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Biology subjects

Kameneva, P.

Publications and source records attributed to Kameneva, P..

5 recordsLinked to original sources

A human lung organoid co-culture model of early bone sarcoma metastasis reveals contact-dependent epithelial remodeling at the metastatic interface

Lung metastasis drives mortality across cancer types, yet how infiltrating tumor cells remodel the lung epithelium to establish metastatic niches remains poorly understood. Here we establish MESCUL (MEtastatic Sarcoma Co-CULture), a co-culture platform combining human lung organoids with patient-derived bone sarcoma cells to model early tumor-lung epithelial interactions in a physiologically relevant 3D system. MESCUL reveals that direct tumor-epithelial contact induces rapid, reproducible lung epithelial remodeling across Ewing sarcoma (ES) and osteosarcoma (OS) models and multiple organoid donor backgrounds, which is contact-dependent and not recapitulated by paracrine signaling. Single-cell RNA sequencing identifies LIMES (Lung Interface Metastasis Signature), a shared transcriptional program encompassing focal adhesion assembly, matrix metalloprotease (MMP) upregulation, and emergence of a damage-associated transitional cell state, in both ES and OS. Mechanistically, tumor-derived fibronectin (FN1) engages epithelial integrin receptors to activate focal adhesion kinase (FAK), driving amphiregulin (AREG) induction and MMP-mediated remodeling; FN1 alone phenocopies this response, and FAK inhibition attenuates it, nominating the FN1-integrin-FAK-AREG axis as a candidate therapeutic vulnerability. The LIMES program, identified through the MESCUL co-culture model, is spatially confined to the tumor-lung interface in patient metastases of both ES and OS, as demonstrated by spatial transcriptomics across nine patients. Massons trichrome staining of matched patient sections reveals pronounced collagen deposition in the peri-tumoral lung parenchyma, consistent with LIMES acting upstream of a wound-healing cascade that proceeds to structural fibrotic remodeling in patient tissue. Together, these findings establish the lung epithelium as an active participant in metastatic colonization, characterize a pharmacologically targetable, spatially restricted epithelial remodeling response at the bone sarcoma-lung interface across OS and ES, and introduce MESCUL as a tractable 3D platform for investigating lung metastasis, with possible implications for tumor types beyond bone sarcomas.

cancer biology↗

Single-cell, clonal and spatial atlases of cranial placodes illuminate their specification and evolution

The vertebrate head is defined by complex sensory structures derived from cranial placodes. Placodes arise alongside the neural crest at the neural plate border, yet the mechanisms governing their identity, diversification, and evolutionary origins are unclear. We present an integrated single-cell, spatial, and clonal atlas of placode development to resolve the dynamics of their lineage segregation. Combining single-cell RNA-sequencing, spatial transcriptomics, and high-resolution clonal tracing, we show that placodal and neighboring progenitors form a continuous transcriptional landscape with gradual transitions between domains. Domain boundary cells co-express markers of adjacent territories, suggesting transient bipotent states. Consistent with this, clonal analysis reveals sharing of progenitors between neighboring placodes, supporting a model of competitive segregation. Comparisons with amphioxus suggests that vertebrate olfactory placodes emerged from an ancestral neuroectoderm that later partitioned into distinct neural and olfactory domains. Our findings provide a unified framework for understanding the developmental and evolutionary origins of vertebrate sensory organs.

developmental biology↗

High-resolution retrospective single cell lineage tracing with mutable homopolymers

Retrospective reconstruction of cell lineages from somatic mutations holds substantial promise for understanding development, tissue homeostasis, and disease. Yet, current approaches are often constrained by low marker density, technical noise, and incomplete molecular readouts that limit the resolution and accuracy of inferred lineages. Here, we present RETrace2, a single-cell dual-omic method for simultaneous lineage tracing and cell-type identification. By identifying and targeting highly mutable homopolymers, which we show are approximately twice as informative as conventional microsatellite repeats, combined with technical improvements to increase marker coverage and reduce experimental errors of reading and amplifying homopolymers, RETrace2 can trace lineage continuously at an estimated resolution of fewer than five cell divisions in microsatellite-unstable organisms. Simultaneously, sparse methylation profiles were obtained from the same cells for cell-type identification. We validated the method using in vitro ground-truth models and demonstrated its utility in vivo by reconstructing multi-organ lineage trees from the brain, kidney and liver of Msh2-deficient mice.

genetics↗

Developmental heterogeneity of embryonic neuroendocrine chromaffin cells and their maturation dynamics

During embryonic development, nerve-associated Schwann cell precursors (SCPs) give rise to chromaffin cells of the adrenal gland via the "bridge" transient stage, according to recent functional experiments and single cell transcriptomics data from humans and mice. However, currently existing data do not resolve the finest heterogeneity of developing chromaffin populations. Here we took advantage of deep SmartSeq2 transcriptomics sequencing to expand our collection of individual cells from developing murine sympatho-adrenal anlage and uncover the microheterogeneity of embryonic chromaffin cells and corresponding developmental paths. After improving our atlas of sympatho-adrenal development and performing experimental validations, we discovered that SCPs in the local nerve show high degree of microheterogeneity corresponding to early biases towards either Schwann or chromaffin terminal fates. Furthermore, we found that a post-"bridge" population of developing chromaffin cells gives rise to persisting immature chromaffin cells and the two terminal populations (adrenergic and noradrenergic) via diverging differentiation paths. Taken together, we provide a thorough identification of novel markers of adrenergic and noradrenergic populations in developing adrenal glands and report novel differentiation micro-paths leading to them.

developmental biology↗

Malignant Schwann cell precursors mediate intratumoral plasticity in human neuroblastoma

Neuroblastoma is a heterogeneous embryonal malignancy and the most deadly tumor of childhood, although a minor subset may show spontaneous differentiation. It arises from the multipotent neural crest lineage during development. Some of this multipotency is retained in neuroblastoma, which can give rise to both adrenergic and mesenchymal tumor cells. The mechanisms enabling such dual fates are unknown, but likely help neuroblastoma to evade existing therapies. To understand neuroblastoma plasticity, we analyzed patient tumors using single-cell transcriptomics. In addition to the heterogeneous adrenergic and mesenchymal populations, we identify a subpopulation of malignant cells resembling Schwann cell precursors (SCPs). This SCP-like population connects the adrenergic and mesenchymal compartments through transitions structurally reminiscent of the SCP cell-fate decision fork that occurs during normal development. While the directionality of such transitions in neuroblastoma remains to be established, this finding expands the potential reservoirs of malignant cells, and suggests intratumoral plasticity mechanisms relevant for therapeutic resistance and relapse.

cancer biology↗