KSP inhibitor SB743921 inhibits growth and induces apoptosis of breast cancer cells by regulating p53, Bcl-2, and DTL

DTL promotes head and neck squamous cell carcinoma progression by mediating the degradation of ARGLU1 to regulate the Notch signaling pathway

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, with a high incidence in squamous epithelium. The E3 ubiquitin ligase DTL is a component of the CRL4A complex and is widely involved in tumor progression. We aimed to analyze the role of DTL in HNSCC and to explore its mechanism of action. Through clinical analysis, we found that DTL is upregulated in HNSCC tissues and is associated with the tumor microenvironment and poor survival in patients. Through gain-of-function and loss-of-function assays, we showed that DTL promotes cell proliferation and migration in vitro and tumor growth in vivo. Mass spectrometry analysis and immunoprecipitation assays showed that DTL interacts with ARGLU1 to promote K11-linked ubiquitination-mediated degradation of ARGLU1, thereby promoting the activation of the CSL-dependent Notch signaling pathway. Furthermore, siARGLU1 blocks the inhibitory effects of DTL knockdown on HNSCC cells. In this study, we showed that DTL promotes HNSCC progression through K11-linked ubiquitination of ARGLU1 to activate the CSL-dependent Notch pathway. These findings identify a promising therapeutic target for HNSCC.

Osteopontin regulates the growth and invasion of liver cancer cells via DTL

Osteopontin (OPN), a secreted phosphoglycoprotein, has important roles in tumor growth, invasion and metastasis in numerous types of cancers. Denticleless E3 ubiquitin protein ligase homolog (DTL), one of the CUL4-DDB1-associated factors (DCAFs), has also been associated with the invasion and metastasis of cancer cells. In the present study, OPN was found to induce DTL expression in liver cancer cells, and the results obtained using luciferase activity assays demonstrated that OPN could transcriptionally activate DTL expression in liver cancer cells. Furthermore, the results of the present study demonstrated that OPN could increase the expression of DTL via PI3K/AKT signaling. In conclusion, the present study demonstrated that OPN, as an extracellular matrix protein, is able to promote the growth and invasion of liver cancer cells through stimulation of the expression of DTL via the PI3K/AKT signaling pathway.

Inducing Mitotic Catastrophe as a Therapeutic Approach to Improve Outcomes in Ewing Sarcoma

Ewing sarcoma (EWS) is an aggressive pediatric malignancy of the bone and soft tissues in need of novel therapeutic options. To identify potential therapeutic targets, we focused on essential biological pathways that are upregulated by EWS-FLI1, the primary oncogenic driver of EWS, including mitotic proteins such as Aurora kinase A (AURKA) and kinesin family member 15 (KIF15) and its binding partner, targeting protein for Xklp2 (TPX2). KIF15/TPX2 cooperates with KIF11, a key mitotic kinesin essential for mitotic spindle orientation. Given the lack of clinical-grade KIF15/TPX2 inhibitors, we chose to target KIF11 (using SB-743921) in combination with AURKA (using VIC-1911) given that phosphorylation of KIF15S1169 by Aurora A is required for its targeting to the spindle. In vitro, the drug combination demonstrated strong synergy (Bliss score ≥ 10) at nanomolar doses. Colony formation assay revealed significant reduction in plating efficiency (1-3%) and increased percentage accumulation of cells in the G2/M phase with the combination treatment (45-52%) upon cell cycle analysis, indicating mitotic arrest. In vivo studies in EWS xenograft mouse models showed significant tumor reduction and overall effectiveness: drug combination vs. vehicle control (p ≤ 0.01), SB-743921 (p ≤ 0.01) and VIC-1911 (p ≤ 0.05). Kaplan-Meier curves demonstrated superior overall survival with the combination compared to vehicle or monotherapy arms (p ≤ 0.0001).

Role of motor proteins in human cancers

Motor proteins include several protein families (Kinesin, Dynein and Myosin) responsible for intracellular transport, intercellular communication, among other functions. In cancer cells, motor proteins along with microtubules (MT) and other tubulin and actin structures, are crucial for cell proliferation and invasion. The cBioPortal platform for Cancer Genomics database was queried for solid cancers in a combined cohort of 9204 patients with complete cancer genomics data. To assess the importance of motor proteins in cancer, copy number alterations (CNAs) and survival rates were analyzed in the combined dataset. Kinesin, Dynein, and Myosin families showed CNAs in 47%, 49%, and 57 % of patients, respectively, in at least one of their members. Survival analysis showed that CNAs in Kinesin and Dynein, families' genes in the same patients were significantly correlated to decreased overall survival. These results added more evidence to previous literature highlighting the importance of motor proteins as a target in cancer therapy. Kinesin inhibitors could act by several mechanisms such as inhibiting spindle assembly or centrosome separation during mitosis, leading to cell cycle arrest and eventually apoptosis. Dynein inhibitors modulate Dynein's activity and MT binding, inhibiting cell proliferation and invasion. Myosin inhibitors act by stabilizing MT, inducing cell cycle arrest and inhibiting invasiveness. Increasing the specificity of motor proteins targeting drugs could improve cancer therapy and patient survival.

DrDimont: explainable drug response prediction from differential analysis of multi-omics networks

MOTIVATION

While it has been well established that drugs affect and help patients differently, personalized drug response predictions remain challenging. Solutions based on single omics measurements have been proposed, and networks provide means to incorporate molecular interactions into reasoning. However, how to integrate the wealth of information contained in multiple omics layers still poses a complex problem.

RESULTS

We present DrDimont, Drug response prediction from Differential analysis of multi-omics networks. It allows for comparative conclusions between two conditions and translates them into differential drug response predictions. DrDimont focuses on molecular interactions. It establishes condition-specific networks from correlation within an omics layer that are then reduced and combined into heterogeneous, multi-omics molecular networks. A novel semi-local, path-based integration step ensures integrative conclusions. Differential predictions are derived from comparing the condition-specific integrated networks. DrDimont's predictions are explainable, i.e. molecular differences that are the source of high differential drug scores can be retrieved. We predict differential drug response in breast cancer using transcriptomics, proteomics, phosphosite and metabolomics measurements and contrast estrogen receptor positive and receptor negative patients. DrDimont performs better than drug prediction based on differential protein expression or PageRank when evaluating it on ground truth data from cancer cell lines. We find proteomic and phosphosite layers to carry most information for distinguishing drug response.

AVAILABILITY AND IMPLEMENTATION

DrDimont is available on CRAN: https://cran.r-project.org/package=DrDimont.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

A PARP1-related prognostic signature constructing and PARP-1 inhibitors screening for glioma

The current standard treatments of glioma include surgical resection, supplemented with radiotherapy and chemotherapy, but the prognosis is poor. PARP-1 (Poly ADP-ribose polymerase 1) is a hot spot for cancer-targeted therapy and was reported to be significantly elevated in glioma. In this study, we analyzed the role of PARP-1 in DNA damage repair, constructed a PARP1-related DNA-repair prognostic signature (DPS), and screened targeted drugs for glioma. RNA-seq data of 639 glioma samples were downloaded from the GEO (Gene Expression Omnibus) database and divided into PARP1_H and PARP1_L according to the front and rear thirds of the expression level of PARP-1. First, we systematically analyzed the influence of PARP-1 on DNA damage repair, prognosis, and chemoradiotherapy sensitization of glioma. All glioma patients and patients with radiotherapy or chemotherapy had a better prognosis in PARP1_L than in PARP1_H. Next, differentially expressed DNA-repair related genes (DEGs) were identified between PARP1_H and PARP1_L by LASSO (Least Absolute Shrinkage and Selection Operator) Cox analysis and applied for constructing DPS. Based on the four-gene DPS, we then developed a new nomogram to assess overall survival in glioma patients. Additionally, PARP-1 was proved an effective target for glioma therapy. So, a series of computer-aided techniques, including Discovery Studio 4.5, Schrodinger, and PyMol, were applied for the virtual screening of favorable PARP-1 inhibitors. In conclusion, this study investigated the effect of PARP-1 on glioma prognosis and the sensitization effect of radiotherapy and chemotherapy, established a novel nomogram to evaluate the overall survival of glioma patients, and further explored targeted therapy for glioma.

Identification of subgroups along the glycolysis-cholesterol synthesis axis and the development of an associated prognostic risk model

BACKGROUND

Skin cutaneous melanoma (SKCM) is one of the most highly prevalent and complicated malignancies. Glycolysis and cholesterogenesis pathways both play important roles in cancer metabolic adaptations. The main aims of this study are to subtype SKCM based on glycolytic and cholesterogenic genes and to build a clinical outcome predictive algorithm based on the subtypes.

METHODS

A dataset with 471 SKCM specimens was downloaded from The Cancer Genome Atlas (TCGA) database. We extracted and clustered genes from the Molecular Signatures Database v7.2 and acquired co-expressed glycolytic and cholesterogenic genes. We then subtyped the SKCM samples and validated the efficacy of subtypes with respect to simple nucleotide variations (SNVs), copy number variation (CNV), patients' survival statuses, tumor microenvironment, and proliferation scores. We also constructed a risk score model based on metabolic subclassification and verified the model using validating datasets. Finally, we explored potential drugs for high-risk SKCM patients.

RESULTS

SKCM patients were divided into four subtype groups: glycolytic, cholesterogenic, mixed, and quiescent subgroups. The glycolytic subtype had the worst prognosis and MGAM SNV extent. Compared with the cholesterogenic subgroup, the glycolytic subgroup had higher rates of DDR2 and TPR CNV and higher proliferation scores and MK167 expression levels, but a lower tumor purity proportion. We constructed a forty-four-gene predictive signature and identified MST-321, SB-743921, Neuronal Differentiation Inducer III, romidepsin, vindesine, and YM-155 as high-sensitive drugs for high-risk SKCM patients.

CONCLUSIONS

Subtyping SKCM patients via glycolytic and cholesterogenic genes was effective, and patients in the glycolytic-gene enriched group were found to have the worst outcome. A robust prognostic algorithm was developed to enhance clinical decisions in relation to drug administration.

Identification of novel compounds against Tat-mediated human immunodeficiency virus-1 transcription by high-throughput functional screening assay

Trans-activator (Tat)-mediated human immunodeficiency virus type 1 (HIV-1) transcription is essential for the replication of HIV-1 and is considered a potent therapeutic target for HIV-1 inhibition. In this study, the Library of Pharmacologically Active Compounds (LOPAC¹²⁸⁰) was screened using our dual-reporter screening system for repositioning as Tat-inhibitory compounds. Consequently, two compounds were found to be potent, with low cytotoxicity. Of these two compounds, Roscovitine (CYC202) is already known to be a Tat inhibitor, while gemcitabine has been newly identified as an inhibitor of Tat-mediated transcription linked to viral production and replication. In an additional screening using the ribonucleoside analogues of gemcitabine, two analogues (2'-C-methylcytidine and 3-deazauridine) showed a specific Tat-inhibitory effect linked to their anti-HIV-1 activity. Interestingly, these compounds did not affect Tat protein directly, while the mechanism underlying their inhibition of Tat-mediated transcription was linked to pyrimidine biosynthesis, rather than to alteration of the dNTP pool, influenced by the inhibition of ribonucleotide reductase. Taken together, the proposed functional screening system is a useful tool for the identification of inhibitors of Tat-mediated HIV-1 transcription from among a large number of compounds, and the inhibitory effect of HIV-1 transcription by gemcitabine and its analogues may suggest a strategy for developing a new class of therapeutic anti-HIV drugs.

Growth arrest and apoptosis induced by kinesin Eg5 inhibitor K858 and by its 1,3,4-thiadiazoline analogue in tumor cells

Tumors are complex and heterogeneous but, despite this, they share the ability to proliferate continuously, irrespective of the presence of growth signals, leading to a higher fraction of actively growing and dividing cells compared with normal tissues. For this reason, the cytotoxic antimitotic treatments remain an important clinical tool for tumors. Among these drugs, antitubulin compounds constitute one of the most effective anticancer chemotherapies; however, they cause dose-limiting side effects. Therefore, it is still necessary to develop compounds with new targets and new mechanisms of action to reduce side effects or chemoresistance. Mitosis-specific kinesin Eg5 can represent an attractive target for discovering such new anticancer agents because its role is fundamental in mitotic progression. Therefore, we analyzed the effects induced by an inhibitor of kinesin Eg5, K858, and by its 1,3,4-thiadiazoline analogue on human melanoma and prostate cancer cell lines. We found that both compounds have an antiproliferative effect, induce apoptosis, and can determine a downmodulation of survivin.

High kinesin family member 11 expression predicts poor prognosis in patients with clear cell renal cell carcinoma

Aims

Kinesin family member 11 (Kif11) is a member of the kinesin family motor proteins, which is associated with spindle formation and tumour genesis. In this study, we investigated the relationship between Kif11 expression and clear cell renal cell carcinoma (CCRCC) development.

Methods

The relationship between Kif11 expression and CCRCC development was analysed by quantitative real-time (qRT)-PCR analyses, and tissue immunohistochemistry. The prognostic significance of Kif11 expression was explored by univariable and multivariable survival analyses of 143 included patients. Furthermore, SB743921 was used as a specific Kif11 inhibitor to treat 786-O cells with the epithelial to mesenchymal transition (EMT) process analysed by qRT-PCR, and cell survival rates analysed with Annexin V-FITC/PI staining followed by flow cytometric analyses. Disease-free survival curves of Kif11 with different cancers and the relationships between Kif11 and the von Hippel-Lindau disease tumour suppressor gene (VHL), and proliferating cell nuclear antigen (PCNA) in kidney cancer were further analysed using the GEPIA database.

Results

The levels of Kif11 mRNA were significantly higher in CCRCC tissues compared with corresponding non-cancerous tissues. The results of immunohistochemistry demonstrated that the expression of Kif11 protein was significantly associated with clinicopathologial parameters, including nuclear grade and TNM stage. The Kaplan-Meier survival curve indicated that high Kif11 expression, nuclear grade and TNM stage were independent factors to predict poor prognosis in patients with CCRCC. In addition, inhibition of Kif11 expression by SB743921 suppressed cell proliferation, migration and the EMT process with increased apoptosis rate.

Conclusions

These results combined with bioinformation analyses suggest that high Kif11 expression was associated with unfavourable prognosis in CCRCC and could be used as a potential prognostic marker in the clinical diagnosis of CCRCC.

Meiotic arrest and spindle defects are associated with altered KIF11 expression in porcine oocytes

Kinesin superfamily proteins (KIFs) act as molecular motors and are involved in material transport along microtubules to maintain normal cellular functions. KIF11 (also named kinesin-5, Eg5, and KSP) is a plus-end-directed homotetrameric kinesin that regulates spindle formation for actuate chromosomal separation during mitosis. However, the roles of KIF11 in meiosis are still unclear. In this study, we investigated the regulatory functions of KIF11 during porcine oocyte maturation. The results indicated that KIF11 was expressed in different stages during porcine oocyte meiosis. Inhibition of KIF11 activity led to the failure of the first polar body extrusion, and we found that cell cycle progression was disturbed, which was confirmed by the decreased Cdc2 expression. Furthermore, inhibition of KIF11 resulted in decreased tubulin acetylation and caused sequential disruption of the spindle assembly and chromosome alignment. We also found that in postovulatory aging porcine oocytes, the KIF11 expression was altered, indicating that KIF11 was involved with aging-induced spindle disorganization. In summary, our results showed that KIF11 regulated the cell cycle and tubulin acetylation related spindle formation in porcine oocyte meiosis. Environ. Mol. Mutagen. 59:805-812, 2018. © 2018 Wiley Periodicals, Inc.

Kinesin superfamily: roles in breast cancer, patient prognosis and therapeutics

Breast cancer pathobiology is known to be influenced by the differential expression of a group of proteins called the kinesin superfamily (KIFs), which is instrumental in the intracellular transport of chromosomes along microtubules during mitosis. During cellular division, kinesins are strictly regulated through temporal synthesis so that they are present only when needed. However, their misregulation may contribute to uncontrolled cell growth owing to premature sister chromatid separation, highlighting their importance in cancer. This review covers the functions of kinesins in normal and breast cancer cells, the use of kinesins for breast cancer patient prognosis, and the targeting of these molecules for therapeutics. A better understanding of KIF proteins may be pivotal to improved disease outcomes for breast cancer patients.