Rheb is a small GTPase member of the Ras superfamily and an activator of mTORC1, a protein complex master regulator of cell metabolism, growth, and proliferation. Rheb/mTORC1 pathway is hyperactivated in proliferative diseases, such as Tuberous Sclerosis Complex syndrome and cancer. Therefore, targeting Rheb-dependent signaling is a rational strategy for developing new drug therapies. Rheb activates mTORC1 in the cytosolic surface of lysosomal membranes. Rheb's farnesylation allows its anchorage on membranes, while its proper localization depends on the prenyl-binding chaperone PDEδ. Recently, the use of PDEδ inhibitors has been proposed as anticancer agents because they interrupted KRas signaling leading to antiproliferative effects in KRas-dependent pancreatic cancer cells. However, the effect of PDEδ inhibition on the Rheb/mTORC1 pathway has been poorly investigated. Here, we evaluated the impact of a new PDEδ inhibitor, called Deltasonamide 1, in Tsc2-null MEFs, a Rheb-dependent overactivated mTORC1 cell line. By using a yeast two-hybrid assay, we first validated that Deltasonamide 1 disrupts Rheb-PDEδ interaction. Accordingly, we found that Deltasonamide 1 reduces mTORC1 targets activation. In addition, our results showed that Deltasonamide 1 has antiproliferative and cytotoxic effects on Tsc2-null MEFs but has less effect on Tsc2-wild type MEFs viability. This work proposes the pharmacological PDEδ inhibition as a new approach to target the abnormal Rheb/mTORC1 activation in Tuberous Sclerosis Complex cells.

6.
Rev. méd. Chile ; 150(3): 331-338, mar. 2022. tab, graf
Article in Spanish | LILACS | ID: biblio-1409806

ABSTRACT

BACKGROUND: The incorporation of novel drugs, such as proteasome inhibitors and immunomodulators, improved considerably the survival of patients with multiple myeloma. Aim: To evaluate the effect on survival of proteasome inhibitors and immunomodulators in patients with multiple myeloma in two national hospitals. MATERIAL AND METHODS: Review of clinical records from two hospitals of Santiago. Epidemiological, clinical, laboratory and therapeutic data was obtained from 144 patients with multiple myeloma diagnosed between 2002 and 2016. Results: Information was retrieved from 78 patients at one center and from 66 at the other center. The mean age at diagnosis was 58 and 62 years, the proportion of males was 53% and 52%, and presentation at stage III was 34% and 46%, respectively. The use of novel drugs, mainly bortezomib, was 90% in one of the centers and 3% in the other one. The use of autologous stem-cell transplantation was 47% and 3% respectively. The median overall survival of patients from the centers with and without access to novel drugs was 117 and 71 months respectively (p < 0.05). The five-year overall survival was 93 and 43% respectively (p < 0.05). CONCLUSIONS: The use of novel drugs, especially bortezomib, and autologous stem-cell transplantation significantly improved the survival of multiple myeloma patients treated in national hospitals. It is necessary to include them as a first line treatment.


Subject(s)
Humans , Male , Hematopoietic Stem Cell Transplantation , Multiple Myeloma/diagnosis , Transplantation, Autologous , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chile/epidemiology , Proteasome Inhibitors/therapeutic use , Bortezomib/therapeutic use
7.
Cancers (Basel) ; 13(24)2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34944911

ABSTRACT

SALL proteins are a family of four conserved C2H2 zinc finger transcription factors that play critical roles in organogenesis during embryonic development. They regulate cell proliferation, survival, migration, and stemness; consequently, they are involved in various human genetic disorders and cancer. SALL4 is a well-recognized oncogene; however, SALL1-3 play dual roles depending on the cancer context and stage of the disease. Current reviews of SALLs have focused only on SALL2 or SALL4, lacking an integrated view of the SALL family members in cancer. Here, we update the recent advances of the SALL members in tumor development, cancer progression, and therapy, highlighting the synergistic and/or antagonistic functions they perform in similar cancer contexts. We identified common regulatory mechanisms, targets, and signaling pathways in breast, brain, liver, colon, blood, and HPV-related cancers. In addition, we discuss the potential of the SALL family members as cancer biomarkers and in the cancer cells' response to therapies. Understanding SALL proteins' function and relationship will open new cancer biology, clinical research, and therapy perspectives.

8.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1385840

ABSTRACT

RESUMEN: A pesar de que los procesos epigenéticos son estudiados ampliamente de forma general, no se habían relacionado, hasta ahora, a las alteraciones genéticas más tradicionales asociadas en la etiopatogenia del cáncer oral. La visión de carcinogénesis tradicional y la de la epigenética convergen en las mismas vías moleculares involucradas en el desarrollo del cáncer, potenciándose durante el proceso de carcinogénesis oral. A continuación se realizará una revisón de las siguientes vías moleculares VEGF-C /VEGFR; HB-EGF /EGFR; Wnt /B-catenina y las ciclinas, desde un punto de vista genético y epigenético para establecer su conexión durante el proceso de carcinogénesis oral.


ABSTRACT: Although epigenetic processes are widely studied, no one has related them to the classical genetic processes in oral cancer etiopathogenesis. The traditional carcinogenesis and epigenetic views converge in the same molecular pathways involved in cancer development, enhancing this process. This review will approach the VEGF-C/VEGFR, HB-EGF/EGFR, Wnt /B-catenin, and cyclins molecular pathways from the genetic and epigenetic views to establish their connection during the oral cancer process.

9.
Front Genet ; 12: 613808, 2021.
Article in English | MEDLINE | ID: mdl-33692826

ABSTRACT

The SALL2 transcription factor, an evolutionarily conserved gene through vertebrates, is involved in normal development and neuronal differentiation. In disease, SALL2 is associated with eye, kidney, and brain disorders, but mainly is related to cancer. Some studies support a tumor suppressor role and others an oncogenic role for SALL2, which seems to depend on the cancer type. An additional consideration is tissue-dependent expression of different SALL2 isoforms. Human and mouse SALL2 gene loci contain two promoters, each controlling the expression of a different protein isoform (E1 and E1A). Also, several improvements on the human genome assembly and gene annotation through next-generation sequencing technologies reveal correction and annotation of additional isoforms, obscuring dissection of SALL2 isoform-specific transcriptional targets and functions. We here integrated current data of normal/tumor gene expression databases along with ChIP-seq binding profiles to analyze SALL2 isoforms expression distribution and infer isoform-specific SALL2 targets. We found that the canonical SALL2 E1 isoform is one of the lowest expressed, while the E1A isoform is highly predominant across cell types. To dissect SALL2 isoform-specific targets, we analyzed publicly available ChIP-seq data from Glioblastoma tumor-propagating cells and in-house ChIP-seq datasets performed in SALL2 wild-type and E1A isoform knockout HEK293 cells. Another available ChIP-seq data in HEK293 cells (ENCODE Consortium Phase III) overexpressing a non-canonical SALL2 isoform (short_E1A) was also analyzed. Regardless of cell type, our analysis indicates that the SALL2 long E1 and E1A isoforms, but not short_E1A, are mostly contributing to transcriptional control, and reveals a highly conserved network of brain-specific transcription factors (i.e., SALL3, POU3F2, and NPAS3). Our data integration identified a conserved molecular network in which SALL2 regulates genes associated with neural function, cell differentiation, development, and cell adhesion between others. Also, we identified PODXL as a gene that is likely regulated by SALL2 across tissues. Our study encourages the validation of publicly available ChIP-seq datasets to assess a specific gene/isoform's transcriptional targets. The knowledge of SALL2 isoforms expression and function in different tissue contexts is relevant to understanding its role in disease.

10.
J Ultrasound Med ; 40(6): 1125-1130, 2021 Jun.
Article in English | MEDLINE | ID: mdl-32896906

ABSTRACT

OBJECTIVES: Infantile hemangiomas (IHs) are the most common benign tumors in children. Color Doppler ultrasound is a noninvasive imaging modality that can show subclinical anatomic parameters in a wide range of dermatologic conditions. The purpose of this study was to describe the ultrasound characteristics of IHs and look for subclinical features with the potential to influence the involution and therapeutic response. METHODS: A review of the ultrasound database of children with clinical and ultrasound IH diagnoses was conducted. The clinically reported duration and the ultrasound assessment of the proliferative phase were compared. Descriptive and statistical analyses of qualitative and quantitative parameters of the series were performed. Significance was set at P < .05. RESULTS: A total of 204 IHs were included. Twenty percent had arteriovenous shunts; 15% had afferent branches from main regional arteries; and almost 30% showed involvement of deep structures. Sixty-one percent of IHs were in the head and neck. Deep hemangiomas showed significantly thicker lesional vessels. A prolonged proliferative stage was significantly associated with a higher presence of arteriovenous shunts and a higher peak systolic velocity of the arterial vessels (≥15 cm/s) within the lesions. CONCLUSIONS: Color Doppler ultrasound can support the detection of subclinical anatomic features that may potentially influence the involution and response to treatment of IHs. Some of these characteristics may serve as potential markers to predict and manage IHs in prolonged proliferative stages.


Subject(s)
Hemangioma , Skin Neoplasms , Child , Hemangioma/diagnostic imaging , Humans , Infant , Neck , Skin Neoplasms/diagnostic imaging , Ultrasonography , Ultrasonography, Doppler, Color
12.
Front Oncol ; 10: 1123, 2020.
Article in English | MEDLINE | ID: mdl-32754444

ABSTRACT

NUAK1 is an AMPK-related kinase located in the cytosol and the nucleus, whose expression associates with tumor malignancy and poor patient prognosis in several cancers. Accordingly, NUAK1 was associated with metastasis because it promotes cell migration and invasion in different cancer cells. Besides, NUAK1 supports cancer cell survival under metabolic stress and maintains ATP levels in hepatocarcinoma cells, suggesting a role in energy metabolism in cancer. However, the underlying mechanism for this metabolic function, as well as its link to NUAK1 subcellular localization, is unclear. We demonstrated that cytosolic NUAK1 increases ATP levels, which associates with increased mitochondrial respiration, supporting that cytosolic NUAK1 is involved in mitochondrial function regulation in cancer cells. NUAK1 inhibition led to the formation of "donut-like" structures, providing evidence of NUAK1-dependent mitochondrial morphology regulation. Additionally, our results indicated that cytosolic NUAK1 increases the glycolytic capacity of cancer cells under mitochondrial inhibition. Nuclear NUAK1 seems to be involved in the metabolic switch to glycolysis. Altogether, our results suggest that cytosolic NUAK1 participates in mitochondrial ATP production and the maintenance of proper glycolysis in cancer cells. Our current studies support the role of NUAK1 in bioenergetics, mitochondrial homeostasis, glycolysis and metabolic capacities. They suggest different metabolic outcomes depending on its subcellular localization. The identified roles of NUAK1 in cancer metabolism provide a potential mechanism relevant for tumor progression and its association with poor patient prognosis in several cancers. Further studies could shed light on the molecular mechanisms involved in the identified metabolic NUAK1 functions.

13.
G3 (Bethesda) ; 10(3): 1113-1124, 2020 03 05.
Article in English | MEDLINE | ID: mdl-31974097

ABSTRACT

Plant breeders regularly evaluate multiple traits across multiple environments, which opens an avenue for using multiple traits in genomic prediction models. We assessed the potential of multi-trait (MT) genomic prediction model through evaluating several strategies of incorporating multiple traits (eight agronomic and malting quality traits) into the prediction models with two cross-validation schemes (CV1, predicting new lines with genotypic information only and CV2, predicting partially phenotyped lines using both genotypic and phenotypic information from correlated traits) in barley. The predictive ability was similar for single (ST-CV1) and multi-trait (MT-CV1) models to predict new lines. However, the predictive ability for agronomic traits was considerably increased when partially phenotyped lines (MT-CV2) were used. The predictive ability for grain yield using the MT-CV2 model with other agronomic traits resulted in 57% and 61% higher predictive ability than ST-CV1 and MT-CV1 models, respectively. Therefore, complex traits such as grain yield are better predicted when correlated traits are used. Similarly, a considerable increase in the predictive ability of malting quality traits was observed when correlated traits were used. The predictive ability for grain protein content using the MT-CV2 model with both agronomic and malting traits resulted in a 76% higher predictive ability than ST-CV1 and MT-CV1 models. Additionally, the higher predictive ability for new environments was obtained for all traits using the MT-CV2 model compared to the MT-CV1 model. This study showed the potential of improving the genomic prediction of complex traits by incorporating the information from multiple traits (cost-friendly and easy to measure traits) collected throughout breeding programs which could assist in speeding up breeding cycles.


Subject(s)
Genome, Plant , Hordeum/genetics , Models, Genetic , Multifactorial Inheritance , DNA, Plant/genetics , Genomics , Genotype , Phenotype , Plant Breeding , Polymorphism, Single Nucleotide
14.
J Ultrasound Med ; 39(5): 845-857, 2020 May.
Article in English | MEDLINE | ID: mdl-31705709

ABSTRACT

OBJECTIVES: To test the capability of 70-MHz ultrasound for detecting initial ultrasound signs of hidradenitis suppurativa (HS) linked to severity. METHODS: A cross-sectional study of the ultrasound images of patients with HS was conducted and compared with a healthy control group. Detection and identification of early subclinical ultrasound signs in the lesional and perilesional areas of the HS cases in comparison with the control group were performed. Statistical analyses included mean, dispersion measures, the Kruskal-Wallis test, and bivariate and multivariate ordered logistic regression studies. Significance was assessed at P < .05. RESULTS: A total of 139 patients with HS met the criteria and showed abnormalities of the hair follicles such as a curved shape, ballooning, and protrusion into pseudocysts, collections, or tunnels (donor of keratin sign). Significant increases in the sizes of the hair follicles and hair shafts were found in HS cases. The following ultrasound signs were significantly linked to severity: a connecting band between the base of adjacent hair follicles (bridge sign), a fragment of the hair shaft extruding through a dilated hair follicle (sword sign), and retained cylindrical fragments of keratin in the dermis. Two patterns of fragmentation of the keratin were detected: multifragment and cylindrical. CONCLUSIONS: Ultrasound can detect early HS signs that are significantly linked to severity and 2 types of fragmentation of the keratin, which could support the generation and perpetuation of the fluid collections and tunnels. These ultrasound signs can help prompt diagnosis and management, the development and testing of medications, and the measure of treatment outcomes in HS.


Subject(s)
Hidradenitis Suppurativa/diagnostic imaging , Keratins/metabolism , Ultrasonography/methods , Adolescent , Adult , Child , Cross-Sectional Studies , Female , Hair Follicle/diagnostic imaging , Hair Follicle/metabolism , Hair Follicle/physiopathology , Hidradenitis Suppurativa/metabolism , Hidradenitis Suppurativa/physiopathology , Humans , Male , Middle Aged , Retrospective Studies , Severity of Illness Index , Young Adult
15.
Neurobiol Dis ; 130: 104497, 2019 10.
Article in English | MEDLINE | ID: mdl-31176720

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by motor neuron death. A 20% of familial ALS cases are associated with mutations in the gene coding for superoxide dismutase 1 (SOD1). The accumulation of abnormal aggregates of different proteins is a common feature in motor neurons of patients and transgenic ALS mice models, which are thought to contribute to disease pathogenesis. Developmental morphogens, such as the Wnt family, regulate numerous features of neuronal physiology in the adult brain and have been implicated in neurodegeneration. ß-catenin is a central mediator of both, Wnt signaling activity and cell-cell interactions. We previously reported that the expression of mutant SOD1 in the NSC34 motor neuron cell line decreases basal Wnt pathway activity, which correlates with cytosolic ß-catenin accumulation and impaired neuronal differentiation. In this work, we aimed a deeper characterization of ß-catenin distribution in models of ALS motor neurons. We observed extensive accumulation of ß-catenin supramolecular structures in motor neuron somas of pre-symptomatic mutant SOD1 mice. In cell-cell appositional zones of NSC34 cells expressing mutant SOD1, ß-catenin displays a reduced co-distribution with E-cadherin accompanied by an increased association with the gap junction protein Connexin-43; these findings correlate with impaired intercellular adhesion and exacerbated cell coupling. Remarkably, pharmacological inhibition of the glycogen synthase kinase-3ß (GSK3ß) in both NSC34 cell lines reverted both, ß-catenin aggregation and the adverse effects of mutant SOD1 expression on neuronal differentiation. Our findings suggest that early defects in ß-catenin distribution could be an underlying factor affecting the onset of neurodegeneration in familial ALS.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , Motor Neurons/metabolism , beta Catenin/metabolism , Animals , Cell Differentiation/physiology , Cells, Cultured , Disease Models, Animal , Humans , Mice
16.
J Cell Biochem ; 120(9): 16088-16107, 2019 09.
Article in English | MEDLINE | ID: mdl-31090959

ABSTRACT

NUAK1 is a serine/threonine kinase member of the AMPK-α family. NUAK1 regulates several processes in tumorigenesis; however, its regulation and molecular targets are still poorly understood. Bioinformatics analysis predicted that the majority of NUAK1 localizes in the nucleus. However, there are no studies about the regulation of NUAK1 subcellular distribution. Here, we analyzed NUAK1 localization in several human cell lines, mouse embryo fibroblasts, and normal mouse tissues. We found that NUAK1 is located in the nucleus and also in the cytoplasm. Through bioinformatics analysis and studies comparing subcellular localization of wild type and NUAK1 mutants, we identified a conserved bipartite nuclear localization signal at the N-terminal domain of NUAK1. Based on mass spectrometry analysis, we found that NUAK1 interacts with importin-ß members including importin-ß1 (KPNB1), importin-7 (IPO7), and importin-9 (IPO9). We confirmed that importin-ß members are responsible for NUAK1 nuclear import through the inhibition of importin-ß by Importazole and the knockdown of either IPO7 or IPO9. In addition, we found that oxidative stress induces NUAK1 cytoplasmic accumulation, indicating that oxidative stress affects NUAK1 nuclear transport. Thus, our study is the first evidence of an active nuclear transport mechanism regulating NUAK1 subcellular localization. These data will lead to investigations of the molecular targets of NUAK1 according to its subcellular distribution, which could be new biomarkers or targets for cancer therapies.


Subject(s)
Nuclear Localization Signals/metabolism , Protein Kinases/metabolism , Repressor Proteins/metabolism , beta Karyopherins/metabolism , Active Transport, Cell Nucleus , Animals , Cell Line , Cytoplasm/metabolism , HCT116 Cells , HEK293 Cells , HeLa Cells , Humans , MCF-7 Cells , Mice , Oxidative Stress , Protein Kinases/genetics , Repressor Proteins/genetics
17.
Biochim Biophys Acta Gene Regul Mech ; 1862(6): 657-669, 2019 06.
Article in English | MEDLINE | ID: mdl-31075539

ABSTRACT

Variation in Disrupted-in-Schizophrenia 1 (DISC1) increases the risk for neurodegenerative diseases, schizophrenia, and other mental disorders. However, the functions of DISC1 associated with the development of these diseases remain unclear. DISC1 has been reported to inhibit Akt/mTORC1 signaling, a major regulator of translation, and recent studies indicate that DISC1 could exert a direct role in translational regulation. Here, we present evidence of a novel role of DISC1 in the maintenance of protein synthesis during oxidative stress. In order to investigate DISC1 function independently of Akt/mTORC1, we used Tsc2-/- cells, where mTORC1 activation is independent of Akt. DISC1 knockdown enhanced inhibition of protein synthesis in cells treated with sodium arsenite (SA), an oxidative agent used for studying stress granules (SGs) dynamics and translational control. N-acetyl-cysteine inhibited the effect of DISC1, suggesting that DISC1 affects translation in response to oxidative stress. DISC1 decreased SGs number in SA-treated cells, but resided outside SGs and maintained protein synthesis independently of a proper SG nucleation. DISC1-dependent stimulation of translation in SA-treated cells was supported by its interaction with eIF3h, a component of the canonical translation initiation machinery. Consistent with a role in the homeostatic maintenance of translation, DISC1 knockdown or overexpression decreased cell viability after SA exposure. Our data suggest that DISC1 is a relevant component of the cellular response to stress, maintaining certain levels of translation and preserving cell integrity. This novel function of DISC1 might be involved in its association with pathologies affecting tissues frequently exposed to oxidative stress.


Subject(s)
Arsenites/pharmacology , Nerve Tissue Proteins/metabolism , Oxidative Stress/drug effects , Sodium Compounds/pharmacology , Animals , Cell Survival/drug effects , Cytoplasmic Granules/metabolism , DNA Helicases/metabolism , Eukaryotic Initiation Factor-3/metabolism , Gene Expression Regulation , Gene Knockdown Techniques , HEK293 Cells , Humans , Mechanistic Target of Rapamycin Complex 1 , Mice , Nerve Tissue Proteins/genetics , Oncogene Protein v-akt , Poly-ADP-Ribose Binding Proteins/metabolism , RNA Helicases/metabolism , RNA Recognition Motif Proteins/metabolism , Transcriptome , Tuberous Sclerosis Complex 2 Protein/genetics
18.
Cell Death Dis ; 10(2): 73, 2019 01 25.
Article in English | MEDLINE | ID: mdl-30683840

ABSTRACT

Protein kinase CK2 is a highly conserved and constitutively active Ser/Thr-kinase that phosphorylates a large number of substrates, resulting in increased cell proliferation and survival. A known target of CK2 is Akt, a player in the PI3K/Akt/mTORC1 signaling pathway, which is aberrantly activated in 32% of colorectal cancer (CRC) patients. On the other hand, mTORC1 plays an important role in the regulation of protein synthesis, cell growth, and autophagy. Some studies suggest that CK2 regulates mTORC1 in several cancers. The most recently developed CK2 inhibitor, silmitasertib (formerly CX-4945), has been tested in phase I/II trials for cholangiocarcinoma and multiple myeloma. This drug has been shown to induce autophagy and enhance apoptosis in pancreatic cancer cells and to promote apoptosis in non-small cell lung cancer cells. Nevertheless, it has not been tested in studies for CRC patients. We show in this work that inhibition of CK2 with silmitasertib decreases in vitro tumorigenesis of CRC cells in response to G2/M arrest, which correlates with mTORC1 inhibition and formation of large cytoplasmic vacuoles. Notably, molecular markers indicate that these vacuoles derive from massive macropinocytosis. Altogether, these findings suggest that an aberrantly elevated expression/activity of CK2 may play a key role in CRC, promoting cell viability and proliferation in untreated cells, however, its inhibition with silmitasertib promotes methuosis-like cell death associated to massive catastrophic vacuolization, accounting for decreased tumorigenicity at later times. These characteristics of silmitasertib support a potential therapeutic use in CRC patients and probably other CK2-dependent cancers.


Subject(s)
Cell Death/drug effects , Colorectal Neoplasms/metabolism , Naphthyridines/pharmacology , Protein Kinase Inhibitors/pharmacology , Vacuoles/pathology , Carcinogenesis/drug effects , Casein Kinase II/antagonists & inhibitors , Cell Cycle Checkpoints/drug effects , Cell Movement/drug effects , Cell Survival/drug effects , Colorectal Neoplasms/pathology , HCT116 Cells , HT29 Cells , Humans , Phenazines , Pinocytosis/drug effects , Transfection
19.
J Ultrasound Med ; 38(8): 1995-2004, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30570163

ABSTRACT

OBJECTIVES: To explore the capability of very high-frequency ultrasound (US; 50-71 MHz) to detect the normal morphologic characteristics of the hair follicles and tracts, sebaceous glands, Montgomery glands, apocrine glands, and arrector pili muscles. METHODS: A retrospective study, approved by the Institutional Review Board, evaluated the normal US morphologic characteristics of the hair and adnexal structures in a database of very high-frequency US images extracted from the perilesional or contralateral healthy skin of 1117 consecutive patients who underwent US examinations for localized lesions of the skin and 10 healthy individuals from December 2017 to June 2018. These images were matched with their counterparts from the database of normal histologic images according to the corporal region. The Cohen concordance test and regional mean diameters of the hair follicles and adnexal structures were analyzed. RESULTS: The normal hair follicles and tracts, sebaceous glands, Montgomery glands, apocrine glands, and arrector pili muscles were observed on US images and matched their histological counterparts in all the corporal regions. There was significant US concordance (κ = 0.82; P = .0001) among observers. Regional mean diameters (millimeters) of the hair follicles, sebaceous glands, and apocrine glands are provided. CONCLUSIONS: The hair follicles and tracts, sebaceous glands, Montgomery glands, apocrine glands, and arrector pili muscles are detectable with very high-frequency US, including some regional and anatomic variants. Knowledge of their normal US appearances is a requisite for detecting subclinical changes, understanding the physiopathologic characteristics, and supporting the early diagnosis and management of common dermatologic diseases.


Subject(s)
Apocrine Glands/anatomy & histology , Hair Follicle/anatomy & histology , Mammary Glands, Human/anatomy & histology , Muscle, Smooth/anatomy & histology , Sebaceous Glands/anatomy & histology , Ultrasonography/methods , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Retrospective Studies , Young Adult
20.
Article in English | MEDLINE | ID: mdl-29778644

ABSTRACT

SALL2 is a transcription factor involved in development and disease. Deregulation of SALL2 has been associated with cancer, suggesting that it plays a role in the disease. However, how SALL2 is regulated and why is deregulated in cancer remain poorly understood. We previously showed that the p53 tumor suppressor represses SALL2 under acute genotoxic stress. Here, we investigated the effect of Histone Deacetylase Inhibitor (HDACi) Trichostatin A (TSA), and involvement of Sp1 on expression and function of SALL2 in Jurkat T cells. We show that SALL2 mRNA and protein levels were enhanced under TSA treatment. Both, TSA and ectopic expression of Sp1 transactivated the SALL2 P2 promoter. This transactivation effect was blocked by the Sp1-binding inhibitor mithramycin A. Sp1 bound in vitro and in vivo to the proximal region of the P2 promoter. TSA induced Sp1 binding to the P2 promoter, which correlated with dynamic changes on H4 acetylation and concomitant recruitment of p300 or HDAC1 in a mutually exclusive manner. Our results suggest that TSA-induced Sp1-Lys703 acetylation contributes to the transcriptional activation of the P2 promoter. Finally, using a CRISPR/Cas9 SALL2-KO Jurkat-T cell model and gain of function experiments, we demonstrated that SALL2 upregulation is required for TSA-mediated cell death. Thus, our study identified Sp1 as a novel transcriptional regulator of SALL2, and proposes a novel epigenetic mechanism for SALL2 regulation in Jurkat-T cells. Altogether, our data support SALL2 function as a tumor suppressor, and SALL2 involvement in cell death response to HDACi.

SELECTION OF CITATIONS
SEARCH DETAIL
...