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1.
Onco Targets Ther ; 17: 63-78, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38313386

RESUMO

Introduction: Peritoneal metastases from colorectal cancer (CRC) present a significant clinical challenge with poor prognosis, often unresponsive to systemic chemotherapy. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment approach for select patients. The use of curcumin, a natural compound with antitumor properties, in HIPEC is of interest due to its lower side effects compared to conventional drugs and potential for increased efficacy through direct delivery to the peritoneal cavity. Methods: An in vitro hyperthermic model was developed to simulate clinical HIPEC conditions. Three colon cancer cell lines (SK-CO-1, COLO205, SNU-C1) representing different genetic mutations (p53, KRAS, BRAF) were treated with either curcumin (25 µM) or mitomycin-C (1 µM) for 1, 2, or 3 hours. Post-treatment, cells were incubated at 37°C (normothermia) or 42°C (hyperthermia). Cell viability and proliferation were assessed at 24, 48 and 72 hours post-treatment using Annexin V/PI, MTT assay, trypan blue exclusion, and Hoffman microscopy. Results: Hyperthermia significantly enhanced the antitumor efficacy of curcumin, evidenced by a two-fold reduction in cell viability compared to normothermia across all cell lines. In the SNU-C1 cell line, which harbors a p53 mutation, mitomycin-C failed to significantly impact cell viability, unlike curcumin, suggesting mutation-specific differences in treatment response. Discussion: The findings indicate that hyperthermia augments the antitumor effects of curcumin in vitro, supporting the hypothesis that curcumin could be a more effective HIPEC agent than traditional drugs like mitomycin-C. Mutation-associated differences in response to treatments were observed, particularly in p53 mutant cells. While further studies are needed, these preliminary results suggest that curcumin in HIPEC could represent a novel therapeutic strategy for CRC patients with peritoneal metastases. This approach may offer improved outcomes with fewer side effects, particularly in genetically distinct CRC subtypes.

2.
Vaccines (Basel) ; 11(12)2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38140268

RESUMO

Mucosal vaccines protect against respiratory virus infection by stimulating the production of IgA antibodies that protect against virus invasion of the mucosal epithelium. In this study, a novel protein subunit mucosal vaccine was constructed for protection against infection by the beta coronavirus SARS-CoV-2. The vaccine was assembled by linking a gene encoding the SARS-CoV-2 virus S1 angiotensin converting enzyme receptor binding domain (ACE-2-RBD) downstream from a DNA fragment encoding the cholera toxin B subunit (CTB), a mucosal adjuvant known to stimulate vaccine immunogenicity. A 42 kDa vaccine fusion protein was identified in homogenates of transformed E. coli BL-21 cells by acrylamide gel electrophoresis and by immunoblotting against anti-CTB and anti-ACE-2-RBD primary antibodies. The chimeric CTB-SARS-CoV-2-ACE-2-RBD vaccine fusion protein was partially purified from clarified bacterial homogenates by nickel affinity column chromatography. Further vaccine purification was accomplished by polyacrylamide gel electrophoresis and electro-elution of the 42 kDa chimeric vaccine protein. Vaccine protection against SARS-CoV-2 infection was assessed by oral, nasal, and parenteral immunization of BALB/c mice with the CTB-SARS-CoV-2-ACE-2-RBD protein. Vaccine-induced SARS-CoV-2 specific antibodies were quantified in immunized mouse serum by ELISA analysis. Serum from immunized mice contained IgG and IgA antibodies that neutralized SARS-CoV-2 infection in Vero E6 cell cultures. In contrast to unimmunized mice, cytological examination of cell necrosis in lung tissues excised from immunized mice revealed no detectable cellular abnormalities. Mouse behavior following vaccine immunization remained normal throughout the duration of the experiments. Together, our data show that a CTB-adjuvant-stimulated CTB-SARS-CoV-2-ACE-2-RBD chimeric mucosal vaccine protein synthesized in bacteria can produce durable and persistent IgA antibodies in mice that neutralize the SARS-CoV-2 subvariant Omicron BA.1.1.

3.
Cancers (Basel) ; 15(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37894437

RESUMO

Pancreatic cancer (PCa) remains a formidable global health challenge, with high mortality rates and limited treatment options. While advancements in pharmacology have led to improved outcomes for various cancers, PCa continues to exhibit significant health disparities, disproportionately affecting certain populations. This paper explores the intersection of pharmacology and anthropology in understanding the health disparities associated with PCa. By considering the socio-cultural, economic, and behavioral factors that influence the development, diagnosis, treatment, and outcomes of PCa, pharmacologic anthropology provides a comprehensive framework to address these disparities and improve patient care.

4.
Ann Surg Oncol ; 30(6): 3833-3844, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36864326

RESUMO

BACKGROUND: Liquid biopsies have become an integral part of cancer management as minimally invasive options to detect molecular and genetic changes. However, current options show poor sensitivity in peritoneal carcinomatosis (PC). Novel exosome-based liquid biopsies may provide critical information on these challenging tumors. In this initial feasibility analysis, we identified an exosome gene signature of 445 genes (ExoSig445) from colon cancer patients, including those with PC, that is distinct from healthy controls. METHODS: Plasma exosomes from 42 patients with metastatic and non-metastatic colon cancer and 10 healthy controls were isolated and verified. RNAseq analysis of exosomal RNA was performed and differentially expressed genes (DEGs) were identified by the DESeq2 algorithm. The ability of RNA transcripts to discriminate control and cancer cases was assessed by principal component analysis (PCA) and Bayesian compound covariate predictor classification. An exosomal gene signature was compared with tumor expression profiles of The Cancer Genome Atlas. RESULTS: Unsupervised PCA using exosomal genes with greatest expression variance showed stark separation between controls and patient samples. Using separate training and test sets, gene classifiers were constructed capable of discriminating control and patient samples with 100% accuracy. Using a stringent statistical threshold, 445 DEGs fully delineated control from cancer samples. Furthermore, 58 of these exosomal DEGs were found to be overexpressed in colon tumors. CONCLUSIONS: Plasma exosomal RNAs can robustly discriminate colon cancer patients, including patients with PC, from healthy controls. ExoSig445 can potentially be developed as a highly sensitive liquid biopsy test in colon cancer.


Assuntos
Neoplasias do Colo , Exossomos , Humanos , Biomarcadores Tumorais/metabolismo , Exossomos/genética , Exossomos/metabolismo , Teorema de Bayes , Neoplasias do Colo/patologia , RNA/metabolismo
6.
Proteomics Clin Appl ; 17(2): e2100085, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36217952

RESUMO

PURPOSE: Peritoneal carcinomatosis (PC), metastasized from colorectal cancer (CRC), remains a highly lethal disease. Outcomes of PC is significantly influenced by the amount of intra-abdominal tumor burden and therefore diagnostic tests that facilitate earlier diagnosis could improve PC treatment and patient outcomes. EXPERIMENTAL DESIGN: Using mass-spectrometry-based proteomics, we characterized the protein features of circulating exosomes in the context of CRC PC, CRC with liver metastasis, and primary CRC limited to the colon. We profiled exosomes isolated from patient plasma to identify exosome-associated protein cargoes released by these cancer types. RESULTS: Analysis of the resulting data identified metastasis-specific exosome protein signatures. Bioinformatic analyses confirmed enrichment of proteins annotated to vesicle-associated processes and intracellular compartments, as well as representation of cancer hallmark functions and processes. CONCLUSION AND CLINICAL RELEVANCE: This research yielded distinct protein profiles for the CRC patient groups and suggests the utility of plasma exosome proteomic analysis for a better understanding of PC development and metastasis.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Exossomos , Neoplasias Peritoneais , Humanos , Projetos Piloto , Neoplasias Peritoneais/patologia , Proteômica , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Biomarcadores/metabolismo , Exossomos/metabolismo , Neoplasias Colorretais/metabolismo
7.
Onco Targets Ther ; 15: 1147-1160, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238134

RESUMO

Background: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease with poor prognosis, as it is difficult to predict or circumvent, and it develops chemoresistance quickly. One cellular mechanism associated with chemoresistance is alternative splicing dysfunction, a process through which nascent mRNA is spliced into different isoforms. Survivin (Baculoviral IAP Repeat-Containing Protein 5 (BIRC5)), a member of the inhibitor of apoptosis (IAP) protein family and a cell cycle-associated oncoprotein, is overexpressed in most cancers and undergoes alternative splicing (AS) to generate six different splicing isoforms. Methods: To determine if survivin splice variants (SSV) could be involved in PDAC chemoresistance, a Gemcitabine (Gem) resistant (GR) cell line, MIA PaCa-2 GR, was created and assessed for its SSV levels and their potential association with GR. Cross-resistance was assessed in MIA-PaCa-2 GR cells to FIRINOX (5-fluorouracil (5-FU), irinotecan, and oxaliplatin). Once chemoresistance was confirmed, RT-qPCR was used to assess the expression of survivin splice variants (SSVs) in PDAC cell lines. To confirm the effect of SSVs on chemoresistance, we used siRNA to knockdown all SSVs or SSV 2ß. Results: The MIA PaCa-2 GR cell line was 40 times more resistant to Gem and revealed increased resistance to FIRINOX (5-fluorouracil (5-FU), irinotecan, and oxaliplatin); when compared to the parental MIA-PaCa-2 cells. RT-qPCR studies revealed an 8-fold relative expression increase in SSV 2ß and a 2- to 8-fold increase in the other five SSVs in the GR cells. Knockdown of all SSV or SSV 2ß only, using small inhibitory RNA (siRNA), sensitized the GR cells to Gem, indicating that these SSVs play a role in PDAC chemoresistance. Conclusion: These findings provide evidence for the potential role of SSV 2ß and other SSVs in innate and acquired PDAC chemoresistance. We also show that the expression of SSVs is not affected by the type of chemoresistance, therefore targeting survivin splice variants in combination with chemotherapy could benefit a wide range of patients.

8.
Trauma Surg Acute Care Open ; 6(1): e000608, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33490604

RESUMO

Recent military conflicts in Iraq and Afghanistan have resulted in the significant increase in blast-related traumatic brain injury (TBI), leading to increased Department of Defense interest in its potential long-term effects ranging from the mildest head injuries termed subconcussive trauma to the most debilitating termed chronic traumatic encephalopathy (CTE). Most patients with mild TBI will recover quickly while others report persistent symptoms called postconcussive syndrome. Repeated concussive and subconcussive head injuries result in neurodegenerative conditions that may hinder the injured for years. Fundamental questions about the nature of these injuries and recovery remain unanswered. Clinically, patients with CTE present with either affective changes or cognitive impairment. Genetically, there have been no clear risk factors identified. The discovery that microglia of the cerebral cortex discharged small extracellular vesicles in the injured and adjacent regions to a TBI may soon shed light on the immediate impact injury mechanisms. The combination of neuroimaging and advanced research techniques may, one day, fill critical knowledge gaps and lead to significant TBI research and treatment advancements.

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