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Frontiers in Bioscience (Landmark... Jun 2024Gastric cancer (GC) is a leading cause of cancer-associated death worldwide. Its molecular mechanisms, especially concerning autophagy and various signaling pathways,...
BACKGROUND
Gastric cancer (GC) is a leading cause of cancer-associated death worldwide. Its molecular mechanisms, especially concerning autophagy and various signaling pathways, are not fully understood. Fatty Acid Binding Protein 6 () and RE1 Silencing Transcription Factor () emerge as potential key players in this context. This study sought to analyze the functional relationship of and concerning autophagy and their implications on the Akt/mTOR signaling pathway within GC cells.
METHODS
A comprehensive bioinformatics approach was used to identify key prognostic markers in GC. The effects of and on autophagy along with Akt/mTOR signaling pathways were analyzed by techniques including Western blotting (WB), flow cytometry, Transwell assay, dual luciferase reporter assay, and others.
RESULTS
was identified as overexpressed in GC, linked with poor prognosis. silencing reduces GC cell proliferation, induces S- and G2-phase arrest, and downregulates cyclins CDK2 and CDK4. It also inhibited GC cell invasion/migration and autophagy, effects that were counteracted by MG132. When combined with PI3K inhibitor LY294002c, knockdown showed synergistic anti-proliferative effects, modulating the Akt/mTOR pathway. Besides, the transcription factor has been shown to directly regulate expression, affecting autophagy and the Akt/mTOR signaling pathway in a -dependent manner.
CONCLUSIONS
positively regulates autophagy and negatively affects the Akt/mTOR signaling pathway in GC cells in a FABP6-dependent manner, providing valuable insights into regulatory networks involving and .
Topics: Humans; Stomach Neoplasms; TOR Serine-Threonine Kinases; Autophagy; Proto-Oncogene Proteins c-akt; Signal Transduction; Cell Line, Tumor; Fatty Acid-Binding Proteins; Cell Proliferation; Gene Expression Regulation, Neoplastic
PubMed: 38940038
DOI: 10.31083/j.fbl2906212 -
Frontiers in Bioscience (Landmark... Jun 2024L-Theanine, a nonproteinogenic amino acid derived from green tea, is being recognized as an anti-cancer candidate. However, it's roles in the development of cancer...
BACKGROUND
L-Theanine, a nonproteinogenic amino acid derived from green tea, is being recognized as an anti-cancer candidate. However, it's roles in the development of cancer chemoresistance is still unknown and the molecular mechanism is urgently to be explored.
METHODS
The effects of L-Theanine on lung cancer chemoresistance were validated by Cell Counting Kit-8 (CCK-8) assay, transwell assay, and tumor spheroid formation assay; the expression of proteins was detected by using polymerase chain reaction (PCR) and western blotting. RNA-sequencing (RNA-seq) and bioinformatics analysis were used to identify differentially expressed genes induced by L-Theanine. knockdown and overexpression were constructed by using a lentivirus-mediated transfection system.
RESULTS
L-Theanine improved the chemoresistance to -diamminedichloroplatinum (DDP) and inhibited stemness of DDP-resistant lung cancer cells but not non-resistant lung cancer cells. The results from RNA-seq analysis showed that STAT3/NOTCH1 pathway was a potential dominant signaling involved in L-Theanine improving the chemoresistance in DDP-resistant lung cancer. Mechanistically, L-Theanine impeded migration and stemness activation of DDP-resistant lung cancer cells via regulating the expression of STAT3/NOTCH1/BMAL1 signaling-induced stemness markers as well as inhibiting the expression levels of drug resistance-related genes. In addition, a combination of L-Theanine and Stat3 blockade synergistically improved the chemoresistance in DDP-resistant lung cancer.
CONCLUSION
L-Theanine improves the chemoresistance by regulating STAT3/NOTCH1/BMAL1 signaling, reducing stemness, and inhibiting the migration of DDP-resistant lung cancer cells. The finding might provide some evidence for therapeutic options in overcoming the chemoresistance in cancers, including lung cancer.
Topics: Humans; Glutamates; Drug Resistance, Neoplasm; Lung Neoplasms; Cisplatin; STAT3 Transcription Factor; Signal Transduction; Receptor, Notch1; Cell Line, Tumor; ARNTL Transcription Factors; Antineoplastic Agents; Gene Expression Regulation, Neoplastic; A549 Cells; Cell Movement
PubMed: 38940036
DOI: 10.31083/j.fbl2906226 -
Frontiers in Bioscience (Landmark... May 2024Lung cancer is the primary cause of cancer-related deaths, with one of the highest incidence and mortality rates of all malignant tumors. Dysregulated expression of...
BACKGROUND
Lung cancer is the primary cause of cancer-related deaths, with one of the highest incidence and mortality rates of all malignant tumors. Dysregulated expression of DEPDC1B has been reported to occur in various tumor types. However, the functional implications of this alteration in lung adenocarcinoma (LUAD) and the underlying molecular mechanism remains unclear. In this study, we investigated the role and clinical significance of DEPDC1B in LUAD.
METHODS
The expression of DEPDC1B in LUAD and its relationship with prognosis were systematically evaluated in several publically available datasets. The effects of DEPDC1B knockdown on the proliferation and motility of LUAD cells were assessed using the JULI Stage Real-time Cell History Recorder, while the effect of knockdown on the cell cycle was studied by flow cytometry. Furthermore, RNA-Sequencing (RNA-Seq) analysis was conducted to identify the downstream target genes and pathways regulated by DEPDC1B. Correlations between the expression of DEPDC1B and immune cell infiltration, immunotherapy resistance, and chemoresistance were also examined. Additionally, molecular biological methods were used to explore the regulatory mechanism of B-Myb on DEPDC1B expression.
RESULTS
DEPDC1B was found to be upregulated in LUAD patients and this was associated with poor clinical outcomes. Knockdown of inhibited cell growth, migration and motility, as well as cell cycle progression. Knockdown also resulted in the down-regulation of several downstream genes, including , , and , as well as the inactivation of multiple critical pathways, such as the ERK and PI3K-AKT pathways. Analysis of the tumor immuno-environment in LUAD revealed that high DEPDC1B expression was associated with an abundance of activated CD4+ memory T cells, M0 macrophages, M1 macrophages, and CD8+ T cells. Moreover, these tumors responded poorly to immunotherapy. Analysis of chemo-drug sensitivity showed that LUADs with high DEPDC1B expression were more responsive to frontline chemotherapeutic drugs such as Vinorelbine, Cisplatin, and Etoposide. Additionally, mechanistic investigations revealed that DEPDC1B is a direct target gene of B-Myb, and that its knockdown attenuated the proliferation and motility effects of B-Myb.
CONCLUSIONS
In summary, our findings indicate that DEPDC1B is a critical regulator during the malignant progression of LUAD. DEPDC1B could therefore be a promising prognostic marker and therapeutic target in LUAD diagnosis and treatment.
Topics: Humans; Adenocarcinoma of Lung; GTPase-Activating Proteins; Lung Neoplasms; Cell Proliferation; Cell Movement; Gene Expression Regulation, Neoplastic; Cell Line, Tumor; Disease Progression; Cell Cycle Proteins; Prognosis; Drug Resistance, Neoplasm; Male; Gene Knockdown Techniques; Signal Transduction; Neoplasm Proteins; Trans-Activators
PubMed: 38940035
DOI: 10.31083/j.fbl2906204 -
Frontiers in Bioscience (Landmark... Jun 2024Existing animal models for testing therapeutics in the skin are limited. Mouse and rat models lack similarity to human skin in structure and wound healing mechanism....
BACKGROUND
Existing animal models for testing therapeutics in the skin are limited. Mouse and rat models lack similarity to human skin in structure and wound healing mechanism. Pigs are regarded as the best model with regards to similarity to human skin; however, these studies are expensive, time-consuming, and only small numbers of biologic replicates can be obtained. In addition, local-regional effects of treating wounds that are closely adjacent to one-another with different treatments make assessment of treatment effectiveness difficult in pig models. Therefore, here, a novel nude mouse model of xenografted porcine hypertrophic scar (HTS) cells was developed. This model system was developed to test if supplying hypo-pigmented cells with exogenous alpha melanocyte stimulating hormone (α-MSH) will reverse pigment loss .
METHODS
Dyschromic HTSs were created in red Duroc pigs. Epidermal scar cells (keratinocytes and melanocytes) were derived from regions of hyper-, hypo-, or normally pigmented scar or skin and were cryopreserved. Dermal fibroblasts (DFs) were isolated separately. Excisional wounds were created on nude mice and a grafting dome was placed. DFs were seeded on day 0 and formed a dermis. On day 3, epidermal cells were seeded onto the dermis. The grafting dome was removed on day 7 and hypo-pigmented xenografts were treated with synthetic α-MSH delivered with microneedling. On day 10, the xenografts were excised and saved. Sections were stained using hematoxylin and eosin hematoxylin and eosin (H&E) to assess xenograft structure. RNA was isolated and quantitative real-time polymerase chain reaction (qRT-PCR) was performed for melanogenesis-related genes , , and .
RESULTS
The seeding of HTSDFs formed a dermis that is similar in structure and cellularity to HTS dermis from the porcine model. When hyper-, hypo-, and normally-pigmented epidermal cells were seeded, a fully stratified epithelium was formed by day 14. H&E staining and measurement of the epidermis showed the average thickness to be 0.11 ± 0.07 µm 0.06 ± 0.03 µm in normal pig skin. Hypo-pigmented xenografts that were treated with synthetic α-MSH showed increases in pigmentation and had increased gene expression of , , and compared to untreated controls (TYR: 2.7 ± 1.1 0.3 ± 1.1; TYRP1: 2.6 ± 0.6 0.3 ± 0.7; DCT 0.7 ± 0.9 0.3 ± 1-fold change from control; n = 3).
CONCLUSIONS
The developed nude mouse skin xenograft model can be used to study treatments for the skin. The cells that can be xenografted can be derived from patient samples or from pig samples and form a robust dual-skin layer containing epidermis and dermis that is responsive to treatment. Specifically, we found that hypo-pigmented regions of scar can be stimulated to make melanin by synthetic α-MSH .
Topics: Animals; Mice, Nude; Cicatrix, Hypertrophic; Mice; Disease Models, Animal; Swine; alpha-MSH; Humans; Skin; Fibroblasts; Melanocytes; Keratinocytes; Transplantation, Heterologous; Wound Healing; Skin Pigmentation
PubMed: 38940034
DOI: 10.31083/j.fbl2906230 -
Frontiers in Bioscience (Landmark... Jun 2024The senescence marker protein 30 (SMP30) is a calcium-binding protein whose expression decreases with age, and is closely associated with hepatocellular carcinoma (HCC)...
BACKGROUND
The senescence marker protein 30 (SMP30) is a calcium-binding protein whose expression decreases with age, and is closely associated with hepatocellular carcinoma (HCC) development. The primary goal of this study was to examine the mechanistic effect of SMP30 on HCC migration and invasion.
METHODS
Bioinformatic and immunohistochemical approaches were used to examine the expression of SMP30 in HCC tissues and its relationship to patient survival. We investigated the effects of SMP30 expression on HCC cell proliferation, migration, invasion, and cell cycle dynamics. cDNA microarray technology was used to determine the gene expression profile of SK-Hep-1 cells following recombinant SMP30 overexpression to identify genes downstream of SMP30 that regulate HCC cell migration and invasion. We identified SMP30 interacting proteins by affinity purification-mass spectrometry (AP-MS) and co-immunoprecipitation/western blotting (COIP-WB).
RESULTS
SMP30 expression was lower in HCC tissues compared with normal liver tissues, and its expression positively correlated with overall survival in HCC patients. Additionally, SMP30 overexpression effectively blocked the migratory and invasive properties of SK-Hep-1 cells, but did not affect either proliferation rates or cell cycle. cDNA microarray results confirmed that many of the differentially expressed genes identified are involved in the process of epithelial-mesenchymal transition (EMT). AP-MS and COIP-WB experiments confirmed that Rho-associated protein kinase 1 (ROCK1) interacts with SMP30 in SK-Hep-1 cells, and ROCK1 is known to intimately regulate the EMT process.
CONCLUSION
SMP30 inhibits HCC metastasis by influencing the expression of EMT-related proteins after interacting with ROCK1.
Topics: Humans; rho-Associated Kinases; Epithelial-Mesenchymal Transition; Carcinoma, Hepatocellular; Liver Neoplasms; Calcium-Binding Proteins; Neoplasm Invasiveness; Cell Line, Tumor; Cell Movement; Cell Proliferation; Intracellular Signaling Peptides and Proteins; Male; Female; Gene Expression Regulation, Neoplastic
PubMed: 38940025
DOI: 10.31083/j.fbl2906214 -
Frontiers in Bioscience (Scholar... May 2024The ETS transcription factor PU.1 plays an essential role in blood cell development. Its precise expression pattern is governed by cis-regulatory elements (CRE) acting... (Review)
Review
The ETS transcription factor PU.1 plays an essential role in blood cell development. Its precise expression pattern is governed by cis-regulatory elements (CRE) acting at the chromatin level. CREs mediate the fine-tuning of graded levels of , deviations of which can cause acute myeloid leukemia. In this review, we perform an in-depth analysis of the regulation of expression in normal and malignant hematopoiesis. We elaborate on the role of trans-acting factors and the biomolecular interplays in mediating local chromatin dynamics. Moreover, we discuss the current understanding of CRE bifunctionality exhibiting enhancer or silencer activities in different blood cell lineages and future directions toward gene-specific chromatin-targeted therapeutic development.
Topics: Humans; Hematopoiesis; Proto-Oncogene Proteins; Trans-Activators; Cell Lineage; Animals; Transcription, Genetic; Gene Expression Regulation; Leukemia, Myeloid, Acute; Chromatin
PubMed: 38939973
DOI: 10.31083/j.fbs1602010 -
Oncology Letters Aug 2024Thymic epithelial tumors (TETs) are rare and the major symptoms are not obvious until the tumor progresses to a relatively large size and compresses the surrounding...
Thymic epithelial tumors (TETs) are rare and the major symptoms are not obvious until the tumor progresses to a relatively large size and compresses the surrounding organs. As its growth is aggressive and it metastasizes to distant organs, it is important to find novel effective therapies. Lenvatinib, a vascular endothelial growth factor receptor (VEGFR) inhibitor, is approved as a drug therapy for thymic carcinoma (TC); however, although it is a molecular targeted therapy, there are no obvious predictors of therapeutic efficacy. The present study aimed to assess the association between clinicopathological factors and the protein expression of VEGFR, which is associated with tumor aggressiveness and the efficacy of VEGFR inhibitors. The VEGFR-2 protein expression was evaluated in 144 patients with TETs who underwent surgical resection. The present study assessed whether the expression of VEGFR-2 protein was associated with TET classification and pathological stage, progression-free survival and overall survival (OS). A total of 94 cases (65.2%) were positive for VEGFR-2 protein. The expression of VEGFR-2 was higher in the more aggressive type B3 thymoma and TC (88.5%) than in types A, AB, B1 and B2 thymoma (60.2%). The 5-year OS rate for the overall population was 53.1%. The 5-year OS rates of patients with negative VEGFR-2 staining score values (66.5%) were significantly longer than in patients with positive VEGFR-2 staining score values (42.5%; P=0.000078). Furthermore, the pathological stage was the only factor significantly associated with OS in multivariate analysis. The results of the present study suggest the possibility that the indications for VEGF inhibitor therapy could be extended to type B3 thymoma.
PubMed: 38939624
DOI: 10.3892/ol.2024.14516 -
Journal of Conservative Dentistry and... May 2024The purpose of this study was to evaluate the immunohistochemical effect of hyaluronic acid (HA) on the mineralization rate of the reparative dentin when it is used as a...
OBJECTIVE
The purpose of this study was to evaluate the immunohistochemical effect of hyaluronic acid (HA) on the mineralization rate of the reparative dentin when it is used as a mixing medium with mineral trioxide aggregate (MTA).
MATERIALS AND METHODS
Direct pulp capping (DPC) was performed on 90 teeth from 10 dogs that had been experimentally exposed. The exposed pulps were divided into three groups according to the mixing medium with MTA: Group I: MTA + distilled water (control group), Group II: MTA + hybrid cooperative complex HA (HCC-HA), Group III: MTA + high molecular weight HA (HMW-HA). After pulp capping, all cavities were restored with final restoration. The dogs were divided randomly into five groups (two dogs each) according to the evaluation periods (7, 14, 21, 30, and 60) days. At the end of the study, the dogs were euthanized, and the sampled teeth were processed for immunohistochemical investigation.
RESULTS
Both types of HA (HCC-HA, HMW-HA) showed an increase in the expression of alkaline phosphatase (ALP) at a higher rate than using distilled water with MTA.
CONCLUSIONS
Within the limitations of this study, HA proved to be an effective additive to MTA for DPC.
PubMed: 38939541
DOI: 10.4103/JCDE.JCDE_88_24 -
Frontiers in Oncology 2024Field cancerization is suggested to arise from imbalanced differentiation in individual basal progenitor cells leading to clonal expansion of mutant cells that...
INTRODUCTION
Field cancerization is suggested to arise from imbalanced differentiation in individual basal progenitor cells leading to clonal expansion of mutant cells that eventually replace the epithelium, although without evidence.
METHODS
We performed deep sequencing analyses to characterize the genomic and transcriptomic landscapes of field change in two patients with synchronous aerodigestive tract tumors.
RESULTS
Our data support the emergence of numerous genetic alterations in cancer-associated genes but refutes the hypothesis that founder mutation(s) underpin this phenomenon. Mutational signature analysis identified defective homologous recombination as a common underlying mutational process unique to synchronous tumors.
DISCUSSION
Our analyses suggest a common etiologic factor defined by mutational signatures and/or transcriptomic convergence, which could provide a therapeutic opportunity.
PubMed: 38939336
DOI: 10.3389/fonc.2024.1272432 -
Frontiers in Oncology 2024Risk stratification and molecular targeting have been key to increasing cure rates for pediatric cancers in high-income countries. In contrast, precise diagnosis in...
Risk stratification and molecular targeting have been key to increasing cure rates for pediatric cancers in high-income countries. In contrast, precise diagnosis in low-resource settings is hindered by insufficient pathology infrastructure. The Global HOPE program aims to improve outcomes for pediatric cancer in Sub-Saharan Africa (SSA) by building local clinical care and diagnostic capacity. This study aimed to assess the feasibility of implementing molecular assays to improve leukemia diagnoses in SSA. Custom NanoString nCounter gene fusion assays, previously validated in the US, were used to test samples from suspected leukemia patients. The NanoString platform was chosen due to relatively low cost, minimal technical and bioinformatics expertise required, ability to test sub-optimal RNA, and rapid turnaround time. Fusion results were analyzed blindly, then compared to morphology and flow cytometry results. Of 117 leukemia samples, 74 were fusion-positive, 30 were negative, 7 were not interpretable, and 6 failed RNA quality. Nine additional samples were negative for leukemia by flow cytometry and negative for gene fusions. All 74 gene fusions aligned with the immunophenotype determined by flow cytometry. Fourteen samples had additional information available to further confirm the accuracy of the gene fusion results. The testing provided a more precise diagnosis in >60% of cases, and 9 cases were identified that could be treated with an available tyrosine kinase inhibitor, if detected at diagnosis. As risk-stratified and targeted therapies become more available in SSA, implementing this testing in real-time will enable the treatment of pediatric cancer to move toward incorporating risk stratification for optimized therapy.
PubMed: 38939333
DOI: 10.3389/fonc.2024.1426638