Perifosine, an Oral Bioactive Novel Akt Inhibitor, Induces In Vitro and In Vivo Antitumor Activity in Waldenstrom Macroglobulinemia.

Abstract Background: Waldenstrom’s Macroglobulinemia (WM) is a low-grade lymphoplasmacytic lymphoma with limited options of therapy. The PI3k/Akt pathway is a critical regulator of cell survival. Our previous studies using proteomic analysis have demonstrated upregulation of members of the PI3k/Akt pathway in WM. We examined whether the new Akt inhibitor perifosine (NSC 639966; Keryx, NY) induces cytotoxicity in WM. Methods: WM cell lines (BCWM1 and WSU-WM) and IgM secreting low-grade lymphoma cell lines (MEC1, RL) were used. Primary CD19+ malignant cells were obtained from patients after informed consent. Inhibition of proliferation was measured using the MTT assay; DNA synthesis was measured using the thymidine uptake assay and apoptosis using Apo2.7 flow cytometry. Bone marrow stromal cells (BMSC) confer growth and resistance to conventional treatments. We therefore, tested the effect of perifosine on WM cells co-cultured with BMSC. Immunoblotting for signaling pathways was performed at different time (30 minutes to 16 hrs) and doses of therapy. In vivo activity of perifosine was assessed using a SCID-irradiated model with subcutaneous tumors in which perifosine was administered by oral gavage daily (35 mg/kg/day). A two-sided t-test was used to determine statistical differences. Results: Perifosine inhibited phosphorylation of Akt in a dose- and time- dependent fashion, as well as downstream GSK3a/b and ribosomal phospho-S6. Perifosine inhibited Akt activity as confirmed by Akt kinase assay. Perifosine induced significant cytotoxicity and inhibition of DNA synthesis with an IC50 of 5-20uM in all cell lines tested. Similar effects were observed in primary CD19+ patient WM cells. Perifosine induced apoptosis in WM cells as demonstrated by flow cytometry. The mechanism of apoptosis induced by perifosine was through activation of SAPK/JNK pathway, followed by caspase-8, -9 and PARP cleavage. The JNK inhibitor SP600125 abrogated perifosine-induced apoptosis. The growth inhibitory effects of perifosine were significant even in the presence of BMSC, IL-6 and IGF-1, which induce resistance to conventional therapies. Importantly, perifosine did not induce cytotoxicity in healthy donor peripheral blood mononuclear cells or in hematopietic stem cells in a methylcellulose colony forming cell assay, indicating lack of toxicity on normal cells. Interestingly, MAPK members such as MEK/ERK were activated by perifosine. The MEK inhibitor U0126 significantly enhanced perifosine-induced cytotoxicity in WM cells, indicating that this combination may be synergistic in vivo. Finally, perifosine induced significant reduction in WM tumor growth in vivo, as compared to control cohort treated with vehicle only at week 6 (p=0.05). Conclusion: Perifosine has significant antitumor activity in WM both in vitro and in vivo. These results provide the framework for clinical evaluation of perifosine in WM. Supported in part by the Leukemia and Lymphoma Society, the Lymphoma Research Foundation and an American Society of Hematology Scholar Award. * XL and XJ are co-first authors.

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Primary Waldesntrom Macroglobulinemia Cells Harbor Constitutive Activation of Akt, mTOR, Rictor and Raptor: Rational for Testing a Dual Inhibitor of the PI3K/Akt and mTOR Pathways in This Disease.

Blood ◽

10.1182/blood.v114.22.3843.3843 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3843-3843

Author(s):

Aldo M. Roccaro ◽

Antonio Sacco ◽

Emanuel N. Husu ◽

Costas M Pitsillides ◽

Steven Vesole ◽

...

Keyword(s):

Bone Marrow ◽

Flow Cytometry ◽

Dna Synthesis ◽

Cell Lines ◽

Thymidine Uptake ◽

Low Grade ◽

Dependent Manner ◽

Dual Inhibitor

Abstract Abstract 3843 Poster Board III-779 Background The PI3K/Akt and mTOR pathways play a pivotal role in the initiation and progression of malignancies, enhancing cell survival by stimulating cell proliferation and inhibiting apoptosis. Therefore, it is critical to examine therapeutic agents that explicitly target this pathway, specifically in tumors that harbor activation of the PI3K/Akt pathway, such as Waldenstrom macroglobulinemia (WM). Methods Primary-CD19+ bone marrow-derived WM cells, -bone marrow stromal cells, WM and IgM secreting low-grade lymphoma cell lines (BCWM.1, MEC1, RL), and primary normal CD19+ peripheral blood-derived (CD19+ PB)cells were used. Gene-expression and microRNA profiling have been performed on primary WM cells, as compared to CD19+ PB cells. Cytotoxicity, DNA synthesis, cell cycle and apoptosis were measured by thymidine uptake, MTT, PI staining, and Apo2.7/flow cytometry analysis, respectively. Cell signaling and apoptotic pathways were delineated by Western Blot and immunofluorescence analysis. In vivo homing has been assessed by in vivo flow cytometry. Results Primary bone-marrow derived WM cells are characterized by lower expression of PTEN gene and protein; higher expression of pospho(p)-Akt, p-mTOR, rictor and raptor, as compared to their normal cellular counterpart (CD19+ PB cells). We also observed that microRNA-542-3p and -494 are more highly expressed in primary WM cells as compared to normal CD19+ PB cells (P<.01); and they both target PTEN, as predicted using TargetScan, PicTar, and miRanda algorithms, suggesting their role in inhibiting PTEN expression. We next assessed the effect of the dual PI3K/Akt and mTOR inhibitor NVP-BEZ235 (Novartis, Basel, Switzerland). This agent induced cytotoxicity and inhibited DNA synthesis (IC50 20-25nM) in BCWM.1 at 48 hours. Similar effects were demonstrated in all IgM secreting cell lines and in primary CD19+ WM cells (IC50 20-50nM). No cytotoxicity was observed on CD19+ PB cells, indicating selective toxicity of the compound on the malignant lymphoplasmacytic clone. NVP-BEZ235 inhibited p-Akt and p-mTOR, as well as the downstream Akt- targeted proteins GSK3a/b, p-S6R and p-p70S6, in a dose-dependent manner. Akt and mTOR in vitro kinase activity was also inhibited by NVP-BEZ235 treatment. In addition, NVP-BEZ235 inhibited both rictor and raptor, thus abrogating the rictor-induced Akt phosphorylation in WM cells. NVP-BEZ235 also induced significant cytotoxicity in WM cells in a caspase-dependent and -independent manner, through targeting the forkhead box transcription factors. Finally, NVP-BEZ235 targeted WM cells in the context of bone marrow microenvironment evidenced by significant inhibition of migration, adhesion in vitro and homing in vivo. Conclusion These studies therefore show that dual targeting of the PI3K/mTOR pathway represents a promising therapy for tumors that harbor activation of the PI3K/mTOR signaling cascade such as WM. Disclosures: Ghobrial: Millennium : Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau.

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The PI3K/Akt Pathway Is an Important Regulator of Homing and Adhesion in Waldenstrom’s Macroglobulinemia.

Blood ◽

10.1182/blood.v108.11.2417.2417 ◽

2006 ◽

Vol 108 (11) ◽

pp. 2417-2417 ◽

Cited By ~ 2

Author(s):

Xavier Leleu ◽

Hai Ngo ◽

Judy Runnels ◽

Costas Pitsillides ◽

Joel Spencer ◽

...

Keyword(s):

Flow Cytometry ◽

Confocal Microscopy ◽

Treated Mouse ◽

Akt Pathway ◽

Low Grade ◽

Dependent Manner ◽

Surface Adhesion ◽

Number Of Cells

Abstract Background: Waldenstrom Macroglobulinemia (WM) is a low-grade lymphoma characterized by widespread involvement of the bone marrow (BM) and involvement of lymph nodes and hepatosplenomegaly (HSM) in about 20% of the patients. We have recently demonstrated that the presence of HSM is one of the most important adverse prognostic factors in WM. The mechanisms of trafficking of WM cells to and from the BM and lymphoid organs is not well defined. The PI3k/Akt pathway is constitutively activated in WM, and regulates migration/homing in cancer cells and B-cells. We hypothesized that the Akt inhibitor perifosine (NSC 639966; Keryx Biopharmaceuticals, NY) modulates homing of WM cells to the BM. Methods: WM cell line (BCWM.1) was treated with perifosine 2 to 5uM for 2 hours. Surface adhesion receptors were studied using flow cytometry. The adhesion assay coated with fibronectin, a ligand of VLA-4 (EMD Biosciences, CA) was used to test in vitro adhesion. Migration was determined using the transwell migration assay (Costar, NY). We then studied homing of WM into the BM niches using in vivo flow cytometry and confocal microscopy in Balb/c mice. In brief, BCWM.1 were incubated with 5uM perifosine for 2 hrs (or control PBS). The cells were fluorescently labeled by incubation with the dialkylcarbocyanine membrane dye, “DiD” (Molecular Probes), 0.5uM dye for 30 minutes. Cells were then injected in the tail vein of the Balb/c mice, and in vivo confocal flow cytometry was performed on an artery from the ear lobe of the mice. Cell counts were obtained every 5 min. from the time of injection. In vivo confocal microscopy and two-photon microscopy was performed to study cells homing to BM vasculature of the skull (BM niches). Results: WM cells expressed very high levels of VLA-4, with a median 95% expression. BCWM.1 demonstrated increased adhesion to fibronectin-coated wells as compared to BSA-coated wells. Perifosine inhibited adhesion in a dose dependent manner with 50% decrease in adhesion at 2uM. Perifosine 10uM did not change the level of surface expression of VLA-4 after 6 and 24 hrs, indicating an effect on intracellular signaling but not on surface adhesion molecules. Perifosine 5uM significantly inhibited migration of BCWM.1 in response to SDF-1, a ligand that induces migration of WM cells. Perifosine also demonstrated significant inhibition of in vivo homing of WM cells to the BM niches. The number of cells in the peripheral circulation decreased dramatically (75% decrease) after 1 hr in the control, indicating homing, whereas there was a 40% reduction in the cells at 1hr after perifosine treatment (p=0.001). We then looked at the images obtained from the BM niches. The number of cells that homed and adhered to these areas was lower in the perifosine-treated mouse compared to the control mouse, indicating that fewer cells homed to the BM of the treated mouse. Conclusion: These results confirm that the PI3K/Akt pathway is important for migration, adhesion and homing of WM in vitro and in vivo.

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Design, Synthesis, Molecular Modeling and Antitumor Evaluation of Novel Indolyl-Pyrimidine Derivatives with EGFR Inhibitory Activity

Molecules ◽

10.3390/molecules26071838 ◽

2021 ◽

Vol 26 (7) ◽

pp. 1838

Author(s):

Naglaa M. Ahmed ◽

Mahmoud M. Youns ◽

Moustafa K. Soltan ◽

Ahmed M. Said

Keyword(s):

Molecular Modeling ◽

Antitumor Activity ◽

Cell Lines ◽

Cancer Cell ◽

Antiproliferative Activity ◽

Antitumor Agents ◽

Cancer Cell Lines ◽

Normal Cells

Scaffolds hybridization is a well-known drug design strategy for antitumor agents. Herein, series of novel indolyl-pyrimidine hybrids were synthesized and evaluated in vitro and in vivo for their antitumor activity. The in vitro antiproliferative activity of all compounds was obtained against MCF-7, HepG2, and HCT-116 cancer cell lines, as well as against WI38 normal cells using the resazurin assay. Compounds 1–4 showed broad spectrum cytotoxic activity against all these cancer cell lines compared to normal cells. Compound 4g showed potent antiproliferative activity against these cell lines (IC50 = 5.1, 5.02, and 6.6 μM, respectively) comparable to the standard treatment (5-FU and erlotinib). In addition, the most promising group of compounds was further evaluated for their in vivo antitumor efficacy against EAC tumor bearing mice. Notably, compound 4g showed the most potent in vivo antitumor activity. The most active compounds were evaluated for their EGFR inhibitory (range 53–79 %) activity. Compound 4g was found to be the most active compound against EGFR (IC50 = 0.25 µM) showing equipotency as the reference treatment (erlotinib). Molecular modeling study was performed on compound 4g revealed a proper binding of this compound inside the EGFR active site comparable to erlotinib. The data suggest that compound 4g could be used as a potential anticancer agent.

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γδ T cells for immune therapy of patients with lymphoid malignancies

Blood ◽

10.1182/blood-2002-12-3665 ◽

2003 ◽

Vol 102 (1) ◽

pp. 200-206 ◽

Cited By ~ 362

Author(s):

Martin Wilhelm ◽

Volker Kunzmann ◽

Susanne Eckstein ◽

Peter Reimer ◽

Florian Weissinger ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Antitumor Activity ◽

Low Dose ◽

Γδ T Cells ◽

Low Grade ◽

Treatment Schedule ◽

Γδ T Cell

Abstract There is increasing evidence that γδ T cells have potent innate antitumor activity. We described previously that synthetic aminobisphosphonates are potent γδ T cell stimulatory compounds that induce cytokine secretion (ie, interferon γ [IFN-γ]) and cell-mediated cytotoxicity against lymphoma and myeloma cell lines in vitro. To evaluate the antitumor activity of γδ T cells in vivo, we initiated a pilot study of low-dose interleukin 2 (IL-2) in combination with pamidronate in 19 patients with relapsed/refractory low-grade non-Hodgkin lymphoma (NHL) or multiple myeloma (MM). The objectives of this trial were to determine toxicity, the most effective dose for in vivo activation/proliferation of γδ T cells, and antilymphoma efficacy of the combination of pamidronate and IL-2. The first 10 patients (cohort A) who entered the study received 90 mg pamidronate intravenously on day 1 followed by increasing dose levels of continuous 24-hour intravenous (IV) infusions of IL-2 (0.25 to 3 × 106 IU/m2) from day 3 to day 8. Even at the highest IL-2 dose level in vivo, γδ T-cell activation/proliferation and response to treatment were disappointing with only 1 patient achieving stable disease. Therefore, the next 9 patients were selected by positive in vitro proliferation of γδ T cells in response to pamidronate/IL-2 and received a modified treatment schedule (6-hour bolus IV IL-2 infusions from day 1-6). In this patient group (cohort B), significant in vivo activation/proliferation of γδ T cells was observed in 5 patients (55%), and objective responses (PR) were achieved in 3 patients (33%). Only patients with significant in vivo proliferation of γδ T cells responded to treatment, indicating that γδ T cells might contribute to this antilymphoma effect. Overall, administration of pamidronate and low-dose IL-2 was well tolerated. In conclusion, this clinical trial demonstrates, for the first time, that γδ T-cell–mediated immunotherapy is feasible and can induce objective tumor responses. (Blood. 2003;102:200-206)

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Identification of Prostaglandin F2 Receptor Negative Regulator (PTGFRN) as an internalizable target in cancer cells for antibody-drug conjugate development

PLoS ONE ◽

10.1371/journal.pone.0246197 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0246197

Author(s):

Jorge Marquez ◽

Jianping Dong ◽

Chun Dong ◽

Changsheng Tian ◽

Ginette Serrero

Keyword(s):

Flow Cytometry ◽

Western Blot ◽

Cell Lines ◽

Cancer Cell ◽

Cancer Cell Lines ◽

Negative Regulator ◽

Target Validation ◽

Antibody Drug

Antibody-drug conjugates (ADC) are effective antibody-based therapeutics for hematopoietic and lymphoid tumors. However, there is need to identify new targets for ADCs, particularly for solid tumors and cancers with unmet needs. From a hybridoma library developed against cancer cells, we selected the mouse monoclonal antibody 33B7, which was able to bind to, and internalize, cancer cell lines. This antibody was used for identification of the target by immunoprecipitation and mass spectrometric analysis, followed by target validation. After target validation, 33B7 binding and target positivity were tested by flow cytometry and western blot analysis in several cancer cell lines. The ability of 33B7 conjugated to saporin to inhibit in vitro proliferation of PTFRN positive cell lines was investigated, as well as the 33B7 ADC in vivo effect on tumor growth in athymic mice. All flow cytometry and in vitro internalization assays were analyzed for statistical significance using a Welsh’s T-test. Animal studies were analyzed using Two-Way Analysis of Variance (ANOVA) utilizing post-hoc Bonferroni analysis, and/or Mixed Effects analysis. The 33B7 cell surface target was identified as Prostaglandin F2 Receptor Negative Regulator (PTGFRN), a transmembrane protein in the Tetraspanin family. This target was confirmed by showing that PTGFRN-expressing cells bound and internalized 33B7, compared to PTGFRN negative cells. Cells able to bind 33B7 were PTGFRN-positive by Western blot analysis. In vitro treatment PTGFRN-positive cancer cell lines with the 33B7-saporin ADC inhibited their proliferation in a dose-dependent fashion. 33B7 conjugated to saporin was also able to block tumor growth in vivo in mouse xenografts when compared to a control ADC. These findings show that screening antibody libraries for internalizing antibodies in cancer cell lines is a good approach to identify new cancer targets for ADC development. These results suggest PTGFRN is a possible therapeutic target via antibody-based approach for certain cancers.

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„IN VITRO“ AND „IN VIVO“ ANTITUMOR ACTIVITY OF PLATINUM(II) COMPLEXES WITH MALONIC ACID ON BREAST AND COLORECTAL CARCINOMA CELL LINES

10.46793/iccbi21.293f ◽

2021 ◽

Author(s):

Andjela Franich ◽

◽

Milica Dimitrijević Stojanović ◽

Snežana Rajković ◽

Marina Jovanović ◽

...

Keyword(s):

Antitumor Activity ◽

Colorectal Carcinoma ◽

Cell Lines ◽

Tumor Model ◽

Carcinoma Cells ◽

Spectroscopic Techniques ◽

Murine Cell Line ◽

In Vivo Antitumor Activity

Four Pt(II) complexes of the general formula [Pt(L)(5,6-epoxy-1,10-phen)], where L is anion of malonic (mal, Pt1), 2-methylmalonic (Me-mal, Pt2), 2,2-dimethylmalonic (Me2-mal, Pt3) or 1,1- cyclobutanedicarboxylic (CBDCA, Pt4) acid while 5,6-epoxy-1,10-phen is bidentately coordinated 5,6-epoxy-5,6-dihydro-1,10-phenanthroline were synthesized and characterized by elemental microanalysis, IR, UV-Vis and NMR (1H and 13C) spectroscopic techniques. In vitro anticancer activity of novel platinum(II) complexes have been investigated on human and murine cancer cell lines, as well as normal murine cell line by MTT assay. The obtained results indicate that studied platinum(II) complexes exhibited strong cytotoxic activity against murine breast carcinoma cells (4T1), human (HCT116) and murine (CT26) colorectal carcinoma cells. Complex Pt3 display stronger selectivity toward carcinoma cells in comparison to other tested platinum(II) complexes exhibiting beneficial antitumor activity mainly via the induction of apoptosis, as well as inhibition of cell proliferation and migration. Further study showed that Pt3 complex also carry significant in vivo antitumor activity in orthotopical 4T1 tumor model without detected liver, kidney, lung, and heart toxicity. All results imply that these novel platinum(II) complexes have a good anti-tumor effect on breast and colorectal cancer in vivo and in vitro and the affinity to become possible candidates for treatment in anticancer therapy.

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Targeted Brain Tumor Therapy by Inhibiting the MDM2 Oncogene: In Vitro and In Vivo Antitumor Activity and Mechanism of Action

Cells ◽

10.3390/cells9071592 ◽

2020 ◽

Vol 9 (7) ◽

pp. 1592

Author(s):

Surendra R. Punganuru ◽

Viswanath Arutla ◽

Wei Zhao ◽

Mehrdad Rajaei ◽

Hemantkumar Deokar ◽

...

Keyword(s):

Brain Tumor ◽

Antitumor Activity ◽

Cell Lines ◽

Tumor Therapy ◽

Single Agent ◽

M Cell ◽

In Vivo Antitumor Activity ◽

The Brain

There is a desperate need for novel and efficacious chemotherapeutic strategies for human brain cancers. There are abundant molecular alterations along the p53 and MDM2 pathways in human glioma, which play critical roles in drug resistance. The present study was designed to evaluate the in vitro and in vivo antitumor activity of a novel brain-penetrating small molecule MDM2 degrader, termed SP-141. In a panel of nine human glioblastoma and medulloblastoma cell lines, SP-141, as a single agent, potently killed the brain tumor-derived cell lines with IC50 values ranging from 35.8 to 688.8 nM. Treatment with SP-141 resulted in diminished MDM2 and increased p53 and p21cip1 levels, G2/M cell cycle arrest, and marked apoptosis. In intracranial xenograft models of U87MG glioblastoma (wt p53) and DAOY medulloblastoma (mutant p53) expressing luciferase, treatment with SP-141 caused a significant 4- to 9-fold decrease in tumor growth in the absence of discernible toxicity. Further, combination treatment with a low dose of SP-141 (IC20) and temozolomide, a standard anti-glioma drug, led to synergistic cell killing (1.3- to 31-fold) in glioma cell lines, suggesting a novel means for overcoming temozolomide resistance. Considering that SP-141 can be taken up by the brain without the need for any special delivery, our results suggest that SP-141 should be further explored for the treatment of tumors of the central nervous system, regardless of the p53 status of the tumor.

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Cytotoxic, Antitumor and Toxicological Profile of Passiflora alata Leaf Extract

Molecules ◽

10.3390/molecules25204814 ◽

2020 ◽

Vol 25 (20) ◽

pp. 4814

Author(s):

Ricardo G. Amaral ◽

Silvana V. F. Gomes ◽

Luciana N. Andrade ◽

Sara A. dos Santos ◽

Patrícia Severino ◽

...

Keyword(s):

Antitumor Activity ◽

Cell Lines ◽

Leaf Extract ◽

Flowering Plant ◽

White Pulp ◽

Reduced Body ◽

Cell Proliferation Inhibition ◽

S180 Cell

Passiflora alata or passion fruit is a native flowering plant from Amazon, geographically spread from Peru to Brazil. The plant has long been used in folks medicine for its pharmacological properties and is included in the Brazilian Pharmacopoeia since 1929. The aim of this study was to evaluate the potential cytotoxic and antitumor activities of Passiflora alata leaf extract (PaLE) in S180-tumor bearing mice. The percentage of cell proliferation inhibition (% CPI) and IC50 in relation to 4 tumor cell lines were determined in PC3, K-562, HepG2 and S180 cell lines using the MTT assay. PaLE showed a CPI > 75% and greater potency (IC50 < 30 µg/mL) against PC3 and S180 cell lines. PaLE showed antitumor activity in treatments intraperitoneally (36.75% and 44.99% at doses of 100 and 150 mg/kg/day, respectively). Toxicological changes were shown in the reduced body mass associated with reduced food consumption, increased spleen mass associated with histopathological increase in the white pulp of the spleen and increased number of total leukocytes with changes in the percentage relationship between lymphocytes and neutrophils. Our outcomes corroborate the conclusion that PaLE has antitumor activity in vitro and in vivo with low toxicity.

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In Vitro and in Vivo Antitumor Activity of Scutebarbatine A on Human Lung Carcinoma A549 Cell Lines

Molecules ◽

10.3390/molecules19078740 ◽

2014 ◽

Vol 19 (7) ◽

pp. 8740-8751 ◽

Cited By ~ 23

Author(s):

Xiao-Kun Yang ◽

Ming-Yuan Xu ◽

Gui-Sen Xu ◽

Yu-Lan Zhang ◽

Zhao-Xia Xu

Keyword(s):

Antitumor Activity ◽

Cell Lines ◽

Lung Carcinoma ◽

A549 Cell ◽

Human Lung ◽

In Vivo Antitumor Activity ◽

Human Lung Carcinoma

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Aurora-a confers radioresistance in human hepatocellular carcinoma by activating NF-κB signaling pathway

BMC Cancer ◽

10.1186/s12885-019-6312-y ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 3

Author(s):

Ze-Tian Shen ◽

Ying Chen ◽

Gui-Chun Huang ◽

Xi-Xu Zhu ◽

Rui Wang ◽

...

Keyword(s):

Flow Cytometry ◽

Western Blot ◽

Luciferase Reporter ◽

Aurora A ◽

Western Blot Assay ◽

Induced Apoptosis ◽

Mtt Assays ◽

Hcc Cells

Abstract Background Radiotherapy failure is a significant clinical challenge due to the development of resistance in the course of treatment. Therefore, it is necessary to further study the radiation resistance mechanism of HCC. In our early study, we have showed that the expression of Aurora-A mRNA was upregulated in HCC tissue samples or cells, and Aurora-A promoted the malignant phenotype of HCC cells. However, the effect of Aurora-A on the development of HCC radioresistance is not well known. Methods In this study, colony formation assay, MTT assays, flow cytometry assays, RT-PCR assays, Western blot, and tumor xenografts experiments were used to identify Aurora-A promotes the radioresistance of HCC cells by decreasing IR-induced apoptosis in vitro and in vivo. Dual-luciferase reporter assay, MTT assays, flow cytometry assays, and Western blot assay were performed to show the interactions of Aurora-A and NF-κB. Results We established radioresistance HCC cell lines (HepG2-R) and found that Aurora-A was significantly upregulated in those radioresistant HCC cells in comparison with their parental HCC cells. Knockdown of Aurora-A increased radiosensitivity of radioresistant HCC cells both in vivo and in vitro by enhancing irradiation-induced apoptosis, while upregulation of Aurora-A decreased radiosensitivity by reducing irradiation-induced apoptosis of parental cells. In addition, we have showed that Aurora-A could promote the expression of nuclear IkappaB-alpha (IκBα) protein while enhancing the activity of NF-kappaB (κB), thereby promoted expression of NF-κB pathway downstream effectors, including proteins (Mcl-1, Bcl-2, PARP, and caspase-3), all of which are associated with apoptosis. Conclusions Aurora-A reduces radiotherapy-induced apoptosis by activating NF-κB signaling, thereby contributing to HCC radioresistance. Our results provided the first evidence that Aurora-A was essential for radioresistance in HCC and targeting this molecular would be a potential strategy for radiosensitization in HCC.

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