Biomedical subjects

Steven T Rosen

Publications and source records attributed to Steven T Rosen.

3 recordsLinked to original sources

PubMed2026

Gut Microbiome Composition Is Associated With Response to CD38 Antibody (Daratumumab) Treatment Among Relapsed Multiple Myeloma Patients.

INTRODUCTION: Growing data support interactions between host-gut microbes and treatment responses in multiple myeloma (MM), where a higher abundance of Eubacterium hallii in stool samples has been found among MM patients with negative minimal residual disease after induction therapy. Here, we evaluated changes in the gut microbiome associated with daratumumab (dara) based therapy in 40 MM patients, before and after therapy. PATIENTS AND METHODS: Patients with relapsed MM and prior autologous transplantation who had received 1 to 4 prior lines of therapy were eligible. Two stool samples were collected, one within 1 week prior to dara (predara) and one immediately after 4 doses of dara (postdara). Metagenomics sequencing was conducted. Microbiome taxonomic analyses were performed using MetaPhlAn4, and microbial functional pathway analyses were conducted using HUMAnN3.6. QIIME2 was used for compositional and statistical analyses. RESULTS: Of 40 participants enrolled, there were 5 nonresponders; 35 patients achieved partial response (PR) or better (responders). Among responders, 10 patients achieved complete remission (CR), and 25 patients achieved either very good partial response (VGPR) or PR. There were no statistically significant differences between overall pre and postdara gut microbiomes. Differential abundance analysis (ANCOM-BC) showed statistically significant (q ≤ 0.05) overgrowth of Alistipes finegoldii and Acidaminococcus intestini species in responders and Ruminococcus torques, Sellimonas intestinalis and Clostridium symbiosum in nonresponders. Compared to non-CR, CR samples showed enrichment of Faecalibacterium prausnitzii; non-CR samples were enriched in Segatella copri and Faecalimonas umbilicata. DISCUSSION/CONCLUSION: Our results suggest differences in species between clinical responders and nonresponders, but larger prospective studies are needed to confirm these results.

Clinical response↗

PubMed2026

Targeting the METTL1/m7G axis as a therapeutic strategy in myeloid leukemia.

N7-methylguanosine (m7G), a prevalent modification in transfer RNAs (tRNAs), is primarily catalyzed by the methyltransferase METTL1. Although growing evidence supports a role for METTL1 in various tumors, its therapeutic potential and precise function in leukemia stem cell (LSC) homeostasis remain largely unexplored. Here, we identify METTL1 as a key regulator of LSC self-renewal and homing within bone marrow (BM) microenvironment through catalyzing m7G formation on a specific tRNA, tRNAPheGAA, thereby promoting leukemogenesis. Mechanistically, METTL1 loss significantly reduces m7G abundance and steady-state levels of tRNAPheGAA, leading to translation suppression and degradation of transcripts enriched with tRNAPheGAA-related codons, such as hematopoietic cell kinase (HCK). Decreased HCK expression disrupts CXCR4 signaling, impairing LSC self-renewal and BM homing. Therapeutically, we characterized a small-molecule METTL1 inhibitor (M1i; NSC137443), through high-throughput screening. Pharmacological inhibition of METTL1 demonstrated potent antitumor efficacy by reducing tRNA m7G levels and disrupting the tRNAPheGAA/HCK/CXCR4 cascade. Notably, targeting METTL1 significantly reduces LSC frequency, delays leukemogenesis, and prolongs survival in multiple acute myeloid leukemia models. Together, our findings establish a previously unrecognized role for METTL1 and its target tRNAPheGAA in LSC homeostasis and provide compelling proof-of-concept evidence that METTL1 is a druggable epitranscriptomic target for antileukemia therapy.

Humans↗

PubMed2022

The International Consensus Classification of Mature Lymphoid Neoplasms: a report from the Clinical Advisory Committee.

Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.

Advisory Committees↗