Introduction
Hepatocellular carcinoma is the fifth most common cancer worldwide and the second leading cause of cancer-related death for men worldwide, with 905,677 new cases and 830,180 new deaths of liver cancer in 2020. In China, despite the decline in the prevalence of HBV and HCV, the increase of excess body weight and diabetes have still stabilized the incidence rates of hepatocellular carcinoma at a high level [
1].
Cells undergo metabolic reprogramming during carcinogenesis, including dysregulation of glycolysis, glutamine addiction, reprogramming of lipid metabolism, and more. Targeting cancer metabolism is believed to have promising anticancer effects [
2]. High demand for acquiring metabolism resources lead to fierce nutrient competition in the tumor microenvironment. With greater capacity to consumpt glucose, tumor cells can build up a glucose-depleted environment to restrict T cells function, inducing their dampened mTOR activity, glycolytic capacity, and IFN-g production. T cell dysfunction or hyporesponsiveness allow tumor immune escape [
3]. Ketogenic diet or exogenous supplements can induce ketosis, significantly reduce blood glucose and insulin, modulate tumor microenvironment, as well as slow down tumor progression and potential symptom burden [
4].
Glucose, as the most important energy source of the cell, plays an extremely important role in the progression of the tumor cells [
5]. Blood glucose level could be directly correlated with tumor growth [
6]. ‘ Warburg effect’ refers to an important change in the glucose metabolism of tumor cells [
7]. Glycolysis of tumor cells is active even under aerobic conditions, showing high glucose uptake rate, high lactic acid content of the metabolites, and high ratio of glycolysis of the cancer cells to meet the various metabolic needs of the cells. It requires a large amount of the glucose transport from the tissue fluid into the cell, which is mainly mediated through the different glucose transporters (GLUTs). At present, there are 14 members belonging to this family, among which GLUT1 is the most important [
8], with two domains constitute a typical inward conformation [
9]. Since tumor cells need to express a great quantity of GLUT1 to meet their huge energy needs, GLUT1 expression in a variety of tumors is increased, such as that of lung cancer, hepatocellular carcinoma, gastric cancer and colorectal cancer [
10‐
13]. Kurahara et al. found that the prognosis of patients with pancreatic ductal adenocarcinoma was directly related to the expression of GLUT1 [
14]. Because of the importance of GLUT1 in the regulation of metabolism of tumor cells, drug targeting GLUT1 to regulate the metabolism could be prominent in cancer therapy.
YAP, also known as YAP1, is a transcription regulator of the Hippo pathway and hasimportant biological properties in cell proliferation, mature cells dedifferentiation, tumorigenesis and reprogramming of cellular metabolism [
15]. When the pathway is activated, YAP accumulates in the nucleus and the transcriptional co-activators of YAP and TAZ are recruited to target site by TEAD. YAP/TAZ/TEAD and activator protein-1 form a complex which promotes the expression of target genes [
16]. Another recent study has also proposed a new model in which YAP/TAZ is recruited to target genomic regions by a complex of AP-1, STAT3, and TEAD proteins [
17]. The overexpression of YAP in the liver of transgenic animals can induce the proliferation of mature hepatocytes and ultimately lead to a four-fold increase in liver mass [
18]. Its overexpression can also cause hyperproliferation of and depressed differentiation of neural progenitor cells [
19]. YAP has been detected in late-stage ovarian, colon, gastric, liver, esophageal and lobular type of invasive breast cancers to foster their proliferation, progression and migration [
20]. In recent years, studies have found that YAP is an emerging node that coordinates cell nutrition and tissue homeostasis, and participates in the regulation of cell metabolism such as glycolysis, lipogenesis, and glutaminolysis [
21,
22].
WZ35 was synthesized by our team [
23], which can significantly affect the growth of gastric cancer [
24], hepatocellular carcinoma [
25] and breast cancer [
26]. In this article, we further found that WZ35 could negatively regulate the metabolism of liver cancer cells mediated through GLUT1. The relationship between YAP and GLUT1 remains unclear. Andrew G Cox et al. have used zebrafish embryos as a model to prove YAP regulates the expression of GLUT1 and thus induces the regeneration of organs [
27]. But the effect on the metabolism and regulation mechanism remains to be further explored.
In this report, we found a novel small molecule glycolysis inhibitor WZ35 that could inhibit the intake of glucose. We identified new role of GLUT1-YAP on the prognosis of liver cancer patients. Further experiments demonstrated glucose intake inhibition inducing metabolic reprogramming and thereby suppressing the proliferation of liver cancer cells.
Material and methods
Reagents
Curcumin obtained from Sigma (MO, USA). WZ35, a monocarbonyl curcumin analog, was prepared as described in prior studies [
28]. Cell Counting Kit-8 (CCK-8) and horseradish peroxidase (HRP)-conjugated anti-rabbit and anti-mouse IgG and N-acetyl-l-cysteine (NAC) were purchased from Beyotime (Haimen, China). Cell Apoptosis DAPI Detection Kit, DCFH-DA ROS detection kit, and pEGFP-hYAP 1 were obtained from Addgene (Shanghai, China). A Hippo Signaling Antibody Sampler Kit (#8579), anti-YAP(#14074S), anti-Cleaved caspase 3 (#9661), anti-Bax (#2774), anti-Bcl-2 (#2870), anti-E-cadherin (#8834S), anti-GLUT1 (#73015), anti-N-cadherin (#13116S), anti- Histone H3 (#9715S) and anti-GAPDH (#D16H11) were purchased from Cell Signaling Technology (USA) for Western blot and IHC. Anti-Cyr61 (Sc-374129), anti-CTGF (Sc-365970) were purchased from Santa Cruz Biotechnology (USA) for Western blot. Anti-Tublin (ac008) was purchased from Abclonal for Western blot.
Cell culture
The human liver cancer cell lines including HCCLM3, HepG2 and Huh7 were obtained from the Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences. The cells were grown using Dulbecco's Modified Eagle's Medium (DMEM) containing 10% FBS (Life Technologies) and penicillin/streptomycin at 37 °C in a humidified 5% CO2 incubator.
Patient samples
110 matched liver cancer samples and precancerous control tissues were isolated from untreated patients at the Department of Hepatopancreatobiliary Surgery of the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China, between 2010 and 2014. They were separated into two different portions, with one portion being used for routine histopathological examinations, and the rest being snap-frozen and stored at −80 °C for future studies. Liver cancer was pathologically confirmed in all patients, with tumors staging being determined based upon the AJCC/UICC (Union for International Cancer Control/American Joint Committee on Cancer) and WHO classification. The Board and Ethical Committee of the First Affiliated Hospital of Wenzhou Medical University approved this study (ID number: wydw2019-0446), and all the patients provided written informed consent.
The GENE EXPRESSION OMNIBUS (GEO) database was searched using the terms "gene expression", "hepatocellular carcinoma", and "Homo sapiens". We selected the GSE14520 dataset as it met the quality control and the sample size criteria. The R software (version.4.2.0) limma package was used for normalization. Based on quality filtering, two healthy control microarray samples were excluded, while the remaining 486 microarrays (22 liver cancer samples, 19 adjacent control samples based on the GPL571 platform and 225 liver cancer samples, 220 adjacent control samples based on the GPL3921 platform were retained for analysis. The RStudio Limma package was used to identify the differentially expressed genes (adjusted
P < 0.05 and | logFC (Fold Change) |≥ 0.5), after which probe names were converted to gene names. The ggplot2 package was used to visualize differences in gene expression between the samples, with appropriate functions also being used to draw the boxplots, survival curves, and volcano plots in R software (version.4.2.0). To reveal the potential biological functions and underlying mechanisms of genes, we used the R package “clusterProfiler” to analyze Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genes (KEGG) term enrichment of the target genes GO terms, including biological processes (BPs), cellular components (CCs), molecular functions (MFs), and KEGG pathways with adjusted
P < 0.05, were considered statistically significant. JASPAR [
29] and USCS [
30] were used to predicted binding sites, conservation and histone modification.
Cell proliferation assay
Liver cancer cells were plated in 96-well plates (8 × 103/well) overnight, after which they were untreated or treated with curcumin (10 μg/mL), WZ35 (10 μg/mL), NAC (5 mM). For some experiments, a range of drug concentrations (0, 5, 10, 20, and 40 μg/mL) were used instead. WZ35 and curcumin were prepared using 0.03% DMSO; NAC was prepared in PBS and diluted using complete media. The CCK-8 kit was used to measure the viability with absorbance at 450 nm being quantified via microplate reader (Spectramax m5, Molecular Devices).
HCCLM3 cells were plated in 6-well plates (5,000/well) with curcumin (1 μg/mL), WZ35 (1 μg/mL), and/or NAC (5 mM). The plate incubated until individual colonies were formed containing approximately 50 cells. The cells were then washed in PBS, fixed for 20 min with methanol, stained for 15 min with crystal violet, washed with distilled water, and colonies were counted using the ImageJ software.
DAPI staining for cells
Apoptosis was measured by plating HCCLM3 cells in 6-well plates overnight (5 × 105/well). The cells were then treated using WZ35 or curcumin (both 10 cg/mL) for 18 h, after which they were washed using PBS, fixed for 15 min in 4% paraformaldehyde (PFA), and stained for 15 min with 4',6-diamidino-2-phenylindole (DAPI) (400 μL). The cells were thereafter imaged via microscope (NIKON, Japan) with 100 magnification. Compared to normal cells, cells undergoing apoptosis presented enhanced DAPI fluorescence for condensed nuclear chromatin, which can be individually identified with ImageJ software. Apoptosis rate was calculated by the percentage of condensation nuclear identified by ImageJ.
Western blotting
Radio immunoprecipitation assay (RIPA) lysis buffer obtained from Beyotime (Haimen, China) was used to isolate the proteins from the cells or to homogenize the tumor tissues. The samples were then spun for 15 min at 12,000 rpm, and equal amounts of supernatant protein (10 μg/sample) were separated via sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) (8, 10 or 12%) prior to transfer onto a poly (1,1-difluoroethylene) (PVDF) membrane (Millipore, Burlington, MA, USA). The blots were blocked for 90 min using 5% skim milk in TRIS hydrochloride & Tween (TBST), followed by an overnight incubation with the various primary antibodies at 4 °C. After washing three times in TBST (10 min/wash), the blots were incubated for 1 h with horseradish peroxidase (HRP)-linked secondary antibodies (1:2000), after which they were washed again and protein bands were detected using an electrochemiluminescence (ECL) reagent (Thermo Scientific, IL, USA). The samples were subjected to western blot analyses as described previously [
25].
Total quantitative real-time PCR analysis
RNAs were isolated from cells using Triozol reagent (sigma) according to the manufacturer’s instructions. The quantity and quality of the extracted total RNA were assessed by using a Nanodrop 1000 spectrophotometer (Thermo Scientific). One microgram of total RNA was reverse-transcribed into complementary DNA with HiScript III 1st Strand cDNA Synthesis Kit with gDNA Wiper (Vazyme;R312-01). Quantitative PCR was performed with SYBR qPCR Master Mix (Vazyme; MQ101-01) and quantified by the StepOne Real-Time PCR System (Applied Biosystems). The signals were detected and analyzed on CFX Connect System (Bio-rad, USA). GAPDH was used as an internal control. The amplification parameters were set at 95 ℃for 30 s, 60 ℃ for 30 s, and 95 ℃ for 10 s (40 cycles total). Gene-specific primers used in the study were:
YAP: TGTCCCAGATGAACGTCACAGC (forward), TGGTGGCTGTTTCACTGGAGCA(reverse);
GLUT1: TTGCAGGCTTCTCCAACTGGAC(forward), CAGAACCAGGAGCACAGTGAAG(reverse); GAPDH:GTCTCCTCTGACTTCAACAGCG(forward), ACCACCCTGTTGCTGTAGCCAA(reverse).
Transmission electron microscopy (TEM)
Curcumin- and WZ35-induced changes in the cellular structure were visualized via TEM, with DMSO being used as a control. The treated cells were pre-fixed overnight in primary fixative (2.5% glutaraldehyde and 1 mM CaCl2 in 0.15 M cacodylate buffer), followed by a 2 h post-fix in 1% osmium tetroxide. Subsequently, specimens were dehydrated in an ascending ethanol gradient (50%, 70%, 90%, 95% and 100% three times; each step 5 min) and in isoamyl acetate 15 min. Ultrathin pellet sections were then stained using 2% aqueous uranyl acetate and lead citrate, after which a TEM instrument (Wenzhou Medical University, H-7500, HITACHI, Japan) was used to image the cells with 26,500 magnification.
Oxidative phosphorylation and glycolysis measurements
A Seahorse XF96 Extracellular Flux Analyzer (Agilent Technologies, CA, USA) was used for oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) measurements. 2 × 104 cells add to machine-specific plates. Drug doses were used to treat cells for 6 h. Following probe calibration, OCR was measured via sequentially injecting oligomycin (ATP synthase inhibitor; 1 µM), FCCP (uncoupler; 0.5 µM), rotenone (complex I inhibitor; 1 µM), and antimycin A (complex III inhibitor; 2 µM). ECAR was measured using the cells treated in the same manner via injection of glucose (10 mM), oligomycin (1 µM), or 2-DG (100 mM).
Flow cytometry analysis for ROS determination
ROS production was quantified by staining the cells for 30 min with 10 μM 2,7-dichlorofluo-rescein diacetate (DCFH-DA) in DMEM at 37 °C. The cells were then treated for 2 h with corresponding compounds (10 μg/mL), washed twice with DMEM, and DCFH-DA fluorescence was quantified by BD Accuri TM C6 flow cytometer (BD, Franklin Lakes, NJ).
Detection of glucose in the supernatant
Cells were plated in 3 dishes (60 mm) with DMSO (10 μL/mL), WZ35 (10 μg/mL) and blank. After a 18 h-drug-treatment, the supernatant was collected. According to Beckman Kurt biochemical analysis system, glucose determination kit (Beckman Coulter, CA, USA) was used to detect the glucose content in the culture medium supernatant. In the presence of adenosine triphosphate (ATP) and magnesium ions, the glucose was phosphorylated by hexokinase (HK) to produce glucose-6-phosphate and adenosine diphosphate (ADP). The increase of absorbance at 340 nm was proportional to the glucose concentration in the sample.
A CCK-8 kit was used to measure the cellular proliferation. HCCLM3 cells were plated in 96-well plates (8 × 103/well) overnight, medium was changed to sugar-free medium the next day, after which the cells were left untreated or treated with Glucose (1 mM), Glucose (25 mM), 2-DG (1 mM), WZ35 (10 μg/mL). After an 18 h-drug treatment, the CCK-8 kit was used to measure the viability, with absorbance at 450 nm being quantified via microplate reader (Spectramax m5, Molecular Devices).
TCA: Targeted metabolite analysis was performed on a Xevo G2-XS QT of mass spectrometry coupled with an ACQUITY UPLC (Ultra Performance Liquid Chromatography) system and data analysis was done with Progenesis QI (all from Waters, Milford, MA, USA). The metabolites in a homogenate of 1 × 106 cells were extracted using chloroform, methanol, and water at a ratio of 8:4:3 and resuspended in 1% acetonitrile. For UPLC, the samples were injected on an HSS T3 column (100 × 2.1 mm, 1.8 μm) using an 8-min gradient containing flow phase A (0.1%formic acid–water) and flow phase B (0.1% formic acid-acetonitrile) at a flow rate of 0.5 ml/min. For the negative ion mode, the capillary energy and sample cone were set as 2000 V and 20 V, respectively. Scan time was set at 0.1 s intervals for 60 s.
Other metabolomics: A. 95% water: 5% acetonitrile + 10 mM ammonium acetate + NH4OH (PH = 10); B. 95% acetonitrile: 5% water + 10 mM ammonium acetate + NH4OH (PH = 10). Waters Acquity UPLC BEH Amide 2.1 × 100 mm, 1.7 μm. Time, flow velocity (mL/min), A1%, B1% were arranged in the following order: initial, 0.4, 1, 99; 0.1, 0.4, 1, 99; 6, 0.4, 70, 30; 6.5, 0.4, 1, 99; 10, 0.4, 1, 99.
Tumor transplantation
Female BALB/c nude mice (6–8 weeks old; ~ 20 g) from Wenzhou Medical University Laboratory Animal Center were housed under SPF conditions. All procedures performed in studies involving humans and animals were in accordance with the ethical standards of the ethic committee of Wenzhou Medical University and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Animals were subcutaneously injected with a 100 μL volume containing 5 × 106 HCCLM3 cells in the right flank. When tumors grew to 100 mm3, the mice were randomized into 4 groups (n = 6/group) that were intraperitoneally administered saline, vehicle, curcumin (25 mg/kg), or WZ35 (25 mg/kg) daily for 17 consecutive days. Body weight and tumor volumes were monitored every other day, with the latter being calculated as follows: tumor volume = length × width × height/2. After 17 days, Intraperitoneal injection of 300 mg/kg sodium pentobarbital was used to euthanize mice. Upon examination, all mice lost heartbeat, breathing and righting reflex within two minutes and were therefore judged dead. The tumor tissues were collected to make paraffin sections for HE staining. Our project was conducted under guidelines approved by the Experimental Animal Ethics Committee of Wenzhou Medical University (ID number: wydw2019-0446).
In order to reflect the welfare and "3R" principles in animal experiments, and to "optimize" the animal experiment strategy, we set up "humane endpoints" to help animals reduce end-of-life pain and stress.Carry out detailed inspections at least twice a week, and increase the number of observations after the emergence of toxic manifestations:
General observations: rapid weight loss of 10–20%, loss of appetite or poor appetite, neurodepression with hypothermia without anesthesia, clinical symptoms of organ dysfunction and ineffective treatment, persistent effects of self-harm eating and drinking;Specific indicators: When the tumor growth volume exceeds 10% of the animal's body weight, the average diameter exceeds 15 mm, or the tumor surface ulcers or even causes infection or necrosis.In the event of any of the above symptoms, the experimenter will consider terminating the experiment immediately.
Tissue microarrays (TMAs) and IHC staining
Liver cancer TMAs composed of 110 FFPE tissue Sects. (4 μm thick) were prepared the same way as previously described by Guttà C et al. [
31] TMA IHC staining was conducted based on a standard approach. Briefly, the sections were deparaffinized using xylene, rehydrated with an ethanol gradient, treated to quench peroxidase activity, blocked with 5% normal goat serum, and incubated with anti-YAP/GLUT1 (1:200) overnight at 4 °C. As a negative control, the antibody was omitted. The slides were then probed with biotin-labeled goat anti-rabbit IgG, treated with a streptavidin peroxidase solution (SABC kit, Boster, Wuhan, China), and then 3,3-diaminobenzidine (Boster, Wuhan, China) in PBS with 0.05% H2O2 was used to treat the samples for 5 min at the room temperature for color development, after which the samples were counterstained using hematoxylin.
IHC staining assessment
Two pathologists blinded to the samples evaluated the clinicopathological information independently and scored IHC images of TMA samples. We utilized the Image-Pro Plus 6.0 (IPP) (Media Cybernetics, MD, USA) to calculate the integrated optical density (IOD) for the stained images, with this value corresponding to total staining per sample area [
32]. Entire TMAs were scanned in order to quantify protein levels in the TMA levels. IHC staining was evaluated based on immunoreactive score (IRS) values as described in the prior studies, with these scores reflecting both staining intensity and the percentage of the positive cells [
25]. The percent positivity was stained as follows: 1 (≤ 10%), 2 (10–50%), 3 (50–80%), or 4 (≥ 80%). The staining intensity was scored as: 0 (negative), 1 (weak), 2 (moderate), or 3 (strong). These two scores were then multiplied together to yield the IRS value (0 – 12), with these values being deemed either low (≤ 6) or high (> 6).
Statistical analysis
SPSS 19.0 (SPSS Inc., IL, USA) was utilized for statistical analysis. The data has been represented as the means ± SD from three independent experiments, and was compared via unpaired Student’s t-tests. The multi-group data were compared via Kruskal–Wallis test. Spearman's rank correlation coefficient test was applied to correlation analysis. Log-rank test was used for survival analysis. P < 0.05 was set as the significance threshold.
Discussion
Liver cancer is the second deadliest and fifth most prevalent cancer type globally in 2020 [
1]. However, the onset of liver cancer is insidious, and once discovered, it is mostly diagnosed an advanced stage. Therefore, identification of efficient treatment and treatment targets for liver cancer has become an urgent problem [
34].
WZ35, developed by our team, is an analog of curcumin that can suppress the growth of variety of tumors by targeting YAP [
23‐
26]. One of our previous study [
24] found that WZ35 could inhibit glycolysis. We further discovered that WZ35 blocked glucose absorption and investigated the metabolic changes in hepatocellular carcinoma cells after that through metabolomics. According to the desperate glucose demanding of cancer cells, some scholars suggested that intermittent fasting might diminish the progression of tumors [
35]. Clinical data showed that fasting can prevent DNA injury and immune cells damage induced by chemotherapy [
36]. Combining fasting with other therapies can prevent drug resistance and reduce side effects [
37]. However, the lack of nutrition caused by fasting makes the overall anti-cancer effect unsatisfactory. For example, the reduction of glutamine due to glucose deficiency can alleviate immune infiltration in the tumor microenvironment [
38]. Fasting might induce more diseases such as anemia, neurocognitive deficits [
39], etc. In this study, we demonstrated that the glucose blocking ability of WZ35 is one of its main anti-cancer mechanisms (Fig.
6I). And that suggests, WZ35 has the same anti-cancer effect as intermittent fasting, and it also cleverly avoids serious side effects caused by the deficiency of other nutrition, which makes WZ35 a promising candidate drug for cancer therapy.
To further elucidate the underlying mechanism, we investigated the WZ35-induced inhibition of glucose uptake at the molecular level. Our study revealed that WZ35 can disrupt ROS homeostasis and downregulate the YAP signal in nucleus through reducing the total protein content and blocking its translocation from cytoplasm to nucleus. Although the role of YAP in organ regeneration [
40,
41] and atherosclerosis [
42] has been well-studied, how YAP takes part in glucose mechanism remains unknown. In this study, we demonstrated that WZ35 affected the expression of GLUT1 to impair glycolysis via regulating YAP expression in hepatocellular carcinoma cells. GLUT1, as the primary glucose transporter, is considered to be the most highly conserved and widely found glucose transporter in different cancers [
8]. A recent study showed that endogenous TEAD plays an essential role in mediating GLUT1 expression and upregulating glycolysis in the progress of cardiac hypertrophy [
43]. Based on our results above, we reasonably believed that the YAP-TEAD complex formed on the distal promoter or the enhancer of the GLUT1 gene may involve in the interaction mechanism between YAP and GLUT1. H3K4me3 is positively associated with gene expression and is regarded as co-factors of translation modifications which always gathers around transcription start sites [
44]. By analyzing JASPAR database, we predicted five potential TEAD-binding sites in the promoter region of GLUT1. Four of them were found to have increased level of histone modifications associated with H3K4me3. It Increased credibility of the hypothesis that in hepatocellular carcinoma cells, YAP may mediate glycolysis through YAP-TEAD-GLUT1 pathway. Nevertheless, this hypothesis requires more direct and convincing evidences in future investigations.
To further explore potential clinical applications of the experimental data, we assessed the relationship of YAP and GLUT1 expression levels in hepatocellular carcinoma tissue with clinicopathologic features of HCC patients. Multi-variate Cox proportional hazards analysis testified that YAP and GLUT1 has important reference significance for predicting the stages of disease progression in liver cancer patients. It suggested that YAP and GLUT1 may be promising biomarkers in HCC for diagnosis, treatment and prognosis.
We next explored the role glucose uptake inhibition taken in cellular metabolic network. Increased glucose uptake is seen as the main characteristic of tumor cells. Glycolysis and oxidative phosphorylation take on critical roles in glucose metabolism [
45].
This study revealed that WZ35-induced relative glucose shortage restrained glycolysis and oxidative phosphorylation. And our metabolomics analysis showed that WZ35 can inhibit purine metabolism. Many intermediates in glycolysis can be precursors of different biosynthetic procession. For example, 5-phosphate ribose, the structural component of nucleotides, is partially oxidized from 6-phosphate glucose (PPP) [
46]. Current studies suggested that the level of oxidative phosphorylation is closely related to proliferation ability [
47,
48]. Generation of the nucleotide bases in purine nucleotide metabolism can promote the proliferation of glutamine-deficient cells [
49,
50]. Thus, we speculated that WZ35 may block glycose uptake to inhibit the progress of both glycolysis and oxidative phosphorylation, thereby decreases the proliferation activity of HCCLM3.
In conclusion, we demonstrated that, compared with curcumin, WZ35 reveals superior antitumor activity. It mediates ROS/YAP/GLUT1 loop to inhibit glucose uptake and oxidative phosphorylation, which ultimately decreases the proliferation activity of liver cancer cells. These findings may deepen our understanding regarding the ROS/YAP/GLUT1 loop in HCC metabolic process. Besides, YAP-GLUT1 has reference significance in predicting the stages of progression in HCC. It is promising to become novel biomarkers for the diagnosis and treatment of liver cancer.
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