PD734 - LINKING CIRCULATING MIRNAS WITH BODY COMPOSITION PARAMETERS IN NEWLY DIAGNOSED BREAST CANCER PATIENTS

PD734

LINKING CIRCULATING MIRNAS WITH BODY COMPOSITION PARAMETERS IN NEWLY DIAGNOSED BREAST CANCER PATIENTS

S. Orlando¹, F. Tambaro^1,*, G. Imbimbo¹, C. Gallicchio¹, M. I. Amabile², M. Muscaritoli¹, A. Molfino^1,3

¹Department of Translational and Precision Medicine, ²Department of Surgical Sciences, ³Department of Interdisciplinary Studies on WellBeing, Health and Environmental Sustainability (BeSSA), Sapienza University of Rome, Rome, Italy

Rationale: Body composition alterations in women diagnosed with breast cancer (BC) are increasingly recognized as clinically relevant, particularly changes in skeletal muscle (SM) and adipose tissue (AT). As key regulators of SM and AT metabolism, microRNAs (miRNAs) are emerging as biomarkers of tumour-host interactions, although their pathophysiological roles remain unclear. This study aims to quantify the expression of circulating miRNAs in newly diagnosed BC patients (BCP) and to evaluate their association with body composition parameters.

Methods: Fasting blood samples were collected from BCP (n=46) and controls (C, n=16). Relative expression levels of miRNAs were assessed by RT-qPCR. Body composition parameters, including fat mass index (FMI, kg/m²) and fat-free mass index (FFMI, kg/m²), were estimated by bioelectrical impedance analysis. BCP were stratified according to FFMI levels into low (LMM) and high muscle mass (HMM) groups.

Results: Circulating levels of miR-21, -29a, and -29b were significantly upregulated in BCP vs C (p<0.05). According to BMI (kg/m²) categories, we observed an upregulation of miR-21, -29a, and miR-29b in BCP with BMI>25 vs C. Circulating levels of miR-133a were also upregulated in BCP with BMI>25 vs those with BMI<25 (p<0.05) and significantly downregulated in BCP with LMM compared to HMM. Moreover, the expression levels of miR-133a were lower in those patients with low muscularity and Luminal B+ subtype (p<0.05).

Conclusion: These preliminary data suggest that circulating miRNAs may reflect early SM alterations in newly diagnosed BCP and potential differences according to molecular subtype.

Disclosure of Interest: None declared