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1.
Int J Mol Sci ; 24(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894765

RESUMO

The Schlafen 11 (SLFN11) protein has recently emerged as pivotal in DNA damage conditions, with predictive potential for tumor response to cytotoxic chemotherapies. Recent discoveries also showed that the programmed death ligand 1 (PD-L1) protein can be found on malignant cells, providing an immune evasion mechanism exploited by different tumors. Additionally, excessive generation of free radicals, redox imbalance, and consequential DNA damage can affect intestinal cell homeostasis and lead to neoplastic transformation. Therefore, our study aimed to investigate the significance of SLFN11 and PD-L1 proteins and redox status parameters as prognostic biomarkers in CRC patients. This study included a total of 155 CRC patients. SLFN11 and PD-L1 serum levels were measured with ELISA and evaluated based on redox status parameters, sociodemographic and clinical characteristics, and survival. The following redox status parameters were investigated: spectrophotometrically measured superoxide dismutase (SOD), sulfhydryl (SH) groups, advanced oxidation protein products (AOPP), malondialdehyde (MDA), pro-oxidant-antioxidant balance (PAB), and superoxide anion (O2•-). The prooxidative score, antioxidative score, and OXY-SCORE were also calculated. The results showed significantly shorter survival in patients with higher OXY-SCOREs and higher levels of serum SLFN11, while only histopathology-analysis-related factors showed significant prognostic value. OXY-SCORE and SLFN11 levels may harbor prognostic potential in CRC patients.


Assuntos
Antígeno B7-H1 , Neoplasias Colorretais , Humanos , Antígeno B7-H1/metabolismo , Prognóstico , Oxirredução , Antioxidantes/metabolismo , Neoplasias Colorretais/patologia , Proteínas Nucleares/genética
2.
Gene ; 859: 147217, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36690223

RESUMO

BACKGROUND: Considering the impact of SMAD7 deregulation in colorectal cancer (CRC) progression and the significance of single nucleotide variant (SNV)-mediated disruptions of microRNA (miRNA)-dependent regulation for cancer susceptibility, our study aimed to analyze genetic variation in the SMAD7 3' untranslated region ( 3'UTR) in CRC, measure differences in allelic mRNA expression, and evaluate its interference with miRNA-mediated post-transcriptional regulation. PATIENTS AND METHODS: This study included 80 patients with different CRC stages and six human colon cancer cell lines of various histological origins. SMAD7 3'UTR was analyzed by direct sequencing, followed by the relative quantification of differential allelic expression of detected variants by allele-specific qRT-PCR. In silico tools were employed for predictions of regulatory consequences of detected variants. RESULTS: A total of four different SNVs in one cell line and nine patients were found, among which were a novel somatic point variant and three already known germline variants (rs16950113, rs1050799536, and rs1043778717). All evaluated SNVs exhibited variable extents of allelic imbalance in expression. In silico analysis predicted significant effects of SNVs on miRNA binding efficiency, with each SNV disrupting existing and creating new target sites for one or more miRNAs. CONCLUSION: Imbalance observed in the expression of SNV alleles altering miRNA binding suggests that all investigated SNVs are potential contributing factors impacting SMAD7 expression regulation in CRC that further studies should investigate.


Assuntos
Neoplasias Colorretais , MicroRNAs , Proteína Smad7 , Humanos , Regiões 3' não Traduzidas , Alelos , Desequilíbrio Alélico , Neoplasias Colorretais/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Polimorfismo de Nucleotídeo Único , Proteína Smad7/genética , Proteína Smad7/metabolismo
3.
Proteomics Clin Appl ; 17(1): e2100116, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35997210

RESUMO

PURPOSE: In the search for candidate predictive biomarkers to evaluate response to neoadjuvant chemoradiotherapy (nCRT) in rectal cancer, only a few studies report proteomic profiles of tumor tissue before and after nCRT. The aim of our study was to determine differentially expressed proteins between responders and non-responders before and after the therapy in order to identify candidate molecules for prediction and follow-up of response to nCRT. EXPERIMENTAL DESIGN: The study has included tissue sections of rectal tumor and non-tumor mucosa from five responders and five non-responders taken before and after nCRT from patients with locally advanced rectal cancer. Extracted proteins were analyzed by LC-MS/MS analysis followed by a set of bioinformatics analyses. RESULT: Proteomics analysis provided a mean of approximately 1050 protein identifications per sample. A comparison of proteomic profiles between responders and non-responders has identified 18 differentially expressed proteins. Pathway analysis demonstrated high metabolic activity in non-responders' tumors before nCRT, indicating the presence of intrinsic chemoradioresistance in these subjects. Two proteins associated with poor prognosis in colorectal cancer, ADAM10 and CAD, were identified as candidate predictive biomarkers as they were present in non-responders only. CONCLUSIONS AND CLINICAL RELEVANCE: Shortlisted proteins from our study should be further validated as candidate biomarkers for response to routinely applied nCRT protocols.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Proteômica/métodos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Neoplasias Retais/terapia , Neoplasias Retais/metabolismo , Neoplasias Retais/patologia , Biomarcadores , Resultado do Tratamento
4.
Colorectal Dis ; 24(9): 1054-1062, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35426481

RESUMO

AIM: The aim of this study was to investigate whether the application of nanofat containing stem cells improves continence in women who had previously undergone anal sphincteroplasty with unsatisfactory long-term outcomes. METHOD: This prospective pilot study included nine women with various degrees of anal incontinence who had previously undergone anal sphincteroplasty due to obstetric trauma. In all patients, the Wexner Incontinence Score (WS) and Faecal Incontinence Quality of Life Score (FIQLS), as well as anal manometry and endoanal ultrasound measurements, were performed before the procedure and during follow-up. In all patients, liposuction was performed and 50 ml of raw lipoaspirate was obtained and processed using a NanoFat Kit device. Approximately 20 ml of the mechanically emulsified and filtrated fat was obtained and the anal sphincter complex was infiltrated with it. Patient follow-up was conducted in person or via telephone 6 and 12 months after the procedure. RESULTS: The squeeze pressure was significantly increased 6 months after the procedure (p = 0.01). The external anal sphincter measured at the 12 o'clock position was significantly thicker (p = 0.04). A significant decrease in the WS was observed both 6 and 12 months after the procedure compared with baseline values (p < 0.05 for both). CONCLUSION: This study is the first to show that the application of nanofat as an injectable product improves continence in patients with unsatisfactory results after sphincteroplasty, suggesting it to be a promising and effective therapeutic tool. The procedure is safe and can be easily performed as an ambulatory procedure.


Assuntos
Incontinência Fecal , Canal Anal/lesões , Canal Anal/cirurgia , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Feminino , Humanos , Projetos Piloto , Gravidez , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento
5.
BMC Cancer ; 22(1): 72, 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35034624

RESUMO

BACKGROUND: Transcripts with alternative 5'-untranslated regions (UTRs) result from the activity of alternative promoters and they can determine gene expression by influencing its stability and translational efficiency, thus executing complex regulation of developmental, physiological and pathological processes. Transcriptional regulation of human SMAD4, a key tumor suppressor deregulated in most gastrointestinal cancers, entails four alternative promoters. These promoters and alternative transcripts they generate remain unexplored as contributors to the SMAD4 deregulation in cancer. The aim of this study was to investigate the relative abundance of the transcript SMAD4-201 in colorectal cell lines and tissues in order to establish if its fluctuations may be associated with colorectal cancer (CRC). METHODS: Relative abundance of SMAD4-201 in total SMAD4 mRNA was analyzed using quantitative PCR in a set of permanent human colon cell lines and tumor and corresponding healthy tissue samples from patients with CRC. RESULTS: The relative abundance of SMAD4-201 in analyzed cell lines varied between 16 and 47%. A similar relative abundance of SMAD4-201 transcript was found in the majority of analyzed human tumor tissue samples, and it was averagely 20% lower in non-malignant in comparison to malignant tissue samples (p = 0.001). Transcript SMAD4-202 was not detectable in any of the analyzed samples, so the observed fluctuations in the composition of SMAD4 transcripts can be attributed to transcripts other than SMAD4-201 and SMAD4-202. CONCLUSION: The expression profile of SMAD4-201 in human tumor and non-tumor tissue samples may indicate the translational potential of this molecule in CRC, but further research is needed to clarify its usability as a potential biomarker for early diagnosis.


Assuntos
Neoplasias Colorretais/genética , Proteína Smad4/genética , Animais , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Colo/metabolismo , Humanos , Camundongos , Reação em Cadeia da Polimerase
6.
Exp Mol Pathol ; 123: 104714, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34717960

RESUMO

Inhibitory SMAD7 and common mediator SMAD4 play crucial roles in SMAD-dependent TGF-ß signaling that is often disrupted in colorectal cancer (CRC). This study aimed to profile the expression of SMAD7 and SMAD4 in primary and metastatic CRC and to evaluate their significance in disease progression and therapy response. The expression of SMAD7 and SMAD4 genes was analyzed by quantitative real-time PCR in tissues from 35 primary and metastatic CRC patients and in vitro in 7 human cell lines originating from colon tissue. Expression levels of SMAD7 and SMAD4, as well as their ratio, were determined and their association with tumor characteristics and response to therapy were evaluated. SMAD4 level was significantly lower in tumors compared to non-tumor tissues in both primary (p = 0.001) and metastatic (p = 0.001) CRC patients, while tumor expression of SMAD7 was significantly lower from non-tumor tissue only in metastatic patients (p = 0.017). SMAD7/SMAD4 ratio was elevated in CRC primary tumor tissues and cell lines compared to corresponding non-tumor tissues and cell line, respectively (p = 0.003). SMAD7 expression was significantly elevated in primary tumor tissues obtained from responders to neoadjuvant chemoradiotherapy (nCRT) compared to non-responders (p = 0.014). Alterations of expression and ratio of SMAD7 and SMAD4 in CRC cell lines, primary rectal cancer, and liver metastasis emphasize the importance of these genes in different stages of disease progression. Differential expression of SMAD7 in responders versus non-responders to nCRT should be further investigated for its potential predictive value.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/radioterapia , Proteína Smad4/genética , Proteína Smad7/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Fator de Crescimento Transformador beta/genética
7.
AAPS J ; 19(4): 1002-1016, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28540623

RESUMO

Quantitative systems pharmacology (QSP) modeling has become increasingly important in pharmaceutical research and development, and is a powerful tool to gain mechanistic insights into the complex dynamics of biological systems in response to drug treatment. However, even once a suitable mathematical framework to describe the pathophysiology and mechanisms of interest is established, final model calibration and the exploration of variability can be challenging and time consuming. QSP models are often formulated as multi-scale, multi-compartment nonlinear systems of ordinary differential equations. Commonly accepted modeling strategies, workflows, and tools have promise to greatly improve the efficiency of QSP methods and improve productivity. In this paper, we present the QSP Toolbox, a set of functions, structure array conventions, and class definitions that computationally implement critical elements of QSP workflows including data integration, model calibration, and variability exploration. We present the application of the toolbox to an ordinary differential equations-based model for antibody drug conjugates. As opposed to a single stepwise reference model calibration, the toolbox also facilitates simultaneous parameter optimization and variation across multiple in vitro, in vivo, and clinical assays to more comprehensively generate alternate mechanistic hypotheses that are in quantitative agreement with available data. The toolbox also includes scripts for developing and applying virtual populations to mechanistic exploration of biomarkers and efficacy. We anticipate that the QSP Toolbox will be a useful resource that will facilitate implementation, evaluation, and sharing of new methodologies in a common framework that will greatly benefit the community.


Assuntos
Modelos Teóricos , Fluxo de Trabalho , Calibragem , Simulação por Computador , Imunoconjugados/química
8.
Front Pharmacol ; 5: 232, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25374542

RESUMO

Multiple software programs are available for designing and running large scale system-level pharmacology models used in the drug development process. Depending on the problem, scientists may be forced to use several modeling tools that could increase model development time, IT costs and so on. Therefore, it is desirable to have a single platform that allows setting up and running large-scale simulations for the models that have been developed with different modeling tools. We developed a workflow and a software platform in which a model file is compiled into a self-contained executable that is no longer dependent on the software that was used to create the model. At the same time the full model specifics is preserved by presenting all model parameters as input parameters for the executable. This platform was implemented as a model agnostic, therapeutic area agnostic and web-based application with a database back-end that can be used to configure, manage and execute large-scale simulations for multiple models by multiple users. The user interface is designed to be easily configurable to reflect the specifics of the model and the user's particular needs and the back-end database has been implemented to store and manage all aspects of the systems, such as Models, Virtual Patients, User Interface Settings, and Results. The platform can be adapted and deployed on an existing cluster or cloud computing environment. Its use was demonstrated with a metabolic disease systems pharmacology model that simulates the effects of two antidiabetic drugs, metformin and fasiglifam, in type 2 diabetes mellitus patients.

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