Current applications and future perspective of CRISPR/Cas9 gene editing in cancer.

Clustered regularly interspaced short palindromic repeats (CRISPR) system provides adaptive immunity against plasmids and phages in prokaryotes. This system inspires the development of a powerful genome engineering tool, the CRISPR/CRISPR-associated nuclease 9 (CRISPR/Cas9) genome editing system. Due to its high efficiency and precision, the CRISPR/Cas9 technique has been employed to explore the functions of cancer-related genes, establish tumor-bearing animal models and probe drug targets, vastly increasing our understanding of cancer genomics. Here, we review current status of CRISPR/Cas9 gene editing technology in oncological research. We first explain the basic principles of CRISPR/Cas9 gene editing and introduce several new CRISPR-based gene editing modes. We next detail the rapid progress of CRISPR screening in revealing tumorigenesis, metastasis, and drug resistance mechanisms. In addition, we introduce CRISPR/Cas9 system delivery vectors and finally demonstrate the potential of CRISPR/Cas9 engineering to enhance the effect of adoptive T cell therapy (ACT) and reduce adverse reactions.

PKCα/ZFP64/CSF1 axis resets the tumor microenvironment and fuels anti-PD1 resistance in hepatocellular carcinoma.

BACKGROUND & AIMS: Despite remarkable advances in treatment, most patients with hepatocellular carcinoma (HCC) respond poorly to anti-programmed cell death 1 (anti-PD1) therapy. A deeper insight into the tolerance mechanism of HCC against this therapy is urgently needed. METHODS: We performed next-generation sequencing, multiplex immunofluorescence, and dual-color immunohistochemistry and constructed an orthotopic HCC xenograft tumor model to identify the key gene associated with anti-PD1 tolerance. A spontaneously tumorigenic transgenic mouse model, an in vitro coculture system, mass cytometry, and multiplex immunofluorescence were used to explore the biological function of zinc finger protein 64 (ZFP64) on tumor progression and immune escape. Molecular and biochemical strategies like RNA-sequencing, chromatin immunoprecipitation-sequencing and mass spectrometry were used to gain insight into the underlying mechanisms of ZFP64. RESULTS: We showed that ZFP64 is frequently upregulated in tumor tissues from patients with anti-PD1-resistant HCC. Elevated ZFP64 drives anti-PD1 resistance by shifting macrophage polarization toward an alternative activation phenotype (M2) and fostering an inhibitory tumor microenvironment. Mechanistically, we primarily demonstrated that protein kinase C alpha (PKCα) directly phosphorylates ZFP64 at S226, leading to its nuclear translocation and the transcriptional activation of macrophage colony-stimulating factor (CSF1). HCC-derived CSF1 transforms macrophages to the M2 phenotype to drive immune escape and anti-PD1 tolerance. Notably, Gö6976, a protein kinase inhibitor, and lenvatinib, a multi-kinase inhibitor, reset the tumor microenvironment and restore sensitivity to anti-PD1 by blocking the PKCα/ZFP64/CSF1 axis. CONCLUSIONS: We propose that the PKCα/ZFP64/CSF1 axis is critical for triggering immune evasion and anti-PD1 tolerance. Inhibiting this axis with Gö6976 or lenvatinib overcomes anti-PD1 resistance in HCC. LAY SUMMARY: Despite remarkable treatment progress, most patients with hepatocellular carcinoma respond poorly to anti-PD1 therapy (a type of immunotherapy). A deeper insight into the tolerance mechanisms to this therapy is urgently needed. Herein, we unravel a previously unexplored mechanism linking tumor progression, macrophage polarization, and anti-PD1 resistance, and offer an attractive novel target for anti-PD1 combination therapy, which may benefit patients with hepatocellular carcinoma.

Role of eIF3C Overexpression in Predicting Prognosis of Intrahepatic Cholangiocarcinoma.

BACKGROUND: Elevated expression of eukaryotic initiation factor 3c (eIF3C) was recently uncovered to promote several types of cancer progression by inducing cell proliferation. Here, we aimed to assess the expression and prognostic value of eIF3C in intrahepatic cholangiocarcinoma (ICC) patients. METHODS: Expression of eIF3C was analyzed by immunohistochemistry in tissue microarrays (TMAs) containing 138 ICC and paired peritumoral tissues from ICC patients. Then, the roles of eIF3C in ICC cells were investigated by RNA interference, and the relationship between the eIF3C and KI67 expression was explored in ICC cells and tissues. Finally, the relation between the eIF3C level and clinicopathologic features of ICC was probed, and Kaplan-Meier and Cox's analyses were performed to assess the prognostic merit of eIF3C and KI67 in ICC patients. RESULTS: The expression of eIF3C was elevated in ICC tissues compared to paired peritumoral tissues, which was consistent with the result from the GEPIA database. The downregulation of eIF3C in ICC cells impaired the cellular invasion, metastasis, colony formation, and proliferation. Moreover, we further found a positive relationship between the eIF3C and KI67 expression in ICC cells and tissues. The expression of eIF3C in ICC tissues was positively correlated with lymphatic metastasis (p = 0.049), and the high level of KI67 was frequently found in ICC patients with the large tumor (p = 0.028), high serum AFP (p = 0.019), or lymphatic metastasis (p = 0.039). Notably, patients with the eIF3C or KI67 overexpression had shorter overall survival and higher disease-free survival rates than those with low expression of eIF3C or KI67, and the combination of eIF3C or KI67 expression was an independent parameter for predicting the prognosis and recurrence of ICC patients. CONCLUSIONS: Elevated eIF3C expression promotes ICC development, and combination of eIF3C and KI67 is a valuable predictor of the survival and recurrence of ICC patient.

Circular RNA circMET drives immunosuppression and anti-PD1 therapy resistance in hepatocellular carcinoma via the miR-30-5p/snail/DPP4 axis.

BACKGROUND: Amplification of chromosome 7q21-7q31 is associated with tumor recurrence and multidrug resistance, and several genes in this region are powerful drivers of hepatocellular carcinoma (HCC). We aimed to investigate the key circular RNAs (circRNAs) in this region that regulate the initiation and development of HCC. METHODS: We used qRT-PCR to assess the expression of 43 putative circRNAs in this chromosomal region in human HCC and matched nontumor tissues. In addition, we used cultured HCC cells to modify circRNA expression and assessed the effects in several cell-based assays as well as gene expression analyses via RNA-seq. Modified cells were implanted into immunocompetent mice to assess the effects on tumor development. We performed additional experiments to determine the mechanism of action of these effects. RESULTS: circMET (hsa_circ_0082002) was overexpressed in HCC tumors, and circMET expression was associated with survival and recurrence in HCC patients. By modifying the expression of circMET in HCC cells in vitro, we found that circMET overexpression promoted HCC development by inducing an epithelial to mesenchymal transition and enhancing the immunosuppressive tumor microenvironment. Mechanistically, circMET induced this microenvironment through the miR-30-5p/Snail/ dipeptidyl peptidase 4(DPP4)/CXCL10 axis. In addition, the combination of the DPP4 inhibitor sitagliptin and anti-PD1 antibody improved antitumor immunity in immunocompetent mice. Clinically, HCC tissues from diabetic patients receiving sitagliptin showed higher CD8+ T cell infiltration than those from HCC patients with diabetes without sitagliptin treatment. CONCLUSIONS: circMET is an onco-circRNA that induces HCC development and immune tolerance via the Snail/DPP4/CXCL10 axis. Furthermore, sitagliptin may enhance the efficacy of anti-PD1 therapy in a subgroup of patients with HCC.

Cancer cell-derived exosomal circUHRF1 induces natural killer cell exhaustion and may cause resistance to anti-PD1 therapy in hepatocellular carcinoma.

OBJECTIVE: Natural killer (NK) cells play a critical role in the innate antitumor immune response. Recently, NK cell dysfunction has been verified in various malignant tumors, including hepatocellular carcinoma (HCC). However, the molecular biological mechanisms of NK cell dysfunction in human HCC are still obscure. METHODS: The expression of circular ubiquitin-like with PHD and ring finger domain 1 RNA (circUHRF1) in HCC tissues, exosomes, and cell lines was detected by qRT-PCR. Exosomes were isolated from the culture medium of HCC cells and plasma of HCC patients using an ultracentrifugation method and the ExoQuick Exosome Precipitation Solution kit and then characterized by transmission electronic microscopy, NanoSight and western blotting. The role of circUHRF1 in NK cell dysfunction was assessed by ELISA. In vivo circRNA precipitation, RNA immunoprecipitation, and luciferase reporter assays were performed to explore the molecular mechanisms of circUHRF1 in NK cells. In a retrospective study, the clinical characteristics and prognostic significance of circUHRF1 were determined in HCC tissues. RESULTS: Here, we report that the expression of circUHRF1 is higher in human HCC tissues than in matched adjacent nontumor tissues. Increased levels of circUHRF1 indicate poor clinical prognosis and NK cell dysfunction in patients with HCC. In HCC patient plasma, circUHRF1 is predominantly secreted by HCC cells in an exosomal manner, and circUHRF1 inhibits NK cell-derived IFN-γ and TNF-α secretion. A high level of plasma exosomal circUHRF1 is associated with a decreased NK cell proportion and decreased NK cell tumor infiltration. Moreover, circUHRF1 inhibits NK cell function by upregulating the expression of TIM-3 via degradation of miR-449c-5p. Finally, we show that circUHRF1 may drive resistance to anti-PD1 immunotherapy in HCC patients. CONCLUSIONS: Exosomal circUHRF1 is predominantly secreted by HCC cells and contributes to immunosuppression by inducing NK cell dysfunction in HCC. CircUHRF1 may drive resistance to anti-PD1 immunotherapy, providing a potential therapeutic strategy for patients with HCC.

Emergency percutaneous thoracic endovascular aortic repair for patients with traumatic thoracic aortic blunt injury: A single center experience.

PURPOSE: To analyze the efficacy and outcome of percutaneous thoracic endovascular aortic repair (TEVAR) in patients with traumatic blunt aortic injury in our single-center. METHODS: From January 2014 to December 2018, a total of 89 patients with traumatic blunt aortic injuries were treated with emergency TEVAR in our center. Their clinical data such as demographics, operative details and postprocedure outcomes were analyzed retrospectively in this study using SPSS 20 software. Continuous variables were expressed as mean and standard deviation or median and interquartile range. Categorical variables are expressed as the numbers and percentages of patients. RESULTS: The median age of the patients was 37 years, and 76 (85.4%) were males. All the patients were involved in violent accidents and combined with associated injuries. Two patients died while awaiting the operations and 87 patients underwent emergency percutaneous TEVAR, with a 100% technique success. The mean time interval from admission to operating room was (90.1 ± 18.7) min, and the mean procedure time was (54.6 ± 11.9) min. Eighty (92.0%) patients were operated on under local anesthesia, while other 7 (8.0%) patients were under general anesthesia. Two cases underwent open repair of the femoral arteries because of the pseudoaneurysm formation of the access vessels. A total of 98 aortic covered stent grafts were deployed, of which 11 patients used two stent grafts (all in dissection cases). The length of the stent was (177.5 ± 24.6) mm. The horizontal diameter of aorta arch at the proximal left subclavian artery ostium was (24.9 ± 2.4) mm, the proximal diameter of the covered stent was (30.5 ± 2.6) mm, and the oversize rate of proximal site was (22.7 ± 4.0)%. The proximal landing zone length was (14.1 ± 5.5) mm. The left subclavian artery ostium was completely covered in 5 patients and partially covered in 32 patients. No blood flow reconstruction was performed. The overall aortic-related mortality was 2.25% (2/89). Among 87 patients, the median follow-up time was 24 months. Postoperative computed tomography angiography scans demonstrated no residual pseudoaneurysm, hematoma or endoleak. One patient complained of mild left upper limb weakness during follow-up due to left subclavian artery occlusion. Neither late death, nor neurological or other complications occurred. CONCLUSION: Emergency percutaneous endovascular repair is a less invasive and effective approach for the treatment of traumatic blunt aortic injuries. Long-term results remain to be further followed.

LncRNA SNHG3 induces EMT and sorafenib resistance by modulating the miR-128/CD151 pathway in hepatocellular carcinoma.

Dysregulation of long noncoding RNAs (lncRNAs) plays important roles in carcinogenesis and tumor progression, including hepatocellular carcinoma (HCC). Small nucleolar RNA host gene 3 (SNHG3) has been considered as an lncRNA to be associated with a poor prognosis in patients with HCC. Here, we reported that SNHG3 expression was significantly higher in the highly metastatic HCC (HCCLM3) cells compared with the lowly metastatic HCC cells (Hep3B and PLC/PRF/5). Furthermore, forced expression of SNHG3 promoted cell invasion, epithelial-mesenchymal transition (EMT), and sorafenib resistance in HCC. Moreover, SNHG3 overexpression induced HCC cells EMT via miR-128/CD151 cascade activation. Clinically, our data revealed that increased SNHG3 expression is correlated with poor HCC survival outcomes and sorafenib response. These data suggest that SNHG3 may be a novel therapeutic target and a biomarker for predicting response to sorafenib treatment of HCC.

The long noncoding RNA NORAD enhances the TGF-ß pathway to promote hepatocellular carcinoma progression by targeting miR-202-5p.

Hepatocellular carcinoma (HCC) is one of the most fatal cancers with common features of invasion and metastasis. Recent evidence indicate that the long noncoding RNA NORAD is a potential oncogene and is significantly upregulated in several cancers. However, the general biological role and clinical value of NORAD in HCC remains unknown. Here, NORAD expression was measured in 29 paired tumor and paratumor tissues via quantitative real-time polymerase chain reaction (qPCR). The effects of NORAD on HCC cell malignant potential were investigated via NORAD overexpression and knockdown both in vitro and in vivo. The mechanism of competitive endogenous RNAs (ceRNAs) was acquired and identified by bioinformatics analyses and luciferase assays. Moreover, the impact of NORAD level on the transforming growth factor ß (TGF-ß) pathway was further determined by qPCR. We found that HCC tissues had a high level of NORAD compared with the paratumor tissues, and NORAD upregulation was associated with the shorter overall survival of patients with HCC. Furthermore, NORAD overexpression was demonstrated to promote HCC cell migration and invasion. Mechanically, NORAD might function as a ceRNA to regulate miR-202-5p, which served as a tumor-suppressing microRNA via the TGF-ß pathway. We address that NORAD has a tumor-promoting effect in HCC and describes a novel mechanism whereby NORAD regulates the TGF-ß pathway as a ceRNA of Homo sapiens (hsa)-miR-202-5p.

Circular RNA circTRIM33-12 acts as the sponge of MicroRNA-191 to suppress hepatocellular carcinoma progression.

BACKGROUND: Recently, the dysregulation of circular RNA (circRNA) have been shown to have important regulatory roles in cancer development and progression, including hepatocellular carcinoma (HCC). However, the roles of most circRNAs in HCC are still unknown. METHODS: The expression of circular tripartite motif containing 33-12 (circTRIM33-12) in HCC tissues and cell lines was detected by qRT-PCR. The role of circTRIM33-12 in HCC progression was assessed by western blotting, CCK-8, flow cytometry, transwell and a subcutaneous tumor mouse assays both in vitro and in vivo. In vivo circRNA precipitation, RNA immunoprecipitation, luciferase reporter assays were performed to evaluate the interaction between circTRIM33-12 and miR-191. RESULTS: Here, we found that circTRIM33-12, is downregulated in HCC tissues and cell lines. The downregulation of circTRIM33-12 in HCC was significantly correlated with malignant characteristics and served as an independent risk factor for the overall survival (OS) and recurrence-free survival (RFS) of patients with HCC after surgery. The reduced expression of circTRIM33-12 in HCC cells increases tumor proliferation, migration, invasion and immune evasion. Mechanistically, we demonstrated that circTRIM33-12 upregulated TET1 expression by sponging miR-191, resulting in significantly reduced 5-hydroxymethylcytosine (5hmC) levels in HCC cells. CONCLUSIONS: These results reveal the important role of circTRIM33-12 in the proliferation, migration, invasion and immune evasion abilities of HCC cells and provide a new perspective on circRNAs in HCC progression.

Ubiquitin-specific protease 7 accelerates p14(ARF) degradation by deubiquitinating thyroid hormone receptor-interacting protein 12 and promotes hepatocellular carcinoma progression.

UNLABELLED: The prognosis for hepatocellular carcinoma (HCC) remains dismal in terms of overall survival (OS), and its molecular pathogenesis has not been completely defined. Here, we report that expression of deubiquitylase ubiquitin-specific protease 7 (USP7) is higher in human HCC tissues than in matched peritumoral tissues. Ectopic USP7 expression promotes growth of HCC cells in vivo and in vitro. Mechanistically, USP7 overexpression fosters HCC cell growth by forming a complex with and stabilizing thyroid hormone receptor-interacting protein 12 (TRIP12), which induces constitutive p14(ARF) ubiquitination. Clinically, USP7 overexpression is significantly correlated with a malignant phenotype, including larger tumor size, multiple tumor, poor differentiation, elevated alpha-fetoprotein, and microvascular invasion. Moreover, overexpression of USP7 and/or TRIP12 correlates with shorter OS and higher cumulative recurrence rates of HCC. CONCLUSION: USP7 stabilizes TRIP12 by deubiquitination, thus constitutively inactivating p14(ARF) and promoting HCC progression. This represents a novel marker for predicting prognosis and a potential therapeutic target for HCC.

Adjuvant antiviral therapy for hepatitis B virus-related hepatocellular carcinoma after curative treatment: A systematic review and meta-analysis.

AIM: To investigate whether adjuvant antiviral treatment could improve prognosis and entecavir is the optimal nucleoside/nucleotide analog (NA) regimen after curative therapy of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). METHODS: A comprehensive electronic search was performed. All controlled trials comparing antiviral treatment with placebo or no treatment for HBV-related HCC after curative treatment were included. The pooled hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Stata 12.0 software. An indirect treatment comparison method was used to compare the relative efficacy of different NA strategies. RESULTS: Twenty-one studies containing 8072 patients were included. NA was found to significantly improve recurrence-free survival (RFS) and overall survival (OS). Alternatively, for interferon, a non-significant benefit was found. By adjusted indirect comparisons among entecavir, lamivudine and adefovir, entecavir were found to display almost but not significant superiority to the other NA in improving RFS. No tendency favoring a specific NA regimen was found for OS. CONCLUSION: In HBV-HCC patient after curative treatment, NA improve the prognosis significantly but the role of interferon remains to be elucidated; entecavir was not found to be superior to other NA based on available data.

CXCL5 contributes to tumor metastasis and recurrence of intrahepatic cholangiocarcinoma by recruiting infiltrative intratumoral neutrophils.

CXCL5 is a member of the CXC-type chemokine family that may play a role in carcinogenesis and cancer progression. This study investigates the biological function and clinical significance of CXCL5 in intrahepatic cholangiocarcinoma (ICC). We demonstrated that CXCL5 was overexpressed in ICC cell lines and tumor samples compared with paired normal tissues. CXCL5 had a direct chemoattractant effect on neutrophils in vitro through PI3K-Akt and extracellular signal-regulated kinase 1/2 signaling pathways. In animal studies, CXCL5 promoted tumor growth and metastasis without altering in vitro proliferative and invasive ability of ICC cells, and this effect was mediated by the recruitment of intratumoral infiltrative neutrophils by tumor-derived CXCL5. Immunohistochemical analysis of ICC samples showed that overexpression of CXCL5 correlated strongly with intratumoral neutrophil infiltration, shorter overall survival and high tumor recurrence. Multivariate analysis revealed that CXCL5 overexpression alone, or combined with the presence of intratumoral neutrophils, was an independent prognostic indicator for ICC. In conclusion, our data showed that CXCL5 promotes ICC growth and metastasis by recruiting intratumoral neutrophils. CXCL5 alone or combined with intratumoral neutrophils is a novel prognostic predictor for ICC patients and a potential therapeutic target.

αB-crystallin complexes with 14-3-3ζ to induce epithelial-mesenchymal transition and resistance to sorafenib in hepatocellular carcinoma.

UNLABELLED: The overall survival of patients with hepatocellular carcinoma (HCC) remains poor, and the molecular pathogenesis remains incompletely defined in HCC. Here we report that increased expression of αB-Crystallin in human HCC predicts poor survival and disease recurrence after surgery. Multivariate analysis identifies αB-Crystallin expression as an independent predictor for postoperative recurrence and overall survival. We show that elevated expression of αB-Crystallin promotes HCC progression in vivo and in vitro. We demonstrate that αB-Crystallin overexpression fosters HCC progression by inducing epithelial-mesenchymal transition (EMT) in HCC cells through activation of the extracellular-regulated protein kinase (ERK) cascade, which can counteract the effect of sorafenib. αB-Crystallin complexes with and elevates 14-3-3ζ protein, leading to up-regulation of ERK1/2 activity. Moreover, overexpression of αB-Crystallin in HCC cells induces EMT progression through an ERK1/2/Fra-1/slug signaling pathway. Clinically, our data reveal that overexpression of both αB-Crystallin and 14-3-3ζ correlates with the HCC poorest survival outcomes, and sorafenib response is impaired in patients with αB-Crystallin overexpression. CONCLUSION: These data suggest that the αB-Crystallin-14-3-3ζ complex acts synergistically to promote HCC progression by constitutively activating ERK signaling. This study reveals αB-Crystallin as a potential therapeutic target for HCC and a biomarker for predicting sorafenib treatment response. (HEPATOLOGY 2013).

Macro CD5L+ deteriorates CD8+T cells exhaustion and impairs combination of Gemcitabine-Oxaliplatin-Lenvatinib-anti-PD1 therapy in intrahepatic cholangiocarcinoma.

Intratumoral immune status influences tumor therapeutic response, but it remains largely unclear how the status determines therapies for patients with intrahepatic cholangiocarcinoma. Here, we examine the single-cell transcriptional and TCR profiles of 18 tumor tissues pre- and post- therapy of gemcitabine plus oxaliplatin, in combination with lenvatinib and anti-PD1 antibody for intrahepatic cholangiocarcinoma. We find that high CD8 GZMB+ and CD8 proliferating proportions and a low Macro CD5L+ proportion predict good response to the therapy. In patients with a poor response, the CD8 GZMB+ and CD8 proliferating proportions are increased, but the CD8 GZMK+ proportion is decreased after the therapy. Transition of CD8 proliferating and CD8 GZMB+ to CD8 GZMK+ facilitates good response to the therapy, while Macro CD5L+-CD8 GZMB+ crosstalk impairs the response by increasing CTLA4 in CD8 GZMB+. Anti-CTLA4 antibody reverses resistance of the therapy in intrahepatic cholangiocarcinoma. Our data provide a resource for predicting response of the combination therapy and highlight the importance of CD8+T-cell status conversion and exhaustion induced by Macro CD5L+ in influencing the response, suggesting future avenues for cancer treatment optimization.

Oncogenic miR-93-5p/Gal-9 axis drives CD8 (+) T-cell inactivation and is a therapeutic target for hepatocellular carcinoma immunotherapy.

Evading immune destruction is an emerging hallmark of cancer and a potential key step in tumorigenesis. Immune checkpoint blocker (ICB)-based combination therapies revolutionize the landscape of systemic therapy for HCC. However, the molecular underpinnings governing immune evasion and responses remain unclear. Our study aims to find new regulatory molecules that drive HCC immune escape and tumorigenesis and find new promising immunotherapeutic approaches for HCC. In our study, laser capture microdissection (LCM) and miRNA sequencing combined with in vitro and in vivo experiments identified miR-93-5p as a crucial initiating oncogene during liver progenitor cell (LPC) malignant transformation and immune escape. Mechanistically, miR-93-5p could directly target canonical tumour suppressors such as APC to promote LPC malignant transformation and hepatocarcinogenesis. More importantly, miR-93-5p could induce deviant GAL-9 augmentation to inactivate infiltrated CD8(+) T cells and induce immune evasion by targeting several epigenetic regulators, such as AEBP2, and then regulating H3K4me3/H3K27me3 bivalency. Experiments in C57BL/6 mice demonstrated that blockade of Gal-9 abrogated miR-93-5p-induced HCC progression and improved their prognosis. Clinically, we identified a unique subtype of HCC closely associated with high GAL-9 expression and anti-PD1 treatment resistance. Our study highlights the pivotal role of the miR-93-5p/Gal-9 axis in driving HCC immune escape and tumorigenesis. Blocking GAL-9 is an effective and promising immunotherapeutic approach for HCC.

Loss of 5-hydroxymethylcytosine induces chemotherapy resistance in hepatocellular carcinoma via the 5-hmC/PCAF/AKT axis.

Multidrug resistance is a major challenge in treating advanced hepatocellular carcinoma (HCC). Although recent studies have reported that the multidrug resistance phenotype is associated with abnormal DNA methylation in cancer cells, the epigenetic mechanism underlying multidrug resistance remains unknown. Here, we reported that the level of 5-hydroxymethylcytosine (5-hmC) in human HCC tissues was significantly lower than that in adjacent liver tissues, and reduced 5-hmC significantly correlated with malignant phenotypes, including poor differentiation and microvascular invasion; additionally, loss of 5-hmC was related to chemotherapy resistance in post-transplantation HCC patients. Further, the 5-hmC level was regulated by ten-eleven translocation 2 (TET2), and the reduction of TET2 in HCC contributes to chemotherapy resistance through histone acetyltransferase P300/CBP-associated factor (PCAF) inhibition and AKT signaling hyperactivation. In conclusion, loss of 5-hmC induces chemotherapy resistance through PCAF/AKT axis and is a promising chemosensitivity prediction biomarker and therapeutic target for HCC patients.

The clinical implications and molecular features of intrahepatic cholangiocarcinoma with perineural invasion.

BACKGROUND: Perineural invasion (PNI) is associated with metastasis in malignancies, including intrahepatic cholangiocarcinoma (ICC), and is correlated with poor prognosis. METHODS: The study included three large cohorts: ZS-ICC and TMA cohorts from our team, MSK cohort from a public database, and a small cohort named cohort 4. Prognostic implications of PNI were investigated in MSK cohort and TMA cohort. PNI-related genomic and transcriptomic profiles were analyzed in MSK and ZS-ICC cohorts. GO, KEGG, and ssGSEA analyses were performed. Immunohistochemistry was used to investigate the relationship between PNI and markers of neurons, hydrolases, and immune cells. The efficacy of adjuvant therapy in ICC patients with PNI was also assessed. RESULTS: A total of 30.6% and 20.7% ICC patients had PNI in MSK and TMA cohorts respectively. Patients with PNI presented with malignant phenotypes such as high CA19-9, the large bile duct type, lymph node invasion, and shortened overall survival (OS) and relapse-free survival (RFS). Nerves involved in PNI positively express tyrosine hydroxylase (TH), a marker of sympathetic nerves. Patients with PNI showed high mutation frequency of KRAS and an immune suppressive metastasis prone niche of decreased NK cell, increased neutrophil, and elevated PD-L1, CD80, and CD86 expression. Patients with PNI had an extended OS after adjuvant therapy with TEGIO, GEMOX, or capecitabine. CONCLUSION: Our study deciphered the genomic features and the immune suppressive metastasis-prone niche in ICC with PNI. Patients with PNI showed a poor prognosis after surgery but a good response to adjuvant chemotherapy.