Beyond glyco-proteomics-Understanding the role of genetics in cancer biomarkers

Advancements in Electrochemical Biosensors for Comprehensive Glycosylation Assessment of Biotherapeutics

Proteins represent a significant portion of the global therapeutics market, surpassing hundreds of billions of dollars annually. Among the various post-translational modifications, glycosylation plays a crucial role in influencing protein structure, stability, and function. This modification is especially important in biotherapeutics, where the precise characterization of glycans is vital for ensuring product efficacy and safety. Although mass spectrometry-based techniques have become essential tools for glycomic analysis due to their high sensitivity and resolution, their complexity and lengthy processing times limit their practical application. In contrast, electrochemical methods provide a rapid, cost-effective, and sensitive alternative for glycosylation assessment, enabling the real-time analysis of glycan structures on biotherapeutic proteins. These electrochemical techniques, often used in conjunction with complementary methods, offer valuable insights into the glycosylation profiles of both isolated glycoproteins and intact cells. This review examines the latest advancements in electrochemical biosensors for glycosylation analysis, highlighting their potential in enhancing the characterization of biotherapeutics and advancing the field of precision medicine.

Methylated ctDNA Quantification: Noninvasive Approach to Monitoring Hepatocellular Carcinoma Burden

BACKGROUND

Noninvasive, precision monitoring of hepatocellular carcinoma (HCC) treatment efficacy would greatly facilitate personalized therapy and improve patient outcomes. We hypothesize that quantifying methylated circulating tumor DNA (ctDNA) can be used to effectively monitor HCC burden without the need for biopsy.

STUDY DESIGN

Blood samples were collected from 25 patients, 21 with HCC and 4 with benign liver masses, at various timepoints throughout the course of treatment at a high-volume academic medical center. Quantification of methylated ctDNA molecules assessed CpG sites on more than 550 preselected cancer-specific amplicons. The tumor methylation score (TMS) was calculated by measuring the difference between the amount of methylation in the plasma and buffy coat with a normal cutoff value of 120 or less.

RESULTS

Among 10 patients with surgical HCC (5 surgical resections and 5 liver transplants), TMS revealed a statistically significant, rapid postoperative decline in 9. One patient who had a persistently elevated TMS on postoperative day 1 was subsequently found to have had metastatic disease. Patients in the negative control cohort all had normal-range pre- and postoperative TMS. Preoperative TMS correlated moderately with tumor burden on pathology (Spearman r = 0.54) of surgical specimens. From 11 subjects undergoing systemic therapy or Y90 radioembolization, analysis of 16 time periods demonstrated that the change in TMS (ΔTMS) was better associated with tumor progression than the change in Δalpha-fetoprotein (area under the curve 0.800 and 0.783, respectively). A composite score combining ΔTMS and Δalpha-fetoprotein further improved performance for detecting tumor progression with an area under the curve of 0.892.

CONCLUSIONS

These findings indicate that ctDNA methylation scores can effectively evaluate changes in tumor burden without the need for tumor biopsy.