In Vitro Selection of Cancer Cell-Specific Molecular Recognition Elements from Amino Acid Libraries

Table 1

Types of amino acid libraries.

Library type	Advantages	Cell SELEX examples
Peptide	(i) Well-studied; (ii) Widely available libraries	(i) B-cell lymphoma [89]; (ii) Chronic lymphocytic leukemia [83]; (iii) Non-small cell lung cancer [90]; (iv) Breast cancer cell lines BT-474 & SKBR-3 [91, 92]; (v) Follicular thyroid carcinoma [93]; (vi) Colorectal tumor cell lines [73, 94]; (vii) Metastatic prostate cancer cells [95, 96]
Antibody fragment	(i) Antibody structure and diversity selectable in vitro; (ii) Final product can be made into a full antibody; (iii) Pharmacological profile similar to antibodies which are clinically available	(i) Prostate cancer cell lines [98, 99]; (ii) Melanoma [100]; (iii) Hepatocellular carcinoma [101]; (iv) Breast cancer tissue [102]; (v) Tumor T cells [103]; (vi) Ovarian carcinoma [104]

In general, advantages of both types of library include in vivo stability and the diversity and structure of 20 amino acids.