Galectin-1 is up-regulated by RASSF1A gene in human gastric carcinoma cell line SGC7901

Deregulation of annexin-A1 and galectin-1 expression in precancerous gastric lesions: intestinal metaplasia and gastric ulcer

OBJECTIVE

Annexin-A1 (ANXA1/AnxA1) and galectin-1 (LGALS1/Gal-1) are mediators that play an important role in the inflammatory response and are also associated with carcinogenesis. We investigated mRNA and protein expression in precancerous gastric lesions that participate in the progression cascade to gastric cancer, such as intestinal metaplasia (IM) and gastric ulcer (GU).

METHODS

Quantitative real-time PCR (qPCR) and immunohistochemical techniques were used to analyze the relative quantification levels (RQ) of ANXA1 and LGALS1 mRNA and protein expression, respectively.

RESULTS

Increased relative expression levels of ANXA1 were found in 100% of cases, both in IM (mean RQ = 6.22 ± 0.06) and in GU (mean RQ = 6.69 ± 0.10). However, the LGALS1 presented basal expression in both groups (IM: mean RQ = 0.35 ± 0.07; GU: mean RQ = 0.69 ± 0.09). Immunohistochemistry revealed significant positive staining for both the AnxA1 and Gal-1 proteins in the epithelial nucleus and cytoplasm as well as in the stroma of the IM and GU groups (P < 0.05) but absence or low immunorectivity in normal mucosa.

CONCLUSION

Our results bring an important contribution by evidencing that both the AnxA1 and Gal-1 anti-inflammatory proteins are deregulated in precancerous gastric lesions, suggesting their involvement in the early stages of gastric carcinogenesis, possibly due to an inflammatory process in the gastric mucosa.

Expression of RASSF1A and Cyclin A2 in intrahepatic cholangiocarcinoma

AIM: To detect the expression of RASSF1A and CyclinA2 in intrahepatic cholangiocarcinoma (ICC) and to analyze their relationship with the biological behavior of ICC.

METHODS: Thirty ICC specimens and 18 tumor-adjacent tissue specimens were collected from January 2010 to September 2011 in Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. The expression of RASSF1A and CyclinA2 in these specimens was detected by immunohistochemistry. The relationship between the expression of RASSF1A and CyclinA2 and clinicopathologic parameters of ICC was then analyzed.

RESULTS: The positive rate of expression of RASSF1A in ICC was significantly lower than that in tumor-adjacent tissue (36.67% vs 83.33%, P < 0.05), while the positive rate of expression of Cyclin A2 in ICC was significantly higher than that in tumor-adjacent tissue (73.33% vs 11.11%, P < 0.05). There was a negative correlation between the expression of RASSF1A and that of Cyclin A2 in ICC (P < 0.01, r = 0.54).

CONCLUSION: RASSF1A and CyclinA2 may be involved in the occurrence and development of ICC. Inactivation of RASSF1A may contribute to the invasion and metastasis of ICC. CyclinA2 may play a significant role in the tumor inhibition mechanism mediated by RASSF1A.