Neuroprotective coordination of cell mitophagy by the ATPase Inhibitory Factor 1.

The mitochondrial ATPase Inhibitory Factor 1 (hereafter referred to as IF1) blocks the reversal of the F1Fo-ATPsynthase to prevent detrimental consumption of cellular ATP and associated demise. Herein, we infer further its molecular physiology by assessing its protective function in neurons during conditions of challenged homeostatic respiration. By adopting in vitro and in vivo protocols of hypoxia/ischemia and re-oxygenation, we show that a shift in the IF1:F1Fo-ATPsynthase expression ratio occurs in neurons. This increased IF1 level is essential to induce accumulation of the PTEN-induced putative kinase 1 (PINK-1) and recruitment of the mitophagic ubiquitin ligase PARK-2 to promote autophagic "control" of the mitochondrial population. In IF1 overexpressing neurons ATP depletion is reduced during hypoxia/ischemia and the mitochondrial membrane potential (ΔYm) resilient to re-oxygenation as well as resistant to electrogenic, Ca(2+) dependent depolarization. These data suggest that in mammalian neurons mitochondria adapt to respiratory stress by upregulating IF1, which exerts a protective role by coordinating pro-survival cell mitophagy and bioenergetics resilience.

Cell metabolism sets the differences between subpopulations of satellite cells (SCs).

BACKGROUND: We have recently characterized two distinct populations of Satellite Cells (SCs) that differ in proliferation, regenerative potential, and mitochondrial coupling efficiency and classified these in Low Proliferative Clones (LPC) and High Proliferative Clones (HPC). Herewith, we have investigated their cell metabolism and individuated features that remark an intrinsic difference in basal physiology but that are retrievable also at the initial phases of their cloning. RESULTS: Indeed, LPC and HPC can be distinguished for mitochondrial membrane potential (ΔΨm) just after isolation from the fiber. This is matched by mitochondrial redox state measured via NAD⁺/NADH analysis and alternative respiratory CO2 production in cloned cells. All these parameters are accountable for metabolic differences reflected indeed by alternative expression of the glycolytic enzyme 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (Pfkfb3). Also Ca²âº handling by mitochondria is different together with the sensitivity to apoptosis triggered via this pathway. Finally, according to the above, we were able to determine which one among the clones represents the suitable stem cell. CONCLUSIONS: These experimental observations report novel physiological features in the cell biology of SCs and refer to an intrinsic heterogeneity within which their stemness may reside.

Gastric cancer with high-level microsatellite instability: target gene mutations, clinicopathologic features, and long-term survival.

Gastric cancer is one of the leading causes of cancer death worldwide, and although the incidence has decreased in Western countries, specific high-risk areas are present in Italy. Gastric cancer with high-level microsatellite instability (MSI-H) represents a well-defined subset of carcinomas showing distinctive clinicopathologic features. We examined clinicopathologic associations and long-term survival in a series of 159 gastric cancer cases from a high-risk population in Tuscany (central Italy). MSI-H was associated with antral location of the tumor (P = .001), intestinal type according to Lauren classification (P = .002), expanding type according to Ming classification (P = .0001), and mucinous histologic type according to the Japanese Research Society for Gastric Cancer classification (P = .002). In addition, MSI-H was strongly associated with a higher survival at 15 years (P = .01) and with loss of hMLH1 expression, evaluated by immunohistochemistry (P = .001). Multivariate analyses showed a significant association between the absence of hMLH1 reactivity and the expanding tumor type (P = .002). We also investigated the MSI-H-related genetic changes by analyzing coding repeats within target genes involved in pathways that control cell growth (TGFbetaRII, IGFIIR, RIZ, TCF4, DP2), apoptosis (BAX, BCL10, FAS, CASPASE5, APAF1), and DNA repair genes (hMSH6, hMSH3, MED1, RAD50, BLM, ATR, BRCA2, MRE11). Gastric cancer cases with MSI-H were found to accumulate heterozygous mutations affecting multiple molecular pathways and multiple genes within each pathway. Intriguingly, in this subset, TGFbetaRII mutations appeared to be inversely related to BLM mutations (P = .006), whereas RAD50 mutation carriers showed significantly reduced survival (P = .03).

BRCA1/BRCA2 rearrangements and CHEK2 common mutations are infrequent in Italian male breast cancer cases.

Male breast cancer (MBC) is a rare and poorly known disease. Germ-line mutations of BRCA2 and, to lesser extent, BRCA1 genes are the highest risk factors associated with MBC. Interestingly, BRCA2 germ-line rearrangements have been described in high-risk breast/ovarian cancer families which included at least one MBC case. Germ-line mutations of CHEK2 gene have been also implicated in inherited MBC predisposition. The CHEK2 1100delC mutation has been shown to increase the risk of breast cancer in men lacking BRCA1/BRCA2 mutations. Intriguingly, two other CHEK2 mutations (IVS2+1G>A and I157T) and a CHEK2 large genomic deletion (del9-10) have been associated with an elevated risk for prostate cancer. Here, we investigated the contribution of BRCA1, BRCA2 and CHEK2 alterations to MBC predisposition in Italy by analysing a large series of MBC cases, unselected for breast cancer family history and all negative for BRCA1/BRCA2 germ-line mutations. A total of 102 unrelated Italian MBC cases were screened for deletions/duplications of BRCA1, BRCA2 and CHEK2 by multiplex ligation-dependent probe amplification. No BRCA1, BRCA2 and CHEK2 genomic rearrangements, including the CHEK2 del9-10, were found in the series analysed. Furthermore, none of the MBC cases and 263 male population controls, also included in this study, carried the CHEK2 1100delC, IVS2+1G>A and I157T common mutations. Overall, our data suggest that screening of BRCA1/2 rearrangements is not advantageous in MBC cases not belonging to high-risk breast cancer families and that common CHEK2 mutations play an irrelevant role in MBC predisposition in Italy.

Association between the BRCA2 N372H variant and male breast cancer risk: a population-based case-control study in Tuscany, Central Italy.

BACKGROUND: Male breast cancer (MBC) is a rare disease and little is known about its aetiology. Germ-line mutations of BRCA2 and, at lower frequency, of BRCA1 are implicated in a relatively small proportion of MBC cases. Common polymorphic variants in BRCA1 and BRCA2 genes may represent breast cancer (BC) susceptibility alleles and could be associated with a modestly increased risk of MBC at population level. Considering the relevant role of BRCA2 in MBC, we investigated whether the BRCA2 N372H variant, representing the only common non-synonymous polymorphism in BRCA2, might modulate the risk of BC in male populations. METHODS: A case-control study was performed comparing a population-based series of 99 MBC cases, characterized for BRCA1 and BRCA2 mutations, with 261 male population controls, all residing in Tuscany, Central Italy. All MBC cases and controls were genotyped for the BRCA2 N372H allele by TaqMan allelic discrimination assays. To evaluate the genotype specific risk of the BRCA2 N372H variant, MBC carriers of germ-line BRCA1/2 mutations were excluded from the analyses. RESULTS: No association emerged in univariate and age-adjusted analyses. Age-specific analyses suggested an increased risk for the HH homozygous genotype in subjects younger than 60 years. A statistically significant interaction emerged between this genotype and age (p = 0.032). When analyses were restricted to MBC cases enrolled in the first 4 years following diagnosis, a recessive model showed a significantly increased risk of MBC in HH subjects younger than 60 years (OR = 5.63; 95% CI = 1.70;18.61). CONCLUSION: Overall, our findings, although based on a relatively small series, suggest that the BRCA2 HH homozygous genotype might be positively associated with an increased risk of MBC in men younger than 60 years.

[From cellular biology to molecular biology: Golgi apparatus from the discovery to nowadays]. / Dalla biologia cellulare alla biologia molecolare: l'apparato di Golgi dalla sua scoperta ai nostri giorni.

On April the 9th 1898 Golgi presented the discovery of the Apparato Reticolare Interno or internal reticular apparatus to the Società Medico-Chirurgica in Pavia. The internal reticular apparatus was described as "a fine and elegant network within the cell body" of Purkinje cells. The discovery of this new intracellular structure can be considered a byproduct of Golgi studies devoted to the analysis of the nervous system histology. Golgi and his co-workers detected the internal reticular apparatus in many cell types and described the organelle pleiomorphism due to specific physiological or pathological conditions. However, the real existence of the apparatus was questioned until the organelle was finally identified by electron microscopy in 1954. At this point Golgi apparatus became an actual intracellular structure without any clear function. The involvement in cell secretion processes was verified by using biochemical and molecular investigations from the 1960s. Nowadays, Golgi apparatus is clearly known to be involved in different cell functions as growth, homeostasis and division. The correct execution of these functions lies on the ability to maintain an equilibrated balance between the proteins therein resident. Recently, Golgi apparatus has been involved also in human pathology as mutations in proteins localized in the organelle are linked to some hereditary disorders like the Lowe syndrome. Golgi apparatus has been debated since its discovery. From the Golgi milestones discussed here it is evident that controversies that have arisen were often resolved by information resulting from the application of new technical developments. Indeed the compound dynamic structure and the relevance in cell physiology and in human pathology render Golgi apparatus an open object for future studies. Overall, the history of the Golgi apparatus represents an excellent model not only to follow the transition of the study approaches from cellular biology to molecular cell biology but also to understand the current attention paid to integrate the molecular function and the organelle structure in order to explain what goes wrong in the context of human disease.

ErbB-receptors expression and survival in breast carcinoma: a 15-year follow-up study.

Aberrant expression of the epidermal growth factor receptor family has been implicated in the pathogenesis and progression of breast cancer and associated with poor prognosis. To evaluate the prognostic impact of the ErbB receptors expression profile, we analyzed a well-characterized series of 145 primary breast carcinomas for the simultaneous expression of epidermal growth factor receptor (EGFR/HER-1), ErbB-2 (HER-2), ErbB-3 (HER-3), and ErbB-4 (HER-4), using immunohistochemistry. Tumors were considered negative or positive for each marker when less than or more than 25% of the cancer cells were immunopositive. Expression of EGFR, ErbB-2, ErbB-3, and ErbB-4 was observed in 31 (21.4%), 65 (44.8%), 72 (49.7%), and 81 (55.9%) of the cases, respectively. There were significant associations between EGFR expression and pT status (P = 0.01), and between ErbB-3 expression and pN (P = 0.003), menopausal (P = 0.01) and PR (P < 0.001) status. The majority of the cases co-expressed two or more receptors. ErbB-3 resulted positive in 51/81 (63.0%) of the ErbB-4 positive cases and ErbB-3/ErbB-4 co-expression was statistically significant (P = 0.0003). As expected, ErbB-2 expression was associated with reduced overall survival at 15 years of follow-up (P = 0.04), even after adjusting for a series of other prognostic factors (P = 0.05). Moreover, cumulative analysis of ErbB-2/3/4 expression showed a strong positive association between higher total ErbB-2/3/4 expression score and worse prognosis (P = 0.002). The simultaneous expression in cancer cells of more than one ErbB receptor identifies a subset of breast cancer patients at high risk for poor survival.

[Prevention of mediterranean anemia in Latium: Ida Bianco archives]. / La prevenzione dell'anemia Mediterranea nel Lazio: i documenti dell'archivio Ida Bianco.

Mediterranean anemia or beta-thalassemia is a hereditary syndrome characterized by a severe defect in haemoglobin production and an altered morphology of red blood cells. Homozygous condition for beta-thalassemia is characterized by short survival. Heterozygous condition is clinically found in adolescence and is characterized by a less aggressive phenotype. Ida Bianco, with her husband Ezio Silvestroni, has conducted a long struggle for beta-thalassemia prevention in Italy. They were the first to draw up an accurate map of the distribution of thalassemia in Italy and to conceive and implement a campaign against this genetic disease by the development of annual screening on at-school teenagers and pre-marriage prevention. Here we focused on the analysis of Ida Bianco's archives concerning screenings conducted on middle-schools in the Latium by the "Centro Studi della Microcitemia" of Rome from 1975 up to today. The results of the thirty-years prevention work in the Latium will be described.

[Molecular paleopathology: a novel perspective for biomedical history]. / La paleopatologia moleceolare: il futuro per indagare il passato.

Molecular paleopathology is an emerging field that is devoted to the detection, indentification and characterization of the molecular signatures in past diseases. When studied with modern molecular techniques, ancient human remains may yield direct informations on the diseases of ancient populations as well as the history of human diseases. Data concerning specific diseases of infectious, neoplastic and genetic origin can be obtained by molecular investigations of skeletal and mummified human remains. In particular, ancient DNA extracted from bone tissue, teeth and mummified soft tissue can be deeply analyzed by using PCR-based molecular techniques. Additionally, DNA of ancient pathogens, including bacteria, viruses and parasites, can be isolated from human remains and molecular diagnosis of infectious diseases can be made. Thus, molecular data, complemented by morphological and biochemical analyses, could help to reconstruct the epidemiology of past diseases and epidemics.

TP53 in gastric cancer: mutations in the l3 loop and LSH motif DNA-binding domains of TP53 predict poor outcome.

The aim of this study was to clarify whether specific p53 mutations may have biological relevance in terms of disease relapse or death in gastric carcinomas (GC). Resected specimens from a consecutive series of 62 patients with GC undergoing potentially curative surgery were prospectively studied. The mutational status of exons 5-8 of the p53 gene was investigated in 62 cases using the PCR-SSCP and sequencing. Presence of microsatellite instability (MSI) was evaluated in 56 cases by analyzing loci highly sensitive of MSI. Twenty mutations of p53 were detected in 17 of the 62 cases analyzed (27%). Ten mutations (50%) occurred in highly conserved domains. According to the p53 specific functional domains: 4/20 mutations (20%) were in the L3 loop and 3/20 (15%) in LSH motif. Eight of the 56 GC resulted MSI-H, 5 (9%) MSI-L, and 43 (77%) MSI stable (MSS). None of the 8 (14%) MSI-H GC showed p53 mutations. p53 mutations were associated with intestinal histotype. Moreover, specific mutations in functional domain (L3 and LSH), together with advanced TNM stage, node involvement, depth of invasion, diffuse histotype, proved to be significantly related to quicker relapse and to shorter overall survival. Specific mutations in p53 functional domains, rather than any mutations in this gene, may be biologically more significant in terms of patients outcome, indicating that these mutations might have biological relevance to identify subgroups of patients at higher risk of relapse or death who might benefit from a more aggressive therapeutic approach.