Atopic dermatitis (AD) management in an Italian pediatric clinic

AIM

Atopic dermatitis (AD) is a common, chronic relapsing inflammatory skin disease characterized by dry skin and variable pruritus sometimes associated with allergic disease in other organs as asthma and rhinoconjunctivitis. AD affects deeply the Quality of Life, thus can be extremely disabling and may cause psychological problems for both affected children and their families.

METHODS

In order to investigate the estimated prevalence of the disease and the beliefs of the Italian pediatricians, a group of 437 Italian family pediatricians covering a population of almost 380000 children participated in a study based on a questionnaire of 38 items.

RESULTS

According to answers of the participants, the incidence of AD has been estimated around 10% of the population and food allergy is believed to be the trigger of the acute phase of the disease in infants. As a second opinion, dermatologists are consulted more frequently than allergologists.

CONCLUSION

The use of emollients is advised in general whilst topical corticosteroids treatment is prescribed only in selected cases; more than 50% of pediatricians do not prescribe topical calcineurin inhibitors.

An EZH2 polymorphism is associated with clinical outcome in metastatic colorectal cancer patients

BACKGROUND

Despite therapeutic innovations, metastatic colorectal cancer (mCRC) is still characterized by poor prognosis and few molecular markers predict the risk of progression. Polycomb group genes (PcGs) are epigenetic modifiers involved in tumor suppressor gene silencing. PcG member EZH2 mediates gene silencing through histone-H3 lysine-27 methylation. In colorectal cancer (CRC), EZH2 overexpression predicts shorter survival. Recently, four EZH2 single-nucleotide polymorphisms (SNPs) have been described. The present study was aimed at evaluating the correlation between EZH2 SNPs and outcome parameters in mCRC patients.

PATIENTS AND METHODS

DNA was extracted from blood samples of 110 mCRC patients treated with first-line 5-fluorouracil, folinic acid, irinotecan (FOLFIRI) and bevacizumab. Genotyping was carried out by real-time PCR. Genotype was used to predict objective response, progression-free survival (PFS) and overall survival (OS). EZH2 messenger RNA levels were evaluated on lymphocytes of a parallel cohort of 50 CRC patients.

RESULTS

One allelic variant (rs3757441 C/C versus C/T or T/T) was significantly associated with shorter PFS and OS (P < 0.01 and P < 0.05, respectively). At multivariate analysis, the same variant resulted an independent predictor of PFS and OS (P < 0.05). The C/C variant was associated with significantly higher EZH2 expression (P < 0.05).

CONCLUSION

An EZH2 SNP may be useful to predict clinical outcome in mCRC patients.

Pharmacodynamic and pharmacogenetic angiogenesis-related markers of first-line FOLFOXIRI plus bevacizumab schedule in metastatic colorectal cancer

Background:

The identification of molecular and genetic markers to predict or monitor the efficacy of bevacizumab (BV) represents a key issue in the treatment of metastatic colorectal cancer (mCRC).

Methods:

Plasma levels of vascular endothelial growth factor (VEGF), placental growth factor (PlGF), soluble VEGF receptor 2 (sVEGFR-2) and thrombospondin-1 (TSP-1) were assessed by ELISA assay at different time points in a cohort of 25 patients enroled in a phase II trial of GONO-FOLFOXIRI plus BV as first-line treatment of mCRC. VEGF: −2578A/C, −1498C/T, −1154A/G, −634C/G and 936C/T; and VEGFR-2: −604A/G, +1192C/T and +1719A/T, polymorphisms were assessed in a total of 54 patients.

Results:

Treatment with GONO-FOLFOXIRI plus BV determined a prolonged and significant reduction in plasma free, biologically active VEGF concentration. Interestingly, VEGF concentrations remained lower than at baseline also at the time of PD. Conversely, PlGF levels increased during the treatment if compared with baseline, suggesting a possible role in tumour resistance; moreover, sVEGFR-2 increased at the time of PD, as well as TSP-1. No association of assessed polymorphisms with outcome was found.

Conclusion:

Our study suggested the possible mechanisms of resistance to combined therapy in those patients with a progressive disease to be tested in ongoing phase III randomised studies.

Study of apoptosis induction and deoxycytidine kinase/cytidine deaminase modulation in the synergistic interaction of a novel ceramide analog and gemcitabine in pancreatic cancer cells

This study investigated the interaction between the novel ceramide analog AL6 and gemcitabine in MIA PaCa-2 and PANC-1 pancreatic cancer cell lines, harboring different polymorphic variants of the gemcitabine catabolism enzyme cytidine deaminase (CDA). AL6 dose-dependently inhibited cell growth, induced apoptosis and synergistically enhanced the cytotoxic activity of gemcitabine. Moreover, it triggered apoptosis, which was significantly enhanced by the combination, and increased the ratio between gene expression of the activating enzyme deoxycytidine kinase (dCK) and CDA, potentially favoring gemcitabine activity. In conclusion, AL6 displays synergistic cytotoxic activity, enhances apoptosis, and favorably modulates enzymes involved in gemcitabine metabolism, supporting future investigation of this combination in pancreatic cancer.

Correlation between cytidine deaminase genotype and gemcitabine deamination in blood samples

Cytidine deaminase (CDA) is the major enzyme of gemcitabine inactivation. The aim of this study was to determine whether the CDA Lys27Gln polymorphism influenced gemcitabine deamination in blood samples from 90 lung cancer patients. The polymorphism was studied with Taqman probes-based assay; CDA activity was evaluated by HPLC in cytoplasmic extracts from red blood cells. Mean enzymatic activity was significantly lower in patients carrying the CDA Lys27Lys than in patients with the Lys27Gln or Gln27Gln protein (P < 0.05). CDA genotyping may be useful in screening patients before gemcitabine treatment, in order to identify subjects with lower CDA activity and potentially better clinical outcomes after gemcitabine-based chemotherapy.

In vitro studies on gemcitabine combinations with other antiblastics

The use of gemcitabine in combination with chemotherapeutic agents, including cisplatin, pemetrexed and taxanes, is characterized by the enhancement of their anticancer activity. The analysis of the underlying pharmacodynamics has revealed that modulation of nucleotide pools, drug metabolism, and cellular DNA repair capability are the most common factors to explain the additive to synergistic interaction between gemcitabine and anticancer agents in several human cancers in vitro and in vivo.

In vitro antiangiogenic activity of selective somatostatin subtype-1 receptor agonists

BACKGROUND

Endothelial cells of human blood vessels (arteries and veins) show high levels of somatostatin subtype-1 receptor (sst(1)). The aim of the present study is to investigate the inhibitory effects of novel somatostatin analogs, highly selective for human sst(1), on in vitro angiogenesis and their modulation of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-2 (VEGFR-2) expression.

MATERIALS AND METHODS

Somatostatin analogs BIM-23745 and BIM-23926 were tested for their ability to prevent proliferation and migration of human endothelial HMEC-1 cells, to modulate VEGF and VEGFR-2 expression and to inhibit sprouting of microvessels from cultured human placental vessel explants in fibrin matrix for 28 days.

RESULTS

The somatostatin sst(1 )receptor-selective agonists, BIM-23745 and BIM-23926 showed a suppression of endothelial proliferation (e.g. 10(-6) M BIM-23475, 40.0 +/- 2.1% vs. 100% of controls; 10(-7) M BIM-23926, 55.3 +/- 3.3% vs. 100% of controls), migration (e.g. 10(-7) M BIM-23475, 35.0 +/- 1.56% vs. 100% of controls; 10(-7) M BIM-23926, 53.7 +/- 1.77% vs. 100% of controls) and microvessel sprouting (e.g. 10(-8) M BIM-23475, 42.8 +/- 5.6% vs. 100% of controls; 10(-7) M BIM-23926, 17.2 +/- 11.8% vs. 100% of controls). A small but significant percentage of cells exposed to BIM-23745 and BIM-23926 for 24 h and for 72 h presented typical apoptotic morphology. Moreover, both the analogs significantly inhibit VEGF and VEGFR-2 gene expression in endothelial cells grown for 144 h in a fibrin matrix and the VEGF secretion in conditioned media.

CONCLUSIONS

The inhibition of endothelial activities suggests potential therapeutic utility for administration of somatostatin sst(1 )receptor-selective agonists in the proliferative diseases involving angiogenesis.

Induction of gemcitabine (GCB)-related genes by pemetrexed (MTA): Assessment of the best time interval between MTA and GCB administration

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Background: Both MTA and GCB are active drugs in non-small cell lung cancer (NSCLC). Many molecular events induced by MTA support the synergic interaction between the two drugs and explain why the sequence MTA ? GCB is more active than GCB ? MTA. Of major interest, MTA induces the expression of deoxycytidine kinase (dCK), the rate-limiting enzyme of GCB activation, and of the human equilibrative nucleoside transporter-1 (hENT1), the key transporter for the intracellular penetration of GCB. Even if the optimal sequence is well established, no information on the best administration time between the two drugs is available. Methods: To evaluate if there is a reproducible timing of maximum dCK and hENT1 expression by MTA, we measured these targets in patients with advanced NSCLC after administration of MTA 500 mg/m2 q2wks. All patients were not pre-treated with MTA or GCB. Gene-expression was measured in normal lymphocytes by quantitative real-time PCR (qRT-PCR), at various interval (up to 48 hrs) at each of the first 3 chemotherapy cycles. Results: Between September and December 2006, 8 out of the 19 planned patients were enrolled in the present study. At the time of this analysis, dosages from 63 samples / 9 cycles of chemotherapy are available. In all treatment cycles, qRT-PCR analysis revealed an increase of hENT1 and/or dCK genes at least in one time-point. With respect to gene expression levels at basal time, dCK increased both early (+1h: 3 out of 9 valuable cycles; + 4–6 hrs: 4 out of 9 cycles) and late (+ 24–48 hrs: 5 out of 9 cycles); hENT1 increased poorly at +1h (1 out of 6 valuable cycles) but consistently at + 4–6 hrs (5 out of 6 cycles) and late (+24–48 hrs: 6 out of 6 cycles). The increase of dCK and hENT1 gene expression was from + 15% to 285% and from 21% to + 380%, respectively. Conclusions: MTA induces GCB- related genes both at early and late time points with an inter-patients variability. The most rationale time interval between the two drugs administration will be valuated at the completion of the study.

No significant financial relationships to disclose.

Linezolid cerebrospinal fluid concentration in central nervous system infection

We report two cases of central nervous system infection due to methicillin-resistant Staphylococcus epidermidis treated with linezolid. The first case was a 72-year old woman with ventriculitis in the presence of intraventricular catheter: therapeutic effectiveness was documented clinically and microbiologically; serum and cerebrospinal fluid levels were measured after the first and fourth doses: trough linezolid concentrations in cerebrospinal fluid were 1.44 and 2.9 mg/L respectively, higher than the minimum inhibitory concentration (MIC). The second case was a 27-year old man with post-traumatic cerebral abscess; during 5 days linezolid was not found in his cerebrospinal fluid despite very high serum level peak, and the drug was not detectable in cerebral tissue surgically removed after 14 days of therapy. Linezolid may not reach therapeutic concentrations in cerebrospinal fluid, and, when possible, we suggest that drug levels be monitored.