Purpose: To uncover the underpinnings of acquired resistance (AR) to immunotherapy (IO), we determined whether distinctive clinicopathologic, radiomic, and peripheral blood (PB) immune-inflammatory features reflect oligo- and systemic (sys)-AR in patients with advanced non–small cell lung cancer (NSCLC) undergoing immune checkpoint inhibitor therapy. Experimental Design: On 105 consecutive patients with IO-treated advanced NSCLC, PB immunophenotypes, cytokines, and CT-derived radiomic features (RF), extracted from primary and merged metastatic lesions, were prospectively collected at baseline (T0) and at the first disease assessment (T1, 9–12 weeks), and their Δ variation [(T1−T0)/T0] was computed. AR, defined as progression after the initial response (complete/partial) or stable disease ≥6 months, was subdivided according to the number of new and/or progressive lesions in oligoAR (≤3) and sysAR (>3). Clinicopathologic, PB, and radiomic parameters and survival outcomes were statistically correlated to AR patterns. Results: OligoAR and sysAR involved 24% and 12.4% of cases, respectively. Whereas baseline PB immune profiles were comparable, a Δpos cytotoxic (NK, CD8+granzyme B+) and Δneg immunosuppressive (CD14+ monocytes) dynamic coupled with different modulations of IL-6, TGF-β1, TNFα, and soluble PD-L1 represented distinctive features of oligoAR versus sysAR (P < 0.05). Significantly longer postprogression survival characterized oligoAR versus sysAR (median 20.3 vs. 5.6 months; HR, 0.22; P < 0.001). The number and sites of oligoAR involvement appeared to condition the blood immune background (P < 0.05) and survival. ΔRFs outperformed baseline RFs, with 15 ΔRFs sharply discriminating oligoAR from sysAR (P range: <0.001–0.04). ROC analysis confirmed the optimal performance of top-ranked ΔRFs (AUC range: 0.88–0.99). Conclusions: Longitudinal analysis of blood-immune hallmarks and radiomic descriptors may decipher distinct patterns of AR to IO in advanced patients with NSCLC. See related commentary by Jeng and Schoenfeld, p. 1381

Infantile hemangiomas (IHs) are benign vascular neoplasms of childhood (prevalence 5–10%) due to the abnormal proliferation of endothelial cells. IHs are characterized by a peculiar natural life cycle enclosing three phases: proliferative (≤12 months), involuting (≥13 months), and involuted (up to 4–7 years). The mechanisms underlying this neoplastic disease still remain uncovered. Twenty-seven IH tissue specimens (15 proliferative and 12 involuting) were subjected to hematoxylin and eosin staining and a panel of diagnostic markers by immunohistochemistry. WT1, nestin, CD133, and CD26 were also analyzed. Moreover, CD31^pos/CD26^pos proliferative hemangioma–derived endothelial cells (Hem-ECs) were freshly isolated, exposed to vildagliptin (a DPP-IV/CD26 inhibitor), and tested for cell survival and proliferation by MTT assay, FACS analysis, and Western blot assay. All IHs displayed positive CD31, GLUT1, WT1, and nestin immunostaining but were negative for D2-40. Increased endothelial cell proliferation in IH samples was documented by ki67 labeling. All endothelia of proliferative IHs were positive for CD26 (100%), while only 10 expressed CD133 (66.6%). Surprisingly, seven involuting IH samples (58.3%) exhibited coexisting proliferative and involuting aspects in the same hemangiomatous lesion. Importantly, proliferative areas were characterized by CD26 immunolabeling, at variance from involuting sites that were always CD26 negative. Finally, in vitro DPP-IV pharmacological inhibition by vildagliptin significantly reduced Hem-ECs proliferation through the modulation of ki67 and induced cell cycle arrest associated with the upregulation of p21 protein expression. Taken together, our findings suggest that CD26 might represent a reliable biomarker to detect proliferative sites and unveil non-regressive IHs after a 12-month life cycle.

Driver mutations in T-cell acute leukemia (T-ALL) rarely affect druggable kinases. However, these kinases can be aberrantly activated or repressed as secondary oncogenic events. Thus, integrating unbiased phosphoproteomics with genomic approaches may offer novel opportunities for target discovery and therapeutic interventions. In our study, we identified WNK1 as a potential target in T-ALL by pairing a list of vulnerable kinases with data from a phosphoproteomic screen of T-ALL cell lines. We subsequently validated WNK1 by loss-of-function-based studies and tested WNK inhibitors in several in vitro and in vivo T-ALL models and clinical T-ALL samples. We showed that therapeutic WNK1 repression promotes polyploidy, resulting in cell proliferation arrest, and morphometric changes, such as incomplete cell division or chromosome segregation through altered mitotic spindle assembly and abscission defects. Furthermore, we found that WNK1 is overexpressed in the TAL1/2-related subgroup, but not in normal thymus or lymph nodes, suggesting a potential translational area for clinical exploitation in poor-prognosis T-ALL carrying PTEN mutations and del(6q). Our work also reports a functional contribution of WNK1 in the leukemia establishment and progression. Structurally WNK1 is an atypical serine/threonine kinase that diverge from canonical kinases by lacking the conserved lysine in subdomain II, instead featuring a cysteine in subdomain I, which is critical for ATP-binding. This unusual structural configuration creates a distinct ATP-binding pocket with limited sequence similarity to conventional kinases, offering a unique opportunity to develop highly selective small-molecules. Targeting this atypical ATP-domain could thus provide a therapeutic advantage and broaden the treatment landscape for T-ALL.

Principal component analysis of CT technical parameters

Survival outcome of the overall study population

Supplementary Materials and Methods