Elleine Allapitan

Background: Adolescent and young adult (AYA; 13 to 39 years) survivors of childhood cancer may be especially vulnerable to physical health and mental health concerns during the pandemic. We investigated the impact of COVID-19 on the mental health status of AYA survivors (Aim 1) and shared tailored, evidence-based health-related information on COVID-19 (Aim 2). Methods: Between May and June 2020, participants completed a cross-sectional online survey assessing their cancer history, current mental health status, and their COVID-19 information needs. Results: Ninety-four participants (78 females, 13 males, 2 non-binary) with a mean age of 26.9 years (SD = 6.2) were included in the final sample. Participants reported residing from 10 countries and 94% identified as White. Nearly half of the participants (49%) described their mental health status as worse now than before the pandemic. Thirty-nine participants (41%) that indicated their current mental health status was tied to fears/worries about their past cancer and treatment experienced a higher level of anxiety and PTSS than those who did not report the same. Most participants (77%) had not received any information related to the potential risks of COVID-19 and expressed an interest in receiving this information. In response, an infographic detailing recommended strategies for coping with mental health problems in the pandemic, along with preliminary study findings, was developed. Discussion: AYA survivors reporting their mental health status was linked to their past cancer experienced poorer mental health. There is a value to educating survivors on their potential health risks, but accounting for their perceived mental health vulnerabilities should be considered when disseminating knowledge. The use of an infographic is a unique contribution towards the development of innovative and personalized means of sharing health education to this vulnerable yet resilient group. This research on the mental health status of AYA survivors very early in the pandemic informs continued initiatives investigating the rapidly changing nature of how COVID-19 may impact AYA survivors today and in the future.

Abstract Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, with treatment failure largely driven by cancer stem-like cells that resist conventional chemoradiation and subsequently initiate tumor recurrence. While immune checkpoint blockade is effective in microsatellite instability-high (MSI-H) CRCs, the majority of CRCs are microsatellite stable (MSS) and exhibit immune exclusion, rendering them refractory to immunotherapy. Here, we identify a previously uncharacterized cancer cell subtype, which we term cancerous Crypt Base Columnar (canCBC) cells. These cells transcriptionally resemble normal LGR5+ CBC cells but activate an aberrant WNT/β-catenin signalling inhibitory program, marked by NOTUM expression. We show that canCBC cells are specifically enriched in MSS tumors, where their presence correlates with reduced CD8⁺ T cell infiltration, broader immune exclusion, and a propensity for regional lymphatic dissemination. Consistently, targeted ablation of canCBCs enhances the tumor-clearing potential of CD8⁺ T cells. This study identifies a novel therapeutic target for overcoming immune exclusion and improving immunotherapy responses in MSS CRCs.

Gastric cancer is marked by profound molecular and microenvironmental heterogeneity that limits therapeutic progress. Here, we present a 15-layer multi-omics atlas that integrates genomics, epigenomics, transcriptomics, proteomics, multiple post-translational modifications (PTMs), protein-protein interactions, metabolomics, and microbiome profiles from 159 primary gastric adenocarcinomas and 30 matched normal adjacent tissues. Using cell-state deconvolution, we define tumor ecotypes that refine genomic and histological subtypes by capturing distinct tumor microenvironment architectures linked to clinical outcomes and potential associations with immunotherapy response. Multi-omics integration prioritizes genomic and epigenomic aberrations and their associated vulnerabilities; defines ecotype-specific transcriptional programs, signaling pathways, PTMs, protein interaction networks, and metabolic regulation; and identifies microbiome features linked to ecotypes and resistance pathways. We further prioritize ecotype-, genomic subtype-, and cell type-specific targetable proteins using proteomic and PTM analyses within a tumor microenvironment context. This comprehensive atlas provides a systems-level blueprint for decoding gastric cancer heterogeneity and advancing precision oncology.