Differential expression of cholecystokinin A receptor in gallbladder cancer in the young and elderly suggests two subsets of the same disease?

Heterodimerization of cholecystokinin 1 and cholecystokinin 2 receptors in gallbladder cancer: a new mechanism for carcinogenesis

PURPOSE

Cholecystokinin is present in abundance in gallbladder tissue and mediates function through two structurally related receptors, CCK1R and CCK2R. Heterodimerization of these receptors is known to impact cell growth in vitro. However, the significance of these heterodimers in gallbladder carcinogenesis is relatively unknown.

METHODS

Therefore, we evaluated the expression and the dimerization status of CCK1 and CCK2 receptors in human gallbladder carcinoma cell line (GBC-SD) and resected gallbladder tissue from normal (n = 10), cholelithiasis (n = 25) and gallbladder cancer (n = 25) by immunofluorescence/immunohistochemistry and western blot. The dimerization status of CCK1R and CCK2R was evaluated by co-immunoprecipitation. To understand the effect of heterodimerization of these receptors on growth-related signaling pathways, the expression of p-AKT, rictor, raptor and p-ERK was evaluated by western blot.

RESULTS

We demonstrated the expression and heterodimerization of CCK1 and CCK2 receptor in GBC-SD gall bladder carcinoma cell line. Knockdown of CCK1R and CCK2R in the cell line led to significant reduction in p-AKT (P = 0.005; P = 0.0001) and rictor (P < 0.001; P < 0.001) levels. In tissue samples, significantly higher expression of CCK1R and CCK2R was observed in gallbladder cancer when compared to other groups both by immunohistochemistry (P = 0.008 and P = 0.013) and western blot (P = 0.009 and P = 0.003). An increase in heterodimer formation of CCK1R with CCK2R was observed in gallbladder cancer when compared to normal and cholelithiasis tissues. No significant difference in the expression of p-AKT and p-ERK was observed between the three groups.

CONCLUSION

Our results provide the first evidence of heterodimerization of CCK1R and CCK2R in gallbladder tissue, and its association with development of gallbladder cancer. This finding has potential clinical and therapeutic significance.

Using proton pump inhibitors increases the risk of hepato-biliary-pancreatic cancer. A systematic review and meta-analysis

Background: More and more studies are focusing on the adverse effects and damage caused by PPI abuse, we carried out a systematic review and meta-analysis for assessing whether the proton pump inhibitor (PPI) leads to hepato-biliary-pancreatic cancer.

Methods: PubMed, EMBASE and Web of Science were searched until 1 July 2022, 25 studies (17 case-control and 8 cohort studies; 2741853 individuals) included in this study. Pooled Odd Ratios (ORs) were used for random effect models. Sensitivity analysis and dose-response analysis, subgroup analysis were all conducted.

Results: The aggregate OR of the meta-analysis was 1.69 (95% confidence interval (CI): 1.42–2.01, p = 0.01) and heterogeneity (I² = 98.9%, p < 0.001) was substantial. According to stratified subgroup analyses, the incidence of hepato-biliary-pancreatic cancer was associated, expect for study design, study quality and region. Risk of hepato-biliary-pancreatic cancer is highest when people is treated with normal doses of PPI. The risks decrease and become insignificant when the cumulative defined daily dose (cDDD) increases.

Conclusion: The use of PPI may be associated with an increased risk of hepato-biliary-pancreatic cancer. Hence, caution is needed when using PPIs among patients with a high risk of hepato-biliary-pancreatic cancer.

A Comparative Analysis of Clinical Characteristics and Histomorphologic and Immunohistochemical Spectrum of Gallbladder Carcinoma in Young Adults (< 45 Years) and Elderly Adults (> 60 Years)

Gallbladder carcinoma (GBC) is more frequent after 60 years of age; its behavior in young adults has not been much studied. A retrospective analysis was performed in patients who underwent a cholecystectomy procedure between the years 2001 to 2016. A group of young patients (< 45) were compared with elderly patients (> 60 years) with reference to various clinical, histomorphologic, and immunohistochemical parameters. Statistical analysis was performed using t test and Fisher's test. Survival curves were calculated by Kaplan-Meier actuarial survival curves and log-rank tests. One hundred and one patients with GBC were observed during the study period. Of these, 14 patients (13.9%) belonged to the study group (age range 20 to 45 years) and 43 patients (42.6%) constituted the comparison elderly control group (age range 60 to 80 years). Forty-four pts. were in the middle-aged group (46 to 59 years) and were thus excluded from the study. With reference to age (< 45 and > 60), no significant difference was found in sex (females 64.3% vs 69.8%, p = 0.7), presence of gall stones (64% vs 60%, p = 0.8), advanced disease at presentation (T4) (14.3% vs 7%, p = 0.40), incidental detection of gallbladder carcinoma (28.5% vs 28%, p = 0.9), tumor stage at presentation (stage I/II) (35.7% vs 49%, p = 0.39), and poor differentiation (tumor grades G3) (14% vs 12%, p = 0.79). Full-length involvement (28.5% vs 11.6%, p = 0.015) of the gallbladder and abundant tumor necrosis (43% vs 14%, p = 0.021) were more common in the younger patients group whereas adenosquamous and pure squamous cell carcinoma were predominantly observed in elderly patients. Immunohistochemical studies showed higher percentage of overexpression of p53 and Ki-67 proliferation indices in the younger population. Overall survival in younger patients was 48 months whereas in elderly patients it was 36 months. Histological markers denoting aggressive tumor behavior were observed in gallbladder carcinomas of younger individuals; further studies are needed to delineate the differences in molecular mechanisms involved in progression of the tumor in the two groups.

CCK1 receptor is involved in the regulation of protein lysine acetylation in GBC-SD cells and gallbladder carcinoma

BACKGROUND

CCK1 (cholecystokinin receptor 1) and protein lysine acetylation were associated with several cancers, respectively. However, whether they are involved in the alternation of gallbladder carcinoma is unknown.

AIMS

This study investigated the characteristics of CCK1 and protein lysine acetylation in GBC-SD cells and carcinoma of gallbladder.

METHODS

The expression and localization of CCK1 were detected by western blot analysis and indirect immunofluorescence. GBC-SD cells were treated with CCK-8 and CCK-8+CCK1 inhibitor. The protein lysine acetylation from cells, as well as tissues of gallbladder carcinoma, was examined by western blotting.

RESULTS

CCK1 receptor was expressed and localized in the GBC-SD cells. The synthetic octapeptide of CCK (CCK-8) could accelerate the lysine acetylation of a subset of proteins in dose-dependent manners in GBC-SD cells. Further investigation demonstrated that the specific inhibitor (CR1409) of CCK1 receptor could attenuate the CCK8-induced increase of protein lysine acetylation. In addition, we revealed that the rise of CCK1 receptor expression is associated with the increase of protein lysine acetylation in tissues from carcinoma of gallbladder.

CONCLUSIONS

CCK might regulate protein lysine acetylation via CCK1 receptor.

Clinicopathologic characteristics of young patients with gallbladder cancer

Gallbladder cancer is the most common biliary tract cancer and the fifth most common cancer of the digestive system. However, the clinicopathologic features of gallbladder cancer in young Korean patients have not been studied. This study included 101 consecutive cases of gallbladder cancer that underwent cholecystectomy at Kangbuk Samsung Hospital from December 1990 to March 2011. The patients were divided into two groups by age at initial diagnosis of gallbladder cancer: a young patient group aged less than 45 years and an old patient group aged 45 or older. The young patient group included 10 patients with mean age of 38 (range, 29-44 years). Compared with the old patient group, the young patient group showed polypoid tumor appearance (p=0.014), lower pT stage (p=0.023), more frequent adenoma background (p=0.009), and less frequent dysplasia in remaining mucosa (p=0.001). The disease-related survival rate after 13.5 months was significantly more favorable for the young patients. Gallbladder cancers in young Korean patients have distinct clinicopathologic features of a high frequency of cancer arising in adenoma, rare association with intestinal metaplasia and dysplasia, and a favorable patient's prognosis. These findings suggest that the adenoma-carcinoma pathway could contribute more to gallbladder cancer carcinogenesis in young Korean patients than the metaplasia-dysplasia-carcinoma pathway.

Polymorphism and Expression Profile of Cholecystokinin Type A Receptor in Relation to Gallstone Disease Susceptibility

In the present study, we investigated expression pattern of Cholecystokinin type A receptor (CCKAR) in relation to its commonly studied polymorphism (rs1800857, T/C) in gallstone disease (GSD) patients and controls. A total of 502 subjects (272 GSD and 230 controls) were enrolled, and genotyping was performed by evaluating restriction fragments of PstI digested DNA. For analyzing expression pattern of CCKAR in relation to polymorphism, gallbladder tissue samples from 80 subjects (GSD-55; control-25) were studied. Expression of CCKAR mRNA was evaluated by reverse transcriptase-PCR and confirmed using real-time PCR. Protein expression was evaluated by enzyme-linked immunosorbent assay. We observed significantly (p < 0.0001) lower expression of CCKAR mRNA and protein in GSD tissues as compared with control. Significantly higher frequency of A1/A1 genotype (C/T transition) (p = 0.0005) was observed for GSD as compared with control. Expression of CCKAR protein was found to be significantly lower (p < 0.0001) in A1/A1 genotype as compared with other genotypes for GSD patients. Perhaps, this is the first report providing evidence of alteration in CCKAR expression in relation to its polymorphism elucidating the molecular pathway of the disease. Additional investigations with lager sample size are needed to confirm these findings.

Expression of CCK Receptors in Carcinoma Gallbladder and Cholelithiasis: A Pilot Study

BACKGROUND

Gastrin and cholecystokinin (CCK) receptors are trophic for various gastrointestinal malignancies. Their role in gallbladder cancer has not been widely studied.

OBJECTIVES

To identify expression of CCK-A and CCK-B receptors in the tissue and blood of patients suffering from carcinoma (CA) gallbladder and gallstone disease and to compare expression of CCK A and B receptors in the gall bladder tissue and blood of healthy individuals and patients of CA gallbladder, and gallstone diseases.

MATERIALS AND METHODS

Forty nine subjects of both genders were recruited, comprising of 22 patients of CA gall bladder, 19 cases of cholelithiasis and, 8 normal gallbladders obtained from patients operated for trauma of the biliary system or Whipple's procedure. RNA extraction and cDNA formation for CCK-A and CCK-B receptors were carried out. Real Time PCR was performed on cDNA and threshold cycle (Ct) value of each sample was obtained and ΔCt was calculated. Chi-square test for comparing two groups and ANOVA test for comparing multiple groups were applied and if p<0.05 then Dunnett-C test was performed.

OBSERVATION AND RESULTS

Both CCK-A and CCK-B receptors were expressed irrespective of its origin in all tissues and blood samples studied; be it normal, Cholelithiasis or CA gallbladder and there was no difference among them (p>0.05).

CONCLUSION

This preliminary study showed higher expression of CCK-A receptors in patients of cholelithiasis and decreased expression of CCK-A receptors in patients of CA gallbladder as compared to normal gallbladder although it did not rise to statistical significance.