Citations

614 Background: A consensus interpretation of the IDEA colon cancer study results suggested that risk categories based on T/N stage grouping be used to guide decision-making for duration (3 vs 6 months) of adjuvant FOLFOX or CapeOX chemotherapy. Given the prognostic potential of immune biomarkers, we examined the immunoscore and individual T and B lymphocyte markers in low and high risk T/N subsets of stage III colon carcinoma patients (N=600) treated with adjuvant FOLFOX. Methods: Immunoscore (CD3+, CD8+) and individual T-cell and CD20+ B-cell immunostain densities in central tumor (CT) and invasive margin (IM) of FFPE sections were quantified by image analysis. A predetermined immunoscore categorization was used [high (2-4) vs low (0-1)]. Individual markers were analyzed by backwards selection wherein CD3+ IM was most robust for prognosis and an optimized cutoff was then determined. Associations with disease-free survival (DFS) were analyzed by multivariable Cox regression adjusting for age, T/N stage, sidedness, KRAS/BRAF, and DNA mismatch repair. Results: In low and high risk T/N patient subsets, the immunoscore and CD3+ IM were each significantly discriminant for prognosis. Among low risk (T1-3N1) patients, a high vs low immunoscore was associated with a 91% vs 77% 3-year DFS [HR 0.57, 95% confidence interval (CI) 0.34-0.95, adjusted (adj) P= 0.026]. Among high risk (T4 or N2) patients, a high vs low immunoscore was associated with a 68% vs 54% 3-year DFS (HR 0.64, 95% CI 0.42-0.98, Padj= 0.034]. Similarly, a high vs low intratumoral CD3+ density at the invasive margin (IM) was significantly associated with prognosis in low risk [HR 0.37, 95% CI 0.21- 0.66), Padj< 0.0003] and in high risk [HR 0.47, 95% CI, 0.27- 0.80), Padj< 0.0028] patient subsets. Conclusions: Immunoscore and CD3+ IM were shown to prognostically stratify FOLFOX-treated patients within both low and high risk T/N subsets. These data underscore limitations of the T/N risk classification for adjuvant treatment decisions in stage III patients, and demonstrate the ability of T-cell markers to enhance prognostication to guide clinical decision-making.

612 Background: mCRC is a heterogeneous disease leading to possible disparate responses among lesions in a single pt. This study assesses the heterogeneity of lesion responses and evaluates the prognostic value of LBR12 and its mortality risk discrimination beyond RECIST responses. Methods: Pts with ≥ 2 lesions and no new lesions at 12 weeks (wks) were eligible. For each pt, after 12 wks of Rx, each lesion was categorized as progressive disease (L-PD: ≥20% increase in the longest diameter [LD]), partial response (L-PR: ≥30% decrease in LD), or stable disease (L-SD: neither L-PD nor L-PR). LBR12 was defined, per patient, by the combination of lesion responses: homogeneous LBR12 (L-PD, L-SD, L-PR only) and heterogeneous LBR12 (mixture of L-PD/L-SD, L-PD/L-PR, L-SD/L-PR). LBR12 and overall survival (OS) were correlated using stratified multivariate Cox models after adjusting for age, gender, and ECOG PS. Results: Among 9,092 mCRCs (Rx: chemo alone 44%; chemo + VEGF inhibitor [VEGFi] 42%; chemo + EGFR inhibitor [EGFRi] 10%) from 16 1st-line studies. Median OS: 2.2 years. Per RECIST at 12 wks, CR 0%; PR 36.1%; SD 60.9%; PD 3.0%. Responses in 52% were heterogeneous (Table). VEGFi and EGFRi treated pts had the highest rate of L-SD/L-PR (45%) and L-PR only (22%) status, respectively. Median OS increased monotonically across pts with more L-PRs and fewer L-PDs (Table). Pts with L-SD/L-PR status, among which 51% had SD per RECIST, had longer OS than those with L-SD only status (HRadj.= .81, padj.< .0001), but shorter OS than those with L-PR only status (HRadj.= 1.46, padj.< .0001). Pts with L-PD/L-SD status, among which 71% were SD per RECIST, had shorter OS than those with L-SD only status (HRadj.= 2.22, padj.< .0001). These associations were consistent across treatment regimens. Conclusions: The lesion-based response captures the heterogeneity of within pt lesion responses and provides refinement in predicting outcome beyond RECIST response at 12 wks. [Table: see text]

Background: Irritable bowel syndrome (IBS) reduces quality of life and burdens healthcare systems. This study identified factors associated with frequent use of IBS diagnostic tests and procedures. Methods: Using a United States claims database (2001–2012), tests and procedures in IBS patients occurring in the 2-year study period (12 months before/following the first IBS diagnosis) were analyzed: endoscopy, GI transit testing, anorectal procedures, and radiologic imaging. Patients were classified based on test/procedure frequency (3+, 1–2, or 0). Multivariate logistic regression identified factors associated with more frequent tests/procedures. Results: Among 201,322 IBS patients, 41.7% had 3+ tests/procedures, 35.1% had 1–2, and 23.3% had 0. Patients with more tests/procedures were older [mean age 50.6 (3+ group), more likely to be female and had more comorbidities, including anxiety, depressive disorders, and somatization. Dyspepsia [odds ratio (95% confidence interval): 1.80 (1.72–1.87)], interstitial cystitis [1.60 (1.45–1.77)], gastroesophageal reflux disease [1.59 (1.55–1.63)], constipation [1.50 (1.45–1.54)], and dyspareunia [1.38 (1.25–1.52)] were significantly associated with more tests/procedures (3+ versus 1–2), while anxiety, depressive disorders, and somatization were not. Patients with more frequent specialist visits [emergency department (ED; 1.10 (1.09–1.11)) and gastroenterologists (1.26 (1.26–1.27))] or at least one GI-related ED visit or inpatient admission [1.95 (1.86–2.04) and 3.67 (3.48–3.87), respectively] were more likely to have more tests/procedures (all p < 0.05). Conclusions: Test frequency in patients with IBS is strongly associated with demographic and clinical characteristics, especially comorbid conditions related to IBS. Presence of common overlapping comorbid conditions should increase clinicians’ confidence in making the diagnosis of IBS, thus curtailing redundant testing and reducing healthcare costs.

INTRODUCTION The human cerebral cortex has undergone an extraordinary increase in size and complexity during mammalian evolution. Cortical cell lineages are specified in the embryo, and genetic and epidemiological evidence implicates early cortical development in the etiology of neuropsychiatric disorders such as autism spectrum disorder (ASD), intellectual disabilities, and schizophrenia. Most of the disease-implicated genomic variants are located outside of genes, and the interpretation of noncoding mutations is lagging behind owing to limited annotation of functional elements in the noncoding genome. RATIONALE We set out to discover gene-regulatory elements and chart their dynamic activity during prenatal human cortical development, focusing on enhancers, which carry most of the weight upon regulation of gene expression. We longitudinally modeled human brain development using human induced pluripotent stem cell (hiPSC)–derived cortical organoids and compared organoids to isogenic fetal brain tissue. RESULTS Fetal fibroblast–derived hiPSC lines were used to generate cortically patterned organoids and to compare oganoids’ epigenome and transcriptome to that of isogenic fetal brains and external datasets. Organoids model cortical development between 5 and 16 postconception weeks, thus enabling us to study transitions from cortical stem cells to progenitors to early neurons. The greatest changes occur at the transition from stem cells to progenitors. The regulatory landscape encompasses a total set of 96,375 enhancers linked to target genes, with 49,640 enhancers being active in organoids but not in mid-fetal brain, suggesting major roles in cortical neuron specification. Enhancers that gained activity in the human lineage are active in the earliest stages of organoid development, when they target genes that regulate the growth of radial glial cells. Parallel weighted gene coexpression network analysis (WGCNA) of transcriptome and enhancer activities defined a number of modules of coexpressed genes and coactive enhancers, following just six and four global temporal patterns that we refer to as supermodules, likely reflecting fundamental programs in embryonic and fetal brain. Correlations between gene expression and enhancer activity allowed stratifying enhancers into two categories: activating regulators (A-regs) and repressive regulators (R-regs). Several enhancer modules converged with gene modules, suggesting that coexpressed genes are regulated by enhancers with correlated patterns of activity. Furthermore, enhancers active in organoids and fetal brains were enriched for ASD de novo variants that disrupt binding sites of homeodomain, Hes1, NR4A2, Sox3, and NFIX transcription factors. CONCLUSION We validated hiPSC-derived cortical organoids as a suitable model system for studying gene regulation in human embryonic brain development, evolution, and disease. Our results suggest that organoids may reveal how noncoding mutations contribute to ASD etiology. Summary of the study, analyses, and main results. Data were generated for iPSC-derived human telencephalic organoids and isogenic fetal cortex. Organoids modeled embryonic and early fetal cortex and show a larger repertoire of enhancers. Enhancers could be divided into activators and repressors of gene expression. We derived networks of modules and supermodules with correlated gene and enhancer activities, some of which were implicated in autism spectrum disorders (ASD).

Intracellular delivery is a critical step in biological discoveries and has been widely utilized in biomedical research. A variety of molecular tools have been developed for cell-based gene therapies, including FDA approved CAR-T immunotherapy, iPSC, cell reprogramming and gene editing. Despite the inspiring results of these applications, intracellular delivery of foreign molecules including nucleic acids and proteins remains challenging. Efficient yet non-invasive delivery of biomolecules in a high-throughput manner has thus long fascinates the scientific community. As one of the most popular non-viral technologies for cell transfection, electroporation has gone through enormous development with the assist of nanotechnology and microfabrication. Emergence of miniatured electroporation system brought up many merits over the weakness of traditional electroporation system, including precise dose control and high cell viability. These new generation of electroporation systems are of considerable importance to expand the biological applications of intracellular delivery, bypassing the potential safety issue of viral vectors. In this review, we will go over the recent progresses in the electroporation-based intracellular delivery and several potential applications of cutting-edge research on the miniatured electroporation, including gene therapy, cellular reprogramming and intracellular probe.

Abstract Purpose: Colorectal cancers with deficient DNA mismatch repair (dMMR) are presumed to uniformly have dense lymphocytic infiltration that underlies their favorable prognosis and is critical to their responsiveness to immunotherapy, as compared with MMR-proficient (pMMR) tumors. We examined T-cell densities and their potential heterogeneity in a large cohort of dMMR tumors. Experimental Design: CD3+ and CD8+ T-cell densities were quantified at the invasive margin (IM) and tumor core (CT) in 561 stage III colon cancers (dMMR, n = 278; pMMR, n = 283) from a phase III adjuvant trial (N0147). Their association with overall survival (OS) was determined using multivariable Cox analysis. Results: Although CD3+ and CD8+ T-cell densities in the tumor microenvironment were higher in dMMR versus pMMR tumors overall, intertumoral heterogeneity in densities between tumors was significantly higher by 30% to 88% among dMMR versus pMMR cancers (P &lt; 0.0001 for all four T-cell subtypes [CD3+IM, CD3+CT, CD8+IM, CD8+CT]). A substantial proportion of dMMR tumors (26% to 35% depending on the T-cell subtype) exhibited T-cell densities as low as that in the bottom half of pMMR tumors. All four T-cell subtypes were prognostic in dMMR with CD3+IM being the most strongly prognostic. Low (vs. high) CD3+IM was independently associated with poorer OS among dMMR (HR, 4.76; 95% confidence interval, 1.43–15.87; P = 0.0019) and pMMR tumors (P = 0.0103). Conclusions: Tumor-infiltrating T-cell densities exhibited greater intertumoral heterogeneity among dMMR than pMMR colon cancers, with CD3+IM providing robust stratification of both dMMR and pMMR tumors for prognosis. Potentially, lower T-cell densities among dMMR tumors may contribute to immunotherapy resistance.