Circulating IgG Fragments for Gastric Cancer and Esophageal Cancer

Area of Science:

• Oncology
• Immunology
• Biochemistry

Background:

• Gastric and esophageal cancers pose significant health challenges with a need for improved early detection methods.
• Current diagnostic approaches may not always identify these cancers in their early, most treatable stages.

Purpose of the Study:

• To investigate the potential of proteolytic fragments of immunoglobulin G (IgG-LysK) as a biomarker for gastric and esophageal cancers.
• To evaluate the diagnostic accuracy and clinical utility of IgG-LysK in cancer detection.

Main Methods:

• Serum samples from gastric cancer (n=68), esophageal cancer (n=43) patients, and healthy donors (n=20) were analyzed.
• Levels of IgG-LysK were measured, alongside hemostasis indicators (prothrombin time, fibrinogen, plasminogen, a2-antiplasmin, protein C) and total IgG.
• Receiver Operating Characteristic (ROC) analysis was employed to assess diagnostic performance.

Main Results:

• Median IgG-LysK levels were significantly higher in patients with esophageal and gastric cancer compared to healthy controls.
• ROC analysis demonstrated high sensitivity (91%) and specificity (85%) for esophageal cancer, and moderate sensitivity (68%) with high specificity (85%) for gastric cancer.
• False-negative results were associated with advanced cancer stages, metastases, lower total IgG, increased a2-antiplasmin, and shorter prothrombin times, suggesting altered blood homeostasis.

Conclusions:

• Circulating IgG-LysK levels increase in the early stages of gastric and esophageal cancers.
• IgG-LysK holds potential as an early detection biomarker for these cancers, especially when used in conjunction with other markers.
• Further research into the role of hemostasis in false-negative IgG-LysK results is warranted.