Molecular recognition undoubtedly governs any aspect ofcellular interaction. To understand tumor cell growthregulation and spread, analysisof protein carbohydrateinteractions can contribute to lead to the establishment ofrational methods for diagnosis and therapy. Chemically andbiochemically optimized preparation of adequate tools, theirapplication for localization of receptor (tissue lectin) andligand (cellular glycoconjugate) pairs in tumor cells andtumor sections and the usefulness of a lectin from a plantextract as potent immunomodulator indicate the prospect fora place of such techniques in pathology and oncology.