Eg5 Overexpression Is Predictive of Poor Prognosis in Hepatocellular Carcinoma Patients

Mitotic Functions and Characters of KIF11 in Cancers

Mitosis mediates the accurate separation of daughter cells, and abnormalities are closely related to cancer progression. KIF11, a member of the kinesin family, plays a vital role in the formation and maintenance of the mitotic spindle. Recently, an increasing quantity of data have demonstrated the upregulated expression of KIF11 in various cancers, promoting the emergence and progression of cancers. This suggests the great potential of KIF11 as a prognostic biomarker and therapeutic target. However, the molecular mechanisms of KIF11 in cancers have not been systematically summarized. Therefore, we first discuss the functions of the protein encoded by KIF11 during mitosis and connect the abnormal expression of KIF11 with its clinical significance. Then, we elucidate the mechanism of KIF11 to promote various hallmarks of cancers. Finally, we provide an overview of KIF11 inhibitors and outline areas for future work.

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).

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.

KIF11 Is a Promising Therapeutic Target for Thyroid Cancer Treatment

Objective. To assess KIF11 expression in human thyroid tumor tissues and further evaluate its involvement in thyroid cancer. Methods. The expression of KIF11 in 71 cases of thyroid carcinoma as well as corresponding tissues was detected by the immunohistochemical (IHC) method. Patients were divided into the high KIF11 expression as well as low expression groups based on the staining levels. In addition, to study the relationship between the expression of KIF11 as well as clinicopathological features, the effects of KIF11 were detected on the proliferation, apoptosis, and cell cycle of two types of thyroid cancer cells, TPC-1 and KTC-1, through colony formation assays, MTT assays, and FCM assays, respectively. We further assessed the potential effects of KIF11 on tumor growth using an animal model. Results. The significantly high expression of KIF11 in thyroid tumor tissues was revealed, and the correlations between KIF11 expression levels as well as clinical pathological features (T stage and intraglandular dissemination) of patients were revealed. We further noticed that KIF11 knockdown remarkably suppressed thyroid cancer cell proliferation as well as induced cell apoptosis of thyroid cancer cells. Additionally, KIF11 contributed to tumor growth of thyroid cancer cells in mice. Conclusions. We noticed the involvement of KIF11 in the progression of thyroid cancer.

Development and physiological functions of the lymphatic system: insights from human genetic studies of primary lymphedema

Primary lymphedema is a long-term (chronic) condition characterized by tissue lymph retention and swelling that can affect any part of the body, although it usually develops in the arms or legs. Due to the relevant contribution of the lymphatic system to human physiology, while this review mainly focuses on the clinical and physiological aspects related to the regulation of fluid homeostasis and edema, clinicians need to know that the impact of lymphatic dysfunction with a genetic origin can be wide ranging. Lymphatic dysfunction can affect immune function so leading to infection; it can influence cancer development and spread, and it can determine fat transport so impacting on nutrition and obesity. Genetic studies and the development of imaging techniques for the assessment of lymphatic function have enabled the recognition of primary lymphedema as a heterogenic condition in terms of genetic causes and disease mechanisms. In this review, the known biological functions of several genes crucial to the development and function of the lymphatic system are used as a basis for understanding normal lymphatic biology. The disease conditions originating from mutations in these genes are discussed together with a detailed clinical description of the phenotype and the up-to-date knowledge in terms of disease mechanisms acquired from in vitro and in vivo research models.

Exploratory comparisons between different anti-mitotics in clinically-used drug combination in triple negative breast cancer

Triple-negative breast cancer (TNBC) constitutes a very aggressive type of breast cancer with few options of cytotoxic chemotherapy available for them. A chemotherapy regimen comprising of doxorubicin hydrochloride and cyclophosphamide, followed by paclitaxel, known as AC-T, is approved for usage as an adjuvant treatment for this type of breast cancer. In this study we aimed to elucidate the role of KIF11 in TNBC progression throughout its inhibition by two synthetic small molecules containing the DHPM core (dihydropyrimidin-2(1H)-ones or -thiones), with the hypothesis that these inhibitors could be an interesting option of antimitotic drug used alone or as adjuvant therapy in association with AC. For this purpose, we evaluated the efficacy of DHPMs used as monotherapy or in combination with doxorubicin and cyclophosphamide, in Balbc-nude mice bearing breast cancer induced by MDA-MB-231, having AC-T as positive control. Our data provide extensive evidence to demonstrate that KIF11 inhibitors showed pronounced antitumor activity, acting in key points of tumorigenesis and cancer progression in in vivo xenograft model of triple negative breast cancer, like down-regulation of KIF11 and ALDH1-A1. Moreover, they didn’t show the classic peripheral neuropathy characterized by impaired mobility, as it is common with paclitaxel use. These results suggest that the use of a MAP inhibitor in breast cancer regimen treatment could be a promising strategy to keep antitumoral activity reducing the side effects.

Inhibitor library screening identifies ispinesib as a new potential chemotherapeutic agent for pancreatic cancers

Screening custom‐made libraries of inhibitors may reveal novel drugs for treating pancreatic cancer. In this manner, we identified ispinesib as a candidate and attempted to determine its clinical efficacy and the biological significance of its functional target Eg5 in pancreatic cancer. One hundred compounds in our library were screened for candidate drugs using cell cytotoxicity assays. Ispinesib was found to mediate effective antitumor effects in pancreatic cancer. The clinical significance of the expression of the ispinesib target Eg5 was investigated in 165 pancreatic cancer patients by immunohistochemical staining and in Eg5‐positive pancreatic cancer patient‐derived xenograft (PDX) mouse models. Patients with Eg5‐positive tumors experienced significantly poorer clinical outcomes than those not expressing Eg5 (overall survival; P < .01, recurrence‐free survival; P < .01). Ispinesib or Eg5 inhibition with specific siRNA significantly suppressed cell proliferation and induced apoptosis in pancreatic cancer cell lines. Mechanistically, ispinesib acted by inducing incomplete mitosis with nuclear disruption, resulting in multinucleated monoastral spindle cells. In the PDX mouse model, ispinesib dramatically reduced tumor growth relative to vehicle control (652.2 mm³ vs 18.1 mm³ in mean tumor volume, P < .01 by ANOVA; 545 mg vs 28 mg in tumor weight, P < .01, by ANOVA). Ispinesib, identified by inhibitor library screening, could be a promising novel therapeutic agent for pancreatic cancer. The expression of its target Eg5 is associated with poorer postoperative prognosis and is important for the clinical efficacy of ispinesib in pancreatic cancer.

ASPM combined with KIF11 promotes the malignant progression of hepatocellular carcinoma via the Wnt/β-catenin signaling pathway

To investigate the molecular mechanism of assembly factor for spindle microtubules (ASPM) in the regulation of the malignant progression of hepatocellular carcinoma (HCC), bioinformatics analysis was utilized to analyze the role of ASPM in the malignant progression of HCC and its potential interaction with the kinesin family member 11 (KIF11) gene. The expression levels of ASPM and KIF11 were detected by reverse transcription-quantitative PCR and western blotting. Following knockdown of ASPM expression, Cell Counting Kit-8/colony formation assays were performed to detect cell viability and proliferation. Wound healing and Transwell assays were employed to detect cell migration and invasion. Additionally, a co-immunoprecipitation (CO-IP) assay was used to detect whether there was an interaction between ASPM and KIF11. KIF11 overexpression was performed to verify if ASPM exerted its effects via KIF11. ASPM was highly expressed in HCC tissues and cells, and was closely associated with a poor prognosis of patients with HCC. Interference with ASPM expression markedly inhibited the viability, proliferation, invasion and migration of HCC cells. Using a CO-IP assay, it was revealed that there was an interaction between ASPM and KIF11. Rescue experiments subsequently revealed the regulatory effects of ASPM on the activity, proliferation, invasion and migration of HCC cells via KIF11. Finally, western blot analysis demonstrated that ASPM in combination with KIF11 promoted the malignant progression of HCC by regulating the activity of the Wnt/β-catenin signaling pathway. Therefore, the present study demonstrated that ASPM may interact with KIF11 in HCC cells to promote the malignant progression of HCC via the Wnt/β-catenin signaling pathway.

Prognostic Impact and Functional Annotations of KIF11 and KIF14 Expression in Patients with Colorectal Cancer

Genomic instability (GIN) has an important contribution to the pathology of colorectal cancer (CRC). Therefore, we selected mitosis and cytokinesis kinesins, KIF11 and KIF14, as factors of potential clinical and functional value in CRC, as their aberrant expression has been suspected to underlie GIN. We examined the expression and the prognostic and biological significance of KIF11 and KIF14 in CRC via in-house immunohistochemistry on tissue microarrays, public mRNA expression datasets, as well as bioinformatics tools. We found that KIF11 and KIF14 expression, at both the protein and mRNA level, was markedly altered in cancer tissues compared to respective controls, which was reflected in the clinical outcome of CRC patients. Specifically, we provide the first evidence that KIF11 protein and mRNA, KIF14 mRNA, as well as both proteins together, can significantly discriminate between CRC patients with better and worse overall survival independently of other relevant clinical risk factors. The negative prognostic factors for OS were high KIF11 protein, high KIF11 protein + low KIF14 protein, low KIF11 mRNA and low KIF14 mRNA. Functional enrichment analysis revealed that the gene sets related to the cell cycle, DNA replication, DNA repair and recombination, among others, were positively associated with KIF11 or KIF14 expression in CRC tissues. In TCGA cohort, the positive correlations between several measures related to GIN and the expression of KIFs were also demonstrated. In conclusion, our results suggest that CRC patients can be stratified into distinct risk categories by biological and molecular determinants, such as KIF11 and KIF14 expression and, mechanistically, this is likely attributable to their role in maintaining genome integrity.

Eg5 as a Prognostic Biomarker and Potential Therapeutic Target for Hepatocellular Carcinoma

BACKGROUND

The kinesin Eg5, a mitosis-associated protein, is overexpressed in many cancers. Here we explored the clinical significance of Eg5 in hepatocellular carcinoma (HCC).

METHODS

HCC tissues from surgical resection were collected. Total RNA was prepared from tumorous and nontumorous parts. Eg5 expression levels were correlated with overall survival (OS) and disease-free survival (DFS). In vitro efficacy of LGI-147, a specific Eg5 inhibitor, was tested in HCC cell lines. In vivo efficacy of Eg5 inhibition was investigated in a xenograft model.

RESULTS

A total of 108 HCC samples were included. The patients were divided into three tertile groups with high, medium, and low Eg5 expression levels. OS of patients with low Eg5 expression was better than that of patients with medium and high Eg5 expression (median, 155.6 vs. 75.3 vs. 57.7 months, p = 0.002). DFS of patients with low Eg5 expression was also better than that of patients with medium and high Eg5 expression (median, 126.3 vs. 46.2 vs. 39.4 months, p = 0.001). In multivariate analyses, the associations between Eg5 expression and OS (p < 0.001) or DFS remained (p < 0.001). LGI-147 reduced cell growth via cell cycle arrest and apoptosis and induced accumulation of abnormal mitotic cells. In the xenograft model, the tumor growth rate under LGI-147 treatment was significantly slower than under the control.

CONCLUSION

High Eg5 expression was associated with poor HCC prognosis. In vitro and in vivo evidence suggests that Eg5 may be a reasonable therapeutic target for HCC.

Second-Generation Antimitotics in Cancer Clinical Trials

Mitosis represents a promising target to block cancer cell proliferation. Classical antimitotics, mainly microtubule-targeting agents (MTAs), such as taxanes and vinca alkaloids, are amongst the most successful anticancer drugs. By disrupting microtubules, they activate the spindle assembly checkpoint (SAC), which induces a prolonged delay in mitosis, expected to induce cell death. However, resistance, toxicity, and slippage limit the MTA's effectiveness. With the desire to overcome some of the MTA's limitations, mitotic and SAC components have attracted great interest as promising microtubule-independent targets, leading to the so-called second-generation antimitotics (SGAs). The identification of inhibitors against most of these targets, and the promising outcomes achieved in preclinical assays, has sparked the interest of academia and industry. Many of these inhibitors have entered clinical trials; however, they exhibited limited efficacy as monotherapy, and failed to go beyond phase II trials. Combination therapies are emerging as promising strategies to give a second chance to these SGAs. Here, an updated view of the SGAs that reached clinical trials is here provided, together with future research directions, focusing on inhibitors that target the SAC components.

Prognostic Significance of KIF11 and KIF14 Expression in Pancreatic Adenocarcinoma

Simple Summary

Prognostic markers for survival stratification of patients with pancreatic adenocarcinoma (PAC) are missing yet. Therefore, the primary aim of this study was to assess the expression, clinical associations, and survival implications of KIF11 and KIF14 in PACs. In addition, the genes co-expressed with KIF11 or KIF14 were predicted and functionally annotated. Herein, we found that the expression patterns of KIF11 and KIF14 alter significantly in PACs, at both protein and mRNA levels, and this may be harnessed for patient prognosis. KIF11 and KIF14 could be defined as positive prognostic biomarkers based on the protein-based immunohistochemistry data, while they were associated with adverse prognosis based on the transcriptomic data. We also captured a five-gene prognostic signature and the biology associated with it. The findings of the present study suggest that KIF11 or KIF14 proteins, as well as a new five-gene panel, may serve as potentially useful prognostic biomarkers for PAC.

Abstract

Available biomarkers for pancreatic adenocarcinoma (PAC) are inadequate to guide individual patient prognosis or therapy. Therefore, herein we aimed to verify the hypothesis that differences in the expression of KIF11 and KIF14, i.e., molecular motor proteins being primarily implicated in cell division events could account for the differences in the clinical outcome of PAC patients. In-house immunohistochemistry was used to evaluate the protein expressions of KIF11 and KIF14 in PAC, whereas RNA-seq datasets providing transcript expression data were obtained from public sources. IHC and mRNA results were correlated with clinicopathological features and overall survival (OS). Furthermore, the genes co-expressed with KIF11 or KIF14 were predicted and functionally annotated. In our series, malignant ducts displayed more intense but less abundant KIF11 staining than normal-appearing ducts. The former was also true for KIF14, whereas the prevalence of positive staining was similar in tumor and normal adjacent tissues. Based on categorical immunoreactive scores, we found KIF11 and KIF14 to be frequently downregulated or upregulated in PAC cases, respectively, and those with elevated levels of either protein, or both together, were associated with better prognosis. Specifically, we provide the first evidence that KIF11 or KIF14 proteins can robustly discriminate between patients with better and worse OS, independently of other relevant clinical risk factors. In turn, mRNA levels of KIF11 and KIF14 were markedly elevated in tumor tissues compared to normal tissues, and this coincided with adverse prognosis, even after adjusting for multiple confounders. Tumors with low predicted KIF11 or KIF14 expression were seen to have enrichment for circadian clock, whereas those with high levels were enriched for the genomic instability-related gene set. KIF11 and KIF14 were strongly correlated with one another, and CEP55, ASPM, and GAMT were identified as the main hub genes. Importantly, the combined expression of these five genes emerged as the most powerful independent prognostic indicator associated with poor survival outcome compared to classical clinicopathological factors and any marker alone. In conclusion, our study identifies novel prognostic biomarkers for PAC, which await validation.

KIF11 Promotes Proliferation of Hepatocellular Carcinoma among Patients with Liver Cancers

BACKGROUND

Hepatocellular carcinoma (HCC) lacks effective treatments and has a poor prognosis. Therefore it is needed to develop more effective drug targets. Kinesin family member 11 (KIF11) has been reported to affect the progression of several cancers, and its high expression associates with the prognosis of patients. However, the relevant mechanisms of KIF11 in HCC progression have not been studied.

METHOD

Through the cancer genome atlas (TCGA) database and immunohistochemical (IHC) staining of patients' specimens, we determined that KIF11 was highly expressed in HCC tissues and associated with prognosis. We established a KIF11 stably depleted hepatoma cell line, through cell-cloning experiments and cell counting kit-8 (CCK-8) assays to detect the effects on proliferation in vitro. The role of KIF11 in promoting cell proliferation was verified in mice.

RESULT

The expression of KIF11 was negatively correlated with the overall survival (OS) and disease-free survival (DFS) and positively correlated with tumor size of HCC patients. KIF11 depletion inhibits cell proliferation and tumor growth in vitro and in vivo. Conclusion. KIF11 can be used as a positive correlation marker for HCC prognosis and served as a potential therapeutic target.

p21-activated kinase 6 controls mitosis and hepatocellular carcinoma progression by regulating Eg5

P21-activated kinases 6 (PAK6) associated with many fundamental cellular processes in cancer including cell-cell adhesion, migration and apoptosis. Here, we report a novel function of PAK6 in mitosis. Expression of PAK6 peaks in the M phase. Knockdown of PAK6 increases cell number in G2/M and promotes cell proliferation. PAK6 specifically colocalizes with Eg5 in the centrosome. Depletion of PAK6 results in multipolar spindle and a simultaneous upregulation of Eg5. Further, the PAK6 depletion-induced multiple spindle and cell cycle progression is reversed by knockdown of Eg5. These data suggest that PAK6 regulates spindle formation and cell cycle by regulating Eg5 expression. Additionally, expression of PAK6 is upregulated when Eg5 is downregulated or inhibited. Thus, PAK6 and Eg5 negatively inter-regulate each other. Significantly, the effect of PAK6 expression on the outcome of the HCC patients is controlled by Eg5 expression. Inhibition of Eg5 reverses PAK6 depletion-promoted cell invasion. Collectively, our data indicate that the inter-regulation between PAK6 and Eg5 might promote the progression of HCC.

Suppression of KIF22 Inhibits Cell Proliferation and Xenograft Tumor Growth in Tongue Squamous Cell Carcinoma

Background

Oral carcinoma is the sixth most common cancer and is a serious public health problem, and tongue squamous cell carcinoma (TSCC) is the most common type of oral carcinoma. Kinesin family member 22 (KIF22), also called as kinesin-like DNA binding protein (KID), is a microtubule-based motor protein and binds to both microtubules and chromosomes, transporting organelles, protein, and mRNA. This research aimed at investigating the prognostic significance of KIF22 in TSCC. Patients and Methods. This retrospective research collected 82 paired tissues with TSCC. KIF22 protein expression level was detected by immunohistochemical staining. Suppression of KIF22 with shRNA in CAL-27 and SCC-15 cells was to observe cell proliferation in vitro and xenograft tumor growth in vivo.

Results

In TSCC tissues, the protein expression level of KIF22 was increased and correlated with tumor stage, clinical stage, and lymphatic metastasis (P=0.013, P=0.013, P=0.013,

Conclusion

KIF22 might play an important role in the progression of TSCC and could serve as a therapeutic target for TSCC.

Suppression of KIF22 Inhibits Cell Proliferation and Xenograft Tumor Growth in Colon Cancer

Background: Kinesin family member 22 (KIF22) is known as a regulator of cell mitosis and cellular vesicle transport. The alterations of KIF22 are associated with a series of tumors; however, its possible role in the progression of colon cancer is still unclear. Materials and Methods: This retrospective research collected 82 paired tissues with colon cancer. KIF22 protein and mRNA expression levels were detected by immunohistochemistry assays and Immunoblot assays, respectively. Short hairpin RNA (shRNA) plasmids were used to suppress the expression of KIF22 in HCT116 and HT29 cells, and the silencing efficiencies of shRNA plasmids targeted KIF22 were detected by quantitative PCR assays and immunoblot assays. In addition, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assays and xenograft tumor growth assays were performed to observe cell proliferation in vitro and in vivo. Results: In human colon cancer tissues, the expression level of KIF22 was increased and correlated with clinical pathological features, including tumor stage and clinical stage (p = 0.034, and p = 0.015, respectively). Suppression of KIF22 inhibited cell proliferation and xenograft tumor growth. Conclusion: KIF22 might play an important role in the regulation of cell proliferation in colon cancer and might therefore serve as a promising therapeutic target.

The balance of forces generated by kinesins controls spindle polarity and chromosomal heterogeneity in tetraploid cells

Chromosomal instability, one of the most prominent features of tumour cells, causes aneuploidy. Tetraploidy is thought to be an intermediate on the path to aneuploidy, but the mechanistic relationship between the two states is poorly understood. Here, we show that spindle polarity (e.g., bipolarity or multipolarity) in tetraploid cells depends on the level of functional phospho-Eg5, a mitotic kinesin, localised at the spindle. Multipolar spindles are formed in cells with high levels of phospho-Eg5. This process is suppressed by inhibition of Eg5 or expression of a non-phosphorylatable Eg5 mutant, as well as by changing the balance between opposing forces required for centrosome separation. Tetraploid cells with high levels of functional Eg5 give rise to a heterogeneous aneuploid population via multipolar division, whereas those with low levels of functional Eg5 continue to undergo bipolar division and remain tetraploid. Furthermore, Eg5 expression levels correlate with ploidy status in tumour specimens. We provide a novel explanation for the tetraploid intermediate model: spindle polarity and subsequent tetraploid cell behaviour are determined by the balance of forces generated by mitotic kinesins at the spindle.

Non-canonical functions of the mitotic kinesin Eg5

Kinesins are widely expressed, microtubule-dependent motors that play vital roles in microtubule-associated cellular activities, such as cell division and intracellular transport. Eg5, also known as kinesin-5 or kinesin spindle protein, is a member of the kinesin family that contributes to the formation and maintenance of the bipolar mitotic spindle during cell division. Small-molecule compounds that inhibit Eg5 activity have been shown to impair spindle assembly, block mitotic progression, and possess anti-cancer activity. Recent studies focusing on the localization and functions of Eg5 in plants have demonstrated that in addition to spindle organization, this motor protein has non-canonical functions, such as chromosome segregation and cytokinesis, that have not been observed in animals. In this review, we discuss the structure, function, and localization of Eg5 in various organisms, highlighting the specific role of this protein in plants. We also propose directions for the future studies of novel Eg5 functions based on the lessons learned from plants.