RhoE/ROCK2 regulates chemoresistance through NF-κB/IL-6/ STAT3 signaling in hepatocellular carcinoma

Synthesis, Docking, and Machine Learning Studies of Some Novel Quinolinesulfonamides-Triazole Hybrids with Anticancer Activity

In the presented work, a series of 22 hybrids of 8-quinolinesulfonamide and 1,4-disubstituted triazole with antiproliferative activity were designed and synthesised. The title compounds were designed using molecular modelling techniques. For this purpose, machine-learning, molecular docking, and molecular dynamics methods were used. Calculations of the pharmacokinetic parameters (connected with absorption, distribution, metabolism, excretion, and toxicity) of the hybrids were also performed. The new compounds were synthesised via a copper-catalysed azide-alkyne cycloaddition reaction (CuAAC). 8-N-Methyl-N-{[1-(7-chloroquinolin-4-yl)-1H-1,2,3-triazol-4-yl]methyl}quinolinesulfonamide was identified in in silico studies as a potential strong inhibitor of Rho-associated protein kinase and as a compound that has an appropriate pharmacokinetic profile. The results obtained from in vitro experiments confirm the cytotoxicity of derivative 9b in four selected cancer cell lines and the lack of cytotoxicity of this derivative towards normal cells. The results obtained from silico and in vitro experiments indicate that the introduction of another quinolinyl fragment into the inhibitor molecule may have a significant impact on increasing the level of cytotoxicity toward cancer cells and indicate a further direction for future research in order to find new substances suitable for clinical applications in cancer treatment.

The Specific ROCK2 Inhibitor KD025 Alleviates Glycolysis through Modulating STAT3-, CSTA- and S1PR3-Linked Signaling in Human Trabecular Meshwork Cells

To investigate the biological significance of Rho-associated coiled-coil-containing protein kinase (ROCK) 2 in the human trabecular meshwork (HTM), changes in both metabolic phenotype and gene expression patterns against a specific ROCK2 inhibitor KD025 were assessed in planar-cultured HTM cells. A seahorse real-time ATP rate assay revealed that administration of KD025 significantly suppressed glycolytic ATP production rate and increased mitochondrial ATP production rate in HTM cells. RNA sequencing analysis revealed that 380 down-regulated and 602 up-regulated differentially expressed genes (DEGs) were identified in HTM cells treated with KD025 compared with those that were untreated. Gene ontology analysis revealed that DEGs were more frequently related to the plasma membrane, extracellular components and integral cellular components among cellular components, and related to signaling receptor binding and activity and protein heterodimerization activity among molecular functions. Ingenuity Pathway Analysis (IPA) revealed that the detected DEGs were associated with basic cellular biological and physiological properties, including cellular movement, development, growth, proliferation, signaling and interaction, all of which are associated with cellular metabolism. Furthermore, the upstream regulator analysis and causal network analysis estimated IL-6, STAT3, CSTA and S1PR3 as possible regulators. Current findings herein indicate that ROCK2 mediates the IL-6/STAT3-, CSTA- and S1PR3-linked signaling related to basic biological activities such as glycolysis in HTM cells.

Loss of RND3/RHOE controls entosis through LAMP1 expression in hepatocellular carcinoma

Entosis is a process that leads to the formation of cell-in-cell structures commonly found in cancers. Here, we identified entosis in hepatocellular carcinoma and the loss of Rnd3 (also known as RhoE) as an efficient inducer of this mechanism. We characterized the different stages and the molecular regulators of entosis induced after Rnd3 silencing. We demonstrated that this process depends on the RhoA/ROCK pathway, but not on E-cadherin. The proteomic profiling of entotic cells allowed us to identify LAMP1 as a protein upregulated by Rnd3 silencing and implicated not only in the degradation final stage of entosis, but also in the full mechanism. Moreover, we found a positive correlation between the presence of entotic cells and the metastatic potential of tumors in human patient samples. Altogether, these data suggest the involvement of entosis in liver tumor progression and highlight a new perspective for entosis analysis in medicine research as a novel therapeutic target.

Recent advances in the development of Rho kinase inhibitors (2015-2021)

Rho-associated coiled-coil kinases (ROCKs) are key downstream effectors of small GTPases. ROCK plays a central role in diverse cellular events with accumulating evidence supporting the concept that ROCK is important in tumor development and progression. Numerous ROCK inhibitors have been investigated for their therapeutic potential in the treatment of cancers. In this article, we review recent research progress on ROCK inhibitors, especially those with potential for the treatment of cancers, reported in the literature from 2015 to 2021. Most ROCK inhibitors show potent in vitro and in vivo antitumor activities and have potential in the treatment of cancers.

Deciphering STAT3 signaling potential in hepatocellular carcinoma: tumorigenesis, treatment resistance, and pharmacological significance

Hepatocellular carcinoma (HCC) is considered one of the greatest challenges to human life and is the most common form of liver cancer. Treatment of HCC depends on chemotherapy, radiotherapy, surgery, and immunotherapy, all of which have their own drawbacks, and patients may develop resistance to these therapies due to the aggressive behavior of HCC cells. New and effective therapies for HCC can be developed by targeting molecular signaling pathways. The expression of signal transducer and activator of transcription 3 (STAT3) in human cancer cells changes, and during cancer progression, the expression tends to increase. After induction of STAT3 signaling by growth factors and cytokines, STAT3 is phosphorylated and translocated to the nucleus to regulate cancer progression. The concept of the current review revolves around the expression and phosphorylation status of STAT3 in HCC, and studies show that the expression of STAT3 is high during the progression of HCC. This review addresses the function of STAT3 as an oncogenic factor in HCC, as STAT3 is able to prevent apoptosis and thus promote the progression of HCC. Moreover, STAT3 regulates both survival- and death-inducing autophagy in HCC and promotes cancer metastasis by inducing the epithelial-mesenchymal transition (EMT). In addition, upregulation of STAT3 is associated with the occurrence of chemoresistance and radioresistance in HCC. Specifically, non-protein-coding transcripts regulate STAT3 signaling in HCC, and their inhibition by antitumor agents may affect tumor progression. In this review, all these topics are discussed in detail to provide further insight into the role of STAT3 in tumorigenesis, treatment resistance, and pharmacological regulation of HCC.

RHO GTPase family in hepatocellular carcinoma

RHO GTPases are a subfamily of the RAS superfamily of proteins, which are highly conserved in eukaryotic species and have important biological functions, including actin cytoskeleton reorganization, cell proliferation, cell polarity, and vesicular transport. Recent studies indicate that RHO GTPases participate in the proliferation, migration, invasion and metastasis of cancer, playing an essential role in the tumorigenesis and progression of hepatocellular carcinoma (HCC). This review first introduces the classification, structure, regulators and functions of RHO GTPases, then dissects its role in HCC, especially in migration and metastasis. Finally, we summarize inhibitors targeting RHO GTPases and highlight the issues that should be addressed to improve the potency of these inhibitors.

Rho Kinase Inhibitor Y27632 Improves Recovery After Spinal Cord Injury by Shifting Astrocyte Phenotype and Morphology via the ROCK/NF-κB/C3 Pathway

Spinal cord injury (SCI) usually results in loss or reduction in motor and sensory functions. Despite extensive research, no available therapy can restore the lost functions after SCI. Reactive astrocytes play a pivotal role in SCI. Rho kinase inhibitors have also been shown to promote functional recovery of SCI. However, the role of Rho kinase inhibitors in reactive astrocytic phenotype switch within SCI remains largely unexplored. In this study, astrocytes were treated with proinflammatory cytokines and/or the Rho kinase inhibitor Y27632. Concomitantly the phenotype and morphology of astrocytes were examined. Meanwhile, the SCI model of SD rats was established, and nerve functions were evaluated following treatment with Y27632. Subsequently, the number of A1 astrocytes in the injured area was observed and analyzed. Eventually, the expression levels of nuclear factor kappa B (NF-κB), C3, and S100A10 were measured. The present study showed that the Rho kinase inhibitor Y27632 improved functional recovery of SCI and elevated the proliferation and migration abilities of the astrocytes. In addition, Y27632 treatment initiated the switch of astrocytes morphology from a flattened shape to a process-bearing shape and transformed the reactive astrocytes A1 phenotype to an A2 phenotype. More importantly, further investigation suggested that Y27632 was actively involved in promoting the functional recovery of SCI in rats by inhabiting the ROCK/NF-κB/C3 signaling pathway. Together, Rho kinase inhibitor Y27632 effectively promotes the functional recovery of SCI by shifting astrocyte phenotype and morphology. Furthermore, the pro-regeneration event is strongly associated with the ROCK/NF-κB/C3 signal pathway.

Mechanical Stretch Promotes Macrophage Polarization and Inflammation via the RhoA-ROCK/NF-κB Pathway

Macrophages play an essential role in the pathogenesis of most inflammatory diseases. Recent studies have shown that mechanical load can influence macrophage function, leading to excessive and uncontrolled inflammation and even systemic damage, including cardiovascular disease and knee osteoarthritis. However, the molecular mechanism remains unclear. In this study, murine RAW264.7 cells were treated with mechanical stretch (MS) using the Flexcell-5000T Tension System. The expression of inflammatory factors and cytokine release were measured by RT-qPCR, ELISA, and Western blotting. The protein expression of NF-κB p65, Iκb-α, p-Iκb-α, RhoA, ROCK1, and ROCK2 was also detected by Western blotting. Then, Flow cytometry was used to detect the proportion of macrophage subsets. Meanwhile, Y-27632 dihydrochloride, a ROCK inhibitor, was added to knockdown ROCK signal transduction in cells. Our results demonstrated that MS upregulated mRNA expression and increased the secretion levels of proinflammatory factors iNOS, IL-1β, TNF-α, and IL-6. Additionally, MS significantly increased the proportion of CD11b+CD86+ and CD11b+CD206+ subsets in RAW264.7 macrophages. Furthermore, the protein expression of RhoA, ROCK1, ROCK2, NF-κB p65, and IκB-α increased in MS-treated RAW264.7 cells, as well as the IL-6 and iNOS. In contrast, ROCK inhibitor significantly blocked the activation of RhoA-ROCK and NF-κB pathway, decreased the protein expression of IL-6 and iNOS, reduced the proportion of CD11b+CD86+ cells subpopulation, and increased the proportion of CD11b+CD206+ cell subpopulation after MS. These data indicate that mechanical stretch can regulate the RAW264.7 macrophage polarization and enhance inflammatory responses in vitro, which may contribute to activation the RhoA-ROCK/NF-κB pathway.

The Crosstalk Between Regulatory Non-Coding RNAs and Nuclear Factor Kappa B in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a highly lethal type of malignancies that possesses great loss of life safety to human beings worldwide. However, few effective means of curing HCC exist and its specific molecular basis is still far from being fully elucidated. Activation of nuclear factor kappa B (NF-κB), which is often observed in HCC, is considered to play a significant part in hepatocarcinogenesis and development. The emergence of regulatory non-coding RNAs (ncRNAs), particularly microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), is a defining advance in cancer biology, and related research in this branch has yielded many diagnostic and therapeutic opportunities. Recent studies have suggested that regulatory ncRNAs act as inhibitors or activators in the initiation and progression of HCC by targeting components of NF-κB signaling or regulating NF-κB activity. In this review, we attach importance to the role and function of regulatory ncRNAs in NF-κB signaling of HCC and NF-κB-associated chemoresistance in HCC, then propose future research directions and challenges of regulatory ncRNAs mediated-regulation of NF-κB pathway in HCC.

RhoGTPase Signalling in Cancer Progression and Dissemination

Rho GTPases are a family of small G proteins that regulate a wide array of cellular processes related to their key roles controlling the cytoskeleton. On the other hand, cancer is a multi-step disease caused by the accumulation of genetic mutations and epigenetic alterations, from the initial stages of cancer development when cells in normal tissues undergo transformation, to the acquisition of invasive and metastatic traits, responsible for a large number of cancer related deaths. In this review, we discuss the role of Rho GTPase signalling in cancer in every step of disease progression. Rho GTPases contribute to tumour initiation and progression, by regulating proliferation and apoptosis, but also metabolism, senescence and cell stemness. Rho GTPases play a major role in cell migration, and in the metastatic process. They are also involved in interactions with the tumour microenvironment and regulate inflammation, contributing to cancer progression. After years of intensive research, we highlight the importance of relevant models in the Rho GTPase field, and we reflect on the therapeutic opportunities arising for cancer patients.

Epidermal ROCK2 induces AKT1/GSK3β/β-catenin, NFκB and dermal tenascin C; but enhanced differentiation and p53/p21 inhibit papilloma

ROCK2 roles in epidermal differentiation and carcinogenesis have been investigated in mice expressing an RU486-inducible, 4HT-activated ROCK2 transgene (K14.creP/lslROCKer). RU486/4HT-mediated ROCKer activation induced epidermal hyperplasia similar to cutaneous oncogenic rasHa (HK1.ras); however ROCKer did not elicit papillomas. Instead, anomalous basal-layer ROCKer expression corrupted normal ROCK2 roles underlying epidermal rigidity/stiffness and barrier maintanance, resulting in premature keratin K1, loricrin and filaggrin expression. Also, hyperproliferative/stress-associated keratin K6 was reduced; possibly reflecting altered ROCK2 roles in epidermal rigidity and keratinocyte flexibility/migration during wound healing. Consistent with increased proliferation, K14.creP/lslROCKer hyperplasia displayed supra-basal-to-basal increases in activated p-AKT1, inactivated p-GSK3β ser9 and membranous/nuclear β-catenin expression together with weak NFκB, which were absent in equivalent HK1.ras hyperplasia. Furthermore, ROCKer-mediated increases in epidermal rigidity via p-MypT1 inactivation/elevated MLC, coupled to anomalous β-catenin expression, induced tenascin C-positive dermal fibroblasts. Alongside an altered ECM, these latent tenascin C-positive dermal fibroblasts may become putative pre-cancer-associated fibroblasts (pre-CAFs) and establish a susceptibility that subsequently contributes to tumour progression. However, anomalous differentiation was also accompanied by an immediate increase in basal-layer p53/p21 expression; suggesting that while ROCK2/AKT1/β-catenin activation increased keratinocyte proliferation resulting in hyperplasia, compensatory p53/p21 and accelerated differentiation helped inhibit papillomatogenesis.

LncRNA PITPNA-AS1 as a Potential Diagnostic Marker and Therapeutic Target Promotes Hepatocellular Carcinoma Progression via Modulating miR-448/ROCK1 Axis

Background: Long non-coding RNAs are critical to hepatocellular carcinoma (HCC) developments. LncRNA PITPNA antisense RNA 1 (PITPNA-AS1) is a new regulator in several tumors. However, the mechanism by which PITPNA-AS1 mediates the tumorigenesis of HCC remains unclear.

Methods: RT-qPCR was used to detect the level of PITPNA-AS1 in HCC specimens and cells. The biological functions of PITPNA-AS1 were explored by several functional experiments in vivo and in vitro. The binding relationship among PITPNA-AS1, miR-448 and ROCK1 were studied by Luciferase assay and pull-down assays.

Results: We found that PITPNA-AS1 expressions were distinctly upregulated in both HCC specimens and cell lines. High PITPNA-AS1 levels were an unfavorable biomarker for patients with HCC. Functionally, knockdown of PITPNA-AS1 suppressed the proliferation, migration and invasion of HCC cells. Mechanistically, PITPNA-AS1 functioned as competing endogenous RNA to increase ROCK1 expressions via sponging miR-448.

Conclusion: The newly identified PITPNA-AS/miR-448/ROCK1 axis promoted the oncogenicity of HCC cells. This novel axis is likely to be a promising HCC therapeutic aim.

GASC1 promotes hepatocellular carcinoma progression by inhibiting the degradation of ROCK2

Hepatocellular carcinoma (HCC) is a devastating malignancy without targeted therapeutic options. Our results indicated that the histone demethylase GASC1 signature is associated with later tumor stage and poorer survival in HCC patients. GASC1 depletion led to diminished HCC proliferation and tumor growth. A distinct heterogeneity in GASC1 levels was observed among HCC cell populations, predicting their inherent high or low tumor-initiating capacity. Mechanistically, GASC1 is involved in the regulation of several components of the Rho-GTPase signaling pathway including its downstream target ROCK2. GASC1 demethylase activity ensured the transcriptional repression of FBXO42, a ROCK2 protein-ubiquitin ligase, thereby inhibiting ROCK2 degradation via K63-linked poly-ubiquitination. Treatment with the GASC1 inhibitor SD70 impaired the growth of both HCC cell lines and xenografts in mice, sensitizing them to standard-of-care chemotherapy. This work identifies GASC1 as a malignant-cell-selective target in HCC, and GASC1-specific therapeutics represent promising candidates for new treatment options to control this malignancy.

Pathophysiological functions of Rnd proteins

Rnd proteins constitute a subfamily of Rho GTPases represented in mammals by Rnd1, Rnd2 and Rnd3. Despite their GTPase structure, their specific feature is the inability to hydrolyse GTP-bound nucleotide. This aspect makes them atypical among Rho GTPases. Rnds are regulated for their expression at the transcriptional or post-transcriptional levels and they are activated through post-translational modifications and interactions with other proteins. Rnd proteins are mainly involved in the regulation of the actin cytoskeleton and cell proliferation. Whereas Rnd3 is ubiquitously expressed, Rnd1 and 2 are tissue-specific. Increasing data has described their important role during development and diseases. Herein, we describe their involvement in physiological and pathological conditions with a focus on the neuronal and vascular systems, and summarize their implications in tumorigenesis.

Ingenuity pathway analysis of differentially expressed genes involved in signaling pathways and molecular networks in RhoE gene‑edited cardiomyocytes

RhoE/Rnd3 is an atypical member of the Rho superfamily of proteins, However, the global biological function profile of this protein remains unsolved. In the present study, a RhoE‑knockout H9C2 cardiomyocyte cell line was established using CRISPR/Cas9 technology, following which differentially expressed genes (DEGs) between the knockout and wild‑type cell lines were screened using whole genome expression gene chips. A total of 829 DEGs, including 417 upregulated and 412 downregulated, were identified using the threshold of fold changes ≥1.2 and P<0.05. Using the ingenuity pathways analysis system with a threshold of ‑Log (P‑value)>2, 67 canonical pathways were found to be enriched. Many of the detected signaling pathways, including that of oncostatin M signaling, were found to be associated with the inflammatory response. Subsequent disease and function analysis indicated that apart from cardiovascular disease and development function, RhoE may also be involved in other diseases and function, including organismal survival, cancer, organismal injury and abnormalities, cell‑to‑cell signaling and interaction, and molecular transport. In addition, 885 upstream regulators were enriched, including 59 molecules that were predicated to be strongly activated (Z‑score >2) and 60 molecules that were predicated to be significantly inhibited (Z‑scores <‑2). In particular, 33 regulatory effects and 25 networks were revealed to be associated with the DEGs. Among them, the most significant regulatory effects were 'adhesion of endothelial cells' and 'recruitment of myeloid cells' and the top network was 'neurological disease', 'hereditary disorder, organismal injury and abnormalities'. In conclusion, the present study successfully edited the RhoE gene in H9C2 cells using CRISPR/Cas9 technology and subsequently analyzed the enriched DEGs along with their associated canonical signaling pathways, diseases and functions classification, upstream regulatory molecules, regulatory effects and interaction networks. The results of the present study should facilitate the discovery of the global biological and functional properties of RhoE and provide new insights into role of RhoE in human diseases, especially those in the cardiovascular system.

Systematic review of the roles of interleukins in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a primary liver cancer with high morbidity and mortality that is often accompanied by immune system disorders and local lymphocyte infiltration. Tumor-infiltrating lymphocytes, cancer cells, stromal cells, and the numerous cytokines they produce, such as chemokines, interferons, tumor necrosis factors, and interleukins, collectively constitute the tumor microenvironment. As a main type of immune effector, interleukin plays opposing roles in regulating tumor cell progression, adhesion, and migration according to its different subtypes. Many reports have concentrated on the roles that interleukins play in HCC, but understanding them systematically remains challenging. This study reviewed the current data to comprehensively summarize the relationships between HCC progression and human interleukin gene families.

RhoC regulates radioresistance via crosstalk of ROCK2 with the DNA repair machinery in cervical cancer

Background

Radioresistance remains a challenge to the successful treatment of various tumors. Intrinsic factors like alterations in signaling pathways regulate response to radiation. RhoC, which has been shown to modulate several tumor phenotypes has been investigated in this report for its role in radioresistance. In vitro and clinical sample-based studies have been performed to understand its contribution to radiation response in cervical cancer and this is the first report to establish the role of RhoC and its effector ROCK2 in cervical cancer radiation response.

Methods

Biochemical, transcriptomic and immunological approaches including flow cytometry and immunofluorescence were used to understand the role of RhoC and ROCK2. RhoC variants, siRNA and chemical inhibitors were used to alter the function of RhoC and ROCK2. Transcriptomic profiling was performed to understand the gene expression pattern of the cells. Live sorting using an intracellular antigen has been developed to isolate the cells for transcriptomic studies.

Results

Enhanced expression of RhoC conferred radioprotection on the tumor cells while inhibition of RhoC resulted in sensitization of cells to radiation. The RhoC overexpressing cells had a better DNA repair machinery as observed using transcriptomic analysis. Similarly, overexpression of ROCK2, protected tumor cells against radiation while its inhibition increased radiosensitivity in vitro. Further investigations revealed that ROCK2 inhibition abolished the radioresistance phenotype, conferred by RhoC on SiHa cells, confirming that it is a downstream effector of RhoC in this context. Additionally, transcriptional analysis of the live sorted ROCK2 high and ROCK2 low expressing SiHa cells revealed an upregulation of the DNA repair pathway proteins. Consequently, inhibition of ROCK2 resulted in reduced expression of pH2Ax and MRN complex proteins, critical to repair of double strand breaks. Clinical sample-based studies also demonstrated that ROCK2 inhibition sensitizes tumor cells to irradiation.

Conclusions

Our data primarily indicates that RhoC and ROCK2 signaling is important for the radioresistance phenotype in cervical cancer tumor cells and is regulated via association of ROCK2 with the proteins of DNA repair pathway involving pH2Ax, MRE11 and RAD50 proteins, partly offering insights into the mechanism of radioresistance in tumor cells. These findings highlight RhoC-ROCK2 signaling involvement in DNA repair and urge the need for development of these molecules as targets to alleviate the non-responsiveness of cervical cancer tumor cells to irradiation treatment.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1385-7) contains supplementary material, which is available to authorized users.

Tumor-associated macrophages modulate resistance to oxaliplatin via inducing autophagy in hepatocellular carcinoma

Background

Oxaliplatin-based chemotherapy is widely used to treat hepatocellular carcinoma (HCC). Recent studies suggested that therapeutic resistance of tumors was affected by tumor microenvironment (TME). As a major component of TME, the role of tumor-associated macrophages (TAMs) on drug resistance in HCC is largely unknown.

Methods

26 HCC samples were obtained from patients who had underwent transarterial chemoembolization (TACE) within 3 months before receiving curative resections. Immunohistochemistry was applied to detect the density of TAMs in these tissues. SMMC-7721 and Huh-7 cell lines were used to co-culture with THP-1 derived macrophages. Under oxaliplatin treatment, cell death was measured using MTT and annexin V/propidium iodide assays. Autophagy activation was evaluated by GFP-LC3 redistribution and LC3 conversion in SMMC-7721 and Huh-7. Short-interfering RNA against ATG5 gene was applied to inhibit autophagy. In vivo validation was conducted in Huh-7 with or without macrophages using an HCC xenograft model in nude mice after oxaliplatin administration.

Results

We found that the density of TAMs in HCC samples was associated with the efficacy of TACE. Macrophages inhibited cell death induced by oxaliplatin in HCC cells. Autophagy was functionally activated in HCC cells after co-culturing with macrophages. Suppression of autophagy using RNA interference of ATG5 in HCC cells promoted the oxaliplatin cytotoxicity in the co-culture system. Critically, co-implantation with macrophages in HCC xenografts weakens cytotoxic effect of oxaliplatin through inducing autophagy to avoid apoptosis.

Conclusions

Our results suggest that TAMs induce autophagy in HCC cells which might contribute to oxaliplatin resistance. Targeting TAMs is a promising therapeutic strategy to enhance the effects of chemotherapy oxaliplatin in HCC patients.

miR-185-5p targets ROCK2 and inhibits cell migration and invasion of hepatocellular carcinoma

Previous studies demonstrated microRNA-185 (miR-185) as a tumor suppressive microRNA (miRNA) in various types of cancer. The current study aimed to verify this finding in hepatocellular carcinoma (HCC) and explored the downstream channel of miR-185-5p. We detected miR-185-5p and Rho-associated coiled-coil containing protein kinase 2 (ROCK2) mRNA and protein levels by reverse transcription-quantitative PCR (RT-qPCR) and western blotting in HCC tissues and cell lines. Luciferase reporter assay proved the direct relationship between miR-185-5p and ROCK2. Cell migration and invasion were assessed via Transwell assay. miR-185-5p level was reduced in HCC tissues and cell lines. miR-185-5p overexpression impeded migration and invasion of HCC cells. Moreover, miR-185-5p directly targeted ROCK2 which was repressed by miR-185-5p in HCC. In addition, ROCK2 contributed to cell metastasis of HCC. In summary, miR-185-5p inhibited cell metastasis of HCC by suppressing ROCK2. The novel miR-185/ROCK2 axis shows potential in improving the therapies of HCC and enhancing HCC survival.

Antrodia camphorata Mycelia Exert Anti-liver Cancer Effects and Inhibit STAT3 Signaling in vitro and in vivo

Hepatocellular carcinoma (HCC), the major form of primary liver cancer, is a common cause of cancer-related death worldwide. Signal transducer and activator of transcription 3 (STAT3) signaling is constantly activated in HCC and has been proposed as a chemotherapeutic target for HCC. Antrodia camphorata (AC), a medicinal mushroom unique to Taiwan, is traditionally used for treating HCC. Whereas natural AC is scarce, cultured AC mycelia are becoming alternatives. In this study, we investigated the anti-HCC effects of the ethyl acetate fraction of an ethanolic extract of AC mycelia (EEAC), particularly exploring the involvement of STAT3 signaling in these effects. We found that EEAC reduced cell viability, induced apoptosis, and retarded migration and invasion in cultured HepG2 and SMMC-7721 cells. Immunoblotting results showed that EEAC downregulated protein levels of phosphorylated and total STAT3 and JAK2 (an upstream kinase of STAT3) in HCC cells. Real-time PCR analyses showed that STAT3, but not JAK2, mRNA levels were decreased by EEAC. EEAC also lowered the protein level of nuclear STAT3, decreased the transcriptional activity of STAT3, and downregulated protein levels of STAT3-targeted molecules, including anti-apoptotic proteins Bcl-xL and Bcl-2, and invasion-related proteins MMP-2 and MMP-9. Over-activation of STAT3 in HCC cells diminished the cytotoxic effects of EEAC. In SMMC-7721 cell-bearing mice, EEAC (100 mg/kg, i.g. for 18 days) significantly inhibited tumor growth. Consistent with our in vitro data, EEAC induced apoptosis and suppressed JAK2/STAT3 activation/phosphorylation in the tumors. Taken together, EEAC exerts anti-HCC effects both in vitro and in vivo; and inhibition of STAT3 signaling is, at least in part, responsible for these effects. We did not observe significant toxicity of EEAC in normal human liver-derived cells, nude mice and rats. Our results provide a pharmacological basis for developing EEAC as a safe and effective agent for HCC management.

α7nAChR-mediated recruitment of PP1γ promotes TRAF6/NF-κB cascade to facilitate the progression of Hepatocellular Carcinoma

The cholinergic signaling pathways have been recently implicated in the development of various human cancers. However, the underlying molecular mechanism remains largely unclear. In the present study, we reported that α7 nicotinic acetylcholine receptor (α7nAChR), an important member of nicotinic acetylcholine receptors, interacts with Protein Phosphatase-1γ (PP1γ) in human Hepatocellular Carcinoma (HCC) tissues. In addition, we found that α7nAChR facilitates the ubiquitination and activation of TRAF6 in a PP1γ-dependent manner in HCC cells. Furthermore, we showed that ligand-bounded α7nAChR induces the degradation of IκBα, leading to resultant phosphorylation and nuclear accumulation of NF-κB p65. Accordingly, acetylcholine triggers the expression of critical NF-κB target genes, such as Cyclin D1 and PCNA, as well as the proliferation of HCC cells in a PP1γ- and α7nAChR-dependent manner. Furthermore, we revealed that nicotine-triggered α7nAChR activation promotes oncosphere formation and in vivo tumor growth of HCC cells. Moreover, we showed that the protein levels of both α7nAChR and PP1γ are significantly upregulated in human HCC specimens compared with adjacent non-cancerous ones, and that upregulated expression of the two proteins predict significantly worsened prognosis in HCC patients. These findings together indicate that the cholinergic receptor α7nAChR exerts a facilitating role in HCC development through PP1γ-dependent TRAF6/NF-κB signaling.

Inhibition of microRNA-16 facilitates the paclitaxel resistance by targeting IKBKB via NF-κB signaling pathway in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumor usually resistant to chemotherapy. MicroRNAs play important roles in modulation of carcinogenesis and chemoresistance, which miR-16 has been reported to mediate chemoresistance in many types of cancers. However, the role of miR-16 in HCC remains unknown. The aim of this study was to investigate whether miR-16 is participated in chemoresistance in HCC and shed light on the underlying molecular mechanisms. The findings of the current study discover that miR-16 is down-regulated in HCC tissue and cell lines. The results demonstrate that the inhibition of miR-16 renders resistance to paclitaxel in vitro and in vivo by targeting IKBKB via NF-κB signaling pathway, suggesting that miR-16 may be a meaningful therapeutic potential to overcome drug resistance in HCC.

Embelin inhibits abdominal aortic aneurysm through decreasing IL‑6‑induced STAT3 and NF‑κB inactivation

The aim of the present study was to investigate the effect of embelin on abdominal aortic aneurysm (AAA). AAA model mice were induced by chronic infusion of 1,000 ng/kg/min Angiotensin II. AAA model mice were treated with 25, 50 or 100 mg/kg embelin for 28 days. Embelin inhibited tumor necrosis factor‑α, interleukin (IL)‑1β, IL‑6, IL‑18 and malondialdehyde (MDA) level activities, increased superoxide dismutase, glutathione (GSH) and GSH peroxidase level activities and inhibited MDA level activities in AAA mice Embelin suppressed the secretion of matrix metalloproteinase‑9 protein expression, monocyte chemoattractant protein‑2 activity and epithelial neutrophil‑activating peptide expression levels in AAA mice. Embelin suppressed phosphorylated‑signal transducer and activator of transcription (STAT) 3, phosphorylated‑p38 mitogen‑activated protein kinase and nuclear factor (NF)‑κB protein expression in AAA mice. These findings indicate that embelin inhibits AAA through decreasing IL‑6‑induced STAT3, and NF‑κB inactivation.

Retracted Article: MiR-182-5p and miR-96-5p increased hepatocellular carcinoma cell mobility, proliferation and cisplatin resistance partially by targeting RND3

We investigated whether miR-182-5p or miR-96-5p could increase hepatocellular carcinoma (HCC) development by targeting Rho Family GTPase 3 (RND3) gene expression. The expression levels of miR-182-5p, miR-96-5p and mRNA/protein of RND3 in non-HCC liver tissue, HCC tissue and adjacent tissue specimens were evaluated by RT-qPCR and western blot. Patient-derived HCC cell culture was established, and miR-182-5p or miR-96-5p agomir or antagomir treatment was performed to mimic the overexpression or knockdown of the two miRNAs. HCC cell mobility in vitro was monitored by trans-well migration and invasion assay, while HCC cell growth in vitro was evaluated by cell viability, proliferation and apoptosis assay. HCC cell apoptosis was further investigated by caspase-3/-8/-9 activity assay. MiR-182-5p and miR-96-5p were significantly upregulated in HCC tissue specimens compared with non-HCC or adjacent tissue specimens, inversely correlating to RND3 mRNA expression level. Treatment with miR-182-5p or miR-96-5p agomir significantly reduced RND3 mRNA/protein expression level in HCC cells. MiR-182-5p- or miR-96-5p-targeting RND3 mRNA was verified by luciferase reporter assay and AGO2-RNA immunoprecipitation assay. MiR-182-5p or miR-96-5p agomir treatment significantly rescued HCC cell migration and invasion in vitro that were repressed by RND3 overexpression, during which ROCK1 and ROCK2 inhibition were involved. MiR-182-5p or miR-96-5p agomir treatment also increased HCC cell proliferation and cisplatin resistance in vitro, which could be antagonized by RND3 overexpression or ROCK inhibition. Thus, miR-182-5p and miR-96-5p increased HCC cell mobility, proliferation and cisplatin resistance in vitro partially by targeting RND3.

We investigated whether miR-182-5p or miR-96-5p could increase hepatocellular carcinoma (HCC) development by targeting Rho Family GTPase 3 (RND3) gene expression.

NBPF7 promotes the proliferation of α-catenin-knockdown HaCaT cells via functional interaction with the NF-κB pathway

Loss of key components that form cell-cell adherens junctions, such as α-catenin, triggers severe epidermal hyperproliferation. However, the underlying molecular mechanisms remain largely unknown. We report here that neuroblastoma breakpoint family (NBPF) genes are upregulated and that NBPF7 specifically promotes cellular proliferation of α-catenin-silenced HaCaT cells through functional linkage with the NF-κB pathway. Genome-wide profiling of HaCaT cells shows that NBPF genes are upregulated following α-catenin knockdown. Data from western blot analyses are consistent with the activation of the NF-κB pathway as well as increased expression of NBPF7 by α-catenin knockdown. Co-immunoprecipitation assays indicate that NBPF7 could be detected in endogenous activated NF-κB immunoprecipitates. Immunoflurence analyses demonstrate that NBPF7 co-localizes with activated NF-κB in the nucleus after α-catenin silencing. Moreover, inhibition of NBPF7 decreases the proliferation of HaCaT cells and abolishes the enhanced proliferation associated with α-catenin knockdown in HaCaT cells. These results indicate that NBPF7 plays a key role in the α-catenin signaling pathway that regulates cell proliferation of keratinocytes. Our findings suggest that the classical NF-κB pathway plays a critical role in cellular proliferation and that NBPF7 is a functional mediator for α-catenin in the regulation of keratinocyte growth.

Peri-tumor associated fibroblasts promote intrahepatic metastasis of hepatocellular carcinoma by recruiting cancer stem cells

Fibroblasts have been reported to play an important role in hepatocellular carcinoma (HCC). However, the role of fibroblasts have not been fully understood. Conditioned medium collected from human peri-tumor tissue-derived fibroblasts (CM-pTAFs) showed high metastasis ability than human HCC tissues-derived fibroblasts (CM-TAFs). To determine what component was secreted from fibroblasts, we used Bio-Plex analysis system and compared the factors secreted from CM-pTAFs and CM-TAFs, found a series of up-regulated cytokines in the CM-pTAFs, including IL-6, CCL2, CXCL1, CXCL8, SCGF-β, HGF and VEGF. Pretreatment of IL-6 inhibitor Tocilizumab could inhibit metastasis the HCC cell treated with CM-pTAFs in vitro and in vivo. The expression of CCR2 and CXCR1 were up-regulated after CM-pTAFs treatment in HCC cell line SMMC-7721. Flow cytometric analysis experiment showed that most CCR2 or CXCR1 positive cells were also EpCAM positive. In vitro studies also showed that CM-pTAFs could increase stemness of SMMC-7721. In addition, neutralization of SCGF-β and HGF could significantly reduce metastasis and viability of cancer stem cells treated with CM-pTAFs. Taken together, these results indicated that the peri-tumor tissues derived fibroblasts may promote development of HCC by recruiting cancer stem cells and maintaining their stemness characteristic.

Hepatic inflammation-fibrosis-cancer axis in the rat hepatocellular carcinoma induced by diethylnitrosamine

PURPOSE

Hepatocellular carcinoma (HCC) cases are closely associated with chronic inflammation and fibrosis which is known as hepatic inflammation-fibrosis-cancer (IFC) axis. The aim of this study is to elucidate the development characteristics of the rat HCC model based on IFC axis.

METHODS

The diethylnitrosamine (DEN)-induced rat HCC, which presents a stepwise histopathological progression that is similar to human HCC, was used to analyze the features of the different stages (inflammation, fibrosis, cancer). Rats were injected DEN at a dose of 30 mg/kg body weight twice a week for 11 weeks and the animals were observed until week 20. Time series sera and organ samples from the DEN animal model were collected to evaluate the dynamic changes.

RESULTS

It was found that serum biochemical indicators (AST, ALT, ALP, TP, T-BIL, IL-6, TNF-α) from DEN-treated group were higher than that from control group. Fibrosis-related index in serum and live tissue were increased, respectively, from week 4 after DEN treatment. The expression of TGF-β1 and α-SMA in DEN-treated group was higher than that in control group. JAK2/STAT3 signaling was significantly up-regulated in DEN-treated group compared to that in control group. The histological examination confirmed that the hepatocarcinogenesis model was successfully established, and 100% of the animals in the DEN-exposed group developed liver tumors at 20 weeks. According to the pathological changes, the model characterized resulted in three stages: the inflammation stage (week 2-6), the fibrosis stage (week 8-12), and the HCC stage (week 14-20).

CONCLUSIONS

The results suggested that the HCC development was associated with IFC axis. The serial progression of hepatocarcinogenesis was according to the sequence of hepatic inflammation, fibrosis and then hepatic tumor.

Protein Regulator of Cytokinesis PRC1 Confers Chemoresistance and Predicts an Unfavorable Postoperative Survival of Hepatocellular Carcinoma Patients

Background: PRC1, a microtubules(MTs)-associated protein, is essential in the mitosis and cell cycle regulation. It has been recently linked to chemoresistance and tumorigenesis. The current study sought to explore the role of PRC1 on chemoresistance and postoperative prognosis of hepatocellular carcinoma(HCC). Methods: PRC1 was transfected into HCC cells to detect its effects of chemoresistance to 5-fluorouracil in vitro and in vivo. This study also investigated the impact of PRC1 on 5-FU-induced G2/M phase arrest and the potential molecular mechanism. Surgical specimens from HCC patients were examined immunohistochemically for PRC1 expression. Results: Ectopic expression of PRC1 significantly increased the chemoresistance, promoted the tumor growth and abrogated 5-FU-induced G2/M phase arrest via p21/p27-pRBs pathway. In clinical specimens, high expression of PRC1(immunostaining score≥3) in HCC cells predicted an unfavorable postoperative survival of HCC patients(P=0.019), especially for whom received postoperative chemotherapy(P=0.002). In multivariate Cox analyses, high PRC1 expression significantly predicted an unfavorable postoperative prognosis, not dependent of TNM stage. Conclusion: High PRC1 expression in HCC cells increased chemoresistance, attenuated 5-FU-induced apoptosis, abrogated 5-FU-induced G2/M phase arrest, and predicts an unfavorable survival, especially for the patients who received chemotherapy. PRC1 might be a novel prognostic and predictive marker and therapeutic target for HCC patients.