ABSTRACT
Gastrin is mainly secreted by the G cells in antrum and the upper part of small intestine.Gastrin receptor distributes in various tissues.Gastrin and its receptor have several functions including regulating cell growth and differentiation,inhibiting apoptosis,promoting cell proliferation,invasion and metastasis.Studies have shown that gastrin and its receptor involve with various cancers occurrence and development.Gastrin and its receptor can be used to diagnosis early gastric cancer,and be used as a potential targets in gastric carcinoma treatment.The relationship of gastrin and its receptor with gastric carcinoma were reviewed in this paper.
ABSTRACT
Objective To investigate the regulation role of gastric cancer related miR-148a on gastrin receptor CCKBR expression, and find the correct binding sites of miR-148a in CCKBR 3’UTR.Methods The potential binding sites of miR-148a in the CCKBR 3’UTR were predicted with the bioinformatic tools;The miR-148a expressing plasmid was constructed by PCR, and miR-148a expression was verified by Northern Blot;The luciferase report plasmids containing the wild type and mutated binding sites of CCKBR 3’ UTR were constructed, and were used to study the regulation mechanism and identify the binding sites of miR-148a by luciferase activity analysis; The regulation effect of miR-148a on CCKBR protein expression was checked by Western Blot.Results Three potential binding sites of miR-148a in the CCKBR 3’ UTR were found; The miR-148a expressing plasmid was constructed successfully, and highly expressed miR-148a after transfected to gastric cancer cells;The inhibitory effect of miR-148a on CCKBR protein expression was checked by Western Blot.Over-expression of miR-148a inhibited CCKBR expression by directly binding to the binding site in CCKBR 3’UTR 423bp.Conclusion CCKBR is a target of miR-148a, and its expression is inhibited by the binding of miR-148a on its 3’ UTR, indicating that miR-148a may participates in the progression of gastric cancer by regulating CCKBR expression.
ABSTRACT
AIM To establish radioligand binding assay of gastrin receptor in rat gastric parietal cell. METHODS Using 125 I labeled [Leu 15 ] gastrin 17 I as the radioligand, rat gastric parietal cells as the receptor preparations. RESULTS In the range of the study, a Scatchard plot of the binding was made by Ligand program with an equilibrium K d of approximately 1 249?10 -10 mol?L -1 and a maximum binding capacity of 4 4604?10 -12 mol?L -1 . The amount of gastrin binding was strongly associated with the cell concentration of rat gastric parietal cell preparations ranged from 0 25?10 9 to 2?10 9 cells?L -1 . The variant coefficent of the binding assay was 7 04% within the same sample. The competitive inhibiting analyses showed that 125 I gastrin was bound to gastric parietal cell preparations with a high specificity. CONCLUSION The radioligand binding assay of gastrin receptor in rat gastric parietal cell preparations meets the criteria for establishing receptor binding assay.