Regucalcin Is a Potential Regulator in Human Cancer: Aiming to Expand into Cancer Therapy

Abstract

Regucalcin, a calcium-binding protein lacking the EF-hand motif, was initially discovered in 1978. Its name is indicative of its function in calcium signaling regulation. The rgn gene encodes for regucalcin and is situated on the X chromosome in both humans and vertebrates. Regucalcin regulates pivotal enzymes involved in signal transduction and has an inhibitory function, which includes protein kinases, protein phosphatases, cysteinyl protease, nitric oxide dynthetase, aminoacyl-transfer ribonucleic acid (tRNA) synthetase, and protein synthesis. This cytoplasmic protein is transported to the nucleus where it regulates deoxyribonucleic acid and RNA synthesis as well as gene expression. Overexpression of regucalcin inhibits proliferation in both normal and cancer cells in vitro, independent of apoptosis. During liver regeneration in vivo, endogenous regucalcin suppresses cell growth when overexpressed. Regucalcin mRNA and protein expressions are significantly downregulated in tumor tissues of patients with various types of cancers. Patients exhibiting upregulated regucalcin in tumor tissue have shown prolonged survival. The decrease of regucalcin expression is linked to the advancement of cancer. Overexpression of regucalcin carries the potential for preventing and treating carcinogenesis. Additionally, extracellular regucalcin has displayed control over various types of human cancer cells. Regucalcin may hold a prominent role as a regulatory factor in cancer development. Supplying the regucalcin gene could prove to be a valuable asset in cancer treatment. The therapeutic value of regucalcin suggests its potential significance in treating cancer patients. This review delves into the most recent research on the regulatory role of regucalcin in human cancer development, providing a novel approach for treatment.

Exploring the Molecular Tapestry: Organ-Specific Peptide and Protein Ultrafiltrates and Their Role in Therapeutics

“…FABPs are a family of small, highly conserved, cytoplasmic proteins that bind long-chain fatty acids to facilitate movement across extracellular and intracellular membranes and other hydrophobic ligands [ 23 ]. These proteins are believed to transfer lipophilic substances such as eicosanoids and retinoids from the outside cell membrane to specific intracellular receptors, such as PPA receptors (PPAR), a group of nuclear receptor proteins [ 23 ].…”

“…FABPs are a family of small, highly conserved, cytoplasmic proteins that bind long-chain fatty acids to facilitate movement across extracellular and intracellular membranes and other hydrophobic ligands [ 23 ]. These proteins are believed to transfer lipophilic substances such as eicosanoids and retinoids from the outside cell membrane to specific intracellular receptors, such as PPA receptors (PPAR), a group of nuclear receptor proteins [ 23 ]. By binding to PPAR-responsive regulatory elements as obligate heterodimers with retinoid X receptor (RXR), the PPARs control the expression of networks of genes involved in energy production, lipid metabolism, and inflammation [ 24 , 25 ].…”

“…Regucalcin was noted for its potential protective effect against age-related diseases. It has also been studied for its anti-cancer properties, which could be how this protein is used [ 23 ].…”

Logistic PCA explains differences between genome-scale metabolic models in terms of metabolic pathways

“…Besides its metabolic role, RGN is involved in calcium homeostasis, antioxidant defense, apoptosis, and cell proliferation [43]. Recently, RGN has been identified to be downregulated in several cancer cells [44] and that survival of cancer patients is positively correlated with a higher expression level of RGN [45].…”