Inhibition of p38 by vitamin D reduces
interleukin-6 production in normal prostate cells via mitogen-activated
protein kinase phosphatase
5: implications for prostate cancer prevention by vitamin D.
Nonn L, Peng L, Feldman
D, Peehl DM.
Department of Urology, Stanford University School
of Medicine, Stanford, California 94305-5118, USA.
Although numerous studies have implicated vitamin D in preventing prostate
cancer, the underlying mechanism(s) remains unclear. Using normal human prostatic epithelial cells, we examined the role of mitogen-activated protein kinase
phosphatase 5 (MKP5) in mediating cancer
preventive activities of vitamin D. Up-regulation of MKP5 mRNA by
1,25-dihydroxyvitamin-D3 (1,25D) was dependent on the vitamin D receptor.
We also identified a putative positive vitamin D response element within
the MKP5 promoter that associated with the vitamin D receptor following
1,25D treatment. MKP5 dephosphorylates/inactivates
the stress-activated protein kinase p38.
Treatment of prostate cells with 1,25D inhibited p38 phosphorylation,
and MKP5 small interfering RNA blocked this effect. Activation of p38 and
downstream production of interleukin 6 (IL-6) are proinflammatory.
Inflammation and IL-6 overexpression have been
implicated in the initiation and progression of prostate cancer. 1,25D
pretreatment inhibited both UV- and tumor necrosis factor alpha-stimulated
IL-6 production in normal cells via p38 inhibition. Consistent with
inhibition of p38, 1,25D decreased UV-stimulated IL-6 mRNA stabilization.
The ability of 1,25D to up-regulate MKP5 was maintained in primary prostatic adenocarcinoma
cells but was absent in metastases-derived prostate cancer cell lines. The
inability of 1,25D to regulate MKP5 in the metastasis-derived cancer cells
suggests there may be selective pressure to eliminate key tumor suppressor
functions of vitamin D during cancer progression. These studies reveal MKP5
as a mediator of p38 inactivation and decreased IL-6 expression by 1,25D in
primary prostatic cultures of normal and adenocarcinoma cells, implicating decreased prostatic inflammation as a potential mechanism for
prostate cancer prevention by 1,25D.
Regulation of IL-1 family cytokines
IL-1alpha, IL-1 receptor antagonist, and IL-18 by 1,25-dihydroxyvitamin
D3 in primary keratinocytes.
Kong
J, Grando SA, Li
YC.
Department of Medicine, University of Chicago,
5841 South Maryland Avenue, Chicago, IL 60637, USA.
IL-1 family cytokines are key mediators of inflammatory response. Excessive
production of these cytokines by keratinocytes
has been implicated in inflammatory and hyperproliferative
skin diseases. Given the immunosuppressive role of 1,25-dihydroxyvitamin
D(3) (1,25(OH)(2)D(3)) and its clinical application in treatment of
psoriasis, we investigated the effect of 1,25(OH)(2)D(3) on the expression
of IL-1alpha, intracellular IL-1 receptor antagonist (icIL-1Ra), and IL-18
in mouse primary keratinocytes. Treatment of keratinocytes with 1,25(OH)(2)D(3)
increased the expression of IL-1alpha and icIL-1Ra and decreased the
expression of IL-18 in dose- and time-dependent manners. The magnitude of
icIL-1Ra induction was much greater than that of IL-1alpha so that the
ratio of icIL-1Ra to IL-1alpha was markedly increased, leading to
repression of IL-1 activity. The regulation of these three cytokines by
1,25(OH)(2)D(3) was mediated by vitamin D receptor (VDR), as
1,25(OH)(2)D(3) had no effect in VDR(-/-) keratinocytes,
whereas the effect was restored in cells derived from VDR(-/-) mice
expressing human VDR. 1,25(OH)(2)D(3) appeared to
use different mechanisms to regulate the biosynthesis of IL-1alpha and
icIL-1Ra: it increased IL-1alpha mRNA stability whereas it enhanced
icIL-1Ra gene transcription. The basal IL-18 expression and activity were
much higher in VDR(-/-) keratinocytes
and skin, underscoring the importance of the repressive role of vitamin D
in IL-18 production. Similar regulation of these cytokines was also seen in
primary human keratinocytes. Collectively, these
results suggest that vitamin D modulates cutaneous
inflammatory reactions, at least in part, by increasing the IL-1Ra to
IL-1alpha ratio and suppressing IL-18 synthesis in keratinocytes.
PMID: 16517748 [PubMed - indexed for MEDLINE]
Increased NF-{kappa}B Activity in
Fibroblasts Lacking the Vitamin D Receptor.
Sun
J, Kong
J, Duan Y, Szeto FL, Liao A, Madara JL, Li
YC.
Department of Pathology, University of Chicago,
Chicago, IL, USA.
1,25-Dihydroxyvitamin D [1,25(OH)2D3] is known to
have anti-inflammatory activity; however, the molecular mechanism remains
poorly defined. Here we show that the nuclear vitamin D receptor (VDR) is
directly involved in the regulation of NF-kappaB
activation, a pathway essential for inflammatory response. In mouse
embryonic fibroblasts (MEFs) derived from
VDR(-/-) mice, the basal level of IkappaBalpha
protein was markedly decreased compared to VDR(+/-) MEFs;
however, degradation of IkappaBalpha and its phosphorylation in response to TNFalpha
treatment or Salmonella infection were not altered in VDR(-/-) cells,
neither were the levels of IKKalpha and IKKbeta proteins. Consistent with IkappaBalpha
reduction, p65 accumulation in the nucleus was markedly increased in unstimulated VDR(-/-) cells.
In addition, the physical interaction between VDR and p65 was absent in VDR(-/-) MEFs, which may free
p65 and increase its activity. Consequently, these alterations combined led
to a marked increase in nuclear p65 DNA binding and NF-kappaB
transcriptional activity; consistently, induction of IL-6 by TNFalpha or IL-1beta was much more robust in VDR(-/-)
than in VDR(+/-) cells, indicating that VDR(-/-) cells are more susceptible
to inflammatory stimulation. Therefore, cells lacking VDR appear to be more
pro-inflammatory due to the intrinsic high NF-kappaB
activity. The reduction of IkappaBalpha in VDR(-/-) MEFs may be partially
explained by the lack of VDR-mediated stabilization of IkappaBalpha
by 1,25(OH)2D3. This is supported by the observation that IkappaBalpha degradation induced by TNFalpha
was inhibited by 1,25(OH)2D3 in VDR(+/-) cells,
but not in VDR(-/-) cells. Taken together, these data suggest that VDR
plays an inhibitory role in the regulation of NF-kappaB
activation.
PMID: 16507601 [PubMed - as supplied by
publisher]
PMID: 16618780 [PubMed - in process]
Association between
vitamin D receptor, CCR5, TNF-alpha and TNF-beta gene polymorphisms and HBV
infection and severity of liver disease.
Suneetha PV, Sarin SK, Goyal A, Kumar
GT, Shukla DK, Hissar S.
Department of Gastroenterology, GB Pant Hospital, New Delhi-2, India.
BACKGROUND/AIMS: 1,25-dihydroxyvitamin-D is
involved in immunomodulation. Expression of
vitamin-D receptors in hepatocytes suggests its
role in hepatocellular injury. We studied the
association of single nucleotide polymorphisms in genes involved in immunoregulatory functions of vitamin-D with
susceptibility, severity and persistence of HBV infection. METHODS: Five
polymorphisms in VDR, CCR5, TNF-alpha and TNF-beta were studied in 214
chronic hepatitis B patients and 408 controls. Clinical parameters were
compared between mild or severe liver disease patients. RESULTS: The
frequency of heterozygosity of CCR5Delta32 was
higher in chronic hepatitis B patients than controls (4.2 vs 0.73%, P=0.005). Frequency of VDR Apa1 a/a and
TNF-beta A/A was higher in severe compared with mild liver disease based on
HAI (19.3 vs 5.4%, P=0.003 and 18.1 vs 3.8%, P=0.001, respectively) and fibrosis score
(23.7 vs 3.6%, P<0.001 and 18.1 vs 4.4%, P=0.002, respectively). The frequency of VDR
a/a allele was also higher in patients with higher HBV DNA (11 vs 2.6%, P=0.002). Apa1 and Taq1 markers in VDR are in
linkage-disequilibrium and 'at'haplotype is
associated with severe liver disease. CONCLUSIONS: CCR5Delta32 heterozygosity was associated with susceptibility and
VDR a/a, TNF-beta A/A with severity of HBV-related liver disease and VDR
a/a allele with higher viral load. These results affirm an important role
of immunogenetic factors in the outcome of
chronic HBV infection.
PMID: 16545485 [PubMed - in process]
Cellular recognition of
herpes simplex virus infection and virus-induced cytokine production.
Melchjorsen
J.
Institute of Medical
Microbiology and
Immunology, The Bartholin Building, University of Aarhus, DK-8000 Arhus C.
jesper@microbiology.au.dk.
The aim of the PhD dissertation was i) to
determine the cytokine expression profile after herpes simplex virus (HSV)
infection, ii) describe cellular mechanisms of viral recognition, and iii)
identify viral proteins that inhibit or enhance cytokine production. The
dissertation includes five papers published and two manuscripts intended
for publication. HSV is a very common virus that clinically may manifest in
gingivostomatitis, herpes labialis,
keratitis, encephalitis, and genital herpes.
Normally the infection is self-limiting but in immuno-compromised
individuals, such as newborn babies, transplantation patients, and AIDS
patients the virus may spread throughout the body and result in
encephalitis, which is associated with high mortality and morbidity. i) The PhD study showed that HSV infection in dendritic cells and macrophages induces a number of
well known proinflammatory cytokines, chemokines, and interferons,
including the recently discovered type III interferons
IL-28 and IL-29. The study also presents the first evidence that IL-29 has
potential antiviral activity against HSV in human cells. Furthermore,
selective production of the chemokine RANTES was
seen in murine macrophages. ii) A group of
recognition receptors, termed Toll-like receptors (TLRs),
were investigated, and it was found that HSV infection was recognised through both TLR-dependent and
TLR-independent mechanisms. Downstream of recognition, HSV-induced
activation of the transcription factors IRF3 and NF-kappa-B was essential
for chemokine and interferon expression.
Furthermore, the kinases IKK-beta, TAK1, MEKK1,
and PKR also play important roles for the virus-induced cytokine
expression. iii) HSV evades the antiviral cytokine response through the
viral protein infected cell protein (ICP) 27. Infection of macrophage cell
cultures with ICP27-defective virus resulted in enhanced production of
antiviral cytokines and an enhanced activation of NF-kappa-B and IRF3. However,
the study also showed that virus replication is essential for cytokine
expression and that viral ICP0 positively affects the expression of
cytokines, such as the chemokine RANTES. In
conclusion, viral gene products both enhance and restrict cytokine production.
The project contributes with new knowledge on the progress of virus
infections and may eventually contribute to better design of treatments and
vaccines.
PMID: 16442008 [PubMed - in process]
IL-2 increased RANTES production and CD25
expression in cultured PBMCs only from
antiretroviral treated HIV-1+ patients with detectable viral loads.
Lozano
JM, Kindelan JM, Cabello A, Gonzalez
R, Solana
R, Pena
J.
Department of Immunology, Hospital "Reina
Sofia", University of Cordoba, Spain; Department of Virology, Pasteur
Institute of Paris, France.
In order to better understand the possible beneficial effects of intermittent
IL-2 treatment as complement of antiretroviral therapy in HIV-1+ patients,
we have measured the levels of RANTES in the supernatants and the CD25
expression in cultured PBMCs obtained from HIV-1+
individuals in presence of IL-2. The results showed a significant increases
in RANTES production and in the expression of CD25+ in the cultures with
IL-2 of PBMC obtained from HIV-1+ patients with a detectable viral load in
comparison with both, HIV-1+ patients with no detectable viral loads and
with healthy individuals. These results suggest that therapeutic IL-2
administered in addition to highly active anti-retroviral therapy (HAART)
may contribute to increase the effect of this therapy by rising both RANTES
production and CD25 expression only in HIV-1+ patients with detectable
viral loads.
PMID: 16644491 [PubMed - in process]
Tumor-derived CD4(+)CD25
(+) regulatory T cell suppression of dendritic
cell function involves TGF-beta and IL-10.
Larmonier
N, Marron
M, Zeng
Y, Cantrell
J, Romanoski
A, Sepassi
M, Thompson
S, Chen
X, Andreansky
S, Katsanis
E.
Department of Pediatrics, Steele Children's Research Center, University of
Arizona, 1501 N. Campbell Ave., P.O. Box 245073, Tucson, AZ, 85724-5073,
USA, katsanis@peds.arizona.edu.
CD4(+)CD25(+) regulatory T cells have been characterized as a critical
population of immunosuppressive cells. They play a crucial role in cancer
progression by inhibiting the effector function
of CD4(+) or CD8(+) T lymphocytes. However,
whether regulatory T lymphocytes that expand during tumor progression can
modulate dendritic cell function is unclear. To
address this issue, we have evaluated the inhibitory potential of CD4(+)CD25(+) regulatory T cells from mice bearing a
BCR-ABL(+) leukemia on bone marrow-derived dendritic
cells. We present data demonstrating that CD4(+)CD25(+)FoxP3(+)
regulatory T cells from tumor-bearing animals impede dendritic
cell function by down-regulating the activation of the transcription factor
NF-kappaB. The expression of the co-stimulatory
molecules CD80, CD86 and CD40, the production of TNF-alpha, IL-12, and
CCL5/RANTES by the suppressed DC is strongly down-regulated. The
suppression mechanism requires TGF-beta and IL-10 and is associated with
induction of the Smad signaling pathway and
activation of the STAT3 transcription factor.
PMID: 16612596 [PubMed - as supplied by
publisher]
Rat peritoneal mast cells release regulated
upon activation normal T cell expressed and secreted (RANTES) after
TNF-alpha activation.
Kempuraj D, Petrarca C, Frydas S, Riccioni G, Conti
P, Tete S, Vecchiet J.
Pharmacology Department, Medical School, Tufts University, Boston, MA, USA.
Chemokines are a family consisting of at least
ten distinct novel 8-10 kD
cytokines. The cysteine-cysteine (C-C) chemokines are chemoattractant
and activators for monocytes, T cells and mast
cells. RANTES is the prototype of the C-C chemokine
subfamily, purified from different sources with chemoattractant
and activator properties. In this study we found that supernatants derived
from TNF-alpha (scalar concentrations)-activated rat peritoneal mast cell
cultures (5 x 10(5)/mL), incubated overnight,
produced high levels of RANTES. This data describes an additional mode of
generation of RANTES. Moreover, RANTES mRNA was not significantly produced
in untreated cells, while it was dramatically increased by calcium ionophore A23187, LPS and TNF-alpha compared with the
controls. These results underscore the importance of the presence of mast
cells for the production of RANTES in the inflammatory process and
contribute to an understanding of the mechanism by which RANTES profoundly
affects inflammatory responses in vivo.
PMID: 16602627 [PubMed - in process]
Interleukin 5, IL6, IL12, IFN-gamma, RANTES and Fractalkine in human nasal polyps, turbinate mucosa and
serum.
Danielsen A, Tynning T, Brokstad KA, Olofsson J, Davidsson A.
Department of Otorhinolaryngology,
Axess Medical Hospital, Oslo, Norway.
Polyps are considered to develop as an end result of an inflammatory
process. Cytokines and chemokines in the
respiratory mucosa may be a key to polyp pathophysiology.
The main objective was to identify IL-5, IL-6, IL-12, RANTES, IFN-gamma and
Fractalkine in humans on the protein level in
nasal polyps and mucosa from the inferior turbinate (IT). Furthermore, the
cytokines and chemokines RANTES and Fractalkine were analyzed in plasma. Tissue homogenates
and plasma from 13 patients were analyzed by the ELISA technique. All the
patients had longstanding nasal/paranasal polyposis. Fractalkine was
detected in polyps and IT in two different patients. IL-5 was expressed in
polyps and IT. IL-6 was expressed in all patients with a higher level in
polyps than IT. IL-12 was present in plasma, polyps and IT, though at an
increased level in polyps. RANTES was present at a higher level in plasma
than in polyps and IT. IFN-gamma was detectable in polyps and IT. Fractalkine is detected in nasal polyps, which is a new
observation. The overall results indicate a mixed T(H)1/T(H)2
cytokine profile in nasal polyps. RANTES and IL-12 are strongly present in
plasma, suggesting an ongoing inflammatory "drive". IL-6 and
IL-12 are up-regulated in polyps versus the IT. Up-regulation of IL-6 may
be explained by increased fibroblast activity dependant on an ongoing local
inflammation possibly initiated by an infection. IL-5, RANTES and IFN-gamma
are equally represented in polyps and IT, indicating equilibrium between
the nasal polyps and surrounding tissue, and that an up-regulation of
cytokines in the polyp indicates a potential for polyp growth.
Relation of p53, Bcl-2,
Ki-67 and E-cadherin expressions in early
invasive breast cancers with comedonecrosis (CN)
as an accelerated apoptosis.
Hosaka
N, Ryu
T, Cui W, Li Q, Nishida A,
Miyake T, Inaba
M, Ikehara
S.
Kansai Medical University, Japan.
AIMS: To study the relationship between comedonecrosis
(CN) formation and morphology, apoptosis, and p53, Bcl-2, Ki-67 index and
E-cadherin expression in early invasive breast
cancer. Experimental design: We first divided early invasive breast cancers
into two groups according to the presence (CN+ tumors) or absence (CN-
tumors) of CN. Next, we examined the histological grade, apoptosis, and
expressions of E-cadherin, Ki-67, p53 and Bcl-2
in the cancer area as well as in normal ducts (ND) from the specimen.
RESULTS: CN+ tumors showed less tubule and gland formation than CN- tumors,
although the histological grade was no different between the groups. Cells
during early CN undergo apoptosis and subsequent necrosis. Whereas p53 was
higher in CN+ tumors than in CN- tumors and ND, Bcl-2 was lower in CN+
tumors than in CN- tumors and ND. Ki-67 in both tumors were
higher than in ND, but there was no difference between the tumors. E-cadherin in CN+ tumors was slightly higher than in CN-
tumors, but lower than in ND. The level of CN was positively correlated
with p53, but inversely correlated with Bcl-2 in all tumors, and p53and
Bcl-2 were inversely correlated with each other.
Furthermore, CN and p53 were correlated with Ki-67 in CN+ tumors, and Bcl-2
was correlated with Ki-67 in CN- tumors. CONCLUSION: CN may be actively
regulated via an apoptotic procedure in massive cancers for their survival
and progression, and the above proteins may be involved cooperatively in
this process. CN+ and CN- tumors may have opposite proliferative
systems under the p53-Bcl-2 pathway.
PMID: 16473926 [PubMed - as supplied by publisher]
Estrogen receptor-alpha binds p53 tumor
suppressor protein directly and represses its function.
Liu W, Konduri
SD, Bansal
S, Nayak
BK, Rajasekaran
SA, Karuppayil
SM, Rajasekaran
AK, Das
GM.
Pharmacology & Therapeutics, Roswell Park Cancer Institute, Buffalo, NY
14263.
Estrogen receptor-alpha (ERalpha) promotes cell
proliferation of breast cancer cells whereas tumor suppressor protein p53
impedes proliferation of cells with genomic damage. Whether there is a
direct link between these two antagonistic pathways has remained unclear.
Here we report that ERalpha binds directly to p53
and negatively regulates its function. The activation function-2 (AF-2)
domain of ERalpha and the C-terminal regulatory
domain of p53 are necessary for the interaction. Knocking down p53 and ERalpha by small interfering RNA (siRNA)
elicits opposite effects on p53-target gene expression and cell cycle
progression. Remarkably, ionizing radiation that causes genomic damage
disrupts the interaction between ERalpha and p53.
Ionizing radiation together with ERa knock down
results in an additive effect on transcription of endogenous p53-target
gene p21 (CDKN1) in human breast cancer cells. Our findings reveal a novel
mechanism for regulating p53 and suggest that suppressing p53 function is
an important component in the pro-proliferative
role of ERalpha.
PMID: 16469747 [PubMed - as supplied by
publisher]
Relation of p53, Bcl-2, Ki-67 and E-cadherin expressions in early invasive breast cancers
with comedonecrosis (CN) as an accelerated
apoptosis.
Hosaka
N, Ryu
T, Cui W, Li Q, Nishida A,
Miyake T, Inaba
M, Ikehara
S.
Kansai Medical University, Japan.
AIMS: To study the relationship between comedonecrosis
(CN) formation and morphology, apoptosis, and p53, Bcl-2, Ki-67 index and
E-cadherin expression in early invasive breast
cancer. Experimental design: We first divided early invasive breast cancers
into two groups according to the presence (CN+ tumors) or absence (CN-
tumors) of CN. Next, we examined the histological grade, apoptosis, and
expressions of E-cadherin, Ki-67, p53 and Bcl-2
in the cancer area as well as in normal ducts (ND) from the specimen.
RESULTS: CN+ tumors showed less tubule and gland formation than CN- tumors,
although the histological grade was no different between the groups. Cells
during early CN undergo apoptosis and subsequent necrosis. Whereas p53 was
higher in CN+ tumors than in CN- tumors and ND, Bcl-2 was lower in CN+
tumors than in CN- tumors and ND. Ki-67 in both tumors were
higher than in ND, but there was no difference between the tumors. E-cadherin in CN+ tumors was slightly higher than in CN-
tumors, but lower than in ND. The level of CN was positively correlated
with p53, but inversely correlated with Bcl-2 in all tumors, and p53and
Bcl-2 were inversely correlated with each other.
Furthermore, CN and p53 were correlated with Ki-67 in CN+ tumors, and Bcl-2
was correlated with Ki-67 in CN- tumors. CONCLUSION: CN may be actively
regulated via an apoptotic procedure in massive cancers for their survival
and progression, and the above proteins may be involved cooperatively in
this process. CN+ and CN- tumors may have opposite proliferative
systems under the p53-Bcl-2 pathway.
PMID: 16473926 [PubMed - as supplied by
publisher]
Prostate
