Positive Expression Rate Of PTEN Research Articles

The expression of SOX9, Tiam1, and PTEN is correlated with angiogenesis and prognosis in gastric cancer.

BackgroundWith a high rate of metastasis and recurrence, gastric cancer (GC), a common malignant tumor, often has a poor prognosis. GC tissues have abnormal expressions of the Sry-related HMG-box family of transcription factors (SOX9), T-lymphoma invasion and metastasis-inducing factor 1 (Tiam1), and phosphatase and tensin homolog deleted on chromosome ten (PTEN). Meanwhile, vascular endothelial growth factor (VEGF) have been reported to play an important role in tumor angiogenesis. This study aimed to analyze the correlation of SOX9, Tiam1, and PTEN with angiogenesis and prognosis in GC.MethodsA total of 90 patients who underwent GC surgery at our hospital between January 2017 and October 2018 were enrolled. The expressions of SOX9, Tiam1, PTEN, and VEGF in GC tissues and adjacent normal tissues were detected by immunohistochemistry and the differences were analyzed. Spearman’s correlation coefficient was applied to analyze the relationship between the expression levels of SOX9, Tiam1, PTEN, and VEGF. The patients were followed-up.ResultsThe positive expression rates of SOX9, Tiam1, PTEN, and VEGF in GC tissues were 75.56%, 61.11%, 52.22%, and 48.89%, respectively, compared with 6.67%, 4.44%, 97.78%, and 2.22%, respectively, in the adjacent normal tissues (P<0.05). Spearman’s correlation analysis showed that the expression of SOX9 (r=0.349, P=0.001) and Tiam1 (Tiam1: r=0.370, P=0.000) in GC tissues was positively correlated with VEGF expression; however, PTEN was negatively correlated with VEGF (r=−0.311, P=0.000). There were no significant differences in SOX9, Tiam1, or PTEN expression in GC tissues from patients of different genders or ages (P>0.05). When the tumor was low differentiated, with lymph node metastasis or high TNM staging, the positive expression rates of SOX9 and Tiam1 were significantly increased (P<0.05), while the positive expression rate of PTEN was significantly decreased (P<0.05). The log-rank test results showed that the three-year survival rates of the groups with positive SOX9 (54.41%) and Tiam1 expression (49.09%) were significantly lower than those of the groups with negative SOX9 and Tiam1 expression (77.27% and 77.13%, respectively; P<0.05). The 3-year survival rate in the PTEN positive expression group was significantly higher than that of the PTEN negative expression group (76.60% vs. 41.80%; P<0.05).ConclusionsSOX9 and Tiam1 are highly expressed, in GC tissues while there is a low expression of PTEN. The expression levels of SOX9, Tiam1, and PTEN are all linearly correlated with VEGF expression, and they have important effects on angiogenesis and is closely related to the three-year survival rate of patients with GC.

MiR-214 targets the PTEN-mediated PI3K/Akt signaling pathway and regulates cell proliferation and apoptosis in ovarian cancer.

The present study aimed to investigate the potential role of microRNA (miR)-214 in targeting the phosphatase and tensin homolog (PTEN)-mediated phosphoinositide 3-kinase (PI3K)/Akt signaling pathway in ovarian cancer (OC). The target gene of miR-214 was determined by luciferase reporter gene assay and was indicated to be PTEN. Human SK-OV-3 cells were transfected with a miR-214 inhibitor and a miR-214 mimic, and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect relative expression of miR-214. The MTT assay was performed to detect cell viability following transfection. Cell cycle and apoptosis were assessed by staining with propidium iodide (PI) and double staining with Annexin V/PI, respectively. The expression levels of PTEN and PI3K/Akt signaling pathway-associated proteins were detected by western blot analysis. The expression of miR-214 in tumor tissues and normal tissues was detected by RT-qPCR, and PTEN expression was detected by immunohistochemistry. SK-OV-3 cells transfected with a miR-214 inhibitor showed significantly inhibited cell viability and proliferation, and markedly increased apoptotic rate. SK-OV-3 cells transfected with miR-214 mimic showed significantly increased viability and proliferation, and markedly decreased apoptotic rate. The cells transfected with a miR-214 inhibitor exhibited significantly upregulated PTEN expression and significantly downregulated phosphatidylinositol (3,4,5)-trisphosphate (PIP3), phosphorylated (p)-Akt and p-glycogen synthase kinase (GSK)-3β expression. The cells transfected with miR-214 mimic exhibited significantly downregulated PTEN expression and significantly upregulated PIP3, p-Akt and p-GSK-3β expressions. The OC tissues exhibited an increased expression of miR-214 and a reduced positive rate of PTEN expression compared with adjacent normal tissues. miR-214 may activate the PI3K/Akt signaling pathway by downregulating the targeted PTEN, which may promote OC cell proliferation and inhibit apoptosis.

Expression of PTEN and KAI1 tumor suppressor genes in pancreatic carcinoma and its association with different pathological factors

Pancreatic carcinoma is a common cancer type with a poor prognosis. The aim of the present study was to examine the expression of tumor suppressor genes phosphatase and tensin homolog deleted in chromosome 10 (PTEN) and KAI1 in pancreatic carcinoma and its association with clinical pathological factors. A total of 50 hospitalized cases of pancreatic cancer including 28 males and 22 females aged 31–82 years were included in the present study. Ten cases of normal pancreatic tissue were obtained from cadavers and served as the controls. The pancreatic specimens were embedded in paraffin blocks and slides were prepared for immunohistochemical analysis to determine the expression of PTEN and KAI1 in normal pancreatic tissue and pancreatic carcinoma samples. The positive expression rate of PTEN in the normal pancreatic tissue was higher than that in pancreatic carcinoma (P<0.05), while the positive expression rate of KAI1 in the normal pancreatic tissue was lower than that in pancreatic carcinoma (P<0.05). Pathological factors such as clinical stage of disease, histological grade and the presence or absence of lymphatic metastasis significantly affected the expression of PTEN and KAI1 (P<0.05). In conclusion, the positive expression of PTEN and KAI1 in pancreatic carcinoma is closely associated with the development of pancreatic carcinoma.

Chemoresistance is associated with Beclin-1 and PTEN expression in epithelial ovarian cancers.

The aim of the present study was to investigate the protein expression of the autophagy-related genes, BECN1 and PTEN, and the association with drug resistance in epithelial ovarian cancers. In total, 40 patients with pathologically diagnosed epithelial ovarian cancer were divided into a chemotherapy-sensitive group (n=20) and a chemotherapy-resistant group (n=20), according to the results of the pre- or post-operative normative chemotherapy and the post-operative follow-up. The protein expression of the phosphatase and tensin homolog (PTEN) and the BECN1 gene product, Beclin-1, was analyzed using immunohistochemistry in the 40 patients with ovarian carcinoma. The positive rate of Beclin-1 expression was significantly lower in the resistant group (35.0%) compared with the sensitive group (50.0%). The positive rate of PTEN expression was also significantly lower in the resistant group (30.0%) compared with the sensitive group (65.0%). Furthermore, the differences in the expression rates were revealed to be significant (P<0.05). The expression of Beclin-1 was identified to be positively correlated with the expression of PTEN (rs=0.816; P<0.0001). The low expression of the Beclin-1 and PTEN proteins in the ovarian cancer tissues was revealed to be closely associated with drug resistance. Therefore, Beclin-1 may interact with PTEN to participate in the mechanism of drug resistance and the changes in macrophage activity observed in cases of drug-resistant ovarian cancer.

Promoter region methylation and loss of protein expression of PTEN and significance in cervical cancer.

The genetic basis underlying cervical tumorigenesis and progression are largely unknown. Phosphatase and tensin homologue (PTEN) is a tumor suppressor gene, and genetic changes of PTEN occurs in various types of cancer suggesting that the inactivation of PTEN may play an important role in the pathogenesis of a variety of human malignancies. In the present study, 102 cervical cancer specimens were examined for the expression of the PTEN gene and promoter methylation using methylation-specific-polymerase chain reaction and immunohistochemistry. The PTEN gene mutation was also assessed using PCR single-strand conformational polymorphism. We examined the correlation between PTEN expression and its associated methylation status and the clinical characteristics of cervical cancer. The results showed that there was one case of an A to G point mutation on exon 9 of the PTEN gene in the cervical cancer tissues. This mutation caused the change of aspartic acid to glycine, and the rate of mutation was 1%. The PTEN gene methylation rate of cervical cancer was 62% (63/102) and the rate was associated with the International Federation of Gynecology and Obstetrics stage, cell differentiation, tumor size and lymph node metastasis (P<0.05). The positive rate of PTEN expression was 49% (50/102) in cervical carcinoma and the PTEN expression between stage I-II and III-IV [60 (27/45) vs. 40% (23/57)] was statistically significant (P<0.01). The PTEN gene expression between the metastasis and no lymph node metastasis groups [26 (10/38) vs. 63% (40/64)] was significantly different (P<0.01). The PTEN gene promoter methylation and its protein expression had a significant correlation (P=0.042). These results suggest that hypermethylation can inactivate the transcription of PTEN and reduce its protein expression. Downregulated PTEN expression is involved in the pathogenesis, invasion and metastasis of cervical cancer, possibly by regulating the balance between apoptosis and proliferation. Therefore, the PTEN expression may be a good marker for the prognosis of cervical cancer.

Expression and significance of PTEN and HIF-1α proteins in sinonasal inverted papilloma

To investigate the expression and clinical significance of phosphatase and tensin homology deleted on chromosome ten (PTEN) and hypoxia-inducible factor 1 alpha (HIF-1α) in sinonasal inverted papilloma (SNIP) of different pathological grades. Fifty-five paraffin samples from patients with SNIP and a control group of 10 paraffin samples of patients with normal nasal cavity mucosa (NM) who underwent inferior turbinectomy were consisted in this study. Among the 55 cases of SNIP, 30 cases were without dysplasia subtypes, 11 cases were with dysplasia subtypes, and 14 cases with canceration to squamous cell carcinoma (SCC) subtypes. PTEN and HIF-1α expression in SNIP was detected by immunohistochemistry. The differences between NM and SNIP, and among the three subtypes were analyzed, and the relationship between PTEN, HIF-1α expression and SNIP recurrence and the correlation between PTEN expression and HIF-1α expression were also analyzed. SPSS 16.0 software was used to analyze the data. The positive expression rate of PTEN in NM and SNIP was 100% and 65.5%, the difference was significant (U = 147, P = 0.014), while HIF-1α was 0 and 30.9%, the difference was significant (U = 190, P = 0.045). The positive expression rate of PTEN in SNIP without dysplasia, SNIP with dysplasia and NSCC was 83.3%, 63.6%, 28.6%, respectively, the difference was significant (H = 12.644, P = 0.002); while HIF-1α was 16.7%, 45.5%, 50.0%, respectively, the difference was significant (H = 8.292, P = 0.016). A total of 22 SNIP patients recurred. PTEN had lower expression in recurrent SNIP (45.5%) than that in non-recurrent SNIP (82.8%), and the difference was significant(χ² = 7.834, P = 0.005). However, the expression of HIF-1α had no significant difference between recurrent SNIP and the SNIP which had no recurrence (χ² = 0.901, P = 0.343). The expression of PTEN protein was negatively correlated with that of HIF-1α protein (r = -0.503, P = 0.001). PTEN expression decreased graduately with the severity of malignancy of SNIP, but HIF-1α increased. The expression of HIF-1α was induced by hypoxia, which may negatively effect the expression of PTEN, and both HIF-1α and PTEN may play critical roles in the progress of SNIP. PTEN is one of the factors responsible for the postoperative recurrence of SNIP.

Expression of Survivin and PTEN in gastric cancer and its clinic significance

Objective To investigate the relationship among Survivin, PTEN and the occurrence, development, soakage and prog-nesis of gastric cancer. Methods The in-situ hybrization technique, immunochemistry and TUNEL method were used to detect the expres-sion of survivin mRNA, PTEN protein and apoptotic cell. Results The positive rate of survivin expression in gastric cancer was obvious higher than that in para-cancer tissue(P <0.01). Moreover, survivin expression rate in advanced clinical stage and low differentiation gastric cancer degree.was higher, compared with para-cancer tissue (P <0.01, P <0.05). The positive rate of PTEN expression in gas-tric cancer was obvious lower than that in pars-cancer tissue (P <0.01). The positive rate of PTEN expression in advanced clinical stage and low differentiation degree of tissue in gastric cancer was lower (P < 0.01). Furthermore, survivin and apoptesis indexes manifested negative relationship in gastric cancer(r =-0.861, P < 0.01), While PTEN and apoptosis indexes manifested positive relationship (r = 0.832, P < 0.01). Conclusions Survivin could be used as a novel marker to detect gastric cancer. PTEN gene lost function, which maybe promote the origin, growth, soakage and metastasis of gastric cancer. Key words: Microtuhle-associated proteins/BI; Tumor suppressor proteios/BI ; Stomach neoplasms/ME