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Biology subjects

Pazienza, V.

Publications and source records attributed to Pazienza, V..

3 recordsLinked to original sources

p53 knockout drives stage-specific long non-coding RNA reprogramming during human neural differentiation and glioma organoid tumorigenesis.

Background: Long non-coding RNAs (lncRNAs) are emerging regulators of tumor initiation and progression through their effects on stemness, lineage commitment, and transcriptional plasticity. The contribution of lncRNA reprogramming during early p53-deficient gliomagenesis remains poorly understood. Methods: Human induced pluripotent stem cells (iPSCs) carrying a complete TP53 knockout were differentiated into neural progenitor cells (NPCs) and cerebral organoids. Bulk RNA sequencing was performed at multiple differentiation stages and compared with established glioblastoma cell lines (U87 and U118) to identify lncRNA expression changes associated with p53 loss and tumor-like transformation. Results: p53 deficiency induced a progressive and stage-specific remodeling of the lncRNA landscape, with the most pronounced transcriptional shift observed in 40-day NPCs. This late-stage profile partially overlapped with glioblastoma-like cell lines and was characterized by the upregulation of five lncRNAs enriched in both p53-deficient neural models and glioma cells. Principal component analysis showed that these lncRNAs clustered with tumor-associated samples and were strongly co-expressed with mitotic cell-cycle genes. In particular, LINC00973 and LINC01583 were highly expressed in primary glioblastoma datasets, while RP5-875H18.9 and RP11-1094H24.4 emerged as previously unrecognized glioma-associated transcripts. Conclusion: Loss of p53 drives stage-dependent lncRNA reprogramming during neural differentiation and promotes the emergence of glioma-associated transcriptional features. These findings identify candidate lncRNAs that may contribute to early gliomagenesis and represent potential biomarkers or therapeutic targets in glioblastoma.

cancer biology↗

Interplay of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans along with Circulating miR-21 and miR-155 as Potential Biomarkers for Pancreatic Cancer

The associations between oral bacterial pathogens and the risk of pancreatic cancer (PC) have been reported in several epidemiological studies. In this study, we evaluated the diagnostic potential of periodontal pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans in combination with circulating oncomiRNAs, including miR-21 and miR-155. A total of 41 PC patients and 40 age- and sex-matched controls were recruited for the study. The salivary bacterial load of P. gingivalis and A. actinomycetemcomitans, along with the copy number of miR-21 and miR-155 in blood, were measured using quantitative real-time PCR. Subsequently, the predictive power of the selected biomarkers in PC diagnosis was determined. Elevated load of the periodontal pathogens P. gingivalis in females (OR=2.31; 95% CI 0.98-5.47) and A. actinomycetemcomitans in diabetic individuals (OR=3.66; 95% CI 0.47-6.68) were associated with a higher risk of PC. Moreover, the diagnostic model incorporating two salivary species and two circulating miRNAs demonstrated an AUC of 0.878 (95% CI 0.802-0.955). This study offers compelling new evidence supporting the idea that the combined analysis of salivary microbiota and circulating miRNAs serves as an informative avenue for the discovery of non-invasive biomarkers for PC.

molecular biology↗

Low-protein/high-carbohydrate diet induces AMPK-dependent canonical and non-canonical thermogenic response in subcutaneous adipose tissue

Low-protein/high-carbohydrate (LPHC) diet promotes metabolic health and longevity in adult humans and animal models. However, the complex molecular underpinnings of how LPHC diet leads to metabolic benefits remain elusive. Through a multi-layered approach, here we observed that LPHC diet promotes an energy-dissipating response consisting in the parallel recruitment of canonical and non-canonical (muscular) thermogenic systems in subcutaneous white adipose tissue (sWAT). In particular, we measured Ucp1 induction in association with up-regulation of actomyosin components and several Serca (Serca1, Serca2a, Serca2b) ATPases. In beige adipocytes, we observed that AMPK activation is responsible for transducing the amino acid lowering in an enhanced fat catabolism, which sustains both Ucp1- and Serca-dependent energy dissipation. Limiting AMPK activation counteracts the expression of brown fat and muscular genes, including Ucp1 and Serca, as well as mitochondrial oxidative genes. We observed that mitochondrial reactive oxygen species are the upstream molecules controlling AMPK-mediated metabolic rewiring in amino acid-restricted beige adipocytes. Our findings delineate a novel metabolic phenotype of responses to amino acid shortage, which recapitulates some of the benefits of cool temperature in sWAT. In conclusion, this highlights LPHC diet as a valuable and practicable strategy to prevent metabolic diseases through the enhancement of mitochondrial oxidative metabolism and the recruitment of different energy dissipating routes in beige adipocytes.

physiology↗