Prognostic factors in laryngeal carcinoma: the role of apoptosis, p53, proliferation (Ki-67) and angiogenesis

Prognostic Value of Microvessel Density in Head and Neck Squamous Cell Carcinoma: A Meta-Analysis

The prognostic value of microvessel density (MVD) in head and neck squamous cell carcinoma (HNSCC) remains disputable. The purpose of this study was to comprehensively determine the prognostic value of MVD in HNSCC. Relevant literatures were identified using PubMed, Embase, and Cochrane Library. A meta-analysis was performed to clarify the prognostic role of MVD in HNSCC patients and different subgroups. A total of 14 eligible articles were included in this meta-analysis. The combined hazard ratio (HR) and 95% confidence interval (95% CI) for overall survival (OS) of 11 studies was 1.663 (1.236-2.237, P = 0.001), and the pooled HR and 95% CI for progression-free survival (PFS) of 7 studies was 2.069 (1.281-3.343, P = 0.003). Subgroup analyses were also performed on different issues, such as regional distribution of patients, age, tumor location, antibody, and treatment strategy. To conclude, high MVD is associated with worse OS and PFS in patients with HNSCC.

The Relevance of Assessing the Cell Proliferation Factor Ki-67 in Squamous Cell Carcinoma of the Larynx

The aim of study was to investigate the expression of the proliferation factor Ki-67 and its relationship with histological grade, cancer stage, and treatment outcome in squamous cell carcinoma of the larynx. Samples from 78 patients with laryngeal cancer were analysed retrospectively. Paraffin sections of tumors were immunohistochemically stained for Ki-67 expression. The patients were divided in two groups according to the proliferative factor values (a low Ki-67 index group - Ki-67≤34 and high Ki-67 index group-Ki-67 >34). Statistical analysis of the data shows significant correlation among histological tumor grade and the value of the Ki-67 proliferative index. There was no correlation between tumoral Ki-67 expression and diagnosis, stage of the disease, or treatment outcome. In conclusion, Ki-67 expression in laryngeal cancer is not the most reliable marker for making precise diagnosis and predicting the clinical course.

CD31 and VEGF are prognostic biomarkers in early-stage, but not in late-stage, laryngeal squamous cell carcinoma

Background

Patients suffering from squamous cell carcinoma of the larynx (LSCC) with lymphatic metastasis have a relatively poor prognosis and often require radical therapeutic management. The mechanisms which drive metastasis to the lymph nodes are largely unknown but may be promoted by a pro-angiogenic tumor microenvironment. In this study, we examined whether the number of microvessels and the expression level of vascular endothelial growth factor (VEGF) in the primary tumor are correlated with the degree of lymph node metastasis (N-stage), tumor staging (T) and survival time in LSCC patients.

Methods

Tissue-Microarrays of 97 LSCC patients were analyzed using immunohistochemistry. The expression of VEGF was scored as intensity of staining (low vs high) and the number of CD31-positive vessels (median </≥7 vessels per visual field) was counted manually. Scores were correlated with N-stage, T-stage and 5-year overall survival rate.

Results

A high expression of angiogenic biomarkers was not associated with poor overall survival in the overall cohort of patients. Instead high CD31 count was associated with early stage cancer (p = 0.004) and in this subgroup high VEGF expression correlated with poor survival (p = 0.032). Additionally, in early stage cancer a high vessel count was associated with an increased recurrence rate (p = 0.004).

Conclusion

Only in the early stage subgroup a high expression of angiogenic biomarkers was associated with reduced survival and an increased rate of recurrence. Thus, biomarkers of angiogenesis may be useful to identify high risk patients specifically in early stage LSCC.

Ki-67 is overexpressed in human laryngeal carcinoma and contributes to the proliferation of HEp2 cells

Ki-67 is one of the most useful markers to evaluate cell proliferative activity and has been widely used in tumor treatment and research. However, its role in human laryngeal carcinoma remains poorly defined. The aim of the present study was to investigate the expression of Ki-67 in human laryngeal squamous carcinoma and the effect of Ki-67 gene silencing by small interfering (si)RNA on the proliferation of human laryngocarcinoma HEp2 cells. Immunohistochemistry and reverse transcription-quantitative polymerase chain reaction were performed to examine the expression of Ki-67 in human laryngeal squamous carcinoma tissues and adjacent non-cancer tissues from 50 patients with laryngeal squamous carcinoma. RNA interference was used to knock down the expression of Ki-67 in the HEp2 cell line, and the proliferation of the treated cells was observed in vitro. Western blot analysis was used to determine the expression levels of epidermal growth factor receptor (EGFR) and E-cadherin in the treated cells. The expression of Ki-67 in the laryngeal squamous carcinoma tissues was significantly higher than that of the adjacent non-tumor tissues (P=0.028). The high expression of Ki-67 in cancer was significantly correlated with cervical lymph node metastasis and clinical outcomes (all P<0.001). The silencing of Ki-67 resulted in the inhibition of proliferation of the HEp2 human laryngocarcinoma cells (P<0.001). In addition, compared with the control group, the expression levels of EGFR and E-cadherin in the Ki-67 siRNA-treated cells were significantly decreased (P<0.001) and increased (P<0.001), respectively. These results suggested that Ki-67 is important in regulating the proliferation of human laryngocarcinoma HEp2 cells and that the mechanism may at least partially be associated with the upregulation of EGFR and the downregulation of E-cadherin. Overall, Ki-67 can be used as an important indicator for judging clinical progress and estimating prognosis in human laryngeal squamous carcinoma.

Apoptosis and expression of argyrophilic nucleolus organizer regions in epithelial neoplasms of the larynx

Introduction

Occurrence of apoptosis and expression of proliferative markers are powerful tools to establish a prognosis in the follow-up of cancer.

Objective

To evaluate the growth fraction in papillomas and laryngeal squamous cell carcinomas with three degrees of differentiation through apoptosis and the expression of nucleolus organizer regions.

Methods

Retrospective study from which paraffin material was submitted to microtomy and hematoxylin–eosin and silver staining. Stained slides were used to quantify the apoptotic index and the number of nucleolus organizer regions by morphometry.

Results

Apoptosis was significantly more frequent in well differentiated carcinomas and in papillomas, and a higher growth fraction of expressed nucleolus organizer regions and cells that expressed a greater than average number of nucleolus organizer regions were more frequently noted in undifferentiated carcinomas.

Conclusions

Thus, it was possible to verify that a high apoptotic index was associated with a lower chance of tumor differentiation in carcinomas, while a greater number of total nucleolus organizer regions, cells expressing nucleolus organizer regions above average and a higher growth fraction were associated with greater likelihood of abnormal cell proliferation and increased tumor differentiation.

The clinical relevance of Ki-67 expression in laryngeal squamous cell carcinoma

The aim of this study was to determine the prognostic value of Ki-67 immunostaining in patients affected by laryngeal squamous cell carcinoma. A systematic review was carried out in a tertiary university referral center. An appropriate string was run on PubMed to retrieve articles dealing with Ki-67 immunohistochemical staining and laryngeal squamous cell carcinoma. A double cross-check was performed on citations and full-text articles by two investigators independently to review all manuscripts and perform a comprehensive quality assessment. Of 85 abstracts identified, 18 articles were included. These studies reported on 1,342 patients with histological confirmed diagnosis of laryngeal squamous cell carcinoma. Most studies showed a statistical association between Ki-67 immunohistochemical expression and at least one of the clinical and histopathological parameters considered by the authors. Overall the studies analyzed suggested that the tumoral proliferative index was statistically connected respectively with T stage (2/18), N stage (4/18), grading (6/18), disease-free survival (10/18) and overall survival (4/18). Our review strongly suggests that immunohistochemical staining of Ki-67 correlates with tumoral aggressiveness and worse prognosis in patients affected by laryngeal squamous cell carcinoma. Further high-quality prospective studies should be carried out to confirm our finding and determine the eventual differences between cancers of specific laryngeal subsites.

99mTc-HYNIC-Annexin A5 in Oncology: Evaluating Efficacy of Anti-Cancer Therapies

Evaluation of efficacy of anti-cancer therapy is currently performed by anatomical imaging (e.g., MRI, CT). Structural changes, if present, become apparent 1-2 months after start of therapy. Cancer patients thus bear the risk to receive an ineffective treatment, whilst clinical trials take a long time to prove therapy response. Both patient and pharmaceutical industry could therefore profit from an early assessment of efficacy of therapy. Diagnostic methods providing information on a functional level, rather than a structural, could present the solution. Recent technological advances in molecular imaging enable in vivo imaging of biological processes. Since most anti-cancer therapies combat tumors by inducing apoptosis, imaging of apoptosis could offer an early assessment of efficacy of therapy. This review focuses on principles of and clinical experience with molecular imaging of apoptosis using Annexin A5, a widely accepted marker for apoptosis detection in vitro and in vivo in animal models. 99mTc-HYNIC-Annexin A5 in combination with SPECT has been probed in clinical studies to assess efficacy of chemo- and radiotherapy within 1-4 days after start of therapy. Annexin A5-based functional imaging of apoptosis shows promise to offer a personalized medicine approach, now primarily used in genome-based medicine, applicable to all cancer patients.

Expression of ABC transporters is an unfavorable prognostic factor in laryngeal squamous cell carcinoma

OBJECTIVES

Two prominent and well-characterized representatives of adenosine triphosphate-binding cassette (ABC) transporter - breast cancer resistance protein (BCRP or ABCG2) and P-glycoprotein (P-gp or ABCB1) - are known to be membrane transporters associated with multidrug resistance. The aim of this study was to explore the correlation between ABC transporter expression and the clinicopathologic characteristics, proliferative index, and apoptotic index and their prognostic value in laryngeal squamous cell carcinoma (LSCC).

METHODS

Paraffin sections of 98 human LSCC specimens were investigated with immunohistochemical techniques. The relationship between ABCG2 and ABCB1 expression and clinicopathologic parameters, proliferative activities, and apoptotic activities and their prognostic value in patients' overall survival rate were subsequently analyzed.

RESULTS

Immunohistochemical analysis revealed positive expression of ABCG2 and ABCB1 in 52.0% and 41.8% of patients, respectively. There was a positive correlation between ABCG2 expression and ABCB1 expression. The presence of these two proteins was significantly related to clinical stage, lymph node metastasis, and overall survival in LSCC. Interestingly, up-regulation of ABCG2 expression was found to be associated with increased proliferation, but that of ABCB1 was not. Up-regulation of both ABCG2 expression and ABCB1 expression was associated with decreased apoptosis.

CONCLUSIONS

The results of this study revealed that the presence of ABCG2 and/or ABCB1 is predictive for malignant progression and is an independent prognostic factor in LSCC. The mechanism of ABC transporters may contribute to chemotherapy resistance by promoting proliferation and/or suppressing apoptosis.

Effect of apoptotic and proliferative indices, P-glycoprotein and survivin expression on prognosis in laryngeal squamous cell carcinoma

This study was to explore the relationship between P-glycoprotein and survivin expression with apoptotic index, proliferative index, clinicopathologic characteristics, and their prognostic value in laryngeal squamous cell carcinoma (LSCC). Samples from 86 patients with LSCC were analyzed for P-glycoprotein, survivin, and Ki-67 expression by immunohistochemistry and apoptotic index by the TUNEL method. The association of P-glycoprotein and survivin expression with clinicopathologic parameters, apoptotic and proliferative activities, and patients' overall survival was subsequently analyzed. We found that up-regulation of P-glycoprotein expression was associated with decreased apoptosis but not with changes in proliferation, whereas increased survivin expression was correlated with decreased apoptosis and increased proliferation. There was a positive correlation between P-glycoprotein and survivin expression. Expression of these two proteins was significantly related to the clinical stage, histological grade, lymph node metastasis, and overall survival in LSCC. These results reveal that survivin and P-glycoprotein may have an effect on chemotherapy resistance and progression of LSCC through promoting proliferation and/or suppressing apoptosis. Furthermore, our results demonstrate that P-glycoprotein and survivin proteins are both predictive of malignant progression and prognosis of LSCC.

A hybrid machine learning-based method for classifying the Cushing's Syndrome with comorbid adrenocortical lesions

BACKGROUND

The prognosis for many cancers could be improved dramatically if they could be detected while still at the microscopic disease stage. It follows from a comprehensive statistical analysis that a number of antigens such as hTERT, PCNA and Ki-67 can be considered as cancer markers, while another set of antigens such as P27KIP1 and FHIT are possible markers for normal tissue. Because more than one marker must be considered to obtain a classification of cancer or no cancer, and if cancer, to classify it as malignant, borderline, or benign, we must develop an intelligent decision system that can fullfill such an unmet medical need.

RESULTS

We have developed an intelligent decision system using machine learning techniques and markers to characterize tissue as cancerous, non-cancerous or borderline. The system incorporates learning techniques such as variants of support vector machines, neural networks, decision trees, self-organizing feature maps (SOFM) and recursive maximum contrast trees (RMCT). These variants and algorithms we have developed, tend to detect microscopic pathological changes based on features derived from gene expression levels and metabolic profiles. We have also used immunohistochemistry techniques to measure the gene expression profiles from a number of antigens such as cyclin E, P27KIP1, FHIT, Ki-67, PCNA, Bax, Bcl-2, P53, Fas, FasL and hTERT in several particular types of neuroendocrine tumors such as pheochromocytomas, paragangliomas, and the adrenocortical carcinomas (ACC), adenomas (ACA), and hyperplasia (ACH) involved with Cushing's syndrome. We provided statistical evidence that higher expression levels of hTERT, PCNA and Ki-67 etc. are associated with a higher risk that the tumors are malignant or borderline as opposed to benign. We also investigated whether higher expression levels of P27KIP1 and FHIT, etc., are associated with a decreased risk of adrenomedullary tumors. While no significant difference was found between cell-arrest antigens such as P27KIP1 for malignant, borderline, and benign tumors, there was a significant difference between expression levels of such antigens in normal adrenal medulla samples and in adrenomedullary tumors.

CONCLUSIONS

Our frame work focused on not only different classification schemes and feature selection algorithms, but also ensemble methods such as boosting and bagging in an effort to improve upon the accuracy of the individual classifiers. It is evident that when all sorts of machine learning and statistically learning techniques are combined appropriately into one integrated intelligent medical decision system, the prediction power can be enhanced significantly. This research has many potential applications; it might provide an alternative diagnostic tool and a better understanding of the mechanisms involved in malignant transformation as well as information that is useful for treatment planning and cancer prevention.

Prognostic value of 99mTc-HYNIC Annexin-V imaging in squamous cell carcinoma of the head and neck

PURPOSE

The purpose of the study was to report on the prognostic value of (99m)Tc-hydrazinonicotinamide (HYNIC) Annexin-V single-photon emission computed tomography (SPECT) imaging in patients suffering from primary squamous cell carcinoma of the head and neck.

METHODS

Twenty-nine patients diagnosed with a primary untreated head and neck squamous cell carcinoma were included in this study. In all patients, (99m)Tc-HYNIC Annexin-V scintigraphy SPECT was performed before treatment instigation. Tumour-to-background ratios (T/N) of the primary tumour, derived from reconstructed images, as well as clinical variables were obtained in all patients and related to patient outcome. Median follow-up was 22.6 months (range 4.1-55.8 months).

RESULTS

On univariate as well as multivariate analysis, only the (99m)Tc-HYNIC Annexin-V T/N ratio dichotomized using the group median as cutoff value (T/N ratio of 2) was predictive of recurrence-free survival (respectively, p = 0.0000 and 0.000). On univariate analysis, only lymph node status dichotomized according to N0 vs N1-N2-N3 disease and the (99m)Tc-HYNIC Annexin-V T/N ratio dichotomized using the group median as cutoff value (T/N ratio of 2) were predictive of overall survival (p = 0.0051 and 0.0000). When both factors were included in the multivariate model, both N status and the (99m)Tc-HYNIC Annexin-V T/N ratio showed an independent association with overall survival (p = 0.001 for lymph node status and 0.000 for dichotomized (99m)Tc-HYNIC Annexin-V T/N ratio).

CONCLUSION

(99m)Tc-HYNIC Annexin-V T/N ratios derived from SPECT provides independent prognostic information on disease-free survival and overall survival.

Molecular markers of head and neck squamous cell carcinoma: promising signs in need of prospective evaluation

BACKGROUND

The aim of this article is to review recent developments in the biological understanding of head and neck squamous cell carcinomas.

METHODS AND RESULTS

We describe the markers according to their function and their prognostic or predictive roles. Some associations can be found between molecular markers and invasiveness, aggressiveness, degree of differentiation, and tumor stage, but only a few clinical studies have shown an impact on prognosis. In addition, despite an increasing number of articles relating to this topic, the small number of patients included in the studies reported reduces the clinical implications of these results. Few studies applied a more comprehensive molecular analysis approach, such as DNA microarrays or differential expression profiling by polymerase chain reaction, to identify a combination of markers that could be more informative than a single molecular marker.

CONCLUSION

Some progress has been made with respect to molecular markers and head and neck cancers. Translational and prospective, hypothesis-driven research must proceed with sufficient rigor to facilitate the clinical applicability of such results.

Selective reporting biases in cancer prognostic factor studies

BACKGROUND

Nonreported and selectively reported information and the use of different definitions may introduce biases in the literature of prognostic factors. We probed these biases in a meta-analysis of a prognostic factor for head and neck squamous cell cancer (HNSCC) mortality that has drawn wide attention--the status of the tumor suppressor protein TP53.

METHODS

We compared results of meta-analyses that included published data plus unpublished data retrieved from investigators; published data; and only published data indexed with "survival" or "mortality" in MEDLINE/EMBASE, with or without standardized definitions. We also evaluated whether previously published meta-analyses on mortality predictors for various malignancies addressed issues of retrieval and standardized information. All statistical tests were two-sided.

RESULTS

For the 18 studies with 1364 patients that included published and indexed data, we obtained a highly statistically significant association between TP53 status and mortality. When we used the definitions preferred by each publication, the association was stronger (risk ratio [RR] = 1.38, 95% confidence interval [CI] = 1.13 to 1.67; P = .001) than when we standardized definitions (RR = 1.27, 95% CI = 1.06 to 1.53; P = .011). The addition of 13 studies with 1028 subjects that included published but not indexed data reduced the observed association (RR = 1.23, 95% CI = 1.03 to 1.47; P = .02). Finally, when we obtained data from investigators (11 studies with 996 patients) and analyzed it with all other data, statistical significance was lost (RR = 1.16, 95% CI = 0.99 to 1.35; P = .06). Among 18 published meta-analyses of 37 cancer prognostic factors, 13 (72%) did not use standardized definitions and 16 (89%) did not retrieve additional information.

CONCLUSIONS

Selective reporting may spuriously inflate the importance of postulated prognostic factors for various malignancies. We recommend that meta-analyses thereof should maximize retrieval of information and standardize definitions.