Expression of survivin in esophageal cancer: correlation with the prognosis and response to chemotherapy

Survivin as a Therapeutic Target for the Treatment of Human Cancer

Survivin was initially identified as a member of the inhibitor apoptosis (IAP) protein family and has been shown to play a critical role in the regulation of apoptosis. More recent studies showed that survivin is a component of the chromosome passenger complex and acts as an essential mediator of mitotic progression. Other potential functions of survivin, such as mitochondrial function and autophagy, have also been proposed. Survivin has emerged as an attractive target for cancer therapy because its overexpression has been found in most human cancers and is frequently associated with chemotherapy resistance, recurrence, and poor survival rates in cancer patients. In this review, we discuss our current understanding of how survivin mediates various aspects of malignant transformation and drug resistance, as well as the efforts that have been made to develop therapeutics targeting survivin for the treatment of cancer.

Is the serum level of survivin, an antiapoptotic protein, a potential predictive and prognostic biomarker in metastatic pancreatic cancer?

In the present study, we aimed to assess the association between the serum survivin level and overall survival and treatment response rates in metastatic pancreatic cancer (MPC). Serum samples were prospectively collected from 41 patients with newly diagnosed MPC patients and 41 healthy individuals (control group) to assess the survivin levels. The median survivin level was 136.2 ng/mL in patients with MPC and 52 ng/mL in healthy individuals (P = .028). Patients were divided into low- and high-survivin groups according to the baseline median survivin level. Patients with a high serum survivin level compared with a low serum survivin level had shorter median progression-free survival (2.39 vs 7.06 months; P = .008, respectively) and overall survival (3.74 vs 9.52 months; P = .026, respectively). Patients with higher serum survivin levels had significantly worse response rates (P = .007). The baseline high level of serum survivin in patients with MPC may be associated with treatment resistance and poor prognosis. A confirmation will be needed for these results in future large multicenter prospective studies.

Pan-cancer analysis reveals the prognostic and immunotherapeutic value of cytoskeleton-associated protein 2-like

Cytoskeleton-associated protein 2-like (CKAP2L), a cell cycle-related protein, is correlated to tumor progression in some tumors. But there were no pan-cancer studies on CKAP2L, and its role in cancer immunotherapy is also unclear. The expression levels, expression activity, genomic alterations, DNA methylation and functions of CKAP2L in various tumors, as well as the associations between CKAP2L expression and patient prognosis, chemotherapy sensitivity, and tumor immune microenvironment, were all analyzed in a comprehensive pan-cancer analysis of CKAP2L by various databases, analysis websites, and R software. The experiments were also conducted to verify the analysis results. In the majority of cancers, CKAP2L expression and activity were markedly elevated. Elevated CKAP2L expression led to poor prognostic outcomes in patients, and is an independent risk factor for most tumors. Elevated CKAP2L causes decreased sensitivity to chemotherapeutic agents. Knockdown of CKAP2L significantly inhibited the proliferation and metastasis capacity of the KIRC cell lines and resulted in cell cycle G2/M arrest. In addition, CKAP2L was closely related to immune subtypes, immune cell infiltration, immunomodulators and immunotherapy markers (TMB, MSI), patients with high CKAP2L expression were more sensitive to immunotherapy in the IMvigor210 cohort. The results indicate that CKAP2L is a pro-cancer gene that serves as a potential biomarker for predicting patient outcomes. By inducing cells to transition from the G2 phase to the M phase, CKAP2L may promote cell proliferation and metastasis. Furthermore, CKAP2L is closely related to the tumor immune microenvironment and can be used as a biomarker to predict tumor immunotherapy.

An Insight into Survivin in Relevance to Hematological, Biochemical and Genetic Characteristics in Tobacco Chewers with Oral Squamous Cell Carcinoma

BACKGROUND

Survivin is an inhibitor of apoptosis protein (IAP), encoded by the Baculoviral IAP Repeat Containing 5 (BIRC5) gene located on q arm (25.3) on chromosome 17. It is expressed in various human cancers and involved in tumor resistance to radiation and chemotherapy. The genetic analysis of the BIRC5 gene and its protein survivin levels in buccal tissue related to oral squamous cell carcinoma (OSCC) in South Indian tobacco chewers has not been studied. Hence, the study was designed to quantify survivin in buccal tissue and its association with pretreatment hematological parameters and to analyze the BIRC5 gene sequence.

METHOD

In a single centric case control study, buccal tissue survivin levels were measured by ELISA. A total of 189 study subjects were categorized into Group 1 (n = 63) habitual tobacco chewers with OSCC, Group 2 (n = 63) habitual tobacco chewers without OSCC, and Group 3 (n = 63) healthy subjects as control. Retrospective hematological data were collected from Group 1 subjects and statistically analyzed. The BIRC5 gene was sequenced and data were analyzed using a bioinformatics tool.

RESULTS

Survivin protein mean ± SD in Group 1 was (1670.9 ± 796.21 pg/mL), in Group 2 it was (1096.02 ± 346.17 pg/mL), and in Group 3 it was (397.5 ± 96.1 pg/mL) with significance (p < 0.001). Survivin levels showed significance with cut-off levels of absolute monocyte count (AMC), neutrophil/lymphocyte ratio (NLR), and lymphocyte/monocyte ratio (LMR) at (p = 0.001). The unique variants found only in OSCC patients were T → G in the promoter region, G → C in exon 3, C → A, A → G, G → T, T → G, A → C, G → A in exon 4, C → A, G → T, G → C in the exon 5 region.

CONCLUSIONS

The tissue survivin level increased in OSCC patients compared to controls; pretreatment AMC, LMR, and NLR may serve as add-on markers along with survivin to measure the progression of OSCC. Unique mutations in the promoter and exons 3-5 were observed in sequence analysis and were associated with survivin concentrations.

FBXL7 Body Hypomethylation Is Frequent in Tumors from the Digestive and Respiratory Tracts and Is Associated with Risk-Factor Exposure

Squamous cell carcinoma is the main histological tumor type in the upper aerodigestive tract (UADT), including the esophagus (ESCC) and the head and neck sites, as well as the oral cavity (OCSCC), larynx (LSCC) and oropharynx (OPSCC). These tumors are induced by alcohol and tobacco exposure, with the exception of a subgroup of OPSCC linked to human papillomavirus (HPV) infection. Few genes are frequently mutated in UADT tumors, pointing to other molecular mechanisms being involved during carcinogenesis. The F-box and leucine-rich repeat protein 7 (FBXL7) is a potential tumor-suppressing gene, one that is frequently hypermethylated in pancreatic cancer and where the encoded protein promotes the degradation of AURKA, BIRC5 and c-SRC. Thus, the aim of this study was to evaluate the methylation and expression profile of FBXL7 in the UADT and the gene’s association with the clinical, etiological and pathological characteristics of patients, as well as the expression of its degradation targets. Here we show that the FBXL7 gene’s body is hypomethylated in the UADT, independently of histology, but not in virus-associated tumors. FBXL7 body methylation and gene expression levels were correlated in the ESCC, LSCC, OCSCC and OPSCC. Immunohistochemistry analysis showed that FBXL7 protein levels are not correlated with the levels of its degradation targets, AURKA and BIRC5, in the UADT. The high discriminatory potential of FBXL7 body hypomethylation between non-tumor and tumor tissues makes it a promising biomarker.

Molecular mechanism, regulation, and therapeutic targeting of the STAT3 signaling pathway in esophageal cancer (Review)

Esophageal cancer (EC) is the seventh most common cancer globally, and the overall 5-year survival rate is only 20%. Signal transducer and activator of transcription 3 (STAT3) is aberrantly activated in EC, and its activation is associated with a poor prognosis. STAT3 can be activated by canonical pathways such as the JAK/STAT3 pathway as well as non-canonical pathways including the Wnt/STAT3 and COX2/PGE2/STAT3 pathways. Activated STAT3, present as phosphorylated STAT3 (p-STAT3), can be transported into the nucleus to regulate downstream genes, including VEGF, cyclin D1, Bcl-xL, and matrix metalloproteinases (MMPs), to promote cancer cell proliferation and induce resistance to therapy. Non-coding RNAs, including microRNAs (miRNAs/miRs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs), play a vital role in regulating the STAT3 signaling pathway in EC. Several miRNAs promote or suppress the function of STAT3 in EC, while lncRNAs and circRNAs primarily promote the effects of STAT3 and the progression of cancer. Additionally, various drugs and natural compounds can target STAT3 to suppress the malignant behavior of EC cells, providing novel insights into potential EC therapies.

Co-expression of VEGF-C and survivin predicts poor prognosis in esophageal squamous cell carcinoma

BACKGROUND

Lymphatic metastasis is one of the main factors affecting prognosis in esophageal squamous cell carcinoma (ESCC). Vascular endothelial growth factor-C (VEGF-C) is an important factor that promotes lymphangiogenesis. Survivin also plays a significant role in lymphatic invasion. However, the role and mechanism of their co-expression are still unclear in ESCC. The purpose of this study was to investigate whether the co-expression of VEGF-C and survivin could be a potential marker to predict patient prognosis and survival in ESCC.

METHODS

The levels of VEGF-C, vascular endothelial growth factor receptor 3 (VEGFR-3), survivin, and Ki-67 were determined by immunohistochemistry (IHC) in 97 ESCC patient tumors. The correlations of co-expression of VEGF-C and survivin with pathological features and survival results were also assessed.

RESULTS

High VEGF-C expression was observed in 64.9% of the patients and significantly correlated with T stage (P=0.024), node status (P=0.038), and lymph node metastasis (P=0.015). High survivin expression was significantly associated with T stage (P=0.013), N stage (P=0.016), lymph node metastasis (P=0.005), and differentiation (P=0.044) in 67.0% of the patients. Co-expression of VEGF-C and survivin (V+S+) was significantly associated with T stage (P<0.001), N stage (P=0.015), lymph node metastasis (P=0.003), differentiation (P=0.0045), and Ki-67 levels (P=0.024). High expression of VEGF-C or survivin was associated significantly with worse disease-free survival (DFS) and overall survival (OS) (P<0.05). Moreover, the V+S+ group had a worse DFS (P<0.001) and OS (P=0.001) than any other group (i.e., V-S-, V+S-, V-S+). Furthermore, multivariate DFS analyses (95% CI: 1.147-2.220, P=0.006) and multivariate OS analyses (95% CI: 1.080-2.193, P=0.017) revealed that co-expression of VEGF-C and survivin was an independent prognostic factor in ESCC patients.

CONCLUSIONS

Co-expression of VEGF-C and survivin was predictive of poor prognosis in ESCC. Combined detection of VEGF-C and survivin could represent a feasible and effective marker to predict the prognosis and survival of ESCC patients.

Nucleic acids therapeutics using PolyPurine Reverse Hoogsteen hairpins

PolyPurine Reverse Hoogsteen hairpins (PPRHs) are DNA hairpins formed by intramolecular reverse Hoogsteen bonds which can bind to polypyrimidine stretches in dsDNA by Watson:Crick bonds, thus forming a triplex and displacing the fourth strand of the DNA complex. PPRHs were first described as a gene silencing tool in vitro for DHFR, telomerase and survivin genes. Then, the effect of PPRHs directed against the survivin gene was also determined in vivo using a xenograft model of prostate cancer cells (PC3). Since then, the ability of PPRHs to inhibit gene expression has been explored in other genes involved in cancer (BCL-2, mTOR, topoisomerase, C-MYC and MDM2), in immunotherapy (SIRPα/CD47 and PD-1/PD-L1 tandem) or in replication stress (WEE1 and CHK1). Furthermore, PPRHs have the ability to target the complementary strand of a G-quadruplex motif as a regulatory element of the TYMS gene. PPRHs have also the potential to correct point mutations in the DNA as shown in two collections of CHO cell lines bearing mutations in either the dhfr or aprt loci. Finally, based on the capability of PPRHs to form triplexes, they have been incorporated as probes in biosensors for the determination of the DNA methylation status of PAX-5 in cancer and the detection of mtLSU rRNA for the diagnosis of Pneumocystis jirovecii. Of note, PPRHs have high stability and do not present immunogenicity, hepatotoxicity or nephrotoxicity in vitro. Overall, PPRHs constitute a new economical biotechnological tool with multiple biomedical applications.

Expression and clinical correlation of Survivin and PTEN in gastric cancer patients

Reports on the correlation between the expression of Survivin/phosphatase and tensin homolog (PTEN) proteins and clinical factors in gastric cancer (GC) are varied, and the sample sizes were also not sufficient. The present study aimed to detect the expression of Survivin and PTEN proteins in GC patients on the basis of a greater number of specimens and to analyze the correlation with clinical features and survival. The results revealed that the Survivin expression rates in GC, normal tissues and metastatic lymph nodes were 72% (232/322), 5% (6/120) and 80% (36/45), respectively, while the PTEN expression rates were 34% (109/322), 92.5% (111/120) and 24.4% (11/45), respectively, and the differences between cancer and normal tissue or metastatic lymph nodes were significant for both proteins (P<0.05). The expression of Survivin was significantly associated with gross type, depth of invasion, distant metastasis, tumor, necrosis and metastasis (TNM) stage and vascular invasion, while PTEN expression was predominantly associated with age, tumor size, invasion depth, TNM stage and lymphatic invasion in GC patients (P<0.05). The expression of both was associated with postoperative metastasis and metastatic site (P=0.007 and P=0.011 for Survivin, and P=0.002 and P=0.005 for PTEN). There was a negative association between the expression levels of Survivin and PTEN (P=0.001, r=−0.524). The expression levels of both were also associated with prognosis. The expression of Survivin and PTEN protein exhibit opposing trends in GC, which may indicate adverse biological effects in the occurrence of GC. The Survivin and PTEN expression levels are likely to be an important molecular event in gastric tumorigenesis and may be considered as molecular markers of GC progression and reliable prognostic indicators of GC.

Molecular mechanisms underlying rheumatoid arthritis and cancer development and treatment

Given recent advances in cancer immune therapy, specifically use of checkpoint inhibitors, understanding the link between autoimmunity and cancer is essential. Rheumatoid arthritis (RA) affects about 1% of the population, and early diagnosis is key to prevent joint damage. Management consists of disease-modifying antirheumatic drugs that alter normal immunologic pathways, which could affect malignancy growth and survival. Prolonged immune dysregulation and the resulting inflammatory response associated with development of RA may also lead to increased cancer development risk. RA has long been associated with increased risk of non-Hodgkin's lymphoma [1] and further evidence supports relationship to lung cancer [2]. This review will address the mechanisms behind cancer development and progression in RA patients, biomarkers and assess cancer risk and early detection.

Bosutinib Acts as a Tumor Inhibitor via Downregulating Src/NF-κB/Survivin Expression in HeLa Cells

Efforts have been made to find effective medical drugs for cervical cancer treatment. The incidence of cervical cancer ranks second among women, and is a serious threat to women's health. Aberrant activation of the nonreceptor protein tyrosine kinases such as Src is commonly observed in progressive stages of human tumors. Thus, targeting Src kinase could be a promising strategy for cervical cancer therapy. In this study, we explored the potential utility of bosutinib in the treatment of cervical cancer. We found that bosutinib, as a potent dual Src/Abl inhibitor, could exert anti-tumor effects on cervical cancer. Bosutinib inhibited cervical cancer cells proliferation and colony formation ability in a dose-dependent manner, and also induced apoptosis. Mechanistically, bosutinib effectively decreased the activity of Src/NF-κB/survivin signaling pathway. Our study provided a biological rationale to test bosutinib as a valuable therapeutic option for cervical cancer patients. Anat Rec, 302:2193-2200, 2019. © 2019 American Association for Anatomy.

The expression of survivin in irreversible pulmonary arterial hypertension rats and its value in evaluating the reversibility of pulmonary arterial hypertension secondary to congenital heart disease

The reversibility of pulmonary arterial hypertension (PAH) determines the operability of congenital heart disease (CHD) complicating with PAH, but it lacks a method for evaluating the reversibility. The current study aims to investigate the serum survivin level in irreversible PAH rats and to explore its potential as a biomarker for evaluating the reversibility of PAH in CHD patients. Irreversible PAH rats were characterized by prominent obstructive lesions resulting from the intimal formation, which was associated with decreased apoptosis and increased survivin expression, while reversible PAH rats were featured by medial hypertrophy resulting in mild occlusion, with increased apoptosis and unchanged survivin expression. In addition, the serum survivin was significantly increased in irreversible PAH rats when compared to both reversible PAH and control rats, and a positive correlation of serum survivin with survivin expression in the lung was confirmed. Third, the preoperative serum survivin was significantly higher in patients with irreversible CHD-PAH than in these with reversible CHD-PAH, and significant correlations between the serum survivin and BNP, preoperative pulmonary vascular resistance index, and postoperative mean pulmonary arterial pressure were also identified. In conclusion, the increased survivin level is a feature of irreversible PAH and the serum survivin represents a candidate biomarker reflecting the operability of CHD-PAH patients.

Effects of gossypol on apoptosis‑related gene expression in racially distinct triple‑negative breast cancer cells

Apoptosis is a gene‑directed mechanism that regulates cell proliferation and maintains homeostasis. Moreover, an aberrant apoptotic process can lead to several pathological conditions, such as tumorigenesis and cancer metastasis. In the present study, the apoptotic effect of the natural polyphenol compound gossypol GOSS) was investigated in triple‑negative breast cancer TNBC) cells. The effect of GOSS was evaluated in two cell lines representative of a Caucasian‑American and African‑American origin, MDA‑MB‑231 MM‑231) and MDA‑MB‑468 MM‑468), respectively. A similar response to both cytotoxicity and proliferation was observed in the two cell lines. However, MM‑468 cells were 2‑fold more sensitive to the apoptotic effect of the compound, which was accompanied by a longer delay in colony formation. Furthermore, GOSS was found to alter the mRNA expression of many apoptosis‑related genes. The compound significantly upregulated growth arrest and DNA damage‑inducible 45 alpha protein (GADD45A), tumor necrosis factor receptor superfamily 9 (TNFRSF9) and BCL2 interacting protein 3 BNIP3) in MM‑231 cells. Similarly, GADD45A and BNIP3 were upregulated in MM‑468 cells. A significant finding in this study is the profound 159‑fold increase in TNF gene expression that was observed in MM‑468 cells. Moreover, the apoptosis‑suppressor gene baculoviral IAP repeat containing 5 BIRC5) was significantly repressed (by more than 90%) in both cell lines, as well as death‑associated protein kinase 1 (DAPK1) in MM‑231 cells and tumor protein 73 (TP73) in MM‑468 cells. In conclusion, the data obtained in this study provide a molecular understanding of the GOSS‑induced apoptosis effect and suggest the importance of this polyphenol compound targeted towards TNBC treatment, particularly in African‑American women.

CCN1 induces apoptosis in esophageal adenocarcinoma through p53-dependent downregulation of survivin

Many cancer drugs have been developed to control tumor growth by inducing cancer cell apoptosis. However, several intracellular barriers could fail this attempt. One of these barrier is high expression of survivin. Survivin can interfere caspase activation and thereby abort apoptosis. In this study, we found that CCN1 suppressed the survivin expression in tumor cells of esophageal adenocarcinoma (EAC) and thus allowed apoptosis to finish. Furthermore, we demonstrated that this downregulation was dependent on p53 phosphorylation at Ser20, and CCN1 induced EAC cell apoptosis through the activation of p53.

Marked Inhibition of Cellular Proliferation in the Normal Human Esophageal Epithelial Cells and Human Esophageal Squamous Cancer Cells in Culture by Carotenoids: Role for Prevention and Early Treatment of Esophageal Cancer

Background:

Globally Esophageal cancer is a common cancer arising from human esophageal mucosal tissue. Epidemiological studies suggest inverse correlation between carotenoid intake and incident risk of this devastating malignancy.

Methods:

In an effort to examine the modulatory role of carotenoids in human esophageal carcinogenesis at a cellular level, we examined the effects of α-carotene and β-carotenes, on cell proliferation and DNA synthesis in human esophageal epithelial (HEE) cells and human esophageal squamous cancer (HESC) cells in in-vitro cultures. HEE and HESC cells were incubated with different concentrations of α- and β-carotenes both individually and in combination.

Results:

Both Carotenes significantly inhibited (p<0.05) cellular proliferation and decreased DNA synthesis in HEE and HESC cells. The effect of α- and β-carotene together on DNA synthesis in HEE and HESC cells was significantly greater than either carotenoid alone, suggesting a synergistic effect. Greater magnitude of cellular inhibition of DNA synthesis was observed on HEE cells than HESC cells.

Conclusion:

Our results suggest that a combination of α-and β-carotene may provide a novel strategy for prevention and treatment of esophageal and upper aero digestive tract cancer in humans.

Identification of miRNA profiling in prediction of tumor recurrence and progress and bioinformatics analysis for patients with primary esophageal cancer: Study based on TCGA database

OBJECT

This study focused on the identification of prognostic miRNAs for the prediction of tumor recurrence and progress in esophageal cancer.

METHODS

MiRNA profiling and clinical characteristics of esophageal cancer patients was downloaded from the TCGA database. Univariate analysis was performed to select potential prognostic miRNAs and covariates. LASSO based logistic regression was conducted to identify the prognostic miRNAs given covariates. Bioinformatics analysis including gene ontology, disease ontology and pathway enrichment analysis were performed. A nomogram was generated based on multivariate logistic regression to illustrate the association between the identified miRNAs and the risk of tumor recurrence and progress.

RESULTS

A total of 1881 miRNAs and 10 clinical characteristics were obtained from TCGA database. 18 miRNAs were finally identified in which 6 miRNAs were identified for the first time to be associated with the tumor recurrence and progress of esophageal cancer given covariates. Bioinformatics analysis suggested that the identified miRNAs were associated with the tumor recurrence and progress of esophageal cancer. The association between identified miRNAs and risk of tumor recurrence and progress were presented in a nomogram.

CONCLUSION

The 6 newly identified miRNAs may be potential biomarkers for the prediction of tumor recurrence and progress of esophageal cancer.

Growth inhibition and chemo-radiosensitization of esophageal squamous cell carcinoma by survivin-shRNA lentivirus transfection

Esophageal cancer is one of the most common types of cancer worldwide, and it has a poor prognosis. Chemo-radiotherapy resistance and cancer relapse are among the most difficult issues in its treatment. Identifying the underlying molecular mechanisms is critical for developing novel therapies. Survivin has been previously suggested to be overexpressed in esophageal cancer cells. The present study identified that down-regulation of survivin sensitized esophageal cancer cells to chemo-radiotherapy. Consistent with previous studies, the present study indicated that survivin was overexpressed in 4 esophageal squamous carcinoma cell lines. Short hairpin RNA delivered by lentivirus successfully knocked down survivin in these cancer cell lines. Consequently, down-regulation of survivin impaired their colony-forming, migratory and invasive capabilities, while the overexpression of survivin in normal human esophagus epithelial cells improved their resistance to cisplatin, paclitaxel and radiation. Survivin knockdown induced apoptosis in esophageal cancer KYSE-150 and ECA-109 cell lines when exposed to the aforementioned chemo-radiotherapy treatments. These results indicate that survivin expression sustains growth in esophageal cancer cells, and confers resistance to chemo-radiotherapy. Targeted survivin ablation may be a promising strategy against esophageal tumor relapse and chemo-radioresistance.

Downregulation of BIRC5 inhibits the migration and invasion of esophageal cancer cells by interacting with the PI3K/Akt signaling pathway

As a mitotic spindle checkpoint gene, baculoviral IAP repeat containing 5 (BIRC5) serves pivotal roles in the development of various types of malignant tumors. In the present study, the expression of BIRC5 in patients with different stages of esophageal squamous cell cancer (ESCC) was investigated. The effect of BIRC5 on the migratory and invasive abilities of different ESCC cell lines was analyzed. Additionally, the effect of BIRC5 on the angiogenesis-associated factor vascular endothelial growth factor, brain-specific angiogenesis inhibitor 1 and methyl-CpG binding domain protein 2 was examined. In addition, the interaction between BIRC5 and the phosphatidylinositol 3-kinase (PI3K)/Akt pathway was analyzed. It was determined that BIRC5 is able to inhibit the migration and invasion of tumor cells, and regulate the expression of angiogenesis-associated factors. In addition, the PI3K/Akt signaling pathway is able to regulate the expression of BIRC5, which affects the development of ESCC.

In vivo antitumor activity of liposome‑plasmid DNA encoding mutant survivin‑T34A in cervical cancer

The aim of the present study was to investigate the influence of liposome-plasmid encoding mutant survivin-T34A (PST34A) on tumor growth in cervical cancer in vivo. Liposome-plasmid DNA encoding mutant survivin-T34A was constructed and administered via an intraperitoneal injection in mice inoculated with cervical cancer cells. Following the establishment of the tumor model, the animals were randomly divided into four groups: i) The normal saline group (NS; 100 µl sterile saline once/3 days for 15 days); ii) the 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) control (100 µg DOTAP once/3 days for 15 days); iii) the plasmid PST34A (10 µg PST34A once/3 days for 15 days); and iv) the PST34A+DOTAP (10 µg PST34A+100 µg DOTAP once/3 days for 15 days). All treatments were administered via intraperitoneal injections. Tumor growth was evaluated following injection with liposome-plasmid DNA encoding mutant survivin-T34A. Apoptosis of cells in ascitic fluid was detected by flow cytometry. The expression of Ki67 and CD34 was detected by immunohistochemical staining. Administration of liposome-plasmid complexes encoding mutant survivin-T34A inhibited tumor growth, reduced the number of tumor nodules and the volume of ascitic fluid, and decreased abdomen circumference and tumor weight. The number of Ki67-positive cells was markedly reduced in the DOTAP+PST34A group compared with the remaining groups. Flow cytometry demonstrated that the number of cells in the sub-G1 phase (apoptosis) increased in the DOTAP+PST34A group compared with all other groups. In addition, tumors in the DOTAP+PST34A group exhibited lower microvessel density compared with all other groups. In the present study, liposome-plasmid DNA encoding mutant survivin-T34A could inhibit tumor growth of cervical cancer. This inhibition may be associated with an increase in the apoptosis rate of tumor cells and a reduction in angiogenesis.

Naringin inhibits ovarian tumor growth by promoting apoptosis: An in vivo study

The aim of the present study was to investigate the antitumor activities of naringin in ovarian cancer, and to assess the underlying mechanisms. Ovarian tumor cells were implanted into nude mice to produce ovarian tumors in vivo. The mice were divided into six groups: Control, low dose naringin [0.5 mg/kg, intraperitoneal (i.p.)], middle dose naringin (1 mg/kg, i.p.), high dose naringin (2 mg/kg, i.p.), positive control (cisplatin, 2 mg/kg, i.p.) and a combination of cisplatin and naringin (both 2 mg/kg). Following administration of naringin and/or cisplatin, the tumor size and weight were measured. Apoptosis of tumor cells was detected using a terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Apoptosis-associated gene expression was detected using reverse transcription-polymerase chain reaction and immunohistochemistry. In the range of 0.5–2 mg/kg, naringin dose-dependently inhibited tumor growth, as demonstrated by a decrease in tumor size and weight. Naringin promoted apoptosis of the ovarian tumor cells. Additionally, naringin reduced the expression of B-cell lymphoma (Bcl)-2, Bcl-extra large (Bcl-xL), cyclin D1, c-Myc and survivin, while it increased the expression of caspase-3 and caspase-7. The data demonstrated that naringin inhibited ovarian tumor growth in vivo. Its mechanisms may be associated with caspase-7-, caspase-3-, Bcl-2- and Bcl-xL-mediated apoptosis. Nevertheless, the clinical application of naringin in the treatment of ovarian cancer requires further study.

Natural Borneol Enhances Paclitaxel-Induced Apoptosis of ESCC Cells by Inactivation of the PI3K/AKT

Paclitaxel (PTX) has been used in a variety of malignancies for inhibiting tumor development and improving survival. However, its clinical application is limited due to poor solubility, drug resistance, and gastrointestinal reactions. Natural borneol (NB), as a promoter, could help to improve drug absorption. Therefore, the aims of the present study were to investigate the ability of NB to synergize with PTX to induce human esophageal squamous cell carcinoma (ESCC) cells apoptosis and the underlying mechanism of synergistic effects. In this study, our findings showed that NB could effectively synergize with PTX to inhibit the survival of ESCC cells by inducing apoptosis. The molecular mechanism by western blotting elucidated that combination treatment with PTX and NB significantly activated apoptotic pathway by triggering upregulation of cleaved caspase-3 expression and downregulation of survivin and P-AKT expression. These results demonstrated that NB could strongly potentiate PTX-induced apoptosis in ESCC cells through suppressing PI3K/AKT pathway. Thus, the combination therapy with NB and PTX might be a promising treatment strategy for human esophageal cancer.

PRACTICAL APPLICATION

Esophageal cancer is one of the most common cancers in the world. It has brought about a major public health problem. Many natural agents have been employed in the synergized treatments of esophageal cancer. This study provides a comprehensive way to investigate the ability of borneol to synergize with paclitaxel to induce human esophageal squamous cell carcinoma cells apoptosis and the underlying mechanism of synergistic effects. The research showed that the combination treatment with some natural agents might be a promising treatment strategy for human esophageal cancer.

LncRNA LINC00880 promotes cell proliferation, migration, and invasion while inhibiting apoptosis by targeting CACNG5 through the MAPK signaling pathway in spinal cord ependymoma

The present study was to investigate the effect of lncRNA LINC00880 targeting CACNG5 on cell proliferation, migration, invasion, and apoptosis in spinal cord ependymoma (SCE) through the MAPK signaling pathway. GEO database was used to download gene expression data related with SCE (GSE50161 and GSE66354) and annotation file. LncRNA with differential expression was predicted by Multi Experiment Matrix website (MEM). The target gene was analyzed by KEGG pathway enrichment analysis. SCE tissues and adjacent tissues were collected. The positive expression of CACNG5 protein was tested by immunohistochemistry. Expression of LINC00880, CACNG5, and MAPK signaling pathway-related proteins was measured with qRT-PCR and Western blotting. Cell proliferation, migration, invasion, cycle, and apoptosis were detected using MTT, Transwell assay, Scratch test, and Flow cytometry. SCE tissues showed increased LINC00880 expression. CACNG5 was a target gene of LINC00880 and correlated with MAPK signaling pathway. Compared with adjacent tissues, SCE tissues showed lower positive expression of CACNG5. Compared with the blank group, LINC00880 expression was higher in the LINC00880 vector and LINC00880 vector + CACNG5 vector groups, and lower in the si-LINC00880 and si-LINC00880 + si-CACNG5 groups; in the LINC00880 vector and si-CACNG5 groups, expression of survivin, p38MAPK, ERK1/2, JNK1/2/3 increased and CACNG5 and Bax expression reduced, the proliferation, invasion and migration of tumor cells increased, and apoptosis rate decreased. Opposite results were found in the si-LINC00880 and CACNG5 vector groups. The findings indicate that lncRNA LINC00880 targeting CACNG5 inhibits cell apoptosis and promotes proliferation, migration, and invasion in SCE through the MAPK signaling pathway.

Survivin-Based Treatment Strategies for Squamous Cell Carcinoma

Survivin, an anti-apoptotic molecule abundantly expressed in most human neoplasms, has been reported to contribute to cancer initiation and drug resistance in a wide variety of human tumors. Efficient downregulation of survivin can sensitize tumor cells to various therapeutic interventions, generating considerable efforts in its validation as a new target in cancer therapy. This review thoroughly analyzes up-to-date information on the potential of survivin as a therapeutic target for new anticancer treatments. The literature dealing with the therapeutic targeting of survivin will be reviewed, discussing specifically squamous cell carcinomas (SCCs), and with emphasis on the last clinical trials. This review gives insight into the recent developments undertaken in validating various treatment strategies that target survivin in SCCs and analyze the translational possibility, identifying those strategies that seem to be the closest to being incorporated into clinical practice. The most recent developments, such as dominant-negative survivin mutants, RNA interference, anti-sense oligonucleotides, small-molecule inhibitors, and peptide-based immunotherapy, seem to be helpful for effectively downregulating survivin expression and reducing tumor growth potential, increasing the apoptotic rate, and sensitizing tumor cells to chemo- and radiotherapy. However, selective and efficient targeting of survivin in clinical trials still poses a major challenge.

Tumor expression of survivin, p53, cyclin D1, osteopontin and fibronectin in predicting the response to neo-adjuvant chemotherapy in children with advanced malignant peripheral nerve sheath tumor

PURPOSE

Selected cell-cycle regulators and extracellular matrix proteins were found to play roles in malignant peripheral nerve sheath tumor (MPNST) biology. We aimed to analyze whether initial tumor tissue expressions of survivin, p53, cyclin D1, osteopontin (OPN) and fibronectin (FN) correlate with the response to neo-adjuvant CHT (naCHT) in children with advanced inoperable MPNST.

METHODS

The study included 26 children with MPNST (M/F 14/12, median age 130 months) treated in Polish centers of pediatric oncology between 1992 and 2013. Tissue expression of markers was studied immunohistochemically in the manually performed tissue microarrays and assessed semi-quantitatively as low and high, based on the rate of positive cells and staining intensity.

RESULTS

Good response to naCHT was noted in 47.6%, while poor-in 52.4% of patients. The response to naCHT was influenced negatively by the presence of neurofibromatosis NF1 and high initial tumor tissue expression of OPN, survivin, p53 and cyclin D1. Patients with high tumor expression of either OPN, survivin or p53 and those with simultaneous high expression of ≥ 3 of the markers, responded significantly worse to naCHT, than patients, in whom expression of ≤ 2 markers were detected at diagnosis. Nearly, 85% of patients expressing ≥ 3 markers, responded poor to CHT; while 87.5% of children, expressing ≤ 2 markers, were good responders.

CONCLUSION

The initial tumor tissue expression of OPN, survivin, p53 and cyclin D1 may serve as markers to predict response to naCHT in pediatric advanced MPNST. Future studies in more numerous group of patients are needed to confirm these preliminary results.

Tumour-specific triple-regulated oncolytic herpes virus to target glioma

Oncolytic herpes simplex virus type 1 (oHSV-1) therapy is an emerging treatment modality that selectively destroys cancer. Here we report use of a glioma specific HSV-1 amplicon virus (SU4-124 HSV-1) to selectively target tumour cells. To achieve transcriptional regulation of the SU4-124 HSV-1 virus, the promoter for the essential HSV-1 gene ICP4 was replaced with a tumour specific survivin promoter. Translational regulation was achieved by incorporating 5 copies of microRNA 124 target sequences into the 3'UTR of the ICP4 gene. Additionally, a 5'UTR of rat fibroblast growth factor -2 was added in front of the viral ICP4 gene open reading frame. Our results confirmed enhanced expression of survivin and eIF4E in different glioma cells and increased micro-RNA124 expression in normal human and mouse brain tissue. SU4-124 HSV-1 had an increased ICP4 expression and virus replication in different glioma cells compared to normal neuronal cells. SU4-124 HSV-1 exerted a strong antitumour effect against a panel of glioma cell lines. Intracranial injection of SU4-124 HSV-1 did not reveal any sign of toxicity on day 15 after the injection. Moreover, a significantly enhanced antitumour effect with the intratumourally injected SU4-124 HSV-1 virus was demonstrated in mice bearing human glioma U87 tumours, whereas viral DNA was almost undetectable in normal organs. Our study indicates that incorporation of multiple cancer-specific regulators in an HSV-1 system significantly enhances both cancer specificity and oncolytic activity.

Asplatin enhances drug efficacy by altering the cellular response

Aspirin, a widely used anti-inflammatory drug, has been shown to be effective for the prevention and remission of cancers (Science, 2012, 337(21) 1471-1473). Asplatin, a Pt(iv) prodrug of cisplatin with the ligation of aspirin (c,c,t-[PtCl2(NH3)2(OH)(aspirin)]), demonstrates significantly higher cytotoxicity than cisplatin towards tumor cells and almost fully overcomes the drug resistance of cisplatin resistant cells. In this work, we have studied the molecular mechanism of asplatin by investigating the cellular response to this compound in order to understand the prominent inhibitory effect on the proliferation of cancer cells. The apoptosis analyses and the related gene expression measurements show that aspirin released from asplatin significantly modulates the cellular response to the platinum agent. Asplatin promotes the apoptosis via the BCL-2 associated mitochondrial pathway. The down-regulation of BCL-2 along with the up-regulation of BAX and BAK enhances the mitochondrial outer membrane permeability, resulting in the cytochrome c release from mitochondria into the cytosol. This event promotes the apoptosis by activation of caspase processing. Consequently, the ligation of aspirin significantly enhances the drug efficacy of the platinum complex in the low micromolar range. The alteration of the cellular response is probably responsible for the circumvention of the cisplatin resistance by asplatin. These results provide an insight into the mechanism of asplatin and provide information for designing new classic platinum drugs.

Omega-3 Fatty Acid Grafted PAMAM-Paclitaxel Conjugate Exhibits Enhanced Anticancer Activity in Upper Gastrointestinal Cancer Cells

Upper Gastrointestinal Cancers (UGCs) are a leading cause of cancer-related deaths worldwide. Paclitaxel (PTX) is frequently used for the treatment of UGCs; however, low bioavailability, reduced solubility, and dose-dependent toxicity impede its therapeutic use. PAMAMG_4.0 -NH₂ -DHA is synthesized by linking amine-terminated fourth-generation poly(amidoamine) (PAMAMG_4.0 -NH₂ ) dendrimers with omega-3 fatty acid docosahexaenoic acid (DHA). Next, PAMAMG_4.0 -NH₂ -DHA-PTX (DHATX) and PAMAMG_4.0 -NH₂ -PTX (PAX) conjugates are synthesized by subsequent covalent binding of PTX with PAMAMG_4.0 -NH₂ -DHA and PAMAMG_4.0 -NH₂ , respectively. ¹ H-NMR and MALDI-TOF analyses are performed to confirm conjugation of DHA to PAMAMG_4.0 -NH₂ and PTX to PAMAMG_4.0 -NH₂ -DHA. The cell viability, clonogenic cell survival, and flow cytometry analyses are used to determine the anticancer activity of PTX, PAX, and DHATX in UGC cell lines. The in vitro data indicate that treatment with DHATX is significantly more potent than PTX or PAX at inhibiting cellular proliferation, suppressing long-term survival, and inducing cell death in UGC cells.

Survivin, a molecular target for therapeutic interventions in squamous cell carcinoma

Squamous cell carcinoma (SCC) is the most common cancer worldwide. The treatment of locally advanced disease generally requires various combinations of radiotherapy, surgery, and systemic therapy. Despite aggressive multimodal treatment, most of the patients relapse. Identification of molecules that sustain cancer cell growth and survival has made molecular targeting a feasible therapeutic strategy. Survivin is a member of the Inhibitor of Apoptosis Protein (IAP) family, which is overexpressed in most of the malignancies including SCC and totally absent in most of the normal tissues. This feature makes survivin an ideal target for cancer therapy. It orchestrates several important mechanisms to support cancer cell survival including inhibition of apoptosis and regulation of cell division. Overexpression of survivin in tumors is also associated with poor prognosis, aggressive tumor behavior, resistance to therapy, and high tumor recurrence. Various strategies have been developed to target survivin expression in cancer cells, and their effects on apoptosis induction and tumor growth attenuation have been demonstrated. In this review, we discuss recent advances in therapeutic potential of survivin in cancer treatment.

Esophageal cancer's 100 most influential manuscripts: a bibliometric analysis

Bibliometric analysis highlights key topics and publications that have shaped the understanding and management of esophageal cancer (EC). Here, the 100 most cited manuscripts in the field of EC are analyzed. The Thomson Reuters Web of Science database with the search terms 'esophageal cancer' or 'esophageal carcinoma' or 'oesophageal cancer' or 'oesophageal carcinoma' or 'gastroscopy' was used to identify all English language full manuscripts for the study. The 100 most cited papers were further analyzed by topic, journal, author, year, and institution. A total of 121,556 eligible papers were returned and the median (range) citation number was 406.5 (1833 to 293). The most cited paper focused on the role of perioperative chemotherpy in EC (1833 citations). Gastroenterology published the highest number of papers (n = 15, 6362 citations) and The New England Journal of Medicine received the most citations (n = 12, 12125 citations). The country and year with the greatest number of publications were the USA (n = 50), and 1998, 1999, and 2000 (n = 7). The most ubiquitous topic was the pathology of EC (n = 66) followed by management of EC (n = 54), and studies related to EC prognosis (n = 44). The most cited manuscripts highlighted the pathology, management, and prognosis of EC and this bibliometirc review provides the most influential references serving as a guide to popular research themes.

Special AT-rich sequence binding protein 1 promotes tumor growth and metastasis of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma is one of the most aggressive malignancies worldwide. Special AT-rich sequence binding protein 1 is a nuclear matrix attachment region binding protein which participates in higher order chromatin organization and tissue-specific gene expression. However, the role of special AT-rich sequence binding protein 1 in esophageal squamous cell carcinoma remains unknown. In this study, western blot and quantitative real-time polymerase chain reaction analysis were performed to identify differentially expressed special AT-rich sequence binding protein 1 in a series of esophageal squamous cell carcinoma tissue samples. The effects of special AT-rich sequence binding protein 1 silencing by two short-hairpin RNAs on cell proliferation, migration, and invasion were assessed by the CCK-8 assay and transwell assays in esophageal squamous cell carcinoma in vitro. Special AT-rich sequence binding protein 1 was significantly upregulated in esophageal squamous cell carcinoma tissue samples and cell lines. Silencing of special AT-rich sequence binding protein 1 inhibited the proliferation of KYSE450 and EC9706 cells which have a relatively high level of special AT-rich sequence binding protein 1, and the ability of migration and invasion of KYSE450 and EC9706 cells was distinctly suppressed. Special AT-rich sequence binding protein 1 could be a potential target for the treatment of esophageal squamous cell carcinoma and inhibition of special AT-rich sequence binding protein 1 may provide a new strategy for the prevention of esophageal squamous cell carcinoma invasion and metastasis.

Autocrine and Paracrine Mechanisms Promoting Chemoresistance in Cholangiocarcinoma

Resistance to conventional chemotherapeutic agents, a typical feature of cholangiocarcinoma, prevents the efficacy of the therapeutic arsenal usually used to combat malignancy in humans. Mechanisms of chemoresistance by neoplastic cholangiocytes include evasion of drug-induced apoptosis mediated by autocrine and paracrine cues released in the tumor microenvironment. Here, recent evidence regarding molecular mechanisms of chemoresistance is reviewed, as well as associations between well-developed chemoresistance and activation of the cancer stem cell compartment. It is concluded that improved understanding of the complex interplay between apoptosis signaling and the promotion of cell survival represent potentially productive areas for active investigation, with the ultimate aim of encouraging future studies to unveil new, effective strategies able to overcome current limitations on treatment.

Decreased expression of CDH1 or CTNNB1 affects poor prognosis of patients with esophageal cancer

Background

E-cadherin/CDH1 is one of the proteins involved in cell adhesion, and it is known that decreased expression of E-cadherin induces lymph node metastasis in esophageal cancer. Beta catenin/CTNNB1, which is an important component of the Wnt signaling pathway, binds to E-cadherin at the cell membrane, where the complex of these two proteins functions in the stabilization of cell adhesion. However, its role in the pathogenesis of esophageal cancer is still unknown.

Methods

This study included 86 patients with esophageal cancer who underwent surgery between 1998 and 2007. The expression of the E-cadherin/CDH1 gene product (E-cadherin/CDH1) and that of the beta catenin/CTNNB1 protein in the cell membrane were analyzed by immunohistochemistry. We examined the correlations among CDH1 or CTNNB1 expression, clinicopathological factors, and the prognosis of patients with ESCC.

Results

CDH1 and CTNNB1 were expressed in 52.3 % (45/86) and 36.0 % (31/86) of tumor samples, respectively. Both CDH1 and CTNNB1 were co-expressed in 22.1 % (19/86) of esophageal cancer tissues. CDH1 expression correlated with the p-stage (stages I–II vs stages III–IV, p = 0.032), T factor (T1–2 vs T3–4, p = 0.0088), and lymphatic invasion (p = 0.019). However, CDH1 expression did not correlate with the N factor or the blood vessel invasion. CTNNB1 expression correlated with the T factor (T1–2 vs T3–4, p = 0.0015), p-stage (stages I–II vs stages III–IV, p = 0.030), and lymphatic invasion (p = 0.007). The CDH1(+)/CTNNB1(+) phenotype was inversely correlated with the T factor, N factor, p-stage, lymphatic invasion, and blood vessel invasion. Furthermore, patients whose tumors were double-positive for CDH1 and CTNNB1 had a significantly higher survival rate than those whose tumors were negative for CDH1 or CTNNB1 (log-rank test, p = 0.0192). The T factor and N factor had a strong negative correlation with double-positive tumors. These were both independent prognostic factors, as was the double-positive phenotype. A univariate analysis indicated that the T factor, the N factor, and CDH1 and CTNNB1 co-expression were significant variables that predicted survival (hazard ratio, 2.387; 95 % confidence interval, 1.115–5.102; p = 0.025).

Conclusions

Decreased expression of CDH1 or CTNNB1 in the cell membranes of cancer cells is associated with poor survival of patients with esophageal cancer.

Pro-apoptotic effects of rHSG on C6 glioma cells

Our previous in vitro study demonstrated that the rat hyperplasia suppressor gene (rHSG) inhibited the proliferation of C6 cells. In the present study, we investigated further the effects of rHSG overexpression on the apoptosis of C6 cells and the possible pathways involved. Hoechst 33342/PI double staining and comet assay were used to examine the morphological characteristics of apoptosis and to examine the effects of rHSG on the apoptosis of the C6 cells. Western blot analysis was used to determine the effects of rHSG overexpression on the protein expression levels of poly(ADP-ribose) polymerase (PARP), cleaved caspase-3, phosphorylated extracellular signal-regulated kinase 1/2 (p-Erk1/2), phosphorylated Akt (p-Akt) and phosphoinositide 3-kinase (PI3K)/Akt, as well as on the mitogen-activated protein kinase (MAPK) pathways induced by insulin-like growth factor (IGF)-1. Our results revealed that the C6 cells transfected with the rHSG adenoviral vector (Adv-rHSG-GFP group) efficiently expressed rHSG protein; Hoechst 33342/PI double staining and comet assay revealed that rHSG increased C6 cell apoptosis and induced DNA damage. Western blot analysis indicated that rHSG overexpression significantly increased the level of full-length PARP at 24 and 72 h (P<0.01), but decreased the level at 48 h following transfection (P<0.01), while the proteins levels of cleaved PARP and cleaved caspase-3 increased significantly (P<0.01). The protein expression of p-Erk1/2 and p-Akt began to decrease at 48 h post-transfection (P<0.01). In addition, the protein levels of Akt and Erk1/2 induced by IGF-1 were significantly inhibited. On the whole, the findings of the present study demonstrate that rHSG overexpression induces the apoptosis of rat glioma cells, and that these effects may involve the PI3K/Akt and MAPK pathways.

Nuclear expression of TCF4/TCF7L2 is correlated with poor prognosis in patients with esophageal squamous cell carcinoma

The prognosis for patients with esophageal cancer remains poor. Therefore, the identification of novel target molecules for the treatment of esophageal cancer is necessary. Here, we investigated the clinicopathological significance of transcription factor 4/transcription factor 7-like 2 (TCF4/TCF7L2) in resectable esophageal squamous cell carcinoma (ESCC), because TCF4/TCF7L2 expression has not been studied in esophageal cancer previously.

This study included 79 patients with esophageal cancer who underwent surgery between 1998 and 2005. The expression of the TCF4/TCF7L2 protein in the nucleus of esophageal cancer cells was analyzed using immunohistochemistry. We examined the correlation between TCF4/TCF7L2 expression, clinicopathological factors, and prognosis in patients with ESCC.

TCF4/TCF7L2 was expressed in 57 % (45/79) of patients. TCF4/TCF7L2 expression was correlated with T factor (T1 vs. T2-4, p = 0.001), stage (I vs. II-IV, p =0.0058), Ly factor (p =0.038), and V factor (p =0.038) and did not correlate with age, gender or N factor. Furthermore, patients who were positive for TCF4/TCF7L2 had a significantly lower survival rate than those who were negative for TCF4/TCF7L2 (log-rank test, p = 0.0040). TCF4/TCF7L2 expression significantly affected the survival of patients with ESCC. Positive expression of TCF4/TCF7L2 was correlated with a poor prognosis after a curative operation in patients with ESCC.

Traditional Chinese medicine targeting apoptotic mechanisms for esophageal cancer therapy

Esophageal cancer is one of the most common types of cancer in the world, and it demonstrates a distinct geographical distribution pattern in China. In the last decade, inducing apoptosis with traditional Chinese medicine (TCM) has become an active area in both fundamental and clinical research on cancer therapy. In this review, we summarize the molecular mechanisms by which TCM induces apoptosis in esophageal cancer cells. These mechanisms are generally related but not limited to targeting the extrinsic death receptor pathway, the intrinsic mitochondrial pathway, and the endoplasmic reticulum (ER) stress pathway. By using different monomers and composite prescriptions of TCM, it is possible to modulate the ratio of Bcl-2/Bax, regulate the expression of caspase proteases and mitochondrial transmembrane potential, increase the expression of Fas and p53, down-regulate NF-κB pathway and the expression of Chop and survivin, and block cell cycle progression.

Targeting survivin using a combination of miR‑494 and survivin shRNA has synergistic effects on the suppression of prostate cancer growth

Castration-resistant prostate cancer (CRPC) remains an obstacle in the current treatment provided for prostate cancer (PCa). Survivin, an apoptosis inhibitor, has been found to be involved in the progression of PCa, and is a promising candidate target for CRPC therapy. Micro (mi)RNAs are involved in the progression of PCa through the regulation of multiple genes. One of the objectives of the present study was to investigate the effect of miRNA (miR)‑494 on the expression of survivin, as well as on PCa growth. The present study also aimed to assess whether co-transfecting miR‑494 with survivin short hairpin (sh)RNA has synergistic effects on suppressing PCa proliferation or the expression of survivin. Gene Expression Omnibus datasets with clinical PCa miRNA expression profiles were utilized to analysis the expression of miR‑494 in Ca, compared with normal prostate samples. PC3 cells, a CRPC cell line, were transfected with either an miR‑494 expression adenovirus, a survivin shRNA adenovirus or the two together, to examine their effect on PCa growth and the expression of survivin in vitro and in vivo. miR‑494 was downregulated in PCa tissue samples and in the PC‑3 cell line. miR‑494 targeted survivin at the translational level in PCa. Overexpression of miR‑494 and silencing survivin RNA through the use of survivin shRNA inhibited the expression of survivin and attenuated PC‑3 cell growth in vitro and in vivo. Notably, co‑transfecting miR‑494 with survivin shRNA had synergistic effects on suppressing prostate cancer proliferation via further suppression of the expression of survivin. These results suggested that using multiple methods to inhibit the function of survivin may have improved efficacy for treating PCa.

Survivin activates NF‑κB p65 via the IKKβ promoter in esophageal squamous cell carcinoma

Survivin and transcription factor p65 (NF‑κB p65) participate in the progression of esophageal squamous cell carcinoma (ESCC). However, the mechanism of NF‑κB p65 activation in ESCC remains to be elucidated. The aim of the present study was to investigate the role of survivin in the activation of NF‑κB p65 in ESCC. The expression levels of survivin, NF‑κB p65, inhibitor of nuclear factor κB kinase subunit α (IKKα) and inhibitor of nuclear factor κB kinase subunit β (IKKβ) were detected in ESCC tissue samples. Eca109 and KYSE150 cells were cultured and survivin activity was modulated via transfection with an overexpression plasmid, a small hairpin RNA plasmid and a specific inhibitor. Quantitative reverse transcription-polymerase chain reaction and western blotting assays were conducted to assess the effects of survivin on the expression levels of IKKα, IKKβ and NF‑κB p65. Cell cycle and apoptosis assays were conducted to detect surviving-dependent cellular behavior changes. In addition, the luciferase reporter gene assay and chromatin immunoprecipitation assay were conducted to determine the genomic sites responsible for surviving-induced activation of NF‑κB p65. The present study demonstrated that the expression of survivin is positively correlated with IKKα and IKKβ in ESCC tissues. Survivin affected the mRNA and protein expression levels of IKKα, IKKβ, and NF‑κB p65 in Eca109 and KYSE150 cells. Furthermore, survivin increased the transcriptional activity of the IKKβ promoter and bound to the IKKβ promoter region in the Eca109 cells. Downregulation of survivin arrested the cell cycle at the G2/M phase and induced apoptosis. Results of the present study suggest that survivin activates NF‑κB p65 in Eca109 cells via binding to the IKKβ promoter region and upregulating IKKβ promoter transcriptional activity. Survivin overexpression activates NF‑κB p65, which is important in the acquisition and maintenance of the oncogenic characteristics of ESCC.

GADD45A expression is correlated with patient prognosis in esophageal cancer

The prognosis of patients with esophageal cancer remains poor, and the tumor-node-metastasis classification system is not sufficient for predicting patient prognoses. Therefore, the identification of novel predictive markers for esophageal cancer is required. The present study investigated the clinicopathological significance of growth arrest and DNA damage-inducible 45α (GADD45A) and p53 in resectable esophageal squamous cell carcinoma (ESCC). The study consisted of 62 patients with esophageal cancer who underwent surgery between 2001 and 2007. The expression of the GADD45A gene product (GADD45A) and the p53 protein was analyzed by immunohistochemistry. The correlations among GADD45A expression, clinicopathological factors and prognosis were then analyzed in the patients with ESCC. GADD45A and p53 were expressed in 56.5% (35/62) and 48.4% (30/62) of patients, respectively. The expression of GADD45A did not show a marked correlation with that of p53. However, GADD45A expression correlated with pathological stage (stage 0-I vs. stages II-IV; P=0.014) and did not correlate with the tumor (T) or node (N) status. Furthermore, patients who were positive for GADD45A exhibited a significantly higher survival rate than those who were negative for GADD45A (log-rank test, P=0.009). Multivariate analysis indicated that T status, N status and GADD45A expression were significant variables predicting survival (hazard ratio, 2.486; 95% confidence interval, 1.168-5.290; P=0.018). Overall, GADD45A expression significantly affected the survival of patients with ESCC, and the reduced expression of GADD45A was correlated with a poor prognosis following curative surgery in these patients.

Overexpression of miR-214-3p in esophageal squamous cancer cells enhances sensitivity to cisplatin by targeting survivin directly and indirectly through CUG-BP1

Based on its marked overexpression in multiple malignancies and its roles in promoting cell survival and proliferation, survivin is an attractive candidate for targeted therapy. Towards this end, a detailed understanding of the mechanisms regulating survivin expression in different cancer cells will be critical. We have previously shown that the RNA-binding protein (RBP) CUG-BP1 is overexpressed in esophageal cancer cells and post-transcriptionally regulates survivin in these cells. The objective of this study was to investigate the role of microRNAs (miRs) in regulating survivin expression in esophageal cancer cells. Using miR expression profiling analysis, we found that miR-214-3p is one of the most markedly downregulated miRs in two esophageal squamous cancer cell lines compared to esophageal epithelial cells. Interestingly, using miR target prediction programs, both survivin and CUG-BP1 mRNA were found to contain potential binding sites for miR-214-3p. Forced expression of miR-214-3p in esophageal cancer cells leads to a decrease in the mRNA and protein levels of both survivin and CUG-BP1. This effect is due to decreased mRNA stability of both targets. By contrast, silencing miR-214-3p in esophageal epithelial cells leads to an increase in both survivin and CUG-BP1 mRNA and protein. To determine whether the observed effect of miR-214-3p on survivin expression was direct, mediated through CUG-BP1, or both, binding studies utilizing biotin pull-down assays and heterologous luciferase reporter constructs were performed. These demonstrated that the mRNA of survivin and CUG-BP1 each contain two functional miR-214-3p binding sites as confirmed by mutational analysis. Finally, forced expression of miR-214-3p enhances the sensitivity of esophageal cancer cells to Cisplatin-induced apoptosis. This effect is abrogated with rescue expression of survivin or CUG-BP1. These findings suggest that miR-214-3p acts as a tumor suppressor and that its downregulation contributes to chemoresistance in esophageal cancer cells by targeting both survivin and CUG-BP1.

Use of a Novel Integrase-Deficient Lentivirus for Targeted Anti-Cancer Therapy With Survivin Promoter-Driven Diphtheria Toxin A

As an immunotoxin, diphtheria toxin has been widely used in gene therapy and gene function assays for its roles in protein synthesis inhibition, and the aim of our study is to set up a nonintegrating lentiviral system for specific expression of diphtheria toxin A (DTA) used in cancer gene therapy.Here, we established a lentiviral system that could coordinately express fluorescent protein and DTA driven by the cytomegalovirus (CMV) promoter, which is convenient for us to precisely trace the expression of DTA and monitor the process of lentivirus packaging. To achieve safer cancer therapy, we replaced the CMV promoter with the Survivin promoter, a specific promoter that is dramatically activated in cancer tissues and cells, but not in normal tissues and cells, and that will impose greater therapeutic potential because a significant expression difference occurred between these 2 groups. Meanwhile, we obtained integrase-deficient lentivirus (IDLV) after packaging with the integrase mutant, which expresses defective integrase RRK262263264AAH, to minimize the side effects that derived from the insertional mutagenesis of the host genome.Our results suggest that the IDLV system that we generated possesses therapeutic potential in cancers in vitro and in vivo.

Lentiviral vector-mediated survivin shRNA delivery in gastric cancer cell lines significantly inhibits cell proliferation and tumor growth

It has been well documented that survivin has multiple functions including cytoprotection, inhibition of cell death, and cell cycle regulation, particularly at the mitotic stage of the cell cycle, all of which favor cancer survival. Its expression in normal tissue is developmentally regulated, and any type of deregulation in survivin expression favors cancer survival. Gastric cancer is one of the most common malignancies and the second most common cause of cancer-related mortality worldwide. The molecular mechanisms involved in the transformation and progression of gastric cancer remain unclear. In the present study, we investigated the effect of lentiviral vector-mediated survivin shRNA delivery in gastric cancer cell lines. Lentiviral-mediated survivin shRNA was used to knock down survivin expression in gastric cancer cell lines SGC-7901, MGC-803 and MKN-28. The Τranswell chemotaxis and the CCK-8 assays were used to assess the migration and proliferation of the tumor cells, respectively. TUNEL assay was used to detect apoptosis. Quantitative real-time PCR and western blot analysis were used to quantify mRNA and protein levels, respectively. Our results demonstrated that lentiviral-mediated RNAi markedly suppressed the survivin expression in all three gastric cancer cell lines. Significant decrease in survivin mRNA and protein expression were detected in the gastric cancer cell lines stably transfected with the lentiviral survivin shRNA vector, and knockdown of survivin also significantly inhibited the proliferation and migration in the gastric cancer cells and tumorigenicity in a xenograft animal model. Our results indicated that aberrant high cytoplasmic survivin expression in gastric cancer cells is associated with increased proliferation index and tumor growth. In conclusion, our results suggest that lentiviral-mediated gene therapy has the potential to be developed into a novel therapeutic strategy for the treatment of gastric cancer.

Survivin expression and serum levels in pancreatic cancer

BACKGROUND

Survivin, an inhibitor of apoptosis, is overexpressed in pancreatic ductal adenocarcinoma (PDAC). Its expression is known to be associated with poor clinical outcome. However, to our knowledge, there has been no study to characterize its usefulness as a serum marker for human pancreatic cancer. Furthermore, the relation between survivin expression and the serum level of survivin has not been widely studied in PDAC. We performed this study to investigate the expression and serum level of survivin in PDAC and its clinical significance as a prognostic factor.

METHODS

We performed immunohistochemical staining for survivin in formalin-fixed, paraffin-embedded blocks from 80 PDAC tissues. The serum level of survivin from the patients (n = 80) and age-matched healthy volunteers (n = 80) were analyzed by enzyme-linked immunosorbent assays (ELISAs) prior to surgical resection. Levels of expression were correlated with clinicopathological parameters.

RESULTS

Serum survivin concentrations were significantly elevated in patients with PDAC when compared with healthy sera (P < 0.001). High serum survivin levels were significantly associated with perineural invasion, venous invasion, lymph node status (N stage), cell differentiation, and recurrence but not with the tumor size, age, gender of the patients, or tumor location. The median overall survival time of the group with normal serum survivin levels was longer than that of the group with elevated serum survivin. The independent factors associated with overall survival were advanced pancreatic cancer and elevated serum survivin level. Of the 80 cases of PDAC, 65 (81.25 %) were positive for survivin expression. There were significant associations between survivin expression and perineural invasion, venous invasion, and lymph node status. A significant difference in overall survival was associated with survivin expression.

CONCLUSIONS

Patients with elevated serum survivin level and high survivin expression at diagnosis demonstrated a poor outcome. Detection of serum survivin or tissue survivin expression may predict the prognosis of patients with PDAC.

Slug-dependent upregulation of L1CAM is responsible for the increased invasion potential of pancreatic cancer cells following long-term 5-FU treatment

Background

Pancreatic adenocarcinoma is a lethal disease with 5-year survival of less than 5%. 5-fluorouracil (5-FU) is a principal first-line therapy, but treatment only extends survival modestly and is seldom curative. Drug resistance and disease recurrence is typical and there is a pressing need to overcome this. To investigate acquired 5-FU resistance in pancreatic adenocarcinoma, we established chemoresistant monoclonal cell lines from the Panc 03.27 cell line by long-term exposure to increasing doses of 5-FU.

Results

5-FU-resistant cell lines exhibited increased expression of markers associated with multidrug resistance explaining their reduced sensitivity to 5-FU. In addition, 5-FU-resistant cell lines showed alterations typical for an epithelial-to-mesenchymal transition (EMT), including upregulation of mesenchymal markers and increased invasiveness. Microarray analysis revealed the L1CAM pathway as one of the most upregulated pathways in the chemoresistant clones, and a significant upregulation of L1CAM was seen on the RNA and protein level. In pancreatic cancer, expression of L1CAM is associated with a chemoresistant and migratory phenotype. Using esiRNA targeting L1CAM, or by blocking the extracellular part of L1CAM with antibodies, we show that the increased invasiveness observed in the chemoresistant cells functionally depends on L1CAM. Using esiRNA targeting β-catenin and/or Slug, we demonstrate that in the chemoresistant cell lines, L1CAM expression depends on Slug rather than β-catenin.

Conclusion

Our findings establish Slug-induced L1CAM expression as a mediator of a chemoresistant and migratory phenotype in pancreatic adenocarcinoma cells.

Androgen receptor promotes esophageal cancer cell migration and proliferation via matrix metalloproteinase 2

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies worldwide. Androgen receptor (AR) plays an important role in many kinds of cancers. However, the molecular mechanisms of AR in ESCC are poorly characterized. In the present study, Western blot analysis and real-time quantitative PCR were performed to identify differentially expressed AR in 40 ESCC tissue samples, which revealed that the messenger RNA (mRNA) and protein expression of AR is upregulated in the ESCC tissue samples. AR overexpression induced increases in ESCC cell invasion and proliferation in vitro. Silencing of AR inhibited the proliferation of KYSE450 cells which have a relatively high level of AR, and the invasion of KYSE450 cells was distinctly suppressed. Furthermore, AR knockdown led to substantial reductions in matrix metalloproteinase 2 (MMP2) and p-AKT levels in ESCC cell lines, but no significant change in AKT and MMP9 expression. These results suggest that AR is involved in tumor progression, and thus, AR could represent selective targets for the molecularly targeted treatments of ESCC.

Serum survivin increases in prolactinoma

Background

Prolactinoma is the most common adult pituitary adenoma. Survivin is a member of the family of inhibitors of apoptosis proteins. Its expression is observed in many tumors. Survivin expression has shown in prolactinoma tissue before but no study exists showing serum survivin level. The aim of the present study was to investigate serum survivin levels in patients with prolactinoma and demonstrate its value in diagnosis of the disease.

Methods

The group of patients consisted of 25 women, aged from 17 to 51 years. As a control group, 21 healthy women, aged from 22 to 45 years were included. Twenty patients had microprolactinoma, while five patients had macroprolactinoma. All patients had received dopamine agonist treatment. Serum survivin levels were measured in all of the groups.

Results

Survivin levels were significantly higher in prolactinoma patients compared to controls (19.04 (10 - 38) pg/mL; 15.05 (8 - 22) pg/mL; P = 0.042). There was no difference between microadenoma and macroadenoma patients in survivin levels (19.22 (10 - 38) pg/mL; 18.40 (16 - 22) pg/mL; P = 0.914). In correlation analysis, survivin was not correlated with other parameters.

Conclusions

We consider that higher survivin levels might be a molecular marker predicting the presence of prolactinoma and may be useful for the diagnosis. But large-scale research is needed to clarify its role in diagnosis of prolactinoma patients.

Small-molecule survivin inhibitor YM155 enhances radiosensitization in esophageal squamous cell carcinoma by the abrogation of G2 checkpoint and suppression of homologous recombination repair

Background

Survivin is overexpressed in cancer cells and plays a crucial role in apoptosis evasion. YM155, a small-molecule inhibitor of survivin, could enhance the cytotoxicity of various DNA-damaging agents. Here, we evaluated the radiosensitizaion potential of YM155 in human esophageal squamous cell carcinoma (ESCC).

Methods

Cell viability was determined by CCK8 assay. The radiosensitization effect of YM155 was evaluated by clonogenic survival and progression of tumor xenograft. Cell cycle progression was determined by flow cytometric analysis. Radiation-induced DNA double strand break (DSB) and homologous recombination repair (HRR) were detected by the staining of γ-H2AX and RAD51, respectively. Expression of survivin and cell cycle regulators was detected by Western blot analysis.

Results

YM155 induced radiosensitization in ESCC cell lines Eca109 and TE13, associated with the abrogation of radiation induced G₂/M checkpoint, impaired Rad51 focus formation, and the prolongation of γ-H2AX signaling. G₂/M transition markers, including the activation of cyclinB1/Cdc2 kinase and the suppression of Cdc2 Thr14/Tyr15 phosphorylation were induced by YM155 in irradiated cells. The combination of YM155 plus irradiation delayed the growth of ESCC tumor xenografts to a greater extent compared with either treatment modality alone.

Conclusions

Our findings suggest that the abrogation of G₂ checkpoint and the inhibition of HRR contribute to radiosensitization by YM155 in ESCC cells.