ECRG2 inhibits cancer cell migration, invasion and metastasis through the down-regulation of uPA/plasmin activity

Abstract

The esophageal cancer-related gene 2 (ECRG2) is a novel gene that shows sequence similarity to KAZAL-type serine protease inhibitor. In this study, the migration and invasion of PG cancer cells were inhibited by ectopic expression of ECRG2 in vitro, and metastases decreased after injecting PG/pcDNA3.1-ECRG2 cells into the tail veins of nude mice. Control mice were injected with PG/pcDNA3.1 cells. To test the hypothesis that ECRG2 interacts with proteases and inactivates extracellular matrix degradation, binding affinity and co-immunoprecipitation experiments were performed using serum-free conditioned medium. The results showed that ECRG2 bound to two species of urokinase-type plasminogen activator (uPA) with molecular weights of 55 and 33 kDa. Furthermore, analysis of the uPA/plasmin activity showed that expression of ECRG2 reduced proteolysis of the plasmin substrate D-Val-Phe-Lys-p-nitroanilide, which was seen by a decrease of absorbance at 405 nm. Taken together, these results suggested that ECRG2 inhibits aggressiveness of cancer cell, possibly through the down-regulation of uPA/plasmin activity.

Expression of esophageal cancer related gene 4 (ECRG4), a novel tumor suppressor gene, in esophageal cancer and its inhibitory effect on the tumor growth in vitro and in vivo

“…The ECRG4 soluble protein was used to produce polyclonal antibody in rabbit or for functional experiments. 10 Rabbit experiments were approved by the institutional review board of animal care of the Animal Center, Peking Union Medical College & Chinese Academy of Medical Sciences. …”

Suppression of hepatocarcinoma model in vitro and in vivo by ECRG2 delivery using adenoviral vector

“…ECRG2 has been cloned in 1998 by mRNA differential display by comparing the gene expression between normal esophageal epithelia and esophageal carcinoma 9 and further studies showed that it had roles as a tumor suppressor. [4][5][6]10 It was downregulated in esophageal squamous carcinoma and other cancers. ECRG2 is important for ensuring centrosome duplication and accurate chromosome segregation, and its disruption leads to centrosome amplification and spindle checkpoint defects, contributing chromosome instability.…”

“…5 Cui et al 4 showed that ECRG2 interacted with MT2A physically and induced apoptosis of cancer cells. Further, Huang et al 6 reported that ECRG2 inhibited invasion and metastasis of lung cancer cell by suppressing urokinase-type plasmin activator/plasmin pathway. Depletion of ECRG2 contributes to lung cancer cell invasion by regulating extracellular matrix degradation, 5 representing that ECRG2 is a novel therapeutic target for cancer.…”

NMR structure note: human esophageal cancer-related gene 2

“…Esophageal cancerrelated gene 2 (ECRG2), also named serine peptidase inhibitor Kazal-type 7 (SPINK7), was identified as a growth-regulating gene by comparing normal esophageal epithelia and primary squamous cell carcinomas tissues from high incidence families in Lin-Xian County of China using differentially displayed PCR (Su et al 1998;Cui et al 2010). It has been shown that ECRG2 is a tumor suppressor gene involved in the regulation of cell proliferation, induction of apoptosis, and inhibition of cancer cell migration, invasion and metastasis (Cui et al 2003;Huang et al 2007). ECRG2 also participates in centrosome amplification in a p53-dependent manner and has a role in maintaining chromosome stability (Cheng et al 2008).…”

“…ECRG2 also participates in centrosome amplification in a p53-dependent manner and has a role in maintaining chromosome stability (Cheng et al 2008). Recently, it was found that ECRG2 regulates cell migration/invasion through urokinase-type plasmin activator (uPA)/urokinase-type plasmin activator receptor (uPAR) pathway by directly inhibiting uPA/plasmin activity, and may represent a novel therapeutic target for cancer (Huang et al 2007;Cheng et al 2009Cheng et al , 2010Cui et al 2010).…”