Jan Akervall

Toxicities and costs of placing prophylactic and reactive percutaneous gastrostomy tubes in patients with locally advanced head and neck cancers treated with chemoradiotherapy

We compared dependence rates, complications, toxicities, and costs associated with prophylactic versus reactive percutaneous endoscopic gastrostomy (PEG) tube placement.

Genomic screening of head and neck cancer and its implications for therapy planning

Despite great technical improvements in radiotherapy and surgery, survival for patients with squamous cell carcinoma of the head and neck (SCCHN) has still not improved significantly over the last decades. Management of SCCHN has mainly been based on the TNM staging and site over this time period, even though we know that there are individual differences independent of the TNM status. Individual patients with small tumors might have a poor outcome, and patients with large tumors may end up with a favorable prognosis, despite their respective TNM classification. Recent molecular studies indicate that underlying genetic abnormalities may reflect such individual differences independently of TNM status. Individualization of treatment based on such biological properties of the tumors might result in less over as well as under treatment. However, the optimal panel of biomarkers to be used for the individualization of treatment is yet to be defined. A variety of laboratory techniques have been used in studies that investigate the individual biological features, spanning from methods that screen the genome for chromosomal and genetic abnormalities, e.g., cytogenetics, CGH, SKY and cDNA micro array, to detailed studies of specific aberrations. The purpose of this review of the literature is to summarize what has been studied so far by methods for genetic screening and to relate these results to the prediction of the clinical outcome. We conclude that it is time to focus future prospective studies on how treatment can be individualized based on biomarkers in combination with the macroscopic features of SCCHN.

c-Met Expression Is a Marker of Poor Prognosis in Patients With Locally Advanced Head and Neck Squamous Cell Carcinoma Treated With Chemoradiation

PURPOSE To examine the prognostic significance of c-Met expression in relation to p16 and epidermal growth factor receptor (EGFR) in patients with locally advanced head and neck squamous cell carcinoma (HNSCC) treated with definitive concurrent chemoradiation. METHODS AND MATERIALS Archival tissue from 107 HNSCC patients treated with chemoradiation was retrieved, and a tissue microarray was assembled. Immunohistochemical staining of c-Met, p16, and EGFR was performed. c-Met expression was correlated with p16, EGFR, clinical characteristics, and clinical endpoints including locoregional control (LRC), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS). RESULTS Fifty-one percent of patients were positive for p16, and 53% were positive for EGFR. Both p16-negative (P≤.001) and EGFR-positive (P=.019) status predicted for worse DFS. Ninety-three percent of patients stained positive for c-Met. Patients were divided into low (0, 1, or 2+ intensity) or high (3+ intensity) c-Met expression. On univariate analysis, high c-Met expression predicted for worse LRC (hazard ratio [HR] 2.27; 95% CI, 1.08-4.77; P=.031), DM (HR 4.41; 95% CI, 1.56-12.45; P=.005), DFS (HR 3.00; 95% CI, 1.68-5.38; P<.001), and OS (HR 4.35; 95% CI, 2.13-8.88; P<.001). On multivariate analysis, after adjustment for site, T stage, smoking history, and EGFR status, only high c-Met expression (P=.011) and negative p16 status (P=.003) predicted for worse DFS. High c-Met expression was predictive of worse DFS in both EGFR-positive (P=.032) and -negative (P=.008) patients. In the p16-negative patients, those with high c-Met expression had worse DFS (P=.036) than did those with low c-Met expression. c-Met expression was not associated with any outcome in the p16-positive patients. CONCLUSIONS c-Met is expressed in the majority of locally advanced HNSCC cases, and high c-Met expression predicts for worse clinical outcomes. High c-Met expression predicted for worse DFS in p16-negative patients but not in p16-positive patients. c-Met predicted for worse outcome regardless of EGFR status.

Isolation and genomic characterization of stem cells in head and neck cancer.

This study investigated the use of 3 different established cell‐sorting strategies to isolate and characterize stem cells from head and neck cancer cell lines.

Cancer Stem Cell Signaling during Repopulation in Head and Neck Cancer

The aim of the study was to investigate cancer stem signaling during the repopulation response of a head and neck squamous cell cancer (HNSCC) xenograft after radiation treatment. Xenografts were generated from low passage HNSCC cells and were treated with either sham radiation or 15 Gy in one fraction. At different time points, days 0, 3, and 10 for controls and days 4, 7, 12, and 21, after irradiation, 3 tumors per group were harvested for global gene expression, pathway analysis, and immunohistochemical evaluation. 316 genes were identified that were associated with a series of stem cell-related genes and were differentially expressed (p ≤ 0.01 and 1.5-fold) at a minimum of one time point in UT-SCC-14 xenografts after radiation. The largest network of genes that showed significant changes after irradiation was associated with CD44, NOTCH1, and MET. c-MET and ALDH1A3 staining correlated with the changes in gene expression. A clear pattern emerged that was consistent with the growth inhibition data in that genes associated with stem cell pathways were most active at day 7 and day 12 after irradiation. The MET/CD44 axis seemed to be an important component of the repopulation response.

Evaluation of genetic biomarkers for distinguishing benign from malignant thyroid neoplasms

BACKGROUND Fine-needle aspiration (FNA) aids in the diagnosis of thyroid nodules. The expression of previously implicated genes was examined to potentially discriminate between benign and malignant thyroid samples. METHODS Patients included for study had cytology demonstrating follicular cells of undetermined significance, atypical cells of undetermined significance, follicular neoplasm, or suspicion of malignancy with one of the following postoperative diagnoses: follicular thyroid adenomas, follicular thyroid carcinomas, or follicular variant of papillary thyroid carcinomas (FV-PTCs). FNA and tumor expression of human telomerase reverse transcriptase (hTERT), high-mobility group A2 (HMGA2), and trefoil factor 3/3-galactoside-binding lectin (T/G ratio) were analyzed. RESULTS T/G ratios were not significantly different in the malignant and benign groups. HMGA2 was overexpressed in carcinoma states; however, only FV-PTCs were significant (P = .006). Tumor hTERT expression was detected in 25% of follicular thyroid carcinomas, whereas 5% of FV-PTCs and 10% of follicular thyroid adenomas had expression. FNA aspirates showed similar results. CONCLUSIONS Although HMGA2 and hTERT showed differential expression, they did not consistently differentiate benign from malignant. Further study based on global gene expression is needed to identify markers that could serve as a diagnostic tool.

SPIN: Development of Sample-specific Protein Integrity Numbers as an Index of Biospecimen Quality

It is widely accepted that variable biorepository specimen handling conditions can significantly alter outcomes of clinical research studies, suggesting the need for a metric for sample analyte protein integrity. In line with the National Cancer Institute (NCI) Best Practices, it is vital that the integrity of specimens used for biomarker studies are of the highest standard to ensure validity of the data they generate and confidence in the application of new findings to clinical management. We describe the creation of a program to discover proteins in biorepository samples that can be utilized to assess the integrity of stored specimens for protein-based biomarker studies, similar to the universally accepted quality metric for RNA, the RNA Integrity Number, or RIN. The study mimics potential variation in pre-analytical conditions which may result in proteolysis and other proteome-associated changes and employs surface-enhanced laser desorption time-of-flight mass spectrometry (SELDI-TOF MS) to assess changes in multiple proteins and peptides in a high-throughput manner. Candidate peaks from SELDI spectra of representative sample types (e.g., serum, urine, tissue extracts) which demonstrate differing but reproducible sensitivity to suboptimal processing and storage were selected and quantified in a series of specimens stored in the BioBank within the Beaumont Health System. We then assigned a relative index known here as Sample-specific Protein Integrity Number, or SPIN, which is derived from a ratio of nonstable vs. stable proteins for each sample type in the investigation. This methodology can be applied to every sample type and, once refined and established, the SPIN could be used by any biobank or laboratory using biobanked samples without specialized equipment and irrespective of the sample pre-analytical collection conditions.

Gene Expression Characterization of HPV Positive Head and Neck Cancer to Predict Response to Chemoradiation

Human papillomavirus (HPV) has been shown to have a causal role in the development of head and neck squamous cell carcinoma. While HPV-positive head and neck cancer is associated with a better response to treatment in the majority of patients, there is a subset who does not respond favorably to current therapy. Identification of these patients could prevent unnecessary morbidity and indicate the need for alternative therapeutic options. Tissue samples were obtained from 19 patients with HPV-positive head and neck squamous carcinoma treated with chemoradiation therapy. HPV status was confirmed by polymerase chain reaction analysis through detection of HPV16 E7 in both DNA and RNA. RNA was isolated from tissue samples and subjected to microarray gene expression analysis. In addition to identification of potential genetic biomarkers (including LCE3D, KRTDAP, HMOX1, KRT19, MDK, TSPAN1), differentially expressed genes associated with genomic stability, cell cycle, and DNA damage were detected between responders and non-responders. These results were further validated with publicly available gene expression studies. This pilot study suggests prospective biomarkers that predict response to therapy. The importance of genes involved with genomic stability is highlighted in both development and progression of head and neck squamous cell carcinoma but also recurrence. Potential development of an assay may prove beneficial to clinicians, assisting them to provide alternative care sooner thus lowering morbidity.

Gene expression changes during repopulation in a head and neck cancer xenograft

BACKGROUND/PURPOSE To investigate temporal changes in global gene expression and pathways involved in the response to irradiation during phases of growth inhibition, recovery and repopulation in a human head and neck squamous cell cancer (HNSCC) xenograft. METHODS AND MATERIALS Low passage head and neck squamous cancer cells (UT-14-SCC) were injected into the flanks of female nu/nu mice to generate xenografts. After tumors reached a size of 500 mm3, they were treated with either sham RT or 15Gy in one fraction. At different time points, days 0, 3, and 10 for controls and days 4, 7, 12, and 21 after irradiation, the tumors were harvested for global gene expression analysis and pathway analysis. RESULTS The tumors showed growth inhibition through days 4-7 and began the transition to regrowth around the day 12 time point. When comparing the pooled controls to each day of treatment, there were 22, 119, 125, and 25 differentially expressed genes on days 4, 7, 12, and 21 respectively using a p⩽0.01 and a 2-fold cut-off. Gene Ontology (GO), gene set enrichment analysis (GSEA) and sub-network enrichment analysis (SNEA) identified different biological processes, cell process pathways and expression targets to be active on each time point after irradiation. An important observation was that the molecular events on day 12 which represented the transition from growth inhibition to regrowth identified interferon and cytokine related genes and signaling pathways as the most prominent. CONCLUSION The findings in this study compliment research which has identified components of interferon-related signaling pathways to be involved in radioresistance. Further work will be required to understand the significance of these genes in both radioresistance and treatment response leading to new therapeutic strategies and prognostic tools.

Beaumont Health System BioBank: A Multidisciplinary Biorepository and Translational Research Facility

The Beaumont BioBank model is a multidisciplinary facility that is designed to provide access and opportunity for research-minded clinicians to become involved in research without the need for their own research infrastructure, thus increasing the research effort across the Health System. We describe a biobank model that works primarily in operating rooms for tissue collection and utilizes a generic consent process to facilitate rapid and accurate collection of biospecimens. The model combines both a biorepository that collects specimens based on clinical questions and also a translational research facility that undertakes biomarker-based research on those specimens in a seamless and efficient process. We believe that the Beaumont BioBank model would be readily applicable and reproducible in other academic healthcare systems.