Inflammation as a tumor promoter in cancer induction

Update on the chemopreventive effects of ginger and its phytochemicals

The rhizomes of Zingiber officinale Roscoe (Zingiberaceae), commonly known as ginger, is one of the most widely used spice and condiment. It is also an integral part of many traditional medicines and has been extensively used in Chinese, Ayurvedic, Tibb-Unani, Srilankan, Arabic, and African traditional medicines, since antiquity, for many unrelated human ailments including common colds, fever, sore throats, vomiting, motion sickness, gastrointestinal complications, indigestion, constipation, arthritis, rheumatism, sprains, muscular aches, pains, cramps, hypertension, dementia, fever, infectious diseases, and helminthiasis. The putative active compounds are nonvolatile pungent principles, namely gingerols, shogaols, paradols, and zingerone. These compounds are some of the extensively studied phytochemicals and account for the antioxidant, anti-inflammatory, antiemetic, and gastroprotective activities. A number of preclinical investigations with a wide variety of assay systems and carcinogens have shown that ginger and its compounds possess chemopreventive and antineoplastic effects. A number of mechanisms have been observed to be involved in the chemopreventive effects of ginger. The cancer preventive activities of ginger are supposed to be mainly due to free radical scavenging, antioxidant pathways, alteration of gene expressions, and induction of apoptosis, all of which contribute towards decrease in tumor initiation, promotion, and progression. This review provides concise information from preclinical studies with both cell culture models and relevant animal studies by focusing on the mechanisms responsible for the chemopreventive action. The conclusion describes directions for future research to establish its activity and utility as a human cancer preventive and therapeutic drug. The above-mentioned mechanisms of ginger seem to be promising for cancer prevention; however, further clinical studies are warranted to assess the efficacy and safety of ginger.

Leukocyte infiltrate in gastrointestinal adenocarcinomas is strongly associated with tumor microsatellite instability but not with tumor immunogenicity

PURPOSE

To analyze the correlation of genomic instability with leukocyte infiltrate in gastrointestinal carcinomas (GIACs) and with tumor immunogenicity, e.g., HLA class I cell surface expression defects and galectin-3 and PDL-1 expression.

EXPERIMENTAL DESIGN

Lymphocyte and macrophage infiltrations were immunohistochemically studied in HLA class I negative GIACs with sporadic high-level microsatellite instability (MSI-H) or microsatellite stability (MSS).

RESULTS

Tumors with MSI-H were associated with the following: dense infiltration (CD45, P < 0.001); cytotoxic CD8-positive lymphocytes (P < 0.001); and a complete absence of HLA class I cell surface expression, due to inactivating β2-microglobulin (β2-m) mutation in 50% of cases. In contrast, HLA class I negative tumors with MSS were significantly associated with fewer CD8-positive lymphocytes. There was no association between microsatellite instability and other molecular features of the tumor cells, including expression of galectin-3. Finally, macrophage infiltrate in the tumors was not correlated with microsatellite instability or HLA class I cell surface expression (CD64, P = 0.63; CD163, P = 0.51).

CONCLUSIONS

Microsatellite instability appears to be the most important factor determining the composition, density, and localization of leukocyte infiltrate, which is independent of other molecular features such expression of HLA class I cells, galectin-3, or programmed death ligand-1. Accordingly, the strong intratumoral CD8+ T infiltration of MSI-H tumors may be produced by elevated levels of specific inflammatory chemokines in the tumor microenvironment.

A prospective study of inflammation markers and endometrial cancer risk in postmenopausal hormone nonusers

BACKGROUND

It is hypothesized that inflammation may mediate the relationship between obesity and endometrial cancer risk. We examined the associations of three inflammation markers, C-reactive protein (CRP), interleukin (IL)-6 and tumor necrosis factor (TNF)-α, with risk of endometrial cancer.

METHODS

A case-cohort study was nested within the Women's Health Initiative, a cohort of postmenopausal women. Baseline plasma samples of 151 incident endometrial cancer cases and 301 subcohort subjects not using hormones were assayed.

RESULTS

CRP, but not IL-6 or TNF-α, was positively associated with endometrial cancer risk after adjusting for age and BMI [HR comparing extreme quartiles (HR q(4)-q(1)) = 2.29; 95% CI = 1.13-4.65; P(trend) = 0.012). After additional adjustment for estradiol and insulin, this association was attenuated (HRq(4)-q(1) = 1.70; 95% CI = 0.78-3.68; P(trend) = 0.127). Obesity (BMI ≥ 30 kg/m(2)) was associated with endometrial cancer risk in an age-adjusted model. The obesity effect was reduced by 48%, 67%, and 77% when either estradiol, CRP, or insulin, respectively, was included in the model, and it became null when all three factors were adjusted for simultaneously.

CONCLUSIONS

The association between inflammation, as indicated by a relatively high level of CRP, and endometrial cancer risk may partially be explained by hyperinsulinemia and elevated estradiol. Nevertheless, all three factors contribute to and mediate the link between obesity and endometrial cancer in postmenopausal women not using hormones.

IMPACT

The association between obesity and endometrial cancer risk in postmenopausal women may be attributed to inflammation, insulin resistance, and elevated estrogen.

Protein damage from electrophiles and oxidants in lungs of mice chronically exposed to the tumor promoter butylated hydroxytoluene

The food additive butylated hydroxytoluene (BHT) promotes tumorigenesis in mouse lung. Chronic BHT exposure is accompanied by pulmonary inflammation and several studies indicate that elevated levels of reactive oxygen species (ROS) are involved in its promoting activity. The link between BHT and elevated ROS involves formation of quinone methide (QM) metabolites; these electrophiles form adducts with a variety of lung proteins including several enzymes that protect cells from oxidative stress. Studies in vitro demonstrated that QM alkylation of cytoprotective enzymes is accompanied by inactivation, so an objective of the present investigation was to determine if inactivation also occurs in vivo. Two groups of mice were exposed to BHT by intraperitoneal injection, one for 10 days and the other for 24 days, and proteins from lung cytosols were examined for damage. Analysis by Western blotting demonstrated that BHT treatment caused substantial increases in protein carbonylation, nitration and adduction by 4-hydroxynonenal, confirming the occurrence of sustained oxidative and nitrosative stress over the treatment period required for tumor promotion. Effects of BHT on the activities and/or levels of a representative group of antioxidant/protective enzymes in mouse lung also were assessed; NAD(P)H:quinone reductase and glutathione reductase were unaffected, however carbonyl reductase activity decreased 50-60%. Superoxide dismutase and glutathione peroxidase activities increased 2- and 1.5-fold, respectively, and glutamate-cysteine ligase catalytic subunit expression increased 32-39% relative to untreated mice. Glutathione S-transferase (GST) activity decreased 50-60% but concentrations of the predominant isoforms, GSTM1 and P1, were not affected. GSTP1 was substantially more susceptible than M1 to adduction and inhibition by treatment with BHT-QM in vitro, suggesting that lower GST activity in mice after BHT treatment is due to adduction of the P1 isoform. The results of this study provide additional insight into mechanisms of BHT-induced oxidative damage and further support a link between inflammation and tumor promotion in mouse lung.

Clinical utility of serum interleukin-8 and interferon-alpha in thyroid diseases

Serum interleukin-8 (IL-8) and interferon-alpha (IFN-α) levels have been estimated from a total of 88 individuals of which 19 were disease-free healthy individuals, and 69 were patients with thyroid diseases: goitre (N = 21), autoimmune diseases (N = 16), and carcinomas (N = 32). Both IL-8 and IFN-α were significantly higher in all the patients as compared to healthy individuals. Serum IL-8 levels showed significant positive correlation with disease stage in thyroid cancer patients. Higher serum IL-8 levels were associated with advanced disease stage while no significant correlation was observed between serum IFN-α levels and any of the clinicopathological parameters. IL-8 and IFN-α significantly correlated with each other in anaplastic carcinoma patients. Finally concluding, monitoring the serum IL-8 and IFN-α levels can help differentiate patients with thyroid diseases from healthy individuals, and IL-8 seems to have a role in the pathogenesis of thyroid diseases and may represent a target for innovative diagnostic and therapeutic strategies.

NRF2, cancer and calorie restriction

The transcription factor NF-E2-related factor (NRF2) is a key regulator of several enzymatic pathways, including cytoprotective enzymes in highly metabolic organs. In this review, we summarize the ongoing research related to NRF2 activity in cancer development, focusing on in vivo studies using NRF2 knockout (KO) mice, which have helped in defining the crucial role of NRF2 in chemoprevention. The lower cancer protection observed in NRF2 KO mice under calorie restriction (CR) suggests that most of the beneficial effects of CR on the carcinogenesis process are likely mediated by NRF2. We propose that future interventions in cancer treatment would be carried out through the activation of NRF2 in somatic cells, which will lead to a delay or prevention of the onset of some forms of human cancers, and subsequently an extension of health- and lifespan.

Basic concepts of inflammation and its role in carcinogenesis

While the normal inflammatory cascade is self-limiting and crucial for host protection against invading pathogens and in the repair of damaged tissue, a wealth of evidence suggests that chronic inflammation is the engine driving carcinogenesis. Over a period of almost 150 years the link between inflammation and cancer development has been well established. In this chapter we discuss the fundamental concepts and mechanisms behind normal inflammation as it pertains to wound healing. We further discuss the association of inflammation and its role in carcinogenesis, highlighting the different stages of cancer development, namely tumour initiation, promotion and progression. With both the innate and adaptive arms of the immune system being central to the inflammatory process, we examine the role of a number of immune effectors in contributing to the carcinogenic process. In addition, we highlight the influences of host genetics in altering cancer risk.

The impact of tacrolimus on vascular endothelial growth factor in experimental corneal neovascularization

PURPOSE

To investigate the impact of tacrolimus on vascular endothelial growth factor (VEGF) in experimental corneal neovascularization (NV) immunohistochemically.

MATERIAL AND METHODS

Five groups of seven Wistar albino rats were formed. A silver nitrate cauterization technique was used to induce corneal NV in the study groups, excluding Group 1 (Control Group). Rats in group 1 did not receive any treatment. Rats in group 2 (sham 1) were administered 1 ml of saline intraperitoneally once a day and those in group 3 (sham 2) received one drop of saline four times a day. Rats in group 4 were administered 0.3 mg/kg tacrolimus intraperitoneally once a day. For group 5, 0.3 mg/ml tacrolimus was installed four times a day. Digital photography for each cornea was performed and the percentage area of the NV on the total corneal surface was calculated. The intensity of VEGF immunostaining in the epithelial, the stromal, and endothelial layers was performed in a semi quantitative fashion.

RESULTS

The mean percentages of the neovascularized areas of intraperitoneally and topically tacrolimus-treated groups were lesser than those of the sham groups (p = 0.002, p = 0.038, respectively). The mean intensity of the epithelial VEGF immunostaining of the intraperitoneally tacrolimus-treated group was less than that of its sham group (p = 0.002), while the mean intensity of the stromal VEGF staining of the topically tacrolimus-treated group was lesser than that of its sham group (p = 0.042). The intensities of the endothelial VEGF immunostaining of the intraperitoneally and topically tacrolimus-treated groups were less than those of the sham groups (p = 0.038, p = 0.032).

CONCLUSION

Systemic and topical administration of tacrolimus may be beneficial in the prevention of corneal NV because of its effect on VEGF.

Curcumin improves prostanoid ratio in diabetic mesenteric arteries associated with cyclooxygenase-2 and NF-κB suppression

BACKGROUND

Curcumin, the active ingredient from turmeric rhizomes, has been shown to have a wide range of pharmacological properties including antioxidant and anti-inflammatory effects. Curcumin has been reviewed for its multiple molecular action on inhibiting tumor angiogenesis via its mechanisms of cyclooxygenase (COX)-2, and vascular endothelial growth factor (VEGF) inhibition. In this present study, we aimed to assess the effects of curcumin on preventing diabetes-induced vascular dysfunction in association with COX-2, nuclear factor-κB (NF-κB) expression, and prostanoid production.

METHODS

Twelve-week-old male Wistar rats were separated into five groups: 1) diabetes with 0.9% normal saline (DM-NSS; n =10), 2) diabetes treated with curcumin 30 mg/kg (n =10), 3) diabetes treated with curcumin 300 mg/kg (n =10), 4) the control with 0.9% normal saline (n =10), and 5) the control treated with 300 mg/kg (n =10). Daily oral feeding of curcumin was started at 6 weeks after the streptozotocin injection. Levels of 6-keto prostaglandin (PG) F(1α)and thromboxane (TX) B(2) were determined from mesenteric perfusates using enzyme immunoassay kits. Protein kinase C (PKC)-β II and COX-2 with NF-κB levels were analyzed in the mesenteric arteries by immunofluorescent staining and immunohistochemistry, respectively.

RESULTS

The ratio of 6-keto-PGF(1α)and TXB(2) was significantly decreased in DM-NSS compared with the control (P < 0.05). Double-immunofluorescent staining with specific antibodies for PKC-βII and α-smooth muscle actins showed that the diabetic mesenteric arteries contained increased of PKC-βII within the vascular wall. Also, COX-2 expression and activated NF-κB in the small mesenteric artery of diabetes mellitus rats were markedly increased when compared with the control. Interestingly, curcumin could inhibit the upregulation of all of these biomarkers.

CONCLUSION

These findings show that curcumin can attenuate diabetes-induced vascular dysfunction in association with its potential for COX-2 and NF-κB suppression, PKC inhibition, and improving the ratio of prostanoid products PGI(2)/TXA(2).

Non-Steroidal Anti-Inflammatory Drugs in the Carcinogenesis of the Gastrointestinal Tract

It is estimated that underlying infections and inflammatory responses are linked to 15-20% of all deaths from cancer worldwide. Inflammation is a physiologic process in response to tissue damage resulting from microbial pathogen infection, chemical irritation, and/or wounding. Tissues injured throughout the recruitment of inflammatory cells such as macrophages and neutrophils, generate a great amount of growth factors, cytokines, and reactive oxygen and nitrogen species that may cause DNA damage that in turn predisposes to the transformation from chronic inflammation to neoplasia. Cyclooxygenase (COX), playing a key role in cell homeostasis, angiogenesis and tumourigenesis, may represent the link between inflammation and cancer. Currently COX is becoming a pharmacological target for cancer prevention and treatment.It is estimated that underlying infections and inflammatory responses are linked to 15-20% of all deaths from cancer worldwide. Inflammation is a physiologic process in response to tissue damage resulting from microbial pathogen infection, chemical irritation, and/or wounding. Tissues injured throughout the recruitment of inflammatory cells such as macrophages and neutrophils, generate a great amount of growth factors, cytokines, and reactive oxygen and nitrogen species that may cause DNA damage that in turn predisposes to the transformation from chronic inflammation to neoplasia. Cyclooxygenase (COX), playing a key role in cell homeostasis, angiogenesis and tumourigenesis, may represent the link between inflammation and cancer. Currently COX is becoming a pharmacological target for cancer prevention and treatment.

Old and new generation lipid mediators in acute inflammation and resolution

Originally regarded as just membrane constituents and energy storing molecules, lipids are now recognised as potent signalling molecules that regulate a multitude of cellular responses via receptor-mediated pathways, including cell growth and death, and inflammation/infection. Derived from polyunsaturated fatty acids (PUFAs), such as arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), each lipid displays unique properties, thus making their role in inflammation distinct from that of other lipids derived from the same PUFA. The diversity of their actions arises because such metabolites are synthesised via discrete enzymatic pathways and because they elicit their response via different receptors. This review will collate the bioactive lipid research to date and summarise the findings in terms of the major pathways involved in their biosynthesis and their role in inflammation and its resolution. It will include lipids derived from AA (prostanoids, leukotrienes, 5-oxo-6,8,11,14-eicosatetraenoic acid, lipoxins and epoxyeicosatrienoic acids), EPA (E-series resolvins), and DHA (D-series resolvins, protectins and maresins).

Changes in saliva interleukin-6 levels in patients with oral squamous cell carcinoma

OBJECTIVE

The aim of this study was to elucidate changes in interleukin-6 (IL-6) levels in whole saliva during the treatment of patients with oral squamous cell carcinoma (OSCC).

STUDY DESIGN

Twenty-nine consecutive inpatients with OSCC were enrolled. Stimulated saliva was collected just after hospitalization (period 1), just before main treatment (surgery in 26 cases; period 2), and at the time of discharge (period 3). The mean intervals were 11+/-8 days between periods 1 and 2 and 30+/-18 days between periods 2 and 3. Nineteen age-matched healthy control subjects were also recruited. Interleukin-6 concentrations were measured by a highly sensitive chemiluminescent enzyme immunoassay.

RESULTS

Interleukin-6 was detected in 23 out of 29 samples in the OSCC group in period 1. The concentration of IL-6 was significantly higher in the OSCC group (mean 20.1+/-36.3 pg/mL) than in the control subjects (0.6+/-0.8 pg/mL; P=.003). The mean concentration of IL-6 at period 2 was 43.6+/-95.6 pg/mL, significantly higher than at period 1 (P=.002), and at period 3 was 17.1+/-27.6 pg/mL (P=.52 [compared with period 2]).

CONCLUSIONS

Interleukin-6 was up-regulated in saliva in the OSCC patients. The IL-6 level tended to increase before treatment, and it returned to baseline levels after treatment.

Update of human and mouse matrix metalloproteinase families

Matrix metalloproteinases (MMPs) are a family of zinc proteases that degrade most of the components of the extracellular matrix (ECM). MMPs also have a number of non-traditional roles in processing factors related to cell growth/proliferation, inflammation and more. There are 23 human MMPs and 23 mouse MMPs, most of which share orthology among most vertebrates; other examples have been found in invertebrates and plants. MMPs are named in order of discovery, but also have been grouped by domain structure or by phylogenetic analysis. MMPs are multi-domain proteins which generally contain a signal sequence; propeptide (which keeps the protein inactive until cleaved); catalytic domain; and a hemopexin-like domain (which provides substrate specificity). MMPs are thought to play a role in many disease states, including arthritis, vascular disease, lung injury, wound repair, cancer and various neurodegenerative disorders. Although there has been much clinical interest in MMP inhibitors (MMPIs), few trials have been successful - often due to the broad nature of inhibition and the complex role of different MMPs in a given disease state.

Programmed necrosis induced by asbestos in human mesothelial cells causes high-mobility group box 1 protein release and resultant inflammation

Asbestos carcinogenesis has been linked to the release of cytokines and mutagenic reactive oxygen species (ROS) from inflammatory cells. Asbestos is cytotoxic to human mesothelial cells (HM), which appears counterintuitive for a carcinogen. We show that asbestos-induced HM cell death is a regulated form of necrosis that links to carcinogenesis. Asbestos-exposed HM activate poly(ADP-ribose) polymerase, secrete H(2)O(2), deplete ATP, and translocate high-mobility group box 1 protein (HMGB1) from the nucleus to the cytoplasm, and into the extracellular space. The release of HMGB1 induces macrophages to secrete TNF-alpha, which protects HM from asbestos-induced cell death and triggers a chronic inflammatory response; both favor HM transformation. In both mice and hamsters injected with asbestos, HMGB1 was specifically detected in the nuclei, cytoplasm, and extracellular space of mesothelial and inflammatory cells around asbestos deposits. TNF-alpha was coexpressed in the same areas. HMGB1 levels in asbestos-exposed individuals were significantly higher than in nonexposed controls (P < 0.0001). Our findings identify the release of HMGB1 as a critical initial step in the pathogenesis of asbestos-related disease, and provide mechanistic links between asbestos-induced cell death, chronic inflammation, and carcinogenesis. Chemopreventive approaches aimed at inhibiting the chronic inflammatory response, and especially blocking HMGB1, may decrease the risk of malignant mesothelioma among asbestos-exposed cohorts.

Inhibitory effect of magnolol on TPA-induced skin inflammation and tumor promotion in mice

Magnolol has been reported to have an anti-inflammatory and antitumor effect in vitro and in vivo. Herein, we report the investigation of the inhibitory effects of magnolol on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in mouse skin. We found that the topical application of magnolol effectively inhibited the transcriptional activation of iNOS and COX-2 mRNA and proteins in mouse skin stimulated by TPA. Pretreatment with magnolol resulted in the reduction of TPA-induced nuclear translocation of the nuclear factor-kappaB (NFkappaB) subunit and DNA binding by blocking the phosphorylation of IkappaBalpha and p65 and subsequent degradation of IkappaBalpha. In addition, magnolol can suppress TPA-induced activation of extracellular signal-regulated kinase (ERK)1/2, p38 mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinase (PI3K)/Akt, which are upstream of NFkappaB. Moreover, magnolol significantly inhibited 7,12-dimethylbene[a]anthracene (DMBA)/TPA-induced skin tumor formation by reducing the tumor multiplicity, tumor incidence, and tumor size of papillomas at 20 weeks. All these results revealed that magnolol is an effective antitumor agent and that its inhibitory effect is through the down-regulation of inflammatory iNOS and COX-2 gene expression in mouse skin, suggesting that magnolol is a novel functional agent capable of preventing inflammation-associated tumorigenesis.

Effects of IL-1 molecules on growth patterns of 3-MCA-induced cell lines: an interplay between immunogenicity and invasive potential

The balance between inflammation and immunity is cardinal for the outcome of the malignant process. Local attenuated inflammatory responses mediated by innate cells may provide accessory signals for the development of acquired immunity against malignant cells. In contrast, excessive inflammatory responses accompany tumorigenesis and tumor invasiveness, by the induction of immunosuppression. In the present study, we have assessed the role of tumor cell-derived IL-1 in determining the invasive versus immunostimulatory potential of tumor cells. For this purpose, we have used 3-MCA-induced fibrosarcoma cell lines from IL-1 knockout (KO) versus control mice. Cell lines with no IL-1 failed to establish tumors in intact mice, while lines obtained from control mice were invasive and induced a potent angiogenic response. In contrast, cell lines from IL-1KO mice were more immunogenic. SDF-1 and IL-6, each induced by IL-1, were the two major cytokines whose levels differed in cell lines with or without IL-1. We could not detect differences in cell surface markers related to immunogenicity, such as MHC Class I, co-stimulatory, or adhesion molecules between both types of cells. However, more T-cells were observed at the inoculation site of tumor cells devoid of IL-1 and more pronounced parameters related to anti-tumor immunity were observed in the spleen (IL-12 and IFNgamma) of these mice, compared to mice bearing tumors derived from control mice, where host-derived IL-1 is present. In addition, injection of tumor cells devoid of IL-1, which failed to grow in mice, induced an anti-tumor cell immune memory, while in mice injected with tumor cells from control mice; no immune memory could be detected. From the results, it seems that IL-1 is a crucial factor in determining the balance between immunity and inflammation in tumor-bearing mice. This suggests that manipulation of IL-1 could be useful in anti-tumor therapy, by reducing invasiveness and promoting immunity against the malignant cells.

Role of inflammation and oxidative stress mediators in gliomas

Gliomas are the most common primary brain tumors of the central nervous system. Despite relevant progress in conventional treatments, the prognosis of such tumors remains almost invariably dismal. The genesis of gliomas is a complex, multistep process that includes cellular neoplastic transformation, resistance to apoptosis, loss of control of the cell cycle, angiogenesis, and the acquisition of invasive properties. Among a number of different biomolecular events, the existence of molecular connections between inflammation and oxidative stress pathways and the development of this cancer has been demonstrated. In particular, the tumor microenvironment, which is largely orchestrated by inflammatory molecules, is an indispensable participant in the neoplastic process, promoting proliferation, survival and migration of such tumors. Proinflammatory cytokines, such as tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma, as well as chemokines and prostaglandins, are synthesized by resident brain cells and lymphocytes invading the affected brain tissue. Key mediators of cancer progression include nuclear factor-kappaB, reactive oxygen and nitrogen species, and specific microRNAs. The collective activity of these mediators is largely responsible for a pro-tumorigenic response through changes in cell proliferation, cell death, cellular senescence, DNA mutation rates, DNA methylation and angiogenesis. We provide a general overview of the connection between specific inflammation and oxidative stress pathway molecules and gliomas. The elucidation of specific effects and interactions of these factors may provide the opportunity for the identification of new target molecules leading to improved diagnosis and treatment.

Anti-carcinogenic properties of curcumin on colorectal cancer

Curcumin has been used in traditional Indian medicine for many centuries for its anti-inflammatory and anti-carcinogenic properties. There has been some promising research concerning curcumin as a safe therapeutic agent for many cancers, colorectal cancer being among them. This has been shown through research in cell cultures, animal models, and humans. At this time, it appears that curcumin’s anti-carcinogenic properties are most likely due to its effects on multiple molecular targets, such as nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and activator protein 1 (AP-1). NF-κB and AP-1 are both major transcription factors that regulate inflammation and thus affect cell proliferation, differentiation and even apoptosis. Curcumin has also been shown to affect a variety of other key players involved in carcinogenesis, such as cyclooxygenase-2, matrix metallopeptidases 2 and 9 and tumor necrosis factor α induced vascular cell adhesion molecule, just to name a few. Although many molecular targets are involved, curcumin has been well tolerated in many studies: doses up to 8 g a day have been confirmed to be safe for humans. In this brief review, we will examine the current studies and literature and touch upon many molecular pathways affected by curcumin, and demonstrate the exciting possibility of curcumin as a chemopreventive agent for colorectal cancer.

Decursinol angelate blocks transmigration and inflammatory activation of cancer cells through inhibition of PI3K, ERK and NF-kappaB activation

Inflammation is known to be closely associated with the development of cancer. Decursinol angelate (DA), a coumarin compound isolated from Angelica gigas and related compounds have been shown to possess potent anti-inflammatory activities. However, little is known about their effects on the inflammatory processes associated with cancer. In this study, the anti-inflammatory effect of DA was evaluated in cancer cell lines with respect to cellular invasion through the extracellular matrix (ECM) and the expression of pro-inflammatory mediators such as cytokine, cell adhesion molecules and matrix metalloproteinase (MMP)-9. DA inhibited the invasion of fibrosarcoma cell line, HT1080 and breast cancer cell line, MDA-MB-231 in the Matrigel invasion assay. DA-mediated suppression of cancer cell invasion was accomplished by suppression of PI3K activity known to be associated with cytoskeletal rearrangement related to cellular migration. DA also suppressed the adhesion of cancer cells to ECM mediated by down-regulation of beta(1)-integrin expression levels. Furthermore, DA inhibited the expression of pro-inflammatory cytokines and MMP-9 through suppression of PI3K, ERK and NF-kappaB activation. These results demonstrate that DA suppresses invasion and inflammatory activation of cancer cells through modulation of PI3K/AKT, ERK and NF-kappaB. These anti-inflammatory activities of DA may contribute to its anti-cancer activity.

The role of cyclooxygenase-2 in cell proliferation and cell death in human malignancies

It is well admitted that the link between chronic inflammation and cancer involves cytokines and mediators of inflammatory pathways, which act during the different steps of tumorigenesis. The cyclooxygenases (COXs) are a family of enzymes, which catalyze the rate-limiting step of prostaglandin biosynthesis. This family contains three members: ubiquitously expressed COX-1, which is involved in homeostasis; the inducible COX-2 isoform, which is upregulated during both inflammation and cancer; and COX-3, expressed in brain and spinal cord, whose functions remain to be elucidated. COX-2 was described to modulate cell proliferation and apoptosis mainly in solid tumors, that is, colorectal, breast, and prostate cancers, and, more recently, in hematological malignancies. These findings prompt us to analyze here the effects of a combination of COX-2 inhibitors together with different clinically used therapeutic strategies in order to further improve the efficiency of future anticancer treatments. COX-2 modulation is a promising field investigated by many research groups.

Triggering of TLR7 and TLR8 expressed by human lung cancer cells induces cell survival and chemoresistance

Compelling evidence suggests that inflammation, cell survival, and cancer are linked, with a central role played by NF-kappaB. Recent studies implicate some TLRs in tumor development based on their ability to facilitate tumor growth; however, to our knowledge, involvement of neither TLR7 nor TLR78 has yet been demonstrated. Here we have demonstrated expression of TLR7 and TLR8, the natural receptors for single-stranded RNA, by tumor cells in human lung cancer in situ and in human lung tumor cell lines. Stimulation with TLR7 or TLR8 agonists led to activated NF-kappaB, upregulated expression of the antiapoptotic protein Bcl-2, increased tumor cell survival, and chemoresistance. Transcriptional analysis performed on human primary lung tumor cells and TLR7- or TLR8-stimulated human lung tumor cell lines revealed a gene expression signature suggestive of chronic stimulation of tumor cells by TLR ligands in situ. Together, these data emphasize that TLR signaling can directly favor tumor development and further suggest that researchers developing anticancer immunotherapy using TLR7 or TLR8 agonists as adjuvants should take into account the expression of these TLRs in lung tumor cells.

Naturally occurring phenolic acids inhibit 12-O-tetradecanoylphorbol-13-acetate induced NF-kappaB, iNOS and COX-2 activation in mouse epidermis

The aim of this study was to investigate the effects of naturally occurring protocatechuic, chlorogenic and tannic acids on the skin tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA), induced NF-kappaB in mouse epidermis. The topical application of these phenolics 15min prior to TPA resulted in a significant decrease in the NF-kappaB activation which was measured in terms of p65-DNA binding. Tannic acid was the most potent inhibitor of the TPA-stimulated p65-DNA binding, while chlorogenic acid was the least effective compound. Tannic acid also reduced the most the NF-kappaB p65 subunit translocation from cytosol to the nucleus and enhanced the retention of IkappaBalpha in the cytosol. Although protocatechuic acid decreased p65-DNA binding, it did not affect TPA-stimulated degradation of IkappaBalpha. All the tested compounds inhibited the IkappaBalpha kinase (IKK) activity in mouse epidermis. Tannic acid was the most potent inhibitor and protocatechuic acid the weakest. Tannic and chlorogenic acids reduced the TPA-induced C-L activity of proteasome 20S to a similar extent. The blockade of upstream kinase IKK signaling by tannic acid, but also by protocatechuic acid, inhibited the enzyme level and the activity of COX-2. Protocatechuic acid also diminished the level and activity of TPA-induced iNOS, which might be related to its weak effect on IkappaBalpha degradation. Our earlier studies demonstrated that these compounds, particularly tannic acid, reduced the formation of the polycyclic aromatic hydrocarbon-DNA adducts in vitro and in vivo in mouse epidermis. The results of our present study indicate that the compounds which reduce the formation of electrophilic PAH metabolites may also diminish NF-kappaB activation. Thus, the phenolic acids, particularly tannic acid, by affecting the key events of initiation and promotion stage of carcinogenesis, have become of great interest for the prevention of cancer.

Exploring the link between microorganisms and oral cancer: a systematic review of the literature

The majority of cases of oral cancer have been related to tobacco use and heavy alcohol consumption. However, the incidence of oral cavity carcinoma appears to be increasing in many parts of the world in a manner that it is difficult to explain with traditional risk factors alone. Meanwhile, interest in the possible relationships between microorganisms and the different stages of cancer development has been rising and numerous mechanisms by which bacteria and yeast may initiate or promote carcinogenesis are currently under investigation. In particular, a persuasive body of evidence suggests a possible etiological role involving the metabolism and production of carcinogenic products, such as acetaldehyde. Other suggested mechanisms include the induction of chronic inflammation and direct interference with eukaryotic cell cycle and signaling pathways. This review aims to summarize the known associations between microbial infection and cancer and draw attention to how they may relate to oral carcinoma.

Chronic bacterial inflammation induces prostatic intraepithelial neoplasia in mouse prostate

Background:

Although the aetiology of prostate cancer remains unknown, we hypothesised that chronic bacterial insult has a major role in prostate carcinogenesis.

Methods:

Male C3H/HeOuJ mice, infected with phosphate-buffered saline or Escherichia coli bacteria, were killed at 5 days, or at 12 or 26 weeks. Harvested prostate tissues were evaluated for inflammatory responses and immunostained for neoplastic transformation markers.

Results:

All infected mice developed bacterial prostatitis. Control mice had no prostate infections or inflammation. Mice infected for 5 days showed foci of acute inflammation with infiltrating neutrophils and epithelial necrotic debris in the prostatic glandular lumen. All mice infected for 12 weeks had evidence of chronic inflammation with dense inflammatory infiltrates in the stroma. The prostatic epithelium showed varying degrees of atypical hyperplasia with increased epithelial cell layers and cytological atypia. At 26 weeks, the dysplastic changes were more pronounced and mimicked a prostatic intraepithelial neoplasia and high-grade dysplasia. Prostatic glands exhibiting reactive dysplasia had a stronger staining for oxidative DNA damage, increased epithelial cell proliferation, and a decrease in androgen receptor, GSTP1, p27^Kip1, and PTEN expression, when compared with control prostate glands.

Conclusion:

These data demonstrate that chronic inflammation induces focal prostatic glandular atypia and suggest a potential linkage between inflammation and prostatic neoplasia.

Antioxidant and anti-inflammatory properties of cancer preventive peptide lunasin in RAW 264.7 macrophages

Oxidative stress and inflammation are two of the most critical factors implicated in carcinogenesis and other degenerative disorders. We have investigated how lunasin, a known anti-cancer seed peptide, affect these factors. This peptide inhibits linoleic acid oxidation and acts as 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenger. Furthermore, using LPS-stimulated RAW 264.7 macrophages, we have demonstrated that lunasin reduces, in a significant dose-dependent manner, the production of reactive oxygen species (ROS) by LPS-induced macrophages. Lunasin also inhibits the release of pro-inflammatory cytokines (tumor necrosis factor-alpha [TNF-alpha] and interleukine-6 [IL-6]). On the basis of these potent antioxidant and anti-inflammatory properties, we propose lunasin not only as a cancer preventive and therapeutic agent but also as an agent against other inflammatory-related disorders.

Antagonistic effects of aspirin and folic acid on inflammation markers and subsequent risk of recurrent colorectal adenomas

The Aspirin/Folate Polyp Prevention Trial found that aspirin, but not folic acid, reduced recurrence of colorectal adenomas. This study examined whether treatment effects on inflammation markers explained the trial results. The trial had a factorial design with three aspirin (placebo, 81, and 325 mg/d) and two folic acid (placebo and 1 mg/d) groups. There were 884 subjects who had colonoscopic evaluation for adenomas at year 3 and plasma levels of C-reactive protein (CRP), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), soluble TNF receptor type II (sTNF-R2), and IL-1 receptor antagonist (IL-1Ra) measured at baseline and year 3. Among individuals not receiving folic acid, there was a 4% decrease (mean ratio of year 3 to baseline levels = 0.96, 95% confidence interval [CI] = 0.82 to 1.14) in CRP for a period of 3 years in the 325 mg of aspirin group vs a 20% increase (mean ratio = 1.20, 95% CI = 1.03 to 1.41) in the placebo group (P = .027). By contrast, the reverse was observed among individuals who also received folic acid (P(interaction) = .013). Changes in inflammation markers were not associated with adenoma recurrence. Low-dose aspirin (325 mg/d) is beneficial in stabilizing CRP levels, which may be abrogated by folate. Nevertheless, inflammation markers do not mediate the chemopreventive effect of aspirin on colorectal adenomas.

Nonischemic cerebral venous hypertension promotes a pro-angiogenic stage through HIF-1 downstream genes and leukocyte-derived MMP-9

Cerebral venous hypertension (VH) and angiogenesis are implicated in the pathogenesis of brain arteriovenous malformation and dural arteriovenous fistulae. We studied the association of VH and angiogenesis using a mouse brain VH model. Sixty mice underwent external jugular vein and common carotid artery (CCA) anastomosis (VH model), CCA ligation, or sham dissection (n=20). Hypoxia-inducible factor-1alpha (HIF-1alpha), vascular endothelial growth factor (VEGF) and stromal-cell-derived factor-1alpha (SDF-1alpha) expression, and matrix metalloproteinase (MMP) activity were analyzed. We found VH animals had higher (P<0.05) sagittal sinus pressure (8+/-1 mm Hg) than control groups (1+/-1 mm Hg). Surface cerebral blood flow and mean arterial pressure did not change. Hypoxia-inducible factor-1alpha, VEGF, and SDF-1alpha expression increased (P<0.05). Neutrophils and MMP-9 activity increased 10-fold 1 day after surgery, gradually decreased afterward, and returned to baseline 2 weeks after surgery. Macrophages began to increase 3 days after surgery (P<0.05), which coincided with the changes in SDF-1alpha expression. Capillary density in the parasagittal cortex increased 17% compared with the controls. Our findings suggest that mild nonischemic VH results in a pro-angiogenic stage in the brain by upregulating HIF-1 and its downstream targets, VEGF and SDF-1alpha, increasing leukocyte infiltration and MMP-9 activity.

Breast-cancer-associated metastasis is significantly increased in a model of autoimmune arthritis

Introduction

Sites of chronic inflammation are often associated with the establishment and growth of various malignancies including breast cancer. A common inflammatory condition in humans is autoimmune arthritis (AA) that causes inflammation and deformity of the joints. Other systemic effects associated with arthritis include increased cellular infiltration and inflammation of the lungs. Several studies have reported statistically significant risk ratios between AA and breast cancer. Despite this knowledge, available for a decade, it has never been questioned if the site of chronic inflammation linked to AA creates a milieu that attracts tumor cells to home and grow in the inflamed bones and lungs which are frequent sites of breast cancer metastasis.

Methods

To determine if chronic inflammation induced by autoimmune arthritis contributes to increased breast cancer-associated metastasis, we generated mammary gland tumors in SKG mice that were genetically prone to develop AA. Two breast cancer cell lines, one highly metastatic (4T1) and the other non-metastatic (TUBO) were used to generate the tumors in the mammary fat pad. Lung and bone metastasis and the associated inflammatory milieu were evaluated in the arthritic versus the non-arthritic mice.

Results

We report a three-fold increase in lung metastasis and a significant increase in the incidence of bone metastasis in the pro-arthritic and arthritic mice compared to non-arthritic control mice. We also report that the metastatic breast cancer cells augment the severity of arthritis resulting in a vicious cycle that increases both bone destruction and metastasis. Enhanced neutrophilic and granulocytic infiltration in lungs and bone of the pro-arthritic and arthritic mice and subsequent increase in circulating levels of proinflammatory cytokines, such as macrophage colony stimulating factor (M-CSF), interleukin-17 (IL-17), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and tumor necrosis factor-alpha (TNF-alpha) may contribute to the increased metastasis. Treatment with anti-IL17 + celecoxib, an anti-inflammatory drug completely abrogated the development of metastasis and significantly reduced the primary tumor burden.

Conclusions

The data clearly has important clinical implications for patients diagnosed with metastatic breast cancer, especially with regards to the prognosis and treatment options.

IFNgamma promotes papilloma development by up-regulating Th17-associated inflammation

IFNgamma plays a crucial role in immunity against a variety of transplanted tumors and methylcholanthrene-mediated tumorigenesis in mice. However, it is not clear whether and how endogenous IFNgamma influences 7,12-dimethylbenz(a)anthracene (DMBA)-induced and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced papilloma development. We found here that IFNgamma expression was markedly up-regulated shortly after DMBA/TPA application to the skin. Surprisingly, neutralizing IFNgamma activity in vivo did not increase but rather decreased tumor development. Furthermore, IFNgamma receptor-deficient mice were also more resistant to papilloma development than their counterparts were. IFNgamma acted mainly in the promotion stage of papilloma development by enhancing TPA-induced leukocyte infiltration and epidermal hyperproliferation. The up-regulation of tumor necrosis factor alpha, interleukin (IL)-6, and transforming growth factor beta was largely dependent on host IFNgamma responsiveness. Remarkably, up-regulation of both IL-17 expression in the skin and T helper 17 (Th17) cell number in draining lymph nodes after DMBA/TPA treatment was dependent on IFNgamma signaling. Depletion of IL-17 not only decreased the DMBA/TPA-induced inflammation and keratinocyte proliferation but also delayed papilloma development. These results show that IFNgamma, under certain conditions, may promote tumor development by enhancing a Th17-associated inflammatory reaction.

A novel prodrug of 4'-geranyloxy-ferulic acid suppresses colitis-related colon carcinogenesis in mice

The inhibitory effects of a novel prodrug, 3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoyl-L-alanyl-L-proline (GAP), of the secondary metabolite 4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoic acid (4'-geranyloxy-ferulic acid), on colon carcinogenesis was investigated using an azoxymetahen (AOM)/dextran sodium sulfate (DSS) model. GAP was synthetically derived from ferulic acid. Male CD-1 (ICR) mice initiated with a single intraperitoneal injection of azoxymethane (10 mg/kg body weight) were promoted by 1% (wt/vol) DSS in drinking water for 7 days. They were then given modified AIN-76A diet containing 0.01% or 0.05% GAP for 17 wk. At Week 20, the development of colonic adenocarcinoma was significantly inhibited by GAP feeding at dose levels of 0.01% [60% incidence (P = 0.0158) with a multiplicity of and 1.13 +/- 1.13 (P < 0.05)] and 0.05% [53% incidence (P = 0.0057) with a multiplicity of 0.08 +/- 1.08 (P < 0.01)], when compared to the AOM/DSS group (95% incidence with a multiplicity of 3.10 +/- 3.06). Dietary GAP modulated the mitotic and apoptotic indexes in the crypt cells and lowered 8-hydroxy-2'-deoxyguanosine (8-OHdG)-positive cells in the colonic mucosa. Urinary level of 8-OHdG was lowered by GAP feeding. Additionally, dietary GAP elevated the immunoreactivity of an inducible form of heme oxygenase 1 in the colonic mucosa. Our results indicate that GAP is able to inhibit colitis-related colon carcinogenesis by modulating proliferation and oxidative stress in mice.

Use of cannabinoid receptor agonists in cancer therapy as palliative and curative agents

Cannabinoids (the active components of Cannabis sativa) and their derivatives have received renewed interest in recent years due to their diverse pharmacological activities. In particular, cannabinoids offer potential applications as anti-tumour drugs, based on the ability of some members of this class of compounds to limit cell proliferation and to induce tumour-selective cell death. Although synthetic cannabinoids may have pro-tumour effects in vivo due to their immunosuppressive properties, predominantly inhibitory effects on tumour growth and migration, angiogenesis, metastasis, and also inflammation have been described. Emerging evidence suggests that agonists of cannabinoid receptors expressed by tumour cells may offer a novel strategy to treat cancer. In this chapter we review the more recent results generating interest in the field of cannabinoids and cancer, and provide novel suggestions for the development, exploration and use of cannabinoid agonists for cancer therapy, not only as palliative but also as curative drugs.

Associations of circulating C-reactive protein and interleukin-6 with cancer risk: findings from two prospective cohorts and a meta-analysis

OBJECTIVE

We investigated the associations of circulating C-reactive protein (CRP) and interleukin-6 (IL-6) with cancer risk.

METHODS

We examined the associations of CRP and IL-6 with incident cancer in two prospective cohorts, the British Women's Heart and Health Study (4,286 women aged 60-80) and the Caerphilly Cohort (2,398 men aged 45-59) using Cox regression and pooled our findings with previous prospective studies' in fixed and random effects meta-analyses.

RESULTS

CRP and IL-6 were associated with some incident cancers in our cohorts, but the numbers of cancer cases were small. In our meta-analyses elevated CRP was associated with an increased overall risk of cancer (random effects estimate (RE): 1.10, 95% CI: 1.02, 1.18) and lung cancer (RE: 1.32, 95% CI: 1.08, 1.61). Its associations with colorectal (RE: 1.09, 95% CI: 0.98, 1.21) and breast cancer risks (RE: 1.10, 95% CI: 0.97, 1.26) were weaker. CRP appeared unrelated to prostate cancer risk (RE: 1.00 0.88, 1.13). IL-6 was associated with increased lung and breast cancer risks and decreased prostate cancer risk, and was unrelated to colorectal cancer risk.

CONCLUSIONS

Our findings suggest an etiological role for CRP and IL-6 in some cancers. Further large prospective and genetic studies would help to better understand this role.

Glycine- and proline-rich glycoprotein regulates the balance between cell proliferation and apoptosis for ACF formation in 1,2-dimethylhydrazine-treated A/J mice

The objective of this study was to investigate the chemopreventive potentials of glycine- and proline-rich glycoprotein (SNL glycoprotein, 150-kDa) isolated from Solanum nigrum Linne on formation of colonic aberrant crypt foci (ACF) induced by 1,2-dimethylhydrazine (DMH, 20 mg/kg) in A/J mice. Administration of SNL glycoprotein inhibited phosphorylation of extracellular signal-regulated kinase (ERK), expression of colonic proliferating cell nuclear antigen (PCNA), and frequency of colonic ACF in DMH-stimulated mice colon carcinogenesis. In addition, SNL glycoprotein increased expression of cyclin-dependent kinase inhibitors (p21(WAF/Cip1) and p27(Kip1)), whereas reduced expression of precursor form of apoptosis-related proteins [pro-caspase-3 and pro-poly(ADP-ribose)polymerase (PARP)] in the mice. Interestingly, the results in this study revealed that SNL glycoprotein has suppressive effects on activity of nuclear factor-kappa B (NF-kappaB), whereas it has stimulatory effect on the expression of p53, accompanying inhibitory effects on expression of NF-kappaBp50, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha in DMH-stimulated ACF formation. Also, SNL glycoprotein has inhibitory effects on the formation of thiobarbituric acid reactive substances (TBARS), on the production of inducible nitric oxide (NO), and on the release of lactate dehydrogenase (LDH) in the mice plasma. Collectively, our findings in this study suggest that SNL glycoprotein has chemopreventive activity via modulation of cell proliferation and apoptosis in DMH-treated A/J mice.

Toll-like receptors and their role in carcinogenesis and anti-tumor treatment

Toll-like receptors (TLRs) have been described as major components of the innate immune system, recognizing the conserved molecular structures found in the large groups of pathogens called pathogen-associated molecular patterns (PAMPs). TLR expression is ubiquitous, from epithelial to immunocompetent cells. TLR ligation triggers several adapter proteins and downstream kinases, leading to the induction of key pro-inflammatory mediators but also anti-inflammatory and anti-tumor cytokines. The result of this activation goes beyond innate immunity to shape the adaptive responses against pathogens and tumor cells, and maintains host homeostasis via cell debris utilization. TLRs have already become potent targets in infectious disease treatment and vaccine therapy and in neoplastic disease treatment, due to their ability to enhance antigen presentation. However, some studies show the dual effect of TLR stimulation on malignant cells: they can be proapoptotic or promote survival under different conditions. It is therefore crucial to design further studies assessing the biology of these receptors in normal and transformed cells. The established role of TLRs in human disease therapy is based on TLR7 and TLR4 agonists, respectively for the novel treatment of some types of skin cancer and for the anti-hepatitis B virus vaccine. Some clinical trials involving TLR agonists as potent enhancers of the anti-tumor response in solid tumors have begun.

Ginger extract (Zingiber officinale) has anti-cancer and anti-inflammatory effects on ethionine-induced hepatoma rats

OBJECTIVE

To evaluate the effect of ginger extract on the expression of NFkappaB and TNF-alpha in liver cancer-induced rats.

METHODS

Male Wistar rats were randomly divided into 5 groups based on diet: i) control (given normal rat chow), ii) olive oil, iii) ginger extract (100mg/kg body weight), iv) choline-deficient diet + 0.1% ethionine to induce liver cancer and v) choline-deficient diet + ginger extract (100mg/kg body weight). Tissue samples obtained at eight weeks were fixed with formalin and embedded in paraffin wax, followed by immunohistochemistry staining for NFkappaB and TNF-alpha.

RESULTS

The expression of NFkappaB was detected in the choline-deficient diet group, with 88.3 +/- 1.83% of samples showing positive staining, while in the choline-deficient diet supplemented with ginger group, the expression of NFkappaB was significantly reduced, to 32.35 +/- 1.34% (p<0.05). In the choline-deficient diet group, 83.3 +/- 4.52% of samples showed positive staining of TNF-alpha, which was significantly reduced to 7.94 +/- 1.32% (p<0.05) when treated with ginger. There was a significant correlation demonstrated between NFkappaB and TNF-alpha in the choline-deficient diet group but not in the choline-deficient diet treated with ginger extract group.

CONCLUSION

In conclusion, ginger extract significantly reduced the elevated expression of NFkappaB and TNF-alpha in rats with liver cancer. Ginger may act as an anti-cancer and anti-inflammatory agent by inactivating NFkappaB through the suppression of the pro-inflammatory TNF-alpha.

A role for the substance P/NK-1 receptor complex in cell proliferation and apoptosis in oral lichen planus

OBJECTIVES

To determine whether substance P (SP) and NK-1 receptor (NK-1R) are expressed in oral lichen planus (OLP) and are related to cell proliferation and apoptosis in this disease.

MATERIAL AND METHODS

Tissue samples from 50 OLP patients and 26 healthy controls were studied. Immunohistochemistry was performed with anti-SP, anti-NK-1R, anti-ki-67 and anti-caspase-3 monoclonal antibodies and the clinical and pathological data of the OLP patients were evaluated.

RESULTS

With the exception of NK-1R expression in epithelial cell membrane and cytoplasm, all markers were more frequently present in OLP patients than in controls (P < 0.05). Higher cytoplasmatic expression of NK-1R was associated with higher epithelial expression of caspase-3 (P < 0.05). Higher epithelial expression of NK-1R and SP was associated with higher suprabasal and basal epithelial expression of ki-67 (P < 0.05 and P < 0.005, respectively).

CONCLUSIONS

Actions of the SP/NK-1R complex may contribute to the immune disorder underlying OLP and trigger stimuli to induce cell proliferation. These results indicate that this complex might play a role in the malignant transformation of OLP.

Dye-doped silica nanoparticle labels/protein microarray for detection of protein biomarkers

We report a dye-encapsulated silica nanoparticle as a label, with the advantages of high fluorescence intensity, photostability, and biocompatibility, in conjunction with microarray technology for sensitive immunoassay of a biomarker, interleukin-6 (IL-6), on a microarray format. The tris(2,2'-bipyridyl)ruthenium(ii) chloride hexahydrate (Rubpy) dye was incorporated into silica nanoparticles using a simple one-step microemulsion synthesis. In this synthesis process, Igepal CA520 was used as the surfactant, therefore, no requirement of cosolvent during the synthesis and the particle size was reduced comparing to the commonly used Triton surfactant system. The nanoparticles are uniform in size with a diameter of 50 nm. The microarray fluorescent immunoassay approach based on dye-doped silica nanoparticle labels has high sensitivity for practical applications with a limit of detection for IL-6 down to 0.1 ng mL(-1). The calibration curve is linear over the range from 0.1 ng mL(-1) to 10 ng mL(-1). Furthermore, results illustrated that the assay is highly specific for IL-6 in the presence of range of cytokines or proteins. The RuDS dye-labeled nanoparticles in connection with protein microarrays show the promise for clinical diagnosis of biomarkers.

Expression-based Pathway Signature Analysis (EPSA): mining publicly available microarray data for insight into human disease

BACKGROUND

Publicly available data repositories facilitate the sharing of an ever-increasing amount of microarray data. However, these datasets remain highly underutilized. Reutilizing the data could offer insights into questions and diseases entirely distinct from those considered in the original experimental design.

METHODS

We first analyzed microarray datasets derived from known perturbations of specific pathways using the samr package in R to identify specific patterns of change in gene expression. We refer to these pattern of gene expression alteration as a "pathway signatures." We then used Spearman's rank correlation coefficient, a non-parametric measure of correlation, to determine similarities between pathway signatures and disease profiles, and permutation analysis to evaluate false discovery rate. This enabled detection of statistically significant similarity between these pathway signatures and corresponding changes observed in human disease. Finally, we evaluated pathway activation, as indicated by correlation with the pathway signature, as a risk factor for poor prognosis using multiple unrelated, publicly available datasets.

RESULTS

We have developed a novel method, Expression-based Pathway Signature Analysis (EPSA). We demonstrate that ESPA is a rigorous computational approach for statistically evaluating the degree of similarity between highly disparate sources of microarray expression data. We also show how EPSA can be used in a number of cases to stratify patients with differential disease prognosis. EPSA can be applied to many different types of datasets in spite of different platforms, different experimental designs, and different species. Applying this method can yield new insights into human disease progression.

CONCLUSION

EPSA enables the use of publicly available data for an entirely new, translational purpose to enable the identification of potential pathways of dysregulation in human disease, as well as potential leads for therapeutic molecular targets.