Suppression of Angiogenesis by Targeting Cyclin-Dependent Kinase 7 in Human Umbilical Vein Endothelial Cells and Renal Cell Carcinoma: An In Vitro and In Vivo Study

LPAR3 and COL8A1, as matrix stiffness-related biomarkers, promote nasopharyngeal carcinoma metastasis by triggering EMT and angiogenesis

Matrix stiffness affects the progression of nasopharyngeal carcinoma, but the underlying mechanism is still unknown. Here, we demonstrated that nasopharyngeal carcinoma tissues with distant metastasis contain large collagen deposits and strong matrix stiffness. First, we performed RNA-seq analysis of nasopharyngeal carcinoma cells cultured on polyacrylamide hydrogel systems and found that LPAR3 and COL8A1 are potential matrix stiffness markers. Based on in vivo and in vitro experiments, matrix stiffness mainly affected tumor metastasis rather than proliferation. Subsequently, we found that matrix stiffness triggers the formation of epithelial-mesenchymal transition by increasing the expression of LPAR3 in nasopharyngeal carcinoma, which is related to metastasis. In addition, matrix stiffness promotes the expression of COL8A1 secreted by nasopharyngeal carcinoma and is related to tumor angiogenesis. Simultaneous inhibition of LPAR3 and COL8A1 genes significantly reduced nasopharyngeal carcinoma invasion and metastasis. Based on the investigation, we confirmed that matrix stiffness governs the progression of nasopharyngeal carcinoma and that LPAR3 and COL8A1, as matrix stiffness related biomarkers, promote nasopharyngeal carcinoma metastasis by inducing epithelial-mesenchymal transition and angiogenesis. Overall, the in-depth exploration of matrix stiffness may provide a strategy for clinical treatment intervention and provide promising targets for clinical nasopharyngeal carcinoma treatment.

Cyclin-dependent kinases as mediators of aberrant transcription in prostate cancer

Transcriptional control of gene expression is fundamental to all cellular processes. Conversely, transcriptional dysregulation is a hallmark of cancer. While this hallmark is a key driver of all malignancy-related process, it also represents a vulnerability that can be exploited therapeutically. Prostate cancer is a prime example of this phenomenon: it is characterised by aberrant transcription and treated with drugs that influence transcriptional pathways. Indeed, the primary oncogenic driver and therapeutic target of prostate cancer, the androgen receptor (AR), is a transcription factor. Moreover, a plethora of other transcriptional regulators, including transcriptional cyclin-dependent kinases (CDK7, CDK8 and CDK9), MYC and Bromodomain-containing protein 4 (BRD4), play prominent roles in disease progression. In this review, we focus on the roles of transcriptional CDKs in prostate cancer growth, metastasis and therapy resistance and discuss their interplay with AR, MYC and BRD4. Additionally, we explore recent advances in the therapeutic targeting of transcriptional CDKs and propose how these strategies could be effectively harnessed for the treatment of prostate cancer.

IL-35 enhances angiogenic effects of small extracellular vesicles in breast cancer

As an indispensable process for breast cancer metastasis, tumour angiogenesis requires a tight interaction between cancer cells and endothelial cells in tumour microenvironment. Here, we explored the participation of small extracellular vesicles (sEVs) derived from breast cancer cells in modulating angiogenesis and investigated the effect of IL-35 in facilitating this process. Firstly, we characterized breast cancer cells-derived sEVs untreated or treated with IL-35 and visualized the internalization of these sEVs by human umbilical vein endothelial cells (HUVECs). Breast cancer cells-derived sEVs promoted endothelial cell proliferation through facilitating cell cycle progression and enhanced capillary-like structures formation and microvessel formation. Subsequent results proved that IL-35 further reinforced the angiogenic effect induced by breast cancer cells-derived sEVs. Moreover, sEVs from breast cancer cells significantly enhanced tumour growth and microvessel density in breast tumour-bearing mice model. Microarray analysis showed that IL-35 might alter the mRNA profiles of sEVs and activate the Ras/Raf/MEK/ERK signalling pathway. These findings demonstrated that IL-35 indirectly promoted angiogenesis in breast cancer through regulating the content of breast cancer cells-derived sEVs, which could be internalized by HUVECs.

Nuclear exosome HMGB3 secreted by nasopharyngeal carcinoma cells promotes tumour metastasis by inducing angiogenesis

Distant metastasis accompanied by angiogenesis is the main cause of nasopharyngeal carcinoma (NPC)-related death. Nuclear exosomes (nEXOs) are potential tumour biomarkers. High mobility group box 3 (HMGB3), a nuclear protein, is known to be overexpressed in cancers. However, its role in NPC has not been elucidated. Here, we explore for the first time the function of nEXO HMGB3 in tumour angiogenesis involved in NPC metastasis using a series of in vitro experiments with NPC cell lines and clinical specimens and in vivo experiments with tumour xenograft zebrafish angiogenesis model. We found a high expression of HMGB3 in NPC, accompanied by the formation of micronuclei, to be associated with metastasis. Furthermore, the NPC-secreted HMGB3 expression was associated with tumour angiogenesis. Moreover, HMGB3-containing nEXOs, derived from the micronuclei of NPC cells, were ingested by the human umbilical vein endothelial cells (HUVECs), and accelerated angiogenesis in vitro and in vivo. Importantly, western blotting and flow cytometry analysis showed that circulating nEXO HMGB3 positively correlated with NPC metastasis. In summary, nEXO HMGB3 can be a significant biomarker of NPC metastasis and provide a novel basis for anti-angiogenesis therapy in clinical metastasis.

A dual-targeting ruthenium nanodrug that inhibits primary tumor growth and lung metastasis via the PARP/ATM pathway

Background

Many studies have found that ruthenium complexes possess unique biochemical characteristics and inhibit tumor growth or metastasis.

Results

Here, we report the novel dual-targeting ruthenium candidate 2b, which has both antitumor and antimetastatic properties and targets tumor sites through the enhanced permeability and retention (EPR) effect and transferrin/transferrin receptor (TF/TFR) interaction. The candidate 2b is composed of ruthenium-complexed carboline acid and four chloride ions. In vitro, 2b triggered DNA cleavage and thus blocked cell cycle progression and induced apoptosis via the PARP/ATM pathway. In vivo,2b inhibited not only Lewis lung cancer (LLC) tumor growth but also lung metastasis. We detected apoptosis and decreased CD31 expression in tumor tissues, and ruthenium accumulated in the primary tumor tissue of C57BL/6 mice implanted with LLC cells.

Conclusions

Thus, we conclude that 2b targets tumors, inhibits tumor growth and prevents lung metastasis.

Recent progress in development of cyclin-dependent kinase 7 inhibitors for cancer therapy

Introduction: Cyclin-dependent kinase 7 (CDK7) is a part of the CDK-activating kinase family (CAK) which has a key role in the cell cycle and transcriptional regulation. Several lines of evidence suggest that CDK7 is a promising therapeutic target for cancer. CDK7 selective inhibitors such as SY-5609 and CT7001 are in clinical development. Areas covered: We explore the biology of CDK7 and its role in cancer and follow this with an evaluation of the preclinical and clinical progress of CDK7 inhibitors, and their potential in the clinic. We searched PubMed and ClinicalTrials to identify relevant data from the database inception to 14 October 2020. Expert opinion: CDK7 inhibitors are next generation therapeutics for cancer. However, there are still challenges which include selectively, side effects, and drug resistance. Nevertheless, with ongoing clinical development of these inhibitors and greater analysis of their target, CDK7 inhibitors will become a promising approach for treatment of cancer in the near future.

Cellular and Molecular Mechanisms of R/S-Roscovitine and CDKs Related Inhibition under Both Focal and Global Cerebral Ischemia: A Focus on Neurovascular Unit and Immune Cells

Ischemic stroke is the second leading cause of death worldwide. Following ischemic stroke, Neurovascular Unit (NVU) inflammation and peripheral leucocytes infiltration are major contributors to the extension of brain lesions. For a long time restricted to neurons, the 10 past years have shown the emergence of an increasing number of studies focusing on the role of Cyclin-Dependent Kinases (CDKs) on the other cells of NVU, as well as on the leucocytes. The most widely used CDKs inhibitor, (R)-roscovitine, and its (S) isomer both decreased brain lesions in models of global and focal cerebral ischemia. We previously showed that (S)-roscovitine acted, at least, by modulating NVU response to ischemia. Interestingly, roscovitine was shown to decrease leucocytes-mediated inflammation in several inflammatory models. Specific inhibition of roscovitine majors target CDK 1, 2, 5, 7, and 9 showed that these CDKs played key roles in inflammatory processes of NVU cells and leucocytes after brain lesions, including ischemic stroke. The data summarized here support the investigation of roscovitine as a potential therapeutic agent for the treatment of ischemic stroke, and provide an overview of CDK 1, 2, 5, 7, and 9 functions in brain cells and leucocytes during cerebral ischemia.

Effects of FTMT Expression by Retinal Pigment Epithelial Cells on Features of Angiogenesis

Aberrant angiogenesis is a pathological feature of a number of diseases and arises from the uncoordinated expression of angiogenic factors as response to different cellular stresses. Age-related macular degeneration (AMD), a leading cause of vision loss, can result from pathological angiogenesis. As a mutation in the mitochondrial ferritin (FTMT) gene has been associated with AMD, its possible role in modulating angiogenic factors and angiogenesis was investigated. FTMT is an iron-sequestering protein primarily expressed in metabolically active cells and tissues with high oxygen demand, including retina. In this study, we utilized the human retinal pigment epithelial cell line ARPE-19, both as undifferentiated and differentiated cells. The effects of proinflammatory cytokines, FTMT knockdown, and transient and stable overexpression of FTMT were investigated on expression of pro-angiogenic vascular endothelial growth factor (VEGF) and anti-angiogenic pigment epithelial-derived factor (PEDF). Proinflammatory cytokines induced FTMT and VEGF expression, while NF-κB inhibition significantly reduced FTMT expression. VEGF protein and mRNA expression were significantly increased in FTMT-silenced ARPE-19 cells. Using an in vitro angiogenesis assay with endothelial cells, we showed that conditioned media from FTMT-overexpressing cells had significant antiangiogenic effects. Collectively, our findings indicate that increased levels of FTMT inhibit angiogenesis, possibly by reducing levels of VEGF and increasing PEDF expression. The cellular models developed can be used to investigate if increased FTMT may be protective in angiogenic diseases, such as AMD.

Neddylation inhibitor, MLN4924 suppresses angiogenesis in huvecs and solid cancers: in vitro and in vivo study

Cullin-RING E3 ligases are involved in the ubiquitination of substrates that regulate important biological processes and are a potential therapeutic target in many types of cancer. MLN4924, a small molecule of NEDD8-activating enzyme inhibitor, inactivates CRL by blocking cullin neddylation and has been reported to elicit anti-tumor effect. In this study, In this study, we aimed to investigate the effects of MLN4924 on angiogenesis in human umbilical vascular endothelial cells (HUVECs) and four types of cancer cells. Our results showed that MLN4924 inhibits cell viability and induced apoptosis in HUVECs in a dose-dependent manner. MLN4924 inhibits proliferation and interferes with the cell cycle checkpoint regulators, p21, p27, and phospho-histone H3. Vascular endothelial growth factor (VEGF) treatment increased the level of UBC12 in HUVECs, indicating that neddylation pathway is involved in VEGF-activated angiogenesis. MLN4924 decreased VEGF-activated cell proliferation via neddylation inhibition. MLN4924 inhibited VEGF-activated cell migration, capillary tube formation and VEGF-mediated Erk1/2 activation in HUVECs. We also examined antitumor effect of MLN4924 using xenograft SCID mouse models of four different types of cancer cells. The in vivo results showed MLN4924 inhibited tumor growth in all four types of cancers with decreasing CD31 expression in xenograft tumor. In conclusion, MLN4924 inhibited viability, migration, and VEGF-promoted angiogenic activity in HUVECs; consistently, MLN4924 inhibited tumor growth in four types of cancers with suppression of angiogenesis. These findings provide evidence to develop therapeutic strategy for cancer treatment through anti-angiogenesis through neddylation inhibition.