Prediction of survival of HPV16-negative, p16-negative oral cavity cancer patients using a 13-gene signature: A multicenter study using FFPE samples

OBJECTIVES

To test the performance of an oral cancer prognostic 13-gene signature for the prediction of survival of patients diagnosed with HPV-negative and p16-negative oral cavity cancer.

MATERIALS AND METHODS

Diagnostic formalin-fixed paraffin-embedded oral cavity cancer tumor samples were obtained from the Fred Hutchinson Cancer Research Center/University of Washington, University of Calgary, University of Michigan, University of Utah, and seven ARCAGE study centers coordinated by the International Agency of Research on Cancer. RNA from 638 Human Papillomavirus (HPV)-negative and p16-negative samples was analyzed for the 13 genes using a NanoString assay. Ridge-penalized Cox regressions were applied to samples randomly split into discovery and validation sets to build models and evaluate the performance of the 13-gene signature in predicting 2-year oral cavity cancer-specific survival overall and separately for patients with early and late stage disease.

RESULTS

Among AJCC stage I/II patients, including the 13-gene signature in the model resulted in substantial improvement in the prediction of 2-year oral cavity cancer-specific survival. For models containing age and sex with and without the 13-gene signature score, the areas under the Receiver Operating Characteristic Curve (AUC) and partial AUC were 0.700 vs. 0.537 (p < 0.001), and 0.046 vs. 0.018 (p < 0.001), respectively. Improvement in predicting prognosis for AJCC stage III/IV disease also was observed, but to a lesser extent.

CONCLUSIONS

If confirmed using tumor samples from a larger number of early stage oral cavity cancer patients, the 13-gene signature may inform personalized treatment of early stage HPV-negative and p16-negative oral cavity cancer patients.

Telomere Length and Lung Cancer Mortality among Heavy Smokers

Background: Accumulating evidence suggests that short telomere length is associated with increased overall mortality, but the relationship with cancer mortality is less clear. We examined whether telomere length (global, and chromosome arm 5p- and 13q-specific) is associated with lung cancer mortality among cases from the β-Carotene and Retinol Efficacy Trial of heavy smokers.Methods: Telomere length was measured on average 6 years before diagnosis for 788 lung cancer cases. Adjusted Cox proportional hazards models of all-cause and lung cancer-specific mortality were assessed for lung cancer overall and by histotype.Results: Short telomere length was associated with increased mortality for small cell lung cancer (SCLC), particularly stage III/IV SCLC [HR and 95% confidence interval for shortest vs. longest telomere length tertile: 3.32 (1.78-6.21)]. Associations were strongest for those randomized to the active intervention and when telomere length was measured ≤5 years before diagnosis. All-cause mortality patterns were similar. Short chromosome 5p telomere length was suggestively associated with lung cancer mortality, but there was no association with chromosome 13q telomere length.Conclusions: Our large prospective study suggests that among heavy smokers who developed lung cancer, short prediagnosis telomere length is associated with increased risk of death from SCLC.Impact: This is the first study to examine telomere length and mortality in lung cancer cases by histotype. If the association between short telomere length and SCLC mortality is replicated, elucidation of mechanisms through which telomere length influences survival for this highly aggressive cancer may inform more effective use of telomere-targeted therapeutics. Cancer Epidemiol Biomarkers Prev; 27(7); 829-37. ©2018 AACR.

Muscle Quality Improves with Extended High-Intensity Resistance Training after Hip Fracture

BACKGROUND

Muscle mass deficits endure after hip fracture. Strategies to improve muscle quality may improve mobility and physical function. It is unknown whether training after usual care yields muscle quality gains after hip fracture.

OBJECTIVES

To determine whether muscle quality improves after hip fracture with high-intensity resistance training and protein supplementation.

DESIGN

Case series.

SETTING

University of Utah Skeletal Muscle Exercise Research Facility.

PARTICIPANTS

17 community-dwelling older adults, 3.6+/-1.1 months post-hip fracture, recently discharged from usual-care physical therapy (mean age 77.0+/-12.0 years, 12 female), enrolled.

INTERVENTION

Participants underwent 12 weeks (3x/week) of unilaterally-biased resistance training.

METHODS/MATERIALS

Participants were measured via a 3.0 Tesla whole-body MR imager for muscle lean and intramuscular adipose tissue (IMAT) of the quadriceps before and after resistance training. Peak isometric knee extension force output was measured with an isokinetic dynamometer. Muscle quality was calculated by dividing peak isometric knee extension force (N) by quadriceps lean muscle mass (cm2). In addition, common physical function variables were measured before and after training.

RESULTS

Surgical and nonsurgical lean quadriceps muscle mass improved among participants (mean change: 2.9 cm2+/-1.4 cm2, and 2.7 cm2+/-1.3 cm2, respectively), while IMAT remained unchanged. Peak force improved in the surgical limb by 43.1+/-23N, with no significant change in the nonsurgical limb. Significant gains in physical function were evident after training.

CONCLUSION

Participants recovering from hip fracture demonstrated improvements in muscle mass, muscle strength, and muscle quality in the surgical limb after hip fracture. These were in addition to gains made in the first months after fracture with traditional care. Future studies should determine the impact that muscle quality has on long-term functional recovery in this population.

Nested case-control study of telomere length and lung cancer risk among heavy smokers in the β-Carotene and Retinol Efficacy Trial

Background

Telomeres protect cells from genomic instability. We examined telomere length and lung cancer risk prospectively in heavy smokers.

Methods

In a nested case–control study with 709 cases and 1313 controls, conditional logistic regression was used to evaluate associations between telomere length (global, chromosome 5p, and 13q) and lung cancer risk by histotype, controlling for detailed smoking history.

Results

Risks of overall lung cancer and adenocarcinoma were suggestively elevated among individuals with telomere length in the longest tertile. No clear patterns were observed for other histotypes, or for chromosome 5p or 13q telomere length. Associations with adenocarcinoma were strongest among (OR, 95% CI for longest versus shortest tertile): former smokers (2.26, 1.03–4.96), individuals <65 years (2.22, 1.13–4.35), and women (2.21, 0.99–4.93).

Conclusions

Our large study of heavy smokers adds additional evidence that long telomere length prior to diagnosis is associated with risk of lung adenocarcinoma, but not other histotypes.

Transcriptome analysis reveals differentially expressed lncRNAs between oral squamous cell carcinoma and healthy oral mucosa

Oral cavity and oropharyngeal squamous cell carcinoma (OSCC) is a major cancer type in the head and neck region. To better understand the roles long non-coding RNA (lncRNA) play in OSCC carcinogenesis, we compared the expression levels of 3,054 probe sets for lncRNAs between 167 OSCCs and 45 healthy oral mucosa using an Affymetrix HG U133 plus 2.0 array dataset. We found 658 lncRNA transcripts (790 probe sets) to be significantly differentially expressed using a criteria of FDR < 0.01, with 36 of them (39 probe sets) showing more than a 2-fold change. We further validated the top differentially expressed lncRNAs in three independent datasets from Gene Expression Omnibus (GEO) repository: GSE42743, GSE9844, and GSE6791. Fourteen lncRNAs (15 probe sets) were validated in all three datasets using the criteria FDR < 0.01: LOC441178, C5orf66-AS1, HCG22, FLG-AS1, CCL14/CCL15-CCL14, LOC100506990, TRIP10, PCBP1-AS1, LINC01315, LINC00478, COX10-AS1/LOC100506974, MLLT4-AS1, MIR31HG, and DUXAP10/LINC01296. Three lncRNAs in the validated list which showed the highest fold change (LOC441178, HCG22 and C5orf66-AS1) were verified by quantitative RT-PCR in a subset of 20 OSCCs and 10 control samples. In silico prediction of their functional role has given us directions for further investigation.

High-Intensity Multimodal Resistance Training Improves Muscle Function, Symmetry during a Sit-to-Stand Task, and Physical Function Following Hip Fracture

OBJECTIVES

Post rehabilitation, older adults with hip fracture display low vertical ground reaction force (vGRF) on the involved lower extremity during a sit-to-stand task and low physical function. The purpose of this study was to test whether muscle performance, involved side vGRF during a sit-to-stand task, and physical function improved following multimodal high-intensity resistance training, when initiated after usual care (2 to 6 months after hip fracture).

DESIGN

Case series study, 12 weeks extended high-intensity strength training intervention following hip fracture.

SETTING

University hospital outpatient facility.

PARTICIPANTS

Twenty-four community-dwelling older adults (mean age 78.4 years (SD 10.4), 16 female/8 male), 3.6 (SD 1.2) months post-hip fracture and discharged from physical therapy participated. Intervention/Measurement: All participants performed sit-to-stand tasks, muscle performance tests, and modified physical performance test (mPPT) before and after 12 weeks (3x/wk) of training. Variables were compared using paired t-tests.

RESULTS

The vGRF rate of force development (RFD) and magnitude of discrepancy between limb loading during rising phase of sit-to-stand task (AREA) variables improved post-training (RFD ratio = Pre: 0.78 - Post: 0.82, AREA ratio = Pre: 0.79 - Post: 0.86). Surgical leg extension power gains were large (~65%) while strength gains were moderate (~34%); yielding improved symmetry in both strength (Pre: 0.74 - Post: 0.88) and power (Pre: 0.75 - Post: 0.82). Physical function improved pre-training 25 (SD 5.2) to post training 30 (SD 4.3), (p < 0.001).

CONCLUSION

Unique to this study, participants recovering from hip fracture demonstrated improved symmetry in sit-to-stand vGRFs, muscle function, and physical function after training. However, a high percentage of patients continued to experience persistently low vGRF of the involved side compared to previous studies of healthy elderly controls. Developing alternative strategies to improve involved side vGRF may be warranted.

Abstract 3503: Transcriptome analysis reveals differentially expressed lncRNAs between oral squamous cell carcinoma and healthy oral mucosa

Objective: Oral cavity and oropharyngeal squamous cell carcinoma (OSCC) is a major cancer type in the head and neck region. To better understand the roles long non-coding RNA (lncRNA) play in OSCC carcinogenesis, we compared the genome-wide gene expressions of lncRNA in OSCC and in the oral mucosa from healthy individuals.

Materials and methods: We compared the expression levels of 3,054 probe sets for lncRNAs between 167 OSCCs and 45 healthy controls using an Affymetrix HG U133 plus 2.0 array dataset. We validated the top differentially expressed lncRNAs in three independent datasets in the Gene Expression Omnibus (GEO) repository: GSE42743, GSE9844, and GSE6791. We further tested the differential expression of the three lncRNAs showing the highest fold change by quantitative RT-PCR in a subset of 20 OSCCs and 10 control samples.

Results: We found 658 lncRNA transcripts (790 probe sets) to be significantly differentially expressed between OSCC and healthy oral mucosa using a criteria of FDR&lt;0.01, with 36 of them (39 probe sets) showing more than a 2-fold change. Among the 36, 14 (15 probe sets) lncRNAs were validated in all three independent datasets using the criteria FDR&lt;0.01: LOC441178, C5orf66-AS1, HCG22, FLG-AS1, CCL14/CCL15-CCL14, LOC100506990, TRIP10, PCBP1-AS1, LINC01315, LINC00478, COX10-AS1/LOC100506974, MLLT4-AS1, MIR31HG, and DUXAP10/LINC01296. The differential expressions of LOC441178, HCG22 and C5orf66-AS1 were verified by qRT-PCR.

Conclusion: We identified a number of differentially expressed lncRNAs using transcriptomic data between OSCCs and healthy oral mucosa. Further investigations into their potential role in OSCC carcinogenesis or to serve as OSCC biomarkers and/or therapeutic targets are warranted.

Citation Format: Lu Feng, John R. Houck, Pawadee Lohavanichbutr, Chu Chen. Transcriptome analysis reveals differentially expressed lncRNAs between oral squamous cell carcinoma and healthy oral mucosa [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3503. doi:10.1158/1538-7445.AM2017-3503

Genome-Wide Loss of Heterozygosity and DNA Copy Number Aberration in HPV-Negative Oral Squamous Cell Carcinoma and Their Associations with Disease-Specific Survival

Oral squamous cell cancer of the oral cavity and oropharynx (OSCC) is associated with high case-fatality. For reasons that are largely unknown, patients with the same clinical and pathologic staging have heterogeneous response to treatment and different probability of recurrence and survival, with patients with Human Papillomavirus (HPV)-positive oropharyngeal tumors having the most favorable survival. To gain insight into the complexity of OSCC and to identify potential chromosomal changes that may be associated with OSCC mortality, we used Affymtrix 6.0 SNP arrays to examine paired DNA from peripheral blood and tumor cell populations isolated by laser capture microdissection to assess genome-wide loss of heterozygosity (LOH) and DNA copy number aberration (CNA) and their associations with risk factors, tumor characteristics, and oral cancer-specific mortality among 75 patients with HPV-negative OSCC. We found a highly heterogeneous and complex genomic landscape of HPV-negative tumors, and identified regions in 4q, 8p, 9p and 11q that seem to play an important role in oral cancer biology and survival from this disease. If confirmed, these findings could assist in designing personalized treatment or in the creation of models to predict survival in patients with HPV-negative OSCC.

Integrative genomics in combination with RNA interference identifies prognostic and functionally relevant gene targets for oral squamous cell carcinoma

In oral squamous cell carcinoma (OSCC), metastasis to lymph nodes is associated with a 50% reduction in 5-year survival. To identify a metastatic gene set based on DNA copy number abnormalities (CNAs) of differentially expressed genes, we compared DNA and RNA of OSCC cells laser-microdissected from non-metastatic primary tumors (n = 17) with those from lymph node metastases (n = 20), using Affymetrix 250K Nsp single-nucleotide polymorphism (SNP) arrays and U133 Plus 2.0 arrays, respectively. With a false discovery rate (FDR)<5%, 1988 transcripts were found to be differentially expressed between primary and metastatic OSCC. Of these, 114 were found to have a significant correlation between DNA copy number and gene expression (FDR<0.01). Among these 114 correlated transcripts, the corresponding genomic regions of each of 95 transcripts had CNAs differences between primary and metastatic OSCC (FDR<0.01). Using an independent dataset of 133 patients, multivariable analysis showed that the OSCC–specific and overall mortality hazards ratio (HR) for patients carrying the 95-transcript signature were 4.75 (95% CI: 2.03–11.11) and 3.45 (95% CI: 1.84–6.50), respectively. To determine the degree by which these genes impact cell survival, we compared the growth of five OSCC cell lines before and after knockdown of over-amplified transcripts via a high-throughput siRNA–mediated screen. The expression-knockdown of 18 of the 26 genes tested showed a growth suppression ≥30% in at least one cell line (P<0.01). In particular, cell lines derived from late-stage OSCC were more sensitive to the knockdown of G3BP1 than cell lines derived from early-stage OSCC, and the growth suppression was likely caused by increase in apoptosis. Further investigation is warranted to examine the biological role of these genes in OSCC progression and their therapeutic potentials.

Neck lymph node metastasis is the most important prognostic factor in oral squamous cell carcinoma (OSCC). To identify genes associated with this critical step of OSCC progression, we compared DNA copy number aberrations and gene expression differences between tumor cells found in metastatic lymph nodes versus those in non-metastatic primary tumors. We identified 95 transcripts (87 genes) with metastasis-specific genome abnormalities and gene expression. Tested in an independent cohort of 133 OSCC patients, the 95 gene signature was an independent risk factor of disease-specific and overall death, suggesting a disease progression phenotype. We knocked down the expression of over-amplified genes in five OSCC cell lines. Knockdown of 18 of the 26 tested genes suppressed the cell growth in at least one cell line. Interestingly, cell lines derived from late-stage OSCC were more sensitive to the knockdown of G3BP1 than cell lines derived from early-stage OSCC. The knockdown of G3BP1 increased programmed cell death in the p53-mutant but not wild-type OSCC cell lines. Taken together, we demonstrate that CNA–associated transcripts differentially expressed in carcinoma cells with an aggressive phenotype (i.e., metastatic to lymph nodes) can be biomarkers with both prognostic information and functional relevance. Moreover, results suggest that G3BP1 is a potential therapeutic target against late-stage p53-negative OSCC.

Integrative analysis in oral squamous cell carcinoma reveals DNA copy number-associated miRNAs dysregulating target genes

OBJECTIVE

To better understand possible mechanisms involved in the dysregulation of gene expression unique to oral squamous cell carcinoma (OSCC) metastasis, the investigators examined the differential expression of microRNAs (miRNAs) in OSCC metastasis and their functional impact on target gene expression.

STUDY DESIGN

Observational assessment of DNA copy number, miRNA, and RNA expression in primary and metastatic OSCC.

SETTING

University of Washington Medical Center and affiliated hospitals.

SUBJECTS

Tumor samples were taken from patients with primary incident OSCC; cells were laser-capture microdissected from 17 nonmetastatic primary tumors and 20 metastatic lymph nodes.

METHODS

DNA copy number aberrations and gene expression profiles were previously determined using Affymetrix 250K Nsp I SNP arrays and HU133 plus 2.0 expression arrays. miRNAs were interrogated with Exiqon's Ready-to-Use PCR Panels assessing the expression of 368 human miRNAs.

RESULTS

Investigators found 31 miRNAs differentially expressed between metastatic and nonmetastatic samples (false discovery rate <0.4; 26 overexpressed and 5 underexpressed in metastatic samples). Expression of 7 of these miRNAs was significantly associated with their DNA copy numbers, and expressions of 8 of these miRNAs were significantly associated with their target genes. Among these unique miRNAs, miR-140-3p, miR-29c, and miR-29a were differentially expressed in metastasis versus nonmetastatic samples and had a strong positive correlation with their DNA copy numbers and a negative correlation with the expression of their target genes.

CONCLUSION

Results suggest that DNA copy number aberration may play a role in the dysregulation of some differentially expressed miRNAs in OSCC metastasis, warranting further investigation.

Tumor and salivary matrix metalloproteinase levels are strong diagnostic markers of oral squamous cell carcinoma

BACKGROUND

The matrix metalloproteinases (MMP) cause degradation of the extracellular matrix and basement membranes, and thus may play a key role in cancer development.

METHODS

In our search for biomarkers for oral squamous cell carcinomas (OSCC), we compared primary OSCC, oral dysplasia and control subjects with respect to: (i) expression of MMP1, MMP3, MMP10, and MMP12 in oral epithelial tissue using Affymetrix U133 2.0 Plus GeneChip arrays, followed by quantitative reverse transcription-PCR (qRT-PCR) for MMP1, and (ii) determination of MMP1 and MMP3 concentrations in saliva.

RESULTS

MMP1 expression in primary OSCC (n = 119) was >200-fold higher (P = 7.16 × 10(-40)) compared with expression levels in nonneoplastic oral epithelium from controls (n = 35). qRT-PCR results on 30 cases and 22 controls confirmed this substantial differential expression. The exceptional discriminatory power to separate OSCC from controls was validated in two independent testing sets (AUC% = 100; 95% CI: 100-100 and AUC% = 98.4; 95% CI: 95.6-100). Salivary concentrations of MMP1 and MMP3 in OSCC patients (33 stage I/II, 26 stage III/IV) were 6.2 times (95% CI: 3.32-11.73) and 14.8 times (95% CI: 6.75-32.56) higher, respectively, than in controls, and displayed an increasing trend with higher stage disease.

CONCLUSION

Tumor and salivary MMPs are robust diagnostic biomarkers of OSCC.

IMPACT

The capacity of MMP gene expression to identify OSCC provides support for further investigation into MMPs as potential markers for OSCC development. Detection of MMP proteins in saliva in particular may provide a promising means to detect and monitor OSCC noninvasively.

Abstract 4983: Integrative analysis of DNA copy number and gene expression identifies G3BP1 and HIRA as potential therapeutic targets against metastatic oral squamous cell carcinoma

The presence of lymph node metastasis is associated with a 50% reduction of 5-year survival in patients with oral squamous cell carcinoma (OSCC). We set out to combine DNA copy number aberrations (CNAs) with gene expression profiles, to identify CNAs-associated genes dysregulated in metastatic OSCC, and determine whether these genes can be targeted to selectively kill metastatic OSCC tumor cells. Toward this end, we interrogated DNA and RNA of the same OSCC cell populations laser micro-dissected from non-metastatic primary tumors (n=17) and metastatic lymph nodes (n=20) using Affymetrix 250K Nsp single-nucleotide polymorphism (SNP) arrays and U133 Plus 2.0 arrays, respectively. With a false discovery rate (FDR) &lt; 5%, 1988 transcripts were found to be differentially expressed between primary and metastatic OSCC. Out of these, 114 transcripts showed significant correlation between their DNA copy number alternations (estimated using SNPs within 250 kb upstream and downstream of the transcript) and gene expression (FDR &lt; 0.01). Among these CNA-correlated transcripts, 95 had significantly different DNA copy numbers between metastatic and non-metastatic OSCC (FDR &lt;0.01 by Wilcoxon rank test). These 95 transcripts (representing 87 genes) mainly clustered around three genomic locations: 3p25.3-22.1, 9p24.1- 22.3 and 18q21.1-22.3. Among these 87 genes, we selected 28 of the 58 genes that were over-amplified and over-expressed in metastatic OSCC and conducted a high-throughput siRNA-mediated gene knockdown screen in five cell lines derived from primary and lymph node metastatic OSCC. The expression-knockdown of 18 genes showed 30% or more growth suppression in at least one cell line as compared to mock controls in which the cells were treated with transfection reagent only without the siRNA (P &lt; 0.01). In particular, knocking-down G3BP1 and HIRA selectively suppressed the growth of all OSCC cell lines derived from lymph node metastases when compared to non-metastatic lines. Further investigation is warranted to confirm these findings and to examine the biological role of G3BP1 and HIRA in OSCC metastasis and their potential as therapeutic targets.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4983. doi:10.1158/1538-7445.AM2011-4983

Can a metastatic gene expression profile outperform tumor size as a predictor of occult lymph node metastasis in oral cancer patients?

PURPOSE

To determine the differential gene expression between oral squamous cell carcinoma (OSCC) with and without metastasis to cervical lymph nodes and to assess prediction of nodal metastasis by using molecular features.

EXPERIMENTAL DESIGN

We used Affymetrix U133 2.0 plus arrays to compare the tumor genome-wide gene expression of 73 node-positive OSCCs with 40 node-negative OSCCs (≥ 18 months). Multivariate linear regression was used to estimate the association between gene expression and nodal metastasis. Stepwise logistic regression and receiver operating characteristics (ROC) analysis were used to generate predictive models and to compare these with models by using tumor size alone.

RESULTS

We identified five genes differentially expressed between node-positive and node-negative OSCCs after adjusting for tumor size and human papillomavirus status: REEP1, RNF145, CTONG2002744, MYO5A, and FBXO32. Stepwise regression identified a four-gene model (MYO5A, RFN145, FBXO32, and CTONG2002744) as the most predictive of nodal metastasis. A leave-one-out ROC analysis revealed that our model had a higher area under the curve (AUC) for identifying occult nodal metastasis compared with that of a model by tumor size alone (respective AUC: 0.85 and 0.61; P = 0.011). A model combining tumor size and gene expression did not further improve the prediction of occult metastasis. Independent validation using 31 metastatic and 13 nonmetastatic cases revealed a significant underexpression of CTONG2002744 (P = 0.0004).

CONCLUSIONS

These results suggest that our gene expression markers of OSCC metastasis hold promise for improving current clinical practice. Confirmation by others and functional studies of CTONG2002744 is warranted.

Integrative analysis of DNA copy number and gene expression in metastatic oral squamous cell carcinoma identifies genes associated with poor survival

Background

Lymphotropism in oral squamous cell carcinoma (OSCC) is one of the most important prognostic factors of 5-year survival. In an effort to identify genes that may be responsible for the initiation of OSCC lymphotropism, we examined DNA copy number gains and losses and corresponding gene expression changes from tumor cells in metastatic lymph nodes of patients with OSCC.

Results

We performed integrative analysis of DNA copy number alterations (CNA) and corresponding mRNA expression from OSCC cells isolated from metastatic lymph nodes of 20 patients using Affymetrix 250 K Nsp I SNP and U133 Plus 2.0 arrays, respectively. Overall, genome CNA accounted for expression changes in 31% of the transcripts studied. Genome region 11q13.2-11q13.3 shows the highest correlation between DNA CNA and expression. With a false discovery rate < 1%, 530 transcripts (461 genes) demonstrated a correlation between CNA and expression. Among these, we found two subsets that were significantly associated with OSCC (n = 122) when compared to controls, and with survival (n = 27), as tested using an independent dataset with genome-wide expression profiles for 148 primary OSCC and 45 normal oral mucosa. We fit Cox models to calculate a principal component analysis-derived risk-score for these two gene sets ('122-' or '27-transcript PC'). The models combining the 122- or 27-transcript PC with stage outperformed the model using stage alone in terms of the Area Under the Curve (AUC = 0.82 or 0.86 vs. 0.72, with p = 0.044 or 0.011, respectively).

Conclusions

Genes exhibiting CNA-correlated expression may have biological impact on carcinogenesis and cancer progression in OSCC. Determination of copy number-associated transcripts associated with clinical outcomes in tumor cells with an aggressive phenotype (i.e., cells metastasized to the lymph nodes) can help prioritize candidate transcripts from high-throughput data for further studies.

Abstract 2209: Integrative analysis of DNA copy number and gene expression in metastatic tumor cells from oral squamous cell carcinoma for the identification of genes associated with survival

To examine the impact of copy number aberrations (CNA) on gene expression in oral squamous cell carcinoma (OSCC) metastasis, we used Affymetrix 250K Nsp single nucleotide polymorphism arrays and U133 Plus 2.0 expression arrays, respectively, to interrogate the DNA and RNA from metastatic OSCC cells isolated using laser capture microdissection from lymph nodes of 20 patients. Overall, CNA accounted for expression changes in about 30% of the transcripts studied. With a false discovery rate &lt; 1%, 530 transcripts (461 genes) were identified as to have significantly correlated CNA and expression. When tested using an independent dataset with expression profiles for 148 primary OSCC and 45 normal oral mucosa, the genes were enriched with candidates associated with OSCC (vs. normal oral mucosa) (n=174 transcripts differentially expressed) and OSCC-specific survival (n=32 transcripts associated), as compared to a random gene set of the same size (p &lt; 0.001). We then fit two Cox models using the first two principal components derived from these two gene sets (‘174-transcript PCA’ or ‘32-transcript PCA’), and two other models that combined stage with either the 174- or the 32-transcript PCA score. The Area Under the Curve (AUC) for a model combining stage with 174-gene PCA was significantly higher than that for a model with stage alone (AUC=0.80 vs. 0.72, p = 0.042). Further investigation is warranted to confirm these findings and to examine the biologic role of these copy number-associated transcripts in OSCC metastasis and their potential as therapeutic targets.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2209.

The effect of acid suppression on upper airway anatomy and obstruction in patients with sleep apnea and gastroesophageal reflux disease

STUDY OBJECTIVES

This study was designed to assess the effect of acid suppression on upper airway structure and function in patients with obstructive sleep apnea syndrome (OSAS) and gastroesophageal reflux disease (GERD).

METHODS

This is a single-site within-subjects design. Twenty five patients with documented mild OSAS and objectively documented GERD via 24-hour pH measurement were included in the study. Patients were studied before and after 8 weeks of treatment with rabeprazole, 20 mg, twice a day. Subjects underwent laryngoscopy, polysomnography, and 24-hour pH monitoring. Subjective assessments of sleep obtained included the Pittsburg Sleep Quality Index and the Epworth Sleepiness Scale.

RESULTS

Posterior commissure edema was significantly reduced (p < 0.05), and the Reflux Finding Score was improved (p < 0.07). Objective and subjective sleep parameters were significantly improved, sleep-onset latency was significantly reduced (26.2 vs 11.2, p < 0.05), and sleep-related acid contact time was significantly reduced (8.0% vs 1.7% p < 0.001). There was no significant change in the apnea-hypopnea index.

CONCLUSIONS

In patients with mild OSAS and documented GERD, acid suppression improves upper airway abnormalities, as well as objective and subjective measures of sleep quality. Aggressive treatment of GERD in patients with OSAS may be helpful in the overall treatment of this select patient population.

A genetic expression profile associated with oral cancer identifies a group of patients at high risk of poor survival

PURPOSE

To determine if gene expression signature of invasive oral squamous cell carcinoma (OSCC) can subclassify OSCC based on survival.

EXPERIMENTAL DESIGN

We analyzed the expression of 131 genes in 119 OSCC, 35 normal, and 17 dysplastic mucosa to identify cluster-defined subgroups. Multivariate Cox regression was used to estimate the association between gene expression and survival. By stepwise Cox regression, the top predictive models of OSCC-specific survival were determined and compared by receiver operating characteristic analysis.

RESULTS

The 3-year overall mean+/-SE survival for a cluster of 45 OSCC patients was 38.7+/-0.09% compared with 69.1+/-0.08% for the remaining patients. Multivariate analysis adjusted for age, sex, and stage showed that the 45 OSCC patient cluster had worse overall and OSCC-specific survival (hazard ratio, 3.31; 95% confidence interval, 1.66-6.58 and hazard ratio, 5.43; 95% confidence interval, 2.32-12.73, respectively). Stepwise Cox regression on the 131 probe sets revealed that a model with a term for LAMC2 (laminin gamma2) gene expression best identified patients with worst OSCC-specific survival. We fit a Cox model with a term for a principal component analysis-derived risk score marker and two other models that combined stage with either LAMC2 or PCA. The area under the curve for models combining stage with either LAMC2 or PCA was 0.80 or 0.82, respectively, compared with 0.70 for stage alone (P=0.013 and 0.008, respectively).

CONCLUSIONS

Gene expression and stage combined predict survival of OSCC patients better than stage alone.

Simultaneous isolation of DNA and RNA from the same cell population obtained by laser capture microdissection for genome and transcriptome profiling

Laser capture microdissection (LCM) is used extensively for genome and transcriptome profiling. Traditionally, however, DNA and RNA are purified from separate populations of LCM-harvested cells, limiting the strength of inferences about the relationship between gene expression and gene sequence variation. There have been no published protocols for the simultaneous isolation of DNA and RNA from the same cells that are obtained by LCM of patient tissue specimens. Here we report an adaptation of the Qiagen AllPrep method that allows the purification of DNA and RNA from the same LCM-harvested cells. We compared DNA and RNA purified by the QIAamp DNA Micro kit and the PicoPure RNA Isolation kit, respectively, from LCM-collected cells from adjacent tissue sections of the same specimen. The adapted method yields 90% of DNA and 38% of RNA compared with the individual methods. When tested with the GeneChip 250K Nsp Array, the concordance rate of the single nucleotide polymorphism heterozygosity calls was 98%. When tested with the GeneChip U133 Plus 2.0 Array, the correlation coefficient of the raw gene expression was 97%. Thus, we developed a method to obtain both DNA and RNA material from a single population of LCM-harvested cells and herein discuss the strengths and limitations of this methodology.

The development of a protoplanetary disk from its natal envelope

Class 0 protostars, the youngest type of young stellar objects, show many signs of rapid development from their initial, spheroidal configurations, and therefore are studied intensively for details of the formation of protoplanetary disks within protostellar envelopes. At millimetre wavelengths, kinematic signatures of collapse have been observed in several such protostars, through observations of molecular lines that probe their outer envelopes. It has been suggested that one or more components of the proto-multiple system NGC 1333-IRAS 4 (refs 1, 2) may display signs of an embedded region that is warmer and denser than the bulk of the envelope. Here we report observations that reveal details of the core on Solar System dimensions. We detect in NGC 1333-IRAS 4B a rich emission spectrum of H2O, at wavelengths 20-37 microm, which indicates an origin in extremely dense, warm gas. We can model the emission as infall from a protostellar envelope onto the surface of a deeply embedded, dense disk, and therefore see the development of a protoplanetary disk. This is the only example of mid-infrared water emission from a sample of 30 class 0 objects, perhaps arising from a favourable orientation; alternatively, this may be an early and short-lived stage in the evolution of a protoplanetary disk.

The NASA Spitzer Space Telescope

The National Aeronautics and Space Administration's Spitzer Space Telescope (formerly the Space Infrared Telescope Facility) is the fourth and final facility in the Great Observatories Program, joining Hubble Space Telescope (1990), the Compton Gamma-Ray Observatory (1991-2000), and the Chandra X-Ray Observatory (1999). Spitzer, with a sensitivity that is almost three orders of magnitude greater than that of any previous ground-based and space-based infrared observatory, is expected to revolutionize our understanding of the creation of the universe, the formation and evolution of primitive galaxies, the origin of stars and planets, and the chemical evolution of the universe. This review presents a brief overview of the scientific objectives and history of infrared astronomy. We discuss Spitzer's expected role in infrared astronomy for the new millennium. We describe pertinent details of the design, construction, launch, in-orbit checkout, and operations of the observatory and summarize some science highlights from the first two and a half years of Spitzer operations. More information about Spitzer can be found at http://spitzer.caltech.edu/.

Genetic Factors in Catechol Estrogen Metabolism in Relation to the Risk of Endometrial Cancer

2-Hydroxylated metabolites of estrogen have been shown to have antiangiogenic effects and inhibit tumor cell proliferation, whereas 4-hydroxylated metabolites have been implicated in carcinogenesis. We examined whether polymorphisms in certain genes involved in estrogen metabolism are associated with endometrial cancer risk in a population-based case-control study with 371 cases and 420 controls. Based on previously published genotype-phenotype correlation studies, we defined variant alleles thought to increase estrogen 2-hydroxylation as presumptively low-risk (CYP1A1 m1 T6235C and m2 Ile(462)Val) and those thought to increase estrogen 4-hydroxylation as high-risk (CYP1A1 m4 Thr(461)Asn, CYP1A2 A734C, and CYP1B1 Leu(432)Val). Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using unconditional logistic regression. Carrying at least one CYP1A1 m1 or m2 variant allele was associated with a decreased risk of endometrial cancer [ORs (95% CIs), 0.64 (0.44-0.93) and 0.54 (0.30-0.99), respectively]. No strong alteration in risk was observed among women with any of the putative high-risk alleles. When CYP1A1, CYP1A2, and CYP1B1 genotypes were combined and ranked by the number of putative low-risk genotypes carried, women with four or five low-risk genotypes had a reduced risk of endometrial cancer (OR, 0.29; 95% CI, 0.15-0.56) compared with women with one or none. No appreciable alteration in risk was observed among women carrying two or three low-risk genotypes. Some of our findings are consistent with the hypothesis that increased estrogen 2-hydroxylation is associated with decreased endometrial cancer risk, but replication of these results is required before any firm conclusions can be reached.

Heteroarotinoids inhibit head and neck cancer cell lines in vitro and in vivo through both RAR and RXR retinoic acid receptors

A class of less toxic retinoids, called heteroarotinoids, was evaluated for their molecular mechanism of growth inhibition of two head and neck squamous cell carcinoma (HNSCC) cell lines SCC-2 and SCC-38. A series of 14 heteroarotinoids were screened for growth inhibition activity in vitro. The two most active compounds, one that contained an oxygen heteroatom (6) and the other a sulfur heteroatom (16), were evaluated in a xenograph model of tumor establishment in nude mice. Five days after subcutaneous injection of 10(7) SCC-38 cells, groups of 5 nu/nu mice were gavaged daily (5 days/week for 4 weeks) with 20 mg/kg/day of all-trans-retinoic acid (t-RA, 1), 10 mg/kg/day of 6, 10 mg/kg/day of 16, or sesame oil. After a few days, the dose of t-RA (1) was decreased to 10 mg/kg/day to alleviate the side effects of eczema and bone fracture. No significant toxic effects were observed in the heteroarotinoid groups. All three retinoids caused a statistically significant reduction in tumor size as determined by the Student t-test (P < 0. 05). Complete tumor regression was noted in 3 of 5 mice treated with t-RA (1), 4 of 5 mice treated with 16, 1 of 5 mice treated with 6, and 1 of 5 mice treated with sesame oil. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to determine that the expression levels of RARalpha, RXRalpha, and RXRbeta were similar in the two cell lines, while RARbeta expression was higher in SCC-2 over SCC-38, and RARgamma expression was higher in SCC-38 over SCC-2. Receptor cotransfection assays in CV-1 cells demonstrated that 16 was a potent activator of both RAR and RXR receptors, while 6 was selective for the RXR receptors. Transient cotransfection assays in CV-1 cells using an AP-1 responsive reporter plasmid demonstrated that t-RA (1), 6, and 16 each inhibited AP-1-driven transcription in this cell line. In conclusion, the growth inhibition activity of the RXR-selective 6 and the more potent growth inhibition activity of the RAR/RXR pan-agonist 16 implicate both RARs and RXRs in the molecular mechanism of retinoid growth inhibition. Moreover, the chemoprevention activity and the lack of toxicity of heteroarotinoids demonstrate their clinical potential in head and neck cancer chemoprevention.

Presentation Graphics Using an MS-DOS Computer

Educational objectives: To understand state-of-the-art techniques for producing graphics materials for professional scientific publications and presentations, and to use a popular graphics program to produce graphics materials.

Management of cervical lymph nodes in squamous carcinomas of the head and neck

Due to the overwhelming prognostic significance of regional metastases, proper management of cervical lymph nodes in cases of squamous cell carcinoma of the head and neck is essential for an optimal outcome. Better understanding of the predictability of incidence and patterns of metastases of these tumors in recent years has led us away from the radical neck dissection as the only surgical therapeutic or staging procedure done on the neck. Recent studies suggest that selective removal of lymph node groups at risk in clinically negative necks, or modified neck dissections that save important structures, like the jugular vein, XI nerve, and sternocleidomastoid muscle, in clinically positive necks, are appropriate in many patients. Careful selection of the type of neck dissection and judicious use of postoperative radiation therapy can optimize cure rates as well as functional and cosmetic results.

Accumulation of the p53 tumor-suppressor gene product in oral leukoplakia

OBJECTIVES

(1) To determine whether the protein of the suppressor gene p53 accumulates in leukoplakia of the oral cavity in individuals who use snuff; and (2) to determine whether a correlation exists between the accumulation of p53 protein and the degree of epithelial dysplasia present in oral leukoplakia.

DESIGN

Retrospective analysis of archival tissue specimens.

SETTING

The University Hospital, a tertiary referral hospital affiliated with the Oklahoma University Medical Center, Oklahoma City, Oklahoma.

PATIENTS

In the first part of the study, biopsy specimens of leukoplakia from 12 persons who used snuff were compared with specimens from uninvolved oral mucosa of the same persons and with biopsy specimens from 12 nontobacco-using persons. In the second part of the study, accumulation of p53 protein was determined in 42 archival paraffin-embedded specimens from oral leukoplakia and correlated with the degree of epithelial dysplasia.

METHODS

Accumulation of p53 protein was assessed by immunoperoxidase staining with four different primary antibodies. Positive cells were counted in five consecutive high-power fields.

RESULTS

In part one, the average number of positive cells in the leukoplakia of snuff-users (21.89 +/- 4.33; mean +/- SE) was higher than that of normal-appearing mucosa (4.00 +/- 1.0; p < 0.05) and that of nontobacco-using controls (7.00 +/- 5.04). In part two, the average number of positive cells was higher in the moderately dysplastic (140.36 +/- 30.03) and severely dysplastic lesions (232.86 +/- 26.85) than in the mildly dysplastic lesions (14.53 +/- 3.33; p < 0.05). The correlation between the degree of epithelial dysplasia and the number of cells positive is strong (Spearman's correlation coefficient = 0.853).

CONCLUSIONS

The accumulation of p53 protein in leukoplakia of snuff-users is higher than in normal-appearing oral mucosa from both snuff-users and nontobacco-using controls. A strong correlation exists between the degree of epithelial dysplasia present in oral leukoplakia and the number of cells staining positive for p53. The accumulation of p53 protein holds potential as an intermediate end point in studies of chemoprevention of oral cancer.

Do histocompatibility antigens antigence influence the risk of head and neck carcinoma?

Associations were sought between specific histocompatibility antigens (HLA) of the human major histocompatibility complex and the incidence of head and neck squamous cell carcinoma (SqCC). Seventy sequential patients with SqCC and 217 control subjects from the same geographic region were typed for HLA-A, HLA-B, and HLA-DR loci. These results were compared. Multivariate statistical analysis using stepwise logistic regression revealed significant associations between the incidence of SqCC and HLA-B14, HLA-DR3, and HLA-DR4 as well as smoking and the sex-smoking interaction. The authors concluded that certain host factors, including genetic constitution, and behavioral characteristics (i.e., smoking) as well as tumor biology, can influence the development of SqCC. The mechanism(s) of these associations may involve as yet undefined relationships between HLA region genes and the immune response.

Sudden bilateral profound hearing loss resulting from meningeal carcinomatosis

SBPHL is a rare manifestation of hearing loss. Patients with SBPHL should have a thorough evaluation for meningeal carcinomatosis as the cause, including a complete neurologic evaluation, CT scan, and, probably, MRI. If MC is highly suspected, an LP is necessary. Because the diagnosis of MC can be confirmed only by the presence of malignant cells in the CSF, multiple LPs may be necessary to find them. Although MC should be strongly considered in the differential diagnosis of SBPHL, MC should also be considered with other patterns of eighth cranial nerve involvement, especially in patients with a history of malignancy. These patterns include unilateral hearing loss associated with tinnitus, unilateral hearing loss rapidly progressing to severe bilateral involvement, audiologic and caloric studies that show eighth cranial nerve impairment, and facial nerve palsy associated with hearing loss. The prognosis for MC is poor, although intraventricular chemotherapy and whole brain radiotherapy can provide significant palliation.

HLA class I and class II antigen expression on squamous cell carcinoma of the head and neck

We compared human major histocompatibility (HLA) class I and class II antigen expression on squamous cell carcinoma of the head and neck with that on normal mucosa. Frozen sections of a consecutive series of 30 squamous cell carcinomas were stained with the monoclonal antibodies W6/32 (class I) and anti-DR (class II) using an immunoperoxidase technique. Normal mucosa showed class I and class II expression in the basal layers only. Class I expression on tumors was diffuse in 87%, patchy in 10%, and scattered in 3%. Class II expression on tumors was diffuse in 20%, patchy in 53%, scattered in 20%, and absent in 7%. Patterns of expression did not correlate significantly with clinical parameters, including survival, except that class II diffuse and patchy patterns were found to correlate with more poorly differentiated tumors.

Advanced head and neck cancer: low-dose, split-course radiation therapy and simultaneous infusion of 5-fluorouracil and cisplatin

Twenty-three patients with advanced untreated head and neck cancer, nine patients with recurrent cancer, and six patients with recurrent cancer who underwent surgery and had postoperative persistence of tumor were treated with three 2-week courses of irradiation (1,500 cGy in 10 fractions each) concurrently with cisplatin and a 5-day infusion of 5-fluorouracil. A fourth 2-week course of irradiation (2,000 cGy in 10 fractions) brought the final tumor dose to 6,500 cGy. Twenty patients in the untreated group and three patients in the recurrent group (33%) had a complete response. There were 10 local recurrences in the untreated group (43%), seven in the recurrent group (78%), and three in the persistent group (50%). At 17 months after the start of treatment, the survival rate for the untreated patients was 51%, for the patients in the recurrent group it was 11%, and for the patients in the persistent group it was 20% (P = .03). Most patients experienced toxicity, including nausea, vomiting, weight loss, and mucositis. Clinical trials are necessary to determine whether simultaneous chemotherapy and radiation therapy is an improved method of treatment for advanced head and neck cancer.

Suction-assisted lipectomy in the management of obstructive sleep apnea

Suction-assisted lipectomy is a valuable method of aesthetic recontouring of the neck. We report the successful use of suction-assisted lipectomy as an adjunctive procedure at the time of tracheostomy in the treatment of obese patients with severe obstructive sleep apnea. This functional procedure helps to maintain tracheostomy patency during sleep.

Effect of helium concentration on experimental upper airway obstruction

This study investigates the effect of helium concentration in inspired gas on resistance to breathing during experimental upper airway obstruction. Obstruction was modeled by use of a series of four polyvinyl endotracheal tubes narrowed progressively in their midportions with C clamps. Percentage ratios of helium-oxygen gas mixtures were 0:100, 40:60, 60:40, and 80:20. Gas flow was provided by two methods: 1) nontidal flow from compressed gas tanks from which resistance was calculated from pressure and flow measurements, and 2) tidal respiratory flow from human volunteers from whom respiratory effort was evaluated by using airway pressure measurements integrated over 90-second trial periods. The results derived from both methods demonstrated that the effect of helium in reducing resistance and pressure in an obstructed airway is linear (p less than .016) and inversely proportional to helium concentration. Reductions in resistance and pressure were larger for the tighter obstructions (p less than .007). As helium was added to the gas mixture (from 0% to 80%), resistance and airway pressure measurements dropped 42% and 58%, respectively. The major conclusions are that 1) even low concentrations of helium may have therapeutic value and 2) helium is effective only for more severe obstructions.

The tooth as a foreign body in soft tissue after head and neck trauma

Thorough evaluation of dentition is important in the management of craniofacial trauma. Avulsed or fractured teeth in the pulmonary and gastrointestinal tracts can lead to serious complications that are well described. However, the penetration of avulsed teeth into soft tissues of the head and neck is unusual and may not be recognized. Two cases in which a tooth became a foreign body in these soft tissues are illustrative. One patient had bronchoscopy for possible aspiration of an avulsed maxillary canine; it was later found embedded in the premaxillary tissues. The other patient had a right mandibular molar propelled into the posterior triangle of the left side of the neck. Physicians must be aware of dental injury resulting from facial trauma and account for all teeth as part of their evaluation, keeping an open mind as to where a missing tooth might be located.

Modulation of human leukocyte antigen class I expression by gamma interferon in head and neck cancer cell lines

One possible mechanism explaining the action of interferon (IFN) on squamous cell carcinoma (SqCC) of the head and neck is the modulation of major histocompatibility antigen expression on tumor cells. We tested the ability of gamma interferon (gamma-IFN) to modulate major histocompatibility class I antigens and beta 2-microglobulin (beta 2-M) on two carcinoma cell lines derived from SqCC of the head and neck. Major histocompatibility class I antigens and beta 2-M were detected using a two-step immunochemical stain; antigen expression was quantified using flow cytometry. gamma-IFN increased constitutive antigen expression by as much as five times on both cell lines. Maximum modulation was seen within 72 hours of exposure to gamma-IFN at clinically attainable doses (10 U/mL to 100 U/mL). The presence of gamma-IFN in cell cultures was necessary for continued modulation of surface antigens. These findings suggest a possible mechanism of action and encourage further clinical trials with gamma-IFN.

Epistaxis: medical versus surgical therapy: a comparison of efficacy, complications, and economic considerations

A retrospective review of 4 years experience with over 32 epistaxis patients requiring hospitalization and using a standard medical or surgical therapy for control is presented. Medical therapy included the use of anterior nasal packing alone or in association with intranasal and nasopharyngeal balloon tamponade. Surgical therapy, for the most part, consisted of ethmoid and/or internal maxillary artery ligations. Most patients were treated initially with packing and balloons. Fifty-two percent of the group failed this therapy and required ligations for control. The patients who did not come to operation had fewer complications, a shorter average hospital stay, and lower average cost of hospitalization without increased risk of future epistaxis. An analysis is made comparing the results, complications, and financial implications of these two approaches.

Further clinical experience with the silicone tracheal cannula in obstructive sleep apnea

We report on the perioperative and postoperative course of 47 patients with severe obstructive sleep apnea, who underwent tracheostomy by use of a silicone tracheal cannula developed by Dr. William Montgomery. Our initial experience with the first 20 of these patients (presented in 1982) was quite favorable because of the ease of insertion and care, a high degree of patient acceptance, and infrequent complications. With our current sample, larger experience, and more prolonged follow-up, we noted that symptomatic granulation tissue formation, with or without wound infection, occurred more frequently than was initially appreciated. In 21% (10 of 47) of the cases, the only way to resolve this problem was to remove this device and replace it permanently with a metal (or other type) tracheostomy tube. Other complications included tracheal narrowing and cannula malpositioning and fragmentation. This full report lists in detail the incidence of complications associated with our use of this cannula and modifications which may lessen these.

Infrared Astronomy After IRAS

The 250,000 sources in the recently issued Infrared Astronomy Satellite (IRAS) all-sky infrared catalog are a challenge to astronomy. Many of these sources will be studied with existing and planned ground-based and airborne telescopes, but many others can no longer even be detected now that IRAS has ceased to operate. As anticipated by advisory panels of the National Academy of Sciences for a decade, study of the IRAS sources will require the Space Infrared Telescope Facility (SIRTF), a cooled, pointed telescope in space. This instrument may be the key to our understanding of cosmic birth-the formation of planets, stars, galaxies, active galactic nuclei, and quasars. Compared with IRAS and existing telescopes, SIRTF's power derives from a thousandfold gain in sensitivity over five octaves of the spectrum.

Early Results from the Infrared Astronomical Satellite

For 10 months the Infrared Astronomical Satellite (IRAS) provided astronomers with what might be termed their first view of the infrared sky on a clear, dark night. Without IRAS, atmospheric absorption and the thermal emission from both the atmosphere and Earthbound telescopes make the task of the infrared astronomer comparable to what an optical astronomer would face if required to work only on cloudy afternoons. IRAS observations are serving astronomers in the same manner as the photographic plates of the Palomar Observatory Sky Survey; just as the optical survey has been used by all astronomers for over three decades, as a source of quantitative information about the sky and as a "roadmap" for future observations, the results of IRAS will be studied for years to come. IRAS has demonstrated the power of infrared astronomy from space. Already, from a brief look at a miniscule fraction of the data available, we have learned much about the solar system, about nearby stars, about the Galaxy as a whole and about distant extragalactic systems. Comets are much dustier than previously thought. Solid particles, presumably the remnants of the star-formation process, orbit around Vega and other stars and may provide the raw material for planetary systems. Emission from cool interstellar material has been traced throughout the Galaxy all the way to the galactic poles. Both the clumpiness and breadth of the distribution of this material were previously unsuspected. The far-infrared sky away from the galactic plane has been found to be dominated by spiral galaxies, some of which emit more than 50 percent and as much as 98 percent of their energy in the infrared-an exciting and surprising revelation. The IRAS mission is clearly the pathfinder for future missions that, to a large extent, will be devoted to the discoveries revealed by IRAS.

Immunomodulatory activity in regional lymph nodes

This study is, to our knowledge, the first attempt to evaluate cellular immune mechanisms in regional lymph nodes of patients with head and neck cancer. Twenty lymph nodes from eight patients with stage III-IV squamous cell carcinoma were evaluated using an in vitro culture system. The T-cell mitogenic (concanavalin A) response of patients' peripheral blood mononuclear cells was modulated by the addition of cells from regional lymph nodes removed at neck dissection. Modulatory activity showing augmentation was significantly correlated with the size of the primary tumor and histopathologic grade of the tumor. Modulatory activity did not correlate with the histologic pattern of lymph node reactivity. Although these relationships suggest that regional immunity may be important in tumor-host interactions, further study is necessary to establish their biologic and prognostic importance.

Jupiter: Its Infrared Spectrum from 16 to 40 Micrometers

Spectral measurements of the thermal radiation from Jupiter in the band from 16 to 40 micrometers are analyzed under the assumption that pressure-broadened molecular hydrogen transitions are responsible for the bulk of the infrared opacity over most of this spectral interval. Both the vertical pressure-temperature profile and the molecular hydrogen mixing ratio are determined. The derived value ofthe molecular hydrogen mixing ratio, 0.89 +/- 0.11, is consistent with the solar value of 0.86.

Black paints for far infrared cryogenic use

A cryogenic paint which remains absorptive throughout the infrared has been developed. The paint exhibits excellent surface stability at liquid helium temperature and is resistant to abrasion and flaking. Measurements in a specially constructed cryogenic integrating sphere indicate that the paint is ~92-100% absorptive in the 70-130-micro range. Additional broadband measurements at 60 micro-130 micro, 18 micro-25micro, and 400 micro-1 mm indicate that the paint is ~95% absorptive.

Far-Infrared Observations of the Night Sky

We have flown a telescope cooled to liquid-helium temperatures and made far-infrared observations of the night sky. A gallium-doped germanium detector, sensitive from 5.2 to 130 micrometers, detected a minimum signal of 10(-9) watt per square centimeter per steradian referred to 100 micrometers. The origin of this signal can be instrumental, atmospheric, interplanetary, or interstellar. We can place a firm upper limit on the color temperature of a dilute cosmic background flux.

Rocket-borne liquid helium cooled telescope

We describe a rocket-borne telescope in which all components in or near the detector's field of view are cooled to liquid helium temperature. The system uses ir detectors to make photometric observations of the night sky in the 5-mu to ~1.6 mm spectral range. A description of the detectors and their calibration is given. On 29 February 1968, the telescope was successfully flown to an altitude of 170 km on an Aerobee 150 sounding rocket.