Clin Chim Acta. 2026 Aug 25;593:121299. doi: 10.1016/j.cca.2026.121299. Online ahead of print.

ABSTRACT

Acute lymphoblastic leukemia (ALL) represents the most common malignancy diagnosed in children, accounting for approximately 25-30% of all pediatric cancers. Despite remarkable improvements in survival rates over recent decades, with cure rates exceeding 90% in developed countries, the diagnosis and monitoring of ALL continue to rely on invasive bone marrow aspiration and morphological assessment. MicroRNAs (miRNAs), small non-coding RNA molecules that regulate gene expression post-transcriptionally, have emerged as promising biomarkers for cancer diagnosis and prognosis due to their stability in biological fluids, tissue-specific expression patterns, and regulatory roles in oncogenesis. This comprehensive review systematically examines the current evidence regarding miRNA expression profiles in pediatric ALL, focusing on their diagnostic potential, prognostic value, and applicability as non-invasive biomarkers. Aberrant miRNA expression has been consistently demonstrated in pediatric ALL, with specific signatures distinguishing B-cell precursor ALL from T-cell ALL, identifying cytogenetic subtypes, and predicting treatment response. Circulating miRNAs, particularly those packaged within exosomes, offer non-invasive alternatives for minimal residual disease monitoring and early relapse detection. Machine learning approaches integrating multi-miRNA panels have achieved high diagnostic accuracy, with several miRNAs, including miR-128-3p, miR-181a, miR-196b, miR-200c, and miR-326, demonstrating significant clinical utility. MicroRNA profiling represents a transformative approach to pediatric ALL management, offering enhanced diagnostic precision, improved risk stratification, and non-invasive monitoring capabilities. While challenges remain in standardizing detection methodologies and establishing clinically validated thresholds, the integration of miRNA biomarkers into clinical practice holds substantial promise for personalized medicine in childhood leukemia.

PMID:42641935 | DOI:10.1016/j.cca.2026.121299

Clin Chim Acta. 2026 Mar 31;588:120992. doi: 10.1016/j.cca.2026.120992. Online ahead of print.

ABSTRACT

Bladder cancer diagnosis and surveillance remain anchored in cystoscopy and urine cytology, despite their invasiveness, operator dependence, and limited sensitivity for low-grade or flat lesions. These constraints have accelerated interest in liquid biopsy approaches that provide noninvasive, real-time molecular insights into tumor biology. This narrative review examines emerging evidence on three key classes of circulating biomarkers, namely, circulating tumor DNA (ctDNA), exosomes, and circulating tumor cells (CTCs), and their expanding roles in diagnosis, prognosis, and treatment guidance. ctDNA reflects tumor-specific genomic alterations and shows particular strength in detecting minimal residual disease, identifying early molecular relapse, and monitoring therapeutic response, although its diagnostic sensitivity remains moderate. Urinary exosomes demonstrate some of the highest diagnostic accuracies among liquid biopsy platforms, with multimarker RNA panels achieving sensitivities and specificities above 90%, while their diverse cargo of miRNAs, mRNAs, and lncRNAs provides robust prognostic information linked to recurrence and survival. CTCs, although technically challenging to isolate owing to their phenotypic heterogeneity, offer valuable insights into tumor aggressiveness, metastatic potential, and treatment responsiveness, especially in muscle-invasive disease. Advances in ultrasensitive sequencing, microfluidic CTC capture, and multi-omics integration are accelerating clinical translation. Collectively, circulating biomarkers are poised to complement and, in selected contexts, transform bladder cancer management by enabling earlier detection, individualized risk stratification, and more precise therapeutic decision-making.

PMID:41933678 | DOI:10.1016/j.cca.2026.120992