CNDP2

CNDP2 Full Name

CNDP dipeptidase 2 (metallopeptidase M20 family)

CNDP2 Introduction

CNDP dipeptidase 2 (CNDP2), also referred to as cytosolic non-specific dipeptidase or carnosine dipeptidase 2, is a member of the M20 metallopeptidase family. Encoded by the CNDP2 gene on chromosome 18q22.3, CNDP2 is a homodimeric zinc-dependent enzyme that catalyzes the hydrolysis of a broad range of dipeptides, functioning preferentially as a non-specific dipeptidase in the cytosol. Unlike its homolog CNDP1 (serum carnosinase), which is secreted and exhibits narrow substrate specificity for carnosine and homocarnosine, CNDP2 displays broad substrate tolerance and serves a general role in dipeptide metabolism and amino acid recycling.

Figure 1. Strcuture of Protein CNDP2.

Enzymatic Mechanism and Metabolic Functions
CNDP2 is a homodimeric metalloprotease with each subunit containing a catalytic binuclear zinc center essential for hydrolytic activity. The enzyme cleaves dipeptides with diverse amino acid compositions, generating free amino acids that can be reutilized for protein synthesis or further catabolized for energy production. CNDP2 plays a significant role in the intracellular degradation of dipeptides generated during protein turnover, functioning downstream of the ubiquitin-proteasome system and autophagy pathways. Notably, CNDP2 contributes to the regulation of intracellular carnosine levels, a dipeptide with antioxidant and anti-glycation properties. In tissues with high metabolic demand such as skeletal muscle and brain, CNDP2-mediated dipeptide hydrolysis supports amino acid homeostasis and energy metabolism.

Clinical Significance in Cancer and Metabolic Disease
CNDP2 has been identified as a potential biomarker and functional contributor in several cancers. In hepatocellular carcinoma, CNDP2 is highly expressed and promotes tumor cell proliferation through the PI3K/AKT/mTOR signaling pathway; its knockdown suppresses tumor growth and enhances chemosensitivity to sorafenib. Conversely, in gastric cancer and breast cancer, CNDP2 overexpression has been correlated with favorable prognosis, suggesting context-dependent roles. Beyond oncology, CNDP2 polymorphisms have been associated with diabetic nephropathy susceptibility, potentially through altered carnosine metabolism and impaired protection against advanced glycation end products (AGEs). The emerging data position CNDP2 as a multifaceted enzyme with roles spanning cancer biology, metabolic disease, and amino acid homeostasis.

Alternate Names for CNDP2

CNDP2; CNDP dipeptidase 2 (metallopeptidase M20 family); PEPA, peptidase A; cytosolic non-specific dipeptidase; CN2; CPGL; cytosolic nonspecific dipeptidase (EC 3.4.13.18); FLJ10830; HsT2298; peptidase A; cytosolic nonspecific dipeptidase; glutamate carboxypeptidase-like protein 1; PEPA; FLJ35544;