Induction of chromosomal instability in colonic cells by the human polyomavirus JC virus

Most colorectal cancers display chromosomal instability, which is characterized by gross chromosomal rearrangements, loss of heterozygosity and aneuploidy. We have previously demonstrated a link between JC virus strains Mad-1 and Delta98 and colorectal cancer. Others have also associated the virus to the induction of colon cancer and aneuploid brain tumors by producing a highly tumorigenic protein named T antigen (TAg), which binds to beta-catenin and inactivates key proteins such as p53. The aim is to demonstrate that JC virus is capable of inducing chromosomal instability in colonic cells. We used the human colon cancer cell line RKO as a model. The cell line has wild-type p53, wild-type beta-catenin and APC and is diploid. Neuroblastoma JCI cells, which are infected with the virus, VA13 fibroblasts, which are transformed by the SV40 TAg, were used as positive controls. HCT116, which has mutated beta-catenin, and SW480, which is a model of CIN, were also used as controls. The genomes of the Mad-1 and Delta98 strains were transfected into cells. As negative controls we used pUC or no plasmids. Cells were collected at 0, 7, 14, and 21 days after transfection. PCR was used for the detection of TAg and the regulatory region DNA sequences at different time frames and Southern blot of whole genomic extracts for viral DNA integration into the host genome. Immunofluorescence and Western blot were performed for TAg, viral capsid proteins, and nuclear beta-catenin expressions, whereas coimmunoprecipitation was used to detect protein interactions. Karyotype analysis and electron microscopy were performed to seek chromosomal instability and cell abnormalities, respectively. Retention of viral sequences was observed for Mad-1- and Delta98-transfected RKO cells at all time frames with PCR only, whereas Southern blot analysis showed nonintegrated sequences at T7 alone. TAg and capsid protein expressions, as well as increased p53 and nuclear beta-catenin, were observed between T0 and T7 for Mad-1 and Delta98 alone. Also, interaction between TAg and both p53 and beta-catenin was also observed between T0 and T7. Chromosomal instability, characterized by chromosomal breakage, dicentric chromosomes, and increasing ploidy, was observed at all time frames for Mad-1 and Delta98, as well as cell abnormalities. In conclusion, we demonstrate that JC virus Mad-1 and Delta98 are able to induce chromosomal instability in colonic cells with a hit and run mechanism that involves an early interaction with beta-catenin and p53.     

Effects of a mitogen-activated protein kinase inhibitor on allergic airways inflammation in the rat studied by magnetic resonance imaging

We recently described a new model to study non-invasively with magnetic resonance imaging (MRI) the effects of compounds to prevent and/or resolve airway inflammation induced by ovalbumin in the lungs of actively sensitised rats. We report here the effects of 4-(4-fluorophenyl)-2-(1-methylpiperidin-4-yl)-5-(2-(1-(S)-phenylethyl)amino-4-pyridinyl)thiazole fumarate (Compound 1), which exhibits inhibitory activity against p38alpha and p38beta2 and residual activity on c-Jun amino-terminal kinase (JNK)2 mitogen-activated protein (MAP) kinases, on the oedematous signals detected by MRI and generated by antigen challenge in the lungs of sensitized rats. Compound 1 (10 mg kg(-1)) given orally 1 h prior to allergen challenge significantly reduced the oedematous signal measured at 24 h. Similar effects were seen with a synthetic corticosteroid, mometasone furoate (0.3 mg kg(-1)), given intratracheally 3 h prior to challenge. For both compounds, inhibition of the oedematous signal was accompanied by reductions in the inflammatory parameters in the bronchoalveolar lavage fluid measured 24 h after challenge with ovalbumin. Compound 1 (10 mg kg(-1)) administered 24 h after challenge with ovalbumin did not change the rate of resolution of the signal detected by MRI in the lungs. In contrast, mometasone furoate (0.3 mg kg(-1)) significantly increased resolution of these signals, which was evident 3 h after drug administration and maintained to 48 h post challenge. Collectively, our data suggest that the p38 MAP kinase inhibitor Compound 1 shows a different profile than glucocorticosteroids since its ability to resolve existing inflammation is limited.     

A novel atypical retinoid endowed with proapoptotic and antitumor activity

The novel atypical retinoid E-3-(4'-hydroxy-3'-adamantylbiphenyl-4-yl)acrylic acid (ST1926, 4) exhibited a potent antiproliferative activity on a large panel of human tumor cells. Despite almost complete loss of ability to activate RARs, the compound was an effective apoptosis inducer and surprisingly produced DNA damage, that likely contributes to the proapoptotic activity. Following oral administration, 4 was well tolerated and caused tumor growth inhibition in the ovarian carcinoma, A2780/DX, and in the human melanoma, MeWo, growing in nude mice, thus supporting the therapeutic interest of the novel agent.     

Antibacterial new clerodane diterpenes from the surface of Haplopappus foliosus

A biologically monitored fractionation of the resinous exudate extract of Haplopappus foliosus DC. is reported. Purification of the two active fractions yielded 2-alpha-hydroxy- cis-cleroda-3,13(Z),8(17)-trien-15-oic acid (1) and 2-alpha-acetoxy- cis-cleroda-3,13(Z),8(17)-trien-15-oic acid (2), two new clerodane diterpenes.     

Comparing the efficacy and safety of fixed versus weight-based dosing of epoetin alpha in anemic cancer patients receiving platinum-based chemotherapy

Fixed dosing is potentially more convenient than weight-based dosing for both patients and physicians. Therefore, this open-label, randomized (1:1), multicenter study was conducted to compare the effectiveness, safety, and quality-of-life benefits of fixed vs. weight-based dosing of epoetin alpha in anemic cancer patients undergoing chemotherapy. Five hundred forty-six anemic patients undergoing platinum-based chemotherapy for solid malignancies were enrolled. Patients received epoetin alpha, either a fixed dose of 10,000 IU or a weight-based dose of 150 IU/kg, administered subcutaneously 3 times weekly for up to 12 weeks. Endpoints were transfusion requirements over days 29-84, change in hemoglobin (Hb) level from baseline, and change in quality-of-life (QOL) scores from baseline as measured using the Cancer Linear Analog Scale (CLAS). Five hundred and thirty-two patients received at least 1 dose of epoetin alpha, and 510 of these (255 in each treatment group) were considered evaluable for efficacy. At day 84, rates for freedom from transfusion were similar between the fixed-dose and the weight-based dose group (84% vs. 87%, respectively, p=0.32), as calculated by the lifetable method. These rates were also similar between patients in the 45-63 kg weight group receiving the fixed 10,000 IU dose or 7,000-9,000 IU on a per-weight basis (83% vs. 87%, respectively), and those in the 70-100 kg weight group receiving the fixed 10,000 IU dose or 11,000-15,000 IU on a per-weight basis (85% vs. 83%, respectively). Mean Hb increases from baseline to last observation were 2.10 g/dl [95% confidence intervals (CI95) 1.85-2.35] in the 10,000 IU group (from 9.64-11.74 g/dl) and 2.06 g/dl (CI95 1.82-2.30) in the 150 IU/kg group (from 9.70-11.76 g/dl). QOL results were similar for both groups and cumulative data have been reported. For 275 patients (in both groups combined) with CLAS QOL scores both at baseline and 29-98 days thereafter, the QOL index (average of scores for the 3 QOL parameters: energy level, ability to do daily activities and overall QOL) increased by 10.4 mm (CI95 7.5-13.2), from 46.2 mm at baseline to 56.6 mm at the final observation. QOL improvements were directly associated with Hb increases (p<0.001, multiple linear regression analysis) within all chemotherapy response classes. Epoetin alpha was well tolerated in both groups. Fixed (10,000 IU) and weight-based (150 IU/kg) dosing regimens of epoetin alpha demonstrated similar efficacy in maintaining freedom from transfusion, increasing Hb levels, and improving QOL in anemic cancer patients undergoing platinum-based chemotherapy. QOL improvements were directly associated with Hb increases. These findings support the use of a fixed-dose regimen of epoetin alpha, which may offer greater convenience for physicians and patients than weight-based dosing with this agent.     

Combination of DNA repair gene single nucleotide polymorphisms and increased levels of DNA adducts in a population-based study.

Inherited single nucleotide polymorphisms (SNPs) of DNA repair genes may contribute to variations in DNA repair capacity and susceptibility to cancer. We investigated the role of SNPs in three DNA repair genes (X-ray repair cross-complementing group 1-Arg399Gln, exon 10; X-ray repair cross-complementing group 3-Thr241Met, exon 7; and xeroderma pigmentosum-D-Lys751Gln, exon 23) and their combination, in modulating the levels of "bulky" DNA adducts in a population sample of 628 Italian healthy individuals belonging to the prospective European project "European Prospective Investigation into Cancer and Nutrition." DNA-adduct levels were measured as relative adduct level per 10(9) nucleotides by (32)P-post DNA labeling assay in WBCs from peripheral blood. Genotyping was performed by PCR-RFLP analysis or primer extension/denaturing high-performance liquid chromatography technique. We found a dose-response relationship between the number of at-risk alleles and levels of adducts (P = 0.0046). Individuals with at least three variant alleles had a statistically significant odds ratio (OR) for being in the highest tertile of adducts compared with those with undetectable adducts [three alleles, adjusted OR = 5.07, 95% confidence interval (CI) = 1.29-19.9; four alleles, adjusted OR = 5.03, 95% CI = 1.18-21.45; five alleles, adjusted OR = 7.65, 95% CI = 0.94-62.2]. Our study suggests that the combined effect of multiple variant alleles may be more important than the investigation of single SNP in modulating DNA repair capacity.     

Evaluation of oocyte maturity in patients undergoing ICSI and R-FSH treatment

BACKGROUND: This study compares embryo quality, fertilisation rate and pregnancy rates after ICSI related with the quality of oocytes achieved after r-FSH stimulation. METHODS: We evaluated 955 oocytes from patients following r-FSH and 643 oocytes from patients stimulated with ultrapure urinary FSH. The oocytes were divided into: a) normal oocytes; b) ooctyes with extra cytoplasmatic abnormalities (dark zona pellucida, wide perivitelline space); c) oocytes with cytoplasmatic abnormalities (dark cytoplasm, granular cytoplasm, retractile body), d) oocytes with shape abnormalities; e) oocytes with double abnormalities; f) oocytes with triple abnormalities. The embryos were divided into: A) even and homogeneous blastomeres without fragmentation; B) even and homogeneous blastomeres with <20% fragmentation; C) uneven and non-homogeneous blastomeres with 20-50% fragmentation; D) uneven and non homogeneous blastomere with >50% fragmentation. RESULTS: 40.9% of oocytes from patients treated with r-FSH have a normal morphology vs 35.2% of control groups (p<0.04). Abnormalities have a similar frequency in the two groups, except for the presence of three combined abnormalities (7.7 vs 5.4%; p<0.04). Fertilisation rate, cleavage rate, oocyte quality and pregnancy rate do not appear to be influenced by oocyte morphology and the type of FSH used for stimulation. CONCLUSIONS: The administration of r-FSH allows a large number of oocytes to be rescued, with a high incidence of normal morphology. The fertilisation rate and the quality of embryos obtained from oocytes with structural abnormalities are similar to those observed in morphologically normal oocytes. Even the probability of pregnancy is similar in the two groups.