Gene therapy approaches for epidermolysis bullosa

Human epidermis consists of a stratified epithelium mainly composed of keratinocytes and relies on a stem cell compartment to undergo constant regeneration. Genetic mutations affecting the capacity of basal keratinocytes to adhere firmly to the epidermal basement membrane lead to severe, and very often lethal, blistering disorders known as epidermolysis bullosa. Gene therapy represents a promising potential treatment for these devastating inherited disorders. Human epidermal stem cells can be cultivated ex vivo and stably transduced with integrating gene transfer vectors, allowing genetic and, more important, phenotypic correction of the adhesion properties of keratinocytes. Here we will review some of the issues that need to be addressed to make gene therapy a realistic treatment for these disorders, such as (1) which cells should be targeted, (2) which approach (in vivo or ex vivo) should be chosen, and (3) which gene transfer vector (retrovirus, lentivirus, or integrating nonviral strategies) should be used for stable gene correction. In the last 10 years, many reports have shown that gene transfer approaches to target epidermal stem cells are feasible and able to restore the adhesion properties of primary keratinocytes from patients with epidermolysis bullosa. In addition, tremendous progress has been achieved in culturing epidermal stem cells and generating sheets of stratified epithelium for permanent coverage of full-thickness burns. Gene modification of stem cells in combination with advanced tissue-engineering techniques could therefore represent a realistic option for patients with epidermolysis bullosa.     

Cytologic aspects of the nasal respiratory epithelium throughout the menstrual cycle

A prospective study was performed to investigate the changes in nasal cytology that occur in healthy premenopausal women throughout the menstrual cycle. Eighty-eight women with an ovulatory menstrual cycle underwent nasal sampling with a cytobrush by direct vision of the middle and inferior nasal turbinates during the follicular, periovular, and luteal phases of the menstrual cycle, and the specimens were evaluated with the maturation index. Hematoxylin-eosin staining showed the cytologic aspects of the nasal respiratory epithelium and of vaginal smears according to the three different phases of the menstrual cycle. Along with the vaginal cells, the nasal respiratory epithelium is an ovarian steroid target.     

Early diagnosis in hypertrophic cardiomyopathy--case report

Disproportionate heart muscle enlargement compared with little or no chamber enlargement are characteristic for hypertrophic cardiomyopathy (HCM). The clinical course of HCM is highly variable. Many patients are asymptomatic or mildly symptomatic and may be relatives of patients with known disease. Unfortunately, the first clinical manifestation of the disease may be sudden death, frequently occurring in children and young adults, often during or after physical exertion. We present 2 cases of HCM who emphasize the variability of clinical and ECG modifications and underline the importance of routine echocardiography in patients with atypical cardiac symptoms in order to identify the disease and prevent high risk for sudden death.     

Discrimination between uterine serous papillary carcinomas and ovarian serous papillary tumours by gene expression profiling

High-grade ovarian serous papillary cancer (OSPC) and uterine serous papillary carcinoma (USPC) represent two histologically similar malignancies characterised by markedly different biological behavior and response to chemotherapy. Understanding the molecular basis of these differences may significantly refine differential diagnosis and management, and may lead to the development of novel, more specific and more effective treatment modalities for OSPC and USPC. We used an oligonucleotide microarray with probe sets complementary to >10 000 human genes to determine whether patterns of gene expression may differentiate OSPC from USPC. Hierarchical cluster analysis of gene expression in OSPC and USPC identified 116 genes that exhibited >two-fold differences (P<0.05) and that readily distinguished OSPC from USPC. Plasminogen activator inhibitor (PAI-2) was the most highly overexpressed gene in OSPC when compared to USPC, while c-erbB2 was the most strikingly overexpressed gene in USPC when compared to OSPC. Overexpression of the c-erbB2 gene and its expression product (i.e., HER-2/neu receptor) was validated by quantitative RT-PCR as well as by flow cytometry on primary USPC and OSPC, respectively. Immunohistochemical staining of serous tumour samples from which primary OSPC and USPC cultures were derived as well as from an independent set of 20 clinical tissue samples (i.e., 10 OSPC and 10 USPC) further confirmed HER-2/neu as a novel molecular diagnostic and therapeutic marker for USPC. Gene expression fingerprints have the potential to predict the anatomical site of tumour origin and readily identify the biologically more aggressive USPC from OSPC. A therapeutic strategy targeting HER-2/neu may be beneficial in patients harbouring chemotherapy-resistant USPC.     

Melatonin in wake-sleep disorders in children, adolescents and young adults with mental retardation with or without epilepsy: a double-blind, cross-over, placebo-controlled trial

The aim of the present study was to verify the clinical efficacy of melatonin (MLT) in children, adolescents and young adults with wake-sleep disorder and mental retardation, most of them on chronic anticonvulsant therapy for epileptic seizures, by means of a randomized, double-blind, placebo-controlled cross-over trial. Twenty-five patients (16 males, nine females), aged from 3.6 to 26 years (mean 10.5 years), all affected with mental retardation mostly with epileptic seizures, were randomized to oral synthetic fast-release MLT or placebo. Melatonin was initiated at the daily dose of 3 mg, at nocturnal bedtime. In case of inefficacy, MLT dose could be titrated up to 9 mg the following 2 weeks at increments of 3 mg/week, unless the patient was unable to tolerate it. The analysis of all the sleep logs disclosed a significant treatment effect of melatonin on sleep latency (P = 0.019). Melatonin was well tolerated in all patients and no side effects were reported. In conclusion, our study supports the efficacy of MLT in young patients with mental disabilities and epileptic seizures in improving the wake-sleep disorders such as time to fall asleep. Overall, MLT appeared to influence the seizure frequency poorly, though there may be occasional seizure worsening or improving. Such a dual effect requires further studies in young epileptic patients.     

A novel mutation of myelin protein zero associated with an axonal form of Charcot-Marie-Tooth disease

OBJECTIVE: To report a new mutation in the MPZ gene which encodes myelin protein zero (P0), associated with an axonal form of Charcot-Marie-Tooth disease (CMT). METHODS: Three patients from an Italian family with a mild, late onset axonal peripheral neuropathy are described clinically and electrophysiologically. To detect point mutation in MPZ gene the whole coding sequence was examined. The structure of the mutated protein was investigated using the three dimensional model of P0. RESULTS: All patients showed a relatively mild CMT phenotype characterised by late onset and heterogeneity of the clinical and electrophysiological features. Molecular analysis demonstrated a novel heterozygous T/A transversion in the exon 3 of MPZ gene that predicts an Asp109Glu amino acid substitution in the extracellular domain of the P0. Asp109 is found at the protein surface, on beta strand E, in the interior of the P0 tetramer. CONCLUSIONS: The identification of Asp109Glu mutation confirms the pivotal role of P0 in axonal neuropathies and stresses the phenotypic heterogeneity associated with MPZ mutations. This study suggests the value of screening for MPZ mutations in CMT family members with minor clinical and electrophysiological signs of peripheral neuropathy.     

A novel mutation of GDAP1 associated with Charcot-Marie-Tooth disease in three Italian families: evidence for a founder effect

BACKGROUND: Mutations in a gene encoding a novel protein of unknown function-the ganglioside-induced differentiation-associated protein 1 gene (GDAP1)-are associated with the autosomal recessive Charcot-Marie-Tooth disease type 4A (CMT4A). OBJECTIVE: To investigate the role of GDAP1 mutations in causing autosomal recessive neuropathies in an Italian population. METHODS AND RESULTS: 76 patients with severe early onset polyneuropathy and possible autosomal recessive inheritance were screened for mutations. A T>G transversion (c.347 T>G) at codon 116 (M116R) was detected in four affected subjects from three apparently unrelated families. All patients had early onset of disease with pronounced foot deformities and impaired walking. Neurophysiological studies showed an extremely variable expression. Sural nerve biopsies revealed signs of both de-remyelination and axonal impairment, the most prominent feature being a severe loss of larger fibres. Haplotype analysis of the GDAP1 locus demonstrated a common disease haplotype. CONCLUSIONS: The association of the mutation with a common haplotype suggested a common ancestor.     

Selection of HER-2/neu-positive tumor cells in early stage cervical cancer: implications for Herceptin-mediated therapy

OBJECTIVE: The purpose of this study was to compare HER-2/neu expression on biopsies obtained from early stage cervical cancer, primary cell lines established therefrom, established cervical cancer cell lines, and metastatic or recurrent sites of disease; and to evaluate the sensitivity of primary cervical cancer cell lines to treatment with a humanized MAb against HER-2/neu (Herceptin). METHODS: Surface HER-2/neu expression on 18 cervical cancer cell lines was compared to HER-2/neu detection by immunohistochemistry on biopsies obtained from the original tumors (10 patients) and sites of recurrence (2 patients). Primary cell lines were tested for sensitivity to Herceptin-mediated antibody-dependent cellular cytotoxicity (ADCC) and sensitivity to Herceptin-mediated inhibition of proliferation. RESULTS: Nine out of 10 primary (90%) and 8 out of 8 (100%) established cervical cancer cell lines expressed HER-2/neu by flow cytometry. Surprisingly, all HER-2/neu-positive primary cell lines were derived from tumor biopsies that scored negative (i.e., 0 to 1+) for HER-2/neu expression by immunohistochemistry. Heavy staining for HER-2/neu (i.e., 3+) was found in the recurrent/metastatic lesions of the two relapsed patients. Importantly, all HER-2/neu-positive primary cell lines were highly sensitive to Herceptin-mediated ADCC, and their proliferation was also significantly inhibited by Herceptin. A significant enhancement of Herceptin-mediated ADCC was demonstrated when effector cells were exposed to low doses of IL-2 in vitro. CONCLUSIONS: Early stage cervical cancer may develop a population of HER-2/neu-positive cells with a selective growth advantage over HER-2/neu-negative cells. Therapy which targets HER-2/neu may be more effective in patients with cervical cancer than indicated by the commonly low expression of HER-2/neu in tumors removed at the time of primary treatment.