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Mannino, M.

Publications and source records attributed to Mannino, M..

6 recordsLinked to original sources

CATFISHR: integration of transcriptome and inferred CNV profiles for comprehensive malignant cell identification

Malignant cell identification in single-cell RNA sequencing (scRNA-seq) remains challenging because transcriptomic cell typing, somatic variant detection and inferred copy-number approaches each have modality-specific limitations. Rare or ambiguous malignant populations are especially vulnerable to misclassification or exclusion, despite their relevance to treatment resistance, minimal residual disease, and metastasis. We developed CATFISHR, a semi-automated workflow that integrates RNA-expression similarity, inferred copy-number variation (CNV) profiles, and consensus cell typing to classify malignant cells relative to high-confidence references. CATFISHR was evaluated across eight cohorts, including seven scRNA-seq datasets spanning multiple carcinomas and melanoma subtypes, and one 10x Visium spatial transcriptomics sample. Compared with available benchmarks or ground truths, CATFISHR achieved balanced accuracy > 0.85 in six of eight cohorts and F1 score > 0.80 in six of eight cohorts. Cells uniquely identified by CATFISHR as malignant ("Hidden" cells) were present in every dataset and were not consistently explained by standard quality-control metrics. In several cohorts, Hidden cells were transcriptionally closer to benchmark malignant than non-malignant compartments; in Visium data, sampled Hidden spots contained histologist-confirmed morphologically malignant cells. CATFISHR reduces missed malignant calls while preserving rare, transitional and benchmark-discordant populations for downstream investigation.

bioinformatics↗

Sustained interferon exposure creates a hyper-metastatic subset of melanoma cells

We generated interferon signaling reporters in human and mouse melanoma cells and observed heterogeneity in interferon responses among cells in the same tumors. This was marked by inflamed regions within primary tumors that contained increased numbers of interferon-expressing macrophages/monocytes and elevated type I interferon signaling in melanoma cells. Melanoma cells that expressed GFP-Interferon stimulated gene 15 (ISG15) or GFP-Interferon-induced protein with tetraticopeptide repeats 3 (IFIT3) fusion reporters exhibited a profoundly increased ability to form metastatic tumors as compared to GFP-ISG15- melanoma cells from the same tumors, particularly when transplanted into immunocompetent mice. The increased metastatic potential of GFP-ISG15+ cells was driven partly by increased CD47 expression, which protected metastasizing cells from phagocytosis by macrophages. Macrophages are thus a double-edged sword, inhibiting the development of metastatic disease by phagocytosing disseminated melanoma cells, but promoting the emergence of a hyper-metastatic subpopulation of cells in inflamed regions of primary tumors as a consequence of sustained interferon production. One sentence summarySustained interferon exposure within inflamed regions of primary tumors dramatically increases the metastatic potential of a subpopulation of melanoma cells, partly by promoting CD47 expression, which protects against phagocytosis by macrophages.

cancer biology↗

In vivo evidence for bleb-induced survival signaling in metastatic melanoma

Bleb signaling is a cellular process in which pressure-driven plasma membrane protrusions generate localized micron-scale membrane curvature that recruits cytosolic septin complexes, assembling signaling hubs that promote cell survival1. Our prior work showed that this morphology-encoded signaling pathway is necessary to sustain anchorage-independent survival of BRAF and NRAS mutant melanoma cells in vitro. However, whether bleb-induced signaling occurs in vivo and contributes to cancer progression is unclear. Here, we develop complementary in vivo and ex vivo assays spanning human patient samples and mouse xenograft models to mechanistically interrogate bleb signaling directly in physiologic contexts. We observe that bleb-associated septin hubs are exclusively formed in poorly adherent amoeboid tumor cells at the invasive margin, within malignant effusions, and at distant metastatic sites, while well-adhered cells in the tumor interior show no signs of septin hub formation. Accordingly, pharmacological pathway disruption specifically kills disseminated tumor cells within these low-adhesion microenvironments while having no appreciable effect on adhered cells in the tumor interior, resulting in reduced metastatic burden and delayed disease recurrence in vivo. This work confirms septin-mediated bleb signaling as a previously unrecognized vulnerability of disseminated cancer cells and demonstrates that this morphology-encoded pathway operates in vivo to support disease progression, preserving cancer cell viability under conditions in which cell survival signals from the environment are muted. These findings suggest novel opportunities to target survival signaling in micrometastatic disseminated cancer cells. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=150 SRC="FIGDIR/small/697601v1_ufig1.gif" ALT="Figure 1"> View larger version (61K): org.highwire.dtl.DTLVardef@1770384org.highwire.dtl.DTLVardef@87e567org.highwire.dtl.DTLVardef@1e5d6b2org.highwire.dtl.DTLVardef@724c5f_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

A Complexity-Science Framework for Studying Flow: Using Media to Probe Brain-Phenomenology Dynamics

Consciousness spans a range of phenomenological experiences, from effortless immersion to disengaged monotony, yet how such phenomenology emerges from brain activity is not well understood. Flow, a phenomenological experience frequently elicited by interactive media, has drawn attention for its links to performance and wellbeing, but existing neural accounts rely on single region or small network analyses that overlook the brains distributed and dynamic nature. Complexity science offers tools that capture brain-wide dynamics, but this approach has rarely been applied to flow or to its natural comparisons: boredom and frustration. Consequently, it remains unclear whether tools drawn from complexity science can objectively discriminate between these phenomenological experiences while also clarifying their neural basis. To address this uncertainty, we induced each phenomenological experience with a difficulty-titrated video game during functional magnetic resonance imaging and collected concurrent behavioral and self-report data. Our complex systems analyses revealed that flow, in this experimental setup, shows an inverse relationship to global entropy with moderate explanatory power, and is not explained by either synchronization or metastability, whereas boredom and frustration exhibit different configurations of brain-dynamics metrics. Notably, these findings integrate previously separate prefrontal and network-synchrony observations within a single dynamical systems framework and identify complexity-based markers with the potential to map the neural underpinnings of media-related benefits.

neuroscience↗

Using Y-chromosome capture enrichment to resolve haplogroup H2 shows new evidence for a two-Path Neolithic expansion to Western Europe

Uniparentally-inherited markers on mitochondrial DNA (mtDNA) and the non-recombining regions of the Y chromosome (NRY), have been used for the past 30 years to investigate the history of humans from a maternal and paternal perspective. Researchers have preferred mtDNA due to its abundance in the cells, and comparatively high substitution rate. Conversely, the NRY is less susceptible to back mutations and saturation, and is potentially more informative than mtDNA owing to its longer sequence length. However, due to comparatively poor NRY coverage via shotgun sequencing, and the relatively low and biased representation of Y-chromosome variants on capture arrays such as the 1240K, ancient DNA studies often fail to utilize the unique perspective that the NRY can yield. Here we introduce a new DNA enrichment assay, coined YMCA (Y-mappable capture assay), that targets the "mappable" regions of the NRY. We show that compared to low-coverage shotgun sequencing and 1240K capture, YMCA significantly improves the coverage and number of sites hit on the NRY, increasing the number of Y-haplogroup informative SNPs, and allowing for the identification of previously undiscovered variants. To illustrate the power of YMCA, we show that the analysis of ancient Y-chromosome lineages can help to resolve Y-chromosomal haplogroups. As a case study, we focus on H2, a haplogroup associated with a critical event in European human history: the Neolithic transition. By disentangling the evolutionary history of this haplogroup, we further elucidate the two separate paths by which early farmers expanded from Anatolia and the Near East to western Europe.

genetics↗

Nuclear envelope assembly defects link mitotic errors to chromothripsis

Defects in the architecture or integrity of the nuclear envelope (NE) are associated with a variety of human diseases1. Micronuclei, one common nuclear aberration, are an origin for chromothripsis2,3, a catastrophic mutational process commonly observed in cancer genomes and other contexts4-6. Micronuclei have a defective NE, with the extensive chromosome fragmentation that generates chromothripsis occurring after abrupt, spontaneous loss of NE integrity7. After NE disruption, the exposed cytoplasmic DNA can additionally initiate proinflammatory signaling linked to senescence, metastasis, and the immune clearance of tumor cells8. Despite its broad physiological impact, the basis for the nuclear envelope fragility of micronuclei is unknown. Here we demonstrate that micronuclei undergo markedly defective NE assembly: Only \"core\" NE proteins9,10 assemble efficiently on lagging chromosomes whereas \"non-core\" NE proteins9,10, including nuclear pore complexes (NPCs), fail to properly assemble. Consequently, micronuclei have impaired nuclear import, and key nuclear proteins required to maintain the integrity of the NE and the genome fail to accumulate normally. We show that densely bundled spindle microtubules inhibit non-core NE assembly, leading to an irreversible NE assembly defect. Accordingly, experimental manipulations that position missegregated chromosomes away from the spindle correct defective NE assembly, prevent spontaneous NE disruption, and suppress DNA damage in micronuclei. Our findings indicate that chromosome segregation and NE assembly are only loosely coordinated through the timing of mitotic spindle disassembly. The absence of precise regulatory controls can explain why errors during mitotic exit are frequent, and a major trigger for catastrophic genome rearrangements5,6.

cell biology↗