Despite a characteristic indolent course, a substantial subset of follicular lymphoma (FL) patients has an early relapse with a poor outcome. Cells in the microenvironment may be a key contributor to treatment failure. We used a discovery and validation study design to identify microenvironmental determinants of early failure and then integrated these results into the FLIPI. In total, 496 newly diagnosed FL grade 1–3 A patients who were prospectively enrolled into the MER cohort from 2002 to 2012 were evaluated. Tissue microarrays were stained for CD4, CD8, FOXP3, CD32b, CD14, CD68, CD70, SIRP-α, TIM3, PD-1, and PD-L1. Early failure was defined as failing to achieve event-free survival at 24 months (EFS24) in immunochemotherapy-treated patients and EFS12 in all others. CyTOF and CODEX analysis were performed to characterize intratumoral immunophenotypes. Lack of intrafollicular CD4 expression was the only predictor of early failure that replicated with a pooled OR 2.37 (95%CI 1.48–3.79). We next developed a bio-clinical risk model (BioFLIPI), where lack of CD4 intrafollicular expression moved patients up one FLIPI risk group, adding a new fourth high-risk group. Compared with BioFLIPI score of 1, patients with a score of 2 (OR 2.17; 95% CI 1.08–4.69), 3 (OR 3.53; 95% CI 1.78–7.54), and 4 (OR 8.92; 95% CI 4.00–21.1) had increasing risk of early failure. The favorable intrafollicular CD4 T cells were identified as activated central memory T cells, whose prognostic value was independent from genetic features. In conclusion, lack of intrafollicular CD4 expression predicts early failure in FL and combined with FLIPI improves identification of high-risk patients; however, independent validation is warranted.

Purpose: Multiparametric MRI (mpMRI) has become an indispensable radiographic tool in diagnosing prostate cancer. However, mpMRI fails to visualize approximately 15% of clinically significant prostate cancer (csPCa). The molecular, cellular, and spatial underpinnings of such radiographic heterogeneity in csPCa are unclear. Experimental Design: We examined tumor tissues from clinically matched patients with mpMRI-invisible and mpMRI-visible csPCa who underwent radical prostatectomy. Multiplex immunofluorescence single-cell spatial imaging and gene expression profiling were performed. Artificial intelligence–based analytic algorithms were developed to examine the tumor ecosystem and integrate with corresponding transcriptomics. Results: More complex and compact epithelial tumor architectures were found in mpMRI-visible than in mpMRI-invisible prostate cancer tumors. In contrast, similar stromal patterns were detected between mpMRI-invisible prostate cancer and normal prostate tissues. Furthermore, quantification of immune cell composition and tumor-immune interactions demonstrated a lack of immune cell infiltration in the malignant but not in the adjacent nonmalignant tissue compartments, irrespective of mpMRI visibility. No significant difference in immune profiles was detected between mpMRI-visible and mpMRI-invisible prostate cancer within our patient cohort, whereas expression profiling identified a 24-gene stromal signature enriched in mpMRI-invisible prostate cancer. Prostate cancer with strong stromal signature exhibited a favorable survival outcome within The Cancer Genome Atlas prostate cancer cohort. Notably, five recurrences in the 8 mpMRI-visible patients with csPCa and no recurrence in the 8 clinically matched patients with mpMRI-invisible csPCa occurred during the 5-year follow-up post-prostatectomy. Conclusions: Our study identified distinct molecular, cellular, and structural characteristics associated with mpMRI-visible csPCa, whereas mpMRI-invisible tumors were similar to normal prostate tissue, likely contributing to mpMRI invisibility.

Morphological manifestations of acute colitis and subpopulation composition of colon lymphocytes were studied in male and female C57Bl/6 mice with acute dextran-induced colitis. We evaluated the severity of colitis symptoms, morphological changes in the colon, and prevalence of epithelialized and non-epithelialized ulcers. The subpopulation composition of lymphocytes (CD3-CD19 B cells, CD3CD4 T helpers, CD3CD8 cytotoxic T cells, and CD4CD25FOXP3 regulatory T cells) was assessed by flow cytofluorometry in suspension of colon cells prepared by enzymatic disintegration. In males, clinical manifestations of acute colitis and morphological changes were more severe and the prevalence of non-epithelialized ulcers was higher than in females. In females, the content of T, B, and regulatory T cells in the colon wall was higher, while the content of cytotoxic T cells was lower than in males. In females with acute colitis, the absolute lymphocyte count and the content of B cells and regulatory T cells decreased, while the percentage of cytotoxic T cells increased in comparison with intact animals. In males with acute colitis, the levels of regulatory T and B cells increased in comparison with the corresponding parameter in intact animals. Morphological changes and changes in the lymphocyte subpopulations, detected in males and females with acute colitis, were determined by different levels of sex steroid hormones.

Anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma is a rare large B-cell lymphoma subtype that is characterized by a plasmablastic phenotype and an ALK gene fusion. ALK-positive large B-cell lymphoma is resistant to the first-generation ALK inhibitor crizotinib and uniformly fatal with few if any complete responses in the relapsed setting, where no long-term survivors have been reported in the literature. No standard therapies exist for patients with relapsed or refractory disease, and its rarity and lethality have precluded prospective clinical research. Herein, we report the generation of the first ALK-positive large B-cell lymphoma patient-derived xenograft model, in which we show that next-generation ALK inhibitors are therapeutically active. On this basis, we administered the next-generation ALK inhibitor alectinib to four consecutive patients (three crizotinib-refractory). All four responded (two complete responses), one in ongoing remission after allogeneic transplantation >15 months. One with progressive disease was treated with lorlatinib and achieved complete response. These data support use of alectinib and lorlatinib as off-label therapeutic options for patients with relapsed or refractory ALK-positive large B-cell lymphoma.