Current cancer diagnostic procedures have several challenges such as

1) need for a tumor biopsy which is difficult to obtain each time for therapeutic intervention

2) limited predictive value of molecular histopathological classifications and biomarkers, therefore patients end up being over or under-treated. Tissue biopsies are painful, time consuming, expensive, and very importantly associated with tumor heterogeneity which limiting the efficacy of targeted therapies and compromising treatment outcomes. Therefore, it is of high concern to develop alternatives non-invasive tools to avoid most of these problems and accurate prediction of the tumor progression to improve the selection of patients for right treatment.

Recent advances in lysosome biology have established the role of lysosome enzymes in the pathophysiology of cancer. Lysosomal enzymes degrade macromolecules, and increased circulating enzyme activity may be an important mechanism in tumor progression and metastasis. This makes lysosome a potential target for cancer diagnosis and treatment. In the current research proposal we would like to measure lysosome enzyme activity in plasma and leukocytes from cancer patients and normal controls for early diagnosis, patient stratification and prognosis.

Lysosomes role in cancer

Lysosomes are membrane-bound intracellular organelles that contain more than 50 hydrolases to degrade and recycle macromolecules. The lysosomal degradation pathway regulates a variety of cellular functions such as autophagy, endocytosis, and phagocytosis to maintain cellular homeostasis. Deregulation of lysosomal degradative pathway causes lysosomal storage disorders and cancers. Accumulating evidences reported that Lysosomal enzymes can induce tumor progression and apoptosis, therefore lysosomes are very interesting targets for cancer therapy and have important implications in cancer diagnosis and prognosis.