Rho-associated kinases in tumorigenesis: re-considering ROCK inhibition for cancer therapy

Harnessing the synergistic potential of NK1R antagonists and selective COX-2 inhibitors for simultaneous targeting of TNBC cells and cancer stem cells

Triple-negative breast cancer (TNBC) lacks the expression of oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), rendering it unresponsive to endocrine therapy and HER2 targeted treatments. Though certain chemotherapeutics targeting the cell cycle have shown efficacy to a certain extent, the presence of chemotherapy-resistant cancer stem cells (CSCs) presents a significant challenge in tackling TNBC. Multiple lines of evidence suggest the upregulation of neuropeptide Substance P (SP), its NK-1 receptor (NK1R) and the Cyclooxygenase-2 (COX-2) enzyme in TNBC patients. Upregulation of the SP/NK1R system and COX-2 influences major signalling pathways involved in cell proliferation, growth, survival, angiogenesis, inflammation, metastasis and stem cell activity. The simultaneous activation and crosstalk between the pathways activated by SP/NK1R and COX-2 consequently increase the levels of key regulators of self-renewal pathways in CSCs, promoting stemness. The combination therapy with NK1R antagonists and COX-2 inhibitors can simultaneously target TNBC cells and CSCs, thereby enhancing treatment efficacy and reducing the risk of recurrence and relapse. This review discusses the rationale for combining NK1R antagonists and COX-2 inhibitors for the better management of TNBC and a novel strategy to deliver drug cargo precisely to the tumour site to address the challenges associated with off-target binding.

miRNA-mediated inhibition of an actomyosin network in hippocampal pyramidal neurons restricts sociability in adult male mice

Social deficits are frequently observed in patients suffering from neurodevelopmental disorders, but the molecular mechanisms regulating sociability are still poorly understood. We recently reported that the loss of the microRNA (miRNA) cluster miR-379-410 leads to hypersocial behavior and anxiety in mice. Here, we show that ablating miR-379-410 in excitatory neurons of the postnatal mouse hippocampus recapitulates hypersociability, but not anxiety. At the cellular level, miR-379-410 loss in excitatory neurons leads to larger dendritic spines, increased excitatory synaptic transmission, and upregulation of an actomyosin gene network. Re-expression of three cluster miRNAs, as well as pharmacological inhibition of the actomyosin activator ROCK, is sufficient to reinstate normal sociability in miR-379-410 knockout mice. Several actomyosin genes and miR-379-410 family members are reciprocally dysregulated in isogenic human induced pluripotent stem cell (iPSC)-derived neurons harboring a deletion present in patients with Williams-Beuren syndrome, characterized by hypersocial behavior. Together, our results show an miRNA-actomyosin pathway involved in social behavior regulation.

Rho-Associated Protein Kinase Activity Is Required for Tissue Homeostasis in the Xenopus laevis Ciliated Epithelium

Lung epithelial development relies on the proper balance of cell proliferation and differentiation to maintain homeostasis. When this balance is disturbed, it can lead to diseases like cancer, where cells undergo hyperproliferation and then can undergo migration and metastasis. Lung cancer is one of the deadliest cancers, and even though there are a variety of therapeutic approaches, there are cases where treatment remains elusive. The rho-associated protein kinase (ROCK) has been thought to be an ideal molecular target due to its role in activating oncogenic signaling pathways. However, in a variety of cases, inhibition of ROCK has been shown to have the opposite outcome. Here, we show that ROCK inhibition with y-27632 causes abnormal epithelial tissue development in Xenopus laevis embryonic skin, which is an ideal model for studying lung cancer development. We found that treatment with y-27632 caused an increase in proliferation and the formation of ciliated epithelial outgrowths along the tail edge. Our results suggest that, in certain cases, ROCK inhibition can disturb tissue homeostasis. We anticipate that these findings could provide insight into possible mechanisms to overcome instances when ROCK inhibition results in heightened proliferation. Also, these findings are significant because y-27632 is a common pharmacological inhibitor used to study ROCK signaling, so it is important to know that in certain in vivo developmental models and conditions, this treatment can enhance proliferation rather than lead to cell cycle suppression.

LINC00645 inhibits renal cell carcinoma progression by interacting with HNRNPA2B1 to regulate the ROCK1 mRNA stability

The lncRNA plays an important role in tumorigenesis and the progression of renal cell carcinoma (RCC). LINC00645 is one of the most different expressed lncRNA between RCC and normal renal tissue. However, the regulatory mechanism of LINC00645 in RCC remains unknown. Our results indicated that LINC00645 inhibited RCC proliferation, migration, and invasion. Mechanistically, HNRNPA2B1 directly bound to ROCK1 mRNA and strengthened its stability. LINC00645 competitively bound to the RRM1 domain, which is responsible for interacting with ROCK1 mRNA, reducing ROCK1 mRNA level by affecting posttranscriptional destabilization. The expression of LINC00645 was significantly reduced in RCC cells, significantly upregulating ROCK1 by abolishing the interaction with HNRNPA2B1, finally promoting RCC proliferation, migration, and invasion. Moreover, RCC cells with lower LINC00645 expression were more sensitive to the ROCK1 inhibitor Y-27632. Our study indicates that decreased expression of LINC00645 promotes the RCC progression via HNRNPA2B1/ROCK1 axis, providing a promising treatment strategy for RCC patients with decreased LINC00645 expression.

ROCK1/2 signaling contributes to corticosteroid-refractory acute graft-versus-host disease

Patients with corticosteroid-refractory acute graft-versus-host disease (aGVHD) have a low one-year survival rate. Identification and validation of novel targetable kinases in patients who experience corticosteroid-refractory-aGVHD may help improve outcomes. Kinase-specific proteomics of leukocytes from patients with corticosteroid-refractory-GVHD identified rho kinase type 1 (ROCK1) as the most significantly upregulated kinase. ROCK1/2 inhibition improved survival and histological GVHD severity in mice and was synergistic with JAK1/2 inhibition, without compromising graft-versus-leukemia-effects. ROCK1/2-inhibition in macrophages or dendritic cells prior to transfer reduced GVHD severity. Mechanistically, ROCK1/2 inhibition or ROCK1 knockdown interfered with CD80, CD86, MHC-II expression and IL-6, IL-1β, iNOS and TNF production in myeloid cells. This was accompanied by impaired T cell activation by dendritic cells and inhibition of cytoskeletal rearrangements, thereby reducing macrophage and DC migration. NF-κB signaling was reduced in myeloid cells following ROCK1/2 inhibition. In conclusion, ROCK1/2 inhibition interferes with immune activation at multiple levels and reduces acute GVHD while maintaining GVL-effects, including in corticosteroid-refractory settings.

Hepatocellular Carcinoma: Up-regulated Circular RNAs Which Mediate Efficacy in Preclinical In Vivo Models

Hepatocellular carcinoma (HCC) ranges as number two with respect to the incidence of tumors and is associated with a dismal prognosis. The therapeutic efficacy of approved multi-tyrosine kinase inhibitors and checkpoint inhibitors is modest. Therefore, the identification of new therapeutic targets and entities is of paramount importance. We searched the literature for up-regulated circular RNAs (circRNAs) which mediate efficacy in preclinical in vivo models of HCC. Our search resulted in 14 circRNAs which up-regulate plasma membrane transmembrane receptors, while 5 circRNAs induced secreted proteins. Two circRNAs facilitated replication of Hepatitis B or C viruses. Three circRNAs up-regulated high mobility group proteins. Six circRNAs regulated components of the ubiquitin system. Seven circRNAs induced GTPases of the family of ras-associated binding proteins (RABs). Three circRNAs induced redox-related proteins, eight of them up-regulated metabolic enzymes and nine circRNAs induced signaling-related proteins. The identified circRNAs up-regulate the corresponding targets by sponging microRNAs. Identified circRNAs and their targets have to be validated by standard criteria of preclinical drug development. Identified targets can potentially be inhibited by small molecules or antibody-based moieties and circRNAs can be inhibited by small-interfering RNAs (siRNAs) or short hairpin RNAs (shRNAs) for therapeutic purposes.

Ez-Metastasizing: The Crucial Roles of Ezrin in Metastasis

Ezrin is the cytoskeletal organizer and functions in the modulation of membrane-cytoskeleton interaction, maintenance of cell shape and structure, and regulation of cell-cell adhesion and movement, as well as cell survival. Ezrin plays a critical role in regulating tumor metastasis through interaction with other binding proteins. Notably, Ezrin has been reported to interact with immune cells, allowing tumor cells to escape immune attack in metastasis. Here, we review the main functions of Ezrin, the mechanisms through which it acts, its role in tumor metastasis, and its potential as a therapeutic target.

Nanomaterials in tumor immunotherapy: new strategies and challenges

Tumor immunotherapy exerts its anti-tumor effects by stimulating and enhancing immune responses of the body. It has become another important modality of anti-tumor therapy with significant clinical efficacy and advantages compared to chemotherapy, radiotherapy and targeted therapy. Although various kinds of tumor immunotherapeutic drugs have emerged, the challenges faced in the delivery of these drugs, such as poor tumor permeability and low tumor cell uptake rate, had prevented their widespread application. Recently, nanomaterials had emerged as a means for treatment of different diseases due to their targeting properties, biocompatibility and functionalities. Moreover, nanomaterials possess various characteristics that overcome the defects of traditional tumor immunotherapy, such as large drug loading capacity, precise tumor targeting and easy modification, thus leading to their wide application in tumor immunotherapy. There are two main classes of novel nanoparticles mentioned in this review: organic (polymeric nanomaterials, liposomes and lipid nanoparticles) and inorganic (non-metallic nanomaterials and metallic nanomaterials). Besides, the fabrication method for nanoparticles, Nanoemulsions, was also introduced. In summary, this review article mainly discussed the research progress of tumor immunotherapy based on nanomaterials in the past few years and offers a theoretical basis for exploring novel tumor immunotherapy strategies in the future.

Phthalazinone-based lactams and cyclic ureas as ROCK2 selective inhibitors

Derivatives of lactam, cyclic urea and carbamate were explored as aniline amide replacements in a series of phthalazinone-based ROCK inhibitors. Potent ROCK2 inhibitors such as 22 were identified with excellent overall kinase selectivity as well as good isoform selectivity over ROCK1.

Application and Study of ROCK Inhibitors in Pulmonary Fibrosis: Recent Developments and Future Perspectives

Rho-associated coiled-coil-containing kinases (ROCKs), serine/threonine protein kinases, were initially identified as downstream targets of the small GTP-binding protein Rho. Pulmonary fibrosis (PF) is a lethal disease with limited therapeutic options and a particularly poor prognosis. Interestingly, ROCK activation has been demonstrated in PF patients and in animal PF models, making it a promising target for PF treatment. Many ROCK inhibitors have been discovered, and four of these have been approved for clinical use; however, no ROCK inhibitors are approved for the treatment of PF patients. In this article, we describe ROCK signaling pathways and the structure-activity relationship, potency, selectivity, binding modes, pharmacokinetics (PKs), biological functions, and recently reported inhibitors of ROCKs in the context of PF. We will also focus our attention on the challenges to be addressed when targeting ROCKs and discuss the strategy of ROCK inhibitor use in the treatment of PF.

Up-regulated Circular RNAs in Colorectal Cancer: New Entities for Therapy and Tools for Identification of Therapeutic Targets

Patients with disseminated colorectal cancer have a dismal prognosis with a 5-year survival rate of only 13%. In order to identify new treatment modalities and new targets, we searched the literature for up-regulated circular RNAs in colorectal cancer which induce tumor growth in corresponding preclinical in vivo models. We identified nine circular RNAs that mediate resistance against chemotherapeutic agents, seven that up-regulate transmembrane receptors, five that induce secreted factors, nine that activate signaling components, five which up-regulate enzymes, six which activate actin-related proteins, six which induce transcription factors and two which up-regulate the MUSASHI family of RNA binding proteins. All of the circular RNAs discussed in this paper induce the corresponding targets by sponging microRNAs (miRs) and can be inhibited by RNAi or shRNA in vitro and in xenograft models. We have focused on circular RNAs with demonstrated activity in preclinical in vivo models because the latter is an important milestone in drug development. All circular RNAs with in vitro activity only data are not referenced in this review. The translational impact of inhibition of these circular RNAs and of the identified targets for treatment of colorectal cancer (CRC) are discussed.

LncRNA IUR Is Downregulated in Gastric Carcinoma and Associated with Poor Survival

Objective: LncRNA IUR has been recently identified as a key regulator of Bcr-Abl-induced tumorigenesis, while its role in gastric carcinoma (GC) is unknown. This study investigated the involvement of IUR in GC. Materials and Methods: Gene expression levels were measured by performing quantitative polymerase chain reaction. Interactions between IUR and ROCK1 were analyzed by transfection experiments. Cell invasion and migration were analyzed by Transwell assay. Results: In this study, the authors showed that IUR was downregulated in GC. A follow-up study showed that low IUR expression levels predicted poor survival. In GC tissues, ROCK1 was upregulated in GC tissues and inversely correlated with IUR. In GC cells, IUR overexpression mediated the downregulation of ROCK1. ROCK1 overexpression resulted in increased GC cell invasion and migration, while IUR overexpression played an opposite role. Conclusion: IUR is downregulated in GC and inhibits GC cell invasion and migration by downregulating ROCK1.

Preclinical to clinical utility of ROCK inhibitors in cancer

ROCK belongs to the AGC family of Ser/Thr protein kinases that are involved in many cellular processes. ROCK-driven actomyosin contractility regulates cytoskeletal dynamics underpinning cell migration, proliferation, and survival in many cancer types. ROCK1/2 play key protumorigenic roles in several subtypes and stages of cancer development. Therefore, successfully targeting ROCK and its downstream effectors presents an interesting avenue for cancer treatment. Because local use of ROCK inhibitors will reduce the side effects of systemic administration, we propose different therapeutic strategies and latest-generation ROCK inhibitors for use in the clinic.

Dasabuvir suppresses esophageal squamous cell carcinoma growth in vitro and in vivo through targeting ROCK1

Esophageal squamous cell carcinoma (ESCC) is an upper gastrointestinal cancer with high morbidity and mortality. New strategies are urgently needed to prolong patients' survival. Through screening FDA-approved drugs, we found dasabuvir, a drug approved for hepatitis C virus (HCV) treatment, suppressed ESCC proliferation. Dasabuvir could inhibit the growth of ESCC cells in a time and dose-dependent manner and arrested cell cycle at the G0/G1 phase. The antitumor activity was further validated in vivo using patient-derived xenograft tumor models. In terms of mechanism, we unveil that dasabuvir is a Rho-associated protein kinase 1 (ROCK1) inhibitor. Dasabuvir can bind to ROCK1 and suppress its kinase activity, thus downregulating the phosphorylation of ERK1/2 by ROCK1 and the expression of cyclin-dependent kinase 4 (CDK4) and cyclin D1. These results provide evidence that dasabuvir suppresses ESCC growth in vivo and in vitro through blocking ROCK1/ERK signaling pathway.

Opportunities and Challenges for the Development of MRCK Kinases Inhibitors as Potential Cancer Chemotherapeutics

Cytoskeleton organization and dynamics are rapidly regulated by post-translational modifications of key target proteins. Acting downstream of the Cdc42 GTPase, the myotonic dystrophy-related Cdc42-binding kinases MRCKα, MRCKβ, and MRCKγ have recently emerged as important players in cytoskeleton regulation through the phosphorylation of proteins such as the regulatory myosin light chain proteins. Compared with the closely related Rho-associated coiled-coil kinases 1 and 2 (ROCK1 and ROCK2), the contributions of the MRCK kinases are less well characterized, one reason for this being that the discovery of potent and selective MRCK pharmacological inhibitors occurred many years after the discovery of ROCK inhibitors. The disclosure of inhibitors, such as BDP5290 and BDP9066, that have marked selectivity for MRCK over ROCK, as well as the dual ROCK + MRCK inhibitor DJ4, has expanded the repertoire of chemical biology tools to study MRCK function in normal and pathological conditions. Recent research has used these novel inhibitors to establish the role of MRCK signalling in epithelial polarization, phagocytosis, cytoskeleton organization, cell motility, and cancer cell invasiveness. Furthermore, pharmacological MRCK inhibition has been shown to elicit therapeutically beneficial effects in cell-based and in vivo studies of glioma, skin, and ovarian cancers.

Stroma-targeting strategies in pancreatic cancer: a double-edged sword

Pancreatic ductal adenocarcinoma (PDAC) is a type of cancer with limited treatment options and terrible long-term survival, and it is expected to become the second leading cause of cancer-related death by 2030. One reason why this cancer is so aggressive and resistant is the formation of dense stroma that surrounds the neoplastic epithelium, which promotes tumor progression, invasion, metastasis, and resistance. The three major components of PDAC stroma are extracellular matrix (ECM), cancer-associated fibroblasts (CAFs), and vasculature. The dense ECM acts as a natural physical barrier, impeding drug penetration to PDAC tumor cells. Consequently, the method that combines stroma-targeting with anticancer therapy may be a viable alternative for increasing drug penetration. Additionally, blood vessels are key entities of the tumor stroma, serving as a pathway for nutrition as well as the only way for chemical medicines and immune cells to act. Finally, PDAC CAFs and tumor cells have crosstalk effects in the tumor microenvironment, where they are responsible for enhanced matrix deposition. In this review, we aim to provide an overview of our current comprehension of the three key components of PDAC stroma and the new promising therapeutic targets for PDAC.

RHOA Therapeutic Targeting in Hematological Cancers

Primarily identified as an important regulator of cytoskeletal dynamics, the small GTPase Ras homolog gene family member A (RHOA) has been implicated in the transduction of signals regulating a broad range of cellular functions such as cell survival, migration, adhesion and proliferation. Deregulated activity of RHOA has been linked to the growth, progression and metastasis of various cancer types. Recent cancer genome-wide sequencing studies have unveiled both RHOA gain and loss-of-function mutations in primary leukemia/lymphoma, suggesting that this GTPase may exert tumor-promoting or tumor-suppressive functions depending on the cellular context. Based on these observations, RHOA signaling represents an attractive therapeutic target for the development of selective anticancer strategies. In this review, we will summarize the molecular mechanisms underlying RHOA GTPase functions in immune regulation and in the development of hematological neoplasms and will discuss the current strategies aimed at modulating RHOA functions in these diseases.

Amoeboid migration in health and disease: Immune responses versus cancer dissemination

Cell migration is crucial for efficient immune responses and is aberrantly used by cancer cells during metastatic dissemination. Amoeboid migrating cells use myosin II-powered blebs to propel themselves, and change morphology and direction. Immune cells use amoeboid strategies to respond rapidly to infection or tissue damage, which require quick passage through several barriers, including blood, lymph and interstitial tissues, with complex and varied environments. Amoeboid migration is also used by metastatic cancer cells to aid their migration, dissemination and survival, whereby key mechanisms are hijacked from professionally motile immune cells. We explore important parallels observed between amoeboid immune and cancer cells. We also consider key distinctions that separate the lifespan, state and fate of these cell types as they migrate and/or fulfil their function. Finally, we reflect on unexplored areas of research that would enhance our understanding of how tumour cells use immune cell strategies during metastasis, and how to target these processes.

Preclinical evaluation of the ROCK1 inhibitor, GSK269962A, in acute myeloid leukemia

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy with high mortality that urgently requires new treatments. ROCK1 plays an essential role in regulating growth and survival in AML cells. In this study, we evaluated GSK269962A, a selective ROCK1 inhibitor, in preclinical models of AML. Compared with solid tumors, GSK269962A selectively inhibited cell growth and clonogenicity of AML cells. Furthermore, GSK269962A arrested AML cells in the G2 phase and induced apoptosis by regulating multiple cell cycle- and apoptosis-associated proteins. Strikingly, GSK269962A could eliminate leukemia cells from bone marrow, liver, and spleen in an animal model of AML and significantly prolong mouse survival. Mechanistically, GSK269962A could inhibit the growth of AML by blocking ROCK1/c-Raf/ERK signaling pathway. Notably, a correlation was found between the expression levels of ROCK1 protein and the sensitivity of GSK269962A in AML. These data highlight the potential role of ROCK1 as an attractive target for treating AML, as well as the potential of GSK269962A for use in clinical trials of AML.

Immunogenic Death of Hepatocellular Carcinoma Cells in Mice Expressing Caspase-Resistant ROCK1 Is Not Replicated by ROCK Inhibitors

The morphological changes during apoptosis help facilitate "immunologically silent" cell death. Caspase cleavage of the ROCK1 kinase results in its activation, which drives the forceful contraction of apoptotic cells. We previously showed that when ROCK1 was mutated to render it caspase-resistant, there was greater liver damage and neutrophil recruitment after treatment with the hepatotoxin diethylnitrosamine (DEN). We now show that acute DEN-induced liver damage induced higher levels of pro-inflammatory cytokines/chemokines, indicative of immunogenic cell death (ICD), in mice expressing non-cleavable ROCK1 (ROCK1nc). Hepatocellular carcinoma (HCC) tumours in ROCK1nc mice had more neutrophils and CD8⁺ T cells relative to mice expressing wild-type ROCK1, indicating that spontaneous tumour cell death also was more immunogenic. Since ICD induction has been proposed to be tumour-suppressive, the effects of two distinct ROCK inhibitors on HCC tumours was examined. Both fasudil and AT13148 significantly decreased tumour numbers, areas and volumes, but neither resulted in greater numbers of neutrophils or CD8+ T cells to be recruited. In the context of acute DEN-induced liver damage, AT13148 inhibited the recruitment of dendritic, natural killer and CD8⁺ T cells to livers. These observations indicate that there is an important role for ROCK1 cleavage to limit immunogenic cell death, which was not replicated by systemic ROCK inhibitor administration. As a result, concomitant administration of ROCK inhibitors with cancer therapeutics would be unlikely to result in therapeutic benefit by inducing ICD to increase anti-tumour immune responses.

Implication of non-coding RNA-mediated ROCK1 regulation in various diseases

Rho Associated Coiled-Coil Containing Protein Kinase 1 (ROCK1) is a protein serine/threonine kinase which is activated upon binding with the GTP-bound form of Rho. This protein can modulate actin-myosin contraction and stability. Moreover, it has a crucial role in the regulation of cell polarity. Therefore, it participates in modulation of cell morphology, regulation of expression of genes, cell proliferation and differentiation, apoptotic processes as well as oncogenic processes. Recent studies have highlighted interactions between ROCK1 and several non-coding RNAs, namely microRNAs, circular RNAs and long non-coding RNAs. Such interactions can be a target of medications. In fact, it seems that the interactions are implicated in therapeutic response to several medications. In the current review, we aimed to explain the impact of these interactions in the pathoetiology of cancers as well as non-malignant disorders.

Heterogeneous cancer-associated fibroblasts: A new perspective for understanding immunosuppression in pancreatic cancer

Immunotherapy has shown promising efficacy in the treatment of a wide range of cancers; however, it has had little effect on pancreatic cancer. Cancer-associated fibroblasts (CAFs), the predominant mesenchymal cells present in the pancreatic cancer microenvironment, are powerful supporters of the malignant progression of pancreatic cancer. CAFs can modify the microenvironment, establish a refuge to aid cancer cells in immune escape by secreting large amounts of extracellular matrix, and produce soluble cytokines and exosomal vesicles. Hence, CAFs are important contributors to the failure of immunotherapy. Current in-depth studies of CAFs have shown that CAFs are a heterogeneous population of mesenchymal cells; therefore, the functional complexity of their populations needs in-depth explorations in future studies. This review summarizes how heterogeneous CAFs help cancer cells achieve immune escape and suggests potential directions for using CAFs as targets to address immune escape.

CircRNA-Associated CeRNAs Regulatory Axes in Retinoblastoma: A Systematic Scoping Review

Retinoblastoma (RB) is one of the most common childhood cancers caused by RB gene mutations (tumor suppressor gene in various patients). A better understanding of molecular pathways and the development of new diagnostic approaches may lead to better treatment for RB patients. The number of studies on ceRNA axes is increasing, emphasizing the significance of these axes in RB. Circular RNAs (circRNAs) play a vital role in competing endogenous RNA (ceRNA) regulatory axes by sponging microRNAs and regulating gene expression. Because of the broadness of ceRNA interaction networks, they may assist in investigating treatment targets in RB. This study conducted a systematic scoping review to evaluate verified loops of ceRNA in RB, focusing on the ceRNA axis and its relationship to circRNAs. This scoping review was carried out using a six-step strategy and the Prisma guideline, and it involved systematically searching the publications of seven databases. Out of 363 records, sixteen articles were entirely consistent with the defined inclusion criteria and were summarized in the relevant table. The majority of the studies focused on the circRNAs circ_0000527, circ_0000034, and circTET1, with approximately two-fifths of the studies focusing on a single circRNA. Understanding the many features of this regulatory structure may help elucidate RB’s unknown causative factors and provide novel molecular potential therapeutic targets and medical fields.

Data driven and biophysical insights into the regulation of trafficking vesicles by extracellular matrix stiffness

Biomechanical signals from remodeled extracellular matrix (ECM) promote tumor progression. Here, we show that cell-matrix and cell-cell communication may be inherently linked and tuned through mechanisms of mechanosensitive biogenesis of trafficking vesicles. Pan-cancer analysis of cancer cells' mechanical properties (focusing primarily on cell stiffness) on substrates of varied stiffness and composition elucidated a heterogeneous cellular response to mechanical stimuli. Through machine learning, we identified a fingerprint of cytoskeleton-related proteins that accurately characterize cell stiffness in different ECM conditions. Expression of their respective genes correlates with patient prognosis across different tumor types. The levels of selected cytoskeleton proteins indicated that cortical tension mirrors the increase (or decrease) in cell stiffness with a change in ECM stiffness. A mechanistic biophysical model shows that the tendency for curvature generation by curvature-inducing proteins has an ultrasensitive dependence on cortical tension. This study thus highlights the effect of ECM stiffness, mediated by cortical tension, in modulating vesicle biogenesis.

Effects of RhoA on depression-like behavior in prenatally stressed offspring rats

Depression is a common mental disease that can lead to suicide when severe. Exposure to prenatal stress (PS) can lead to depression-like behavior in offspring, but the mechanism is unclear. RhoA (Ras homology family member A) plays an important role in stress-induced changes in synaptic plasticity, participating in the development of depression by activating the downstream effector ROCK (Rho-associated protein kinase). This study explored the influence in the expression of RhoA and downstream molecules ROCK1/2 in prenatally stressed rats, and the effect of RhoA inhibitor simvastatin on depression-like behavior induced by PS. Depression-like behavior in offspring was detected by sucrose preference test, forced swimming test, and open-field test. The mRNA and protein expression of RhoA and ROCK1/2 in the hippocampus and prefrontal cortex of offspring rats were detected by qRT-PCR and western blotting, respectively. Our results showed that PS causes depression-like behavior in offspring rats, associated with elevated expression of RhoA, ROCK1/2 in the hippocampus and prefrontal cortex. After administration of simvastatin to PS rats, the expression of RhoA and ROCK2 was significantly reduced, alleviating depression-like behavior. Our study demonstrated that RhoA participates in the depression-like behavior in prenatally stressed offspring rats, which may be a potential target for antidepressant therapy.

Prognostic and Immunological Role of PPP1R14A as a Pan-Cancer Analysis Candidate

Despite emerging evidence revealing the remarkable roles of protein phosphatase 1 regulatory inhibitor subunit 14A (PPP1R14A) in cancer tumorigenesis and progression, no pan-cancer analysis is available. A comprehensive investigation of the potential carcinogenic mechanism of PPP1R14A across 33 tumors using bioinformatic techniques is reported for the first time. PPP1R14A is downregulated in major malignancies, and there is a significant correlation between the PPP1R14A expression and the prognosis of patients. The high expression of PPP1R14A in most cases was associated with poor overall survival (OS), disease-specific survival (DSS), and progress-free interval (PFI) across patients with various malignant tumors, including adrenocortical carcinoma (ACC) and bladder urothelial carcinoma (BLCA), indicated through pan-cancer survival analysis. Receiver operating characteristic (ROC) analysis subsequently exhibited that the molecule has high reference significance in diagnosing a variety of cancers. The frequency of PPP1R14A genetic changes including genetic mutations and copy number alterations (CNAs) in uterine carcinosarcoma reached 16.07%, and these alterations brought misfortune to the survival and prognosis of cancer patients. In addition, methylation within the promoter region of PPP1R14A DNA was enhanced in a majority of cancers. Downregulated phosphorylation levels of phosphorylation sites including S26, T38, and others in most cases took place in several tumors, such as breast cancer and colon cancer. PPP1R14A remarkably correlated with the levels of infiltrating cells and immune checkpoint genes. Our research on the carcinogenic effect of PPP1R14A in different tumors is comprehensively summarized and analyzed and provides a theoretical basis for future therapeutic and immunotherapy strategies.

Cytoplasmic Clusterin Suppresses Lung Cancer Metastasis by Inhibiting the ROCK1-ERK Axis

Simple Summary

We show that CLU, especially cytoplasmic precursor CLU, is downregulated in lung cancer and correlates with poor survival. The silencing of CLU promotes lung cancer cell migration and invasion, while the overexpression of CLU potently inhibits these phenomena. Interestingly, secretory CLU proteins are slightly decreased in lung cancer tissue and fail to exert similar anti-metastatic effects like cytoplasmic precursor CLU, demonstrating that cytoplasmic precursor CLU is the primary functional isoform of CLU, which exerts the anti-metastatic effects of lung cancer. Mechanistically, cytoplasmic precursor CLU binds ROCK1 to decrease phosphorylation of ERK1/2 by inhibiting the kinase activity of ROCK1, leading to an anti-metastatic effect in lung cancer cells. These findings reveal a novel insight into the function and regulation of cytoplasmic CLU in lung cancer, which might be a potential target for the diagnosis and treatment of metastatic lung cancer.

Abstract

Clusterin (CLU) is a heterodimeric glycoprotein that has been detected in diverse human tissues and implicated in many cellular processes. Accumulating evidence indicates that the expression of secreted CLU correlates with the progression of cancers. However, the molecular mechanisms underlying its tumor-suppressive roles are incompletely uncovered. In this study, we demonstrate that precursor CLU is widely downregulated in lung cancer tissue, in which secretory CLU proteins are slightly decreased. Impressively, overexpressing CLU potently inhibits the migration, invasion and metastasis of lung cancer cells, whereas silencing CLU promotes this behavior; however, it appears that secretory CLU fails to exert similar anti-metastatic effects. Interestingly, the cytoplasmic precursor CLU binds ROCK1 to abrogate the interaction between ROCK1 and ERK and impair ERK activity, leading to the suppression of lung cancer invasiveness. Meanwhile, the expression of CLU was remarkably diminished in lung cancer bone metastasis loci when compared with subcutaneous tumors in the mouse model and hardly detected in the bone metastasis loci of lung cancer patients when compared with the primary. These findings reveal a novel insight into the function and regulation of cytoplasmic CLU in lung cancer, which might be a potential target for the diagnosis and treatment of metastatic lung cancer.

The Small GTPase RHOA Links SLP65 Activation to PTEN Function in Pre B Cells and Is Essential for the Generation and Survival of Normal and Malignant B Cells

The generation, differentiation, survival and activation of B cells are coordinated by signals emerging from the B cell antigen receptor (BCR) or its precursor, the pre-BCR. The adaptor protein SLP65 (also known as BLNK) is an important signaling factor that controls pre-B cell differentiation by down-regulation of PI3K signaling. Here, we investigated the mechanism by which SLP65 interferes with PI3K signaling. We found that SLP65 induces the activity of the small GTPase RHOA, which activates PTEN, a negative regulator of PI3K signaling, by enabling its translocation to the plasma membrane. The essential role of RHOA is confirmed by the complete block in early B cell development in conditional RhoA-deficient mice. The RhoA-deficient progenitor B cells showed defects in activation of immunoglobulin gene rearrangement and fail to survive both in vitro and in vivo. Reconstituting the RhoA-deficient cells with RhoA or Foxo1, a transcription factor repressed by PI3K signaling and activated by PTEN, completely restores the survival defect. However, the defect in differentiation can only be restored by RhoA suggesting a unique role for RHOA in B cell generation and selection. In full agreement, conditional RhoA-deficient mice develop increased amounts of autoreactive antibodies with age. RHOA function is also required at later stage, as inactivation of RhoA in peripheral B cells or in a transformed mature B cell line resulted in cell loss. Together, these data show that RHOA is the key signaling factor for B cell development and function by providing a crucial SLP65-activated link between BCR signaling and activation of PTEN. Moreover, the identified essential role of RHOA for the survival of transformed B cells offers the opportunity for targeting B cell malignancies by blocking RHOA function.

HNRNPC regulates RhoA to induce DNA damage repair and cancer-associated fibroblast activation causing radiation resistance in pancreatic cancer

Pancreatic cancer (PC) is one of the most lethal types of cancer due to its asymptomatic nature in the early stages and consequent late diagnosis. Its mortality rate remains high despite advances in treatment strategies, which include a combination of surgical resection and adjuvant therapy. Although these approaches may have a positive effect on prognosis, the development of chemo- and radioresistance still poses a significant challenge for successful PC treatment. Heterogeneous nuclear ribonucleoprotein C1/C2 (HNRNPC) and RhoA have been implicated in the regulation of tumour cell proliferation and chemo- and radioresistance. Our study aims to investigate the mechanism for HNRNPC regulation of PC radiation resistance via the RhoA pathway. We found that HNRNPC and RhoA mRNA and protein expression levels were significantly higher in PC tissues compared to adjacent non-tumour tissue. Furthermore, high HNRNPC expression was associated with poor patient prognosis. Using HNRNPC overexpression and siRNA interference, we demonstrated that HNRNPC overexpression promoted radiation resistance in PC cells, while HNRNPC knockdown increased radiosensitivity. However, silencing of RhoA expression was shown to attenuate radiation resistance caused by HNRNPC overexpression. Next, we identified RhoA as a downstream target of HNRNPC and showed that inhibition of the RhoA/ROCK2-YAP/TAZ pathway led to a reduction in DNA damage repair and radiation resistance. Finally, using both in vitro assays and an in vivo subcutaneous tumour xenograft model, we demonstrated that RhoA inhibition can hinder the activity of cancer-related fibroblasts and weaken PC radiation resistance. Our study describes a role for HNRNPC and the RhoA/ROCK2-YAP/TAZ signalling pathways in mediating radiation resistance and provides a potential therapeutic target for improving the treatment of PC.

RhoA/ROCK signaling antagonizes bovine trophoblast stem cell self-renewal and regulates preimplantation embryo size and differentiation

Exponential proliferation of trophoblast stem cells (TSC) is crucial in Ruminantia to maximize numerical access to caruncles, the restricted uterine sites that permit implantation. When translating systems biology of the undifferentiated bovine trophectoderm, we uncovered that inhibition of RhoA/Rock promoted self-renewing proliferation and substantially increased blastocyst size. Analysis of transcripts suppressed by Rock inhibition revealed transforming growth factor β1 (TGFβ1) as a primary upstream effector. TGFβ1 treatment induced changes consistent with differentiation in bTSCs, a response that could be replicated by induced expression of the bovine ROCK2 transgene. Rocki could partially antagonize TGFβ1 effects, and TGFβ receptor inhibition promoted proliferation identical to Rocki, indicating an all-encompassing upstream regulation. Morphological differentiation included formation of binucleate cells and infrequent multinucleate syncytia, features we also localize in the in vivo bovine placenta. Collectively, we demonstrate a central role for TGFβ1, RhoA and Rock in inducing bTSC differentiation, attenuation of which is sufficient to sustain self-renewal and proliferation linked to blastocyst size and preimplantation development. Unraveling these mechanisms augments evolutionary/comparative physiology of the trophoblast cell lineage and placental development in eutherians.

miR-802 Suppresses Acinar-to-Ductal Reprogramming During Early Pancreatitis and Pancreatic Carcinogenesis

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive tumor that is almost uniformly lethal in humans. Activating mutations of KRAS are found in >90% of human PDACs and are sufficient to promote acinar-to-ductal metaplasia (ADM) during tumor initiation. The roles of miRNAs in oncogenic Kras-induced ADM are incompletely understood.

METHODS

The Ptf1a^Cre/+LSL-Kras^G12D/+ and Ptf1a^Cre/+LSL-Kras^G12D/+LSL-p53R172H/⁺ and caerulein-induced acute pancreatitis mice models were used. mir-802 was conditionally ablated in acinar cells to study the function of miR-802 in ADM.

RESULTS

We show that miR-802 is a highly abundant and acinar-enriched pancreatic miRNA that is silenced during early stages of injury or oncogenic Kras^G12D-induced transformation. Genetic ablation of mir-802 cooperates with Kras^G12D by promoting ADM formation. miR-802 deficiency results in de-repression of the miR-802 targets Arhgef12, RhoA, and Sdc4, activation of RhoA, and induction of the downstream RhoA effectors ROCK1, LIMK1, COFILIN1, and EZRIN, thereby increasing F-actin rearrangement. mir-802 ablation also activates SOX9, resulting in augmented levels of ductal and attenuated expression of acinar identity genes. Consistently with these findings, we show that this miR-802-RhoA-F-actin network is activated in biopsies of pancreatic cancer patients and correlates with poor survival.

CONCLUSIONS

We show miR-802 suppresses pancreatic cancer initiation by repressing oncogenic Kras-induced ADM. The role of miR-802 in ADM fills the gap in our understanding of oncogenic Kras-induced F-actin reorganization, acinar reprogramming, and PDAC initiation. Modulation of the miR-802-RhoA-F-actin network may be a new strategy to interfere with pancreatic carcinogenesis.

Generation of a lung squamous cell carcinoma three-dimensional culture model with keratinizing structures

Tumor nests in lung squamous cell carcinoma (LUSC) have a hierarchical structure resembling squamous epithelium. The nests consist of basal-like cells on the periphery and layers of keratinocyte-like cells that differentiate towards the center of the nest, forming keratin pearls. Reproducing this spatial heterogeneity in in vitro models would be useful for understanding the biology of LUSC. Here, we established a three-dimensional (3D) culture model with a squamous epithelial structure using LUSC cell lines PLR327F-LD41 and MCC001F, established in-house. When PLR327F-LD41 cells were cultured in a mixture of Matrigel and collagen I, they generated 3D colonies (designated cancer organoids, or COs) with involucrin (IVL)-positive keratinizing cells in the center (IVL^inner COs). COs with uniform size were generated by seeding PLR327F-LD41 cells in a form of small cell aggregates. Since Notch signaling induces the differentiation of squamous epithelium, we confirmed the effect of γ-secretase inhibitor in inhibiting Notch signaling in IVL^inner COs. Surprisingly, γ-secretase inhibitor did not block induction of IVL-positive cells; however, cells residing between the CK5-positive basal-like layer and IVL-positive layer decreased significantly. Thus, our 3D culture model with uniform size and structure promises to be a useful tool for elucidating the biology of LUSC and for screening drug-candidates.

miRNA-148b and its role in various cancers

miRNA-148b belongs to the family miR-148/-152, with significant differences in nonseed sequences, which can target diverse mRNA molecules. Reportedly, it may undergo deregulation in lung and ovarian cancers and downregulation in gastric, pancreatic and colon cancers. However, there is a need for further studies to better characterize its mechanism of action and in different types of cancer. In this review, we focus on the aberrant expression of miR-148b in different cancer types and highlight its main target genes and signaling pathways, as well as its pathophysiologic role and relevance to tumorigenesis in several types of cancer.

AAMP promotes colorectal cancer metastasis by suppressing SMURF2-mediated ubiquitination and degradation of RhoA

Metastasis is considered the leading cause of cancer death due to the limited possibilities to therapeutically target this process. How the ubiquitination machinery contributes to metastasis remains underexplored. Angio-associated migratory cell protein (AAMP), a ubiquitously expressed protein involved in cell migration, has been reported to play oncogenic roles in breast and non-small cell lung cancer (NSCLC). However, the role of AAMP in colorectal cancer (CRC) has not been demonstrated. Here, we report that AAMP is aberrantly upregulated in metastatic CRC and that AAMP upregulation is correlated with the poor survival of CRC patients. AAMP knockdown significantly attenuated the migration and invasion of CRC cells, while AAMP overexpression led to the opposite effects. Mechanistically, we identified Ras homolog family member A (RhoA) as a target of AAMP. Smad ubiquitin regulatory factor (SMURF) 2 was previously found to be a CRC suppressor. Notably, we discovered here that SMURF2 acted as an E3 ubiquitin ligase to mediate the ubiquitination and degradation of RhoA. AAMP stabilized RhoA by binding to it and suppressing its SMURF2-mediated ubiquitination and degradation. Subsequently, the level of active RhoA was increased, thereby accelerating CRC cell migration and invasion. These findings indicate a new potential antitumor target for CRC.

Isoprenylcysteine carboxyl methyltransferase promotes the progression of tongue squamous cell carcinoma via the K-Ras and RhoA signaling pathways

OBJECTIVE

This research investigated the biological role of isoprenylcysteine carboxyl methyltransferase (ICMT) in tongue squamous cell carcinoma (TSCC) progression meanwhile to explore the conceivable mechanism.

METHODS

The mRNA and protein expression were measured using real-time PCR and Western blot. Cell proliferation, apoptosis, cycle distribution, migration and invasion were evaluated by CCK-8 assay, flow cytometry, wound-healing assay and transwell assay. The anti-tumor activity of ICMT silencing was observed in nude mice.

RESULTS

Our results indicated that silencing of ICMT-mediated methylation effectively inhibited TSCC cells proliferation in vitro and reduced tumor growth in vivo. Moreover, ICMT knockdown also induced cell apoptosis and cell cycle arrest of both CAL-27 and SCC-4 cells. In addition, CAL-27 and SCC-4 cells migration and invasion were weakened by ICMT siRNA. Mechanistically, ICMT deficiency significantly decreased the K-Ras and RhoA membrane targeting localization, leading to the suppression of K-Ras- and RhoA-mediated downstream signaling in CAL-27 and SCC-4 cells.

CONCLUSIONS

Altogether, our findings identified a crucial role played by ICMT in the progression of TSCC and the potential mechanisms by which exerted its effects, indicating that targeting ICMT may represent a promising therapeutic strategy for TSCC.

Conditional deletion of ROCK2 induces anxiety-like behaviors and alters dendritic spine density and morphology on CA1 pyramidal neurons

Rho-associated kinase isoform 2 (ROCK2) is an attractive drug target for several neurologic disorders. A critical barrier to ROCK2-based research and therapeutics is the lack of a mouse model that enables investigation of ROCK2 with spatial and temporal control of gene expression. To overcome this, we generated ROCK2fl/fl mice. Mice expressing Cre recombinase in forebrain excitatory neurons (CaMKII-Cre) were crossed with ROCK2fl/fl mice (Cre/ROCK2fl/fl), and the contribution of ROCK2 in behavior as well as dendritic spine morphology in the hippocampus, medial prefrontal cortex (mPFC), and basolateral amygdala (BLA) was examined. Cre/ROCK2fl/fl mice spent reduced time in the open arms of the elevated plus maze and increased time in the dark of the light-dark box test compared to littermate controls. These results indicated that Cre/ROCK2fl/fl mice exhibited anxiety-like behaviors. To examine dendritic spine morphology, individual pyramidal neurons in CA1 hippocampus, mPFC, and the BLA were targeted for iontophoretic microinjection of fluorescent dye, followed by high-resolution confocal microscopy and neuronal 3D reconstructions for morphometry analysis. In dorsal CA1, Cre/ROCK2fl/fl mice displayed significantly increased thin spine density on basal dendrites and reduced mean spine head volume across all spine types on apical dendrites. In ventral CA1, Cre/ROCK2fl/fl mice exhibited significantly increased spine length on apical dendrites. Spine density and morphology were comparable in the mPFC and BLA between both genotypes. These findings suggest that neuronal ROCK2 mediates spine density and morphology in a compartmentalized manner among CA1 pyramidal cells, and that in the absence of ROCK2 these mechanisms may contribute to anxiety-like behaviors.

miR-125b Promotes Colorectal Cancer Migration and Invasion by Dual-Targeting CFTR and CGN

Simple Summary

Colorectal cancer (CRC) is the third leading cause for cancer related death, in which metastasis exerts a pivotal role. Therefore, we aim to find out the possible mechanism underlying CRC metastasis. We found that the level of miR-125b was elevated in normal, primary CRC, and distant metastasis tissues stepwise, and high level miR-125b was positively correlated with lymph node metastasis and tumor differentiation. In vitro and in vivo assays showed miR-125b significantly promoted CRC migration and invasion. To elucidate the potential mechanism, cystic fibrosis transmembrane conductance regulator (CFTR) and cingulin (CGN) were defined as two target genes of miR-125b. On the one hand, miR-125b promoted epithelial-mesenchymal transition (EMT) and the production and secretion of urokinase plasminogen activator (uPA) by inhibiting CFTR; on the other hand, miR-125b activated Ras Homolog Family Member A (RhoA)/Rho Kinase (ROCK) signaling by repressing CGN. Therefore, we provided a potential biomarker for CRC prevention and treatment in the future.

Abstract

Metastasis contributes to the poor prognosis of colorectal cancer, the causative factor of which is not fully understood. Previously, we found that miR-125b (Accession number: MIMAT0000423) contributed to cetuximab resistance in colorectal cancer (CRC). In this study, we identified a novel mechanism by which miR-125b enhances metastasis by targeting cystic fibrosis transmembrane conductance regulator (CFTR) and the tight junction-associated adaptor cingulin (CGN) in CRC. We found that miR-125b expression was upregulated in primary CRC tumors and metastatic sites compared with adjacent normal tissues. Overexpression of miR-125b in CRC cells enhanced migration capacity, while knockdown of miR-125b decreased migration and invasion. RNA-sequencing (RNA-seq) and dual-luciferase reporter assays identified CFTR and CGN as the target genes of miR-125b, and the inhibitory impact of CFTR and CGN on metastasis was further verified both in vitro and in vivo. Moreover, we found that miR-125b facilitated the epithelial-mesenchymal transition (EMT) process and the expression and secretion of urokinase plasminogen activator (uPA) by targeting CFTR and enhanced the Ras Homolog Family Member A (RhoA)/Rho Kinase (ROCK) pathway activity by targeting CGN. Together, these findings suggest miR-125b as a key functional molecule in CRC and a promising biomarker for the diagnosis and treatment of CRC.

Exploring the therapeutic promise of targeting Rho kinase in rheumatoid arthritis

Rheumatoid arthritis (RA) is a prevalent systemic autoimmune disease caused by dysregulated inflammatory reactions, T lymphocyte invasion into the joints, and articular thickening. Immune cells, primarily tumor necrosis factor-alpha (TNF-α) and chemokines (interleukin or IL-1), which are predominantly generated by activated macrophages cells, have also been involved with the pathogenesis of rheumatoid arthritis. Rho GTPases are integral factors of biochemical cascades utilized by antigens, and also by cellular receptors, cytokines, and chemokines, to modulate inflammatory reactions, according to growing data. The Rho family is a group of G proteins that govern a variety of biological and physiological activities such as mobility, actin stress fiber production, growth, and polarity. Research suggests that the Rho A and Rho-associated coiled-coil kinase (ROCK) regulatory cascade could be essential in several autoimmune conditions, including RA. ROCK is activated in the synovial of rheumatoid arthritis patients, while the blocking of ROCK with fasudil could also decrease IL-6, TNF-α, and IL-1. This review covers current developments in understanding the overactivation of Rho enzyme activity in RA suppressed by ROCK inhibitors which can be utilized for the treatment of autoimmune disease. We offer an outline of the function of ROCK inhibitors in immune cells and discuss findings which emphasize the rising participation of this category of kinases within the pathological process of autoimmune disorders. Assuming the potential ability of ROCK as a therapeutic, we define approaches that might be used to inhibit Rho kinase activity in rheumatoid disorders.

DJ4 Targets the Rho-Associated Protein Kinase Pathway and Attenuates Disease Progression in Preclinical Murine Models of Acute Myeloid Leukemia

The poor prognosis of acute myeloid leukemia (AML) and the highly heterogenous nature of the disease motivates targeted gene therapeutic investigations. Rho-associated protein kinases (ROCKs) are crucial for various actin cytoskeletal changes, which have established malignant consequences in various cancers, yet are still not being successfully utilized clinically towards cancer treatment. This work establishes the therapeutic activity of ROCK inhibitor (5Z)-2-5-(1H-pyrrolo[2,3-b]pyridine-3-ylmethylene)-1,3-thiazol-4(5H)-one (DJ4) in both in vitro and in vivo preclinical models of AML to highlight the potential of this class of inhibitors. Herein, DJ4 induced cytotoxic and proapoptotic effects in a dose-dependent manner in human AML cell lines (IC50: 0.05-1.68 μM) and primary patient cells (IC50: 0.264-13.43 μM); however, normal hematopoietic cells were largely spared. ROCK inhibition by DJ4 disrupts the phosphorylation of downstream targets, myosin light chain (MLC2) and myosin-binding subunit of MLC phosphatase (MYPT), yielding a potent yet selective treatment response at micromolar concentrations, from 0.02 to 1 μM. Murine models injected with luciferase-expressing leukemia cell lines subcutaneously or intravenously and treated with DJ4 exhibited an increase in overall survival and reduction in disease progression relative to the vehicle-treated control mice. Overall, DJ4 is a promising candidate to utilize in future investigations to advance the current AML therapy.

Design, synthesis, and biological evaluation of urea-based ROCK2 inhibitors

A series of urea-based ROCK2 inhibitors were design and synthesized. The inhibitory activity on ROCK2 was screened by enzyme-linked immunosorbent assay (ELISA). The study results showed that the urea derivatives exhibited certain ROCK2 inhibitory activity. The most potent compound 10p showed ROCK2 inhibitory activity with the IC₅₀  value of 0.03 μM. A preliminary structure-activity relationship was then summarized. The molecular docking studies showed that further optimization needs to conduct to obtain more potent ROCK inhibitors.

LncRNA MAGI2-AS3 is downregulated in the distant recurrence of hepatocellular carcinoma after surgical resection and affects migration and invasion via ROCK2

INTRODUCTION AND OBJECTIVES

Hepatocellular carcinoma (HCC) is the second most lethal cancer around the world, with poor survival rate and high metastasis rate in patients. Long noncoding RNAs (lncRNAs) have been reported to modulate the initiation and development of liver cancer. We aimed to investigate the role of lncRNA MAGI2-AS3 in HCC and underlying mechanisms.

MATERIALS AND METHODS

The expression levels of MAGI2-AS3 in plasma of HCC patients and the control participants were measured by qPCR. Hep3B and MHCC97-H cells were transfected with MAGI2-AS3 and ROCK2 expression vectors. Cell migration and invasion of HCC cells transfected with the vectors were investigated by transwell assay. In addition, flow cytometry and western blot were performed for apoptosis detection.

RESULTS

We found that MAGI2-AS3 was downregulated in plasma of early stage HCC patients compared to healthy controls. After surgical resection, the expression levels of MAGI2-AS3 were increased compared to pretreatment levels on the day of discharge. During the follow-up, MAGI2-AS3 was downregulated in patients developed distant recurrence, but not in other patients compared to the levels measured on the day of discharge. In HCC cells, overexpression of MAGI2-AS3 mediated the downregulation of ROCK2. Cell invasion and migration assay showed that overexpression of MAGI2-AS3 mediated the decreased cell invasion and migration rate, while ROCK2 played an opposite role and attenuated the effects of overexpression of MAGI2-AS3.

CONCLUSION

Our study indicated that MAGI2-AS3 was downregulated in the distant recurrence of HCC after surgical resection and affected the invasion and migration of HCC cells via ROCK2.

Intravitreal Fasudil for Treatment of Diabetic Macular Edema with an Unfavorable Response

PURPOSE

This study evaluates the effect of intravitreal injection of a Rho-associated protein kinase (ROCK) inhibitor, fasudil, on diabetic macular edema (DME) with an unfavorable response.

METHODS

This study included 14 eyes of 13 patients (mean age: 65.7 ± 5.2 years) with DME, and eligible eyes underwent single intravitreal injection of 0.025 mg fasudil. The best-corrected visual acuity (BCVA), intraocular pressure (IOP), and central macular thickness (CMT) were evaluated before and 1, 2, and 3 months after treatment. The standard automated perimetry (SAP) results and maximal response of the electroretinogram (ERG) were recorded before and 3 months after treatment.

RESULTS

The BCVA, IOP, and CMT remained unchanged during the study period. Similarly, the mean deviation obtained by SAP and each ERG parameter did not show significant changes after the treatment.

CONCLUSIONS

Although single intravitreal fasudil injection failed to show therapeutic benefits in DME, it seemed to have no negative effect on the retina.

A preclinical pipeline to evaluate migrastatics as therapeutic agents in metastatic melanoma

BACKGROUND

Metastasis is a hallmark of cancer and responsible for most cancer deaths. Migrastatics were defined as drugs interfering with all modes of cancer cell invasion and thus cancers' ability to metastasise. First anti-metastatic treatments have recently been approved.

METHODS

We used bioinformatic analyses of publicly available melanoma databases. Experimentally, we performed in vitro target validation (including 2.5D cell morphology analysis and mass spectrometric analysis of RhoA binding partners), developed a new traceable spontaneously metastasising murine melanoma model for in vivo validation, and employed histology (haematoxylin/eosin and phospho-myosin II staining) to confirm drug action in harvested tumour tissues.

RESULTS

Unbiased and targeted bioinformatic analyses identified the Rho kinase (ROCK)-myosin II pathway and its various components as potentially relevant targets in melanoma. In vitro validation demonstrated redundancy of several RhoGEFs upstream of RhoA and confirmed ROCK as a druggable target downstream of RhoA. The anti-metastatic effects of two ROCK inhibitors were demonstrated through in vivo melanoma metastasis tracking and inhibitor effects also confirmed ex vivo by digital pathology.

CONCLUSIONS

We proposed a migrastatic drug development pipeline. As part of the pipeline, we provide a new traceable spontaneous melanoma metastasis model for in vivo quantification of metastasis and anti-metastatic effects by non-invasive imaging.

Overexpression of ROCK1 promotes cancer cell proliferation and is associated with poor prognosis in human urothelial bladder cancer

Rho-associated protein kinase 1 (ROCK1) has been reported to be overexpressed in many types of tumors, but its role in urothelial bladder cancer is poorly understood. The study aims to investigate the role of ROCK1 in urothelial bladder cancer and explored the underlying mechanism. Protein and mRNA levels of ROCK1 were detected in 64 urothelial bladder cancer patients using western blot, immunohistochemistry and qRT-PCR. Relationships between ROCK1 expression and clinicopathological factors and survival rate were analyzed. ROCK1 was silenced by shRNA in multiple urothelial bladder cancer cells to explore its function and underlying mechanism. ROCK1 expression was significantly increased in tumor tissues compared with the paired adjacent healthy tissues of patients. Higher ROCK1 expression of tumor tissues positively correlated with poor prognosis of patients (p = 0.0435). ROCK1 silence significantly inhibited cell proliferation and colony formation, and enhanced activation of apoptotic pathway in urothelial bladder cancer cells. High ROCK1 expression predicts poor prognosis of urothelial bladder cancer. ROCK1 silence inhibit cell proliferation and promote apoptosis, which may be of value as a therapeutic target for bladder cancer treatment.

Predicting Agents That Can Overcome 5-FU Resistance in Colorectal Cancers via Pharmacogenomic Analysis

5-Fluorouracil (5-FU) is one of several chemotherapeutic agents in clinical use as a standard of care to treat colorectal cancers (CRCs). As an antimetabolite, 5-FU inhibits thymidylate synthase to disrupt the synthesis and repair of DNA and RNA. However, only a small proportion of patients benefit from 5-FU treatment due to the development of drug resistance. This study applied pharmacogenomic analysis using two public resources, the Genomics of Drug Sensitivity in Cancer (GDSC) and the Connectivity Map, to predict agents overcoming 5-FU resistance in CRC cells based on their genetic background or gene expression profile. Based on the genetic status of adenomatous polyposis coli (APC), the most frequent mutated gene found in CRC, we found that combining a MEK inhibitor with 5-FU exhibited synergism effects on CRC cells with APC truncations. While considering the gene expression in 5-FU resistant cells, we demonstrated that targeting ROCK is a potential avenue to restore 5-FU response to resistant cells with wild-type APC background. Our results reveal MEK signaling plays a pivotal role in loss-of-function, APC-mediated 5-FU resistance, and ROCK activation serves as a signature in APC-independent 5-FU resistance. Through the use of these available database resources, we highlight possible approaches to predict potential drugs for combinatorial therapy for patients developing resistance to 5-FU treatment.

LncRNA MCM3AP-AS1 sponges miR-148a to enhance cell invasion and migration in small cell lung cancer

Background

MCM3AP-AS1 is a recently characterized lncRNA playing an oncogenic role in several cancers. However, its role in lung cancer remains unknown. Here, we aimed to explore the functions of MCM3AP-AS1 in small cell lung cancer (SCLC) and the possible underlying mechanisms.

Methods

MCM3AP-AS1 and ROCK1 levels in SCLC patients were analyzed by qPCR. RNA pull-down and luciferase assays were performed to analyze the interaction between MCM3AP-AS1 and miR-148a. ROCK1 mRNA and protein levels were detected by qPCR and Western blot, respectively. Cell invasion and migration were analyzed by Transwell assays.

Results

MCM3AP-AS1 was upregulated in patients with SCLC, and a high MCM3AP-AS1 level was accompanied by a low survival rate. The binding of MCM3AP-AS1 to miR-148a predicted by bioinformatics analysis was verified by RNA pull-down and luciferase assays. However, MCM3AP-AS1 and miR-148a did not affect each other’s expression. ROCK1 was upregulated in SCLC tissues and positively correlated with MCM3AP-AS1. In SCLC cells, MCM3AP-AS1 overexpression increased ROCK1 and promoted cancer cell invasion and migration, while miR-148a overexpression showed the opposite effects and attenuated the effects of MCM3AP-AS1 overexpression on ROCK1 expression and cell behaviors.

Conclusions

MCM3AP-AS1 sponges miR-148a, thereby increasing SCLC cell invasion and migration via upregulating ROCK1 expression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08365-8.

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.