Plasma Glutamic Acid Levels and Their Association with Cancer Progression

Introduction: Cancer remains a major global challenge characterized by uncontrolled cell proliferation and metabolic reprogramming. Cancer cells reconfigure their metabolic pathways to sustain rapid proliferation and meet elevated energy demands, with amino acid metabolism being a crucial component of cancer metabolism. Beyond the traditional somatic theory, emerging evidence supports the mitochondrial metabolic theory of cancer, which attributes disease progression to impaired oxidative phosphorylation and increased reliance on glutaminolysis. Aim: The study aims to evaluate the levels of glutamic acid in cancer patients and healthy control subjects. Study Design: This was a cross-sectional study design of cancer patients attending oncology clinic in the hospitals. Methodology: A total of 100 participants (50 cancer patients and 50 control healthy subjects) were recruited for the study from Rivers State University Teaching Hospital and University of Port Harcourt Teaching Hospital in Port Harcourt, Rivers State. The plasma concentration of glutamic acid was analyzed using glutamic acid colorimetric kits. Results: The mean plasma glutamic acid concentration in cancer (134.83 ± 14.66) subjects was higher compared to the healthy control subjects (101.82 ± 10.99), confirming increased glutaminolysis and alteration in metabolic pathways in cancer. The result obtained also shows a statistically significant difference in glutamic acid level across the various stages of cancer progression, with Stage IV having the highest (150.93 ± 12.54), followed by Stage III (134.25 ± 12.12) and then Stage I-II (124.52 ± 5.29). From the results, glutamic acid, a byproduct of glutamine metabolism, can be used as a biomarker for early cancer detection. Conclusion: There was a significant increase in glutamic acid in cancer patients compared to the control healthy subjects. Thus, indicating metabolic reprogramming in cancer leads to its progression.