Jeffrey N. Myers

Exome Sequencing of Head and Neck Squamous Cell Carcinoma Reveals Inactivating Mutations in NOTCH1

The mutational profile of head and neck cancer is complex and may pose challenges to the development of targeted therapies. Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. To explore the genetic origins of this cancer, we used whole-exome sequencing and gene copy number analyses to study 32 primary tumors. Tumors from patients with a history of tobacco use had more mutations than did tumors from patients who did not use tobacco, and tumors that were negative for human papillomavirus (HPV) had more mutations than did HPV-positive tumors. Six of the genes that were mutated in multiple tumors were assessed in up to 88 additional HNSCCs. In addition to previously described mutations in TP53, CDKN2A, PIK3CA, and HRAS, we identified mutations in FBXW7 and NOTCH1. Nearly 40% of the 28 mutations identified in NOTCH1 were predicted to truncate the gene product, suggesting that NOTCH1 may function as a tumor suppressor gene rather than an oncogene in this tumor type.

Integrative Genomic Characterization of Oral Squamous Cell Carcinoma Identifies Frequent Somatic Drivers

The survival of patients with oral squamous cell carcinoma (OSCC) has not changed significantly in several decades, leading clinicians and investigators to search for promising molecular targets. To this end, we conducted comprehensive genomic analysis of gene expression, copy number, methylation, and point mutations in OSCC. Integrated analysis revealed more somatic events than previously reported, identifying four major driver pathways (mitogenic signaling, Notch, cell cycle, and TP53) and two additional key genes (FAT1, CASP8). The Notch pathway was defective in 66% of patients, and in follow-up studies of mechanism, functional NOTCH1 signaling inhibited proliferation of OSCC cell lines. Frequent mutation of caspase-8 (CASP8) defines a new molecular subtype of OSCC with few copy number changes. Although genomic alterations are dominated by loss of tumor suppressor genes, 80% of patients harbored at least one genomic alteration in a targetable gene, suggesting that novel approaches to treatment may be possible for this debilitating subset of head and neck cancers.

Inhibition of growth and survival of human head and neck squamous cell carcinoma cells by curcumin via modulation of nuclear factor-κB signaling

Increased expression of proinflammatory and proangiogenic factors are associated with aggressive tumor growth and decreased survival of patients with head and neck squamous cell carcinoma (HNSCC). In as much as genes that are regulated by nuclear factor NF‐κB suppress apoptosis, induce proliferation, and mediate inflammation, angiogenesis and tumor metastasis, agents that suppress NF‐κB activation have potential as treatment for various cancers including HNSCC. We demonstrate that all HNSCC cell lines expressed constitutively active NF‐κB and IκBα kinase (IKK), which is needed for NF‐κB activation. Treatment of MDA 686LN cells with curcumin (diferuloylmethane), a pharmacologically safe chemopreventive agent, inhibited NF‐κB activation through abrogation of IKK. As a result expression of various cell survival and cell proliferative genes including Bcl‐2, cyclin D1, IL‐6, COX‐2 and MMP‐9 was suppressed. This, in turn, inhibits proliferation of all HNSCC cell lines, arrests cell cycle in G1/S phase (MDA 686LN) and induces apoptosis as indicated by upstream and downstream caspase activation, PARP cleavage, annexin V staining in MDA 686LN cells. Suppression of NF‐κB by cell‐permeable p65‐based peptide and NBD peptide also inhibited the proliferation and induced apoptosis in these cells. Our results indicate that curcumin is a potent inhibitor of cell proliferation and an inducer of apoptosis in HNSCC through suppression of IKK‐mediated NF‐κB activation and of NF‐κB‐regulated gene expression.

Metastasis of squamous cell carcinoma of the oral tongue

Squamous cell carcinoma of the oral tongue (SCCOT) is one of the most prevalent tumors of the head and neck region. Despite advances in treatment, the survival of patients with SCCOT has not significantly improved over the past several decades. Most frequently, treatment failure takes the form of local and regional recurrences, but as disease control in these areas improves, SCCOT treatment failures are occurring more often as distant metastasis. The presence of cervical lymph node metastasis is the most reliable adverse prognostic factor in patients with SCCOT, and extracapsular spread (ECS) of cervical lymph nodes metastasis is a particularly reliable predictor of regional and distant recurrence and death from disease. Decisions regarding the elective and therapeutic management of cervical lymph node metastases are made mainly on clinical grounds as we cannot always predict cervical lymph node metastasis from the size and extent of invasion of the primary tumors. Therefore, the treatment of these metastases in the management of SCCOT remains controversial. The promise of basing treatment decisions on biomarkers has yet to be fully realized because of our poor understanding of the mechanisms of regional and distant metastases of SCCOT. Here we summarize the current status of investigations of SCCOT metastases and the potential of these studies to have a positive impact on the clinical management of SCCOT in the future.

Squamous cell carcinoma of the tongue in young adults: Increasing incidence and factors that predict treatment outcomes

OBJECTIVE This study was designed to determine whether the incidence of squamous cell carcinoma of the oral tongue (SCCOT) in young adults has changed during the past 25 years and to determine prognostic factors for young adult patients (aged < 40 years) with SCCOT. METHODS AND PATIENTS A retrospective review of young adults with SCCOT who sought treatment at the M. D. Anderson Cancer Center between 1973 and 1995 was undertaken. RESULTS The percentage of young adult SCCOT patients at M. D. Anderson increased from 4% in 1971 to 18% in 1993. T stage, N stage, perineural invasion, and lymphatic invasion were all associated with decreased survival. Patients who received a neck dissection as part of their primary treatment had a better chance of survival than patients who did not. CONCLUSIONS The incidence of SCCOT in the young adult population is increasing in the United States. Appropriate surgical management for young adults with SCCOT includes resection of the primary tumor along with a selective node dissection. (Otolaryngol Head Neck Surg 2000;122:44–51.)

Sentinel lymph node biopsy accurately stages the regional lymph nodes for T1-T2 oral squamous cell carcinomas: results of a prospective multi-institutional trial.

PURPOSE The validity of sentinel lymph node biopsy (SLNB) for T1 or T2, clinically N0, oral cancer was tested by correlation of sentinel node pathologic status with that of nodes within the completion neck dissection. METHODS This prospective, cooperative group trial involved 25 institutions over a 3-year period. One hundred forty patients with invasive oral cancers, stage T1 and T2, N0 including 95 cancers of the tongue, 26 of the floor of mouth, and 19 other oral cancers were studied. The study excluded lesions with diameter smaller than 6 mm or minimal invasion. Imaging was used to exclude nonpalpable gross nodal disease. Patients underwent injection of the lesion with (99m)Tc-sulfur colloid, nuclear imaging, narrow-exposure SLNB, and completion selective neck dissection. The major end point was the negative-predictive value (NPV) of SLNB. RESULTS In the 106 SLNBs, which were found to be pathologically and clinically node-negative by routine hematoxylin and eosin stain, 100 patients were found to have no other pathologically positive nodes, corresponding to a NPV of 94%. With additional sectioning and immunohistochemistry, NPV was improved to 96%. In the forty patients with proven cervical metastases, the true-positive rate was 90.2% and was superior for tongue tumors relative to floor of mouth. For T1 lesions, metastases were correctly identified in 100%. CONCLUSION For T1 or T2 N0 oral squamous cell carcinoma, SLNB with step sectioning and immunohistochemistry, performed by surgeons of mixed experience levels, correctly predicted a pathologically negative neck in 96% of patients (NPV, 96%).

Extent of extracapsular spread: a critical prognosticator in oral tongue cancer.

Extracapsular spread (ECS) of metastatic squamous cell carcinoma of the head and neck to regional lymph nodes is the most reliable predictor of poor treatment outcomes. Recently, the authors have shown that ECS is significantly associated with higher rates of locoregional recurrence, distant metastasis, and decreased survival in patients with squamous cell carcinoma of the oral tongue (SCCOT). The purpose of this review was to determine if the degree of ECS impacts distant metastasis rates and survival.

Predictors of Weight Loss During Radiation Therapy

OBJECTIVE: To define risk factors for weight loss or dehydration during radiation therapy (RT). STUDY DESIGN AND SETTING: Retrospective chart review, academic tertiary care center. RESULTS: The incidence of severe weight loss during RT was 32.7%, the incidence of dehydration was 10.9%, and the rate of prophylactic feeding gas-trostomy tube placement was 32%. The patients most likely to suffer severe weight loss included patients with tumor sites of nasopharynx and base of tongue, those treated with chemoradiation, and patients with severe pretreatment weight loss. Prophylactic feeding gastrostomy tube placement before RT significantly reduced the incidence of severe weight loss and hospitalization during RT. CONCLUSION: Severe weight loss and dehydration during RT for head and neck cancer is common. Prophylactic feeding gastrostomy tubes significantly reduce the incidence of severe weight loss and hospitalization for dehydration during RT when placed before onset of RT. Patients at risk for severe weight loss include those with severe pretreatment weight loss, tumors of the nasopharynx and base of tongue, or treatment with chemoradiation.

TP53 Disruptive Mutations Lead to Head and Neck Cancer Treatment Failure through Inhibition of Radiation-Induced Senescence

Purpose: Mortality of patients with head and neck squamous cell carcinoma (HNSCC) is primarily driven by tumor cell radioresistance leading to locoregional recurrence (LRR). In this study, we use a classification of TP53 mutation (disruptive vs. nondisruptive) and examine impact on clinical outcomes and radiation sensitivity. Experimental Design: Seventy-four patients with HNSCC treated with surgery and postoperative radiation and 38 HNSCC cell lines were assembled; for each, TP53 was sequenced and the in vitro radioresistance measured using clonogenic assays. p53 protein expression was inhibited using short hairpin RNA (shRNA) and overexpressed using a retrovirus. Radiation-induced apoptosis, mitotic cell death, senescence, and reactive oxygen species (ROS) assays were carried out. The effect of the drug metformin on overcoming mutant p53-associated radiation resistance was examined in vitro as well as in vivo, using an orthotopic xenograft model. Results: Mutant TP53 alone was not predictive of LRR; however, disruptive TP53 mutation strongly predicted LRR (P = 0.03). Cell lines with disruptive mutations were significantly more radioresistant (P < 0.05). Expression of disruptive TP53 mutations significantly decreased radiation-induced senescence, as measured by SA-β-gal staining, p21 expression, and release of ROS. The mitochondrial agent metformin potentiated the effects of radiation in the presence of a disruptive TP53 mutation partially via senescence. Examination of our patient cohort showed that LRR was decreased in patients taking metformin. Conclusions: Disruptive TP53 mutations in HNSCC tumors predicts for LRR, because of increased radioresistance via the inhibition of senescence. Metformin can serve as a radiosensitizer for HNSCC with disruptive TP53, presaging the possibility of personalizing HNSCC treatment. Clin Cancer Res; 18(1); 290–300. ©2011 AACR.

Prognostic significance of microscopic and macroscopic extracapsular spread from metastatic tumor in the cervical lymph nodes

It has been established that the presence or absence of cervical node metastases in patients with head and neck squamous cell carcinoma (HNSCC) is a powerful prognostic indicator. This report reviews the evolution of thinking over the past 70 years with regard to the import and detection of cervical nodal metastases which exhibit spread of tumor beyond the confines of the original encompassing nodal capsule. In the process, this discussion touches upon clinical examination, gross and microscopic pathologic examination, and radiographic imaging studies. In particular, the distinction between gross nodal extracapsular spread of tumor and microscopic nodal extracapsular spread of tumor has been drawn in recent reports; this raises the possibility that identification of microscopic breaching of the nodc capsule by tumor might provide clinically significant information which is not provided by the gross observation of an intact lymph node capsule. While it remains to be seen whether microscopic extracapsular spread alone will prove to be an important prognostic factor, it is recommended that selective neck dissection continue to be offered even in those patients with clinically negative necks; further studies should aid in defining the import of microscopic extracapsular tumor spread in patients with positive cervical nodes.