Inhibition of Aurora A enhances radiosensitivity in selected lung cancer cell lines

Research progress on the relationship between AURKA and tumorigenesis: the neglected nuclear function of AURKA

AURKA is a threonine or serine kinase that needs to be activated by TPX2, Bora and other factors. AURKA is located on chromosome 20 and is amplified or overexpressed in many human cancers, such as breast cancer. AURKA regulates some basic cellular processes, and this regulation is realized via the phosphorylation of downstream substrates. AURKA can function in either the cytoplasm or the nucleus. It can promote the transcription and expression of oncogenes together with other transcription factors in the nucleus, including FoxM1, C-Myc, and NF-κB. In addition, it also sustains carcinogenic signaling, such as N-Myc and Wnt signaling. This article will focus on the role of AURKA in the nucleus and its carcinogenic characteristics that are independent of its kinase activity to provide a theoretical explanation for mechanisms of resistance to kinase inhibitors and a reference for future research on targeted inhibitors.

Suppression of NSCLC progression via the co-administration of Danusertib, an AURK inhibitor, and KRIBB11, an HSF1 inhibitor

Aurora kinase (AURK) and heat shock factor 1 (HSF1) are commonly overexpressed in non-small cell lung cancer (NSCLC), correlating with poor prognosis. This study aims to assess the therapeutic potential of combining the Danusertib (Danu, AURK inhibitor) and KRIBB11 (HSF1 inhibitor) for NSCLC treatment. The effects of this combination were investigated in A549 cells and a tumor xenograft mouse model. The findings demonstrate that concurrent administration of Danu and KRIBB11 effectively impedes cell proliferation, induces apoptosis, and triggers G2/M cell cycle arrest. Moreover, the combination treatment upregulates pro-apoptotic proteins (Cleaved-caspase3, Cleaved-PARP, and Bax) while downregulating anti-apoptotic proteins (Bcl-2), as well as G2/M-related proteins (CDC2 and cyclin B1). Additionally, the combination treatment elevates reactive oxygen species (ROS) levels, decreases mitochondrial membrane potential, and activates the DNA damage pathway. Interestingly, we discovered that the PI3K/AKT pathway is involved in mediating the effects of both Danu and KRIBB11. Furthermore, the combination treatment inhibits tumor growth and AKT signaling in the xenograft mouse model, increases levels of the tumor tissue oxidation product malondialdehyde (MDA), and induces DNA damage. To summarize, a potential therapeutic approach for NSCLC may involve dual inhibition of AURK and HSF1, resulting in the downregulation of the PI3K/AKT signaling pathway, and the activation of ROS-mediated mitochondrial and DNA damage pathways.

Clinical translation for targeting DNA damage repair in non-small cell lung cancer: a review

Despite significant advancements in screening, diagnosis, and treatment of non-small cell lung cancer (NSCLC), it remains the primary cause of cancer-related deaths globally. DNA damage is caused by the exposure to exogenous and endogenous factors and the correct functioning of DNA damage repair (DDR) is essential to maintain of normal cell circulation. The presence of genomic instability, which results from defective DDR, is a critical characteristic of cancer. The changes promote the accumulation of mutations, which are implicated in cancer cells, but these may be exploited for anti-cancer therapies. NSCLC has a distinct genomic profile compared to other tumors, making precision medicine essential for targeting actionable gene mutations. Although various treatment options for NSCLC exist including chemotherapy, targeted therapy, and immunotherapy, drug resistance inevitably arises. The identification of deleterious DDR mutations in 49.6% of NSCLC patients has led to the development of novel target therapies that have the potential to improve patient outcomes. Synthetic lethal treatment using poly (ADP-ribose) polymerase (PARP) inhibitors is a breakthrough in biomarker-driven therapy. Additionally, promising new compounds targeting DDR, such as ATR, CHK1, CHK2, DNA-PK, and WEE1, had demonstrated great potential for tumor selectivity. In this review, we provide an overview of DDR pathways and discuss the clinical translation of DDR inhibitors in NSCLC, including their application as single agents or in combination with chemotherapy, radiotherapy, and immunotherapy.

Combined Aurora Kinase A and CHK1 Inhibition Enhances Radiosensitivity of Triple-Negative Breast Cancer Through Induction of Apoptosis and Mitotic Catastrophe Associated With Excessive DNA Damage

PURPOSE

There is an urgent need for biomarkers and new actionable targets to improve radiosensitivity of triple-negative breast cancer (TNBC) tumors. We characterized the radiosensitizing effects and underlying mechanisms of combined Aurora kinase A (AURKA) and CHK1 inhibition in TNBC.

METHODS AND MATERIALS

Different TNBC cell lines were treated with AURKA inhibitor (AURKAi, MLN8237) and CHK1 inhibitor (CHK1i, MK8776). Cell responses to irradiation (IR) were then evaluated. Cell apoptosis, DNA damage, cell cycle distribution, and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and Phosphoinositide 3-Kinase (PI3K) pathways were evaluated in vitro. Transcriptomic analysis was performed to facilitate the identification of potential biomarkers. Xenograft and immunohistochemistry were carried out to investigate the radiosensitizing effects of dual inhibition in vivo. Finally, the prognostic effect of CHEK1/AURKA in TNBC samples in the The Cancer Genome Atlas (TCGA) database and our center were analyzed.

RESULTS

AURKAi (MLN8237) induced overexpression of phospho-CHK1 in TNBC cells. The addition of MK8776 (CHK1i) to MLN8237 greatly reduced cell viability and increased radiosensitivity compared with either the control or MLN8237 alone in vitro. Mechanistically, dual inhibition resulted in inducing excessive DNA damage by prompting G2/M transition to cells with defective spindles, leading to mitotic catastrophe and induction of apoptosis after IR. We also observed that dual inhibition suppressed the phosphorylation of ERK, while activation of ERK with its agonist or overexpression of active ERK1/2 allele could attenuate the apoptosis induced by dual inhibition with IR. Additionally, dual inhibition of AURKA and CHK1 synergistically enhanced radiosensitivity in MDA-MB-231 xenografts. Moreover, we detected that both CHEK1 and AURKA were overexpressed in patients with TNBC and negatively correlated with patient survival.

CONCLUSIONS

Our findings suggested that AURKAi in combination with CHK1i enhanced TNBC radiosensitivity in preclinical models, potentially providing a novel strategy of precision treatment for patients with TNBC.

The Role of Aurora B Kinase in Normal and Cancer Cells

Aurora kinases are essential players in mammalian cell division. These kinases are involved in the regulation of spindle dynamics, microtubule-kinetochore interactions, and chromosome condensation and orientation during mitosis. At least three members of the Aurora family - Aurora kinases A, B, and C - have been identified in mammals. Aurora B is essential for maintaining genomic stability and normal cell division. Mutations and dysregulation of this kinase are implicated in tumor initiation and progression. In this review, we discuss the functions of Aurora B, the relationship between increased Aurora B activity and carcinogenesis, and the prospects for the use of Aurora B kinase inhibitors in antitumor therapy.

A genomic score to predict local control among patients with brain metastases managed with radiation

BACKGROUND

Clinical predictors of local recurrence following radiation among patients with brain metastases (BrM) provide limited explanatory power. We developed a DNA-based signature of radiotherapeutic efficacy among patients with BrM to better characterize recurrence risk.

METHODS

We identified 570 patients with 1487 BrM managed with whole-brain (WBRT) or stereotactic radiation therapy at Brigham and Women's Hospital/Dana-Farber Cancer Institute (2013-2020) for whom next-generation sequencing panel data (OncoPanel) were available. Fine/Gray's competing risks regression was utilized to compare local recurrence on a per-metastasis level among patients with versus without somatic alterations of likely biological significance across 84 genes. Genes with a q-value ≤ 0.10 were utilized to develop a "Brain-Radiation Prediction Score" ("Brain-RPS").

RESULTS

Genomic alterations in 11 (ATM, MYCL, PALB2, FAS, PRDM1, PAX5, CDKN1B, EZH2, NBN, DIS3, and MDM4) and 2 genes (FBXW7 and AURKA) were associated with decreased or increased risk of local recurrence, respectively (q-value ≤ 0.10). Weighted scores corresponding to the strength of association with local failure for each gene were summed to calculate a patient-level RPS. On multivariable Fine/Gray's competing risks regression, RPS [1.66 (1.44-1.91, P < .001)], metastasis-associated edema [1.60 (1.16-2.21), P = .004], baseline size [1.02 (1.01-1.03), P < .001] and receipt of WBRT without local therapy [4.04 (2.49-6.58), P < .001] were independent predictors of local failure.

CONCLUSIONS

We developed a genomic score to quantify local recurrence risk following brain-directed radiation. To the best of our knowledge, this represents the first study to systematically correlate DNA-based alterations with radiotherapeutic outcomes in BrM. If validated, Brain-RPS has potential to facilitate clinical trials aimed at genome-based personalization of radiation in BrM.

Unravelling hub genes as potential therapeutic targets in lung cancer using integrated transcriptomic meta-analysis and in silico approach

Lung cancer (LC) is the leading cause of cancer-related deaths worldwide. Smoking has been identified as the main contributing cause of the disease's development. The study aimed to identify the key genes in small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), the two major types of LC. Meta-analysis was performed with two datasets GSE74706 and GSE149507 obtained from Gene Expression Omnibus (GEO). Both the datasets comprised samples from cancerous and adjacent non-cancerous tissues. Initially, 633 differentially expressed genes (DEGs) were identified. To understand the underlying molecular mechanism of the identified genes, pathway enrichment, gene ontology (GO) and protein-protein interaction (PPI) analyses were done. A total of 9 hub genes were identified which were subjected to mutation study analysis in LC patients using cBioPortal. These   9 genes (i.e. AURKA, AURKB, KIF23, RACGAP1, KIF2C, KIF20A, CENPE, TPX2 and PRC1) have shown overexpression in LC patients and can be explored as potential candidates for prognostic biomarkers. TPX2 reported a maximum mutation of 4 % . This was followed with high throughput screening and docking analysis to identify the potential drug candidates following competitive inhibition of the AURKA-TPX2 complex. Four compounds, CHEMBL431482, CHEMBL2263042, CHEMBL2385714, and CHEMBL1206617 were identified. The results signify that the selected 9 genes can be explored as biomarkers in disease prognosis and targeted therapy. Also, the identified 4 compounds can be further analyzed as promising therapeutic candidates.Communicated by Ramaswamy H. Sarma.

A novel risk model of three gefitinib-related genes FBP1, SBK1 and AURKA is related to the immune microenvironment and is predicting prognosis of lung adenocarcinoma patients

PURPOSE

Gefitinib, an anticancer drug, has been reported to potentially improve the prognosis of patients with lung adenocarcinoma (LUAD). This study aims to investigate the roles and mechanisms of Gefitinib.

METHODS

The effects of Gefitinib on the growth and migration of LUAD cells were assessed using various methods, including CCK-8, flow cytometry, wound healing, and Transwell assays. To analyze the function and mechanisms of the differentially expressed Gefitinib target genes (GTGs), data from the TCGA database were utilized. Kaplan-Meier survival and ROC analysis identified prognostic-related GTGs and constructed a prognostic nomogram in LUAD. Consensus clustering, COX analysis and survival analysis evaluated the relationship between GTGs and the prognosis of LUAD patients. The mechanisms of the risk model involved LUAD progression, and the relationship between the risk model and immune microenvironment were investigated.

RESULTS

Gefitinib could inhibit proliferation, migration and invasion and promote cell apoptosis. 84 DEGTGs were involved in RAS, MAPK, ERBB pathways. The DEGTGs (FBP1, SBK1, and AURKA) were the independent risk factors for dismal prognosis of LUAD patients and were used to establish risk model and nomogram. Gefitinib could promote the expression of FBP1 and inhibit the expression of SBK1 and AURKA. High-risk LUAD patients had the dismal prognosis, and the high-risk score group was significantly associated with the immune microenvironment.

CONCLUSION

FBP1, SBK1, and AURKA are prognostic risk factors, and the risk model and nomogram of FBP1, SBK1 and AURKA are associated with dismal prognosis and immune cell infiltration, and have huge prospects for application in evaluating the prognosis in LUAD.

Systematic analysis of transcriptome signature for improving outcomes in lung adenocarcinoma

PURPOSE

The updated guidelines highlight gene expression-based multigene panel as a critical tool to assess overall survival (OS) and improve treatment for lung adenocarcinoma (LUAD) patients. Nevertheless, genome-wide expression signatures are still limited in real clinical utility because of insufficient data utilization, a lack of critical validation, and inapposite machine learning algorithms.

METHODS

2330 primary LUAD samples were enrolled from 11 independent cohorts. Seventy-six algorithm combinations based on ten machine learning algorithms were applied. A total of 108 published gene expression signatures were collected. Multiple pharmacogenomics databases and resources were utilized to identify precision therapeutic drugs.

RESULTS

We comprehensively developed a robust machine learning-derived genome-wide expression signature (RGS) according to stably OS-associated RNAs (OSRs). RGS was an independent risk element and remained robust and reproducible power by comparing it with general clinical parameters, molecular characteristics, and 108 published signatures. RGS-based stratification possessed different biological behaviors, molecular mechanisms, and immune microenvironment patterns. Integrating multiple databases and previous studies, we identified that alisertib was sensitive to the high-risk group, and RITA was sensitive to the low-risk group.

CONCLUSION

Our study offers an appealing platform to screen dismal prognosis LUAD patients to improve clinical outcomes by optimizing precision therapy.

Aurora B Inhibitors as Cancer Therapeutics

The Aurora kinases (A, B, and C) are a family of three isoform serine/threonine kinases that regulate mitosis and meiosis. The Chromosomal Passenger Complex (CPC), which contains Aurora B as an enzymatic component, plays a critical role in cell division. Aurora B in the CPC ensures faithful chromosome segregation and promotes the correct biorientation of chromosomes on the mitotic spindle. Aurora B overexpression has been observed in several human cancers and has been associated with a poor prognosis for cancer patients. Targeting Aurora B with inhibitors is a promising therapeutic strategy for cancer treatment. In the past decade, Aurora B inhibitors have been extensively pursued in both academia and industry. This paper presents a comprehensive review of the preclinical and clinical candidates of Aurora B inhibitors as potential anticancer drugs. The recent advances in the field of Aurora B inhibitor development will be highlighted, and the binding interactions between Aurora B and inhibitors based on crystal structures will be presented and discussed to provide insights for the future design of more selective Aurora B inhibitors.

Emerging roles of Aurora-A kinase in cancer therapy resistance

Aurora kinase A (Aurora-A), a serine/threonine kinase, plays a pivotal role in various cellular processes, including mitotic entry, centrosome maturation and spindle formation. Overexpression or gene-amplification/mutation of Aurora-A kinase occurs in different types of cancer, including lung cancer, colorectal cancer, and breast cancer. Alteration of Aurora-A impacts multiple cancer hallmarks, especially, immortalization, energy metabolism, immune escape and cell death resistance which are involved in cancer progression and resistance. This review highlights the most recent advances in the oncogenic roles and related multiple cancer hallmarks of Aurora-A kinase-driving cancer therapy resistance, including chemoresistance (taxanes, cisplatin, cyclophosphamide), targeted therapy resistance (osimertinib, imatinib, sorafenib, etc.), endocrine therapy resistance (tamoxifen, fulvestrant) and radioresistance. Specifically, the mechanisms of Aurora-A kinase promote acquired resistance through modulating DNA damage repair, feedback activation bypass pathways, resistance to apoptosis, necroptosis and autophagy, metastasis, and stemness. Noticeably, our review also summarizes the promising synthetic lethality strategy for Aurora-A inhibitors in RB1, ARID1A and MYC gene mutation tumors, and potential synergistic strategy for mTOR, PAK1, MDM2, MEK inhibitors or PD-L1 antibodies combined with targeting Aurora-A kinase. In addition, we discuss the design and development of the novel class of Aurora-A inhibitors in precision medicine for cancer treatment.

A Review of Radiation-Induced Alterations of Multi-Omic Profiles, Radiation Injury Biomarkers, and Countermeasures

Increasing utilization of nuclear power enhances the risks associated with industrial accidents, occupational hazards, and the threat of nuclear terrorism. Exposure to ionizing radiation interferes with genomic stability and gene expression resulting in the disruption of normal metabolic processes in cells and organs by inducing complex biological responses. Exposure to high-dose radiation causes acute radiation syndrome, which leads to hematopoietic, gastrointestinal, cerebrovascular, and many other organ-specific injuries. Altered genomic variations, gene expression, metabolite concentrations, and microbiota profiles in blood plasma or tissue samples reflect the whole-body radiation injuries. Hence, multi-omic profiles obtained from high-resolution omics platforms offer a holistic approach for identifying reliable biomarkers to predict the radiation injury of organs and tissues resulting from radiation exposures. In this review, we performed a literature search to systematically catalog the radiation-induced alterations from multi-omic studies and radiation countermeasures. We covered radiation-induced changes in the genomic, transcriptomic, proteomic, metabolomic, lipidomic, and microbiome profiles. Furthermore, we have covered promising multi-omic biomarkers, FDA-approved countermeasure drugs, and other radiation countermeasures that include radioprotectors and radiomitigators. This review presents an overview of radiation-induced alterations of multi-omics profiles and biomarkers, and associated radiation countermeasures.

Unweaving the mitotic spindle: A focus on Aurora kinase inhibitors in lung cancer

Lung cancer is one of the most aggressive malignancies, classified into two major histological subtypes: non-small cell lung cancer (NSCLC), that accounts for about 85% of new diagnosis, and small cell lung cancer (SCLC), the other 15%. In the case of NSCLC, comprehensive genome sequencing has allowed the identification of an increasing number of actionable targets, which have become the cornerstone of treatment in the advanced setting. On the other hand, the concept of oncogene-addiction is lacking in SCLC, and the only innovation of the last 30 years has been the introduction of immune checkpoint inhibitors in extensive stage disease. Dysregulation of cell cycle is a fundamental step in carcinogenesis, and Aurora kinases (AURKs) are a family of serine/threonine kinases that play a crucial role in the correct advance through the steps of the cycle. Hyperexpression of Aurora kinases is a common protumorigenic pathway in many cancer types, including NSCLC and SCLC; in addition, different mechanisms of resistance to anticancer drugs rely on AURK expression. Hence, small molecule inhibitors of AURKs have been developed in recent years and tested in several malignancies, with different results. The aim of this review is to analyze the current evidences of AURK inhibition in lung cancer, starting from preclinical rationale to finish with clinical trials available up to now.

The role of radiotherapy-related autophagy genes in the prognosis and immune infiltration in lung adenocarcinoma

Background

There is a close relationship between radiotherapy and autophagy in tumors, but the prognostic role of radiotherapy-related autophagy genes (RRAGs) in lung adenocarcinoma (LUAD) remains unclear.

Methods

Data used in the current study were extracted from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Weighted gene co-expression network analysis (WGCNA) was executed to recognize module genes associated with radiotherapy. The differentially expressed genes (DEGs) between different radiotherapy response groups were filtered via edgeR package. The differentially expressed radiotherapy-related autophagy genes (DERRAGs) were obtained by overlapping the module genes, DEGs, and autophagy genes (ATGs). Then, prognostic autophagy genes were selected by Cox analyses, and a risk model and nomogram were subsequently built. Gene Set Enrichment Analysis (GSEA) and single-sample Gene Set Enrichment Analysis (ssGSEA) were performed to investigate potential mechanisms through which prognostic autophagy signatures regulate LUAD. Radiotherapy-resistant cell lines (A549IR and PC9IR) were established after exposure to hypo-fractionated irradiation. Ultimately, mRNA expression was validated by quantitative real-time PCR (qRT-PCR), and relative protein levels were measured in different cell lines by western blot.

Results

A total of 11 DERRAGs were identified in LUAD. After Cox analyses, SHC1, NAPSA, and AURKA were filtered as prognostic signatures in LUAD. Then, the risk score model was constructed using the prognostic signatures, which had a good performance in predicting the prognosis, as evidenced by receiver operating characteristics curves. Furthermore, Cox regression analyses demonstrated that risk score was deemed as an independent prognostic factor in LUAD. Moreover, GSEA and ssGSEA results revealed that prognostic RRAGs may regulate LUAD by modulating the immune microenvironment and affecting cell proliferation. The colony formation assay showed that the radiosensitivity of radiation-resistant cell lines was lower than that of primary cells. The western blot assay found that the levels of autophagy were elevated in the radiotherapy-resistant cell lines. Moreover, the expression of DERRAGs (SHC1, AURKA) was higher in the radiotherapy-resistant cells than in primary cells.

Conclusion

Our study explored the role of RRAGs in the prognosis of LUAD and identified three biomarkers. The findings enhanced the understanding of the relationship between radiotherapy, autophagy, and prognosis in LUAD and provided potential therapeutic targets for LUAD patients.

Network Pharmacology and Comparative Transcriptome Reveals Biotargets and Mechanisms of Curcumol Treating Lung Adenocarcinoma Patients With COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has led to 4,255,892 deaths worldwide. Although COVID-19 vaccines are available, mutant forms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have reduced the effectiveness of vaccines. Patients with cancer are more vulnerable to COVID-19 than patients without cancer. Identification of new drugs to treat COVID-19 could reduce mortality rate, and traditional Chinese Medicine(TCM) has shown potential in COVID-19 treatment. In this study, we focused on lung adenocarcinoma (LUAD) patients with COVID-19. We aimed to investigate the use of curcumol, a TCM, to treat LUAD patients with COVID-19, using network pharmacology and systematic bioinformatics analysis. The results showed that LUAD and patients with COVID-19 share a cluster of common deregulated targets. The network pharmacology analysis identified seven core targets (namely, AURKA, CDK1, CCNB1, CCNB2, CCNE1, CCNE2, and TTK) of curcumol in patients with COVID-19 and LUAD. Clinicopathological analysis of these targets demonstrated that the expression of these targets is associated with poor patient survival rates. The bioinformatics analysis further highlighted the involvement of this target cluster in DNA damage response, chromosome stability, and pathogenesis of LUAD. More importantly, these targets influence cell-signaling associated with the Warburg effect, which supports SARS-CoV-2 replication and inflammatory response. Comparative transcriptomic analysis on in vitro LUAD cell further validated the effect of curcumol for treating LUAD through the control of cell cycle and DNA damage response. This study supports the earlier findings that curcumol is a potential treatment for patients with LUAD and COVID-19.

RBL2/DREAM-mediated repression of the Aurora kinase A/B pathway determines therapy responsiveness and outcome in p53 WT NSCLC

Wild-type p53 is a stress-responsive transcription factor and potent tumor suppressor. P53 activates or represses genes involved in cell cycle progression or apoptosis in order to arrest the cell cycle or induce cell death. Transcription repression by p53 is indirect and requires repressive members of the RB-family (RB1, RBL1, RBL2) and formation of repressor complexes of RB1-E2F and RBL1/RBL2-DREAM. Many aurora kinase A/B (AURKA/B) pathway genes are repressed in a p53-DREAM-dependent manner. We found heightened expression of RBL2 and reduced expression of AURKA/B pathway genes is associated with improved outcomes in p53 wild-type but not p53 mutant non-small cell lung cancer (NSCLC) patients. Knockdown of p53, RBL2, or the DREAM component LIN37 increased AURKA/B pathway gene expression and reduced paclitaxel and radiation toxicity in NSCLC cells. In contrast, pharmacologic inhibition of AURKA/B or knockdown of AURKA/B pathway components increased paclitaxel and IR sensitivity. The results support a model in which p53-RBL2-DREAM-mediated repression of the AURKA/B pathway contributes to tumor suppression, improved tumor therapy responses, and better outcomes in p53 wild-type NSCLCs.

The cell cycle-related genes RHAMM, AURKA, TPX2, PLK1, and PLK4 are associated with the poor prognosis of breast cancer patients

Breast cancer is the third most common type of cancer diagnosed. Cell cycle is a complex but highly organized and controlled process, in which normal cells sense mitogenic growth signals that instruct them to enter and progress through their cell cycle. This process culminates in cell division generating two daughter cells with identical amounts of genetic material. Uncontrolled proliferation is one of the hallmarks of cancer. In this study, we analyzed the expression of the cell cycle-related genes receptor for hyaluronan (HA)-mediated motility (RHAMM), AURKA, TPX2, PLK1, and PLK4 and correlated them with the prognosis in a collective of 3952 breast cancer patients. A high messenger RNA expression of all studied genes correlated with a poor prognosis. Stratifying the patients according to the expression of hormonal receptors, we found that in patients with estrogen and progesterone receptor-positive and human epithelial growth factor receptor 2-negative tumors, and Luminal A and Luminal B tumors, the expression of the five analyzed genes correlates with worse survival. qPCR analysis of a panel of breast cancer cell lines representative of major molecular subtypes indicated a predominant expression in the luminal subtype. In vitro experiments showed that radiation influences the expression of the five analyzed genes both in luminal and triple-negative model cell lines. Functional analysis of MDA-MB-231 cells showed that small interfering RNA knockdown of PLK4 and TPX2 and pharmacological inhibition of PLK1 had an impact on the cell cycle and colony formation. Looking for a potential upstream regulation by microRNAs, we observed a differential expression of RHAMM, AURKA, TPX2, PLK1, and PLK4 after transfecting the MDA-MB-231 cells with three different microRNAs. Survival analysis of miR-34c-5p, miR-375, and miR-142-3p showed a different impact on the prognosis of breast cancer patients. Our study suggests that RHAMM, AURKA, TPX2, PLK1, and PLK4 can be used as potential targets for treatment or as a prognostic value in breast cancer patients.

Repression of the AURKA-CXCL5 axis induces autophagic cell death and promotes radiosensitivity in non-small-cell lung cancer

Aurora kinase A (AURKA) regulates apoptosis and autophagy in various diseases and has shown promising clinical effects. Nevertheless, the complex regulatory mechanism of AURKA and autophagy in non-small-cell lung cancer (NSCLC) radiosensitivity remains to be elucidated. Here, we showed that AURKA was upregulated in NSCLC cell lines and tissues and that AURKA overexpression was significantly related to a poor prognosis, tumor stage and lymph node metastasis in NSCLC. Interestingly, AURKA expression was significantly increased after 8Gy radiotherapy. Silencing of AURKA enhanced radiosensitivity and impaired migration and invasion in vivo and in vitro. Mechanistically, we determined that CXCL5, a member of the chemokine family, was a key downstream effector of AURKA, and the phenotype induced by AURKA silencing was partly due to CXCL5 inhibition. We further demonstrated that the AURKA-CXCL5 axis played an essential role in NSCLC autophagy and that the activation of cytotoxic autophagy attenuated the malignant biological behavior of NSCLC cells mediated by AURKA-CXCL5. In general, we revealed the role of the AURKA-CXCL5 axis and autophagy in regulating the sensitivity of NSCLC cells to radiotherapy, which may provide potential therapeutic targets and new strategies for combatting NSCLC resistance to radiotherapy.

Alpelisib and radiotherapy treatment enhances Alisertib-mediated cervical cancer tumor killing

Human papilloma virus (HPV) is the main causative agent in cervical cancers. High-risk HPV cancers, including cervical cancer, are driven by major HPV oncogene, E6 and E7, which promote uncontrolled cell growth and genomic instability. We have previously shown that the presence of HPV E7 sensitizes cells to inhibition of aurora kinases (AURKs), which regulates the control of cell entry into and through mitosis. Such treatment is highly effective at eliminating early tumors and reducing large, late tumors. In addition, the presence of HPV oncogenes also sensitizes cells to inhibition of phosphoinositide 3-kinases (PI3Ks), a family of enzymes involved in cellular functions such as cell growth and proliferation. Using MLN8237 (Alisertib), an oral, selective inhibitor of AURKs, we investigated whether Alisertib treatment can improve tumor response when combined with either radiotherapy (RT) treatment or with a PI3K inhibitor, BYL719 (Alpelisib). Indeed, both RT and Alpelisib significantly improved Alisertib-mediated tumor killing, and the promising achieved results warrant further development of these combinations, and potentially translating them to the clinics.

Biological functions of therapy-induced senescence in cancer

Therapy-induced cellular senescence is a state of stable growth arrest induced by common cancer treatments such as chemotherapy and radiation. In an oncogenic context, therapy-induced senescence can have different consequences. By blocking cellular proliferation and by facilitating immune cell infiltration, it functions as tumor suppressive mechanism. By fueling the proliferation of bystander cells and facilitating metastasis, it acts as a tumor promoting factor. This dual role is mainly attributed to the differential expression and secretion of a set of pro-inflammatory cytokines and tissue remodeling factors, collectively known as the Senescence-Associated Secretory Phenotype (SASP). Here, we describe cell-autonomous and non-cell-autonomous mechanisms that senescent cells activate in response to chemotherapy and radiation leading to tumor suppression and tumor promotion. We present the current state of knowledge on the stimuli that affect the activation of these opposing mechanisms and the effect of senescent cells on their micro-environment eg. by regulating the functions of immune cells in tumor clearance as well as strategies to eliminate senescent tumor cells before exerting their deleterious side-effects.

Comprehensive transcriptomic analysis identifies novel regulators of lung adenocarcinoma

Lung adenocarcinoma (LA) is a subtype of lung cancer that accounts for about 40% of all lung cancers. Analysis of molecular mechanisms controlling this cancer can help scientists to detect, control and treat LA. Here, a microarray dataset (GSE118370) containing six normal lung (NL) and six LA samples was screened using GEO2R to find differentially expressed genes (DEGs). Then, DAVID, KEGG and ChEA were used to analyze DEGs-related gene ontology, pathways and transcription factors (TFs), respectively. The Protein-protein interaction network for DEGs and TFs was constructed by STRING and Cytoscape. To find microRNAs and metabolites associated with DEGs, miRTarBase and HMDB were used, respectively. It was found that 350 genes were upregulated and 608 genes were downregulated in LA. The upregulated genes or LA-related gens were enriched in biological process and pathways such as extracellular matrix disassembly and p53 signaling pathway, whereas the downregulated genes or NL-related genes were enriched in cell adhesion and cell-surface receptor signaling pathway. ESR1, KIF18B, BIRC5, CHEK1, CCNB1 and AURKA were determined as hub genes for LA. FOXA1 and TFAP2A had the highest number of connectivity in LA-related TFs. hsa-miR-192-5p and hsa-miR-215-5p could target the highest number of LA-related genes. Metabolite analysis showed that Estrone and NADPH were among the top ten metabolites associated with LA-related genes. Taken together, LA-related genes, especially the hub genes, TFs, and metabolites might be used as novel markers for LA, as well as for diagnosis and guiding therapeutic strategies of LA.

Promising Therapy in Lung Cancer: Spotlight on Aurora Kinases

Simple Summary

Lung cancer has remained one of the major causes of death worldwide. Thus, a more effective treatment approach is essential, such as the inhibition of specific cancer-promoting molecules. Aurora kinases regulate the process of mitosis—a process of cell division that is necessary for normal cell proliferation. Dysfunction of these kinases can contribute to cancer formation. In this review, we present studies indicating the implication of Aurora kinases in tumor formation, drug resistance, and disease prognosis. The effectivity of using Aurora kinase inhibitors in the pre-clinical and clinical investigations has proven their therapeutic potential in the setting of lung cancer. This work may provide further information to broaden the development of anticancer drugs and, thus, improve the conventional lung cancer management.

Abstract

Despite tremendous efforts to improve the treatment of lung cancer, prognosis still remains poor; hence, the search for efficacious therapeutic option remains a prime concern in lung cancer research. Cell cycle regulation including mitosis has emerged as an important target for cancer management. Novel pharmacological agents blocking the activities of regulatory molecules that control the functional aspects of mitosis such as Aurora kinases are now being investigated. The Aurora kinases, Aurora-A (AURKA), and Aurora B (AURKB) are overexpressed in many tumor entities such as lung cancer that correlate with poor survival, whereby their inhibition, in most cases, enhances the efficacy of chemo-and radiotherapies, indicating their implication in cancer therapy. The current knowledge on Aurora kinase inhibitors has increasingly shown high potential in ensuing targeted therapies in lung malignancies. In this review, we will briefly describe the biology of Aurora kinases, highlight their oncogenic roles in the pre-clinical and clinical studies in lung cancer and, finally, address the challenges and potentials of Aurora kinases to improve the therapy of this malignancy.

The role of Aurora-A in human cancers and future therapeutics

Aurora-A is a mitotic serine/threonine-protein kinase and an oncogene. In normal cells, Aurora-A appears from G2 phase and localizes at the centrosome, where it participates in centrosome replication, isolation and maturation. Aurora-A also maintains Golgi apparatus structure and spindle assembly. Aurora-A undergoes ubiquitination-mediated degradation after the cell division phase. Aurora-A is abnormally expressed in tumor cells and promotes cell proliferation by regulating mitotic substrates, such as PP1, PLK1, TPX2, and LAST2, and affects other molecules through a non-mitotic pathway to promote cell invasion and metastasis. Some molecules in tumor cells also indirectly act on Aurora-A to regulate tumor cells. Aurora-A also mediates resistance to chemotherapy and radiotherapy and is involved in tumor immunotherapy. Clinical trials of Aurora-A molecular inhibitors are currently underway, and clinical transformation is just around the corner.

Aurora kinases and DNA damage response

It is well established that Aurora kinases perform critical functions during mitosis. It has become increasingly clear that the Aurora kinases also perform a myriad of non-mitotic functions including DNA damage response. The available evidence indicates that inhibition Aurora kinase A (AURKA) may contribute to the G₂ DNA damage checkpoint through AURKA's functions in PLK1 and CDC25B activation. Both AURKA and Aurora kinase B (AURKB) are also essential in mitotic DNA damage response that guard against DNA damage-induced chromosome segregation errors, including the control of abscission checkpoint and prevention of micronuclei formation. Dysregulation of Aurora kinases can trigger DNA damage in mitosis that is sensed in the subsequent G₁ by a p53-dependent postmitotic checkpoint. Aurora kinases are themselves linked to the G₁ DNA damage checkpoint through p53 and p73 pathways. Finally, several lines of evidence provide a connection between Aurora kinases and DNA repair and apoptotic pathways. Although more studies are required to provide a comprehensive picture of how cells respond to DNA damage, these findings indicate that both AURKA and AURKB are inextricably linked to pathways guarding against DNA damage. They also provide a rationale to support more detailed studies on the synergism between small-molecule inhibitors against Aurora kinases and DNA-damaging agents in cancer therapies.

Weighted Gene Coexpression Network Analysis of Features That Control Cancer Stem Cells Reveals Prognostic Biomarkers in Lung Adenocarcinoma

Purpose We aimed to identify new prognostic biomarkers of lung adenocarcinoma (LUAD) based on cancer stem cell theory.

Materials and Methods: RNA-seq and microarray data were obtained with clinical information downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Weighted gene coexpression network analysis (WGCNA) was applied to identify significant module and hub genes. The hub genes were validated via microarray data from GEO, and a prognostic signature with prognostic hub genes was constructed.

Results LUAD patients enrolled from TCGA had a higher mRNA expression-based stemness index (mRNAsi) in tumor tissue than in adjacent normal tissue. Some clinical features and prognoses were found to be highly correlated with mRNAsi. WGCNA found that the green module and blue module were the most significant modules related to mRNAsi; 50 key genes were identified in the green module and were enriched mostly in the cell cycle, chromosome segregation, chromosomal region and microtubule binding. Six hub genes were revealed through the protein-protein interaction (PPI) network and Molecular Complex Detection (MCODE) plugin of Cytoscape software. Based on external verification with the GEO database, these six genes are not only expressed at different levels in LUAD and normal tissues but also associated with different clinical features. In addition, the construction of a prognostic signature with three hub genes showed high predictive value.

Conclusion mRNAsi-related biomarkers may suggest a new potential treatment strategy for LUAD.

The Multi-Modal Effect of the Anti-fibrotic Drug Pirfenidone on NSCLC

Although immune checkpoint and targeted therapies offer remarkable benefits for lung cancer treatment, some patients do not qualify for these regimens or do not exhibit consistent benefit. Provided that lung cancer appears to be driven by transforming growth factor beta signaling, we investigated the single drug potency of Pirfenidone, an approved drug for the treatment of lung fibrosis. Five human lung cancer cell lines and one murine line were investigated for transforming growth factor beta inhibition via Pirfenidone by using flow cytometry, In-Cell western analysis, proliferation assays as well as comprehensive analyses of the transcriptome with subsequent bioinformatics analysis. Overall, Pirfenidone induced cell cycle arrest, down-regulated SMAD expression and reduced proliferation in lung cancer. Furthermore, cell stress pathways and pro-apoptotic signaling may be mediated by reduced expression of Survivin. A murine subcutaneous model was used to assess the in vivo drug efficacy of Pirfenidone and showed reduced tumor growth and increased infiltration of T cells and NK cells. This data warrant further clinical evaluation of Pirfenidone with advanced non-small cell lung cancer. The observed in vitro and in vivo effects point to a substantial benefit for using Pirfenidone to reactivate the local immune response and possible application in conjunction with current immunotherapies.