An acid trip activates protumoral macrophages to promote hepatocellular carcinoma malignancy

Tumor-associated macrophages (TAMs) promote metastasis and tumor cell extravasation, survival, and growth. In hepatocellular carcinoma (HCC), the presence of TAM subpopulations correlates with poor outcome. In this issue of the JCI, Ning et al. report on their use of cell culture, mouse models, and human data sets to investigate the interactions between aerobic glycolysis and carbonic anhydrase XII (CA12) expression in HCC. Aerobic glycolysis promoted CA12 upregulation in TAMs, which induced a protumoral phenotype to promote tumor growth and metastasis. Tumor cell factors derived from HCC samples induced CA12 upregulation in tumor-infiltrating TAMs via the HIF1α pathway. In preclinical models of HCC, CA12 inhibition reduced tumor growth and lung metastasis and reduced TAM infiltrate. Notably, dual treatment with anti-PD1 and CA12 inhibitors synergistically attenuated tumor growth and metastasis and enhanced survival compared with either treatment alone. These findings suggest that targeting CA12 in combination with immune-checkpoint blockade may provide treatment options for HCC.     

BSA–MnO2–SAL multifunctional nanoparticle-mediated M1 macrophages polarization for glioblastoma therapy

Glioblastoma (GBM) is a type of brain tumour with a very high fatality rate. Owing to the presence of the blood–brain barrier (BBB), it is difficult for drugs to reach the tumour site; thus, there has been little progress in GBM chemotherapeutics. Furthermore, the malignant growth of tumours largely depends on the tumour microenvironment. GBM is especially prevalent in slightly acidic, hydrogen peroxide (H₂O₂)-rich, hypoxic, and immunosuppressive microenvironments. Tumour-supporting macrophages (M₂ macrophages) are a type of immune cell that promote tumour growth. Therefore, targeting M₂ macrophages and repolarizing them into tumour-suppressor macrophages (M₁ macrophages) are important strategies for GBM treatment. Salinomycin (SAL) is an anti-tumour drug that can improve the tumour immune microenvironment. Interestingly, we found that SAL promoted the expression of M₁ macrophages in vitro, but its ability was limited in vivo because of the presence of the BBB. In this study, we combined SAL and MnO₂ to design bovine serum albumin–MnO₂–SAL (BMS), a nanoparticle that responds to acidic and H₂O₂-rich microenvironments. Our experimental results showed that BMS reduced GBM growth efficiency and had the ability to penetrate the BBB. It also enhanced the repolarization ability of SAL owing to the production of Mn²⁺ after decomposition, which could be applied in Magnetic Resonance Imaging (MRI). This study demonstrated that the multifunctional nanoparticle BMS is of great significance in inhibiting orthotopic GBM growth and improving immunosuppressive microenvironments.

Schematic illustration of BMS induced M₁ macrophage polarization and the antitumor effect.     

Protein tyrosine phosphatase nonreceptor type 2 controls colorectal cancer development

Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) recently emerged as a promising cancer immunotherapy target. We set out to investigate the functional role of PTPN2 in the pathogenesis of human colorectal carcinoma (CRC), as its role in immune-silent solid tumors is poorly understood. We demonstrate that in human CRC, increased PTPN2 expression and activity correlated with disease progression and decreased immune responses in tumor tissues. In particular, stage II and III tumors displayed enhanced PTPN2 protein expression in tumor-infiltrating T cells, and increased PTPN2 levels negatively correlated with expression of PD-1, CTLA4, STAT1, and granzyme A. In vivo, T cell– and DC-specific PTPN2 deletion reduced tumor burden in several CRC models by promoting CD44⁺ effector/memory T cells, as well as CD8⁺ T cell infiltration and cytotoxicity in the tumor. In direct relevance to CRC treatment, T cell–specific PTPN2 deletion potentiated anti–PD-1 efficacy and induced antitumor memory formation upon tumor rechallenge in vivo. Our data suggest a role for PTPN2 in suppressing antitumor immunity and promoting tumor development in patients with CRC. Our in vivo results identify PTPN2 as a key player in controlling the immunogenicity of CRC, with the strong potential to be exploited for cancer immunotherapy.     

Expression of caspase-3 and hypoxia inducible factor 1α in hepatocellular carcinoma complicated by hemorrhage and necrosis

BACKGROUNDHepatocellular carcinoma (HCC) is a malignant tumor that occurs in the liver. Its onset is latent, and it shows high heterogeneity and can readily experience intrahepatic metastasis or systemic metastasis, which seriously affects patients’ quality of life. Numerous studies have shown that hypoxia inducible factor1α (HIF-1α) plays a significant role in the occurrence and development of tumors, as it promotes the formation of intratumoral vessels and plays a key role in their metastasis and invasion. Some studies have reported that caspase-3, which is induced by various factors, is involved in the apoptosis of tumor cells.AIMTo investigate the expression of caspase-3 and HIF-1α and their relationship to the prognosis of patients with primary HCC complicated by pathological changes of hemorrhage and necrosis.METHODSA total of 88 patients with HCC complicated by pathological changes of hemorrhage and necrosis who were treated at our hospital from January 2017 to December 2019 were selected. The expression of caspase-3 and HIF-1α in HCC and paracancerous tissues from these patients was assessed.RESULTSThe positive expression rate of caspase-3 in HCC tissues was 27.27%, which was significantly lower than that in the paracancerous tissues (P < 0.05), while the positive expression rate of HIF-1α was 72.73%, which was significantly higher than that in the paracancerous tissues (P < 0.05). The positive expression rates for caspase-3 in tumor node metastasis (TNM) stage III and lymph node metastasis tissues were 2.78% and 2.50%, respectively, which were significantly lower than those in TNM stage I-II and non-lymph node metastasis tissues (P < 0.05). The positive expression rates of HIF-1α in TNM stage III, lymph node metastasis, and portal vein tumor thrombus tissues were 86.11%, 87.50%, and 88.00%, respectively, and these values were significantly higher than those in TNM stage I-II, non-lymph node metastasis, and portal vein tumor thrombus tissues (P < 0.05). The expression of caspase-3 and HIF-1α in HCC tissues were negatively correlated (r_s = − 0.426, P < 0.05). The median overall survival time of HCC patients was 18.90 mo (95% CI: 17.20–19.91). The results of the Cox proportional risk regression model analysis showed that TNM stage, portal vein tumor thrombus, lymph node metastasis, caspase-3 expression, and HIF-1α expression were the factors influencing patient prognosis (P < 0.05).CONCLUSIONThe expression of caspase-3 decreases and HIF-1α increases in HCC tissues complicated by pathological changes of hemorrhage and necrosis, and these are related to clinicopathological features and prognosis.     

STK4 regulates TLR pathways and protects against chronic inflammation–related hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is frequently associated with pathogen infection–induced chronic inflammation. Large numbers of innate immune cells are present in HCCs and can influence disease outcome. Here, we demonstrated that the tumor suppressor serine/threonine-protein kinase 4 (STK4) differentially regulates TLR3/4/9-mediated inflammatory responses in macrophages and thereby is protective against chronic inflammation–associated HCC. STK4 dampened TLR4/9-induced proinflammatory cytokine secretion but enhanced TLR3/4-triggered IFN-β production via binding to and phosphorylating IL-1 receptor–associated kinase 1 (IRAK1), leading to IRAK1 degradation. Notably, macrophage-specific Stk4 deletion resulted in chronic inflammation, liver fibrosis, and HCC in mice treated with a combination of diethylnitrosamine (DEN) and CCl₄, along with either LPS or E. coli infection. STK4 expression was markedly reduced in macrophages isolated from human HCC patients and was inversely associated with the levels of IRAK1, IL-6, and phospho-p65 or phospho-STAT3. Moreover, serum STK4 levels were specifically decreased in HCC patients with high levels of IL-6. In STK4-deficient mice, treatment with an IRAK1/4 inhibitor after DEN administration reduced serum IL-6 levels and liver tumor numbers to levels similar to those observed in the control mice. Together, our results suggest that STK4 has potential as a diagnostic biomarker and therapeutic target for inflammation-induced HCC.     

High serum soluble CD155 level predicts poor prognosis and correlates with an immunosuppressive tumor microenvironment in hepatocellular carcinoma

BackgroundHepatocellular carcinoma (HCC) is one of the most prevalent malignancies with poor prognosis. There is no research about the clinical significance of serum soluble CD155 (sCD155) level for HCC. We aim to explore the prognostic and diagnostic value of sCD155 in HCC patients undergoing curative resection.MethodsSerum sCD155 level in HCC patients was determined by enzyme‐linked immunosorbent assay. The prognostic significance of sCD155 was evaluated by Cox regression and Kaplan–Meier analyses. CD155 expression and biomarkers of immune cells in HCC tissues were detected by immunohistochemistry staining. The diagnostic significance of sCD155 was evaluated using receiver operating characteristic curve.ResultsSerum sCD155 level was significantly increased in HCC patients and predicted poor prognosis. The prognostic value of sCD155 remained in low recurrent risk subgroups of HCC. Serum sCD155 level was positively related to CD155 expression in HCC tissues. High serum sCD155 level was associated with decreased numbers of CD8⁺T cells and CD56⁺NK cells and increased number of CD163⁺M2 macrophages. Serum sCD155 level had better performance in distinguishing HCC patients from healthy donors and patients with chronic liver conditions than α‐fetoprotein. Among patients with α‐fetoprotein ≤ 20 ng/ml, serum sCD155 level could differentiate HCC patients from non‐HCC patients.ConclusionSerum sCD155 level represents a promising biomarker for diagnosis and prognosis of HCC. High serum sCD155 level may reflect an immunosuppressive tumor microenvironment in HCC.     

Activated monocytes in peritumoral stroma of hepatocellular carcinoma foster immune privilege and disease progression through PD-L1

Macrophages (Mφ) are prominent components of solid tumors and exhibit distinct phenotypes in different microenvironments. We have recently found that tumors can alter the normal developmental process of Mφ to trigger transient activation of monocytes in peritumoral stroma. We showed that a fraction of monocytes/Mφ in peritumoral stroma, but not in cancer nests, expresses surface PD-L1 (also termed B7-H1) molecules in tumors from patients with hepatocellular carcinoma (HCC). Monocytes activated by tumors strongly express PD-L1 proteins with kinetics similar to their activation status, and significant correlations were found between the levels of PD-L1⁺ and HLA-DR^high on tumor-infiltrating monocytes. Autocrine tumor necrosis factor α and interleukin 10 released from activated monocytes stimulated monocyte expression of PD-L1. The PD-L1⁺ monocytes effectively suppressed tumor-specific T cell immunity and contributed to the growth of human tumors in vivo; the effect could be reversed by blocking PD-L1 on those monocytes. Moreover, we found that PD-L1 expression on tumor-infiltrating monocytes increased with disease progression, and the intensity of the protein was associated with high mortality and reduced survival in the HCC patients. Thus, expression of PD-L1 on activated monocytes/Mφ may represent a novel mechanism that links the proinflammatory response to immune tolerance in the tumor milieu.Tumor progression is now recognized as the product of evolving cross talk between different cell types within the tumor and its stroma (1, 2). Although normal stroma is nonpermissive for neoplastic progression, cancer cells can modulate adjacent stroma to generate a supportive microenvironment (1–3). This includes the ability to alter the ratios of effector to regulatory T cells and to affect the functions of APCs and the expression of cosignaling molecules, which in turn creates an immunosuppressive network to promote tumor progression and immune evasion (3, 4). There is also emerging evidence that the proinflammatory response at the tumor stroma can be rerouted in a tumor-promoting direction (5). These observations suggest that different tumor microenvironments can create either immune suppression or activation at distinct sites to promote tumor progression.Macrophages (Mφ) constitute a major component of the leukocyte infiltrate in tumor stroma. These cells are derived almost entirely from circulating monocytes, and in response to environmental signals, they acquire special phenotypic characteristics that are associated with diverse functions (6–8). We have recently found that tumor environments can alter the normal development of Mφ that is intended to trigger transient early activation of monocytes in the peritumoral region (7). Furthermore, in a study of patients with hepatocellular carcinoma (HCC) (5), it was noted that an increased number of activated monocytes/Mφ (HLA-DR^highCD68⁺ cells) in the liver was associated with progression of the disease. Thus, immune functional data of activated monocytes/Mφ in cancer environments are essential for understanding their roles and potential mechanisms in tumor immunopathogenesis.PD-L1 (also termed B7-H1 and CD274) is a member of the B7 family of cosignaling molecules, and it possesses the dual functions of co-stimulation of naive T cells via an as yet unidentified receptor and coinhibition of activated effector T cells through PD-1 receptor (4, 9, 10). Expression of PD-L1 (B7-H1) is often induced or maintained by many inflammatory cytokines (4, 11), of which IFN-γ is the most potent. In addition to being expressed on activated immune cells, most human cancers also express high levels of PD-L1 (B7-H1) protein, which correlates with poor prognosis in some cases (4, 11–13). In contrast, low or rare PD-L1 (B7-H1) expression is observed in most mouse and human tumor cell lines, possibly because of the lack of a complete cancer microenvironment in cell lines in vitro (4, 12). At present, little is known about the expression and function of PD-L1 (B7-H1) on APCs in the inflammatory activated stroma of human tumors in situ.HCC is the fifth most common cancer worldwide, with an extremely poor prognosis (14). By using HCC as a model system, the present study showed that PD-L1⁺ monocytes were accumulated in the peritumoral stroma area of cancers and increased with tumor progression. The pattern of PD-L1 (B7-H1) expression coincided with the transient activation of monocytes/Mφ during their initial exposure to the tumor environment. These activated PD-L1⁺ monocytes suppressed tumor-specific T cell immunity, and their high infiltration was associated with poor survival of the HCC patients. Moreover, we found that blocking PD-L1 (B7-H1) effectively attenuated this monocyte-mediated T cell anergy and restored their antitumor activity in vivo. Therefore, PD-L1 (B7-H1) expression on activated monocytes may represent a novel mechanism by which the proinflammatory response is linked to immune tolerance in the tumor milieu.     

Targeting HIF-1α abrogates PD-L1–mediated immune evasion in tumor microenvironment but promotes tolerance in normal tissues

A combination of anti–CTLA-4 plus anti–PD-1/PD-L1 is the most effective cancer immunotherapy but causes high incidence of immune-related adverse events (irAEs). Here we report that targeting of HIF-1α suppressed PD-L1 expression on tumor cells and tumor-infiltrating myeloid cells, but unexpectedly induced PD-L1 in normal tissues by an IFN-γ–dependent mechanism. Targeting the HIF-1α/PD-L1 axis in tumor cells reactivated tumor-infiltrating lymphocytes and caused tumor rejection. The HIF-1α inhibitor echinomycin potentiated the cancer immunotherapeutic effects of anti–CTLA-4 therapy, with efficacy comparable to that of anti–CTLA-4 plus anti–PD-1 antibodies. However, while anti–PD-1 exacerbated irAEs triggered by ipilimumab, echinomycin protected mice against irAEs by increasing PD-L1 levels in normal tissues. Our data suggest that targeting HIF-1α fortifies the immune tolerance function of the PD-1/PD-L1 checkpoint in normal tissues but abrogates its immune evasion function in the tumor microenvironment to achieve safer and more effective immunotherapy.     

生物钟基因Per3在肝细胞癌中的表达及临床意义

目的研究生物钟基因Per3在肝细胞癌（HCC）中的表达与临床意义。 方法选取2010年1月1日至2013年12月31日在深圳市人民医院肝胆外科行肝癌根治性切除术且经病理证实的120例肝癌患者的癌组织及癌旁组织。采用免疫组化法检测肝癌和癌旁组织中Per3蛋白的表达,并分析其表达与临床病理特征的关系。采用Kaplan-Meier时间生存曲线分析Per3表达与患者预后的关系。 结果肝癌组织中Per3蛋白的表达较癌旁组织显著降低,两者比较差异具有统计学意义（χ²=13.02,P<0.01）。在肝癌组织中Per3蛋白低表达的患者肿瘤数目≥2个、瘤体>5 cm及伴门静脉侵袭的发生率显著升高,差异均具有统计学意义（χ²=12.095,P=0.001;χ²=6.305,P=0.012;χ²=4.461,P=0.035）。Per3低表达的HCC患者总体生存率（OS）与无瘤生存率（DFS）均显著降低（P=0.011、0.036）。 结论Per3蛋白在肝癌组织中呈低表达,与患者肿瘤数目、大小、门脉侵袭密切相关,并影响患者的OS和DFS,可以作为HCC患者肝切除术后的预后指标。     

Lung epithelial apoptosis in influenza virus pneumonia: the role of macrophage-expressed TNF-related apoptosis-inducing ligand

Mononuclear phagocytes have been attributed a crucial role in the host defense toward influenza virus (IV), but their contribution to influenza-induced lung failure is incompletely understood. We demonstrate for the first time that lung-recruited “exudate” macrophages significantly contribute to alveolar epithelial cell (AEC) apoptosis by the release of tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) in a murine model of influenza-induced pneumonia. Using CC-chemokine receptor 2–deficient (CCR2^−/−) mice characterized by defective inflammatory macrophage recruitment, and blocking anti-CCR2 antibodies, we show that exudate macrophage accumulation in the lungs of influenza-infected mice is associated with pronounced AEC apoptosis and increased lung leakage and mortality. Among several proapoptotic mediators analyzed, TRAIL messenger RNA was found to be markedly up-regulated in alveolar exudate macrophages as compared with peripheral blood monocytes. Moreover, among the different alveolar-recruited leukocyte subsets, TRAIL protein was predominantly expressed on macrophages. Finally, abrogation of TRAIL signaling in exudate macrophages resulted in significantly reduced AEC apoptosis, attenuated lung leakage, and increased survival upon IV infection. Collectively, these findings demonstrate a key role for exudate macrophages in the induction of alveolar leakage and mortality in IV pneumonia. Epithelial cell apoptosis induced by TRAIL-expressing macrophages is identified as a major underlying mechanism.     

Loss of SPARC in bladder cancer enhances carcinogenesis and progression

Secreted protein acidic and rich in cysteine (SPARC) has been implicated in multiple aspects of human cancer. However, its role in bladder carcinogenesis and metastasis are unclear,with some studies suggesting it may be a promoter and others arguing the opposite. Using a chemical carcinogenesis model in Sparc-deficient mice and their wild-type littermates, we found that loss of SPARC accelerated the development of urothelial preneoplasia (atypia and dysplasia), neoplasia, and metastasis and was associated with decreased survival. SPARC reduced carcinogen-induced inflammation and accumulation of reactive oxygen species as well as urothelial cell proliferation. Loss of SPARC was associated with an inflammatory phenotype of tumor-associated macrophages and fibroblasts, with concomitant increased activation of urothelial and stromal NF-κB and AP1 in vivo and in vitro. Syngeneic spontaneous and experimental metastasis models revealed that tumor- and stroma-derived SPARC reduced tumor growth and metastasis through inhibition of cancer-associated inflammation and lung colonization. In human bladder tumor tissues, the frequency and intensity of SPARC expression were inversely correlated with disease-specific survival. These results indicate that SPARC is produced by benign and malignant compartments of bladder carcinomas where it functions to suppress bladder carcinogenesis, progression, and metastasis.     

Expression of SET domain bifurcated histone lysine methyltransferase 1 and its clinical prognostic significance in hepatocellular carcinoma

BackgroundTo detect the expression of histone methyltransferase SETDB1 in hepatocellular carcinoma, and to analyze the relationship between SETDB1 expression and tumor size, microvascular invasion, pTNM stage, gender, age, tumor number, tumor differentiation, and other clinicopathological characteristics.MethodsImmunohistochemical method was used to detect the expression of SETDB1 proteins in liver cancer tissues and adjacent tissues of 100 cases. The qRT‐PCR method was used to detect the expression of SETDB1 mRNA in hepatocellular carcinoma and adjacent tissues of 64 cases.ResultsThe expression of SETDB1 protein and mRNA in hepatocellular carcinoma was higher than that of adjacent normal liver tissue (p < 0.05). High protein expression of SETDB1 was associated with tumor size, MVI presence, and pTNM stage (p < 0.05). Univariate analysis revealed that the tumor size, tumor differentiation, MVI grade, and pTNM stage were correlated with DFS, while tumor size, MVI grade, pTNM stage, and SETDB1 protein expression were correlated with OS. Multivariate analysis showed that the combination of MVI grade and pTNM stage has statistical significance in predicting prognosis, while SETDB1 protein expression was not significant prognosis factor.ConclusionsSETDB1 has a certain role in HCC progression and may act as a prognostic predictor concerning the survival of HCC patients.     

Blockade of tumor necrosis factor in collagen-induced arthritis reveals a novel immunoregulatory pathway for Th1 and Th17 cells

IL-17 is implicated in the pathogenesis of rheumatoid arthritis (RA) and has previously been shown to be induced by tumor necrosis factor (TNF) in vitro. The aim of this study was to assess the impact of TNF inhibition on IL-17 production in collagen-induced arthritis, a model of RA. TNF blockade using TNFR-Fc fusion protein or anti-TNF monoclonal antibody reduced arthritis severity but, unexpectedly, expanded populations of Th1 and Th17 cells, which were shown by adoptive transfer to be pathogenic. Th1 and Th17 cell populations were also expanded in collagen-immunized TNFR p55^−/− but not p75^−/− mice. The expression of IL-12/IL-23 p40 was up-regulated in lymph nodes (LN) from p55^−/− mice, and the expansion of Th1/Th17 cells was abrogated by blockade of p40. Treatment of macrophages with rTNF also inhibited p40 production in vitro. These findings indicate that at least one of the ways in which TNF regulates Th1/Th17 responses in arthritis is by down-regulating the expression of p40. Finally, although TNF blockade increased numbers of Th1 and Th17 cells in LN, it inhibited their accumulation in the joint, thereby providing an explanation for the paradox that anti-TNF therapy ameliorates arthritis despite increasing numbers of pathogenic T cells.     

HIF inhibitor 32-134D eradicates murine hepatocellular carcinoma in combination with anti-PD1 therapy

Hepatocellular carcinoma (HCC) is a major cause of cancer mortality worldwide and available therapies, including immunotherapies, are ineffective for many patients. HCC is characterized by intratumoral hypoxia, and increased expression of hypoxia-inducible factor 1α (HIF-1α) in diagnostic biopsies is associated with patient mortality. Here we report the development of 32-134D, a low-molecular-weight compound that effectively inhibits gene expression mediated by HIF-1 and HIF-2 in HCC cells, and blocks human and mouse HCC tumor growth. In immunocompetent mice bearing Hepa1-6 HCC tumors, addition of 32-134D to anti-PD1 therapy increased the rate of tumor eradication from 25% to 67%. Treated mice showed no changes in appearance, behavior, body weight, hemoglobin, or hematocrit. Compound 32-134D altered the expression of a large battery of genes encoding proteins that mediate angiogenesis, glycolytic metabolism, and responses to innate and adaptive immunity. This altered gene expression led to significant changes in the tumor immune microenvironment, including a decreased percentage of tumor-associated macrophages and myeloid-derived suppressor cells, which mediate immune evasion, and an increased percentage of CD8⁺ T cells and natural killer cells, which mediate antitumor immunity. Taken together, these preclinical findings suggest that combining 32-134D with immune checkpoint blockade may represent a breakthrough therapy for HCC.     

Proliferation of human HCC cells and chemically induced mouse liver cancers requires JNK1-dependent p21 downregulation

JNK proteins have been shown to be involved in liver carcinogenesis in mice, but the extent of their involvement in the development of human liver cancers is unknown. Here, we show that activation of JNK1 but not JNK2 was increased in human primary hepatocellular carcinomas (HCCs). Further, JNK1 was required for human HCC cell proliferation in vitro and tumorigenesis after xenotransplantation. Importantly, mice lacking JNK1 displayed decreased tumor cell proliferation in a mouse model of liver carcinogenesis and decreased hepatocyte proliferation in a mouse model of liver regeneration. In both cases, impaired proliferation was caused by increased expression of p21, a cell-cycle inhibitor, and reduced expression of c-Myc, a negative regulator of p21. Genetic inactivation of p21 in JNK1^–/– mice restored hepatocyte proliferation in models of both liver carcinogenesis and liver regeneration, and overexpression of c-Myc increased proliferation of JNK1^–/– liver cells. Similarly, JNK1 was found to control the proliferation of human HCC cells by affecting p21 and c-Myc expression. Pharmacologic inhibition of JNK reduced the growth of both xenografted human HCC cells and chemically induced mouse liver cancers. These findings provide a mechanistic link between JNK activity and liver cell proliferation via p21 and c-Myc and suggest JNK targeting can be considered as a new therapeutic approach for HCC treatment.     

Dysregulated circ_0004913, circ_0008160, circ_0000517, and their potential as biomarkers for disease monitoring and prognosis in hepatocellular carcinoma

ObjectiveCircular RNA_0004913 (circ_0004913), circular RNA_0008160 (circ_0008160), and circular RNA_0000517 (circ_0000517) are shown to be dysregulated in HCC tissues and cell lines, and also show potential in regulating hepatocellular carcinoma (HCC) pathogenesis. This current study attempted to find possible associations of circ_0004913, circ_0008160, and circ_0000517 with clinical features and prognosis of HCC patients.MethodsA hundred and fifty HCC patients who received hepatectomy were retrospectively reviewed, and their resected specimens including tumor tissues and paired adjacent tissues were obtained, in which the circ_0004913, circ_0008160, and circ_0000517 expressions were detected. Overall survival (OS) data were collected according to the clinical visit records.ResultsCirc_0004913 (p < 0.001) and circ_0008160 (p < 0.001) were downregulated, while circ_0000517 (p < 0.001) was upregulated in tumor tissue compared with paired adjacent tissue. Additionally, tumor circ_0004913 was negatively associated with largest tumor size (p = 0.009) and Barcelona clinic liver cancer (BCLC) stage (p = 0.020), while tumor circ_0008160 and circ_0000517 were not correlated with any clinicopathological features of HCC patients (all p > 0.05). Tumor circ_0004913 high expression was associated with prolonged OS in total HCC patients (p = 0.008) and in subgroup of patients with largest tumor size <5 cm (p = 0.008). Tumor circ_0008160 high expression was correlated with longer OS in patients with BCLC stage B (p = 0.026). Univariate Cox''s analysis disclosed that tumor circ_0004913 high expression was correlated with longer OS; while after adjustment by multivariate Cox''s analysis, it failed to predict OS independently.ConclusionCirc_0004913 was downregulated in tumor tissue and may serve as a biomarker for evaluating disease severity and prognosis in HCC patients.     

Macrophage-derived netrin-1 drives adrenergic nerve–associated lung fibrosis

Fibrosis is a macrophage-driven process of uncontrolled extracellular matrix accumulation. Neuronal guidance proteins such as netrin-1 promote inflammatory scarring. We found that macrophage-derived netrin-1 stimulates fibrosis through its neuronal guidance functions. In mice, fibrosis due to inhaled bleomycin engendered netrin-1–expressing macrophages and fibroblasts, remodeled adrenergic nerves, and augmented noradrenaline. Cell-specific knockout mice showed that collagen accumulation, fibrotic histology, and nerve-associated endpoints required netrin-1 of macrophage but not fibroblast origin. Adrenergic denervation; haploinsufficiency of netrin-1’s receptor, deleted in colorectal carcinoma; and therapeutic α₁ adrenoreceptor antagonism improved collagen content and histology. An idiopathic pulmonary fibrosis (IPF) lung microarray data set showed increased netrin-1 expression. IPF lung tissues were enriched for netrin-1⁺ macrophages and noradrenaline. A longitudinal IPF cohort showed improved survival in patients prescribed α₁ adrenoreceptor blockade. This work showed that macrophages stimulate lung fibrosis via netrin-1–driven adrenergic processes and introduced α₁ blockers as a potentially new fibrotic therapy.     

Collapse of the Tumor Stroma is Triggered by IL-12 Induction of Fas

Engineering CD8⁺ T cells to deliver interleukin 12 (IL-12) to the tumor site can lead to striking improvements in the ability of adoptively transferred T cells to induce the regression of established murine cancers. We have recently shown that IL-12 triggers an acute inflammatory environment that reverses dysfunctional antigen presentation by myeloid-derived cells within tumors and leads to an increase in the infiltration of adoptively transferred antigen-specific CD8⁺ T cells. Here, we find that local delivery of IL-12 increased the expression of Fas within tumor-infiltrating macrophages, dendritic cells, and myeloid-derived suppressor cells (MDSC), and that these changes were abrogated in mice deficient in IL-12–receptor signaling. Importantly, upregulation of Fas in host mice played a critical role in the proliferation and antitumor activity of adoptively transferred IL-12–modified CD8⁺ T cells. We also observed higher percentages of myeloid-derived cell populations within tumors in Fas-deficient mice, indicating that tumor stromal destruction was dependent on the Fas death receptor. Taken together, these results describe the likely requirement for costimulatory reverse signaling through Fasl on T cells that successfully infiltrate tumors, a mechanism triggered by the induction of Fas expression on myeloid-derived cells by IL-12 and the subsequent collapse of the tumor stroma.