Purpose: The identification of novel molecular biomarkers may assist in the characterization of indeterminate thyroid nodules, which pose significant diagnostic challenges. Here, we aimed to explore the potential of proteomic analyses to support biomarker discovery in challenging thyroid lesions. Methods: Linear Discriminant Analysis (LDA) was applied to Matrix-Assisted Laser Desorption Ionization Mass Spectrometry Imaging (MALDI-MSI) data from 44 thyroid neoplasms to select the most impactful molecular features for the classification of different tumor histologies, as well as for the distinction between NRAS-mutant (mNRAS) and NRAS-wild-type (wtNRAS) tumors. Relevant peaks were subsequently identified through nanoscale liquid chromatography electrospray ionization tandem mass spectrometry (nLC–ESI-MS/MS). Results: The LDA selected nine relevant molecular markers distinguishing noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTPs) from other tumor histologies (balanced accuracy = 73%), as well as 19 relevant markers able to identify mNRAS cases (balanced accuracy = 84%). Nine differentially expressed proteins were putatively identified: among them, ATP-dependent RNA helicase DDX42 showed a similar distribution between NIFTPs and papillary thyroid carcinomas (PTCs) / follicular variant PTCs (FVPTCs), while the distribution of the Histone H4 signal was similar between NIFTPs and follicular adenomas (FAs). In addition, Protein disulfide-isomerase A1 and Complement C4-B were overexpressed in wtNRAS compared to mNRAS cases, regardless of histology. Conclusion: The LDA-selected features enable to distinguish NIFTPs from morphologically similar lesions and to discriminate between mNRAS and wtNRAS cases. The identified markers might complement genetic analyses and provide insights into the distinct pathogenic drivers behind the development of mNRAS compared to wtNRAS lesions.

Follicular-patterned thyroid neoplasms comprise a diverse group of lesions that pose significant challenges in terms of differential diagnosis based solely on morphologic and genetic features. Thus, the identification of easily testable biomarkers complementing microscopic and genetic analyses is a highly anticipated advancement that could improve diagnostic accuracy, particularly for noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTPs). These tumors exhibit considerable morphological and molecular heterogeneity, which may complicate their distinction from structurally similar neoplasms, especially when genetic analyses reveal shared genomic alterations (e.g., RAS mutations). Here, we integrated next-generation sequencing (NGS) with matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to perform a proteogenomic analysis on 85 NIFTPs (n = 30 RAS-mutant [RAS-mut] and n = 55 RAS-wild type [RAS-wt]), with the aim to detect putative biomarkers of RAS-mut lesions. Through this combined approach, we identified four proteins that were significantly underexpressed in RAS-mut as compared to RAS-wt NIFTPs. These proteins could serve as readily accessible markers in morphologically borderline cases showing RAS mutations. Additionally, our findings may provide insights into the distinct pathogenic pathways through which RAS-mut and RAS-wt NIFTPs arise, highlighting the pivotal role of constitutive RAS–mitogen-activated protein kinase (MAPK) pathway activation in the development and progression of RAS-mut tumors.

Sweet’s syndrome (SS) is a rare neutrophilic dermatosis often associated with hematologic malignancies. Due to its infectious mimicry, diagnosis is frequently delayed. We report a case of primary myelofibrosis initially treated for suspected cellulitis, which progressed to necrotic lesions and refractory fever despite broad‐spectrum antibiotics. A skin biopsy confirmed neutrophilic vasculitis consistent with SS. Prompt treatment with corticosteroids followed by ruxolitinib achieved rapid resolution by suppressing the underlying cytokine storm.

Chimeric Antigen Receptor (CAR) therapy for Acute Myeloid Leukemia (AML) is hindered by disease heterogeneity, antigen overlap with normal hematopoiesis, and the persistence of leukemic stem cells (LSCs). To overcome these barriers, we employed the IF-BETTER strategy to simultaneously target CD33 and the LSC-associated marker TIM-3 by pairing a second-generation CAR with a Cytokine-Costimulatory Receptor (CCR) in two dual CAR configurations (CD33.CAR/TIM-3.CCR and TIM-3.CAR/CD33.CCR). Both constructs displayed potent antigen-restricted cytotoxicity against AML cell lines and primary blasts, achieving leukemia clearance, while sparing normal immune and hematopoietic cells. Mechanistic studies revealed that the TIM-3.CAR single-chain fragment variable (scFv) recognizes a protein-proximal epitope whose interaction is selectively enhanced by AML-specific hyper-fucosylated and hyper-sialylated N-glycans. Fucosylation blockade reduced TIM-3.CAR avidity and cytotoxicity, confirming a glycosylation-modulated interaction. Integrating this glycosylation-tolerant TIM-3 scFv into a dual CAR framework enables selective targeting of AML cells, providing a rational strategy for safer and more effective AML-directed immunotherapy.