Expression of PTTG1 and PTEN in endometrial carcinoma: correlation with tumorigenesis and progression

GLI1 and PTTG1 expression in colorectal carcinoma patients undergoing radical surgery and their correlation with lymph node metastasis

BACKGROUND

Few studies have investigated the expression of GLI1 and PTTG1 in patients undergoing radical surgery for colorectal carcinoma (CRC) and their association with lymph node metastasis (LNM). Therefore, more relevant studies and analyses need to be conducted.

AIM

To explore GLI1 and PTTG1 expression in patients undergoing radical surgery for CRC and their correlation with LNM.

METHODS

This study selected 103 patients with CRC admitted to our hospital between April 2020 and April 2023. Sample specimens of CRC and adjacent tissues were collected to determine the positive rates and expression levels of GLI1 and PTTG1. The correlation of the two genes with patients' clinicopathological data (e.g., LNM) was explored, and differences in GLI1 and PTTG1 expression between patients with LNM and those without were analyzed. Receiver operating characteristic (ROC) curves were plotted to evaluate the predictive potential of the two genes for LNM in patients with CRC.

RESULTS

Significantly higher positive rates and expression levels of GLI1 and PTTG1 were observed in CRC tissue samples compared with adjacent tissues. GLI1 and PTTG1 were strongly linked to LNM in patients undergoing radical surgery for CRC, with higher GLI1 and PTTG1 levels found in patients with LNM than in those without. The areas under the ROC curve of GLI1 and PTTG1 in assessing LNM in patients with CRC were 0.824 and 0.811, respectively.

CONCLUSION

GLI1 and PTTG1 expression was upregulated in patients undergoing radical surgery for CRC and are significantly related to LNM in these patients. Moreover, high GLI1 and PTTG1 expression can indicate LNM in patients with CRC undergoing radical surgery. The expression of both genes has certain diagnostic and therapeutic significance.

UBE2C serves as a prognosis biomarker of uterine corpus endometrial carcinoma via promoting tumor migration and invasion

The biological functions of ubiquitin-conjugating enzymes E2 (UBE2) family members in uterine corpus endometrial carcinoma (UCEC) remains unclear. Our study aimed to systematically analyze the expression patterns, prognostic value, biological functions and molecular regulatory mechanisms of UBE2 family in UCEC. Among nine screened UBE2 family members associated with UCEC, UBE2C was the most significantly overexpressed gene with poor prognosis. High expression levels of UBE2C in UCEC was correlated with stages, histological subtypes, patient's menopause status and TP53 mutation. Three molecules (CDC20, PTTG1 and AURKA), were identified as the key co-expression proteins of UBE2C. The generic alterations (mutation, amplification) and DNA hypomethylation might contribute to UBE2C's high expression in UCEC. Furthermore, in vitro experiments showed that the interference of UBE2C inhibited the migration and invasion of endometrial cancer cells, while partially impact cell proliferation and didn't impact the expression of epithelial-mesenchymal transition (EMT) markers. Using comprehensive bioinformatics analysis and in vitro experiments, our study provided a novel insight into the oncogenic role of UBE2 family, specifically UBE2C in UCEC. UBE2C might serve as an effective biomarker to predict poor prognosis and a potential therapeutic target in clinical practice.

Clinical significance of securin expression in solid cancers: A PRISMA-compliant meta-analysis of published studies and bioinformatics analysis based on TCGA dataset

BACKGROUND

Numerous studies have investigated the clinical significance of securin expression in solid cancers; however, the results have been inconsistent. Hence, we performed a meta-analysis of published studies to assess the clinical value of securin expression in patients with solid cancers.

METHODS

The Chinese National Knowledge Infrastructure, Web of Science, PubMed, and EMDASE databases were searched for eligible studies (from inception up to April 2021). Bioinformatics analysis based on The Cancer Genome Atlas dataset was also performed to evaluate the prognostic value of securin expression.

RESULTS

A total of 25 articles with 26 studies were included in the meta-analysis. The results of the meta-analysis implied that high securin expression was positively correlated with unfavorable overall survival (OS) (hazard ratio = 1.52, 95% CI, 1.33-1.73; P < .001) and lymph node metastasis (odd ratio = 2.96, 95% CI, 2.26-3.86; P < .001). Consistently, our bioinformatics analysis showed that increased securin expression was associated with worse OS and shorter disease-free survival in cancer patients.

CONCLUSION

Our study indicated that securin overexpression was positively associated with metastasis and inversely related to the prognosis of patients with solid cancers. However, additional high-quality studies should be conducted to validate these findings.

Identification of hub genes associated with prognosis, diagnosis, immune infiltration and therapeutic drug in liver cancer by integrated analysis

BACKGROUND

Liver cancer is one of the most common cancers and causes of cancer death worldwide. The objective was to elucidate novel hub genes which were benefit for diagnosis, prognosis, and targeted therapy in liver cancer via integrated analysis.

METHODS

GSE84402, GSE101685, and GSE112791 were filtered from the Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were identified by using the GEO2R. The GO and KEGG pathway of DEGs were analyzed in the DAVID. PPI and TF network of the DEGs were constructed by using the STRING, TRANSFAC, and Harmonizome. The relationship between hub genes and prognoses in liver cancer was analyzed in UALCAN based on The Cancer Genome Atlas (TCGA). The diagnostic value of hub genes was evaluated by ROC. The relationship between hub genes and tumor-infiltrate lymphocytes was analyzed in TIMER. The protein levels of hub genes were verified in HPA. The interaction between the hub genes and the drug were identified in DGIdb.

RESULTS

In total, 108 upregulated and 60 downregulated DEGs were enriched in 148 GO terms and 20 KEGG pathways. The mRNA levels and protein levels of CDK1, HMMR, PTTG1, and TTK were higher in liver cancer tissues compared to normal tissues, which showed excellent diagnostic and prognostic value. CDK1, HMMR, PTTG1, and TTK were positively correlated with tumor-infiltrate lymphocytes, which might involve tumor immune response. The CDK1, HMMR, and TTK had close interaction with anticancer agents.

CONCLUSIONS

The CDK1, HMMR, PTTG1, and TTK were hub genes in liver cancer; hence, they might be potential biomarkers for diagnosis, prognosis, and targeted therapy of liver cancer.

Regulation of Glycolysis by Non-coding RNAs in Cancer: Switching on the Warburg Effect

The “Warburg effect” describes the reprogramming of glucose metabolism away from oxidative phosphorylation toward aerobic glycolysis, and it is one of the hallmarks of cancer cells. Several factors can be involved in this process, but in this review, the roles of non-coding RNAs (ncRNAs) are highlighted in several types of human cancer. ncRNAs, including microRNAs, long non-coding RNAs, and circular RNAs, can all affect metabolic enzymes and transcription factors to promote glycolysis and modulate glucose metabolism to enhance the progression of tumors. In particular, the 5′-AMP-activated protein kinase (AMPK) and the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathways are associated with alterations in ncRNAs. A better understanding of the roles of ncRNAs in the Warburg effect could ultimately lead to new therapeutic approaches for suppressing cancer.

Upregulation of PTTG1 is associated with poor prognosis in prostate cancer

Pituitary tumor-transforming gene 1 (PTTG1) is a regulator of chromosome stability. PTTG1 overexpression had been associated with tumor aggressiveness in several cancer types. To examine its prognostic utility in prostate cancer, a tissue microarray including 12 427 tumors with clinical and molecular data was analyzed by immunohistochemistry. PTTG1 immunostaining was largely absent in normal prostate epithelial cells. In cancers, staining was considered weak in 5.4%, moderate in 5.6% and strong in 0.8%. Strong staining was linked to advanced pT stage, high classical and quantitative Gleason grade, high Ki67-labeling index (all P < 0.0001) and lymph node metastasis (P = 0.0083). The prognostic impact of PTTG1 expression was independent of established preoperative and postoperative prognostic features. Comparison with molecular features revealed that PTTG1 upregulation was associated with nine of 12 common genomic deletions (P < 0.05), p53 alterations and high androgen receptor levels (P < 0.001 each), but was unrelated to the TMPRSS2:ERG fusion status. In conclusion, these data identify PTTG1 as a strong and independent prognostic feature in prostate cancer. PTTG1 measurement, either alone or in combination with other biomarkers might be instrumental for determining prostate cancer aggressiveness.

Relationship between polycomb-group protein BMI-1 and phosphatases regulating AKT phosphorylation level in endometrial cancer

The PI3K/AKT pathway is frequently activated in endometrial carcinoma. BMI‐1 (B‐lymphoma Mo‐MLV insertion region 1) protein affects expression of PTEN (phosphatase and tensin homolog) in some cancers, but its significance for endometrial tumorigenesis is not known. The objective of this study was to determine the relationship between BMI‐1 and expression of factors affecting AKT (protein kinase B) phosphorylation level in endometrial cancer. The expression of proteins and mRNAs was investigated in endometrial cancer specimens and samples of non‐neoplastic endometrial tissue by Western blot and RT‐PCR, respectively. The impact of BMI‐1 down‐regulation on AKT phosphorylation and expression of genes coding for several phosphatases were studied in HEC1A cells. The results showed that BMI‐1 depletion caused increase in PHLPP1 and PHLPP2 (PH domain and leucine‐rich repeat protein phosphatases 1/2) expression and decrease in phospho‐AKT (pAKT) level. In more advanced tumours with higher metastatic potential, the expression of BMI‐1 was lower compared to tumours less advanced and without lymph node metastasis. There were significant inverse correlations between BMI‐1 and PHLPPs, especially PHLPP1 in normal endometrial samples. The inverse correlation between BMI‐1 and PHLPP1/PHLPP2 expression was observed in PTEN positive but not PTEN negative cancers. Low PHLPP2 expression in tumours predicted poorer overall survival. BMI‐1 impacts on AKT phosphorylation level in endometrial cells by regulation of PHLPP expression.

Identification of key candidate genes and pathways in endometrial cancer: Evidence from bioinformatics analysis

Endometrial cancer (EC) is the fourth most common cancer in women worldwide. Although researchers are exploring the biological processes of tumorigenesis and development of EC, the gene interactions and biological pathways of EC are not accurately verified. In the present study, bioinformatics methods were used to screen for key candidate genes and pathways that were associated with EC and to reveal the possible mechanisms at molecular level. Microarray datasets (GSE63678, GSE17025 and GSE3013) from the Gene Expression Omnibus database were downloaded and 118 differentially expressed genes (DEGs) were selected using a Venn diagram. Functional enrichment analyses were performed on the DEGs. A protein-protein interaction network was constructed, including the module analysis. A total of 11 hub genes were identified from the DEGs, and functional enrichment analyses were performed to clarify their possible biological processes. A total of 118 DEGs were selected from three mRNA datasets. Functional enrichment demonstrated 27 downregulated genes that were primarily involved in the positive regulation of transcription from RNA polymerase II promoter, protein binding and the nucleus. A total of 91 upregulated DEGs were mainly associated with cell division, protein binding and the nucleus. Pathway analysis indicated that the downregulated DEGs were mainly enriched in pathways associated with cancer, and the upregulated DEGs were mainly enriched in the cell cycle. The 11 hub genes were primarily enriched in the cell cycle, oocyte meiosis, progesterone-mediated oocyte maturation, the p53 signaling pathway and viral carcinogenesis. The integrated analysis showed that cyclin B1, ubiquitin conjugating enzyme E2 C and cell division cycle 20 may participate in the tumorigenesis, development and invasion of EC. In conclusion, the hub genes and pathways identified in the present study contributed to the understanding of carcinogenesis and progression of EC at the mechanistic and molecular-biological level. As candidate targets for the diagnosis and treatment of EC, these genes deserve further investigation.

The Relationship between the Methylation of Promoter Regions of Tumor Suppressor Genes PTEN and APC with Endometrial Cancer

Background:

Endometrial neoplasms is one of the most typical gynecologic diseases with harmful effects. Promoter hypermethylation is an important mechanism of the inactivation of tumor suppressor genes in endometrial neoplasms. Epigenetic changes of the PTEN and APC genes have shown to be present in various cancers. Therefore, in this study, we have investigated the association between the promoter hypermethylation of PTEN and APC genes with endometrial neoplasms.

Methods:

For this study, 28 patients with endometrial neoplasms as well as 22 controls were studied. Analysis of the promoter methylation regions of PTEN and APC genes were performed by Methylation-Specific PCR.

Results:

The frequency of PTEN and APC genes promoter methylation was 28.57% and 17.86% in tumor tissues, and 11.54% and 3.85% in blood samples, respectively. We found a significant relationship between blood and tissue in PTEN methylation (p = 0.0353). Additionally, we determined a closely significant difference between normal tissue and tumor tissue of the PTEN gene (p = 0.0787) and blood and tissue samples of the APC gene in methylated promoter regions (p=0.0623). Furthermore, these results suggest that there is no significant relationship between the promoter methylation of PTEN and APC with clinical characteristics.

Conclusion:

DNA methylation deficiency is a well known highlighted factor in tumorigenesis, therefore the promoter hypermethylation of PTEN and APC can be indicated as a risk factor in endometrial neoplasms.

LINC00184 silencing inhibits glycolysis and restores mitochondrial oxidative phosphorylation in esophageal cancer through demethylation of PTEN

BACKGROUND

Total lesion glycolysis has been reported to be a satisfactory predictor of survival in patients with locally advanced esophageal cancer (EC). The aim of the present study is to investigate the function of long intergenic non-protein coding RNA 184 (LINC00184) on the EC cell glycolysis and mitochondrial oxidative phosphorylation (OXPHOS).

METHODS

The expression of LINC00184 was determined to be highly expressed and PTEN was poorly expressed in EC tissues and cells by RT-qPCR. In order to evaluate the effects of LINC00184 on cellular process in vitro and in vivo, gain- and loss-of-function approaches were performed to alter the expression of LINC00184 and PTEN in EC cells.

RESULTS

Silencing of LINC00184 was observed to inhibit the proliferation, migration, invasion, colony formation, and glycolysis of EC cells and tumour growth, while the mitochondrial OXPHOS was restored. By recruiting DNMT1, LINC00184 enhanced the promoter methylation of PTEN. Inhibition of PTEN promoter methylation suppressed EC glycolysis, whereas, improved mitochondrial OXPHOS. Mechanically, LINC00184 modulated glycolysis and mitochondrial OXPHOS in EC cells through induction of the Akt phosphorylation. After blockage of Akt signaling pathway by an Akt inhibitor, LY294002, the regulatory effects of LINC00184 on the glycolysis and mitochondrial OXPHOS of EC cells were reversed.

CONCLUSION

Taken together, the LINC00184/PTEN/Akt axis mediates glycolysis and mitochondrial OXPHOS in EC cells. This study highlighted a potential intervention target for treating EC.

PTEN expression in endometrial hyperplasia and risk of cancer: a systematic review and meta-analysis

PURPOSE

Rates of progression of endometrial hyperplasia (EH) to endometrial cancer (EC) are highly variable. Among several prognostic markers, PTEN has been recommended by ESMO-ESGO-ESTRO to identify premalignant EH. However, its prognostic accuracy is unclear. Thus, we aimed to assess: (1) the association between PTEN loss in EH and risk of cancer, and (2) the prognostic accuracy of PTEN immunohistochemistry in EH.

METHODS

Electronic databases were searched from their inception to June 2018. All studies assessing PTEN immunohistochemistry in EH and the presence of EC on subsequent hysterectomy were included. Odds ratio (OR), sensitivity, specificity, positive and negative predictive value (PPV and NPV), positive and negative likelihood ratio (LR + and LR-) and area under the curve (AUC) on SROC curves were calculated with subgroup analysis (short/long-term; atypical/non-atypical EH).

RESULTS

Nine retrospective studies assessing 933 EH were included. PTEN loss in EH was significantly associated with increased risk of EC (OR = 3.32, p = 0.001). The association was significant only on the short term ( < 1 year) (OR = 3.45, p = 0.002) and in atypical EH (OR = 1.89, p = 0.01). For overall analysis and short-term/atypical EH subgroup the prognostic accuracy was low, with sensitivity = 0.58 and 0.68, specificity = 0.60 and 0.48, VPp = 0.41 and 0.54, VPN = 0.75 and 0.63, LR +  = 1.80 and 1.37, LR - =  0.62 and 0.56, AUC = 0.687 and 0.721, respectively.

CONCLUSION

PTEN loss in EH is a risk factor for EC, but is not reliable in predicting the risk of EC. In atypical EH, PTEN loss is associated with a risk of concurrent EC of over 50%. This information might integrate the patients' informed consent for the choice of treatment (conservative/hysterectomy), especially in borderline cases. In conservative approach, PTEN loss might suggest closer follow-up.

Loss of PTEN expression as diagnostic marker of endometrial precancer: A systematic review and meta-analysis

INTRODUCTION

Endometrial hyperplasia may be either a benign proliferation or a premalignant lesion. In order to differentiate these two conditions, two possible histologic classifications can be used: the World Health Organization (WHO) classification and the endometrial intraepithelial neoplasia (EIN) classification. The 2017 European Society of Gynaecological Oncology guidelines recommend the use of immunohistochemistry for tumor suppressor protein phosphatase and tensin homolog (PTEN) to improve the differential diagnosis. Nonetheless, its diagnostic accuracy has never been defined. We aimed to assess the diagnostic accuracy of immunohistochemistry for PTEN in the differential diagnosis between benign and premalignant endometrial hyperplasia.

MATERIAL AND METHODS

Electronic databases were searched from their inception to May 2018 for studies assessing immunohistochemical expression of PTEN in endometrial hyperplasia specimens. PTEN status ("loss" or "presence") was the index test; histological diagnosis ("precancer" or "benign") was the reference standard. Sensitivity, specificity, positive and negative likelihood ratios (LR+, LR-), diagnostic odds ratio (DOR), and area under the curve (AUC) on summary receiver operating characteristic curves were calculated (95% CI), with a subgroup analysis based on the histologic classification adopted (WHO vs EIN).

RESULTS

Twenty-seven observational studies with 1736 cases of endometrial hyperplasia were included. Pooled estimates showed low diagnostic accuracy: sensitivity 54% (95% CI 50%-59%), specificity 66% (63%-69%), LR+ 1.55 (1.29-1.87), LR- 0.72 (0.62-0.83), DOR 3.56 (2.02-6.28), AUC 0.657. When the WHO subgroup was compared with the EIN subgroup, higher accuracy (AUC 0.694 vs. 0.621), and higher heterogeneity in all analyses, were observed.

CONCLUSIONS

Immunohistochemistry for PTEN showed low diagnostic usefulness in the differential diagnosis between benign and premalignant endometrial hyperplasia. In the absence of further evidence, the recommendation about its use should be reconsidered.

Assessing the prognostic value of PAX2 and PTEN in endometrial carcinogenesis

In order to avoid the consequences of over- and under-treatment of endometrial hyperplasia, diagnostic accuracy and progression risk assessment must be improved. The aim of this study was to assess whether PAX2 or PTEN expression could predict progression-free survival in endometrial intraepithelial neoplasia (EIN) and endometrial endometrioid carcinoma (EEC). Immunohistochemistry for detection of PAX2 and PTEN was performed on 348 endometrial samples; 75 proliferative endometrium (PE), 36 EIN and 237 EEC. Cases classified as PTEN null (1 or more glands negatively stained) were more prevalent in EEC than in PE and EIN (64% EEC vs 11% PE/EIN). A progressive decrease in PAX2 expression was observed from PE to EIN to EEC. Long-term clinical follow-up (6-310 months, median: 126) was available for 62 PE cases, all 36 EIN cases and 178 EEC cases. No patients with PE demonstrated progression to EIN or EEC. Progression of disease was observed in 10 (28%) EIN patients. These patients had significantly lower PAX2 expression than those that regressed (P = 0.005). Progression-free survival analysis revealed that EIN patients with a high-risk PAX2 expression score (H-score ≤75) had a higher probability of progression of disease in comparison to those with a low-risk score (H-score >75). PAX2 expression was not prognostic in EEC nor was PTEN status of prognostic value in either EIN or EEC. PAX2 expression analysis by means of H-score has prognostic potential for the identification of high-risk progression cases in EIN but needs to be validated in a larger cohort.

Combined treatment with artesunate and bromocriptine has synergistic anticancer effects in pituitary adenoma cell lines

Prolactinomas are the most prevalent functional pituitary adenomas. The preferred treatments for prolactinomas are dopamine agonists (DAs) such as bromocriptine (BRC), but DAs still have the challenges of tumor recurrence and drug resistance. This study demonstrates that the synergy of function and mechanism between artesunate (ART) and BRC inhibits prolactinoma cell growth in vitro. We found that low-dose ART combined with BRC synergistically inhibited the growth of GH3 and MMQ cell lines, caused cell death, attenuated cell migration and invasion, and suppressed the expression of extracellular prolactin. The induction of apoptosis after co-treatment was confirmed by immunofluorescent staining, assessment of caspase-3 protein expression, and flow cytometry. Expression of miR-200c, a carcinogenic factor in pituitary adenoma, was reduced following co-treatment with ART and BRC. This was accompanied by increased expression of the antitumor factor Pten. Transfection experiments with miR-200c analogs and inhibitors confirmed that miR-200c expression was inversely associated with Pten expression. We suggest that ART and BRC used in combination exert synergistic apoptotic and antitumor effects by suppressing miR-200c and stimulating Pten expression.

The clinical value and biological function of PTTG1 in colorectal cancer

Pituitary tumor transforming gene-1 (PTTG1) has been suggested to serve as an oncogene in several types of human tumors, but little is known about the biological function of PTTG1 in colorectal cancer. PTTG1 mRNA and protein expressions in colorectal cancer tissues and cell lines were measured by qRT-PCR, western blot or immunohistochemistry. The association between PTTG1 protein expression and clinicopathological features was analyzed. The function of PTTG1 on colorectal cancer cell proliferation and metastasis were explored through MTT, colony formation, migration and invasion assays. In our results, PTTG1 mRNA and protein expressions were increased in colorectal cancer tissues and cell lines compared with normal colonic tissues and colon epithelial cell line. PTTG1 overexpression positively associated with clinical stage, T classification, N classification, M classification and differentiation. The univariate and multivariate analyses suggested PTTG1 overexpression was an independent poor prognostic factor for colorectal cancer patients. The in vitro experiments showed knocking down PTTG1 inhibited colorectal cancer growth and metastasis. In conclusion, PTTG1 is an independent prognostic factor and acts as an oncogene in colorectal cancer.

Correlation of NEDD4-1 and PTEN expression with the invasive capacity of pituitary adenomas

The aim of the present study was to correlate the expression of neural precursor cell expressed developmentally downregulated 4-1 (NEDD4-1) and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) with the invasive capacity of pituitary adenomas. A total of 50 pituitary adenoma tissues and 10 normal pituitary tissues were divided into the invasive group (26 cases), the non-invasive group (24 cases) and the normal group (10 cases). The expression of NEDD4-1 and PTEN was determined by immunohistochemistry. NEDD4-1 was revealed to be located in the nucleus and cytoplasm, whereas PTEN was only located in the cytoplasm. Furthermore, expression of NEDD4-1 was higher in pituitary adenomas compared with normal pituitary tissues (P<0.05), and higher in the invasive group compared with the non-invasive group, whereas the opposite trend was observed for PTEN. There was a strong negative correlation between NEDD4-1 and PTEN expression, indicating a dependency between the two and an association with invasiveness. In conclusion, NEDD4-1 may serve as a diagnostic and prognostic factor, and as a novel therapeutic target, in pituitary adenomas.

Pituitary tumor transforming gene-1 in non-small cell lung cancer: Clinicopathological and immunohistochemical analysis

Pituitary tumor transforming gene-1 (PTTG1) is a novel oncogene and overexpressed in a wide variety of human cancers. However, the clinical and prognostic significance of PTTG1 in non-small cell lung cancer (NSCLC) is still unknown. The expression status of PTTG1 in NSCLC at the publicly available GEO databases (GSE19804) was observed. The mRNA and protein expression of PTTG1 in NSCLC tissues and cell lines was detected by qRT-PCR and Western blot, and the association between PTTG1 expression and clinicopathological factors was analyzed by immunohistochemistry. In our Results, PTTG1 was one of genes overexpressed in NCSLC samples compared with paired adjacent normal lung samples in microarray data (GSE19804). PTTG1 mRNA and protein expressions were increased in NSCLC tissues and cell lines. PTTG1 protein expression was correlated with malignant status and poor prognosis of NSCLC patients. In conclusion, PTTG1 is correlated with NSCLC progression and as an independent poor prognostic factor in NSCLC patients.

Features of omental adipose tissue in endometrial cancer patients with 'standard' or 'metabolically healthy' obesity: associations with tumor process characteristics

Purpose

Adipose tissue products may contribute to endometrial cancer (EC) initiation and further growth that encourages the analysis of this issue in patients with different obesity phenotypes.

Methods/patients

Omental fat depot characteristics were studied in EC patients (n = 57) with “standard” (SO) or “metabolically healthy” (MHO) obesity. Collected omental samples were evaluated by immunohistochemistry /IHC/ for brown fat marker UCP1, CYP19 (aromatase) and macrophage infiltration markers (CD68, CD163, crown-like structures/CLS) expression. Total RNA extracted from the same samples was investigated for UCP1, CYP19, PTEN and adipokine omentin mRNA.

Results

Immunohistochemistry data revealed a statistically significant increase in aromatase and CD68 expression and tendency to increase of UCP1 expression in SO patients’ omental fat compared to samples obtained from MHO patients. Additionally, positive correlation of EC clinical stage with UCP1 protein and its mRNA content in omental fat was pronounced in MHO as well as SO group, while with omentin mRNA it was discovered only in patients with SO. An inclination to the correlation with better tumor differentiation was seen for UCP1 and CD68 protein expression in patients with MHO and with worse (high grade) differentiation—for CD68 expression in the group with SO.

Conclusions

In aggregate, this suggests that obesity phenotype has significant impact on omental fat tissue characteristics which is related to the clinical course of EC and may have practical consequences.

mTOR promotes pituitary tumor development through activation of PTTG1

As one of the most common intracranial tumors, pituitary tumor is associated with high morbidity. Effective therapy is currently not available for some pituitary tumors due to the largely undefined pathological processes of pituitary tumorigenesis. In this study, hyperactivation of mammalian/mechanistic target of rapamycin (mTOR) signaling was observed in estrogen-induced rat pituitary tumor and mTOR inhibitor rapamycin blocked the tumor development. Pituitary knockout of either mTOR signaling pathway negative regulator Tsc1 or Pten caused mouse pituitary prolactinoma, which was abolished by rapamycin treatment. Mechanistically, the expression of pituitary tumor transforming gene 1 (PTTG1) was upregulated in an mTOR complex 1-dependent manner. Overexpressed PTTG1 was crucial in hyperactive mTOR-mediated tumorigenesis. mTOR-PTTG1 signaling axis may be targeted for the treatment of tumors with mTOR hyperactivation.

Expression of PTEN and β-Catenin and Their Relationship With Clinicopathological and Prognostic Factors in Endometrioid Type Endometrial Cancer

OBJECTIVE

The aim of this study was to investigate rates of expression of PTEN (phosphatase and tensin homolog deleted on chromosome 10) and β-catenin and their relationship with clinicopathological and prognostic factors in endometrioid type endometrial cancer (EC).

METHODS AND MATERIALS

PTEN and β-catenin expressions of 59 operated patients with EC between January 2000 and December 2008 and followed-up until December 2014 in Cerrahpasa School of Medicine, Gynecologic Oncology Division, were evaluated retrospectively. Clinical data were obtained from patient files, and pathological data were obtained from pathology records. Each patient had 4 paraffin sections of tumoral tissue. These sections were stained by immunohistochemical methods. Clinical features and postoperative histopathologic findings were analyzed using Fisher exact test or the χ(2) test as appropriate. The Kaplan-Meier method was used to generate the survival curves.

RESULTS

During median follow-up of 102 months, tumor recurrence and disease-related mortality were observed in 10 (16.9%) and 7 (11.9%) cases, respectively. Immunohistochemical staining of PTEN and β-catenin were positive in 61% and 69.5% of all cases, respectively. Positive staining of PTEN was positively correlated with myometrial invasion (P= 0.02). There was no correlation between β-catenin and clinicopathological factors. PTEN or β-catenin positivity were not significant prognostic factors for 5-year overall survival (P = 0.37, P = 0.62, respectively) and 5-year disease-free survival (P = 0.28, P = 0.58, respectively).

CONCLUSIONS

PTEN and β-catenin expressions cannot be used to determine prognosis in patients with EC as PTEN and β-catenin staining status were found to have no significant effect on 5-year overall survival and disease-free survival. Positive staining of PTEN may be associated with increased myometrial invasion. Meta-analyses and broader studies are needed to evaluate the prognostic value of PTEN and β-catenin in EC.

MicroRNA involvement in a metastatic non-functioning pituitary carcinoma

PURPOSE

Pituitary carcinomas are extremely rare neoplasms, and molecular events leading to malignant pituitary transformation are largely unknown. Enhanced understanding of molecular mechanisms driving malignant pituitary progression would be beneficial for pituitary carcinoma diagnosis and treatment.

METHODS

Differential microRNA expression in paired primary and metastatic pituitary carcinoma specimens were detected using high-throughput human microRNA microarrays and TaqMan microRNA arrays. Three of significantly deregulated miRNAs were further confirmed using quantitative real-time PCR in the metastatic carcinoma, six atypical pituitary adenomas and eight typical pituitary adenomas. Target genes of microRNAs were bioinformatically predicated and verified in vitro by Western blotting and real-time PCR and in vivo by immunohistochemistry respectively.

RESULTS

We present a case of a 50-year-old woman harboring non-functioning pituitary carcinoma with multiple intracranial metastases, and identified up-regulation of miR-20a, miR-106b and miR-17-5p in the metastatic carcinoma as compared to the primary neoplasm. Furthermore, miR-20a and miR-17-5p were increased in the metastatic carcinoma and six atypical pituitary adenomas as compared to eight typical pituitary adenomas as measured by quantitative real-time PCR. Both PTEN and TIMP2 were bioinformatically predicated and confirmed in vitro as target genes of these three microRNAs. As semi-quantified by immunohistochemistry, PTEN was absent and TIMP2 was decreased in the metastatic pituitary carcinoma as compared to pituitary adenomas.

CONCLUSIONS

Our results suggest microRNA involvement in malignant pituitary progression, whereby increased miR-20a, miR-106b and miR-17-5p promote metastasis by attenuating PTEN and TIMP2 in pituitary carcinoma.

PTEN expression in benign human endometrial tissue and cancer in relation to endometrial cancer risk factors

PURPOSE

Clonal loss of PTEN expression occurs frequently in endometrial carcinoma and endometrial hyperplasia. Limited data from immunohistochemical studies suggest that PTEN-null appearing endometrial glands are detectable in women without pathologic abnormalities, but the relationship of PTEN expression to endometrial cancer risk factors has not been extensively explored. We evaluated relationships between endometrial cancer risk factors and loss of PTEN expression in a set of benign endometrial samples prospectively collected from women undergoing hysterectomy and in endometrial cancer tissues from a population-based case-control study.

METHODS

We used a validated PTEN immunohistochemical assay to assess expression in epidemiological studies designed to assess benign endometrium [Benign Reproductive Tissue Evaluation Study (n = 73); Einstein Endometrium Study (n = 19)], and endometrial cancer [Polish Endometrial Cancer Study (n = 148)] tissues. Associations between endometrial cancer risk factors (collected via study-specific risk factor questionnaires) and PTEN expression in endometrial tissues were determined using Fisher's exact tests.

RESULTS

PTEN loss was detected in 19% of benign endometrial tissues versus 55% in endometrial cancers. NSAID use was statistically significantly associated with PTEN loss in the benign endometrium (p = 0.02).

CONCLUSION

Our data demonstrate that PTEN loss is detectable in endometrial tissues that are benign and malignant, with substantially more frequent loss in endometrial cancer compared with benign endometrium. However, alterations in expression were unrelated to most risk factors in this analysis, except for the association with NSAID use, which may represent a chance finding or reverse causality among patients with endometriosis who may have PTEN pathway abnormalities in eutopic endometrium. Further evaluation of factors associated with PTEN loss and long-term follow-up of women with PTEN-null endometrial glands may be useful in understanding early events in endometrial carcinogenesis.

TWIST and ovarian cancer stem cells: implications for chemoresistance and metastasis

The transcription factor TWIST1 is a highly evolutionally conserved basic Helix-Loop-Helix (bHLH) transcription factor that functions as a master regulator of gastrulation and mesodermal development. Although TWIST1 was initially associated with embryo development, an increasing number of studies have shown TWIST1 role in the regulation of tissue homeostasis, primarily as a regulator of inflammation. More recently, TWIST1 has been found to be involved in the process of tumor metastasis through the regulation of Epithelial Mesenchymal Transition (EMT). The objective of this review is to examine the normal functions of TWIST1 and its role in tumor development, with a particular focus on ovarian cancer. We discuss the potential role of TWIST1 in the context of ovarian cancer stem cells and its influence in the process of tumor formation.

Knockdown of PTTG1 inhibits the growth and invasion of lung adenocarcinoma cells through regulation of TGFB1/SMAD3 signaling

Increased expression of pituitary tumor-transforming gene 1 (PTTG1) is expressed in many tumors and regulates tumor growth and progression. However, the precise function of PTTG1 in the tumorigenesis of lung adenocarcinoma (LAC) is not defined yet. Here, we examined the expression of PTTG1 in human LAC tissues by immunohistochemical assay using a tissue microarray procedure. A loss-of-function experiment was carried out to investigate the effects of lentiviral vector-mediated PTTG1 shRNA (shPTTG1) on cell growth and invasive potential in LAC cell lines (A549 and LETPα-2), assessed by MTT and Transwell assays. As a consequence, we found that the expression of PTTG1 protein was markedly upregulated in LAC tissues compared with the adjacent non-cancerous tissues (ANCT) (54.0% vs. 28.0%, P = 0.008), and was positively associated with the lymphatic invasion of the tumor ( P = 0.01). Moreover, knockdown of PTTG1 expression inhibited tumor proliferation and invasion of LAC cells, companied by the decreased expression of CyclinD1 and MMP-2 and increased expression of p-TGFβ1 and p-SMAD3. Collectively, our findings indicate that high expression of PTTG1 is correlated with the tumor metastasis of LAC patients, and knockdown of PTTG1 suppresses the growth and invasion of LAC cells through upregulation of the TGFβ1/SMAD3 signaling, suggesting that PTTG1 may be a potential target for developing an effective immunotherapeutic strategy for LAC.

High expression of pituitary tumor-transforming gene-1 predicts poor prognosis in clear cell renal cell carcinoma

Pituitary tumor-transforming gene-1 (PTTG1) is a recently identified oncogene involved in the progression of malignant tumors; however, the expression level of PTTG1 in clear cell renal cell carcinoma (ccRCC) and its potential value as a novel prognostic marker for ccRCC remains unclear. In this study, PTTG1 mRNA and protein levels were assessed in 44 paired ccRCC tissues and adjacent normal tissues by quantitative polymerase chain reaction (qPCR) and immunohistochemistry, respectively. Further immunohistochemical analysis was implemented in 192 samples of ccRCC to evaluate the associations between PTTG1 levels and the clinical characteristics in ccRCC. Reverse transcription qPCR and immunohistochemical analysis demonstrated that the PTTG1 mRNA and protein levels were significantly higher in ccRCC compared to normal tissues. In addition, the PTTG1 protein level in 192 ccRCC samples was found to be significantly correlated with T stage, N classification, metastasis, recurrence and Fuhrman grade, whereas it was not associated with age and gender. Patients with low PTTG1 levels exhibited a better survival outcome compared to those with a higher PTTG1 level. PTTG1 expression and N stage were identified as independent prognostic factors for the overall survival of ccRCC patients. The results suggested that the overexpression of PTTG1 indicates a poor prognosis in ccRCC patients and, therefore, PTTG1 may serve as a novel prognostic marker for ccRCC.

Phosphatase and tensin homolog overexpression decreases proliferation and invasion and increases apoptosis in oral squamous cell carcinoma cells

Phosphatase and tensin homolog (PTEN) is a potent tumor suppressor which regulates various cellular functions. The aim of the present study was to analyze the function of PTEN gene expression in squamous cell carcinoma (SCC) cells. This gene exhibits a unique function in cell migration and proliferation during the early stages of embryonic development. However, its role as a tumor suppressor gene in tongue squamous carcinoma cells remains unclear. In the present study, an SCC-4 cell line stably expressing PTEN was established and the effects of PTEN gene expression on SCC-4 cell proliferation, invasion and apoptosis were investigated. PTEN expression was found to induce apoptosis in SCC-4 cells, possibly via negative regulation of the phosphatidylinositide 3-kinase/Akt signaling pathway and increased expression of Bcl-2-interacting mediator of cell death. In addition, PTEN was found to control the epithelial-mesenchymal transition in SCC cells, thereby reducing their invasive ability. Furthermore, Transwell assay revealed that the expression of E-cadherin was increased, while the expression of vimentin and SNAIL was decreased. This study has provided an important insight into the mechanisms by which PTEN mediates the progression and early metastasis of tongue carcinoma.