The present study explored a new downstream regulator of Stat‐3 signaling, miR‐499‐5p and its target gene programmed cell death 4 (PDCD4) in cell survival and metastasis of gastric cancer. Our results showed that miR‐499‐5p is significantly upregulated in human gastric cancer cell line SGC‐7901. We further demonstrated that miR‐499‐5p promotes gastric cancer cell proliferation and invasion in vitro. Mechanistically, we demonstrated that upregulation of miR‐499‐5p expression associated with inhibition of PDCD4; STAT3 transcriptional activation by IL‐6 is crucial for the upregulation of miR‐499‐5p expression. These results indicate that the STAT3‐miR‐499‐5p‐PDCD4 signaling axis plays an important role in gastric cancer progression and a potentially therapeutic target for gastric cancer treatment.
To investigate the correlation and clinical significance between programmed cell death factor 4 (PDCD4) and epidermal growth factor receptor 2 (Her-2) expressions and clinicopathological parameters in patients with gastric cancer, a total of 65 cases of gastric cancer and the corresponding normal mucosa with PDCD4 and Her-2 protein expressions were detected by SP immunohistochemical staining, and 50 cases of gastric cancer and the corresponding normal mucosa with PDCD4 and Her-2 protein expression quantities were detected by Western blot, in order to analyze the relationship between the positive expressions of PDCD4 and Her-2 protein and the clinicopathological features of patients with gastric cancer. The results showed that the positive rate of PDCD4 protein expression in gastric cancer tissues was 7.7%, which was significantly lower than that in the corresponding normal tissues, that is, 77.5% (P < 0.05); the positive rate of Her-2 expression was 41.5%, which was significantly higher than that of the corresponding normal tissues, which is 2.5% (P < 0.05). The Western blot test showed that the expression of PDCD4 protein in gastric cancer was 0.3105 ± 0.0073, which was significantly lower than that in the corresponding normal tissues, that is, 0.9428 ± 0.0127 (P < 0.05); the expression level of Her-2 protein in gastric cancer tissues was 0.9428 ± 0.0127, which was significantly higher than that of the corresponding normal mucosa, which is 0.2054 ± 0.0264 (P < 0.05). The positive expressions of PDCD4 (5/65) and Her-2 (27/65) were significantly correlated with the differentiation degrees and TNM stages of gastric cancer (P < 0.05). However, no significant correlation can be observed from Table 2 (P > 0.05), regarding sex, age, tumor size, and lymph node metastasis. Our research claimed that PDCD4 and Her-2 may play an important role in the invasion and metastasis of gastric cancer, which has a negative correlation with biological behaviors of gastric cancer. The low expression of PDCD4 and the high expression of Her-2 in gastric cancer may promote the occurrence and progression of cancer. The PDCD4 and Her-2 test can be used as an index to evaluate the malignant biological behaviors of gastric cancer and prognosis, and provide a theoretical basis for targeted therapy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.