Nek2 siRNA therapy using a portal venous port-catheter system for liver metastasis in pancreatic cancer

RNA nanomedicine in liver diseases

The remarkable impact of RNA nanomedicine during the COVID-19 pandemic has demonstrated the expansive therapeutic potential of this field in diverse disease contexts. In recent years, RNA nanomedicine targeting the liver has been paradigm-shifting in the management of metabolic diseases such as hyperoxaluria and amyloidosis. RNA nanomedicine has significant potential in the management of liver diseases, where optimal management would benefit from targeted delivery, doses titrated to liver metabolism, and personalized therapy based on the specific site of interest. In this review, we discuss in-depth the different types of RNA and nanocarriers used for liver targeting along with their specific applications in metabolic dysfunction-associated steatotic liver disease, liver fibrosis, and liver cancers. We further highlight the strategies for cell-specific delivery and future perspectives in this field of research with the emergence of small activating RNA, circular RNA, and RNA base editing approaches.

The NEK family of serine/threonine kinases as a biomarker for cancer

Cancer is defined by unrestrained cell proliferation due to impaired protein activity. Cell cycle-related proteins are likely to play a role in human cancers, including proliferation, invasion, and therapeutic resistance. The serine/threonine NEK kinases are the part of Never In Mitosis A Kinases (NIMA) family, which are less explored kinase family involved in the cell cycle, checkpoint regulation, and cilia biology. They comprise of eleven members, namely NEK1, NEK2, NEK3, NEK4, NEK5, NEK6, NEK7, NEK8, NEK9, NEK10, and NEK11, located in different cellular regions. Recent research has shown the role of NEK family in various cancers by perversely expressing. Therefore, this review aimed to provide a systematic account of our understanding of NEK kinases; structural details; and its role in the cell cycle regulation. Furthermore, we have comprehensively reviewed the NEK kinases in terms of their expression and regulation in different cancers. Lastly, we have emphasized on some of the potential NEK inhibitors reported so far.

Overexpression of NIMA related kinase 2 in multiple myeloma and its relevance with disease features and prognosis to bortezomib treatment

WHAT IS KNOWN AND OBJECTIVE

NIMA related kinase 2 (NEK2) promotes the malignant transformation and enhances the chemoresistance to proteasome inhibitor in multiple myeloma (MM) cell lines. The current study aimed to further investigate its correlation with clinical features and responsiveness to bortezomib treatment in MM patients.

METHODS

Totally, 76 MM patients and 30 health donors (HDs) were enrolled to collect bone marrow plasma cells for NEK2 detection using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Meanwhile, NEK2 siRNA was transfected into the RPMI-8226 and KMS-11 cells, subsequently their cell viability was evaluated using Cell Counting Kit-8 reagent after treatment with different doses of bortezomib.

RESULTS AND DISCUSSION

NEK2 expression was higher in MM patients compared with HDs (Z = -5.123, p < 0.001). Besides, elevated NEK2 expression was associated with the occurrence of the bone lesion (χ²  = 4.610, p = 0.032) and t (4; 14) (χ²  = 3.971, p = 0.046). Additionally, elevated NEK2 expression was correlated with declined objective response rate (ORR) (χ²  = 4.808, p = 0.028), but not with complete response (CR) (χ²  = 2.341, p = 0.126). More importantly, elevated NEK2 expression was correlated with shorter progression-free survival (PFS) (χ²  = 8.352, p = 0.039), but not with overall survival (OS) (χ²  = 5.624, p = 0.131), What is more, NEK2 silence decreased the cell viability under bortezomib treatment and the inhibitory concentration (IC₅₀ ) value of bortezomib in RPMI-8226 and KMS-11 cell lines (all p < 0.05).

WHAT IS NEW AND CONCLUSION

NEK2 overexpression links with occurrence of bone lesion, t (4; 14), and poor prognosis to bortezomib treatment in MM patients.

CENPA regulates tumor stemness in lung adenocarcinoma

Lung adenocarcinoma is a malignant and fatal respiratory disease. However, due to its complex pathogenesis and poorly effective therapeutic options, accurate early diagnosis and prognosis remain elusive. Now, there is increasing evidence that tumor stem cells are involved in tumorigenesis, metastasis, relapse, resistance to chemotherapy and radiotherapy and are one of the reasons why tumors cannot be cured. The mRNA expression based-stemness index (mRNAsi) is a parameter obtained by Malta and his colleagues applying innovative one-class logistic regression machine learning algorithm (OCLR) on mRNA expression in normal stem cells and their progeny. It is a valid evaluation parameter and is currently employed to evaluate the degree of differentiation of a certain tumor. In this study, we first used WGCNA and the software Cytoscape to obtain key modules and hub genes. We then applied LASSO regression analysis to calculate the genes in the key module to obtain a six-gene risk model. Moreover, the accuracy of this model was validated. Finally, we took the intersection of hub genes and risk genes and validated CENPA as both a tumor stemness regulator and a tumor prognostic factor in lung cancer.

In Mitosis You Are Not: The NIMA Family of Kinases in Aspergillus, Yeast, and Mammals

The Never in mitosis gene A (NIMA) family of serine/threonine kinases is a diverse group of protein kinases implicated in a wide variety of cellular processes, including cilia regulation, microtubule dynamics, mitotic processes, cell growth, and DNA damage response. The founding member of this family was initially identified in Aspergillus and was found to play important roles in mitosis and cell division. The yeast family has one member each, Fin1p in fission yeast and Kin3p in budding yeast, also with functions in mitotic processes, but, overall, these are poorly studied kinases. The mammalian family, the main focus of this review, consists of 11 members named Nek1 to Nek11. With the exception of a few members, the functions of the mammalian Neks are poorly understood but appear to be quite diverse. Like the prototypical NIMA, many members appear to play important roles in mitosis and meiosis, but their functions in the cell go well beyond these well-established activities. In this review, we explore the roles of fungal and mammalian NIMA kinases and highlight the most recent findings in the field.

Pre-Clinical and Clinical Applications of Small Interfering RNAs (siRNA) and Co-Delivery Systems for Pancreatic Cancer Therapy

Pancreatic cancer (PC) is one of the leading causes of death and is the fourth most malignant tumor in men. The epigenetic and genetic alterations appear to be responsible for development of PC. Small interfering RNA (siRNA) is a powerful genetic tool that can bind to its target and reduce expression level of a specific gene. The various critical genes involved in PC progression can be effectively targeted using diverse siRNAs. Moreover, siRNAs can enhance efficacy of chemotherapy and radiotherapy in inhibiting PC progression. However, siRNAs suffer from different off target effects and their degradation by enzymes in serum can diminish their potential in gene silencing. Loading siRNAs on nanoparticles can effectively protect them against degradation and can inhibit off target actions by facilitating targeted delivery. This can lead to enhanced efficacy of siRNAs in PC therapy. Moreover, different kinds of nanoparticles such as polymeric nanoparticles, lipid nanoparticles and metal nanostructures have been applied for optimal delivery of siRNAs that are discussed in this article. This review also reveals that how naked siRNAs and their delivery systems can be exploited in treatment of PC and as siRNAs are currently being applied in clinical trials, significant progress can be made by translating the current findings into the clinical settings.

Preparation of an anti-NEK2 monoclonal antibody and its application in liver cancer

Background

Never in mitosis gene-A (NIMA)-related expressed kinase 2 (NEK2) is a serine/threonine protein kinase regulated by the cell cycle. The purpose of this study was to obtain NEK2 protein to prepare an anti-NEK2 monoclonal antibody (mAb) and explore the application of the anti-NEK2 mAb of therapeutic and diagnostic in hepatocellular carcinoma (HCC).

Results

The NEK2 gene sequence was cloned from the normal liver cell line HL7702, and the full-length NEK2 gene sequence was cloned into the prokaryotic expression vector pET30a and transformed into Escherichia coli BL21 (DE3) cells. The recombinant fusion protein was obtained under optimized conditions and injected in BALB/c mice to prepare an anti-NEK2 mAb. By screening, we obtained a stable hybridoma cell line named 3A3 that could stably secrete anti-NEK2 mAb. Anti-NEK2 3A3 mAb was purified from ascites fluid. The isotype was IgG1, and the affinity constant (K_aff) was 6.0 × 10⁸ L/mol. Western blot, indirect enzyme-linked immunosorbent assay (iELISA), immunofluorescence and immunocytochemical analyses showed that the mAb could specifically recognize the NEK2 protein. MTT assays showed that the mAb 3A3 could inhibit the proliferation of HCC cells. KEGG pathway analysis showed that NEK2 might affected pathways of the cell cycle. Moreover, NEK2-related genes were mainly enriched in the S and G2 phases and might act as tumor-promoting genes by regulating the S/G2 phase transition of HCC cells.

Conclusions

An anti-NEK2 mAb with high potency, high affinity and high specificity was prepared by prokaryotic expression system in this study and may be used in the establishment of ELISA detection kits and targeted treatment of liver cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12896-021-00717-3.

Silencing of Nek2 suppresses the proliferation, migration and invasion and induces apoptosis of breast cancer cells by regulating ERK/MAPK signaling

Breast cancer is a frequent cancer among women. The current study investigated the biological functions of Nek2 in breast cancer and its possible mechanism. The mRNA expression of Nek2 in breast epithelial cells and eight breast cancer cell lines was detected by qRT-PCR. Silencing Nek2 was transfected into MDA-MB-231 and MCF7 cells to examine its roles in the viability, migration, invasion, cell colony, apoptosis and cell cycle of the breast cancer cells by performing CCK-8, wound scratch, Transwell, clone formation and flow cytometry assays, respectively. The expressions of related genes were detected using qRT-PCR and Western blot. MAPK pathway agonist IGF (insulin-like growth factor-1) was added into MDA-MB-231 and MCF7 cells and then cell viability was examined. Nek2 expression was frequently up-regulated in breast cancer cell lines, and silencing Nek2 significantly inhibited the viability, cell migration, invasion and clone formation, promoted cell apoptosis of MDA-MB-231 and MCF7 cells, and arrested cell cycle in G0/G1 phase. Furthermore, knocking down Nek2 decreased the mRNA and protein expressions of Bcl-2, CyclinB1 and CyclinD1, and increased Bax and p27 expressions. Moreover, knocking down Nek2 inhibited the phosphorylation of ERK and p38, and almost completely reversed the expression of p-ERK increased by IGF, but Nek2 knockdown had no obvious effect on p-p38. The inhibitory effect of Nek2 silencing on the cell viability was mainly realized by the inhibition of ERK/MAPK signaling. Nek2 plays an important role in the regulation of the progression of breast cancer in vitro probably through regulating the ERK/MAPK signaling.

Involvement of NEK2 and its interaction with NDC80 and CEP250 in hepatocellular carcinoma

BACKGROUND

NEK2 has an established involvement in hepatocellular carcinoma (HCC) but the roles of NEK2 and its interacting proteins in HCC have not been systematically explored.

METHODS

This study examined NEK2 and its interacting proteins in HCC based on multiple databases.

RESULTS

NEK2 mRNA was highly expressed in HCC tissues compared with normal liver tissues. The survival of HCC patients with high NEK2 mRNA expression was shorter than those with low expression. MAD1L1, CEP250, MAPK1, NDC80, PPP1CA, PPP1R2 and NEK11 were the interacting proteins of NEK2. Among them, NDC80 and CEP250 were the key interacting proteins of NEK2. Mitotic prometaphase may be the key pathway that NEK2 and its interacting proteins contributed to HCC pathogenesis. NEK2, NDC80 and CEP250 mRNAs were highly expressed in HCC tissues compared with normal liver tissues. The mRNA levels of NEK2 were positively correlated with those of NDC80 or CEP250. Univariate regression showed that NEK2, NDC80 and CEP250 mRNA expressions were significantly associated with HCC patients' survival. Multivariate regression showed that NDC80 mRNA expression was an independent predictor for HCC patients' survival. Methylations and genetic alterations of NEK2, NDC80 and CEP250 were observed in HCC samples. The alterations of NEK2, NDC80 and CEP250 genes were co-occurrence. Patients with high mRNA expression and genetic alterations of NEK2, NDC80 and CEP250 had poor prognosis.

CONCLUSIONS

NEK2 and its interacting proteins NDC80 and CEP250 play important roles in HCC development and progression and thus may be potentially used as biomarkers and therapeutic targets of HCC.

Checking NEKs: Overcoming a Bottleneck in Human Diseases

In previous years, several kinases, such as phosphoinositide 3-kinase (PI3K), mammalian target of rapamycin (mTOR), and extracellular-signal-regulated kinase (ERK), have been linked to important human diseases, although some kinase families remain neglected in terms of research, hiding their relevance to therapeutic approaches. Here, a review regarding the NEK family is presented, shedding light on important information related to NEKs and human diseases. NEKs are a large group of homologous kinases with related functions and structures that participate in several cellular processes such as the cell cycle, cell division, cilia formation, and the DNA damage response. The review of the literature points to the pivotal participation of NEKs in important human diseases, like different types of cancer, diabetes, ciliopathies and central nervous system related and inflammatory-related diseases. The different known regulatory molecular mechanisms specific to each NEK are also presented, relating to their involvement in different diseases. In addition, important information about NEKs remains to be elucidated and is highlighted in this review, showing the need for other studies and research regarding this kinase family. Therefore, the NEK family represents an important group of kinases with potential applications in the therapy of human diseases.

Role of E2Fs and mitotic regulators controlled by E2Fs in the epithelial to mesenchymal transition

The epithelial-to-mesenchymal transition (EMT) is a complex cellular process in which epithelial cells acquire mesenchymal properties. EMT occurs in three biological settings: development, wound healing and fibrosis, and tumor progression. Despite occurring in three independent biological settings, EMT signaling shares some molecular mechanisms that allow epithelial cells to de-differentiate and acquire mesenchymal characteristics that confer cells invasive and migratory capacity to distant sites. Here we summarize the molecular mechanism that delineates EMT and we will focus on the role of E2 promoter binding factors (E2Fs) in EMT during tumor progression. Since the E2Fs are presently undruggable due to their control in numerous pivotal cellular functions and due to the lack of selectivity against individual E2Fs, we will also discuss the role of three mitotic regulators and/or mitotic kinases controlled by the E2Fs (NEK2, Mps1/TTK, and SGO1) in EMT that can be useful as drug targets.

Impact statement

The study of the epithelial to mesenchymal transition (EMT) is an active area of research since it is one of the early intermediates to invasion and metastasis—a state of the cancer cells that ultimately kills many cancer patients. We will present in this review that besides their canonical roles as regulators of proliferation, unregulated expression of the E2F transcription factors may contribute to cancer initiation and progression to metastasis by signaling centrosome amplification, chromosome instability, and EMT. Since our discovery that the E2F activators control centrosome amplification and mitosis in cancer cells, we have identified centrosome and mitotic regulators that may represent actionable targets against EMT and metastasis in cancer cells. This is impactful to all of the cancer patients in which the Cdk/Rb/E2F pathway is deregulated, which has been estimated to be most cancer patients with solid tumors.

Role of non-coding RNA in pancreatic cancer

Pancreatic cancer is a malignant disease that develops rapidly and carries a poor prognosis. Currently, surgery is the only radical treatment. Non-coding RNAs (ncRNAs) are protein-free RNAs produced by genome transcription; they play important roles in regulating gene expression, participating in epigenetic modification, cell proliferation, differentiation and reproduction. ncRNAs also play key roles in the development of cancer; microRNA (miRNA) and long non-coding RNA (lncRNA) may lead the way to new treatments for pancreatic cancer. miRNAs are short-chain ncRNAs (19–24 nt) that inhibit the degradation of protein translation or their target gene mRNAs to regulate gene expression. lncRNAs contain >200 nt of ncRNA and play important regulatory roles in a number of malignant tumors, in terms of tumor cell proliferation, apoptosis, invasion and distant metastasis. lncRNAs can be exploited for the diagnosis and treatment of pancreatic cancer and have substantial prospects for clinical application. Nevertheless, the molecular mechanism of their regulation and function, as well as the significance of other ncRNAs, such as piwi-interacting RNA, in the pathogenesis of pancreatic cancer, are largely unknown. In this review, the structures of ncRNAs with various classifications, as well as the functions and important roles of ncRNAs in the diagnosis and treatment of pancreatic cancer are reviewed.

Survival Analysis of Multi-Omics Data Identifies Potential Prognostic Markers of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most common and among the deadliest of pancreatic cancers. Its 5-year survival is only ∼8%. Pancreatic cancers are a heterogeneous group of diseases, of which PDAC is particularly aggressive. Like many other cancers, PDAC also starts as a pre-invasive precursor lesion (known as pancreatic intraepithelial neoplasia, PanIN), which offers an opportunity for both early detection and early treatment. Even advanced PDAC can benefit from prognostic biomarkers. However, reliable biomarkers for early diagnosis or those for prognosis of therapy remain an unfulfilled goal for PDAC. In this study, we selected 153 PDAC patients from the TCGA database and used their clinical, DNA methylation, gene expression, and micro-RNA (miRNA) and long non-coding RNA (lncRNA) expression data for multi-omics analysis. Differential methylations at about 12,000 CpG sites were observed in PDAC tumor genomes, with about 61% of them hypermethylated, predominantly in the promoter regions and in CpG-islands. We correlated promoter methylation and gene expression for mRNAs and identified 17 genes that were previously recognized as PDAC biomarkers. Similarly, several genes (B3GNT3, DMBT1, DEPDC1B) and lncRNAs (PVT1, and GATA6-AS) are strongly correlated with survival, which have not been reported in PDAC before. Other genes such as EFR3B, whose biological roles are not well known in mammals are also found to strongly associated with survival. We further identified 406 promoter methylation target loci associated with patients survival, including known esophageal squamous cell carcinoma biomarkers, cg03234186 (ZNF154), and cg02587316, cg18630667, and cg05020604 (ZNF382). Overall, this is one of the first studies that identified survival associated genes using multi-omics data from PDAC patients.

Importance of protein flexibility on molecular recognition: modeling binding mechanisms of aminopyrazine inhibitors to Nek2

NIMA-related kinase 2 (Nek2) plays a significant role in cell cycle regulation, and overexpression of Nek2 has been observed in several types of carcinoma, suggesting it is a potential target for cancer therapy. In this study, we attempted to gain more insight into the binding mechanisms of a series of aminopyrazine inhibitors of Nek2 through multiple molecular modeling techniques, including molecular docking, molecular dynamics (MD) simulations and free energy calculations. The simulation results showed that the induced fit docking and ensemble docking based on multiple protein structures yield better predictions than conventional rigid receptor docking, highlighting the importance of incorporating receptor flexibility into the accurate predictions of the binding poses and binding affinities of Nek2 inhibitors. Additionally, we observed that the Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) calculations did not show better performance than the docking scoring to rank the binding affinities of the studied inhibitors, suggesting that MM/GBSA is system-dependent and may not be the best choice for the Nek2 systems. Moreover, the detailed information on protein-ligand binding was characterized by the MM/GBSA free energy decomposition, and a number of derivatives with improved docking scores were designed. It is expected that our study can provide valuable information for the future rational design of novel and potent inhibitors of Nek2.

NEK2 promotes hepatocellular carcinoma migration and invasion through modulation of the epithelial-mesenchymal transition

Never in mitosis gene-A (NIMA)-related expressed kinase 2 (NEK2) has been recently reported to play a role in tumor progression, drug resistance and tumorigenesis. However, little is known about the effects of NEK2 in hepatocellular carcinoma (HCC) metastasis and the underlying mechanism. NEK2 expression levels were examined by immunochemistry, qRT-PCR and western blot analyses in HCC cell lines and HCC tissues. A Transwell assay was used to determine the migration and invasion capacity of NEK2-silenced or NEK2-overexpressing HCC cells. Cell proliferation was investigated by MTT [(3-(4,5)-dimethylthiazol(-z-y1)-3,5-di-phenytetrazolium bromide] assay. The expression levels of epithelial-mesenchymal transition (EMT) markers in NEK2-silenced or NEK2-overexpressing HCC cells were examined by western blot analyses and qRT-PCR. The correlations between NEK2 expression and clinicopathological characteristics were further analyzed. Gene microarray was further used to analyze the effect of NEK2 expression on downstream cell signals. Our study showed that NEK2 was overexpressed in human HCC (37.84%; 98/259). NEK2 overexpression was significantly associated with liver non-capsulation and predicted poor survival outcomes in HCC patients after hepatectomy. In addition, NEK2 significantly enhanced HCC cell invasive ability. Mechanistically, we found that the epithelial-mesenchymal transition (EMT) plays a pivotal role in the NEK2-mediated promotion of HCC cell invasion. Furthermore, we provided evidence that signaling through the Wnt, NF-κB, focal adhesion, VEGF, Hippo and p53 pathways may be downstream of NEK2. Our findings highlight the importance of NEK2 in HCC metastasis and suggest that NEK2 is a reliable prognostic marker for HCC patients after hepatectomy.

MicroRNA-128 promotes apoptosis in lung cancer by directly targeting NIMA-related kinase 2

Background

MicroRNA‐128 (miR‐128) serves as a regulator by inducing cancer cell apoptosis, differentiation, the epithelial‐to‐mesenchymal transition process, and tumor growth by mediating different targets. NIMA‐related kinase 2 (NEK2) is aberrantly expressed in lung cancer. The miR‐128/NEK2 pathway has been reported to predict prognosis in colorectal cancer; however, the determination of a relationship between miR‐128 and NEK2 in lung cancer has remained elusive. We explored the association between miR‐128 and NEK2 in lung cancer.

Methods

MiR‐128 and NEK2 expression were examined in 15 lung cancer tissues by real time‐PCR. Lung cancer SK‐MES‐1 cells were transfected with miR‐128 mimic, an inhibitor or a negative control. MiR‐128 and NEK2 expression levels were detected using quantitative real time‐PCR and Western blot. SK‐MES‐1 cell apoptosis was performed by flow cytometry.

Results

Compared to adjacent non‐tumor tissues, miR‐128 was downregulated and NEK2 was upregulated in 15 lung cancer tissues. Lung cancer SK‐MES‐1 cells transfected with miR‐128 mimic induced a higher apoptotic rate than those transfected with the negative control. Dual luciferase assay further confirmed that NEK2 was a direct target of miR‐128 in lung cancer, and transfection with miR‐128 mimic could decrease the NEK2 protein level while the miR‐128 inhibitor increased NEK2 expression. Finally, the apoptotic effect of lung cancer cells induced by miR‐128 mimic could be reversed by NEK2 overexpression.

Conclusions

NEK2 was regulated by miR‐128 in lung cancer and miR‐128 induced lung cancer cell apoptosis by mediating NEK2 expression.

Nek2 siRNA therapy using a portal venous port-catheter system for liver metastasis in pancreatic cancer

Nek2 (NIMA-related kinase 2) is a serine-threonine kinase and human homolog of the mitotic regulator NIMA of Aspergillus nidulan. We reported the efficiency of Nek2 siRNA in several cancer xenograft models using cholangiocarcinoma, breast cancer and colorectal cancer. Pancreatic cancer is difficult to treat due to its rapid progression and resistance to chemotherapy. Novel treatments are urgently required to improve survival in pancreatic cancer, and siRNA are a promising therapeutic option. However, finding an in vivo drug delivery system of siRNA remains a major problem for clinical application. In this study, the overexpression of Nek2 was identified in pancreatic cancer cell lines. Nek2 siRNA inhibited tumor growth in a subcutaneous xenograft mouse model of pancreatic cancer, prolonged the survival time in an intraperitoneal xenograft mouse model and efficiently prevented the progression of liver metastasis using a portal venous port-catheter system. Taken together, Nek2 is an effective therapeutic target in pancreatic cancer. An adequate delivery system is considered important in treating advanced pancreatic cancer, such as peritoneal dissemination and liver metastasis. Further investigations are required on the safety and side effects of the portal venous port-catheter system. We hope that Nek2 siRNA will be a novel therapeutic strategy for pancreatic cancer with liver metastasis and peritoneal dissemination.