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Poor pancreatic cancer (PC) prognosis has been attributed to its resistance to apoptosis and propensity for early systemic dissemination. Existing therapeutic strategies are often circumvented by the molecular crosstalk between cell-signalling pathways. p53 is mutated in more than 50% of PC and NFκB is constitutively activated in therapy-resistant residual disease; these mutations and activations account for the avoidance of cell death and metastasis. Recently, we demonstrated the anti-PC potential of fucoidan extract from marine brown alga, Turbinaria conoides (J. Agardh) Kützing (Sargassaceae). In this study, we aimed to characterize the active fractions of fucoidan extract to identify their select anti-PC efficacy, and to define the mechanism(s) involved. Five fractions of fucoidan isolated by ion exchange chromatography were tested for their potential in genetically diverse human PC cell lines. All fractions exerted significant dose-dependent and time-dependent regulation of cell survival. Fucoidans induced apoptosis, activated caspase -3, -8 and -9, and cleaved Poly ADP ribose polymerase (PARP). Pathway-specific transcriptional analysis recognized inhibition of 57 and 38 nuclear factor κB (NFκB) pathway molecules with fucoidan-F5 in MiaPaCa-2 and Panc-1 cells, respectively. In addition, fucoidan-F5 inhibited both the constitutive and Tumor necrosis factor-α (TNFα)-mediated NFκB DNA-binding activity in PC cells. Upregulation of cytoplasmic IκB levels and significant reduction of NFκB-dependent luciferase activity further substantiate the inhibitory potential of seaweed fucoidans on NFκB. Moreover, fucoidan(s) treatment increased cellular p53 in PC cells and reverted NFκB forced-expression-related p53 reduction. The results suggest that fucoidan regulates PC progression and that fucoidans may target p53-NFκB crosstalk and dictate apoptosis in PC cells., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Understanding the underlying mechanism by which cancer cells acquire resistance to radiation and favorably selected for its clonal expansion will provide molecular insight into tumor recurrence at the treatment site. In the present study, we investigated the molecular mechanisms prompted in MCF-7 breast cancer cells in response to clinical radiation and the associated coordination of intra- and inter-cellular signaling that orchestrate radio-resistance and tumor relapse/recurrence. Our findings showed that 2 or 10Gy of 137 Cs γ-rays at a dose rate of 1.03Gy/min trigger the activation of nuclear factor kappa B (NF-κB), its DNA-binding activity and recycles its own transcription. NF-κB DNA-binding kinetic analysis demonstrated both sustained and dual phase NF-κB activation with radiation. Gene manipulation approach revealed that radiation triggered NF-κB-mediated TNF-α transcriptional activity. TNF-α blocking approach confirmed that the de novo synthesis and secretion of TNF-α serves as a pre-requisite for the second phase of NF-κB activation and sustained maintenance. Radiation-associated NF-κB-dependent secretion of TNF-α from irradiated cells, in parallel, activates NF-κB in the non-targeted un-irradiated bystander cells. Together, these findings demonstrated that radiation-triggered NF-κB-dependent TNFα secretion is critical for self-sustenance of NF-κB (through autocrine positive feedback signaling) and for coordinating bystander response (through inter-cellular paracrine mechanism) after radiation exposure. Further, the data suggest that this self-sustained NF-κB in the irradiated cells determines radio-resistance, survival advantage and clonal expansion of the tumor cells at the treatment site. Parallel maintenance of NF-ΚB-TNF-α-NF-κB feedback-cycle in the un-irradiated non-targeted bystander cells initiates supportive mechanism for the promotion and progression of surviving tumor cells. Intervening this molecular pathway would help us to achieve disease-free cancer survivors., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: Radiation resistance induced in cancer cells that survive after radiation therapy (RT) could be associated with increased radiation protection, limiting the therapeutic benefit of radiation. Herein we investigated the sequential mechanistic molecular orchestration involved in radiation-induced radiation protection in tumor cells., Results: Radiation, both in the low-dose irradiation (LDIR) range (10, 50, or 100 cGy) or at a higher, challenge dose IR (CDIR), 4 Gy, induced dose-dependent and sustained NFκB-DNA binding activity. However, a robust and consistent increase was seen in CDIR-induced NFκB activity, decreased DNA fragmentation, apoptosis, and cytotoxicity and attenuation of CDIR-inhibited clonal expansion when the cells were primed with LDIR prior to challenge dose. Furthermore, NFκB manipulation studies with small interfering RNA (siRNA) silencing or p50/p65 overexpression unveiled the influence of LDIR-activated NFκB in regulating CDIR-induced DNA fragmentation and apoptosis. LDIR significantly increased the transactivation/translation of the radiation-responsive factors tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), cMYC, and SOD2. Coculture experiments exhibit LDIR-influenced radiation protection and increases in cellular expression, secretion, and activation of radiation-responsive molecules in bystander cells. Individual gene-silencing approach with siRNAs coupled with coculture studies showed the influence of LDIR-modulated TNF-α, IL-1α, cMYC, and SOD2 in induced radiation protection in bystander cells. NFκB inhibition/overexpression studies coupled with coculture experiments demonstrated that TNF-α, IL-1α, cMYC, and SOD2 are selectively regulated by LDIR-induced NFκB., Conclusions: Together, these data strongly suggest that scattered LDIR-induced NFκB-dependent TNF-α, IL-1α, cMYC, and SOD2 mediate radiation protection to the subsequent challenge dose in tumor cells., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Ascertaining the ionizing radiation (IR)-induced bystander response and its preceding molecular regulation would increase our understanding of the mechanism of acute and delayed radiobiological effects. Recent evidence clearly prompted that radiation-induced nuclear factor kappa B (NF-κB) would play a key role in bystander responses in nontargeted cells. Accordingly, we investigated the orchestration of NF-κB signaling after IR in a nontargeted distant organ. Heart tissues from C57/BL6 mice either mock irradiated or exposed (limited to lower abdomen 1 cm diameter) to single-dose IR (SDR: 2 or 10 Gy) or fractionated IR (FIR, 2 Gy per day for 5 days) were examined for onset of abscopal NF-κB signal transduction, translated activity, downstream functional signaling and associated DNA damage. Radiation significantly induced NF-κB DNA binding activity in nontargeted heart. Transcriptional profiling showed that 51, 46 and 26 of 88 genes were significantly upregulated after 2 Gy, 10 Gy and FIR. Of these genes, 22 showed dose- and fractionation-independent upregulation. Immunohistochemistry revealed a robust increase in p65 and cMyc expression in distant heart after SDR and FIR. Immunoblotting revealed increased phosphorylation of p38 after 2 Gy and extracellular signal-regulated kinases 1/2 after 10 Gy in nontargeted heart. In addition, IR exposure significantly enhanced DNA fragmentation in nontargeted heart. Together, these data clearly indicated an induced abscopal response in distant organ after clinically relevant IR doses. More importantly, the results imply that orchestration of NF-κB signal transduction in nontargeted tissues may serve as an effector and could play a key role in induced abscopal responses.

Ascertaining function-specific orchestration of NFκB in response to radiation may reveal a molecular blue-print that dictates induced relapse and metastasis of the neuroblastoma. We recently demonstrated that sustained activation of NFκB caused by ionizing radiation (IR)-initiated TNFα-NFκB feedback signaling leads to radioresistance and recurrence of neuroblastoma. We investigated whether muting IR-triggered or TNFα-dependent second-signaling feedback-dependent NFκB nuclear import results in limiting IR-altered invasion and metastasis. Neuroblastoma cells were exposed to 2 Gy and incubated for 1 h or 24 h. The cells were then treated with an NFκB-targeting peptide blocker, SN50. Upon confirming the blockade in DNA-binding activity, transcription driven transactivation of NFκB and secretion of soluble TNFα, transcriptional alterations of 93 tumor invasion/metastasis genes were assessed by using QPCR profiling and then were selectively validated at the protein level. Exposure to 2 Gy induced 63, 42 and 71 genes in surviving SH-SY5Y, IMR-32 and SK-N-MC cells, respectively. Blocking post-translational nuclear import of NFκB comprehensively inhibited both initial activation of genes (62/63, 34/42 and 65/71) triggered by IR and also TNFα-mediated second signaling-dependent sustained (59/63, 32/42 and 71/71) activation of tumor invasion and metastasis signaling molecules. Furthermore, alterations in the proteins MMP9, MMP2, PYK-2, SPA-1, Dnmt3b, Ask-1, CTGF, MMP10, MTA-2, NF-2, E-Cadherin, TIMP-2 and ADAMTS1 and the results of our scratch-wound assay validate the role of post-translational NFκB in IR-regulated invasion/metastasis. These data demonstrate that IR-induced second-phase (post-translational) NFκB activation mediates TNFα-dependent second signaling and further implies that IR induced NFκB in cells that survive after treatment regulates tumor invasion/metastasis signaling.

Induced radioresistance in the surviving cancer cells after radiotherapy could be associated with clonal selection leading to tumor regrowth at the treatment site. Previously we reported that post-translational modification of IκBα activates NFκB in response to ionizing radiation (IR) and plays a key role in regulating apoptotic signaling. Herein, we investigated the orchestration of NFκB after IR in human neuroblastoma. Both in vitro (SH-SY5Y, SK-N-MC, and IMR-32) and in vivo (xenograft) studies showed that IR persistently induced NFκB DNA binding activity and NFκB-dependent TNFα transactivation and secretion. Approaches including silencing NFκB transcription, blocking post-translational NFκB nuclear import, muting TNF receptor, overexpression, and physiological induction of either NFκB or TNFα precisely demonstrated the initiation and occurrence of NFκB → TNFα → NFκB positive feedback cycle after IR that leads to and sustains NFκB activation. Selective TNF-dependent NFκB regulation was confirmed with futile inhibition of AP-1 and SP-1 in TNF receptor muted cells. Moreover, IR increased both transactivation and translation of Birc1, Birc2, and Birc5 and induced metabolic activity and clonal expansion. This pathway was further defined to show that IR-induced functional p65 transcription (not NFκB1, NFκB2, or c-Rel) is necessary for activation of these survival molecules and associated survival advantage. Together, these results demonstrate for the first time the functional orchestration of NFκB in response to IR and further imply that p65-dependent survival advantage and initiation of clonal expansion may correlate with an unfavorable prognosis of human neuroblastoma.

Purpose: We recently reported that curcumin attenuates ionizing radiation (IR)-induced survival signaling and proliferation in human neuroblastoma cells. Also, in the endothelial system, we have demonstrated that NFκB regulates IR-induced telomerase activity (TA). Accordingly, we investigated the effect of curcumin in inhibiting IR-induced NFκB-dependent hTERT transcription, TA, and cell survival in neuroblastoma cells., Methods and Materials: SK-N-MC or SH-SY5Y cells exposed to IR and treated with curcumin (10-100 nM) with or without IR were harvested after 1 h through 24 h. NFκB-dependent regulation was investigated either by luciferase reporter assays using pNFκB-, pGL3-354-, pGL3-347-, or pUSE-IκBα-Luc, p50/p65, or RelA siRNA-transfected cells. NFκB activity was analyzed using an electrophoretic mobility shift assay and hTERT expression using the quantitative polymerase chain reaction. TA was determined using the telomerase repeat amplification protocol assay and cell survival using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltertrazolium bromide and clonogenic assay., Results: Curcumin profoundly inhibited IR-induced NFκB. Consequently, curcumin significantly inhibited IR-induced TA and hTERT mRNA at all points investigated. Furthermore, IR-induced TA is regulated at the transcriptional level by triggering telomerase reverse transcriptase (TERT) promoter activation. Moreover, NFκB becomes functionally activated after IR and mediates TA upregulation by binding to the κB-binding region in the promoter region of the TERT gene. Consistently, elimination of the NFκB-recognition site on the telomerase promoter or inhibition of NFκB by the IκBα mutant compromises IR-induced telomerase promoter activation. Significantly, curcumin inhibited IR-induced TERT transcription. Consequently, curcumin inhibited hTERT mRNA and TA in NFκB overexpressed cells. Furthermore, curcumin enhanced the IR-induced inhibition of cell survival., Conclusions: These results strongly suggest that curcumin inhibits IR-induced TA in an NFκB dependent manner in human neuroblastoma cells., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Radiation-induced amplification of reactive oxygen species (ROS) may be a sensing mechanism for activation of signaling cascades that influence cell fate. However, the regulated intrinsic mechanisms and targets of low-dose ionizing radiation (LDIR) are still unclear. Accordingly, we investigated the effects of LDIR on NFκB signal transduction and manganese superoxide dismutase (SOD2) activity in mice brain and gut. LDIR resulted in both dose-dependent and persistent NFκB activation in gut and brain. QPCR displayed a dose- and tissue-dependent differential modulation of 88 signaling molecules. With stringent criteria, a total of 15 (2cGy), 43 (10cGy) and 19 (50cGy) genes were found to be commonly upregulated between brain and gut. SOD2 immunostaining showed a LDIR-dose dependent increase. Consistent with the NFκB results, we observed a persistent increase in SOD2 activity after LDIR. Moreover, muting of LDIR-induced NFκB attenuated SOD2 transactivation and cellular localization. These results imply that exposure of healthy tissues to LDIR results in induced NFκB and SOD2 activity and transcriptional activation of NFκB-signal transduction/target molecules. More importantly, the results suggest that NFκB initiates a feedback response through transcriptional activation of SOD2 that may play a key role in the LDIR-induced oxidative stress response and may control the switch that directs cell fate., (2010 Elsevier B.V. All rights reserved.)

Black raspberry extracts (RSE) have been shown to inhibit cancer cell growth and stimulate apoptosis. Also, studies have demonstrated that RSE inhibits transcriptional regulators including NFkappa B. Accordingly, we investigated the effect of RSE in inhibiting radiation (IR) induced NFkappa B mediated radioprotection in breast adenocarcinoma cells. MCF-7 cells were exposed to IR (2Gy), treated with RSE (0.5, 1.0, 2.0 micro g/ml) or treated with RSE (1.0 micro g/ml) followed by IR exposure, and harvested after 1, 3, 6, 24, 48, and 72 h. NFkappa B DNA-binding activity was measured by EMSA and phosphorylated Ikappa Balpha by immunoblotting. Expression of IAP1, IAP2, XIAP and survivin were measured by QPCR and immunoblotting. Cell survival was measured using MTT assay and cell death using Caspase-3/7 activity. Effect of RSE on IR induced MnSOD, TNFalpha, IL-1alpha and MnSOD activity was also determined. RSE inhibited NFkappa B activity in a dose-dependent manner. Also, RSE inhibited IR-induced sustained activation of NFkappa B, and NFkappa B regulated IAP1, IAP2, XIAP, and survivin. In addition, RSE inhibited IR-induced TNFalpha, IL-1alpha, and MnSOD levels and MnSOD activity. RSE suppressed cell survival and enhanced cell death. These results suggest that RSE may act as a potent radiosensitizer by overcoming the effects of NFkappa B mediated radioprotection in human breast cancer cells.

Conceptual approaches of heat-induced cytotoxic effects against tumor cells must address factors affecting therapeutic index, i.e., the relative toxicity for neoplastic versus normal tissues. Accordingly, we investigated the effect of hyperthermia treatment (HT) on the induction of DNA fragmentation, apoptosis, cell-cycle distribution, NFkappaB mRNA expression, DNA-binding activity, and phosphorylation of IkappaBalpha in the normal human Mono Mac 6 (MM6) cells. For HT, cells were exposed to 43 degrees C. FACS analysis showed a 48.5% increase in apoptosis, increased S-phase fraction, and reduced G2 phase fraction after 43 degrees C treatments. EMSA analysis showed a dose-dependent inhibition of NFkappaB DNA-binding activity after HT. This HT-mediated inhibition of NFkappaB was persistent even after 48 h. Immunoblotting analysis revealed dose-dependent inhibition of IkappaBalpha phosphorylation. Similarly, RPA analysis showed that HT persistently inhibits NFkappaB mRNA. These results demonstrate that apoptosis upon HT exposure of MM6 cells is regulated by IkappaBalpha phosphorylation mediated suppression of NFkappaB.

Radiotherapy has been used as an adjunctive local-control modality for high-risk neuroblastoma. However, relapse due to radioresistance affects the success of radiotherapy. Ascertaining the fractionated radiation (FIR) modulated molecular targets is imperative in targeted molecular therapy. Accordingly, we investigated the (i) expression of genes representing six functional pathways; (ii) NFkappaB DNA-binding activity and (iii) expression of radioresponsive molecules after single dose (10 Gy) radiation (SDR) and FIR (2 Gy x 5) in human neuroblastoma cells. Alterations in gene expression were analyzed using QPCR-profiling, NFkappaB activity using electrophoretic mobility shift assay (EMSA) and pIkappaBalpha using immunoblotting. Modulations in TNFalpha, IL-1alpha, pAKT, IAP1, IAP2, XIAP, survivin, MnSOD, BID, Bak, MyD88 and Vegfc were determined using quantitative real-time PCR (Q-PCR) and immunoblotting. Compared to SDR, FIR significantly induced the expression of 25 genes and completely suppressed another 30 genes. Furthermore, FIR induced NFkappaB-DNA-binding activity and IkappaBalpha phosphorylation. Similarly, we observed an induced expression of IAP1, IAP2, XIAP, Survivin, IL-1alpha, MnSOD, Bid, Bak, MyD88, TNFalpha and pAKT in cells exposed to FIR. The results of the study clearly show distinct differences in the molecular response of cells between SDR and FIR. We identified several potential targets confining to NFkappaB signaling cascade that may affect radio-resistance after FIR.

Radiotherapy is considered mandatory for breast cancer patients undergoing conservative surgery and for women at high risk of recurrence. However, relapse due to radio-resistance affects the success of radiotherapy. Ascertaining the fractionated radiation (FIR) modulated molecular targets is important to make tumors more susceptible to molecular targeted therapy. Accordingly, we investigated the (i) expression of 84 genes representing six functional pathways; (ii) NFkappaB DNA binding activity and; (iii) expression of radio-responsive molecules after single dose (10Gy) radiation (SDR) and FIR (2Gyx5). MCF-7 cells exposed to SDR or FIR were analyzed for alterations in gene expression using QPCR-profiling. NFkappaB DNA binding activity was analyzed using EMSA and pIkappaB using immunoblotting. Expression of TNFalpha, IL-1alpha, pAKT, IAP1, IAP2, XIAP, survivin, MnSOD, BID and Bak were determined using QPCR and/or immunoblotting. Compared to SDR, FIR significantly induced 60 genes and completely suppressed 14 genes. Furthermore, FIR induced NFkappaB-DNA binding activity and IkappaBalpha phosphorylation. Like-wise, FIR induced the expression of IAP1, IAP2, XIAP Survivin, MnSOD, TNFalpha, pAKT and IL-1alpha. The results of the study clearly show distinct differences in the molecular response of cells between SDR and FIR exposures. We identified several potential targets that may affect radio-resistance following FIR.

Ascertaining the upstream regulatory mechanisms of hyperthermia-induced apoptosis is important to understand the role of hyperthermia in combined modality cancer therapy. Accordingly, we investigated whether (i) hyperthermia-induced apoptosis is mediated through the nitric oxide (NO) signaling pathway and (ii) inhibition of post-translational modification of IkappaBalpha and down regulation of NFkappaB-DNA binding activity is an intermediate step in NO-dependent apoptosis in MCF-7 breast cancer cells. For hyperthermia treatment, the cells were exposed to 43 degrees C. Intracellular NO levels measured by the fluorescent intensity of DAF-2A and iNOS expression by immunobloting revealed an increased level of iNOS dependent NO production after 43 degrees C. Apoptosis measured by Annexin V expression and cell survival by clonogenic assay showed a 20% increase in apoptosis after 43 degrees C treatments. EMSA analysis showed a dose-dependent inhibition of NFkappaB-DNA binding activity. The hyperthermia-mediated inhibition of NFkappaB was persistent even after 48 h. Inhibition of NO by L-NAME rescued the NFkappaB-DNA binding activity and inhibits heat-induced apoptosis. Similarly, over-expression of NFkappaB by transient transfection inhibits heat-induced apoptosis. These results demonstrate that apoptosis upon hyperthermia exposure of MCF-7 cells is regulated by NO-mediated suppression of NFkappaB., (Copyright 2009 Wiley-Liss, Inc.)

Curcumin has been shown to exhibit growth inhibitory effects and induce apoptosis in a broad range of tumors. Accordingly, we investigated the radiosensitizing effects of curcumin in human neuroblastoma cells. SK-N-MC cells exposed to either 2 Gy alone, or pretreated with curcumin (100 nM) or NFkappaB inhibitor peptide SN50 (50 nM) and exposed to 2 Gy were harvested after 48 h. Radioresistance was measured using clonogenic and MTT assay, NFkappaB DNA-binding activity using electrophoretic mobility shift assay, and apoptosis using Annexin V-FITC staining. Pathway (apoptosis) specific microarrays were used to measure gene expression and validated using QPCR. Radiation markedly enhanced the NFkappaB DNA-binding activity. Pre-treating the cells either with curcumin or SN50 significantly suppressed the radiation induced NFkappaB. Also, curcumin or SN50 pretreatment enhanced the radiation induced inhibition of cell survival. Microarray analysis revealed that curcumin enhanced the radiation induced activation of caspases, other pro-apoptotic and death effector molecules and, inhibit anti-apoptotic/survival molecules. In addition, curcumin markedly suppressed the radiation induced TNF super family genes. These results suggest that curcumin is a potent radiosensitizer and may act by overcoming the effects of radiation-induced NFkappaB mediated pro-survival gene expression in neuroblastoma.

Objective: Vasoactive compounds are known to modulate gene transcription, including nuclear factor kappa B (NF-kappaB), in renal tissues, but the molecular effects of fenoldopam in this setting are not known. The authors used a rat model of surgical acute ischemic nephropathy to test the hypothesis that fenoldopam attenuates ischemia/reperfusion (I/R)-induced NF-kappaB-mediated inflammation., Design: Prospective, single-blind, randomized, controlled animal study., Setting: Academic Department of Anesthesiology laboratory., Subjects: Twenty-four male Sprague-Dawley rats., Interventions: Rats were anesthetized by intraperitoneal administration of 50 mg/kg of urethane and randomly allocated into 4 groups (n = 6 each): sham operation, sham operation with infusion of 0.1 microg/kg/min of fenoldopam, unilateral renal ischemia (1 hour, left renal artery cross-clamping) followed by 4 hours of reperfusion, and unilateral renal I/R with fenoldopam infusion., Measurements and Main Results: Kidney samples were used to measure NF-kappaB DNA-binding activity with an electrophoretic mobility shift assay. NF-kappaB signaling-dependent gene transcription was assessed with microarray analysis, and validated with reverse transcriptase polymerase chain reaction (RT-PCR). Expression of insulin-like growth factor-1 and nitric oxide synthetase-3 messenger RNA (not included in the array) was studied with RT-PCR. NF-kappaB DNA binding activity was significantly higher (p < 0.001) after I/R injury. Of the 96 genes analyzed, 75 were induced and another 8 were suppressed completely (2-fold or greater change v control) after I/R. Treatment with fenoldopam prevented activation of NF-kappaB DNA binding activity (p < 0.001) and attenuated 72 of 75 I/R-induced genes and 3 of 8 I/R-suppressed genes., Conclusion: Data from this rat model of renal I/R suggest that the mechanism by which fenoldopam attenuates I/R-induced inflammation appears to involve inhibition of NF-kappaB translocation and signal transduction.

The objective of this study was to investigate whether heavy ion (56Fe) radiation exposure activates one of the key transcriptional regulators, nuclear factor-kappa B (NF-kappa B), in normal human monocytes (Mono Mac 6 cells: MM6). The study revealed that the exposure of MM6 cells to 56Fe ions resulted in increased NF-kappa B DNA-binding activity. The activation was both dose- and time-dependent, with a maximum response at the 2 h time point after a 0.7 Gy dose. Cells pre-incubated with inhibitors of the phosphorylation and proteasome signaling pathway, completely blocked heavy ion-induced activation of NF-kappa B. These results clearly indicate that 56Fe ions can induce NF-kappa B DNA-binding activity in normal human monocytes, that the activation is rapid and persistent, and that the heavy ion-induced activation of NF-kappa B is mediated through phosphorylation of I-kappa B alpha and the subsequent proteasome-dependent degradation pathway. Since activation of NF-kappa B by extracellular stimuli is implicated in inflammation, infection and cancer induction, as well as in protection of cells against insult, it will be important in subsequent studies to elucidate whether heavy ion-induced NF-kappa B activation is involved in downstream gene expression.