Functions of septin cytoskeletal polymers in tumorigenesis are still poorly defined. Their role in the regulation of cytokinesis and cell migration were proposed to contribute to cancer associated ...aneuploidy and metastasis. Overexpression of Septin 9 (Sept9) promotes migration of cancer cell lines. SEPT9 mRNA and protein expression is increased in breast tumors compared to normal and peritumoral tissues and amplification of SEPT9 gene was positively correlated with breast tumor progression. However, the existence of multiple isoforms of Sept9 is a confounding factor in the analysis of Sept9 functions. In the present study, we analyze the protein expression of Sept9_i2, an uncharacterized isoform, in breast cancer cell lines and tumors and describe its specific impact on cancer cell migration and Sept9 cytoskeletal distribution. Collectively, our results showed that, contrary to Sept9_i1, Sept9_i2 did not support cancer cell migration, and induced a loss of subnuclear actin filaments. These effects were dependent on Sept9_i2 specific N-terminal sequence. Sept9_i2 was strongly down-regulated in breast tumors compared to normal mammary tissues. Thus our data indicate that Sept9_i2 is a negative regulator of breast tumorigenesis. We propose that Sept9 tumorigenic properties depend on the balance between Sept9_i1 and Sept9_i2 expression levels.
Magnesium silicide is a very promising thermoelectric material for applications in the temperature range of 500–800 K, and is of particular interest for large-scale applications because its ...constituents are non-toxic, inexpensive and very abundant in the Earth’s crust. Although the hot extrusion (HE) method to compact powders has long been considered for thermoelectric applications because it lends itself easily to large-scale industrial applications, advances to obtain Mg
2
Si by HE are still difficult to implement. We present the transformations undergone by Mg
2
Si powders during the nascent HE as well as the modifications of the structural, thermal and electronic properties of the compacted solid. MoS
2
particles (2 at.%) are added to the starting Mg
2
Si:Sb (0.5 at.%) powders which play the role of solid lubricant during this process at 873 K. Samples are extracted from different areas of the die along the extrusion direction and separately characterized, describing the transformations of the material through different stages of the nascent extrusion. X-ray diffraction reveals the expected structure for all samples without any significant texturing. The increase in grain size along the HE direction towards the exit has been determined from analysis of scanning electron microscopy observations. The thermoelectric properties have been characterized using the Harman method between 300 K and 700 K, giving Seebeck coefficients which vary between − 200
μ
V K
−1
and − 215
μ
V K
−1
at 700 K. The thermal (
λ
) and electrical (
σ
) conductivity decrease as the sample progresses in the extrusion process, and in the case of
λ
can be accounted for by the increase of sample porosity. The highest figure-of-merit
ZT
is to be found for the sample extracted from the exit of the die. It increases with temperature reaching a maximum value of 0.32 at 700 K, the highest temperature we could attain experimentally.
Purpose Interstitial cystitis is a chronic inflammatory disease of the bladder and luminal nitric oxide has been shown to be increased in the bladder in patients with interstitial cystitis. We ...analyzed endogenous nitric oxide formation and inducible nitric oxide synthase gene expression in the bladder of patients with interstitial cystitis to obtain further knowledge of the localization of inducible nitric oxide synthase in the bladder mucosa. Materials and Methods Six patients with interstitial cystitis and 8 controls were studied. In these 2 groups endogenous nitric oxide formation was measured and inducible nitric oxide synthase expression in bladder biopsies was analyzed at the transcriptional and protein levels by real-time polymerase chain reaction and Western blot, respectively. Immunohistochemistry for inducible nitric oxide synthase was also performed. Results Patients with interstitial cystitis had higher inducible nitric oxide synthase mRNA expression and nitric oxide formation than controls (p <0.01 and <0.001, respectively). Inducible nitric oxide synthase protein expression was up-regulated in the interstitial cystitis group. Immunohistochemistry showed that inducible nitric oxide synthase was predominantly localized to the urothelium in patients with interstitial cystitis but inducible nitric oxide synthase-like immunoreactivity was also found in macrophages in the bladder mucosa. Conclusions The increased levels of endogenously formed nitric oxide in patients with interstitial cystitis correspond to increased inducible nitric oxide synthase mRNA expression and protein levels in these patients. Furthermore, inducible nitric oxide synthase was found to be localized to the urothelium but it was also found in macrophages in the bladder mucosa. Whether high levels of endogenously formed nitric oxide are a part of the pathogenesis in interstitial cystitis and whether it has a protective or damaging role remain to be elucidated.
This review explores various aspects of the interaction between microtubule targeting agents and tubulin, including binding site, affinity, and drug resistance. Starting with the basics of tubulin ...polymerization and microtubule targeting agent binding, we then highlight how the three-dimensional structures of drug-tubulin complexes obtained on stabilized tubulin are seeded by precise biological and biophysical data. New avenues opened by thermodynamics analysis, high throughput screening, and proteomics for the molecular pharmacology of these drugs are presented. The amount of data generated by biophysical, proteomic and cellular techniques shed more light onto the microtubule-tubulin equilibrium and tubulin-drug interaction. Combining these approaches provides new insight into the mechanism of action of known microtubule interacting agents and rapid in-depth characterization of next generation molecules targeting the interaction between microtubules and associated modulators of their dynamics. This will facilitate the design of improved and/or alternative chemotherapies targeting the microtubule cytoskeleton.
Aim
To compare the therapeutic effect of α2 and α4 integrin‐blocking antibodies to conventional inflammatory bowel disease drugs methotrexate, 5‐aminosalicylic acid and azathioprine in the dextran ...sulphate sodium mouse colitis model.
Methods
Colitis was induced in balb/c mice with 2.5–3.0% dextran sulphate sodium. Treatment was given daily for 7 days after the onset of colitis, by rectal installation. Clinical signs of disease were assessed daily using a disease activity index. After 19 days, all animals were killed and colon samples collected for histological grading and mRNA/protein analysis. All treatment groups were compared with an untreated control group and a treatment group receiving dextran sulphate sodium alone to monitor the potential degree of clinical remission.
Results
Treatment with anti‐α2 antibodies and methotrexate reduced the body weight loss. At the end of treatment, anti‐α2 antibodies reduced rectal bleeding, while methotrexate reduced the disease activity index score. Histological evaluation showed that anti‐α2 antibodies, methotrexate, 5‐aminosalicylic acid and azathioprine treatment reduced the acute inflammation; methotrexate was the only treatment with effect on the crypt score. Compared with the dextran sulphate sodium alone group, the methotrexate group showed down‐regulation of IL‐1β at the mRNA level, while the anti‐α2 antibody group displayed decreased protein expression of iNOS and IL‐1β.
Conclusions
Specific blocking of extravascular trafficking of leucocytes with α2‐antibodies could be a new beneficial drug target in inflammatory bowel disease.
Combined treatment with selenite and the spingosine kinase 1 inhibitor SK1-II induces cell death in liver cancer cells (Huh7) without affecting non-tumorigenic immortalized liver cells (MIHA).
High ...doses of selenite have been shown to induce cell death in acute myeloid leukemia and lung cancer cells. In this study, we combined selenite treatment with modulators of sphingolipid metabolism in the hepatocellular carcinoma cell line Huh7. Treatment with 20μM of selenite reduced the viability of Huh7 cells by half and increased the levels of long chain C14-, C16-, C18- and C18:1- ceramides by two-fold. Inhibition of neutral sphingomyelinase with 3-O-methylsphingosine significantly reduced the cytotoxic effect of selenite. In line with this result, selenite caused a 2.5-fold increase in the activity of neutral sphingomyelinase. The sphingosine kinase 1 (SK1) inhibitor 2-(p-hydroxyanilino)-4-(p-chlorophenyl)thiazole (SK1-II) sensitized the cells to the cytotoxic effects of selenite. Preincubation with 10μM of SK1-II prior to treatment with 10μM of selenite caused induction of apoptosis and gave rise to a 2.5-fold increase in C14-, C16-, C18- and C18:1- ceramides. Instead, 50μM of SK1-II combined with 10μM of selenite caused accumulation of cells in G1/S phases, but less apoptosis and accumulation of ceramides. The formation of reactive oxygen species (ROS) after treatment with 10μM of selenite was maximally enhanced by 1μM of SK1-II. Moreover, combined treatment with SK1-II and 10μM of selenite synergistically reduced the number of viable Huh7 cells, while the non-tumorigenic hepatocyte cell line MIHA remained unaffected by the same treatment. These results raise the possibility that a combination of selenite and SK1 inhibitors could be used to treat liver cancer cells, that are regarded as drug resistant, at doses that are non-toxic to normal liver cells.
Osteoarthritis (OA) is characterized by erosion of cartilage and formation of osteophytes. Since transforming growth factor beta (TGF-beta) is known to be involved in chondrogenesis and osteogenesis, ...we studied by immunochemistry the expression of TGF-beta isoform types 1, 2, and 3 and their receptor types I and II in slightly and strongly altered areas of human OA cartilage and in osteophytes.
Specimens were collected from femoral heads at the time of hip arthroplasty, selecting osteophytic regions and areas of slight or severe degradation according to the Mankin score. Cryostat sections were prepared and submitted to immunohistochemistry using appropriate antibodies to TGF-beta(1-3) and TGF-beta receptors I and II.
TGF-beta1 expression was shown to be depressed in strongly degraded cartilage, compared to normal and slightly altered areas. TGF-beta2 was barely detectable in all samples studied. In osteophytes, a marked overexpression of TGF-beta1 and -beta3 was observed. An important decrease in TGF-beta receptor II was found in fibrillated cartilage areas.
The three major isoforms of TGF-beta are expressed in human OA cartilage, albeit the TGF-beta2 level is very low. Their expression patterns and the ratio of receptors I and II varies according to the degree of OA severity. The decrease in TGF-beta1 production and marked downregulation of receptor II in fibrillated cartilage may lead to reduced chondrocyte responsiveness to TGF-beta and contribute to the irreversibility of the disease. Overexpression of TGF-beta1 and -beta3 in osteophytes suggests that the two isoforms are involved in the formation of these structures.
We studied the effects of polymorphisms in nine genes involved in DNA repair and detoxification on occurrence and type of
p53 mutation in 327 bladder cancer patients. The included polymorphisms are
...XPC(Lys939Gln)
, XPD(Lys751Gln)
, XPG(Asp1104His)
, XRCC1(Arg3999Gln)
, XRCC3(Thr241Met)
, NBS1(Glu185Gln)
, cyclin D1(Pro241Pro)
, MTHFR(Ala222Val and Glu429Ala) and
NQO1(Arg139Trp and Pro187Ser). We found increased risk for
p53 mutation among
cyclin D1 variant allele homozygotes (OR 2.4 CI 0.8–6.7). Among non-smokers, 75% (3/4) with
p53 mutation but only 12.5% (3/24) without
p53 mutations were
XRCC3 241Met homozygotes (
P=0.03). Among smokers, all
p53 transversions (3/3), but only 41.7% (5/12) of
p53 transitions were found among carriers of the
XPC 939Gln allele. Individuals carrying the
NQO1 187Ser allele showed increased risk for
p53 transversions (OR 4.7, CI 0.9–26.1). All (2/2)
NQO1 139Trp allele carriers but only 17.5% (7/40) of the Arg139 homozygotes had
p53 transversions. Our findings suggest that altered repair and detoxification due to genetic polymorphism may influence the occurrence of
p53 mutations in bladder cancer.
We analyzed the associations of the
NOS2
(CCTTT)n promoter polymorphism to lung cancer risk and tumor histology in smokers and non-smokers. We also investigated lung cancer long-term survival in ...relation to the polymorphism, smoking data, histology, age at diagnosis, and gender. One hundred eighty-five lung-cancer patients and 164 matched controls, where non-smokers were enriched among the lung cancer cases, were genotyped by fragment analysis and sequencing. Genotypes were combined with information on histology, patient smoking status, and cancer-specific death, using a 20-year follow-up. We divided the (CCTTT)n alleles into short (
n
≤ 10), intermediate (
n
= 11–12), and long (
n
≥ 13). Patients homozygous for short repeats had significantly increased risk of lung cancer (
p
= 0.030) compared to carriers of two long alleles (LL). Lack of long allele was associated with a significantly increased lung cancer risk overall (
p
= 0.011), especially among non-smokers (
p
= 0.001). A significantly higher lung cancer survival was seen in non-smokers compared to smokers (
p
= 0.046) and in low-dose smokers compared to high-dose smokers at the time of diagnosis (
p
= 0.028). Moreover, non-smoking patients with squamous cell carcinoma (
p
= 0.015) or adenocarcinoma (
p
= 0.024) showed a significantly lower survival compared to other lung carcinomas. Nitric oxide can induce proliferation as well as apoptosis depending on cellular context. Our results suggest that the (CCTTT)n
NOS2
microsatellite may influence the risk of developing lung cancer, especially in non-smokers, possibly by affecting intracellular nitric oxide levels. Our results also give additional information about the yet poorly understood etiological and prognostic differences between lung cancer in non-smokers and smokers.
Objective
To study the effects of the very high minerality Vichy Thermal Spring Water (VTSW) on human keratinocytes grown in vitro.
Methods
The effect of VTSW was monitored by full genome ...transcriptomic technology and immunofluorescence microscopy.
Results
In the presence of 50% VTSW, the expression of a number of skin homoeostasis‐related genes is increased, specifically with respect to dermal‐epidermal junction, epidermal cohesion and communication, keratinocyte proliferation–differentiation balance, antioxidant mechanisms and DNA repair.
Conclusion
This work suggests that VTSW could be considered as an ingredient of potential interest to address some of the deleterious effects of skin ageing exposome.
Résumé
Objectifs
Etudier les effets de l'eau de source thermale de Vichy à très forte minéralité (VTSW) sur des kératinocytes humains cultivés in vitro.
Méthodes
L'effet de VTSW a été suivie par analyse transcriptomique du génome entier et par microscopie d'immunofluorescence.
Résultats
En présence de 50 % VTSW, l'expression d'un certain nombre de gènes liés à l'homéostasie de la peau est augmentée, notamment en ce qui concerne la jonction dermo‐épidermique, la cohésion et la communication épidermique, l’équilibre prolifération‐différenciation des kératinocytes, les mécanismes anti‐oxydants et de réparation de l'ADN.
Conclusion
Cette étude suggère que VTSW pourrait être considérée comme un ingrédient d'intérêt potentiel pour répondre à certains des effets délétères de l'exposome sur le vieillissement de la peau.
In the presence of 50% VTSW, the expression of a number of skin homeostasis related genes is increased, specifically with respect to dermal‐epidermal junction, epidermal cohesion and communication, keratinocyte proliferation‐differentiation balance, antioxidant mechanisms and DNA repair. The figure represents the dose‐effect of VTSW on TGM‐1, CK‐10 and FLG expression in HuKHN.
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