scholarly journals Identification of PAFAH1B3 as Candidate Prognosis Marker and Potential Therapeutic Target for Hepatocellular Carcinoma

2021 ◽  
Vol 11 ◽  
Author(s):  
Weikang Xu ◽  
Xinyu Lu ◽  
Jing Liu ◽  
Qianhui Chen ◽  
Xuan Huang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle ◽  
Cell Lines ◽  
Critical Role ◽  
Disease Free Survival ◽  
The Cancer Genome Atlas ◽  
Transwell Assay ◽  
Mutational Status ◽  
Prognosis Marker ◽  
Hcc Cells

BackgroundHepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related deaths worldwide. PAFAH1B3 plays an important role on occurrence and development in a variety tumor. However, the function of PAFAH1B3 in HCC remains unclear.MethodsThe TIMER, ONCOMINE, Human Protein Atlas (HPA), GEPIA, The Cancer Genome Atlas (TCGA), HCCDB, UALCAN and LinkedOmics database were used to analyze the prognostic value, co-expression genes and regulator networks of PAFAH1B3 in HCC. siRNA transfections and inhibitor of PAFAH1B3 P11 were used to verify the anti-tumor effect on HCC cell lines. Gene expression was detected by qRT-PCR. The functions of PAFAH1B3 downregulation in HCC cell lines were investigated using cell cycle analysis, apoptosis detection, CCK8 assay and transwell assay. Western blot was used to evaluate the role of PAFAH1B3 on metabolic pathways in HCC cells.ResultsBased on the data from databases, the expression of PAFAH1B3 was remarkably increased in HCC patients. High expression of PAFAH1B3 was associated with poorer overall survival (OS) and disease-free survival (DFS). And PAFAH1B3 was notably linked to age, sex, grade, stage, race, and TP53 mutational status. Then, the functional network analysis showed PAFAH1B3 may be involved in HCC through cell cycle, cell metabolism, spliceosome, and RNA transport. Furthermore, the mRNA expression of PAFAH1B3 was also increased in HCC cell lines. Flow cytometry analysis showed that PAFAH1B3 manipulated apoptosis and cell cycle regulation. CCK8 assay showed that PAFAH1B3 silencing or pharmacologic inhibitor of PAFAH1B3 inhibited the proliferation of HepG2, Huh7 and MHCC-97H cells. Transwell assay results showed that PAFAH1B3 silencing also significantly impaired the invasion and migratory ability of HCC cells. In addition, PAFAH1B3 silencing significantly downregulated the expression of glycolysis and lipid synthesis signaling pathways.ConclusionOur findings suggested that PAFAH1B3 plays a critical role in progression of HCC. PAFAH1B3 as a prognosis marker and potential target for HCC has prospective clinical significance.

scholarly journals High Expression of ANXA2 Pseudogene ANXA2P2 Promotes an Aggressive Phenotype in Hepatocellular Carcinoma

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Qiu-shuang Wang ◽  
Liang-Liang Shi ◽  
Fei Sun ◽  
Yi-fan Zhang ◽  
Ren-Wang Chen ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Disease Free Survival ◽  
Annexin A2 ◽  
The Cancer Genome Atlas ◽  
High Expression ◽  
Migration And Invasion ◽  
Targeted Drugs ◽  
Noncancerous Tissue ◽  
Expression Levels ◽  
Hcc Cells

Objective. Accumulating evidence suggests that pseudogenes play potential roles in the regulation of their cognate wild-type genes, oncogenes, and tumor suppressor genes. ANXA2P2 (annexin A2 pseudogene 2) is one of three pseudogenes of annexin A2 that have recently been shown to be aberrantly transcribed in hepatocellular carcinoma (HCC) cells. However, its clinical meaning and biological function in HCC have remained unclear. Therefore, the present study was aimed at exploring the prognostic value of a high expression of ANXA2P2 in HCC tissue and at identifying whether it can affect the efficacy of targeted drugs (sorafenib, regorafenib, and lenvatinib). Methods. We obtained ANXA2P2 mRNA expression levels from The Cancer Genome Atlas (TCGA) RNA sequence database. The expression levels of ANXA2P2 in 49 pairs of intratumoral and peritumoral liver tissues were examined by RT-PCR. Wound healing and transwell assays were performed to confirm the tumor-promoting properties of ANXA2P2 in HCC cells. CCK8 assay was conducted to identify whether ANXA2P2 can affect the growth of HCC cells when administered with targeted drugs (sorafenib, regorafenib, and lenvatinib). Results. The expression of ANXA2P2 in HCC tissues was significantly higher than that in adjacent cancerous tissues from TCGA database and validation group. Additionally, patients with high ANXA2P2 expression in HCC tissue had a shorter overall survival, whereas no statistically significant correlation was found between ANXA2P2 expression and disease-free survival (p=0.08) as well as other clinical parameters, such as age, gender, histological grade, T classification, stage, albumin level, alpha-fetoprotein, and vascular invasion (p=0.7323, 0.8807, 0.5762, 0.8515, 0.7113, 0.242, 1.0000, and 0.7685, respectively). Furthermore, in vitro experiments showed that knockdown of ANXA2P2 inhibited migration and invasion of HCC cells but did not have an influence on the HCC cell proliferation when treated with targeted drugs (sorafenib, regorafenib, and lenvatinib). Conclusion. Our study confirmed elevated ANXA2P2 expression levels in HCC tissue compared with adjacent noncancerous tissue and a worse prognosis of patients with high ANXA2P2 levels in the HCC tissue. The newly found properties of promoting migration and invasion of ANXA2P2 in HCC help to explain this phenomenon. ANXA2P2 could be a novel and suitable predicative biomarker for the risk assessment of recurrence or metastasis of HCC patients but may not be effective to predict the efficacy of targeted drugs.

Upregulation of SGOL2 Predicts Poor Prognosis and Facilitates Hepatocellular Carcinoma Progression via Dysregulating the Cell Cycle by Directly Activating MAD2

2021 ◽  
Author(s):  
Qingqing Hu ◽  
Xiaochu Hu ◽  
Yalei Zhao ◽  
Lingjian Zhang ◽  
Ya Yang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle ◽  
The Cancer Genome Atlas ◽  
Loss Of Function ◽  
Protein Levels ◽  
Cancer Genome Atlas ◽  
Centromeric Protein ◽  
Hcc Cells

Abstract Background: Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Shugoshin-like protein 2 (SGOL2) is a centromeric protein that ensures the correct and orderly process of mitosis by protecting and maintaining centripetal adhesions during meiosis and mitosis. However, the role of SGOL2 in cancer is not well understood. Methods: The mRNA and protein levels of SGOL2 and survival analysis were conducted in The Cancer Genome Atlas (TCGA) and further validated in 2 independent cohorts. Differential genes correlated with SGOL2 and mitotic arrest deficient 2 like 1 (MAD2) were obtained using LinkedOmics. Subsequently, loss-of-function and rescue assays were carried out in vitro and in vivo to assess the functions of SGOL2 in hepatic tumorigenisis. Findings: We found that SGOL2 was significantly overexpressed in HCC and predicted unfavorable overall survival in HCC patients. Next, we identified 47 differentially expressed genes positively correlated with both SGOL2 and MAD2 to be mainly involved in the cell cycle. In addition, SGOL2 downregulation suppressed the migration, invasion, proliferation, stemness and EMT of HCC cells and inhibited tumorigenesis in vivo. Furthermore, SGOL2 promoted tumor proliferation by activating MAD2-induced cell cycle dysregulation, which could be reversed by the MAD2 inhibitor M2I-1. We also proved that SGOL2 activated MAD2 by directly binding with MAD2. Conclusions: The results of this study showed that SGOL2 acts as an oncogene in HCC cells by directly activating MAD2 and then dysregulating the cell cycle, thereby providing a potential target for HCC patients in the future.

scholarly journals Melatonin enhances the anti-tumor effect of sorafenib via AKT/p27-mediated cell cycle arrest in hepatocarcinoma cell lines

RSC Advances ◽  
2017 ◽  
Vol 7 (34) ◽  
pp. 21342-21351 ◽  
Author(s):  
Fei Long ◽  
Chengyong Dong ◽  
Keqiu Jiang ◽  
Yakun Xu ◽  
Xinming Chi ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Cell Lines ◽  
Cycle Arrest ◽  
Hepatocarcinoma Cell ◽  
Proposed Model ◽  
Hcc Cells

Proposed model elucidating the role of MT in regulating the proliferation of hepatocellular carcinoma (HCC) cells treated with sorafenib.

scholarly journals Inhibition of HIF1A-AS1 promoted starvation-induced hepatocellular carcinoma cells apoptosis by reducing HIF-1α/mTOR mediated autophagy

2020 ◽  
Author(s):  
Fenfen Hong ◽  
Yu Gao ◽  
Yang Li ◽  
Linfeng Zheng ◽  
Feng Xu ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Lines ◽  
Disease Free Survival ◽  
Cell Counting ◽  
Normal Tissues ◽  
Rna Transfection ◽  
Normal Hepatocyte ◽  
Incidence And Mortality ◽  
Cell Progression ◽  
Hcc Cells

Abstract Background: Hepatocellular carcinoma (HCC) is still a major health burden in China considering its high incidence and mortality. Long non-coding RNAs (lncRNAs) were found playing vital roles in tumor progression, suggesting a new way of diagnosis and prognosis prediction, or treatment of HCC. This study was designed to investigate the role of HIF1A-AS1 during the progression of HCC, and to explore its related mechanisms. Methods: The expression of HIF1A-AS1 was detected in 50 paired carcinoma tissues and adjacent normal tissues by quantitative real-time PCR assay. HCC cells apoptosis was induced by nutrient-deficient culture medium, and detected by Cell Counting Kit‐8 and flow cytometer assays. HIF1A-AS1 inhibition in HCC cells was accomplished by small interfering RNA transfection. Results: HIF1A-AS1 was overexpressed in HCC tissues and was associated with tumor size, TNM stage and lymph node metastasis. Compared with low HIF1A-AS1 group, high HIF1A-AS1 group had a shorter overall survival and a worse disease-free survival. HIF1A-AS1 expression was significantly higher in HCC cell lines (7721 and Huh7) than that in normal hepatocyte cell line L02 under normal culture condition. However, under nutrient-deficient condition, HIF1A-AS1 expression was significantly increased in both HCC and normal hepatocyte cell lines, and was increased with the prolongation of nutrient-free culture. inhibition of HIF1A-AS1 promoted starvation-induced HCC cells apoptosis. Furthermore, inhibition of HIF1A-AS1 could also reduce starvation-induced HCC cells autophagy. The expression of HIF-1α and phosphorylated mTOR was significantly decreased in HCC cells after HIF1A-AS1 inhibition. Conclusions: HIF1A-AS1, overexpressed in HCC and associated with HCC prognosis, could regulate starvation-induced HCC cells apoptosis by reducing HIF-1α/mTOR mediated autophagy, promoting HCC cell progression. Trial registration: This research is retrospectively registered.

scholarly journals ORC6, Negatively Regulated by miR-1-3p, Promotes Proliferation, Migration, and Invasion of Hepatocellular Carcinoma Cells

2021 ◽  
Vol 9 ◽  
Author(s):  
Hu Chen ◽  
Lequn Bao ◽  
Jianhua Hu ◽  
Dongde Wu ◽  
Xianli Tong
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle ◽  
Cell Lines ◽  
Cell Cycle Progression ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Regulatory Function ◽  
Migration And Invasion ◽  
Cycle Progression ◽  
Hcc Cells

BackgroundIn recent years, microRNA-1-3p (miR-1-3p) has been linked to the progression of multiple cancers, whereas little is known about its role in hepatocellular carcinoma (HCC). Herein, we investigated the function of miR-1-3p in HCC, and its regulatory function on origin recognition complex subunit 6 (ORC6).MethodsQuantitative real-time polymerase chain reaction (qRT-PCR) was performed for detecting the expression levels of miR-1-3p and ORC6 mRNA in HCC samples and cell lines. ORC6 expression at the protein level was quantified by Western blot. After gain-of-function and loss-of-function models were established, cell counting kit-8 (CCK-8) assays, Transwell assays, flow cytometry, and 5-Ethynyl-2′-deoxyuridine (EdU) assay were performed for examining cell proliferation, migration, invasion, cell cycle, and apoptosis. The targeting relationship between miR-1-3p and ORC6 was confirmed with bioinformatic analysis and dual-luciferase reporter assays.ResultsThe expression of miR-1-3p was reduced in HCC samples and cell lines. Overexpression of miR-1-3p suppressed the proliferation, migration, and invasion, and induced cell-cycle arrest and apoptosis of HCC cells, whereas the opposite effects were induced by miR-1-3p inhibition. ORC6 is identified as a novel target of miR-1-3p, the expression of which is negatively correlated with miR-1-3p expression in HCC tissues. ORC6 overexpression facilitated the proliferation, migration, invasion, and cell cycle progression, and reduced apoptosis of HCC cells, whereas the opposite effects were induced by ORC6 knockdown. What is more, ORC6 overexpression counteracted the biological functions of miR-1-3p in HCC cells.ConclusionMiR-1-3p targets ORC6 to suppress the proliferation, migration, invasion, and cell cycle progression, and promote apoptosis of HCC cells.

scholarly journals LncRNA SLC16A1-AS1 Contributes to the Progression of Hepatocellular Carcinoma Cells by Modulating miR-411/MITD1 Axis

2021 ◽  
Author(s):  
Chun Duan ◽  
Bin Quan ◽  
Ni Wang ◽  
Jianghua Yang ◽  
Yan-Lin Yu
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Lines ◽  
Carcinoma Cells ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
High Morbidity ◽  
Transwell Assay ◽  
Downstream Target ◽  
Common Malignancy ◽  
Hcc Cells

Abstract Background: Hepatocellular carcinoma (HCC) is a common malignancy with high morbidity. The current study aimed to explore the molecular mechannism of lncRNA SLC16A1-AS1 in the tumorigenesis of HCC.Material and Methods: The expression of SLC16A1-AS1 and miR-411 were examined in clinical HCC tissues. HCC cell lines Hep3B and Huh-7 were employed and transfected with si-SLC16A1-AS1. The correlation between SLC16A1-AS1 and miR-411 was verified by luciferase reporter assay. Cell viability was detected by CCK-8 assay. Cell migration and invasion capacity were examined by transwell assay. The protein level of MITD1 was analyzed by western blotting.Results: The expression of SLC16A1-AS1 markedly increased in HCC tissues and cell lines. Subsequent studies identified SLC16A1-AS1 as a downstream target of miR-411. In addition, SLC16A1-AS1 knockdown and miR-411 overexpression significantly stagnated progression of HCC cells. SLC16A1-AS1 knockdown also downregulated MITD1 levels. Conclusion: Our findings showed that SLC16A1-AS1 was overexpressed in HCC cells and tissues. SLC16A1-AS1 promoted the malignant characteristics of HCC cells and acted as an oncogene. Its regulatory effect may be associated with miR-411/MITD1 axis. Therefore, SLC16A1-AS1 has a potential be used as a biomarker or therapeutic target for the treatment of HCC.

scholarly journals Inhibition of HIF1A-AS1 promoted starvation-induced hepatocellular carcinoma cells apoptosis by reducing HIF-1α/mTOR mediated autophagy

2020 ◽  
Author(s):  
Fenfen Hong ◽  
Yang Li ◽  
Yu Gao ◽  
Linfeng Zheng ◽  
Xianpeng Li ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Lines ◽  
Disease Free Survival ◽  
Cell Counting ◽  
Normal Tissues ◽  
Rna Transfection ◽  
Normal Hepatocyte ◽  
Incidence And Mortality ◽  
Cell Progression ◽  
Hcc Cells

Abstract Background: Hepatocellular carcinoma (HCC) is still a major health burden in China considering its high incidence and mortality. Long non-coding RNAs (lncRNAs) were found playing vital roles in tumor progression, suggesting a new way of diagnosis and prognosis prediction, or treatment of HCC. This study was designed to investigate the role of HIF1A-AS1 during the progression of HCC, and to explore its related mechanisms. Methods: The expression of HIF1A-AS1 was detected in 50 paired carcinoma tissues and adjacent normal tissues by quantitative real-time PCR assay. HCC cells apoptosis was induced by nutrient-deficient culture medium, and detected by Cell Counting Kit‐8 and flow cytometer assays. HIF1A-AS1 inhibition in HCC cells was accomplished by small interfering RNA transfection. Results: HIF1A-AS1 was overexpressed in HCC tissues and was associated with tumor size, TNM stage and lymph node metastasis. Compared with low HIF1A-AS1 group, high HIF1A-AS1 group had a shorter overall survival and a worse disease-free survival. HIF1A-AS1 expression was significantly higher in HCC cell lines (7721 and Huh7) than that in normal hepatocyte cell line L02 under normal culture condition. However, under nutrient-deficient condition, HIF1A-AS1 expression was significantly increased in both HCC and normal hepatocyte cell lines, and was increased with the prolongation of nutrient-free culture. inhibition of HIF1A-AS1 promoted starvation-induced HCC cells apoptosis. Furthermore, inhibition of HIF1A-AS1 could also reduce starvation-induced HCC cells autophagy. The expression of HIF-1α and phosphorylated mTOR was significantly decreased in HCC cells after HIF1A-AS1 inhibition. Conclusions: HIF1A-AS1, overexpressed in HCC and associated with HCC prognosis, could regulate starvation-induced HCC cells apoptosis by reducing HIF-1α/mTOR mediated autophagy, promoting HCC cell progression. Trial registration: This research is retrospectively registered.

scholarly journals Histone Methyltransferase G9a-Promoted Progression of Hepatocellular Carcinoma Is Targeted by Liver-Specific Hsa-miR-122

Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2376
Author(s):  
Lan-Ting Yuan ◽  
Wei-Jiunn Lee ◽  
Yi-Chieh Yang ◽  
Bo-Rong Chen ◽  
Ching-Yao Yang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Lines ◽  
Colony Formation ◽  
Disease Free Survival ◽  
Histone Methyltransferase ◽  
Control Group ◽  
Functional Evaluation ◽  
Expression Levels ◽  
Liver Cancers ◽  
Hcc Cells

Hepatocellular carcinoma (HCC) accounts for the majority of primary liver cancers, which is the second most lethal tumor worldwide. Epigenetic deregulation is a common trait observed in HCC. Recently, increasing evidence suggested that the G9a histone methyltransferase might be a novel regulator of HCC development. However, several HCC cell lines were recently noted to have HeLa cell contamination or to have been derived from non-hepatocellular origin, suggesting that functional validation of G9a in proper HCC models is still required. Herein, we first confirmed that higher G9a messenger RNA and protein expression levels were correlated with poor overall survival (OS) and disease-free survival (DFS) rates of HCC patients from The Cancer Genome Atlas (TCGA) dataset and our recruited HCC cohort. In an in vitro functional evaluation of HCC cells, HCC36 (hepatitis B virus-positive (HBV+) and Mahlavu (HBV−)) cells showed that G9a participated in promoting cell proliferation, colony formation, and migration/invasion abilities. Moreover, orthotopic inoculation of G9a-depleted Mahlavu cells in NOD-SCID mice also resulted in a significantly decreased tumor burden compared to the control group. Furthermore, after surveying microRNA (miRNA; miR) prediction databases, we identified the liver-specific miR-122 as a G9a-targeting miRNA. In various HCC cell lines, we observed that miR-122 expression levels tended to be inversely correlated to G9a expression levels. In clinical HCC specimens, a significant inverse correlation of miR-122 and G9a mRNA expression levels was also observed. Functionally, the colony formation and invasive ability were attenuated in miR-122-overexpressing HCC cells. HCC patients with low miR-122 and high G9a expression levels had the worst OS and DFS rates compared to others. Together, our results confirmed the importance of altered G9a expression during HCC progression and discovered that a novel liver-specific miR-122-G9a regulatory axis exists.

scholarly journals Bromodomain-containing protein 9 promotes the growth and metastasis of human hepatocellular carcinoma by activating the TUFT1/AKT pathway

2020 ◽  
Vol 11 (9) ◽  
Author(s):  
Changwei Dou ◽  
Liankang Sun ◽  
Liang Wang ◽  
Jian Cheng ◽  
Weiding Wu ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Epithelial Mesenchymal Transition ◽  
Critical Role ◽  
Disease Free Survival ◽  
Akt Pathway ◽  
Akt Inhibitor ◽  
Mesenchymal Transition ◽  
Hep3b Cells ◽  
Hcc Cells

Abstract Bromodomain-containing protein 9 (BRD9) has a critical role in human squamous cell lung cancer, acute myeloid leukemia, and malignant rhabdoid tumors. However, the expression and biological role of BRD9 in hepatocellular carcinoma (HCC) is poorly understood. In this study, BRD9 expression was found to be elevated in HCC through data mining of public databases. Next, we confirmed that the expression of BRD9 was increased in HCC tissues compared with that in adjacent non-tumor tissues. The upregulated level of BRD9 was also observed in HCC cells in comparison to LO2 cells. The increased BRD9 expression was correlated with unfavorable clinicopathological features. A high level of BRD9 predicted a poorer overall survival and disease-free survival of HCC patients. Functionally, BRD9 overexpression facilitated the proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) of Hep3B cells. Conversely, either BRD9 depletion or pharmacological inhibition of BRD9 resulted in the reduced proliferation and invasiveness of HCCLM3 cells. In addition, the BRD9 knockdown restrained the growth and metastasis of HCCLM3 cells in vivo. Mechanistically, BRD9 positively regulated TUFT1 expression and AKT activation in HCC cells. ChIP-qPCR analysis indicated that BRD9 promoted the binding of P300 acetyltransferase to the TUFT1 promoter and epigenetically regulated TUFT1 expression by increasing H3K27Ac in the promoter. Notably, either TUFT1 knockdown or AKT inhibitor (MK2206) abrogated the promoting effects of BRD9 on the proliferation, migration, invasion, and EMT of Hep3B cells. The forced expression of TUFT1 abolished the effects of BRD9 knockdown on the growth and metastasis of HCCLM3 cells. Altogether, these data indicate that BRD9 promotes the growth and metastasis of HCC cells by activating the TUFT1/AKT pathway and may serve as a promising biomarker and therapeutic target for HCC.

scholarly journals High PPT1 expression predicts poor clinical outcome and PPT1 inhibitor DC661 enhances sorafenib sensitivity in hepatocellular carcinoma

2021 ◽  
Author(s):  
Jianjun Xu ◽  
Zhe Su ◽  
Xiang Cheng ◽  
Shaobo Hu ◽  
Wenjie Wang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Lines ◽  
T Cell Activation ◽  
Critical Role ◽  
Treatment Result ◽  
Tunel Staining ◽  
Sorafenib Treatment ◽  
Adaptive Resistance ◽  
Hcc Cells

Abstract Background Adaptive resistance and side effects of sorafenib treatment result in unsatisfied survival of patients with hepatocellular carcinoma (HCC). Palmitoyl-protein thioesterase 1 (PPT1) plays a critical role in progression of various cancers. However, its role on prognosis and immune infiltrates in HCC remains unclarified. Methods By data mining in the Cancer Genome Atlas databases, the role of PPT1 in HCC were initially investigated. Furthermore, HCC cell lines Hep 3B and Hep 1–6 were treated with DC661 against PPT1. The biological function of PPT1 was determined by CCK-8 test, colony formation assay, TUNEL staining, immunofluorescence staining, Western blotting, and PI-Annexin V apoptosis assays in vitro. Animal models of subcutaneous injection were applied to investigate the therapeutic role of targeting PPT1. Results Wefound that PPT1 levels were significantly upregulated in HCC tissues compared with normal tissues and were significantly associated with a poor prognosis. Multivariate analysis further confirmed that high expression of PPT1 was an independent risk factor for poor overall survival of HCC patients. We initially found that PPT1 was significantly upregulated in sorafenib-resistant cell lines established in this study. Upon sorafenib treatment, HCC cells acquired adaptive resistance by inducing autophagy. We found that DC661, a selective and potent small-molecule PPT1-inhibitor, induced lysosomal membrane permeability, caused lysosomal deacidification, inhibited autophagy and enhanced sorafenib sensitivity in HCC cells. Interestingly, this sensitization effect was also mediated by the induction mitochondrial pathway apoptosis. In addition, the expression level of PPT1 was associated with the immune infiltration in the HCC tumor microenvironment, and PPT1 inhibitor DC661 significantly enhanced the anti-tumor immune response by promoting dendritic cell maturation and further promoting CD8+ T cell activation. Moreover, DC661 combined with sorafenib was also very effective at treating xenograft models in immunized mice. Conclusions Our findings suggested that targeting PPT1 with DC661 in combination with sorafenib might be a novel and effective alternative therapeutic strategy for HCC.

Sign in / Sign up

Export Citation Format

Share Document