Biological determinants of blood-based cytokines in the Alzheimer's disease clinical continuum.

Converging translational and clinical research strongly indicates that altered immune and inflammatory homeostasis (neuroinflammation) plays a critical pathophysiological role in Alzheimer's disease (AD), across the clinical continuum. A dualistic role of neuroinflammation may account for a complex biological phenomenon, representing a potential pharmacological target. Emerging blood-based pathophysiological biomarkers, such as cytokines (Cyt) and interleukins (ILs), have been studied as indicators of neuroinflammation in AD. However, inconsistent results have been reported probably due to a lack of standardization of assays with methodological and analytical differences. We used machine-learning and a cross-validation-based statical workflow to explore and analyze the potential impact of key biological factors, such as age, sex, and apolipoprotein-E (APOE) genotype (the major genetic risk factor for late-onset AD) on Cyt. A set of Cyt was selected based on previous literature, and we investigated any potential association in a pooled cohort of cognitively healthy, mild cognitive impairment (MCI), and AD-like dementia patients. We also performed explorative analyses to extrapolate preliminary clinical insights. We found a robust sex effect on IL12 and an APOE-related difference in IL10, with the latter being also related to the presence of advanced cognitive decline. IL1ß was the variable most significantly associated with MCI-to-dementia conversion over a 2.5 year-clinical follow-up. Although preliminary, our data support further clinical research to understand whether plasma Cyt may represent reliable and noninvasive tools serving the investigation of neuroimmune and inflammatory dynamics in AD and to foster biomarker-guided pathway-based therapeutic approaches, within the precision medicine development framework.

Mitochondrial non-syndromic sensorineural hearing loss: a clinical, audiological and pathological study from Italy, and revision of the literature.

Over the last decade, a number of distinct mutations in the mtDNA (mitochondrial DNA) have been found to be associated with both syndromic and non-syndromic forms of hearing impairment. Their real incidence as a cause of deafness is poorly understood and generally underestimated. Among the known mtDNA mutations, the A1555G mutation in the 12S gene has been identified to be one of the most common genetic cause of deafness, and it has been described to be both associated to non-syndromic progressive SNHL (sensorineural hearing loss) and to aminoglycoside-induced SNHL. In the present study, we have investigated the presence of mtDNA alterations in patients affected by idiopathic non-syndromic SNHL, both familiar and sporadic, in order to evaluate the frequency of mtDNA alterations as a cause of deafness and to describe the audiological manifestations of mitochondrial non-syndromic SNHL. In agreement with previous studies, we found the A1555G mutation to be responsible for a relevant percentage (5.4%) of cases affected with isolated idiopathic sensorineural hearing impairment.

PPARgamma inhibits GH synthesis and secretion and increases apoptosis of pituitary GH-secreting adenomas.

OBJECTIVE: The objective of the study was to evaluate the expression and functional activity of Peroxisome proliferator-activated receptor (PPAR) gamma in pituitary adenomas from 14 consecutive acromegalic patients and to establish its role in apoptosis. SUBJECTS AND METHODS: Fourteen consecutive acromegalic patients were enrolled in the study. Wistar-Furth rats were used for in vivo studies. Expression of PPARgamma was evaluated by RT-PCR and Western blot. Apoptosis and cell cycle were assessed by FACS analysis. The effects of PPARgamma ligands on transcriptional regulation of GH gene were evaluated by RT-PCR and electromobility shift assay. RESULTS: PPARgamma was expressed in all human GH-secreting adenoma (GH-oma), in normal pituitary tissue samples (39+/-24% and 78+/-5% of immunostained nuclei respectively; P<0.0002; ANOVA), and in rat GH-secreting (GH3) cells. A PPRE-containing reporter plasmid transfected into GH3 cells was activated by ciglitazone or rosiglitazone (TZDs), indicating that PPARgamma was functionally active. Treatment of GH3 cells with TZDs increased apoptosis in a dose-dependent manner (P=0.0003) and arrested cell proliferation, reducing the number of cells in the S-phase (P<0.0001 vs untreated cells). TZDs increased the expression of TRAIL, leaving unaffected that of p53 and Bax. TZDs reduced GH concentrations in the culture media from 43.7+/-5.4 ng/ml to 2.1+/-0.3 ng/ml (P<0.0001) and in cell extracts (P<0.004). PPARgamma-RXRalpha heterodimers bound to GH promoter, inhibiting its activity and reducing GH mRNA levels (1.8 x 10(6) vs 5.7 x 10(6) transcripts respectively vs untreated cells; P<0.002). Subcutaneous GH-oma developed in rats injected with GH3 cells; tumor growth increased in placebo-treated rats and to a lesser extent in TZDs-treated animals (24.1+/-2.0 g, and 14.8+/-4.2 g respectively, P<0.03). Serum GH concentrations were lower in TZDs-treated rats than in controls (871+/-67 ng/ml vs 1.309+/-238 ng/ml; P<0.05). CONCLUSIONS: The results of this study indicate that PPARgamma controls GH transcription and secretion as well as apoptosis and growth of GH-oma; thus, TZDs have the potential of a useful tool in the complex therapeutic management of acromegalic patients.

Changes in the expression of the peroxisome proliferator-activated receptor gamma gene in the colonic polyps and colonic mucosa of acromegalic patients.

Acromegalic patients have an increased prevalence of colonic neoplasms and lower peroxisome proliferator-activated receptor gamma (PPARgamma) levels, the latter acting as a tumor suppressor gene. In this study we evaluated the expression of PPARgamma in the biopsy samples of the polyps and outside polyps colonic mucosa from seven patients with active, untreated acromegaly, 11 with cured disease, and 15 controls. Serum GH and IGF-I levels were higher in patients with untreated acromegaly than in those with acromegaly in remission or controls (P = 0.003 and P = 0.002, respectively) The expression of PPARgamma mRNA (mean +/- SE) was 1) mucosa outside polyps, 24,188 +/- 3,254 transcripts in the controls, 22,432 +/- 2,006 transcripts in acromegaly in remission, and 1,952 +/- 342 transcripts in untreated acromegaly (P < 0.0001 vs. controls and acromegaly in remission); and 2) polyps mucosa, 1,554 +/- 236 transcripts in the controls, 1,112 +/- 143 in acromegaly in remission, and 1,570 +/- 251 in untreated acromegaly (P = NS among polyps groups and mucosa outside polyps of untreated acromegaly; P < 0.0001 vs. mucosa outside polyps of controls and acromegaly in remission). Eighty-five percent of the cells in the mucosa outside polyps from controls or acromegaly in remission were positive at immunohistochemistry, at variance with 45% of the cells from polyps mucosa from each group and from those of mucosa outside polyps of untreated acromegaly (P = 0.0002). In conclusion, patients with untreated acromegaly have reduced expression of PPARgamma in the mucosa outside polyps, which might be reversed by curing the disease; conversely, patients with acromegaly in remission have the same low levels of expression of PPARgamma in the polyps mucosa as untreated acromegaly or controls, supporting the concept that reduced expression of PPARgamma might be an early event in colonic tumorigenesis.

Vascular endothelial growth factor (VEGF) expression in primary tumors and peritoneal metastases from patients with advanced ovarian carcinoma.

BACKGROUND: Several experimental and clinical data suggest that vascular endothelial growth factor (VEGF) is involved in ovarian carcinogenesis. However, there are no conclusive data about the prognostic value of tissue VEGF expression in this malignancy. The aim of the present investigation was to compare VEGF immunostaining in primary tumors and peritoneal metastases from patients with advanced ovarian carcinoma and to assess whether this parameter has a predictive or prognostic relevance. MATERIALS AND METHODS: The investigation was conducted on 45 patients who underwent initial surgery followed by platinum-based or paclitaxel/platinum-based chemotherapy for advanced ovarian carcinoma. Both primary tumors and peritoneal metastases were immunohistochemically analyzed for VEGF expression. Intense staining score was assigned if more than 75% of the cells stained positive. RESULTS: Intense VEGF immunostaining was detected in 14 and 36 (31.1% versus 80.0%, p < 0.0001), respectively, of primary tumors and peritoneal metastases. Twenty-six (57.8%) patients showed an increased VEGF immunostaining in metastatic lesions compared with primary tumors. VEGF immunostaining in primary tumors, VEGF immunostaining in peritoneal metastases and change in VEGF immunostaining from the primary tumor to peritoneal metastatic lesion were related neither to the response to chemotherapy nor to progression-free survival. CONCLUSION: In patients with advanced ovarian carcinoma, intense VEGF immunostaining was more often detected in peritoneal metastases than in primary tumors. VEGF immunostaining in primary as well as in metastatic lesions correlated neither with the response to chemotherapy nor with the clinical outcome. Therefore the immunohistochemical detection of VEGF in tissue samples collected during primary surgery failed to have a predictive or prognostic relevance for patients with advanced ovarian carcinoma.

Isolation and clonal analysis of human epidermal keratinocyte stem cells in long-term culture.

We developed a procedure for growing normal epidermal keratinocyte stem cells isolated from a single punch biopsy of adult human skin in long-term culture. Primary skin epithelial cells were maintained in collagen-coated plates with irradiated human neonatal foreskin fibroblasts (line HPI.1) as a feeder for more than 120 days, approximately 115 population doublings, without signs of replicative senescence. Clonal analysis revealed the presence of holoclones, meroclones, and paraclones. Only emerging colonies with high proliferative potentials and extensive capacities for division (holoclones and meroclones) were subcultured, favoring the expansion of stem cells and progenitors capable of prolonged self-maintenance when subcloned, thus accounting for the prevailing long-term proliferation of the original culture. We found that meroclones included bipotent progenitors capable of generating both keratinocytes and mucin-producing cells. The numbers of these cells were greater after confluence, suggesting that commitment for their differentiation occurred late in the life of a single clone. On a three-dimensional gelatin matrix and on a collagen layer containing the fibroblast feeder, cells isolated from the expansion of holoclones and meroclones formed stratified cohesive layers of keratinocytes that were able to further differentiate, as in normal skin. These results indicate that our procedure will serve as a valuable tool to study expansion of epidermal stem cells as well as the growth mechanisms and cell products associated with their growth and differentiation.

Intratumoral microvessel density, response to chemotherapy and clinical outcome of patients with advanced ovarian carcinoma.

BACKGROUND: The aim of this study was to assess intratumoral microvessel density (IMD) in tissue samples from primary ovarian carcinomas, and to correlate this angiogenic parameter with the common clinico-pathological variables, response to chemotherapy and prognosis of patients with this malignancy. PATIENTS AND METHODS: The investigation was conducted on 64 patients who underwent initial surgery for FIGO stages I-IV ovarian carcinoma. Paraffin-embedded sections of primary tumor specimens were analyzed for IMD by immunohistochemistry using anti-CD34 antibodies. In detail, we assessed the 49 patients with advanced (FIGO stages II-IV) disease. Postoperative chemotherapy consisted of paclitaxel/platinum-based chemotherapy in 36 (73.5%) patients and platinum-based chemotherapy in 13. RESULTS: The IMD ranged from 6 to 115 microvessels/field, with a median value of 40, and correlated with none of the common clinico-pathological variables of ovarian carcinoma. As for the patients with advanced disease, women with elevated IMD (> or = 40 microvessels/field) had a higher chance of achieving a complete response to chemotherapy when compared to those with lower IMD (p = 0.0068). Multiple logistic regression showed that IMD was an independent predictor of complete response to chemotherapy (p = 0.0094). By log-rank test, patients with elevated IMD had a better progression-free survival (p = 0.0039) and a better overall survival (p = 0.0365) when compared to those with lower IMD. The Cox model showed that IMD was the only independent prognostic variable for both progression-free survival (p = 0.0112) and overall survival (p = 0.0296). DISCUSSION: The present retrospective analysis seems to show a positive association between IMD, response to chemotherapy, mainly represented by a paclitaxel/platinum-based regimen, and clinical outcome of patients with advanced ovarian carcinoma.