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Landolfi, S.

Publications and source records attributed to Landolfi, S..

3 recordsLinked to original sources

From Splicing to Survival: Understanding the Molecular Basis of Prognostic Differences in advanced Small Intestine Neuroendocrine Tumors

Small intestine neuroendocrine tumors (SI-NETs) represent a challenging neoplasm due to their high rate of metastasis and the limited availability of effective therapies. Recent evidence has unveiled altered splicing as an influential player in tumor progression, linked to patient prognosis, which provides a powerful source of novel biomarkers and therapeutic targets in cancer. Here, we conducted a comprehensive analysis regarding the possible connection of the spliceosomic landscape of metastatic SI-NETs with patient survival. Initial analyses revealed a distinctive pattern of splicing events between the two conditions, short (< 5 years, n = 17 patients), vs. long survival ([&ge;] 5 years, n = 26 patients), with strong discrimination capacity. Furthermore, numerous key splicing events were associated with relevant clinical parameters in SI-NETs. The observed impairments in spliceosomic parameters led us to interrogate the integrity of the splicing machinery. This revealed striking changes in the expression of a high proportion of core spliceosome components and splicing factors between short vs. longsurvival groups, suggesting a possible mechanistic link with the distinct profile of splicing events observed. Among them, CPSF2, a core component of the CPSF complex, stands out as its higher expression is associated with worse survival and vascular and perineural invasion. Interestingly, the shifts potentially generated by this factor supported a possible role in tumor plasticity oriented to higher tumor aggressiveness and treatment resistance. In sum, this study offers the first detailed snapshot of the status of the spliceosomic landscape in SI-NETs and its molecular linkage to patient survival, thus offering a new window towards identification of novel candidate biomarkers and/or therapeutic targets.

cancer biology↗

Site-Specific Entry Factors Define Cellular Susceptibility to SARS-CoV-2 in Human Tissues

SARS-CoV-2 primarily infects the respiratory epithelium through entry factors ACE2 and TMPRSS2. However, alternative viral entry receptors and/or modulators of viral entry factors expression may contribute to infection in respiratory as well as non-respiratory tissues, including the kidneys and colon. Using single-cell analyses, we identified novel candidates for spike-mediated viral entry in epithelial cells from diverse fresh human tissues exposed to a labeled spike-pseudotyped virus. Systematic viral tracking revealed tissue-specific membrane receptors that contribute to viral entry, functionally validated in human tissues and partially predicted by molecular modeling. We found ADAM17 and IL1R1, together with canonical molecules, to significantly facilitate viral entry in the lung parenchyma, while entry into the renal cortex was less dependable on canonical factors, but strongly modulated by JAK1/2 engagement. These findings uncover distinct viral entry mechanisms across tissues and suggest novel organ-specific therapeutic targets for patients at risk.

microbiology↗

Identification of the Inducible HIV reservoir in Tonsillar, Intestinal and Cervical Tissue Models of HIV Latency

HIV persists in diverse tissues, with distinct cellular reservoirs presenting a major barrier to a cure and requiring targeted therapeutic strategies to address this heterogeneity. Here, we developed tissue models of HIV latency using human tonsillar, intestinal and cervicovaginal tissues. These models revealed differential HIV infection across CD4+ T cell subpopulations, with ART partially restoring CD4+ T cells and reducing intact HIV DNA. T follicular helper cells (TFH CD69+ CCR7-) were the primary inducible reservoir in tonsils, while tissue-resident memory cells (TRM CD69+ CD49a+) dominated in the intestine. Identification of markers for inducible reservoirs revealed that CD69, CD45RO, and PD-1 were shared across tissues, while CXCR5 in the tonsils and CD49a in the intestine served as tissue-specific markers. Furthermore, using different latency reversal agents (LRAs) we found that Histone Deacetylase Inhibitors (HDACis) failed to induce HIV in any tissue, the SMAC mimetic AZD5582 was effective only in a resident-memory CD4+ T cell subpopulation in the intestine, and IL15 exhibited the broadest reactivation potential across tissues and CD4+ T subsets. These models recapitulate key aspects of HIV infection providing insights into the inducible reservoirs composition in different tissues and informing strategies for its elimination.

immunology↗