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.
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.
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.
Nuclear p53 expression is a sensitive parameter for the detection of ultraviolet (UV)‐induced skin damage, and it has been used as an endpoint to evaluate the effectiveness of sunscreens. In this ...study, we compared the protection provided by two sunscreens having identical sun protection factors (SPF) but different UVA protection factors (UVA‐PF) measured by the persistent pigment darkening method (PPD). The SPF of the sunscreens was 7 and the UVA‐PF were respectively 7 and 3. Nuclear p53 protein was quantified in human skin biopsies treated with sunscreens and exposed 8 times to 5 MED of solar simulated radiation (SSR). The results showed that both sunscreens offered only partial protection against the increased expression of nuclear p53 protein induced by repetitive SSR exposures. However, a significantly lower level of p53‐positive cells was found in areas protected with the sunscreen having the higher UVA‐PF compared to the other sunscreen protected areas. In order to verify whether the difference in efficacy of these products was due to the difference in UVA absorption capacity, we quantified epidermal p53 protein accumulation after 8 exposures to either UVA (320–400 nm) or UVA1 (340–400 nm). We showed that as with SSR, repetitive exposures to 12.5 and 25 J/cm2 of UVA or UVA1 induced a significant increase in p53‐positive cells in the human epidermis. These results confirmed that SPF determined on the basis of an acute erythemal reaction does not predict the level of protection against cumulative damage. They also showed that the protection provided by two sunscreens with different UVA protection factors is different (based on nuclear p53 protein accumulation), and that the PPD method can distinguish varying levels of sunscreen efficacy against UVA‐induced cell damage.
The telomerase reverse transcriptase (TERT) promoter, an important element of telomerase expression, has emerged as a target of cancer-specific mutations. Originally described in melanoma, the ...mutations in TERT promoter have been shown to be common in certain other tumor types that include glioblastoma, hepatocellular carcinoma, and bladder cancer. To fully define the occurrence and effect of the TERT promoter mutations, we investigated tumors from a well-characterized series of 327 patients with urothelial cell carcinoma of bladder. The somatic mutations, mainly at positions −124 and −146 bp from ATG start site that create binding motifs for E-twenty six/ternary complex factors (Ets/TCF), affected 65.4% of the tumors, with even distribution across different stages and grades. Our data showed that a common polymorphism rs2853669, within a preexisting Ets2 binding site in the TERT promoter, acts as a modifier of the effect of the mutations on survival and tumor recurrence. The patients with the mutations showed poor survival in the absence hazard ratio (HR) 2.19, 95% confidence interval (CI) 1.02–4.70 but not in the presence (HR 0.42, 95% CI 0.18–1.01) of the variant allele of the polymorphism. The mutations in the absence of the variant allele were highly associated with the disease recurrence in patients with Tis, Ta, and T1 tumors (HR 1.85, 95% CI 1.11–3.08). The TERT promoter mutations are the most common somatic lesions in bladder cancer with clinical implications. The association of the mutations with patient survival and disease recurrence, subject to modification by a common polymorphism, can be a unique putative marker with individualized prognostic potential.
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