Table 1.

Summary of clinical and biological studies that investigated the role of CD26 expression in different types of cancer.

Reference	Disease	CD26 Expression	Effect of CD26
[13]	Melanoma	Overexpression	Tumor suppressor
[14,15,16]	NSCLC	Overexpression	Tumor suppressor/ Tumor promoter
[17,18,19,20,21,22]	Colon cancer MPM	Reduction Overexpression	Tumor promoter
[23,24,25]	Breast cancer	Heterogeneous expression	Tumor suppressor

Abbreviations: NSCLC, non-small cell lung cancer; MPM, malignant pleural mesothelioma.