Aurora Kinase Inhibitors Research Articles

Chemical genetics analysis suggests the involvement of Aurora kinase and MAPKs in aluminum-induced malate secretion in Arabidopsis.

Chemical genetics is a multidisciplinary research method. In this study, it is used to screen compounds that promote aluminum-induced malate secretion in Arabidopsis thaliana. Inhibition of p38 mitogen-activated protein kinase (p38 MAPK; LY2228820) significantly increased the transcription of Arabidopsis thaliana aluminum-activated malate transporter 1 (AtALMT1) and sensitive to proton rhizotoxicity 1 (STOP1)-regulated genes, multidrug and toxic compound extrusion and aluminum sensitive 3, but not AtSTOP1 and the Al-biomarker genes At3g28510, At5g13320, suggesting that LY2228820 increased the early expression of STOP1-regulated genes without affecting AtSTOP1 expression. Inhibition of p38 MAPK (LY2228820) and Aurora A (MLN8237) increased aluminum-activated malate transport via AtALMT1, suggesting that both MLN8237 and LY2228820 interfere with AtALMT1 activity. An increase in root elongation was also observed in Arabidopsis after applying compounds LY2228820 and MLN8237. Thus, both LY2228820 and MLN8237 may play important roles in alleviating the inhibitory effects of aluminum on roots.

Reprogramming cellular senescence in the tumor microenvironment augments cancer immunotherapy through multifunctional nanocrystals.

Harnessing the immunogenic potential of senescent tumor cells provides an opportunity to remodel tumor microenvironment (TME) and boost antitumor immunity. However, this potential needs to be sophisticatedly wielded to avoid additional immunosuppressive capacity of senescent cells. Our study shows that blocking the JAK2/STAT3 pathway enhances immunogenic efficacy of Aurora kinase inhibitor alisertib (Ali)-induced senescence by reducing immunosuppressive senescence-associated secretory phenotype (SASP) while preserving immunogenic SASP. Hypothesizing that SASP reprogramming with Ali and JAK2 inhibitor ruxolitinib (Rux) will benefit cancer immunotherapy, we create nanoparticulate crystals (Ali-Rux) composed of Ali and Rux with a fully active pharmaceutical ingredient. Immunization with Ali-Rux-orchestrated senescent cells promotes stronger activation of antigen-presenting cells, enhancing antitumor immune surveillance. This approach remodels the TME by increasing CD8+ T cell and NK recruitment and activation while decreasing MDSCs. Combined with PD-L1 blockade, Ali-Rux elicits a durable antitumor immune response, suggesting the TME reshaping approach as a potential cancer immunotherapy.

AURKA inhibition shows promise as a therapeutic strategy for ARID1A-mutant colorectal cancer

PurposeMutations in ARID1A frequently occur in colorectal cancer (CRC) cells. However, there are currently no clinical treatment options specifically addressing this aberration. The preliminary in vitro experiments revealed a synthetic lethal interaction between ARID1A and Aurora kinase A (AURKA) in colorectal cancer (CRC) cells.MethodsWe collected samples from 80 CRC patients and evaluated the efficacy of AURKA inhibitor (AURKAi) using the ATP-tumor chemosensitivity assay (ATP-TCA) on untreated ARID1A-proficient (ARID1A +) and ARID1A-deficient (ARID1A-) CRC patient samples. In addition, we validated this result by a clonogenic assay. Additionally, we examined the effects of AURKA inhibitors on cell cycle progression and apoptosis in ARID1A + and ARID1A- CRC patient samples using flow cytometry.ResultsThe results showed that AURKAi selectively inhibited the growth of ARID1A- CRC cells. Furthermore, AURKA inhibitors significantly increased G2/M arrest and induced apoptosis in ARID1A- cells.ConclusionWe believe that AURKAi hold promise as potential therapeutics for ARID1A mutation colorectal cancer patients.

Differential regulation of expression of the protein kinases DYRK1A and DYRK1B in cancer cells

The protein kinases DYRK1A and DYRK1B are pivotal regulators of cell cycle progression by promoting cell cycle exit into quiescence. DYRK1B appears to play a more important role in cancer cell quiescence than DYRK1A, as evidenced by its overexpression or copy number variations in human tumour samples. Nonetheless, the stimuli driving DYRK1B upregulation and the potential divergence in expression patterns between DYRK1A and DYRK1B remain largely elusive. In the present study, we scrutinized the regulatory pathways modulating DYRK1B expression relative to DYRK1A in PANC-1 and A549 cancer cell lines across varying conditions. Serum deprivation, pharmacological mTOR inhibition and increased cell density resulted in the differential upregulation of DYRK1B compared to DYRK1A. We then aimed to assess the role of protein kinases MST1 and MST2, which are key transmitters of cell density dependent effects. Unexpectedly, exposure to the MST1/2 inhibitor XMU-MP-1 resulted in increased DYRK1B levels in A549 cells. Further investigation into the off-target effects of XMU-MP-1 unveiled the inhibition of Aurora kinases (AURKA and AURKB) as a potential causative factor. Consistently, AURK inhibitors VX-680 (tozasertib), MLN8237 (alisertib), AZD1152-HQPA (barasertib) resulted in the upregulation of DYRK1B expression in A549 cells. In summary, our findings indicate that the expression of DYRK1A and DYRK1B is differentially regulated in cancer cells and reveal that the kinase inhibitor XMU-MP-1 increases DYRK1B expression likely through off target inhibition of Aurora kinases.

Pyrrole-Indoline-2-Ones as Aurora Kinase Inhibitors: Pharmacophore Modeling, 3D QSAR Studies and Molecular Dynamics

Pyrrole-Indoline-2-Ones as Aurora Kinase Inhibitors: Pharmacophore Modeling, 3D QSAR Studies and Molecular Dynamics

Repurposed AT9283 triggers anti-tumoral effects by targeting MKK3 oncogenic functions in Colorectal Cancer

BackgroundColorectal cancer (CRC) is the third most common type of cancer and the second leading cause of cancer-related deaths worldwide, with a survival rate near to 10% when diagnosed at an advanced stage. Hence, the identification of new molecular targets to design more selective and efficient therapies is urgently required. The Mitogen activated protein kinase kinase 3 (MKK3) is a dual-specificity threonine/tyrosine protein kinase that, activated in response to cellular stress and inflammatory stimuli, regulates a plethora of biological processes. Previous studies revealed novel MKK3 roles in supporting tumor malignancy, as its depletion induces autophagy and cell death in cancer lines of different tumor types, including CRC. Therefore, MKK3 may represent an interesting new therapeutic target in advanced CRC, however selective MKK3 inhibitors are currently not available.MethodsThe study involved transcriptomic based drug repurposing approach and confirmatory assays with CRC lines, primary colonocytes and a subset of CRC patient-derived organoids (PDO). Investigations in vitro and in vivo were addressed.ResultsThe repurposing approach identified the multitargeted kinase inhibitor AT9283 as a putative compound with MKK3 depletion-mimicking activities. Indeed, AT9283 drops phospho- and total-MKK3 protein levels in tested CRC models. Likely the MKK3 silencing, AT9283 treatment: i) inhibited cell proliferation promoting autophagy and cell death in tested CRC lines and PDOs; ii) resulted well-tolerated by CCD-18Co colonocytes; iii) reduced cancer cell motility inhibiting CRC cell migration and invasion; iv) inhibited COLO205 xenograft tumor growth. Mechanistically, AT9283 abrogated MKK3 protein levels mainly through the inhibition of aurora kinase A (AURKA), impacting on MKK3/AURKA protein–protein interaction and protein stability therefore uncovering the relevance of MKK3/AURKA crosstalk in sustaining CRC malignancy in vitro and in vivo.ConclusionOverall, we demonstrated that the anti-tumoral effects triggered by AT9283 treatment recapitulated the MKK3 depletion effects in all tested CRC models in vitro and in vivo, suggesting that AT9283 is a repurposed drug. According to its good tolerance when tested with primary colonocytes (CCD-18CO), AT9283 is a promising drug for the development of novel therapeutic strategies to target MKK3 oncogenic functions in late-stage and metastatic CRC patients.

AURKA Activates FOXO3a to Form a Positive Feedback Loop in the Proliferation and Migration of Keloid Fibroblasts.

Objective: Keloids are benign fibroproliferative disorders with invasive growth exceeding the wound boundary. Aurora kinase A (AURKA) is a serine/threonine kinase highly expressed in various tumors, facilitating tumor growth and invasion. Currently, the role of AURKA in keloid remains unclear. Approach: Fibroblasts were isolated from keloid and normal skin samples. AURKA was evaluated by qPCR, Western blot, and immunohistochemistry. Transcriptome sequencing and dual-luciferase reporter assays were applied to figure out targets of AURKA. Following expression alteration and MLN8237 (an AURKA kinase inhibitor, AKI) treatment, phenotypical experiments were conducted to clarify biological functions of AURKA along with its target, and to probe into the clinical potential of AURKA inhibition. Results: AURKA was upregulated in keloid tissues and fibroblasts. Forkhead box O 3a (FOXO3a) was verified as a downstream of AURKA. Further experiments demonstrated that AURKA transactivated FOXO3a by binding to FOXO3a, while FOXO3a directly transactivated AURKA. Functionally, AURKA and FOXO3a cooperated in enhancing the proliferation and migration of keloid fibroblasts via protein kinase B (AKT) phosphorylation. Although MLN8237 weakened the proliferation and migration in keloid fibroblasts, the transactivation of AURKA on FOXO3a was independent of kinase activity. Innovation: This study reveals that AURKA and FOXO3a compose a transactivation loop in enhancing the proliferative and migrative properties of keloid fibroblasts, and proposes AURKA as a promising target. Conclusion: AURKA/FOXO3a loop promotes the proliferation and migration of keloid fibroblasts via AKT signaling. Despite the anti-keloid effects of AKIs, AURKA acts as a transcription factor independently of kinase activity, deepening our understanding on AKI insensitivity.

Aurora Kinase A Inhibition Potentiates Platinum and Radiation Cytotoxicity in Non-Small-Cell Lung Cancer Cells and Induces Expression of Alternative Immune Checkpoints.

Despite major advances in non-small-cell lung cancer (NSCLC) treatment, the five-year survival rates for patients with non-oncogene-driven tumors remain low, necessitating combinatory approaches to improve outcomes. Our prior high-throughput RNAi screening identified Aurora kinase A (AURKA) as a potential key player in cisplatin resistance. In this study, we investigated AURKA's role in platinum and radiation sensitivity in multiple NSCLC cell lines and xenograft mouse models, as well as its effect on immune checkpoints, including PD-L1, B7x, B7-H3, and HHLA2. Of 94 NSCLC patient tumor specimens, 91.5% tested positive for AURKA expression, with 34% showing moderate-to-high levels. AURKA expression was upregulated following cisplatin treatment in NSCLC cell lines PC9 and A549. Both AURKA inhibition by alisertib and inducible AURKA knockdown potentiated the cytotoxic effects of cisplatin and radiation, leading to tumor regression in doxycycline-inducible xenograft mice. Co-treated cells exhibited increased DNA double-strand breaks, apoptosis, and senescence. Additionally, AURKA inhibition alone by alisertib increased PD-L1 and B7-H3 expression. In conclusion, our study demonstrates that AURKA inhibition enhances the efficacy of platinum-based chemotherapy in NSCLC cells and modulates the expression of multiple immune checkpoints. Therefore, combinatory regimens with AURKA inhibitors should be strategically designed and further studied within the evolving landscape of chemo-immunotherapy.

16 Linking VHL and SETD2 in a common oncogenic pathway that converges on the mitoticspindle

Abstract Background Loss of chromosome 3p is a landmark event in clear cell renal cell carcinoma (ccRCC) that results in mono-allelic loss of VHL (von Hippel Lindau) and SETD2 (Set-domain containing 2) (and other tumor suppressors co-located on 3p). Second hits in VHL inactivate this key tumor suppressor initiating tumor progression. SETD2, a histone methyltransferase, was previously shown to have a dual function in methylating both histones and microtubules, thereby contributing to both the histone and tubulin codes. Methylation by SETD2 on microtubules occurs at the mitotic spindle and is essential for normal mitosis and cytokinesis, with loss of SETD2 acting as a strong driver of apoptosis. This raises a conundrum of how cancer cells survive early mono-allelic loss of SETD2, escaping cell death. Methods Using biochemical kinase assays and mass spectrometry we have identified SETD2 as a substrate for AURKA. In addition, we have used immunoblotting and immunofluorescence assays to probe phosphorylation on SETD2 and the impact of phosphorylation of SETD2 both on its chromatin and cytoskeleton targets. Results We have identified the mitotic kinase, Aurora kinase A (AURKA), as a regulator of SETD2. Our data uncover SETD2 as a unique substrate for phosphorylation by AURKA, with mass spectrometry identifying serine 2080 (S2080) as the site of phosphorylation on SETD2. We found phosphorylation of SETD2 by AURKA at S2080 contributes to its methyltransferase (i.e. enzymatic) activity on microtubules but does not impact chromatin methylation on H3K36 which remains unaltered. We show that VHL regulates SETD2 via AURKA, and loss of phosphorylation on SETD2 results in mitotic defects and genomic instability. Importantly, we demonstrate that inhibition of AURKA is synthetic lethal in the setting of VHL and SETD2 deficiency. Conclusions AURKA expression levels are high in VHL-null cells resulting from an inability of VHL to target AURKA for degradation and our data now highlight a direct link between VHL and SETD2, two tumor suppressors believed to independently drive RCC pathogenesis. In summary, our data reveal a tumor-specific vulnerability linked to mitotic fragility that can be precisely targeted to ultimately drive mitotic catastrophe. DOD CDMRP Funding: yes

Green Synthesis of Zinc Oxide NPs as a New Catalyst for the Synthesis of Imidazo[2,1-b]quinazoline Derivatives with Docking Validation as Aurora Kinase (AKI-001) Inhibitors

Abstract: As natural capping reagents, flaxseed gel, caprylic/capric triglyceride, aloe vera, and propylene glycol were utilized in the synthesis of ZnO-NPs in the current study. The synthesized ZnO NPs structure was characterized by Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FT-IR), and X-ray Diffraction (XRD). The prepared ZnO-NPs were used as an efficient catalyst for the production of a new series of fused polynuclear heterocyclic system-based imidazoquinazoline by multicomponent reaction. The reaction was initiated by mixing 2-aminobenzimidazole, aryl/hetaryl aldehydes, and betanaphthol under solvent-free conditions at 60-70°C in the presence of a catalytic amount of the synthesized ZnO-NPs. As demonstrated by molecular docking, the prepared ligands (4, 7, 8, 9, and 11) exhibited outstanding validation as aurora kinase inhibitors in comparison to AKI-001, the prototype pentacyclic inhibitor.

Clinical analysis of 10 cases with subcutaneous panniculitis-like T-cell lymphoma and tissue AURKA expression.

Due to its rarity, subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is often misdiagnosed as benign panniculitis, and there are no standardized treatment guidelines for SPTCL. Aurora kinase A (AURKA) plays a regulatory role in both mitosis and meiosis. Cells treated with an AURKA inhibitor showed severe mitotic delay, which triggered apoptosis. Ten cases of SPTCL were collected in this study, and immunohistochemistry was performed to detect AURKA expression in the skin tissues of these cases. Control groups were set as follows: 1) 10 cases of inflammatory panniculitis; 2) 9 healthy individuals. Fisher's exact test was used to compare the positive rates of AURKA among various groups. An average onset age of 27.3 years was found in 10 SPTCL cases. Clinically, these patients primarily presented with multiple subcutaneous nodules on the trunk and lower extremities, accompanied by intermittent high fever. One case showed lymph node metastasis, while no other distant organ metastasis being observed in any case. Pathologically, there was an infiltration of a large number of atypical lymphocytes within the fat lobules, characterized as a cytotoxic type. AURKA stanning was positive in 6 out of 10 SPTCL cases, while no positive cases were found in the control groups. 1) SPTCL predominantly affects young individuals and can be identified by nodular erythema on the trunk, intermittent high fever, and infiltration of atypical cytotoxic lymphocytes within fat lobules. 2) For early-stage cases without metastasis, monotherapy with glucocorticoids or immunosuppressants such as cyclosporine can be considered. 3) High expression of AURKA in SPTCL tissues suggests that AURKA could be a potential biomarker for disease diagnosis, providing a theoretical basis for further targeted therapy.

Recent Advances in Immunotherapy and Targeted Therapy of Triple Negative Breast Cancer.

The truancy of representation of the estrogen, progesterone, and human epidermal growth factor receptors occurs during TNBC. TNBC is recognized for the upper reappearance and has a poorer diagnosis compared with rest breast cancer (BC) types. Presently, as such, no targeted therapy is approved for TNBC and treatment options are subjected to chemotherapy and surgery, which have high mortality rates. Hence, the current article focuses on the scenario of TNBC vital pathways and discusses the latest advances in TNBC treatment, including immune checkpoint inhibitors (ICIs), PARP suppressors, and cancer vaccines. Immunotherapy and ICIs, like PD 1 and PD L1 suppressors, displayed potential in clinical trials (CTs). These suppressors obstruct the mechanisms which allow tumor cells to evade the system thereby boosting the body's defense against TNBC. Immunotherapy, either alone or combined with chemotherapy has demonstrated patient outcomes such as increased survival rates and reduced treatment-related side effects. Additionally, targeted therapy approaches include BRCA/2 mutation poly ribose polymerase inhibitors, Vascular Endothelial Growth Factor Receptor (VEGFR) inhibitors, Epidermal growth factor receptor inhibitors, Fibroblast growth factor inhibitors, Androgen Receptor inhibitors, PIK3/AKT/mTOR pathway inhibitors, Cyclin-dependent kinase (CDK) inhibitors, Notch signaling pathway inhibitors, Signal transducer and activator of transcription 3 (STAT3) signaling pathway inhibitors, Chimeric antigen receptor T (CAR-T) cell therapy, Transforming growth factor (TGF) -β inhibitors, Epigenetic modifications (EPM), Aurora Kinase inhibitors and antibody-drug conjugates. We also highlight ongoing clinical trials and potential future directions for TNBC therapy. Despite the challenges in treating TNBC, recent developments in understanding the molecular and immune characteristics of TNBC have opened up new opportunities for targeted therapies, which hold promise for improving outcomes in this aggressive disease.

Profiling Cellular Morphological Changes Induced by Dual-Targeting PROTACs of Aurora Kinase and RNA-Binding Protein YTHDF2.

Proteolysis targeting chimeras (PROTACs) are new chemical modalities that degrade proteins of interest, including established kinase targets and emerging RNA-binding proteins (RBPs). Whereas diverse sets of biochemical, biophysical and cellular assays are available for the evaluation and optimizations of PROTACs in understanding the involved ubiquitin-proteasome-mediated degradation mechanism and the structure-degradation relationship, a phenotypic method profiling the cellular morphological changes is rarely used. In this study, first, we reported the only examples of PROTACs degrading the mRNA-binding protein YTHDF2 via screening of multikinase PROTACs. Second, we reported the profiling of cellular morphological changes of the dual kinase- and RBP-targeting PROTACs using the unbiased cell painting assay (CPA). The CPA analysis revealed the high biosimilarity with the established aurora kinase cluster and annotated aurora kinase inhibitors, which reflected the association between YTHDF2 and the aurora kinase signaling network. Broadly, the results demonstrated that the cell painting assay can be a straightforward and powerful approach to evaluate PROTACs. Complementary to the existing biochemical, biophysical and cellular assays, CPA provided a new perspective in characterizing PROTACs at the cellular morphology.

Drug-induced senescence by aurora kinase inhibitors attenuates innate immune response of macrophages on gastric cancer organoids

Diffuse-type gastric cancer (DGC) is a subtype of gastric cancer with aggressiveness and poor prognosis. It is of great significance to find sensitive drugs for DGC. In the current study, a total of 20 patient-derived organoids (PDOs) were analyzed for screening the therapeutic efficacy of small molecule kinases inhibitors on gastric cancers, especially the therapeutic difference between intestinal-type gastric cancer (IGCs) and DGCs. The IGCs are sensitive to multiple kinases inhibitors, while DGCs are resistant to most of these kinases inhibitors. It was found that DGCs showed drug-induced senescent phenotype after treatment by aurora kinases inhibitors (AURKi) Barasertib-HQPA and Danusertib. The cell diameter of cancer cells are increased with stronger staining of senescence-associated β-galactosidase (SA-β-GAL), and characteristic appearance of multinucleated giant cells. The senescent cancer cells secrete large amounts of chemokine MCP-1/CCL2, which recruit and induce macrophage to M2-type polarization in PDOs of DGC (DPDOs)-macrophage co-culture system. The up-regulation of local MCP-1/CCL2 can interact with MCP-1/CCL2 receptor (CCR2) expressed on macrophages and suppress their innate immunity to cancer cells. Overall, the special response of DGC to AURKi suggests that clinicians should select a sequential therapy with senescent cell clearance after AURKi treatment for DGC.

A novel role of AURKA kinase in erythroblast enucleation.

Generation of mammalian red blood cells requires the expulsion of polarized nuclei late in terminal erythroid differentiation. However, the mechanisms by which spherical erythroblasts determine the direction of nuclear polarization and maintain asymmetry during nuclear expulsion are poorly understood. Given the analogy of erythroblast enucleation to asymmetric cell division and the key role of Aurora kinases in mitosis, we sought to investigate the function of Aurora kinases in erythroblast enucleation. We found that AURKA (Aurora kinase A) is abundantly expressed in orthochromatic erythroblasts. Intriguingly, high-resolution confocal microscopy analyses revealed that AURKA co-localized with the centrosome on the side of the nucleus opposite its membrane contact point during polarization and subsequently translocated to the anterior end of the protrusive nucleus upon nuclear exit. Mechanistically, AURKA regulated centrosome maturation and localization via interaction with i-tubulin to provide polarization orientation for the nucleus. Furthermore, we identified ECT2 (epithelial cell transforming 2), a guanine nucleotide exchange factor, as a new interacting protein and ubiquitination substrate of AURKA. After forming the nuclear protrusion, AURKA translocated to the anterior end of the protrusive nucleus to directly degrade ECT2, which is partly dependent on kinase activity of AURKA. Moreover, knockdown of ECT2 rescued impaired enucleation caused by AURKA inhibition. Our findings have uncovered a previously unrecognized role of Aurora kinases in the establishment of nuclear polarization and eventual nuclear extrusion and provide new mechanistic insights into erythroblast enucleation.

P-349 Impact of an Aurora kinase inhibitor on AML cells and mouse ovarian follicles in vitro

Abstract Study question Can an aurora kinase B/C inhibitor suppress AML cell line proliferation while not impacting on mouse follicles in vitro? Summary answer Exposure to an aurora kinase inhibitor at a predetermined cytotoxic concentration suppressed AML cell proliferation but had no impact on subsequent follicle health in vitro. What is known already There is a risk that cryopreserved ovarian tissue from young women with a leukaemia diagnosis harbours leukemic cells, which on grafting could transfer disease. Novel chemotherapy agents, specifically aurora kinase inhibitors [ e.g. GSK 1070916 (GSK) ], target proteins involved in chromosomal alignment and segregation during mitosis and meiosis. It is anticipated that aurora kinase inhibitors would have an impact on the development of all somatic cells, including granulosa cells proliferating during follicle growth, however a previous study using ovarian tissue pieces indicated no impact on follicles. Study design, size, duration Primary and secondary follicles (diameter ≤ 100 µm) were manually dissected from adult mouse ovaries and embedded in an extracellular scaffold together with >1,000 AML cells. Individual follicles and AML cells were cultured for 7 days followed by exposure to GSK for 24 hours. GSK was removed by washing and the culture continued for another two days at which time cells were assessed for normal morphology and survival with live/dead staining (Calcein AM/ Ethidium Homodimer-1). Participants/materials, setting, methods The leukemic cell line OC1-AML-3 (DSMZ) was cultured in RPMI-1640 +10% FCS and routinely passaged as recommended. Cell proliferation and cytotoxicity were assessed using the Alamar Blue assay. 20% DMSO was used as a positive control in the cytotoxicity assays and live/dead evaluation. Follicles were cultured in αMEM, ITS, FSH, ascorbic acid and 10% FCS under oil in 5%CO2 : 95% air. Survival and growth were evaluated in two extracellular scaffolds; UltiMatrix and Hystem™-HP. Main results and the role of chance Follicle survival and growth was better (p < 0.05) in UltiMatrix (84.7%; 61/72) compared to Hystem™-HP (72.0%;77/107) with an average increase of 20 µm in diameter at day 7. When OCI-AML-3 cells (0.7 x105/ml) were exposed to a range of concentrations of GSK (10nM to 10µM) for 24hr in an in vitro cytotoxicity assessment, survival was reduced to 0% at a concentration of 10µM. The 20% DMSO positive control also resulted in 0% survival. However, in the 3- dimensional scaffold culture, exposure to 10 µM GSK for 24hr resulted in a mean survival of OCI-AML-3 cells of 27% (100 cells counted/ well) which was similar to the 20% DMSO positive control (32%) and significantly different to the negative (no GSK) control (95%; p < 0.01). Follicles exposed to GSK appeared alive, emitting a strong green fluorescence for both oocyte and granulosa cells, although some of the surface follicular cells were dead. Live/dead staining of GSK exposed follicles was similar to follicles not exposed to GSK. In contrast, the majority of the follicular cells were dead following exposure to 20% DMSO. Limitations, reasons for caution Due to whole mount assessment of the follicles for live/dead staining, it is difficult to determine whether the oocyte is alive. In scaffold culture some of the free cells present may be of follicular origin, potentially resulting in overestimation of the proportion of AML cells alive after GSK treatment. Wider implications of the findings This 3- dimensional culture system, incorporating a follicle and a leukemic cell line within a scaffold provides a good model to assess the impact of chemotherapy on both cell types and could be applicable for human follicles. Trial registration number Not applicable

Recent Updates on Oncogenic Signaling of Aurora Kinases in Chemosensitive, Chemoresistant Cancers: Novel Medicinal Chemistry Approaches for Targeting Aurora Kinases.

The Aurora Kinase family (AKI) is composed of serine-threonine protein kinases involved in the modulation of the cell cycle and mitosis. These kinases are required for regulating the adherence of hereditary-related data. Members of this family can be categorized into aurora kinase A (Ark-A), aurora kinase B (Ark-B), and aurora kinase C (Ark-C), consisting of highly conserved threonine protein kinases. These kinases can modulate cell processes such as spindle assembly, checkpoint pathway, and cytokinesis during cell division. The main aim of this review is to explore recent updates on the oncogenic signaling of aurora kinases in chemosensitive/chemoresistant cancers and to explore the various medicinal chemistry approaches to target these kinases. We searched Pubmed, Scopus, NLM, Pubchem, and Relemed to obtain information pertinent to the updated signaling role of aurora kinases and medicinal chemistry approaches and discussed the recently updated roles of each aurora kinases and their downstream signaling cascades in the progression of several chemosensitive/chemoresistant cancers; subsequently, we discussed the natural products (scoulerine, Corynoline, Hesperidin Jadomycin-B, fisetin), and synthetic, medicinal chemistry molecules as aurora kinase inhibitors (AKIs). Several natural products' efficacy was explained as AKIs in chemosensitization and chemoresistant cancers. For instance, novel triazole molecules have been used against gastric cancer, whereas cyanopyridines are used against colorectal cancer and trifluoroacetate derivatives could be used for esophageal cancer. Furthermore, quinolone hydrazine derivatives can be used to target breast cancer and cervical cancer. In contrast, the indole derivatives can be preferred to target oral cancer whereas thiosemicarbazone-indole could be used against prostate cancer, as reported in an earlier investigation against cancerous cells. Moreover, these chemical derivatives can be examined as AKIs through preclinical studies. In addition, the synthesis of novel AKIs through these medicinal chemistry substrates in the laboratory using in silico and synthetic routes could be beneficial to develop prospective novel AKIs to target chemoresistant cancers. This study is beneficial to oncologists, chemists, and medicinal chemists to explore novel chemical moiety synthesis to target specifically the peptide sequences of aurora kinases in several chemoresistant cancer cell types.

ATRT-18. ALISERTIB USED IN PEDIATRIC ATRT

Abstract BACKGROUND Atypical rhabdoid tumor (ATRT) is a rare and aggressive primary CNS tumor caused by variants or deletions in the tumor suppressor gene SMARCB1 (aka INI 1). SMARCB1 targets Aurora A kinase (AURKA), an important oncoprotein of the cell cycle. AURKA dysregulation can lead to genomic instability through its oncogenic effects. Alisertib is a selective AURKA inhibitor that has been explored for treatment in various cancers, including pediatric malignancies. METHODS Retrospective chart review of five patients diagnosed with ATRT, treated with Alisertib, at Nicklaus Children’s Hospital from 2019 - 2024. RESULTS of the 5 patients; three were females and two males, with a median age at diagnosis of 2 years. Only one patient had a germline mutation while the rest had somatic mutations. Prior to starting Alisertib therapy, all five patients received chemotherapy per multiple protocols; four patients underwent focal radiation therapy, three patients underwent resection, and two patients underwent tandem autologous transplants. All five patients were treated solely with Alisertib, median dose of 60 mg/m2 PO daily. Two patients had reduced doses during therapy secondary to cytopenia. One patient completed therapy over 13 months with partial response based on imaging. One patient presented progression of disease while on therapy and for that reason treatment was stopped. Three patients continue treatment: two with only Alisertib, one using Avastin and Sirolimus concurrently. CONCLUSIONS Prognosis in patients with ATRT is usually poor given its aggressive nature and high rate of recurrence despite intervention. It is important to note that treatment of ATRT is highly individualized and typically involves a combination of therapeutic modalities. While Alisertib is one of the newest treatment options, there’s limited literature of clinical improvement in patients with ATRT using this treatment. Therefore, further research on novel treatment options is warranted for the future.

Aurora Kinase A inhibition enhances DNA damage and tumor cell death with 131I-MIBG therapy in high-risk neuroblastoma

BackgroundNeuroblastoma is the most common extra-cranial pediatric solid tumor. 131I-metaiodobenzylguanidine (MIBG) is a targeted radiopharmaceutical highly specific for neuroblastoma tumors, providing potent radiotherapy to widely metastatic disease. Aurora kinase A (AURKA) plays a role in mitosis and stabilization of the MYCN protein in neuroblastoma. We aimed to study the impact of AURKA inhibitors on DNA damage and tumor cell death in combination with 131I-MIBG therapy in a pre-clinical model of high-risk neuroblastoma.ResultsUsing an in vivo model of high-risk neuroblastoma, we demonstrated a marked combinatorial effect of 131I-MIBG and alisertib on tumor growth. In MYCN amplified cell lines, the combination of radiation and an AURKA A inhibitor increased DNA damage and apoptosis and decreased MYCN protein levels.ConclusionThe combination of AURKA inhibition with 131I-MIBG treatment is active in resistant neuroblastoma models.

Pharmacological inhibition of protein kinase D2/Aurora kinase A signalling axis suppresses G2/M cell cycle progression and proliferation of epithelial ovarian cancer cells

Epithelial ovarian cancer (EOC) is the deadliest gynecological malignancy with poor prognosis and patient survival outcome. Protein kinase D2 (PKD2) belongs to Ca++/calmodulin-dependent serine/threonine kinase family and its aberrant expression is associated with many cellular and physiological functions associated with tumorigenesis including cell proliferation. We show that PKD2 is activated during G2/M cell cycle transition and its catalytic inactivation by small molecule inhibitor CRT0066101 or genetic knockdown caused suppression of EOC cell proliferation followed by a delay into mitotic entry. Our RNASeq analysis of PKD2-inactivated EOC cells revealed significant downregulation of genes associated with cell cycle including Aurora kinase A, a critical mitotic regulator. Mechanistically, PKD2 positively regulated Aurora kinase A stability at both transcriptional and post-translational levels by interfering with the function of Fbxw7, drove G2/M cell cycle transition and EOC cell proliferation. Moreover, pharmacological inhibition of Aurora kinase A by small molecule CD532 or its shRNA-mediated genetic knockdown suppressed EOC cell proliferation, induced G2/M cell cycle arrest and mitotic catastrophe followed by apoptosis. Taken together, our results indicated that PKD2 positively regulates Aurora kinase A during G2/M cell cycle entry and pharmacological targeting of PKD2/Aurora kinase A signalling axis could serve as a novel therapeutic intervention against a lethal pathology like EOC.