Analyses of Bcl-2, Survivin, and CD44v6 expressions and human papillomavirus infection in cervical carcinomas

Prevalence and Prognostic Value of HPV among Tunisian Patients with Laryngeal Cancer and Relationship between DNA HPV and p16, IGF-1R, Survivin, p53 Expressions

OBJECTIVES

Tobacco and alcohol are the main etiological factors common to laryngeal cancers. However, the Human Papilloma Virus (HPV) constitutes an alternative risk factor according to several studies. In Tunisia, despite the annual increasing incidence of laryngeal squamous cell carcinoma (LSCC), the prevalence and prognostic significance of HPV have never been explored.In this study, we sought to highlight HPV DNA in 70 biopsies of laryngeal cancer, and to analyze the status of HPV infection in association with p53, p16, survivin, and IGF-1R expressions.

METHODS

HPV high risk (HPV HR) DNA was detected in tumors by in situ hybridization. However, the expression of p53, p16, survivin and IGF-1R were stained by immunohistochemistry test. The correlations of HPV status with clinicopathological parameters, overall survival, disease-free survival and proteins expressions were statistically evaluated.

RESULTS

HPV HR DNA was detected in 39 out of 70 (55.71%) laryngeal tumors. HPV+ patients have a better overall survival (P = .081) and long disease-free-survival (P = .016) with a low rate of recurrence (P = .006) than HPV^- patients. No significant correlations were found between HPV HR status and clinicopathological parameters (all P > .005). Moreover, HPV+ tumors were not associated with expression of p53, p16 and survivin. However, HPV HR status correlates with weak to moderate IGF-1R expression (P = .043).

CONCLUSION

The substantial detection of HPV HR in LSCC tumors suggest that this virus plays an important part in laryngeal cancer in Tunisia. It is a good prognostic factor. In addition, HPV infection could act to block the pathway of IGF-1R expression.

Inhibitors of apoptosis: clinical implications in cancer

Inhibitor of apoptosis (IAP) family comprises a group of endogenous proteins that function as main regulators of caspase activity and cell death. They are considered the main culprits in evasion of apoptosis, which is a fundamental hallmark of carcinogenesis. Overexpression of IAP proteins has been documented in various solid and hematological malignancies, rendering them resistant to standard chemotherapeutics and radiation therapy and conferring poor prognosis. This observation has urged their exploitation as therapeutic targets in cancer with promising pre-clinical outcomes. This review describes the structural and functional features of IAP proteins to elucidate the mechanism of their anti-apoptotic activity. We also provide an update on patterns of IAP expression in different tumors, their impact on treatment response and prognosis, as well as the emerging investigational drugs targeting them. This aims at shedding the light on the advances in IAP targeting achieved to date, and encourage further development of clinically applicable therapeutic approaches.

Clinicopathological significance of survivin expression in patients with cervical cancer: A systematic meta-analysis

BACKGROUND

Survivin has been shown to play an important role in cancer pathogenesis. However, its role in cervical cancer development is still controversial. This study was performed to evaluate the clinical significance of survivin expression in cervical cancer.

METHODS

Search of some online electronic databases was conducted to identify available studies. The pooled odds ratios (ORs) with its 95% confidence intervals (CIs) were calculated and analyzed.

RESULTS

Finally, 18 eligible studies with 791 cervical cancer patients, 1,013 cervical intraepithelial neoplasia (CIN) lesions, 199 normal cervical tissues, and 95 samples with chronic cervicitis were identified in this analysis. The pooled OR of survivin expression was found to be significantly higher in the samples from cervical cancer than in those from CIN lesions, normal cervical tissues, and chronic cervicitis. When cervical cancer was compared to CIN lesions, the subgroup analysis by ethnicity showed that survivin expression was associated with a risk of cervical cancer in Asians (P < 0.001), but not in Caucasians (P = 0.659). In addition, survivin was significantly more overexpressed in high-grade cervical cancer than in low-grade cervical cancer. Its expression was also more elevated in advanced-stage patients than in early-stage patients, in lymph node metastasis than in lymph node without metastasis, and in squamous cell carcinoma (SCC) than in adenocarcinoma (AC).

CONCLUSIONS

The expression of survivin may play a key role in the carcinogenesis, progression, and metastasis of cervical cancer. However, survivin expression may be involved in the progression of CIN lesions only in the Asian population. Survivin expression is associated with an increased risk of SCC. Additional studies with larger sample sizes are needed in the future to confirm our findings.

Survivin Overexpression Is Associated with Aggressive Clinicopathological Features in Cervical Carcinoma: A Meta-Analysis

Objective

Overexpression of survivin has been reported in many human tumors. However, the clinicopathological features associated with survivin overexpression in cervical carcinoma remain controversial. Thus, the current meta-analysis was performed to assess the clinicopathological significance of survivin in cervical carcinoma.

Methods

PubMed, EMBASE, and Web of Science databases were searched for relevant studies published through November 1, 2015. A meta-analysis was performed to evaluate the association between survivin expression and clinicopathological outcome in cervical carcinoma.

Results

Eleven eligible studies with a total of 865 patients were included. Survivin overexpression was closely related to lymph node metastasis (odds ratio [OR] = 0.679, 95% confidence interval [CI]: 0.509–0.905, P = 0.008) but was not significantly associated with tumor FIGO stage (I+II vs. III+IV) (OR = 0.843, 95% CI: 0.626–1.137, P = 0.264), tumor grade (G1+G2 vs. G3) (OR = 0.913, 95% CI: 0.689–1.210, P = 0.527), tumor size (>4 vs. ≤4 cm) (OR = 0.825, 95% CI: 0.434–1.570, P = 0.559), or stromal involvement (OR = 0.820, 95% CI: 0.545–1.233, P = 0.340). The correlation between survivin expression and overall survival was evaluated among a total of 238 patients from three eligible studies. The pooled HR was 1.129 (95% CI: 0.597–1.661; P = 0.000), indicating that survivin expression was significantly associated with poor survival in cervical carcinoma.

Conclusions

Based on the current meta-analysis, survivin is strongly associated with lymph node metastasis and poor prognosis. Additionally, survivin is a novel clinicopathological marker of cervical carcinoma and thus may be a therapeutic target for cervical carcinoma.

Inflammation-Related DNA Damage and Cancer Stem Cell Markers in Nasopharyngeal Carcinoma

Nitrative and oxidative DNA damage plays an important role in inflammation-related carcinogenesis. To investigate the involvement of stem cells in Epstein-Barr virus infection-related nasopharyngeal carcinoma (NPC), we used double immunofluorescence staining to examine several cancer stem/progenitor cell markers (CD44v6, CD24, and ALDH1A1) in NPC tissues and NPC cell lines. We also measured 8-nitroguanine formation as an indicator of inflammation-related DNA lesions. The staining intensity of 8-nitroguanine was significantly higher in cancer cells and inflammatory cells in the stroma of NPC tissues than in chronic nasopharyngitis tissues. Expression levels of CD44v6 and ALDH1A1 were significantly increased in cancer cells of primary NPC specimens in comparison to chronic nasopharyngitis tissues. Similarly, more intense staining of CD44v6 and ALDH1A1 was detected in an NPC cell line than in an immortalized nasopharyngeal epithelial cell line. In the case of CD24 staining, there was no significant difference between NPC and chronic nasopharyngitis tissues. 8-Nitroguanine was detected in both CD44v6- and ALDH1A1-positive stem cells in NPC tissues. In conclusion, CD44v6 and ALDH1A1 are candidate stem cell markers for NPC, and the increased formation of DNA lesions by inflammation may result in the mutation of stem cells, leading to tumor development in NPC.

Cancer spheres from gastric cancer patients provide an ideal model system for cancer stem cell research

Cancer stem cells have been hypothesized to drive the growth and metastasis of tumors. Because they need to be targeted for cancer treatment, they have been isolated from many solid cancers. However, cancer stem cells from primary human gastric cancer tissues have not been isolated as yet. For the isolation, we used two cell surface markers: the epithelial cell adhesion molecule (EpCAM) and CD44. When analyzed by flow cytometry, the EpCAM(+)/CD44(+) population accounts for 4.5% of tumor cells. EpCAM(+)/CD44(+) gastric cancer cells formed tumors in immunocompromised mice; however, EpCAM(-)/CD44(-), EpCAM(+)/CD44(-) and EpCAM(-)/CD44(+) cells failed to do so. Xenografts of EpCAM(+)/CD44(+) gastric cancer cells maintained a differentiated phenotype and reproduced the morphological and phenotypical heterogeneity of the original gastric tumor tissues. The tumorigenic subpopulation was serially passaged for several generations without significant phenotypic alterations. Moreover, EpCAM(+)/CD44(+), but not EpCAM(-)/CD44(-), EpCAM(+)/CD44(-) or EpCAM(-)/CD44(+) cells grew exponentially in vitro as cancer spheres in serum-free medium, maintaining the tumorigenicity. Interestingly, a single cancer stem cell generated a cancer sphere that contained various differentiated cells, supporting multi-potency and self-renewal of a cancer stem cell. EpCAM(+)/CD44(+) cells had greater resistance to anti-cancer drugs than other subpopulation cells. The above in vivo and in vitro results suggest that cancer stem cells, which are enriched in the EpCAM(+)/CD44(+) subpopulation of gastric cancer cells, provide an ideal model system for cancer stem cell research.

Survivin and telomerase expression in the uterine cervix of women with human papillomavirus-induced lesions

INTRODUCTION

Infection by human papillomavirus is the most important risk factor in the pathogenesis of uterine cervical cancer. The aims of this study were to evaluate the expression of survivin protein and telomerase enzyme in samples of uterine cervix from women with human papillomavirus-induced lesions and to determine the relationship between survivin and telomerase expression and the different grades of cervical squamous intraepithelial neoplasia and invasive cervical carcinoma.

METHODS

Biopsy samples from the uterine cervix of 105 women aged 18 to 80 years were analyzed. The patients were divided into 5 groups: WN group, 20 patients without neoplasia; CIN-1 group, 24 patients with grade 1 cervical intraepithelial neoplasia (CIN), grade 1; CIN-2 group, 20 patients with CIN grade 2; CIN-3 group, 24 patients with CIN, grade 3; and ICC group, 17 patients with invasive cervical carcinoma. Human papillomavirus detection, telomerase activity, and survivin expression were assessed using polymerase chain reaction (PCR), real-time PCR (RT-PCR), and immunochemistry, respectively.

RESULTS

There was a significant increase in the expression of telomerase and survivin associated with the severity of the lesion.

CONCLUSIONS

The results suggest that mechanisms that promote both cell proliferation (telomerase activity) and cell survival (survivin expression) are active in cervical cancer and its precursor lesions. There was a negative correlation between survivin expression and the number of PCR cycles necessary to detect telomerase activity in the total sample, achieving statistical significance in patients in the CIN-3 group.

Molecular markers implicating early malignant events in cervical carcinogenesis

BACKGROUND

Human papillomavirus can induce a stepwise progression of precursor lesions to carcinoma. Sensitive and specific molecular markers are needed to identify the cervical lesions (CIN) at risk for this progression. hTERT activation could be one indicator of a point of no return in malignant progression.

METHODS

The UT-DEC-1 cell line is an in vitro model for the study of human papillomavirus-induced progression. Using molecular mining, nine potential genes interlinking hTERT and viral oncogene expression with the phenotypical features of CIN2 were identified. After preliminary testing with real-time PCR, five genes were selected for further analysis: hTERT, DKC1, Bcl-2, S100A8, and S100A9. These proteins were also tested in a series of 120 CIN lesions using immunohistochemistry.

RESULTS

Analysis of the mRNA expression of these genes at different cell passages revealed three time points with significant changes. hTERT, Bcl-2, and S100A9 were also overexpressed in CIN lesions, and the expression pattern changed during the progression toward CIN3 lesions.

CONCLUSIONS

These identified time points that were combined with the mRNA overexpression of target genes matched events previously shown to be important in the progression toward malignancy: (a) the viral integration into the cell genome and episome loss; (b) the selection of cells with an acquired growth advantage and ability to maintain telomerase activity; and (c) the final stage of malignancy with permanently upregulated telomerase.

IMPACT

hTERT, Bcl-2, and S100A9 together might compose a potential prognostic marker panel for the assessment of CIN lesions. These results, however, need further validation in prospective clinical settings. (c)2010 AACR.