Kinesins and cancer

WZ-3146 acts as a novel small molecule inhibitor of KIF4A to inhibit glioma progression by inducing apoptosis

BACKGROUND

Glioma is considered the most common primary malignant tumor of the central nervous system. Although traditional treatments have not achieved satisfactory outcomes, recently, targeted therapies for glioma have shown promising efficacy. However, due to the single-target nature of targeted therapy, traditional targeted therapies are ineffective; thus, novel therapeutic targets are urgently needed.

METHODS

The gene expression data for glioma patients were derived from the GEO (GSE4290, GSE50161), TCGA and CGGA databases. Next, the upregulated genes obtained from the above databases were cross-analyzed, finally, 10 overlapping genes (BIRC5, FOXM1, EZH2, CDK1, KIF11, KIF4A, NDC80, PBK, RRM2, and TOP2A) were ultimately screened and only KIF4A expression has the strongest correlation with clinical characteristics in glioma patients. Futher, the TCGA and CGGA database were utilized to explore the correlation of KIF4A expression with glioma prognosis. Then, qRT-PCR and Western blot was used to detect the KIF4A mRNA and protein expression level in glioma cells, respectively. And WZ-3146, the small molecule inhibitor targeting KIF4A, were screened by Cmap analysis. Subsequently, the effect of KIF4A knockdown or WZ-3146 treatment on glioma was measured by the MTT, EdU, Colony formation assay and Transwell assay. Ultimately, GSEA enrichment analysis was performed to find that the apoptotic pathway could be regulated by KIF4A in glioma, in addition, the effect of WZ-3146 on glioma apoptosis was detected by flow cytometry and Western blot.

RESULTS

In the present study, we confirmed that KIF4A is abnormally overexpressed in glioma. In addition, KIF4A overexpression is a key indicator of glioma prognosis; moreover, suppressing KIF4A expression can inhibit glioma progression. We also discovered that WZ-3146, a small molecule inhibitor of KIF4A, can induce apoptosis in glioma cells and exhibit antiglioma effects.

CONCLUSION

In conclusion, these observations demonstrated that targeting KIF4A can inhibit glioma progression. With further research, WZ-3146, a small molecule inhibitor of KIF4A, could be combined with other molecular targeted drugs to cooperatively inhibit glioma progression.

Eg5 and Diseases: From the Well-Known Role in Cancer to the Less-Known Activity in Noncancerous Pathological Conditions

Eg5 is a protein encoded by KIF11 gene and is primarily involved in correct mitotic cell division. It is also involved in nonmitotic processes such as polypeptide synthesis, protein transport, and angiogenesis. The scientific literature sheds light on the ubiquitous functions of KIF11 and its involvement in the onset and progression of different pathologies. This review focuses attention on two main points: (1) the correlation between Eg5 and cancer and (2) the involvement of Eg5 in noncancerous conditions. Regarding the first point, several tumors revealed an overexpression of this kinesin, thus pushing to look for new Eg5 inhibitors for clinical practice. In addition, the evaluation of Eg5 expression represents a crucial step, as its overexpression could predict a poor prognosis for cancer patients. Referring to the second point, in specific pathological conditions, the reduced activity of Eg5 can be one of the causes of pathological onset. This is the case of Alzheimer's disease (AD), in which Aβ and Tau work as Eg5 inhibitors, or in acquired immune deficiency syndrome (AIDS), in which Tat-mediated Eg5 determines the loss of CD4+ T-lymphocytes. Reduced Eg5 activity, due to mutations of KIF11 gene, is also responsible for pathological conditions such as microcephaly with or without chorioretinopathy, lymphedema, or intellectual disability (MCLRI) and familial exudative vitreous retinopathy (FEVR). In conclusion, this review highlights the double impact that overexpression or loss of function of Eg5 could have in the onset and progression of different pathological situations. This emphasizes, on one hand, a possible role of Eg5 as a potential biomarker and new target in cancer and, on the other hand, the promotion of Eg5 expression/activity as a new therapeutic strategy in different noncancerous diseases.

Binding patterns of inhibitors to different pockets of kinesin Eg5

The kinesin-5 family member, Eg5, plays very important role in the mitosis. As a mitotic protein, Eg5 is the target of various mitotic inhibitors. There are two targeting pockets in the motor domain of Eg5, which locates in the α2/L5/α3 region and the α4/α6 region respectively. We investigated the interactions between the different inhibitors and the two binding pockets of Eg5 by using all-atom molecular dynamics method. Combined the conformational analysis with the free-energy calculation, the binding patterns of inhibitors to the two binding pockets are shown. The α2/L5/α3 pocket can be divided into 4 regions. The structures and binding conformations of inhibitors in region 1 and 2 are highly conserved. The shape of α4/α6 pocket is alterable. The space of this pocket in ADP-binding state of Eg5 is larger than that in ADP·Pi-binding state due to the limitation of a hydrogen bond formed in the ADP·Pi-binding state. The results of this investigation provide the structural basis of the inhibitor-Eg5 interaction and offer a reference for the Eg5-targeted drug design.

Antiparallel microtubule bundling supports KIF15-driven mitotic spindle assembly

The spindle is a bipolar microtubule-based machine that is crucial for accurate chromosome segregation. Spindle bipolarity is generated by Eg5 (a kinesin-5), a conserved motor that drives spindle assembly by localizing to and sliding apart antiparallel microtubules. In the presence of Eg5 inhibitors (K5Is), KIF15 (a kinesin-12) can promote spindle assembly, resulting in K5I-resistant cells (KIRCs). However, KIF15 is a less potent motor than Eg5, suggesting that other factors may contribute to spindle formation in KIRCs. Protein Regulator of Cytokinesis 1 (PRC1) preferentially bundles antiparallel microtubules, and we previously showed that PRC1 promotes KIF15-microtubule binding, leading us to hypothesize that PRC1 may enhance KIF15 activity in KIRCs. Here, we demonstrate that: 1) loss of PRC1 in KIRCs decreases spindle bipolarity, 2) overexpression of PRC1 increases spindle formation efficiency in KIRCs, 3) overexpression of PRC1 protects K5I naïve cells against the K5I S-trityl-L-cysteine (STLC), and 4) PRC1 overexpression promotes the establishment of K5I resistance. These effects are not fully reproduced by a TPX2, a microtubule bundler with no known preference for microtubule orientation. These results suggest a model wherein PRC1-mediated bundling of microtubules creates a more favorable microtubule architecture for KIF15-driven mitotic spindle assembly in the context of Eg5 inhibition.

Cancer on motors: How kinesins drive prostate cancer progression?

Prostate cancer causes numerous male deaths annually. Although great progress has been made in the diagnosis and treatment of prostate cancer during the past several decades, much about this disease remains unknown, especially its pathobiology. The kinesin superfamily is a pivotal group of motor proteins, that contains a microtubule-based motor domain and features an adenosine triphosphatase activity and motility characteristics. Large-scale sequencing analyses based on clinical samples and animal models have shown that several members of the kinesin family are dysregulated in prostate cancer. Abnormal expression of kinesins could be linked to uncontrolled cell growth, inhibited apoptosis and increased metastasis ability. Additionally, kinesins may be implicated in chemotherapy resistance and escape immunologic cytotoxicity, which creates a barrier to cancer treatment. Here we cover the recent advances in understanding how kinesins may drive prostate cancer progression and how targeting their function may be a therapeutic strategy. A better understanding of kinesins in prostate cancer tumorigenesis may be pivotal for improving disease outcomes in prostate cancer patients.

Neurons dispose of hyperactive kinesin into glial cells for clearance

Microtubule-based kinesin motor proteins are crucial for intracellular transport, but their hyperactivation can be detrimental for cellular functions. This study investigated the impact of a constitutively active ciliary kinesin mutant, OSM-3CA, on sensory cilia in C. elegans. Surprisingly, we found that OSM-3CA was absent from cilia but underwent disposal through membrane abscission at the tips of aberrant neurites. Neighboring glial cells engulf and eliminate the released OSM-3CA, a process that depends on the engulfment receptor CED-1. Through genetic suppressor screens, we identified intragenic mutations in the OSM-3CA motor domain and mutations inhibiting the ciliary kinase DYF-5, both of which restored normal cilia in OSM-3CA-expressing animals. We showed that conformational changes in OSM-3CA prevent its entry into cilia, and OSM-3CA disposal requires its hyperactivity. Finally, we provide evidence that neurons also dispose of hyperactive kinesin-1 resulting from a clinic variant associated with amyotrophic lateral sclerosis, suggesting a widespread mechanism for regulating hyperactive kinesins.

Analyzing the expression and clinical significance of CENPE in gastric cancer

BACKGROUND

Gastric cancer (GC) is a prevalent type of malignant gastrointestinal tumor. Many studies have shown that CENPE acts as an oncogene in some cancers. However, its expression level and clinical value in GC are not clear.

METHODS

Obtaining clinical data information on gastric adenocarcinoma from TCGA and GEO databases. The gene expression profiling interaction analysis (GEPIA) was used to evaluate the relationship between prognosis and CENPE expression in gastric cancer patients. Utilizing the UALCAN platform, the correlation between CENPE expression and clinical parameters was examined. Functions and signaling pathways of CENPE were analyzed using the Gene Ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA). The association between immunological infiltrating cells and CENPE expression was examined using TIMER2.0. Validation was performed by real-time quantitative PCR (qPT-PCR) and immunohistochemical analysis.

RESULTS

According to the analysis of the GEPIA database, the expression of CENPE is increased in gastric cancer tissues compared to normal tissues. It was also found to have an important relationship with the prognosis of the patient (p<0.05). The prognosis was worse and overall survival was lower in individuals with increased expression of CENPE. In line with the findings of the GEPIA, real-time fluorescence quantitative PCR (qPT-PCR) confirmed that CENPE was overexpressed in gastric cancer cells. Furthermore, It was discovered that H. pylori infection status and tumor grade were related to CENPE expression. Enrichment analysis revealed that CENPE expression was linked to multiple biological functions and tumor-associated pathways. CENPE expression also correlated with immune-infiltrating cells in the gastric cancer microenvironment and was positively connected to NK cells and mast cells. According to immunohistochemical examination, paracancerous tissues had minimal expression of CENPE, but gastric cancer showed significant expression of the protein.

CONCLUSIONS

According to our findings, CENPE is substantially expressed in GC and may perhaps contribute to its growth. CENPE might be a target for gastric cancer therapy and a predictor of a bad prognosis.

High Expression of KIFC1 in Glioma Correlates with Poor Prognosis

OBJECTIVE

Kinesin family member C1 (KIFC1), a non-essential kinesin-like motor protein, has been found to serve a crucial role in supernumerary centrosome clustering and the progression of several human cancer types. However, the role of KIFC1 in glioma has been rarely reported. Thus, the present study aimed to investigate the role of KIFC1 in glioma progression.

METHODS

Online bioinformatics analysis was performed to determine the association between KIFC1 expression and clinical outcomes in glioma. Immunohistochemical staining was conducted to analyze the expression levels of KIFC1 in glioma and normal brain tissues. Furthermore, KIFC1 expression was knocked in the glioma cell lines, U251 and U87MG, and the functional roles of KIFC1 in cell proliferation, invasion and migration were analyzed using cell multiplication, wound healing and Transwell invasion assays, respectively. The autophagic flux and expression levels matrix metalloproteinase-2 (MMP2) were also determined using imaging flow cytometry, western blotting and a gelation zymography assay.

RESULTS

The results revealed that KIFC1 expression levels were significantly upregulated in glioma tissues compared with normal brain tissues, and the expression levels were positively associated with tumor grade. Patients with glioma with low KIFC1 expression levels had a more favorable prognosis compared with patients with high KIFC1 expression levels. In vitro, KIFC1 knockdown not only inhibited the proliferation, migration and invasion of glioma cells, but also increased the autophagic flux and downregulated the expression levels of MMP2.

CONCLUSION

Upregulation of KIFC1 expression may promote glioma progression and KIFC1 may serve as a potential prognostic biomarker and possible therapeutic target for glioma.

Loss of EIF4G2 mediates aggressiveness in distinct human endometrial cancer subpopulations with poor survival outcome in patients

The non-canonical translation initiation factor EIF4G2 plays essential roles in cellular stress responses via translation of selective mRNA cohorts. Currently there is limited and conflicting information regarding its involvement in cancer development and progression. Here we assessed its role in endometrial cancer (EC), in a cohort of 280 EC patients across different types, grades, and stages, and found that low EIF4G2 expression highly correlated with poor overall- and recurrence-free survival in Grade 2 EC patients, monitored over a period of up to 12 years. To establish a causative connection between low EIF4G2 expression and cancer progression, we stably knocked-down EIF4G2 in two human EC cell lines in parallel. EIF4G2 depletion resulted in increased resistance to conventional therapies and increased the prevalence of molecular markers for aggressive cell subsets, altering their transcriptional and proteomic landscapes. Prominent among the proteins with decreased abundance were Kinesin-1 motor proteins, KIF5B and KLC1, 2, 3. Multiplexed imaging of the EC patient tumor cohort showed a correlation between decreased expression of the kinesin proteins, and poor survival in patients with tumors of certain grades and stages. These findings reveal potential novel biomarkers for Grade 2 EC with ramifications for patient stratification and therapeutic interventions.

BUB1/KIF14 complex promotes anaplastic thyroid carcinoma progression by inducing chromosome instability

Chromosome instability (CIN) is a common contributor driving the formation and progression of anaplastic thyroid cancer (ATC), but its mechanism remains unclear. The BUB1 mitotic checkpoint serine/threonine kinase (BUB1) is responsible for the alignment of mitotic chromosomes, which has not been thoroughly studied in ATC. Our research demonstrated that BUB1 was remarkably upregulated and closely related to worse progression-free survival. Knockdown of BUB1 attenuated cell viability, invasion, migration and induced cell cycle arrests, whereas overexpression of BUB1 promoted the cell cycle progression of papillary thyroid cancer cells. BUB1 knockdown remarkably repressed tumour growth and tumour formation of nude mice with ATC xenografts and suppressed tumour metastasis in a zebrafish xenograft model. Inhibition of BUB1 by its inhibitor BAY-1816032 also exhibited considerable anti-tumour activity. Further studies showed that enforced expression of BUB1 evoked CIN in ATC cells. BUB1 induced CIN through phosphorylation of KIF14 at serine1292 (Ser1292 ). Overexpression of the KIF14ΔSer1292 mutant was unable to facilitate the aggressiveness of ATC cells when compared with that of the wild type. Collectively, these findings demonstrate that the BUB1/KIF14 complex drives the aggressiveness of ATC by inducing CIN.

Kinesin-7 CENP-E in tumorigenesis: Chromosome instability, spindle assembly checkpoint, and applications

Kinesin motors are a large family of molecular motors that walk along microtubules to fulfill many roles in intracellular transport, microtubule organization, and chromosome alignment. Kinesin-7 CENP-E (Centromere protein E) is a chromosome scaffold-associated protein that is located in the corona layer of centromeres, which participates in kinetochore-microtubule attachment, chromosome alignment, and spindle assembly checkpoint. Over the past 3 decades, CENP-E has attracted great interest as a promising new mitotic target for cancer therapy and drug development. In this review, we describe expression patterns of CENP-E in multiple tumors and highlight the functions of CENP-E in cancer cell proliferation. We summarize recent advances in structural domains, roles, and functions of CENP-E in cell division. Notably, we describe the dual functions of CENP-E in inhibiting and promoting tumorigenesis. We summarize the mechanisms by which CENP-E affects tumorigenesis through chromosome instability and spindle assembly checkpoints. Finally, we overview and summarize the CENP-E-specific inhibitors, mechanisms of drug resistances and their applications.

The role of kinesin family members in hepatobiliary carcinomas: from bench to bedside

As a major component of the digestive system malignancies, tumors originating from the hepatic and biliary ducts seriously endanger public health. The kinesins (KIFs) are molecular motors that enable the microtubule-dependent intracellular trafficking necessary for mitosis and meiosis. Normally, the stability of KIFs is essential to maintain cell proliferation and genetic homeostasis. However, aberrant KIFs activity may destroy this dynamic stability, leading to uncontrolled cell division and tumor initiation. In this work, we have made an integral summarization of the specific roles of KIFs in hepatocellular and biliary duct carcinogenesis, referring to aberrant signal transduction and the potential for prognostic evaluation. Additionally, current clinical applications of KIFs-targeted inhibitors have also been discussed, including their efficacy advantages, relationship with drug sensitivity or resistance, the feasibility of combination chemotherapy or other targeted agents, as well as the corresponding clinical trials. In conclusion, the abnormally activated KIFs participate in the regulation of tumor progression via a diverse range of mechanisms and are closely associated with tumor prognosis. Meanwhile, KIFs-aimed inhibitors also carry out a promising tumor-targeted therapeutic strategy that deserves to be further investigated in hepatobiliary carcinoma (HBC).

KIF4A promotes epithelial-mesenchymal transition by activating the TGF-β/SMAD signaling pathway in glioma cells

Gliomas are the most prevalent type of primary brain tumor, with poor prognosis reported in patients with high-grade glioma. Kinesin family member 4 A (KIF4A) stimulates the proliferation, migration, and invasion of tumor cells. However, its function in gliomas has not been clearly established. Therefore, this study aimed to investigate the effects of KIF4A on the epithelial-mesenchymal transition and invasion of glioma cells. We searched The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases to identify KIF4A-related signaling pathways and downstream genes. We further validated them using western blotting, transwell migration and invasion, wound-healing scratch, and dual-luciferase reporter assays in U251 and U87 human glioblastoma cells. Our analysis of the Cancer Genome Atlas and Chinese Glioma Genome Atlas data showed elevated KIF4A expression in patients with gliomas and was associated with clinical grade. Here, KIF4A overexpression promoted the migration, invasion, and proliferation of glioma cells, whereas KIF4A knockdown showed contrasting results. Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) analyses demonstrated that KIF4A positively controls TGF-β/SMAD signaling in glioma cells. Additionally, genetic correlation analysis revealed that KIF4A transcriptionally controls benzimidazoles-1 expression in glioma cells. KIF4A promotes the epithelial-mesenchymal transition by regulating the TGF-β/SMAD signaling pathway via benzimidazoles-1 in glioma cells.

Noncanonical interaction with microtubules via the N-terminal nonmotor domain is critical for the functions of a bidirectional kinesin

Several kinesin-5 motors (kinesin-5s) exhibit bidirectional motility. The mechanism of such motility remains unknown. Bidirectional kinesin-5s share a long N-terminal nonmotor domain (NTnmd), absent in exclusively plus-end-directed kinesins. Here, we combined in vivo, in vitro, and cryo-electron microscopy (cryo-EM) studies to examine the impact of NTnmd mutations on the motor functions of the bidirectional kinesin-5, Cin8. We found that NTnmd deletion mutants exhibited cell viability and spindle localization defects. Using cryo-EM, we examined the structure of a microtubule (MT)-bound motor domain of Cin8, containing part of its NTnmd. Modeling and molecular dynamic simulations based on the cryo-EM map suggested that the NTnmd of Cin8 interacts with the C-terminal tail of β-tubulin. In vitro experiments on subtilisin-treated MTs confirmed this notion. Last, we showed that NTnmd mutants are defective in plus-end-directed motility in single-molecule and antiparallel MT sliding assays. These findings demonstrate that the NTnmd, common to bidirectional kinesin-5s, is critical for their bidirectional motility and intracellular functions.

A plant flavonol and genetic suppressors rescue a pathogenic mutation associated with kinesin in neurons

KIF1A, a microtubule-based motor protein responsible for axonal transport, is linked to a group of neurological disorders known as KIF1A-associated neurological disorder (KAND). Current therapeutic options for KAND are limited. Here, we introduced the clinically relevant KIF1A(R11Q) variant into the Caenorhabditis elegans homolog UNC-104, resulting in uncoordinated animal behaviors. Through genetic suppressor screens, we identified intragenic mutations in UNC-104's motor domain that rescued synaptic vesicle localization and coordinated movement. We showed that two suppressor mutations partially recovered motor activity in vitro by counteracting the structural defect caused by R11Q at KIF1A's nucleotide-binding pocket. We found that supplementation with fisetin, a plant flavonol, improved KIF1A(R11Q) worms' movement and morphology. Notably, our biochemical and single-molecule assays revealed that fisetin directly restored the ATPase activity and processive movement of human KIF1A(R11Q) without affecting wild-type KIF1A. These findings suggest fisetin as a potential intervention for enhancing KIF1A(R11Q) activity and alleviating associated defects in KAND.

Regulation of ciliary homeostasis by intraflagellar transport-independent kinesins

Cilia are highly conserved eukaryotic organelles that protrude from the cell surface and are involved in sensory perception, motility, and signaling. Their proper assembly and function rely on the bidirectional intraflagellar transport (IFT) system, which involves motor proteins, including antegrade kinesins and retrograde dynein. Although the role of IFT-mediated transport in cilia has been extensively studied, recent research has highlighted the contribution of IFT-independent kinesins in ciliary processes. The coordinated activities and interplay between IFT kinesins and IFT-independent kinesins are crucial for maintaining ciliary homeostasis. In this comprehensive review, we aim to delve into the specific contributions and mechanisms of action of the IFT-independent kinesins in cilia. By shedding light on their involvement, we hope to gain a more holistic perspective on ciliogenesis and ciliopathies.

Small-molecule inhibition of kinesin KIF18A reveals a mitotic vulnerability enriched in chromosomally unstable cancers

Chromosomal instability (CIN) is a hallmark of cancer, caused by persistent errors in chromosome segregation during mitosis. Aggressive cancers like high-grade serous ovarian cancer (HGSOC) and triple-negative breast cancer (TNBC) have a high frequency of CIN and TP53 mutations. Here, we show that inhibitors of the KIF18A motor protein activate the mitotic checkpoint and selectively kill chromosomally unstable cancer cells. Sensitivity to KIF18A inhibition is enriched in TP53-mutant HGSOC and TNBC cell lines with CIN features, including in a subset of CCNE1-amplified, CDK4-CDK6-inhibitor-resistant and BRCA1-altered cell line models. Our KIF18A inhibitors have minimal detrimental effects on human bone marrow cells in culture, distinct from other anti-mitotic agents. In mice, inhibition of KIF18A leads to robust anti-cancer effects with tumor regression observed in human HGSOC and TNBC models at well-tolerated doses. Collectively, our results provide a rational therapeutic strategy for selective targeting of CIN cancers via KIF18A inhibition.

UHRF1 promotes spindle assembly and chromosome congression by catalyzing EG5 polyubiquitination

UHRF1 is an epigenetic coordinator bridging DNA methylation and histone modifications. Additionally, UHRF1 regulates DNA replication and cell cycle, and its deletion induces G1/S or G2/M cell cycle arrest. The roles of UHRF1 in the regulation of G2/M transition remain poorly understood. UHRF1 depletion caused chromosome misalignment, thereby inducing cell cycle arrest at mitotic metaphase, and these cells exhibited the defects of spindle geometry, prominently manifested as shorter spindles. Mechanistically, UHRF1 protein directly interacts with EG5, a kinesin motor protein, during mitosis. Furthermore, UHRF1 induced EG5 polyubiquitination at the site of K1034 and further promoted the interaction of EG5 with spindle assembly factor TPX2, thereby ensuring accurate EG5 distribution to the spindles during metaphase. Our study clarifies a novel UHRF1 function as a nuclear protein catalyzing EG5 polyubiquitination for proper spindle architecture and faithful genomic transmission, which is independent of its roles in epigenetic regulation and DNA damage repair inside the nucleus. These findings revealed a previously unknown mechanism of UHRF1 in controlling mitotic spindle architecture and chromosome behavior and provided mechanistic evidence for UHRF1 deletion-mediated G2/M arrest.

A nine-gene signature as prognostic biomarker in gastric cancer by bioinformatics analysis

PURPOSE

The prognosis of advanced gastric cancer (GC) remains poor. It is urgent and necessary to find suitable prognostic markers. miR-619-5p is highly expressed in GC. However, the value of miR-619-5p and its target genes as prognostic biomarkers of GC is unclear.

METHODS

RT-PCR was performed to verify the expression of miR-619-5p in GC cell lines and their exosomes. Western blotting and transmission electron microscope were used to identify exosomes. The target genes of miR-619-5p were predicted by RNA22 and TargetScan. The differentially expressed genes (DEGs) and prognosis-related genes (PRGs) were obtained using The Cancer Genome Atlas (TCGA) database. The DAVID database was used to analyse pathway enrichment and functional annotation of common target genes. The STRING database and Cytoscape software were used to screen key genes and visualize their functional modules. The survival analysis was conducted using TCGA and Kaplan-Meier Plotter (KMP) databases. Finally, a prognostic model was constructed on the foundation of the key genes to assess the reliability of the screening process.

RESULTS

The expression of miR-619-5p in GC cells and their exosomes was proved to be significantly higher than that in normal cell lines. There are 129 common target genes involved in 3 pathways and 28 functional annotations. Finally, nine key target genes of GC (BRCA1, RAD51, KIF11, ERCC6L, BRIP1, TIMELESS, CDC25A, CLSPN and NCAPG2) were identified, and a prognostic model was successfully constructed with a good predictive ability.

CONCLUSIONS

The model of 9-gene signature could effectively predict the prognosis of GC, and have great potential to be novel prognostic factors and therapeutic targets for patients with GC.

Dual inhibition of KIF11 and BCL2L1 induces apoptosis in lung adenocarcinoma cells

EGFR-mutant lung adenocarcinoma (LUAD) mostly depends on EGFR for survival and consequently responds well to EGFR inhibitors. However, resistance to the drugs develops almost universally during treatment. We previously demonstrated that EGFR-mutant LUAD cell lines, HCC827 and H1975, have subpopulations of cells, which we termed HCC827 GR2 and H1975 WR7 cells, that can thrive independently of EGFR signaling. These EGFR-independent EGFR-mutant cancer cells are difficult to treat because they lack sensitivity to EGFR inhibitors. Therefore, the development of novel strategies to target EGFR-independent EGFR-mutant LUAD is particularly important. We found that high expression of kinesin family member 11 (KIF11) correlated with poor survival in patients with LUAD. We also observed that KIF11 silencing caused cell cycle arrest at G2/M in HCC827 GR2 and H1975 WR7 cells. Furthermore, dual silencing of KIF11 plus BCL2L1, an anti-apoptotic BCL2 family member, in these two EGFR-independent sublines resulted in marked apoptosis levels. Dual inhibition of KIF11 plus BCL2L1 also induced apoptosis in HCC827 and H1975 parental cells and a KRAS-mutant LUAD cell line, H441. These findings collectively suggest that dual inhibition of KIF11 plus BCL2L1 may be a new approach for the treatment of LUAD.

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).

Kinesin Family Member B18 Is Related to Gastric Mucin Phenotype and Contributes to Gastric Cancer Progression by Regulating Epithelial-Mesenchymal Transition

INTRODUCTION

Gastric cancer (GC) remains a common health concern worldwide and is the third leading cause of death in Japan. It can be broadly classified into gastric and intestinal mucin phenotypes using immunohistochemistry. We previously reported numerous associations of kinesin family member (KIF) genes and mucin phenotypes with GC. However, no previous studies have reported on the importance of KIF18B in GC using immunostaining. Thus, in this study, we investigated the expression and functions of KIF18B, which is highly expressed in gastric mucin phenotype GC.

METHODS

We performed RNA-seq of gastric and intestinal mucin type GCs, and clinicopathological studies of the KIF18B we found were performed using 96 GC cases. We also performed functional analysis using GC-derived cell lines.

RESULT

RNA-seq showed the upregulation of matrisome-associated genes in gastric mucin phenotype GC and a high expression of KIF18B. KIF18B was detected in 52 of the 96 GC cases (54%) through immunohistochemistry. Low KIF18B expression was significantly associated with poor overall survival (p < 0.01). Other molecules that were significantly associated with KIF18B were MUC5AC and claudin 18; these were also significantly associated with the gastric mucin phenotype. KIF18B small interfering RNA (siRNA)-transfected GC cells showed greater growth and spheroid colony formation than the negative control siRNA-transfected cells. Furthermore, expression of snail family transcriptional repressor 1 and cadherin 2 was significantly increased and that of cadherin 1 was significantly decreased in KIF18B siRNA-transfected GC cells.

CONCLUSION

These findings not only suggest that KIF18B may be a useful prognostic marker, but also provide insight into the pathogenesis of the GC phenotype.

Forkhead box O6 (FoxO6) promotes cardiac pathological remodeling and dysfunction by activating Kif15-TGF-β1 under aggravated afterload

Pathological cardiac hypertrophy exhibits complex and abnormal gene expression patterns and progresses to heart failure. Forkhead box protein O6 (FoxO6) is a key transcription factor involved in many biological processes. This study aimed to explore the role of FoxO6 in cardiac hypertrophy. Three groups of mice were established: wild-type, FoxO6 knockout, and FoxO6-overexpressing. The mice received daily administration of angiotensin-II (Ang-II) or saline for 4 weeks, after which they were examined for cardiac hypertrophy, fibrosis, and function. Elevated cardiac expression of FoxO6 was observed in Ang-II-treated mice. FoxO6 deficiency attenuated contractile dysfunction and cardiac remodeling, including cardiomyocyte hypertrophy and fibroblast proliferation and differentiation. Conversely, FoxO6 overexpression aggravated the cardiomyopathy and heart dysfunction. Further studies identified kinesin family member 15 (Kif15) as downstream molecule of FoxO6. Kif15 inhibition attenuated the aggravating effect of FoxO6 overexpression. In vitro, FoxO6 overexpression increased Kif15 expression in cardiomyocytes and elevated the concentration of transforming growth factor-β1 (TGF-β1) in the medium where fibroblasts were grown, exhibiting increased proliferation and differentiation, while FoxO6 knockdown attenuated this effect. Cardiac-derived FoxO6 promoted pathological cardiac remodeling induced by aggravated afterload largely by activating the Kif15/TGF-β1 axis. This result further complements the mechanisms of communication among different cells in the heart, providing novel therapeutic targets for heart failure.

Design, Synthesis, and Evaluation of Biological Activity of Ferrocene-Ispinesib Hybrids: Impact of a Ferrocenyl Group on the Antiproliferative and Kinesin Spindle Protein Inhibitory Activity

With the aim to combine more than one biologically-active component in a single molecule, derivatives of ispinesib and its (S) analogue were prepared that featured ferrocenyl moieties or bulky organic substituents. Inspired by the strong kinesin spindle protein (KSP) inhibitory activity of ispinesib, the compounds were investigated for their antiproliferative activity. Among these compounds, several derivatives demonstrated significantly higher antiproliferative activity than ispinesib with nanomolar IC50 values against cell lines. Further evaluation indicated that the antiproliferative activity is not directly correlated with their KSP inhibitory activity while docking suggested that several of the derivatives may bind in a manner similar to ispinesib. In order to investigate the mode of action further, cell cycle analysis and reactive oxygen species formation were investigated. The improved antiproliferative activity of the most active compounds may be assigned to synergic effects of various factors such as KSP inhibitory activity due to the ispinesib core and ability to generate ROS and induce mitotic arrest.

Kinesin family member 11 promotes progression of hepatocellular carcinoma via the OCT4 pathway

Hepatocellular carcinoma (HCC) is the tumor with the second highest mortality rate worldwide. Recent research data show that KIF11, a member of the kinesin family (KIF), plays an important role in the progression of various tumors. However, its expression and molecular mechanism in HCC remain elusive. Here, we evaluated the potential role of KIF11 in HCC. The effect of KIF11 was evaluated using the hepatocellular carcinoma cell lines, LM3 and Huh7, after genetic or pharmacological treatment. Evaluating the role of KIF11 in the xenograft animal models using its specific inhibitor. The role of KIF11 was systematically evaluated using specimens obtained from the aforementioned animal and cell models after various in vivo and in vitro experiments. The clinicopathological analysis showed that KIF11 was expressed at high levels in patients with hepatocellular carcinoma. Cell experiments in vitro showed that KIF11 deficiency significantly slowed the proliferation of liver tumor cells. And in the experiment using liver cancer cells overexpressing OCT4, overexpression of OCT4 substantially increased the proliferation of tumor cells compared with tumor cells with KIF11 knockdown alone. Both in vitro cell experiment and in vivo xenotransplantation tumor experiment showed that monastrol, an inhibitor of KIF11, could effectively delay the proliferation and migration of tumor cells. Based on these results, KIF11 is expressed at high levels in hepatocellular carcinoma and promotes tumor proliferation in an OCT4-dependent manner. KIF11 may become a therapeutic target for hepatocellular carcinoma, and its inhibitor monastrol may become a clinical antitumor drug.

FOXM1a Isoform of Oncogene FOXM1 Is a Tumor Suppressor Suppressed by hnRNP C in Oral Squamous Cell Carcinoma

FOXM1 is an oncogenic transcriptional factor and includes several isoforms generated by alternative splicing. Inclusion of alternative exon 9 produces FOXM1a, a transcriptionally inactive isoform. However, the role of FOXM1a in tumorigenesis remains unknown. In addition, the regulatory mechanisms of exon 9 splicing are also unclear. In the present study, we found that overexpression of FOXM1a significantly reduced cell proliferation and colony formation of oral squamous cell carcinoma (OSCC) cell proliferation in vitro. Importantly, OSCC cells with FOXM1a overexpression showed significantly slower tumor formation in nude mice. Moreover, we identified a U-rich exonic splicing suppressor (ESS) which is responsible for exon 9 skipping. Splicing factor heterogeneous nuclear ribonucleoprotein C (hnRNP C) can bind to the ESS and suppress exon 9 inclusion and FOXM1a expression. Silence of hnRNP C also significantly suppresses OSCC cell proliferation. HnRNP C is significantly co-expressed with FOXM1 in cancers. Our study uncovered a novel regulatory mechanism of oncogene FOXM1 expression in OSCC.

Pan-cancer analysis of kinesin family members with potential implications in prognosis and immunological role in human cancer

Background

Kinesin is a molecular motor for transporting "goods" within cells and plays a key role in many types of tumors. The multi-angle study of kinesin at the pan-cancer level is conducive to understanding its role in tumorigenesis and development and clinical treatment potential.

Methods

We evaluated the expression of KIF genes, performed differential analysis by using the R package limma, and explored the pan-cancer prognosis of KIF genes by univariate Cox regression analysis. To evaluate the pan-cancer role of KIF genes as a whole, we defined the KIFscore with the help of gene set variation analysis (GSVA) and explored the KIFscores across normal tissues, tumor cell lines, and 33 tumor types in TCGA. Next, we used spearman correlation analysis to extensively study the correlation between the KIFscore and tumor prognosis and be-tween the KIFscore and clinical indicators. We also identified the relationship between the KIFscore and genomic variation and immune molecular signatures by multiplatform analysis. Finally, we identified the key genes in clear cell renal cell carcinoma (ccRCC) through machine learning algorithms and verified the candidate genes by CCK8, wound healing assay, Transwell assay, and flow cytometry.

Results

In most cancers, KIFscores are high and they act as a risk factor for cancer. The KIFscore was significantly associated with copy number variation (CNV), tumor mutation burden (TMB), immune subtypes, DNA repair deficiency, and tumor stemness indexes. Moreover, in almost all cancer species, the KIFscore was positively correlated with T cell CD4+ TH2, the common lymphoid pro-genitor, and the T cell follicular helper. In addition, it was negatively correlated with CXCL16, CCL14, TNFSF13, and TNFRSF14 and positively correlated with ULBP1, MICB, and CD276. Machine learning helped us to identify four hub-genes in ccRCC. The suitable gene, KIF14, is highly expressed in ccRCC and promotes tumor cell proliferation, migration, and invasion.

Conclusion

Our study shows that the KIF genes play an important pan-cancer role and may become a potential new target for a variety of tumor treatments in the future. Furthermore, KIF14, a key molecule in the KIF genes, can provide a new idea for the ccRCC treatment.

Organometallic Ru, Os, Rh and Ir half-sandwich conjugates of ispinesib - impact of the organometallic group on the antimitotic activity

Antimitotic agents are among the most important drugs used in anticancer therapy. Kinesin spindle protein (KSP) was proposed as a promising target for new antimitotic drugs. Herein, we report the synthesis of Ru, Os, Rh, and Ir half-sandwich complexes with the KSP inhibitor ispinesib and its (S)-enantiomer. Conjugation of the organometallic moiety with ispinesib and its (S)-enantiomer resulted in a significantly increased cytotoxicity of up to 5.6-fold compared to the parent compounds, with IC50 values in the nanomolar range. The most active derivatives were the ispinesib Ru and Rh conjugates which were able to generate reactive oxygen species (ROS), which may at least partially explain their high cytotoxicity. At the same time, the Os and Ir derivatives acted as KSP inhibitors with no effects on ROS generation.

A co-formulation of interferons alpha2b and gamma distinctively targets cell cycle in the glioblastoma-derived cell line U-87MG

BACKGROUND

HeberFERON is a co-formulation of α2b and γ interferons, based on their synergism, which has shown its clinical superiority over individual interferons in basal cell carcinomas. In glioblastoma (GBM), HeberFERON has displayed promising preclinical and clinical results. This led us to design a microarray experiment aimed at identifying the molecular mechanisms involved in the distinctive effect of HeberFERON compared to the individual interferons in U-87MG model.

METHODS

Transcriptional expression profiling including a control (untreated) and three groups receiving α2b-interferon, γ-interferon and HeberFERON was performed using an Illumina HT-12 microarray platform. Unsupervised methods for gene and sample grouping, identification of differentially expressed genes, functional enrichment and network analysis computational biology methods were applied to identify distinctive transcription patterns of HeberFERON. Validation of most representative genes was performed by qPCR. For the cell cycle analysis of cells treated with HeberFERON for 24 h, 48 and 72 h we used flow cytometry.

RESULTS

The three treatments show different behavior based on the gene expression profiles. The enrichment analysis identified several mitotic cell cycle related events, in particular from prometaphase to anaphase, which are exclusively targeted by HeberFERON. The FOXM1 transcription factor network that is involved in several cell cycle phases and is highly expressed in GBMs, is significantly down regulated. Flow cytometry experiments corroborated the action of HeberFERON on the cell cycle in a dose and time dependent manner with a clear cellular arrest as of 24 h post-treatment. Despite the fact that p53 was not down-regulated, several genes involved in its regulatory activity were functionally enriched. Network analysis also revealed a strong relationship of p53 with genes targeted by HeberFERON. We propose a mechanistic model to explain this distinctive action, based on the simultaneous activation of PKR and ATF3, p53 phosphorylation changes, as well as its reduced MDM2 mediated ubiquitination and export from the nucleus to the cytoplasm. PLK1, AURKB, BIRC5 and CCNB1 genes, all regulated by FOXM1, also play central roles in this model. These and other interactions could explain a G2/M arrest and the effect of HeberFERON on the proliferation of U-87MG.

CONCLUSIONS

We proposed molecular mechanisms underlying the distinctive behavior of HeberFERON compared to the treatments with the individual interferons in U-87MG model, where cell cycle related events were highly relevant.

Mitotic phosphorylation of Tau/MAPT modulates cell cycle progression in prostate cancer cells

PURPOSE

Tau/MAPT (microtubule associated protein tau) protein is actively studied for the pathologic consequences of its aberrant proteostasis in central nervous system leading to neurodegenerative diseases. Besides its ability to generate insoluble toxic oligomers, Tau homeostasis has attracted attention for its involvement in the formation of the mitotic spindle. This evidence, in association with the description of Tau expression in extra-neuronal tissues, and mainly in cancer tissues, constitutes the rationale for a more in-depth investigation of Tau role also in neoplastic diseases.

METHODS

In our study, we investigated the expression of phosphorylated Tau in prostate cancer cell lines with particular focus on the residue Thr231 present in microtubule binding domain.

RESULTS

The analysis of prostate cancer cells synchronized with nocodazole demonstrated that the expression of Tau protein phosphorylated at residue Thr231 is restricted to G2/M cell cycle phase. The phosphorylated form was unable to bind tubulin and it does not localize on mitotic spindle. As demonstrated by the use of specific inhibitors, the phosphorylation status of Tau is under the direct control of cdk5 and PP2A, while cdk1 activation was able to exert an indirect control. These mechanisms were also active in cells treated with docetaxel, where counteracting the expression of the dephosphorylated form, by kinase inhibition or protein silencing, determined resistance to drug toxicity.

CONCLUSIONS

We hypothesize that phosphorylation status of Tau is a key marker for G2/M phase in prostate cancer cells and that the forced modulation of Tau phosphorylation can interfere with the capacity of cell to efficiently progress through G2/M phase.

Overlaid Transcriptional and Proteome Analyses Identify Mitotic Kinesins as Important Targets of Arylsulfonamide-Mediated RBM39 Degradation

Certain arylsulfonamides (ArSulf) induce an interaction between the E3 ligase substrate adaptor DCAF15 and the critical splicing factor RBM39, ultimately causing its degradation. However, degradation of a splicing factor introduces complex pleiotropic effects that are difficult to untangle, since, aside from direct protein degradation, downstream transcriptional effects also influence the proteome. By overlaying transcriptional data and proteome datasets, we distinguish transcriptional from direct degradation effects, pinpointing those proteins most impacted by splicing changes. Using our workflow, we identify and validate the upregulation of the arginine-and-serine rich protein (RSRP1) and the downregulation of the key kinesin motor proteins KIF20A and KIF20B due to altered splicing in the absence of RBM39. We further show that kinesin downregulation is connected to the multinucleation phenotype observed upon RBM39 depletion by ArSulfs. Our approach should be helpful in the assessment of potential cancer drug candidates which target splicing factors.

IMPLICATIONS

Our approach provides a workflow for identifying and studying the most strongly modulated proteins when splicing is altered. The work also uncovers a splicing-based approach toward pharmacologic targeting of mitotic kinesins.

Exploring the therapeutic potential of the mitochondrial transfer-associated enzymatic machinery in brain degeneration

Mitochondrial dysfunction is a central event in the pathogenesis of several degenerative brain disorders. It entails fission and fusion dynamics disruption, progressive decline in mitochondrial clearance, and uncontrolled oxidative stress. Many therapeutic strategies have been formulated to reverse these alterations, including replacing damaged mitochondria with healthy ones. Spontaneous mitochondrial transfer is a naturally occurring process with different biological functions. It comprises mitochondrial donation from one cell to another, carried out through different pathways, such as the formation and stabilization of tunneling nanotubules and Gap junctions and the release of extracellular vesicles with mitochondrial cargoes. Even though many aspects of regulating these mechanisms still need to be discovered, some key enzymatic regulators have been identified. This review summarizes the current knowledge on mitochondrial dysfunction in different neurodegenerative disorders. Besides, we analyzed the usage of mitochondrial transfer as an endogenous revitalization tool, emphasizing the enzyme regulators that govern this mechanism. Going deeper into this matter would be helpful to take advantage of the therapeutic potential of mitochondrial transfer.

Noncoding RNAs-based high KIF26B expression correlates with poor prognosis and tumor immune infiltration in colon cancer

BACKGROUND

The protein kinesin family member 26B (KIF26B) is aberrantly expressed in various cancers. However, its particular role and association with tumor immune infiltration in colon adenocarcinoma (COAD) remain unclear.

METHODS

All original data were downloaded directly from The Cancer Genome Atlas (TCGA), UCSC Xena, and Gene Expression Omnibus (GEO) databases and processed with R 3.6.3. KIF26B expression was analyzed using Oncomine, TIMER, TCGA, GEO databases, and our clinical specimens. KIF26B expression at the protein level was explored with Human Protein Atlas (HPA) database. The upstream miRNAs and lncRNAs were predicted by StarBase and validated using RT-qPCR. Correlation of KIF26B expression with the expression of immune-related or immune checkpoint genes and GSEA analysis of KIF26B-related genes were investigated via R software. Relationship of KIF26B expression with immune biomarkers or tumor immune infiltration levels was studied through GEPIA2 and TIMER databases.

RESULTS

KIF26B was upregulated, and its overexpression was closely related to overall survival (OS), disease-specific survival (DSS), progression-free interval (PFI), T stage, N stage, and CEA levels in COAD. MIR4435-2HG/hsa-miR-500a-3p/KIF26B axis was identified as the promising regulatory pathway of KIF26B. KIF26B expression was positively correlated with immune-related genes, tumor immune infiltration, and biomarker genes of immune cells in COAD, and KIF26B-related genes were significantly enriched in macrophage activation-related pathways. Expression of immune checkpoint genes, including PDCD1, CD274, and CTLA4, was also closely related to KIF26B expression.

CONCLUSIONS

Our results clarified that ncRNA-based increased KIF26B expression was associated with a worse prognosis and high tumor immune infiltration in COAD.

Investigating the role of Kinesin family in lung adenocarcinoma via integrated bioinformatics approach

Lung cancer is the leading cause of mortality from cancer worldwide. Lung adenocarcinoma (LUAD) is a type of non-small cell lung cancer (NSCLC) with highest prevalence. Kinesins a class of motor proteins are shown to be involved in carcinogenesis. We conducted expression, stage plot and survival analyses on kinesin superfamily (KIF) and scrutinized the key prognostic kinesins. Genomic alterations of these kinesins were studied thereafter via cBioPortal. A protein-protein interaction network (PPIN) of selected kinesins and 50 closest altering genes was constructed followed by gene ontology (GO) term and pathway enrichment analyses. Multivariate survival analysis based on CpG methylation of selected kinesins was performed. Lastly, we conducted tumor immune infiltration analysis. Our results found KIF11/15/18B/20A/2C/4A/C1 to be significantly upregulated and correlated with poor survival in LUAD patients. These genes also showed to be highly associated with cell cycle. Out of our seven selected kinesins, KIFC1 showed the highest genomic alteration with highest number of CpG methylation. Also, CpG island (CGI) cg24827036 was discovered to be linked to LUAD prognosis. Therefore, we deduced that reducing the expression of KIFC1 could be a feasible treatment strategy and that it can be a wonderful individual prognostic biomarker. CGI cg24827036 can also be used as a therapy site in addition to being a great prognostic biomarker.

Network and functional analyses of differentially expressed genes in gastric cancer provide new biomarkers associated with disease pathogenesis

BACKGROUND

Gastric cancer is a dominant source of cancer-related death around the globe and a serious threat to human health. However, there are very few practical diagnostic approaches and biomarkers for the treatment of this complex disease.

METHODS

This study aimed to evaluate the association between differentially expressed genes (DEGs), which may function as potential biomarkers, and the diagnosis and treatment of gastric cancer (GC). We constructed a protein-protein interaction network from DEGs followed by network clustering. Members of the two most extensive modules went under the enrichment analysis. We introduced a number of hub genes and gene families playing essential roles in oncogenic pathways and the pathogenesis of gastric cancer. Enriched terms for Biological Process were obtained from the "GO" repository.

RESULTS

A total of 307 DEGs were identified between GC and their corresponding normal adjacent tissue samples in GSE63089 datasets, including 261 upregulated and 261 downregulated genes. The top five hub genes in the PPI network were CDK1, CCNB1, CCNA2, CDC20, and PBK. They are involved in focal adhesion formation, extracellular matrix remodeling, cell migration, survival signals, and cell proliferation. No significant survival result was found for these hub genes.

CONCLUSIONS

Using comprehensive analysis and bioinformatics methods, important key pathways and pivotal genes related to GC progression were identified, potentially informing further studies and new therapeutic targets for GC treatment.

E3 ubiquitin ligase ASB8 promotes selinexor-induced proteasomal degradation of XPO1

Selinexor (KPT-330), a small-molecule inhibitor of exportin-1 (XPO1, CRM1) with potent anticancer activity, has recently been granted FDA approval for treatment of relapsed/refractory multiple myeloma and diffuse large B-cell lymphoma (DLBCL), with a number of additional indications currently under clinical investigation. Since selinexor has often demonstrated synergy when used in combination with other drugs, notably bortezomib and dexamethasone, a more comprehensive approach to uncover new beneficial interactions would be of great value. Moreover, stratifying patients, personalizing therapeutics and improving clinical outcomes requires a better understanding of the genetic vulnerabilities and resistance mechanisms underlying drug response. Here, we used CRISPR-Cas9 loss-of-function chemogenetic screening to identify drug-gene interactions with selinexor in chronic myeloid leukemia, multiple myeloma and DLBCL cell lines. We identified the TGFβ-SMAD4 pathway as an important mediator of resistance to selinexor in multiple myeloma cells. Moreover, higher activity of this pathway correlated with prolonged progression-free survival in multiple myeloma patients treated with selinexor, indicating that the TGFβ-SMAD4 pathway is a potential biomarker predictive of therapeutic outcome. In addition, we identified ASB8 (ankyrin repeat and SOCS box containing 8) as a shared modulator of selinexor sensitivity across all tested cancer types, with both ASB8 knockout and overexpression resulting in selinexor hypersensitivity. Mechanistically, we showed that ASB8 promotes selinexor-induced proteasomal degradation of XPO1. This study provides insight into the genetic factors that influence response to selinexor treatment and could support both the development of predictive biomarkers as well as new drug combinations.

KIFC3 regulates progression of hepatocellular carcinoma via EMT and the AKT/mTOR pathway

INTRODUCTION

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related deaths worldwide. Despite an overall downward trend in cancer mortality, HCC-related mortality continues to increase. KIFC3 is involved in cell division and cancers. However, the role of KIFC3 in HCC has yet to be elucidated.

METHODS

A total of 36 cases of HCC tissues, 4 HCC cell lines, and TCGA databases were searched to explore the expression of KIFC3 in HCC. Subsequently, Western blot analysis, immunofluorescence, bioinformatic analysis, molecular docking, and Co-IP were performed to investigate the molecular mechanisms of KIFC3 in HCC.

RESULT

We found that the expression of KIFC3 was upregulated in HCC, and high KIFC3 expression was related to poor overall survival. In addition, the knockdown of KIFC3 inhibited the proliferation, migration, and invasion of HCC cells in vitro, and impeded the growth of HCC in vivo, while overexpression of KIFC3 in HCC cells revealed the opposite effect. Mechanistically, KIFC3 promotes the progression of HCC through the PI3K/AKT/mTOR signalling. And KIFC3 had slight effect on the protein expression of p-PI3K, p-AKT and p-mTOR in TRIP13-ablated or LY294002-treated HCC cells. The KIFC3 knockdown could further enhance the inhibitory effect of LY294002.

CONCLUSION

Our data revealed that KIFC3 is upregulated in HCC and may serve as a novel biomarker for predicting survival in HCC patients. Targeting KIFC3 may serve as a novel therapeutic strategy for HCC patients.

A pan-cancer landscape of centromere proteins in tumorigenesis and anticancer drug sensitivity

BACKGROUND

During mitosis and meiosis, centromere proteins (CENPs) play a key role in proper chromosome segregation. Abnormal expression of CENPs leads to chromosome instability, which is the main cause of tumorigenesis.

METHODS

To elucidate the functional characteristics of CENPs in pan-cancer, we comprehensively analyzed the expression landscape of CENPs and their relationships with patient survival, genomic alterations, tumor immunity, tumor microenvironment, and anticancer drug sensitivity. The expression patterns and signaling pathways of CENPs were identified through multiple bioinformatics mining and experimental verification. GEPIA2 and PrognoScan were implemented to evaluate the prognostic value of CENPs. The molecular functions of CENPs in pan-cancer were comprehensively assessed using cBioPortal, GSCA, ImmuCellAI, CellMiner, the ROC plotter tool and TIDE.

RESULTS

The results showed that CENPs were upregulated in most tumors compared with normal tissues. We confirmed this conclusion by immunohistochemistry and real-time quantitative PCR. Survival analysis revealed a significant association between high CENP expression and a poor prognosis. CENP expression is related to genome alterations, copy number variation, single nucleotide variation and methylation. Among CENP family genes, CENPF and CENPE are mutated at high frequencies in various tumors, while CENPM and CENPA are less frequently mutated. Furthermore, CENPs regulate the tumor mutational burden, stemness, and microsatellite instability, and are associated with tumor immunity. Most importantly, we revealed that CENP family gene expression was correlated with chemosensitivity and immunotherapy responses.

CONCLUSION

These findings may clarify the role of CENPs in cancer progression and antitumor drug sensitivity and provide evidence for CENPs as a potential target in pan-cancer.

KIF14 mediates cabazitaxel-docetaxel cross-resistance in advanced prostate cancer by promoting AKT phosphorylation

Docetaxel is a first-line chemotherapy drug for castration-resistant prostate cancer (CRPC); yet, some CRPC patients develop docetaxel drug resistance. Cabazitaxel is approved in the post-docetaxel treatment setting. However, recent studies suggested cross-resistance between the development of drug resistance and current treatments. In this study, we used docetaxel-resistant cell lines DU145/DTX50 and PC-3/DTX30 to measure the responses to cabazitaxel. Our findings demonstrated that docetaxel resistance could lead to cross-resistance to cabazitaxel. After docetaxel-resistant cells were treated with cabazitaxel, transcriptome analysis was performed, and the results were analyzed in combination with survival analysis and correlation analysis with Gleason score to screen the cross-resistance genes. The continuously increased expression of kinesin family member 14 (KIF14) was identified as the main cause of cross-resistance to cabazitaxel in docetaxel-resistant cells. Silencing the expression of KIF14 could restore the sensitivity of resistant PCa cells to docetaxel and cabazitaxel, attenuate proliferation and promote apoptosis of the resistant PCa cells. Notably, the depressed expression of KIF14 inhibited the phosphorylation of Akt located downstream. In summary, KIF14 mediates the cross-resistance between docetaxel and cabazitaxel, and targeting KIF14 could be an effective measurement for reversing docetaxel or cabazitaxel chemotherapy failure or enhancing the anti-tumor effects of docetaxel or cabazitaxel.

Inter and intracellular mitochondrial transfer: Future of mitochondrial transplant therapy in Parkinson's disease

Parkinson's disease (PD) is marked by the gradual degeneration of dopaminergic neurons and the intracellular build-up of Lewy bodies rich in α-synuclein protein. This impairs various aspects of the mitochondria including the generation of ROS, biogenesis, dynamics, mitophagy etc. Mitochondrial dynamics are regulated through the inter and intracellular movement which impairs mitochondrial trafficking within and between cells. This inter and intracellular mitochondrial movement plays a significant role in maintaining neuronal dynamics in terms of energy and growth. Kinesin, dynein, myosin, Mitochondrial rho GTPase (Miro), and TRAK facilitate the retrograde and anterograde movement of mitochondria. Enzymes such as Kinases along with Calcium (Ca²⁺), Adenosine triphosphate (ATP) and the genes PINK1 and Parkin are also involved. Extracellular vesicles, gap junctions, and tunneling nanotubes control intercellular movement. The knowledge and understanding of these proteins, enzymes, molecules, and movements have led to the development of mitochondrial transplant as a therapeutic approach for various disorders involving mitochondrial dysfunction such as stroke, ischemia and PD. A better understanding of these pathways plays a crucial role in establishing extracellular mitochondrial transplant therapy for reverting the pathology of PD. Currently, techniques such as mitochondrial coculture, mitopunch and mitoception are being utilized in the pre-clinical stages and should be further explored for translational value. This review highlights how intercellular and intracellular mitochondrial dynamics are affected during mitochondrial dysfunction in PD. The field of mitochondrial transplant therapy in PD is underlined in particular due to recent developments and the potential that it holds in the near future.

Application of magnetic solid-phase extraction for sensitive determination of anticancer drugs in urine by means of diamino benzidine tetrachlorohydrate modified magnetic nanoparticles

BACKGROUND

The analysis of drug active molecules and residues in the treatment of cancer is important for the sustainability of human life and therapeutic effects. For this purpose, a new magnetic sorbent was developed to use in solid phase extraction prior to conventional high-performance liquid chromatography (HPLC) analysis of Paclitaxel (PAC) and Gemcitabine (GEM) molecules.

METHODS

In this study, a separation and pre-concentration approach based on magnetic solid phase extraction (MSPE) was proposed for PAC and GEM by means of using a newly synthesized magnetic sorbent. After the MSPE procedure, an HPLC system with a diode array detector (DAD) was used to analyze trace amounts of PAC and GEM anticarcinogenic drugs in urine samples. Surface modification of magnetic Fe₃O₄ nanoparticles was carried out by diaminobenzidinetetrachloro hydrate (DABTC) for the first time and a useful sorbent was obtained for MSPE experiments.

RESULTS

In the proposed method, PAC and GEM molecules were retained on the c in the presence of a pH 5.0 medium and desorbed to 300 μL of acetonitrile: methyl alcohol (1:1) eluent phase before HPLC-DAD analysis. Under the optimized conditions, the limit of detection (LOD) values for PAC and GEM were 1.38 and 1.44 ng mL^-1 while the enhancement factor for PAC and GEM were 139.5 and 145.3, respectively. The relative standard deviations (RSD %) for PAC and GEM were below 3.50% in inter-day repeated experiments by means of model solutions containing 100 ng mL^-1 drug active ingredients.

CONCLUSIONS

Synthesis and characterization of DABTC-Fe₃O₄ nanoparticles were performed using suitable methodologies. Optimization of MSPE was done step by step. And finally, the developed method was successfully applied to urine samples with quantitative recoveries in the range of 99.0% and 105.0%.

Identification of the KIF and MCM protein families as novel targets for combination therapy with CDK4/6 inhibitors in bladder cancer

CDK4/6 inhibitors have proven their potency for the treatment of cancer but only in combination with hormone or targeted therapies. The aim of this study was the identification of molecules that are involved in response mechanisms to CDK4/6 inhibitors and the development of novel combination therapies with corresponding inhibitors in bladder cancer. Genes of response to therapy and genes that confer resistance to the CDK4/6 inhibitor palbociclib were identified by performing an analysis of published literature and own published data using a CRISPR-dCas9 genome wide gain of function screen. Genes that were down-regulated upon treatment were compared with genes that confer resistance when up-regulated. Two of the top 5 genes were validated by quantitative PCR and western blotting upon treatment with palbociclib in the bladder cancer cell lines T24, RT112 and UMUC3. As inhibitors for combination therapy, we used ciprofloxacin, paprotrain, ispinesib and SR31527. Analysis of synergy was done using the "zero interaction potency" model. Cell growth was examined using sulforhodamine B staining. A list of genes that met the requirements for inclusion in the study was generated from 7 publications. Of the 5 most relevant genes, MCM6 and KIFC1 were chosen and their down-regulation upon treatment with palbociclib was confirmed by qPCR and immunoblotting. The combination of inhibitors against both, KIFC1 and MCM6 with PD resulted in a synergistic inhibition of cell growth. We have identified 2 molecular targets whose inhibition has promising potential for effective combination therapies with the CDK4/6 inhibitor palbociclib.

ERCC6L facilitates the progression of laryngeal squamous cell carcinoma by the binding of FOXM1 and KIF4A

The role of excision repair cross-complementation group 6-like (ERCC6L) has been reported in several cancers, but little is known about its expression and function in laryngeal squamous cell carcinoma (LSCC). In this study, the expression of ERCC6L in LSCC was determined by immunohistochemistry and its correlation with prognostic factors was analyzed. Furthermore, cytological functional validation elucidated the role and underlying mechanisms of ERCC6L dysregulation in LSCC. Our data revealed that ERCC6L expression was elevated in LSCC and it's correlated with TNM stage. In addition, ERCC6L knockdown LSCC cells showed decreased proliferation and migration, increased apoptosis, and reactive oxygen species (ROS). Mechanically, overexpression of ERCC6L promoted nuclear translocation of FOXM1 to facilitate direct binding to the KIF4A promoter and upregulated KIF4A expression. Furthermore, KIF4A knockdown attenuated the role of ERCC6L overexpression in promoting proliferation, migration, and tumorigenesis of LSCC cells. In summary, ERCC6L promoted the binding of FOXM1 and KIF4A in LSCC cells to drive their progression, which may be a promising target for precision therapy in this disease.

Nanoparticle-Based Combination Therapy for Ovarian Cancer

Ovarian cancer is one of the most common malignant tumors in gynecology with a high incidence. Combination therapy, eg, administration of paclitaxel followed by a platinum anticancer drug is recommended to treat ovarian cancer due to its advantages in, eg, reducing side effects and reversing (multi)drug-resistance compared to single treatment. However, the benefits of combination therapy are often compromised. In chemo and chemo/gene combinations, co-deposition of the combined therapeutics in the tumor cells is required, which is difficult to achieve due to dramatic pharmacokinetic differences between combinational agents in free forms. Moreover, some undesired properties such as the low-water solubility of chemodrugs and the difficulty of cellular internalization of gene therapeutics also hinder the therapeutic potential. Delivery of dual or multiple agents by nanoparticles provides opportunities to tackle these limits. Nanoparticles encapsulate hydrophobic drug(s) to yield aqueous dispersions facilitating its administration and/or to accommodate hydrophilic genes facilitating its access to cells. Moreover, nanoparticle-based therapeutics can not only improve drug properties (eg, in vivo stability) and ensure the same drug disposition behavior with controlled drug ratios but also can minimize drug exposure of the normal tissues and increase drug co-accumulation at targeted tissues via passive and/or active targeting strategies. Herein, this work summarizes nanoparticle-based combination therapies, mainly including anticancer drug-based combinations and chemo/gene combinations, and emphasizes the advantageous outcomes of nanocarriers in the combination treatment of ovarian cancer. In addition, we also review mechanisms of synergetic effects resulting from different combinations.

Combined Inhibition of KIF11 and KIF15 as an Effective Therapeutic Strategy for Gastric Cancer

BACKGROUND

Novel therapeutic strategies are urgently required to improve clinical outcomes of gastric cancer (GC). KIF15 cooperates with KIF11 to promote bipolar spindle assembly and formation, which is essential for proper sister chromatid segregation. Therefore, we speculated that the combined inhibition of KIF11 and KIF15 might be an effective strategy for GC treatment. Hence, to test this hypothesis, we aimed to evaluate the combined therapeutic effect of KIF15 inhibitor KIF15- IN-1 and KIF11 inhibitor ispinesib in GC.

METHODS

We validated the expression of KIF11 and KIF15 in GC tissues using immunohistochemistry and immunoblotting. Next, we determined the effects of KIF11 or KIF15 knockout on the proliferation of GC cell lines. Finally, we investigated the combined effects of the KIF11 and KIF15 inhibitors both in vitro and in vivo.

RESULTS

KIF11 and KIF15 were overexpressed in GC tissues than in the adjacent normal tissues. Knockout of either KIF11 or KIF15 inhibited the proliferative and clonogenic abilities of GC cells. We found that the KIF15 knockout significantly increased ispinesib sensitivity in GC cells, while its overexpression showed the opposite effect. Further, using KIF15-IN-1 and ispinesib together had a synergistic effect on the antitumor proliferation of GC both in vitro and in vivo.

CONCLUSION

This study shows that the combination therapy of inhibiting KIF11 and KIF15 might be an effective therapeutic strategy against gastric cancer.

Design of MMP-1 inhibitors via SAR transfer and experimental validation

New matrix metalloproteinase 1 (MMP-1) inhibitors were predicted using the structure-activity relationship (SAR) transfer method based on a series of analogues of kinesin-like protein 11 (KIF11) inhibitors. Compounds 5-7 predicted to be highly potent against MMP-1 were synthesized and tested for MMP-1 inhibitory activity. Among these, compound 6 having a Cl substituent at the R¹ site was found to possess ca. 3.5 times higher inhibitory activity against MMP-1 than the previously reported compound 4. The observed potency was consistent with the presence of an SAR transfer event between analogous MMP-1 and KIF11 inhibitors. Pharmacophore fitting revealed that the higher inhibitory activity of compound 6 compared to compound 4 against MMP-1 might be due to a halogen bond interaction between the Cl substituent of compound 6 and residue ARG214 of MMP-1.

Identification of KIF21B as a Biomarker for Colorectal Cancer and Associated with Poor Prognosis

OBJECTIVE

This study is aimed at exploring the function of KIF21B in colorectal cancer.

METHODS

The expression of KIF21B was analyzed by the UALCAN database, GEPIA site, and TIMER site. The survival rate was analyzed by Kaplan-Meier curves, and the prognosis was analyzed by ROC. Relevant signaling pathways and biological processes were analyzed by GO-KEGG enrichment analysis. The correlation between KIF21B and cancer immune infiltrates was analyzed by TIMER. The functional state of KIF21B in various types of cancers was conducted by single-cell RNA-sequencing. Furthermore, the expression of KIF21B was verified by real-time qPCR and Western blotting. The cell proliferation was measured by CCK8 assay. The cell apoptosis was analyzed by flow cytometry. Cell migration and invasion were determined by the transwell assay.

RESULTS

Combination analysis of bioinformatics methods revealed that KIF21B is high expression in CRC, associated with poor survival. KIF21B and associated genes were significantly enriched in covalent chromatin modification. The expression of KIF21B was positively correlated with infiltrating levels of CD4+ T cells and neutrophils, cell apoptosis, and metastasis. KIF21B was upregulated expression in CRC cell lines. KIF21B deficiency reduced cell proliferation, migration, and invasion.

CONCLUSIONS

Our study suggested that KIF21B may be a biomarker in CRC.

Magic-angle-spinning NMR structure of the kinesin-1 motor domain assembled with microtubules reveals the elusive neck linker orientation

Microtubules (MTs) and their associated proteins play essential roles in maintaining cell structure, organelle transport, cell motility, and cell division. Two motors, kinesin and cytoplasmic dynein link the MT network to transported cargos using ATP for force generation. Here, we report an all-atom NMR structure of nucleotide-free kinesin-1 motor domain (apo-KIF5B) in complex with paclitaxel-stabilized microtubules using magic-angle-spinning (MAS) NMR spectroscopy. The structure reveals the position and orientation of the functionally important neck linker and how ADP induces structural and dynamic changes that ensue in the neck linker. These results demonstrate that the neck linker is in the undocked conformation and oriented in the direction opposite to the KIF5B movement. Chemical shift perturbations and intensity changes indicate that a significant portion of ADP-KIF5B is in the neck linker docked state. This study also highlights the unique capability of MAS NMR to provide atomic-level information on dynamic regions of biological assemblies.