Ferroptosis-inducing compounds synergize with docetaxel to overcome chemoresistance in docetaxel-resistant non-small cell lung cancer cells.

Development of resistance to therapy-induced cell death is a major hurdle in the effective treatment of advanced solid tumors. Erastin and RSL3 were originally found to induce synthetic lethality by induction of a novel form of cell death termed ferroptosis. Emerging evidence suggests that ferroptosis inducers enhance chemosensitivity of classic therapeutic agents by triggering ferroptotic cell death. In this study we evaluated the effects of erastin and RSL3 on the resistance of docetaxel, doxorubicin, and cisplatin, and revealed a mechanism whereby these ferroptosis inducers augment docetaxel efficacy in non-small cell lung cancer by regulating redox signaling to promote ferroptosis. Transcriptome analysis revealed that combination treatment modulated not only p53 signaling pathway but also immune responses and several signaling pathways including MAPK, NF-κB and PI3K/Akt. Considering that glutathione peroxidase 4 (GPX4) serves as the main effector to protect cells from ferroptosis, this study identified three novel non-covalent GPX4 inhibitors with the aid of pharmacophore-based virtual screening. The new ferroptosis-inducing compounds synergized with docetaxel to increase the cytotoxicity by promoting ferroptotic cell death in docetaxel-resistant A549/DTX cells. Collectively, the induction of ferroptosis contributed to docetaxel-induced cytotoxic effects and overcame drug resistance in A549/DTX cells. Ferroptosis has a great potential to become a new approach to attenuate resistance to some classic therapeutic drugs in cancer patients.

TMEM189 as a target gene of MiR-499a-5p regulates breast cancer progression through the ferroptosis pathway.

MicroRNA (miR)-499a-5p has been reported to regulate the progression of various tumours. However, the role of miR-499a-5p in breast cancer is unclear. The purpose of this study was to investigate the role and mechanism of miR-499a-5p in breast cancer. The growth effect of miR-499a-5p on breast cancer cells was investigated by the CCK-8 assay, wound healing assay and Transwell invasion assay. The luciferase activity assay was used to verify the downstream targets of miR-499a-5p. The levels of GSH, MDA, and ROS were detected by kits. Quantitative real-time PCR and Western blot were used to determine the expression levels of TMEM189, COX-2, GPX4, and other related genes in cells. miR-499a-5p was down-regulated in MDA-MB-231 cells and was shown to reduced the viability, migration and invasion of MDA-MB-231 cells. Further studies revealed that TMEM189 is a target of miR-499a-5p. miR-499a-5p inhibited breast cancer cell growth by downregulating TMEM189. Furthermore, the down-regulation of TMEM189 promotes ferroptosis in breast cancer cells. The low expression of TMEM189 inhibited the development of breast cancer through the ferroptosis pathway. We have demonstrated for the first time that miR-499a-5p inhibits breast cancer progression by targeting the TMEM189-mediated ferroptosis pathway.

Wip1 contributes to the adaptation of HepG2 human liver cancer cells to stress hormone-induced DNA damage.

Numerous studies have shown that the release of stress hormones resulting from repeated exposure to chronic psychological stress increases DNA damage and promotes tumorigenesis. However, the mechanisms that enable cancerous cells adapt to stress hormone-induced DNA damage and survive remain unclear. The present study aimed to investigate the impact of stress hormones on the survival of liver cancer cells and the underlying mechanism. HepG2 human liver cancer cells were treated with dexamethasone (DEX), epinephrine (EPI) and norepinephrine (NE) and subjected to the testing of DNA damage, cell survival and cell apoptosis by alkaline comet assay, CCK-8 viability assay and flow cytometry, respectively. The protein expression levels of DNA damage response factors were determined by western blotting analysis. The results revealed that treatment of HepG2 cells with DEX, EPI and NE induced DNA damage without affecting cell survival or inducing apoptosis. The protein levels of wild-type p53-induced phosphatase 1 (Wip1), a type 2C family serine/threonine phosphatase, were increased, and the dephosphorylation of DNA damage response factors, including phosphorylated (p-)ataxia-telangiectasia mutated and p-checkpoint kinase 2, occurred following treatment with DEX, EPI and NE. In addition, a cycloheximide chase assay was performed to explore the protein stability under treatment with stress hormones. Compared with vehicle-treated cells, Wip1 exhibited increased protein stability in stress hormone-treated HepG2 cells. Eventually, the depletion of Wip1 using small interfering RNA verified the role of Wip1 in the modulation of stress hormone-induced DNA damage. These findings suggest that cancerous cells likely adapt to stress hormone-induced DNA damage via Wip1 upregulation. The present study provides an insight into the underlying mechanism that links chronic psychological stress with tumor growth and progression.

Construction and validation of an angiogenesis-related scoring model to predict prognosis, tumor immune microenvironment and therapeutic response in hepatocellular carcinoma.

Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world with high morbidity and mortality. Identifying an effective marker for predicting the prognosis and therapeutic response is extremely meaningful. Angiogenesis-related genes (ARGs) play important roles in the tumor progression and immune-suppressive microenvironment formation. Methods: The differential expressed ARGs associated with the prognosis of HCC were identified in the TCGA dataset. Univariate Cox and least absolute shrinkage selection operator (LASSO) regression were applied to construct a ARGs Scoring model. The prognostic value of the ARGs Scoring model was assessed by Cox regression, Kaplan-Meier (KM) and ROC curve analyses. Then the model was further validated in an external dataset, ICGC dataset. The patients were split into two groups based on the ARGs Score and the clinical features were compared. TIMER, CIBERSORT and xCell algorithms were utilized to analyze the correlation between the ARGs Score and tumor immune microenvironment (TIME). Furthermore, we analyzed the efficacy of the model in predicting the therapeutic response for immunotherapy, targeted therapy and TACE treatment in different cohorts. Results: A total of 97 differential expressed ARGs were identified relating to the prognosis of HCC patients from the TCGA dataset. Then the ARGs Scoring model based on a 9-gene signature was constructed using the Cox and LASSO regression analyses. Higher ARGs Score had a poor clinical outcome and was considered to be an independent prognostic predictor for HCC in the multivariate Cox analysis. The ARGs Score was related to the enrichment of various immune cells, such as CD4+ T cells, Treg, macrophage, neutrophil and dendritic cells, exhibiting a more immunosuppressive phenotype. Higher ARGs Score was correlated with higher expression of immune checkpoint genes and poor response to immunotherapy. Furthermore, higher ARGs Score indicated poor therapeutic response in the sorafenib and TACE treatment cohorts, individually. Conclusions: The ARGs Scoring model exhibited robust predictive value for the prognosis and TIME for HCC patients. Higher ARGs Score indicated poor therapeutic response of the immunotherapy, sorafenib and TACE treatment. The ARGs Scoring model could be used as a biomarker to help physicians to develop more individualized treatment for HCC patients.

Comprehensive Analyses of MELK-Associated ceRNA Networks Reveal a Potential Biomarker for Predicting Poor Prognosis and Immunotherapy Efficacy in Hepatocellular Carcinoma.

Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world with high morbidity and mortality. Identifying specific molecular markers that can predict HCC prognosis is extremely important. MELK has been reported to play key roles in several types of human cancers and predict poor prognosis. This study was aimed to explore the impact of MELK on HCC. Methods: A pan-cancer analysis of MELK was conducted by The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) data. The prognosis of MELK in various cancers was analyzed in GEPIA. Then, a ceRNA network of MELK was constructed based on the comprehensive consideration of the expression analysis, the correlation analysis, and the survival analysis by R software. The correlation of MELK and immune cell infiltration was analyzed by TIMER and CIBERSORT. Then, the overall survival of differentially expressed immune cells was conducted. The correlation of MELK and immune checkpoints expression was analyzed by GEPIA. Results: MELK was overexpressed in 14 types of human cancers, and its expression was significantly higher than that in both unmatched and paired normal samples in HCC. Higher MELK expression was correlated with poorer survival and advanced clinical stage, topography (T) stage, and histological grade. The univariate and multivariate Cox regression analyses showed that MELK was an independent risk factor for poor prognosis in HCC. Then, we constructed a ceRNA network consisting of MELK, miR-101-3p, and two lncRNAs (SNHG1 and SNHG6) after evaluating the expression and impact on prognosis in HCC of these RNAs. TIMER and CIBERSORT databases indicated that MELK was correlated with various immune cells including B cells, CD8+ T cells, CD4+ T cells, macrophage, neutrophil, and dendritic cells in HCC. Of them, B cells, CD4+ T cells, macrophage, and neutrophil were related to the prognosis of HCC. In addition, MELK was significantly positively correlated with the immune checkpoint genes. Conclusions: MELK may be a novel potential biomarker for predicting prognosis and immunotherapy efficacy in patients with HCC. Our study may provide new molecular and therapeutic strategies for the treatment of HCC patients.

DTX-P7, a peptide-drug conjugate, is highly effective for non-small cell lung cancer.

Despite tremendous success of molecular targeted therapy together with immunotherapy, only a small subset of patients can benefit from them. Chemotherapy remains the mainstay treatment for most of tumors including non-small cell lung cancer (NSCLC); however, non-selective adverse effects on healthy tissues and secondary resistance are the main obstacles. Meanwhile, the quiescent or dormant cancer stem-like cells (CSLCs) are resistant to antimitotic chemoradiotherapy. Complete remission can only be realized when both proliferative cancer cells and quiescent cancer stem cells are targeted. In the present research, we constructed a cooperatively combating conjugate (DTX-P7) composed of docetaxel (DTX) and a heptapeptide (P7), which specifically binds to cell surface Hsp90, and assessed the anti-tumor effects of DTX-P7 on non-small cell lung cancer. DTX-P7 preferentially suppressed tumor growth compared with DTX in vivo with a favorable distribution to tumor tissues and long circulation half-life. Furthermore, we revealed a distinctive mechanism whereby DTX-P7 induced unfolded protein response and eventually promoted apoptosis. More importantly, we found that DTX-P7 promoted cell cycle reentry of slow-proliferating CSLCs and subsequently killed them, exhibiting a "proliferate to kill" pattern. Collecitvely, by force of active targeting delivery of DTX via membrane-bound Hsp90, DTX-P7 induces unfolded protein response and subsequent apoptosis by degrading Hsp90, meanwhile awakens and kills the dormant cancer stem cells. Thus, DTX-P7 deserves further development as a promising anticancer therapeutic for treatment of various membrane-harboring Hsp90 cancer types.

Efficacy of Combined Management with Nonsteroidal Anti-inflammatory Drugs for Prevention of Pancreatitis After Endoscopic Retrograde Cholangiography: a Bayesian Network Meta-analysis.

OBJECTIVES: To systematically evaluate the clinical efficacy of rectal nonsteroidal anti-inflammatory drugs (NSAIDs) alone or in combination with other agents for preventing pancreatitis after endoscopic retrograde cholangiopanography. METHODS: We carried out a literature search of random controlled trials (RCTs) on preventing post-operative pancreatitis by administration of the anti-inflammatory drugs, indomethacin and diclofenac, following endoscopic retrograde cholangiopancreatography (ERCP). The databases searched for relevant publications up to July 7, 2021, included PubMed, Cochrane Library, and Embase. We screened the literature according to inclusion criteria and analyzed the extracted data. The overall population and high-risk patient groups were analyzed, with the main outcome being the incidence of PEP. RESULTS: The search identified 32 RCTs that included 15019 patients with post-ERCP pancreatitis and 9 different interventions. The results of the overall population network meta-analysis showed that NSAIDs alone, high-dose NSAIDs, and a combination of NSAIDs significantly reduced the incidence of PEP compared with placebo. However, compared with placebo, there was no statistically significant difference between the two interventions (NSAIDs + standard hydration and high-dose NSAIDs). In addition, NSAIDs + sublingual nitrates were associated with a lower incidence of PEP compared to that observed with NSAIDs alone. Probability ranking results showed that NSAIDs + sublingual nitrate had the best effect, followed by NSAIDs + standard hydration, NSAIDs + melatonin, NSAIDs + aggressive hydration, NSAIDs + somatostatin, NSAIDs alone, NSAIDs + epinephrine, high-dose NSAIDs, and placebo. In the high-risk subgroup, the results of the network meta-analysis showed that NSAIDs alone, high-dose NSAIDs, and a combination of NSAIDs showed no statistically significant difference in their ability to reduce the incidence of PEP compared with placebo. Probability ranking results showed that NSAIDs + hydration had the best effect, followed by NSAIDs + sublingual nitroglycerin and NSAIDs + aggressive hydration. CONCLUSION: Of the nine interventions, NSAIDs + sublingual nitrates had considerably better efficacy than the other drugs for reducing the incidence of PEP in the overall population. In high-risk patients, NSAIDs + standard hydration may be the best preventive treatment; however, more randomized, controlled trials are needed to validate our results. TRIAL REGISTRATION: Name of the registry: PROSPERO-International prospective register of systematic reviews. Unique identifying number or registration ID: CRD42021282205.

The Prognostic Significance of C-Reactive Protein to Albumin Ratio in Patients With Severe Fever With Thrombocytopenia Syndrome.

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with the high case-fatality rate, lacking effective therapies and vaccines. Inflammation-based indexes have been widely used to predict the prognosis of patients with cancers and some inflammatory diseases. In our study, we aim to explore the predictive value of the inflammation-based indexes in SFTS patients. Methods: We retrospectively analyzed 82 patients diagnosed with SFTS. The inflammation-based indexes, including neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), aggregate index of systemic inflammation (AISI) and C-reactive protein to albumin ratio (CAR), were compared between the survival and death patients. Receiver operating characteristic (ROC) curves were used to compare the predictive ability of MLR, AISI, and CAR. The survival analysis was based on the Kaplan-Meier (KM) method. Multivariate logistic regression analysis was used to analyze the independent risk factors of poor prognosis in patients with SFTS. Results: The CAR is higher in the death group while MLR and AISI were higher in the survival group. The ROC curve analysis indicated CAR exhibited more predictive value than the other indexes and the optimal cut-off value of CAR was equal to or greater than 0.14. KM survival curve showed that higher CAR was significantly correlated to the lower overall survival in SFTS patients. Multivariate logistic regression analysis indicated that CAR was an independent risk factor for poor prognosis in patients with SFTS. Conclusion: The CAR is an independent risk factor for death in patients with SFTS and could predict the poor prognosis of SFTS patients. It could be used as a biomarker to help physicians to monitor and treat patients more aggressively to improve clinical prognosis.

Green-light-responsive metal-organic frameworks for colorectal cancer treatment.

Herein, the synthetic methods for preparation of a novel light-responsive metal-organic framework (MOF) UiO-AZB-F are outlined. Upon irradiation with green light, the framework demonstrates controlled release of chemotherapeutic drug cargo with simultaneous breakdown into low toxicity small molecule components.

Hyaluronan-mediated motility receptor antisense RNA 1 promotes hepatitis B virus-related hepatocellular carcinoma progression by regulating miR-627-3p/High Mobility Group AT-hook 2 axis.

Hepatocellular carcinoma (HCC) is a common malignancy in the world, with high mortality and poor prognosis. Hepatitis B virus (HBV) is one of the key factors implicated in the occurrence of HCC. Increasing evidence suggests that miRNAs play important roles in the development and metastasis of HBV-associated HCC (HBV-HCC). Here, we performed CCK8 (Cell count kit-8), EdU (5-ethynyl-2'-deoxyuridine) incorporation assay, wound-healing assay, transwell assay to study the changes in the cellular phenotype. Luciferase reporter assay, RNA pull-down experiment, RT-qPCR and western blotting were employed to study molecular mechanism. In addition, we also constructed a mouse HCC xenograft model to verify the functional role of HMMR-AS1/miR-627-3p/HMGA2 signal axis in vivo. Our study demonstrated that HMMR-AS1 was highly expressed in HCC tissues and cell lines, suggesting its implication in the progression of HCC. In addition, in vitro experiments showed that high HMMR-AS1 expression facilitated the migration, invasion, and proliferation of HCC cells. We further revealed that HMMR-AS1 promoted the malignant phenotype of HCC cells by regulating miR-627-3p/HMGA2 axis. Together, our data suggest that HMMR-AS1 regulates HBV-HCC progression via miR-627-3p/HMGA2 axis.

Effectiveness and safety of ultrasound-guided percutaneous microwave ablation for hepatic alveolar echinococcosis.

BACKGROUND: Microwave ablation (MWA) is a popular therapy for liver malignant tumor in recent years. Few studies have been conducted on its use in the treatment of hepatic alveolar echinococcosis (HAE). The study aims to evaluate the efficacy and safety of MWA in the treatment of HAE. METHODS: This study analyzed the data of 45 patients (mean age, 38 ± 2 years; 24 males) diagnosed with HAE and underwent MWA treatment between June 2014 to December 2019. The patients after MWA were examined by CT or MRI [follow-up: 32 months (IQR 23-48.5)] to determine whether the lesions were relapsed and to evaluate the therapeutic effect of MWA. The safety of MWA was evaluated by monitoring postoperative complications. Clinical data, such as patient demographics, imaging features of the lesions, relevant findings of laboratory tests before and after ablation, and information related to ablation, were collected and analyzed. Paired-sample t tests and paired-sample Wilcoxon signed-rank tests were used to compare relevant laboratory indicators before and after MWA. RESULTS: MWA was applied to 57 HAE lesions in 45 patients. The median size of lesions was 3.42 cm (IQR2.85-4.41). The rate of complete ablation was 100% (57/57). The median follow-up time was 32 months (IQR 23-48.5). The recurrence rate was 13% (6/45), and the median time of recurrence was 22 months. The rate of minor complications was 11.1% (5/45), and there were no major complications and deaths. Compared to preoperative, ALB, RBC, HBG, and PLT were decreased (p < 0.001); ALT, TB, DB, and WBC were increased (p < 0.001); and no statistically difference in PT, APTT, and INR (p > 0.05). CONCLUSIONS: MWA might be a safe and effective way to cure HAE. Meanwhile, it provides a new option and a new way of thinking about treatment for patients with HAE.

Analysis of the efficacy of microwave ablation in the treatment of early hepatic alveolar echinococcosis: A propensity score matching based study.

BACKGROUND: To explore the efficacy of microwave ablation (MWA) in the treatment of hepatic alveolar echinococcosis (HAE) with a diameter of ≤5 cm. METHOD: From June 2014 to January 2020, patients diagnosed with HAE were retrospectively analyzed. After balancing the confounding factors by propensity score matching (PSM) , the patients were divided into MWA group (n = 20) and radical operation group (n = 20) by 1:1 matching. The safety and effectiveness of MWA were assessed by comparing the differences between the two groups in terms of postoperative general laboratory indices, grading of postoperative complications, length of postoperative hospitalization, the outcome of treatment, and disease recurrence. RESULT: After PSM, all confounders were not statistically different (P>0.05) . Compared with the radical surgery group, patients in the MWA group had lower postoperative ALT and WBC elevations (P<0.001) , shorter postoperative hospital stay (P<0.001) ) , lower hospital costs (P<0.001) . The effective rate of the two groups was 100%. There was no statistical difference in the incidence of postoperative complications and recurrence rate (P>0.05). CONCLUSION: MWA is a safe and effective means of treating HAE ≤ 5 cm in diameter.

Role of Spin-Orbit Coupling in Long Range Energy Transfer in Metal-Organic Frameworks.

Metal-organic frameworks (MOFs) are emerging as a promising platform for solar energy conversion applications. Their potential utilization as efficient chromophores in artificial photosynthesis is closely related to the understanding of light-harvesting and energy transfer processes that occur within these molecular scaffolds. Herein, we present the photophysical investigation of Ru(II), Ir(III), and Os(II) polypyridyl complexes incorporated into the backbone of UiO-67. In this work, we systematically study the effect of spin-orbit coupling on dipole-dipole energy transfer in MOFs using steady-state and time-resolved spectroscopic techniques. The results of our work indicate successful triplet-to-singlet energy transfer and a sizable increase in the transfer kinetics and critical distance, as direct consequences of strong spin-orbit couplings. Remarkably, the reported R0 value for OsDCBPY (R0 = 88 ± 10 Å) represents one of the largest Förster distances observed in an MOF. Collectively, this work contributes to the general knowledge of energy transfer in materials and provides groundwork for efficient utilization in artificial photosynthetic assemblies.

Nickel(II)-modified covalent-organic framework film for electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF).

Electrochemical oxidation of 5-hydroxymethylfurfural (HMF) is a promising synthetic route for 2,5-furandicarboxylic acid (FDCA) production. Here, we prepared a nickel(ii)-modified covalent-organic framework (COF) film TpBpy-Ni@FTO for HMF electrooxidation. With a high conversion of HMF (96%), TpBpy-Ni@FTO afforded a 58% FDCA yield. This work underlines the great potential of COF-based materials in electrocatalysis.

Molecular-Level Control over Plasmonic Properties in Silver Nanoparticle/Self-Assembling Peptide Hybrids.

The plasmonic properties of silver nanoparticle (AgNP) arrays are directly controlled by AgNP size, shape, and spatial arrangement. Reported here is a strategy to prepare chiral AgNP arrays templated by two constitutionally isomeric aromatic peptide amphiphiles (APAs), KSC'EKS and C'EKSKS (KS = S-aroylthiooxime-modified lysine, C' = citrulline, and E = glutamic acid). In phosphate buffer, both APAs initially self-assembled into nanoribbons with a similar geometry. However, in the presence of silver ions and poly(sodium 4-styrenesulfonate) (PSSS), one of the nanoribbons (KSC'EKS) turned into nanohelices with a regular twisting pitch, while the other (C'EKSKS) remained as nanoribbons. Both were used as templates for synthesis of arrays of ∼8 nm AgNPs to understand how small changes in molecular structure affect the plasmonic properties of these chiral AgNP/APA hybrids. Both hybrids showed improved colloidal stability compared to pure AgNPs, and both showed enhanced sensitivity as surface-enhanced Raman spectroscopy (SERS) substrates for model analytes, with nanohelices showing better SERS performance compared to their nanoribbon counterparts and pure AgNPs.

Mechanism of UVA Degradation of Synthetic Eumelanin.

Eumelanin is a ubiquitous natural pigment that has a broad absorption across ultraviolet (UV, 100-400 nm) and visible wavelengths (400-700 nm) and can protect against radiation. Synthetic eumelanin with properties similar to natural eumelanin has been made using dopamine or dihydroxyindole. Here, we use solid-state nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy to elucidate the chemical structure of synthetic eumelanins (made from dopamine and l-3,4-dihydroxyphenylalanine precursors) and investigate how their structures change after intensive UVA (315-400 nm) exposure. We first confirm that polydopamine has indole units. Upon UV exposure, the pyrrole ring in this indole unit remains intact, and a fraction of the six-membered benzyl ring is broken and the indole potentially converted to furo[3,4-b]pyrrole. This change in the chemical structure is accompanied by a release of carbon dioxide. In addition, the sepia (natural) eumelanin used for comparison is more stable than the synthetic eumelanin. Understanding the UVA degradation mechanism of eumelanin will help reveal the role of eumelanin in skin cancer and in the design of more efficient UV stabilizers.

USP22 knockdown enhanced chemosensitivity of hepatocellular carcinoma cells to 5-Fu by up-regulation of Smad4 and suppression of Akt.

USP22, a member of the deubiquitinases (DUBs) family, is known to be a key subunit of the human Spt-Ada-Gcn5 acetyltransferase (hSAGA) transcriptional cofactor complex. Within hSAGA, USP22 removes ubiquitin from histone proteins, thus regulating the transcription and expression of downstream genes. USP22 plays important roles in many cancers; however, its effect and the mechanism underlying HCC chemoresistance remain unclear. In the present study, we found that USP22 was highly expressed in chemoresistant HCC tissues and cells and was correlated with the prognosis of HCC patients who received chemotherapy. Silencing USP22 in chemoresistant HCC Bel/Fu cells dramatically inhibited proliferation, migration, invasion and epithelial-mesenchymal transition in vitro; suppressed tumorigenic and metastatic capacities in vivo; and inhibited drug resistance-related proteins (MDR1, LRP, MRP1). Mechanistically, we found that USP22 knockdown exerts its function through down-regulating PI3K and activating Smad4, which inhibited phosphorylation of Akt. Silencing Smad4 blocked USP22 knockdown-induced Akt inhibition in Bel/Fu cells. Our results, for the first time, provide evidence that USP22 plays a critical role in the development of chemoresistant HCC cells and that high USP22 expression serves as a molecular marker for the prognosis of HCC patients who undergo chemotherapy.