Pina, Y. | Search bioRxiv

bioRxiv2026

A comparative dataset on population genetics, traits, and distributions for nineteen Caribbean tree species

Although genetic diversity is a fundamental component of biodiversity, we lack data for a majority of species, particularly in biodiversity hotspots such as tropical forests. We present a comparative genetic dataset of 19 tropical tree species (including one palm) from the Caribbean island of Puerto Rico and neighboring islands (Hispanola and the US Virgin Islands). Using a reduced-representation sequencing technique (SLAF-seq), we identified species-specific single-nucleotide polymorphism (SNP) datasets with 24,413 to 433,637 high-quality SNPs per species. The focal species represent a range of life-history and climate associations, which may be relevant to their genetic structure. Therefore, we also include complementary information on species functional traits (wood density, leaf thickness, specific leaf area, maximum height, and seed dry mass), as well as geographic distributions and climatic associations from species distribution models.

genetics↗

bioRxiv2023

Spatial transcriptomics analysis identifies a unique tumor-promoting function of the meningeal stroma in melanoma leptomeningeal disease

Leptomeningeal disease (LMD) remains a rapidly lethal complication for late-stage melanoma patients. The inaccessible nature of the disease site and lack of understanding of the biology of this unique metastatic site are major barriers to developing efficacious therapies for patients with melanoma LMD. Here, we characterize the tumor microenvironment of the leptomeningeal tissues and patient-matched extra-cranial metastatic sites using spatial transcriptomic analyses with in vitro and in vivo validation. We show the spatial landscape of melanoma LMD to be characterized by a lack of immune infiltration and instead exhibit a higher level of stromal involvement. We show that the tumor-stroma interactions at the leptomeninges activate pathways implicated in tumor-promoting signaling, mediated through upregulation of SERPINA3 at the tumor-stroma interface. Our functional experiments establish that the meningeal stroma is required for melanoma cells to survive in the CSF environment and that these interactions lead to a lack of MAPK inhibitor sensitivity in the tumor. We show that knocking down SERPINA3 or inhibiting the downstream IGR1R/PI3K/AKT axis results in re-sensitization of the tumor to MAPK-targeting therapy and tumor cell death in the leptomeningeal environment. Our data provides a spatial atlas of melanoma LMD, identifies the tumor-promoting role of meningeal stroma, and demonstrates a mechanism for overcoming microenvironment-mediated drug resistance unique to this metastatic site.

cancer biology↗