Explore the vast range of titles available.

Background Hepatocellular carcinoma (HCC) stands as the sixth most prevalent cancer globally, presenting a substantial health challenge, particularly due to late-stage diagnoses that limit treatment effectiveness. Sorafenib, a multi-kinase inhibitor, is the primary chemotherapeutic agent for advanced HCC, but it only extends survival by 2–3 months. However, drug resistance remains a major clinical challenge, necessitating the exploration of new molecular mechanisms, including the role of microRNAs (miRNAs) in sorafenib resistance. In this study, we aimed to identify miRNAs within exosomes derived from sorafenib-resistant HCC cells to elucidate the molecular mechanisms underlying resistance. Methods Sorafenib-resistant cells were generated by culturing the human HCC cell line Huh7 in a medium containing 20 µM sorafenib for six months. Exosomes were isolated from the conditioned medium 24 h before cell harvest using exosome-depleted serum medium. miRNA sequencing and western blotting were used to analyze the expression profiles of exosomal miRNAs and proteins, respectively. pH measurement was performed to assess pH changes in response to sorafenib treatment and miRNA modulation. Results A total of 180 exosomal miRNAs were found to be dysregulated between sorafenib-treated control Huh7 (Huh7S) and sorafenib-resistant Huh7 (Huh7RS) cells, as well as between untreated control Huh7 and Huh7RS cells. Among these, miR-6126 was significantly downregulated in Huh7RS cells compared to Huh7S cells. Functional studies using 2-dimensional (D) and 3D cell culture systems revealed that miR-6126 overexpression reduced sorafenib resistance in Huh7RS cells, while its inhibition increased resistance in Huh7 cells. miR-6126 downregulated key proteins involved in cancer stem cell maintenance, such as CD44 and HK2. Furthermore, the pH level was elevated in cells overexpressing miR-6126 following sorafenib treatment, whereas inhibiting miR-6126 resulted in a lower pH. Conclusions Exosomal miR-6126 plays a pivotal role in sorafenib resistance and tumorigenesis, highlighting its potential as a novel therapeutic target for overcoming drug resistance in HCC.

Background Hepatocellular carcinoma (HCC) is the leading cause of cancer-related deaths worldwide. The only drug currently approved for clinical use in the treatment of advanced HCC is sorafenib. However, many patients with HCC show reduced sensitivity to sorafenib during treatment. SIRT3, a member of the mammalian sirtuin family, is a tumor suppressor in certain tumor types. However, only few studies have investigated the effects of SIRT3 on tumor prognosis and sorafenib sensitivity in patients with HCC. Here, we aimed to investigate the correlation between SIRT3 expression and glucose metabolism and proliferation in HCC and discover effective compounds that increase endogenous SIRT3 modulation effect of sorafenib. Methods To determine the correlation between SIRT3 and glucose related proteins, immunostaining was performed with liver cancer tissue using various antibodies. To investigate whether the expression of SIRT3 in HCC is related to the resistance to sorafenib, we treated sorafenib after the modulation of SIRT3 levels in HCC cell lines (overexpression in Huh7, knockdown in HepG2). We also employed PD0332991 to modulate the SIRT3 expression in HCC cell and conducted functional assays. Results SIRT3 expression was downregulated in high glycolytic and proliferative HCC cells of human patients, xenograft model and HCC cell lines. Moreover, SIRT3 expression was downregulated after sorafenib treatment, resulting in reduced drug sensitivity in HCC cell lines. To enhance the anti-tumor effect of sorafenib, we employed PD0332991 (CDK4/6-Rb inhibitor) based on the correlation between SIRT3 and phosphorylated retinoblastoma protein in HCC. Notably, combined treatment with sorafenib and PD0332991 showed an enhancement of the anti-tumor effect in HCC cells. Conclusions Our data suggest that the modulation of SIRT3 by CDK4/6 inhibition might be useful for HCC therapy together with sorafenib, which, unfortunately, has limited efficacy and whose use is often associated with drug resistance.

Somatostatin analogs, which are used to treat neuroendocrine tumors, inhibit hormone secretion or promote tumor shrinkage; however, their efficacy varies between patients, possibly because of differential expression of somatostatin receptors (SSTRs) in tumors. In this study, we evaluated the regulatory mechanism underlying the expression of SSTR2, the main octreotide target. Thirty miRNAs were found to be dysregulated in neuroendocrine cells (INS-1 cells) incubated with octreotide compared to that in placebo-treated cells. Among the upregulated miRNAs, miR-16-5p was elevated after short-term octreotide treatment. We conducted in vitro experiments to determine whether the expression of miR-16-5p was associated with the regulation of SSTR2 expression and affected octreotide sensitivity in INS-1 cells. Overexpression of miR-16-5p by transfected mimics induced upregulation of SSTR2 expression. Additionally, the expression of miR-16-5p further enhanced octreotide-induced reduction in cell proliferation in both two- and three-dimensional culture of INS-1 cells. Thus, our results reveal the mechanism underlying SSTR2 expression regulation and may aid in developing therapeutic approaches for enhancing the response to octreotide, particularly in patients unresponsive to SSTR2-targeted somatostatin analog treatment.

Hepatocellular carcinoma (HCC) is the fifth leading cause of cancer-related mortality worldwide. Programmed cell death ligand-1 (PD-L1) is an immune checkpoint protein that binds to programmed cell death-1 (PD-1), which is expressed in activated T cells and other immune cells and has been employed in cancer therapy, including HCC. Recently, PD-L1 overexpression has been documented in treatment-resistant cancer cells. Sorafenib is a multikinase inhibitor and the only FDA-approved treatment for advanced HCC. However, several patients exhibit resistance to sorafenib during treatment. This study aimed to assess the effect of glucose deprivation on PD-L1 expression in HCC cells. We used PD-L1-overexpressing HepG2 cells and IFN-γ-treated SK-Hep1 cells to explore the impact of glycolysis on PD-L1 expression. To validate the correlation between PD-L1 expression and glycolysis, we analyzed data from The Cancer Genome Atlas (TCGA) and used immunostaining for HCC tissue analysis. Furthermore, to modulate PD-L1 expression, we treated HepG2, SK-Hep1, and sorafenib-resistant SK-Hep1R cells with rapamycin. Here, we found that glucose deprivation reduced PD-L1 expression in HCC cells. Additionally, TCGA data and immunostaining analyses confirmed a positive correlation between the expression of hexokinase II (HK2), which plays a key role in glucose metabolism, and PD-L1. Notably, rapamycin treatment  decreased the expression of PD-L1 and HK2 in both high PD-L1-expressing HCC cells and sorafenib-resistant cells. Our results suggest that the modulation of PD-L1 expression by glucose deprivation may represent a strategy to overcome PD-L1 upregulation in patients with sorafenib-resistant HCC.

Imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is used to determine sites of abnormal glucose metabolism to predict high tumor grade, metastasis, and poor patient survival. However, not all tumors with increased 18F-FDG uptake show aggressive tumor biology, as evident from the moderate correlation between metastasis and high FDG uptake. We hypothesized that metastasis is likely attributable to the complexity and heterogeneity of the cancer microenvironment. To identify the cancer microenvironment that induces the epithelial-mesenchymal transition (EMT) process, tumor areas of patients with HCC were analyzed by immunostaining. Our data demonstrated the induction of EMT process in HCC cells with low proliferation under hypoxic conditions. To validate our finding, among HCC cell lines, HepG2 cells with highly increased expression of HIF1α under hypoxia were employed in vitro and in vivo . Major changes in EMT-associated protein expression, such as the up-regulation of N-cadherin and snail/slug are associated with decreased proliferation-related protein (PCNA) caused by glucose deprivation under hypoxia. Indeed, PCNA knockdown-HepG2 cells under hypoxia showed the induction of more EMT process compare to the control. Thus, HCC cells with low proliferative potential under glucose-deprived and hypoxic conditions show high probability for induced EMT process and promote cell invasion. This study investigates reasons as to why an EMT process cannot fully be predicted. Our observations indicate that rather than analyzing a single factor, an integrated analysis of hypoxia with low glucose metabolism and low cell proliferation might be helpful to predict the potential impact on induction of EMT process and promotion of cell invasion.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Sorafenib, a multi-kinase inhibitor, is the first-line therapy for advanced HCC. However, long-term exposure to sorafenib often results in reduced sensitivity and the development of resistance. Although various amino acids have been shown to contribute to cancer initiation and progression, little is known about the effects of histidine, a dietary essential amino acid that is partially taken up via histidine/large neutral amino acid transporter (LAT1), on cancer cells. In this study, we evaluated the effects of histidine on HCC cells and sensitivity to sorafenib. Remarkably, we found that exogenous histidine treatment induced a reduction in the expression of tumor markers related to glycolysis (GLUT1 and HK2), inflammation (STAT3), angiogenesis (VEGFB and VEGFC), and stem cells (CD133). In addition, LAT1 expression was downregulated in HCC tumor regions with high expression of GLUT1, CD133, and pSTAT3, which are known to induce sorafenib resistance. Finally, we demonstrated that combined treatment with sorafenib and histidine could be a novel therapeutic strategy to enhance the sensitivity to sorafenib, thereby improving long-term survival in HCC.

Acetyl-CoA synthetase 2 (ACSS2)-dependent acetate usage has generally been associated with tumorigenesis and increased malignancy in cancers under nutrient-depleted conditions. However, the nutrient usage and metabolic characteristics of the liver differ from those of other organs; therefore, the mechanism of ACSS2-mediated acetate metabolism may also differ in liver cancer. To elucidate the underlying mechanisms of ACSS2 in liver cancer and acetate metabolism, the relationships between patient acetate uptake and metabolic characteristics and between ACSS2 and tumor malignancies were comprehensively studied in vitro , in vivo and in humans. Clinically, we initially found that ACSS2 expression was decreased in liver cancer patients. Moreover, PET-CT imaging confirmed that lower-grade cancer cells take up more 11 C-acetate but less 18 F-fluorodeoxyglucose ( 18 F-FDG); however, this trend was reversed in higher-grade cancer. Among liver cancer cells, those with high ACSS2 expression avidly absorbed acetate even in a glucose-sufficient environment, whereas those with low ACSS2 expression did not, thereby showing correlations with their respective ACSS2 expression. Metabolomic isotope tracing in vitro and in vivo revealed greater acetate incorporation, greater lipid anabolic metabolism, and less malignancy in high-ACSS2 tumors. Notably, ACSS2 downregulation in liver cancer cells was associated with increased tumor occurrence in vivo. In human patient cohorts, patients in the low-ACSS2 subgroup exhibited reduced anabolism, increased glycolysis/hypoxia, and poorer prognosis. We demonstrated that acetate uptake by ACSS2 in liver cancer is independent of glucose depletion and contributes to lipid anabolic metabolism and reduced malignancy, thereby leading to a better prognosis for liver cancer patients. Acetyl-CoA Synthetase 2: A New Hope for Liver Cancer Prognosis Liver cancer patients with high amounts of Acetyl-CoA synthetase 2 (ACSS2), an enzyme that helps break down acetate, tend to have a better outlook than those with low amounts, according to a study by Kyung Hee Jung and team. The researchers discovered that high ACSS2 levels are linked with anabolic characteristics, reduced glycolysis, and lower hypoxia, which all point to less severe cancer. The study involved lab experiments, animal testing, and analysis of human patient data. The team also found a group of patients with very low ACSS2 levels who had especially bad outlooks. The results suggest that ACSS2 could be a potential indicator for liver cancer outlook and could assist in making treatment choices. This summary was initially drafted using artificial intelligence, then revised and fact-checked by the author.

HCC is well known for low glycolysis in the tumors, whereas hypoxia induces glycolytic phenotype and tumor progression. This study was conducted to evaluate the expression of SLCs in human HCCs and investigated whether extracellular nutrient administration related to SLCs in low-glycolytic HCC can prevent hypoxic tumor progression. SLCs expression was screened according to the level of glycolysis in HCCs. Then, whether extracellular nutrient treatment can affect hypoxic tumor progression, as well as the mechanisms, were evaluated in an in vitro cell line and an in vivo animal model. Low-glycolytic HCCs showed high SLC13A5/NaCT and SLC16A1/MCT1 but low SLC2A1/GLUT1 and HIF1α/HIF1α expression. Especially, high SLC13A5 expression was significantly associated with good overall survival in the Cancer Genome Atlas (TCGA) database. In HepG2 cells with the highest NaCT expression, extracellular citrate treatment upon hypoxia induced HIF1α degradation, which led to reduced glycolysis and cellular proliferation. Finally, in HepG2-animal models, the citrate-treated group showed smaller tumor with less hypoxic areas than the vehicle-treated group. In patients with HCC, SLC13A5/NaCT is an important SLC, which is associated with low glycolysis and good prognosis. Extracellular citrate treatment induced the failure of metabolic adaptation to hypoxia and tumor growth inhibition, which can be a potential therapeutic strategy in HCCs.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein (NP) participates in viral genome packaging and abundantly produced when infected. In this work, SPR biosensor for the detection of SARS-CoV-2 in viral fluid using Fv-antibodies with the binding affinity to nucleocapsid protein (NP) of SARS-CoV-2. The F V -antibodies with a specific binding activity to the SARS-CoV-2 NP were screened using the F V -antibody library, which was expressed on the outer membrane of E. coli . F V -antibodies comprised three complementarity-determining regions (CDRs) and four frame regions (FRs) of the heavy chain at the binding pocket of IgG. The F V -antibody library was prepared by performing site-directed mutagenesis and by using the autodisplay technology; F V -antibodies with specific binding activities to the nucleocapsid protein (NP) of SARS-CoV-2 were screened using NP-immobilized magnetic beads. First, E. coli isolates with the target F V -antibody were screened, and the binding affinity (K D ) was estimated for the screened E. coli clones using FACS analysis. Then, the outer membrane (OM) of the screened E. coli clones with autodisplayed Fv-antibodies was obtained and layered on an SPR biosensor, and the binding curves of four different coronavirus (CoV) culture fluids, SARS-CoV-2, SARS-CoV, MERS-CoV, and CoV strain 229E, were compared. Finally, the F V -antibodies of the screened E. coli clones were synthesized as peptides (11 amino acid residues), and the binding constants (K D ) to NP as well as the binding curves of the CoV strains in culture fluids were estimated. Using docking simulation, binding sites and interaction types between NP and each synthetic peptide were investigated. Graphical Abstract

Introduction: In several fields, the process of fusing multiple two-dimensional (2D) closed lines is an important step. For instance, this is fundamental in histology and oncology in general. The treatment of a tumor consists of numerous steps and activities. Among them, segmenting the cancer area, that is, the correct identification of its spatial location by the segmentation technique, is one of the most important and at the same time complex and delicate steps. The difficulty in deriving reliable segmentations stems from the lack of a standard for identifying the edges and surrounding tissues of the tumor area. For this reason, the entire process is affected by considerable subjectivity. Given a tumor image, different practitioners can associate different segmentations with it, and the diagnoses produced may differ. Moreover, experimental data show that the analysis of the same area by the same physician at two separate timepoints may result in different lines being produced. Accordingly, it is challenging to establish which contour line is the ground truth. Methods: Starting from multiple segmentations related to the same tumor, statistical metrics and computational procedures could be exploited to combine them for determining the most reliable contour line. In particular, numerous algorithms have been developed over time for this procedure, but none of them is validated yet. Accordingly, in this field, there is no ground truth, and research is still active. Results: In this work, we developed the Two-Dimensional Segmentation Fusion Tool ( TDSFT ), a user-friendly tool distributed as a free-to-use standalone application for MAC , Linux , and Windows , which offers a simple and extensible interface where numerous algorithms are proposed to “compute the mean” (i.e., the process to fuse, combine, and “average”) multiple 2D lines. Conclusions: The TDSFT can support medical specialists, but it can also be used in other fields where it is required to combine 2D close lines. In addition, the TDSFT is designed to be easily extended with new algorithms thanks to a dedicated graphical interface for configuring new parameters. The TDSFT can be downloaded from the following link: https://sourceforge.net/p/tdsft .