Stereotactic body radiotherapy as primary treatment for elderly patients with medically-inoperable head-and-neck cancer

Purpose: With a growing elderly population, elderly patients with head-and-neck cancers represent an increasing challenge with limited prospective data to guide management. The complex interplay between advanced age, associated comorbidities, and conventional local therapies such as surgery and external beam radiotherapy ± chemotherapy, can significantly impact elderly patients' quality-of-life (QOL). SBRT is a well-established curative strategy for medicalinoperable. early-stage lung cancers even in elderly populations; however there is limited data examining SBRT as primary therapy in head-and-neck cancer. Material/Methods: Twelve patients with medically-inoperable head-and-neck cancer treated with SBRT ± cetuximab from 2002 through 2013 were retrospectively reviewed. SBRT consisted of primarily 44Gy in 5 fractions delivered on alternating days over 1-2 weeks. Concurrent cetuximab was administer at a dose of 400mg/m2 on day -7 followed by 250mg/m2 on day 0 and +7 in n=3 (25%). Patient reported quality-of-life (PRQoL) was prospectively recorded using the previously-validated University-of-Washington Quality-of-Life Revised (UW-QoL-R). Results: Median clinical follow-up was 6-months (range: 0.5 - 29 months). The 1-year actuarial local progression-free survival, distant progression-free survival,progression-free survival, and overall survival for definitively treated patients were 69%, 100%, 69% and 64%, respectively. One patient (8%) experienced acute grade 3 dysphagia and one patient (8%) experienced late grade 3 mucositis; there were no grade 4-5 toxicities. Prospective collection of patient report quality-of-life as assessed by UW-QoL-R was preserved across domains. Conclusion: SBRT shows encouraging survival and relatively low toxicity in elderly patients with unresectable head-and-neck cancer; which may provide an aggressive potentially curative local therapy while maintaining quality-of-life. © 2014 Vargo, Ferris, Clump and Heron

Regulation of HPV16 E6 and MCL1 by SF3B1 inhibitor in head and neck cancer cells

ABT-737 inhibits the anti-apoptotic proteins B-cell lymphoma 2 (BCL-2) and BCL-X L. Meayamycin B switches the splicing pattern of myeloid cell leukemia factor 1 (MCL1) pre-mRNA. Specifically, inhibition of splicing factor 3B subunit 1 (SF3B1) with meayamycin B promotes the generation of the proapoptotic, short splicing variant (MCL1-S) and diminishes the antiapoptotic, long variant (MCL1-L). This action was previously associated with the cytotoxicity of meayamycin B in non-small cell lung carcinoma cell lines. ABT-737 induced apoptosis in response to an ablation of MCL1-L by meayamycin B. In this study, we further exploited this synergistic combination in head and neck squamous cell carcinoma (HNSCC), up to 90% of which overexpress MCL1 and BCL-X L. In a panel of seven HNSCC cell lines, the combination of meayamycin B and ABT-737 rapidly triggered a Bax/Bak-mediated apoptosis that overcame the resistance from HPV16-positive HNSCC against each agent alone. Both RT-PCR and Western blotting showed that meayamycin B up-regulated MCL1-S and down-regulated MCL1-L. Significantly, we discovered that SF3B1 was involved in the splicing of oncogenic HPV16 E6 to produce non-oncogenic HPV16 E6*, indicating that SF3B1 may inhibit HPV16-induced tumorigenesis

Cetuximab ameliorates suppressive phenotypes of myeloid antigen presenting cells in head and neck cancer patients

Background: Myeloid-derived suppressor cells (MDSC) and M2 monocytes/macrophages are two types of suppressive myeloid antigen presenting cells that have been shown to promote tumor progression and correlate with poor prognosis in cancer patients. Tumor antigen specific monoclonal antibodies (mAb) have emerged as important agents for cancer therapy. In addition to the direct inhibition of tumor growth, the Fc portions of the therapeutic mAbs, such as the IgG1 portion of the anti-epidermal growth factor receptor (EGFR) mAb cetuximab, might interact with the Fc-gamma receptors (FcγR) on myeloid cells and modulate their suppressive activity. Methods: Patients with locally advanced head and neck squamous cell carcinoma (HNSCC) on the UPCI 08-013 NCT01218048 trial were treated with single-agent cetuximab before surgery. Blood were collected pre- and post-cetuximab treatment to analyze frequency of monocytic MDSC (CD11b+CD14+HLA-DRlo/-), granulocytic MDSC (LIN-CD11b+CD15+) and CD11b+CD14+HLA-DRhi monocytes by flow cytometry. Besides, CD11b+CD14+HLA-DRhi monocytes were sorted for qPCR analysis of IL-10 and IL-12B transcripts. MDSC were generated in vitro with or without coated hIgG1 and tested for suppressive activity in mixed leukocyte reaction (MLR). Naïve monocytes from HNSCC patients co-cultured with tumor cell lines in the presence of cetuximab or hIgG1 were analyzed for M1/2 surface markers and cytokines. Results: We observed significantly increased monocytic MDSC in non-responders and decreased granulocytic MDSC in responders after cetuximab treatment. In addition, circulating CD11b+CD14+HLA-DRhi monocytes of cetuximab responders displayed attenuated M2 polarization, with decreased CD163+ expression and IL-10 transcripts after cetuximab treatment. This beneficial effect appeared to be FcγR dependent, since CD16 ligation reproduced the reversal of suppressive activity of MDSC in vitro. CD14+ naïve monocytes from the co-cultures of tumor cells, cetuximab and HNSCC patient PBMC or purified monocytes were skewed to an M1-like phenotype, with increased expression of HLA-DR, CD86 and production of IL-12 p70. Likewise, reduced M2 features (expression of CD163 and production of IL-10) were found after crosslinking CD16 on the surface of monocytes to cetuximab-coated tumor cells. Conclusion: Our studies demonstrate a novel function of cetuximab in ameliorating suppressive phenotypes of FcγR bearing myeloid cells in cancer patients, which is associated with better clinical outcome of cetuximab-treated patients. Clinical trial registry: # NCT01218048. Registered 7 October 2010

Quantifying metabolic heterogeneity in head and neck tumors in real time: 2-DG uptake is highest in hypoxic tumor regions

Purpose: Intratumoral metabolic heterogeneity may increase the likelihood of treatment failure due to the presence of a subset of resistant tumor cells. Using a head and neck squamous cell carcinoma (HNSCC) xenograft model and a real-time fluorescence imaging approach, we tested the hypothesis that tumors are metabolically heterogeneous, and that tumor hypoxia alters patterns of glucose uptake within the tumor. Experimental Design: Cal33 cells were grown as xenograft tumors (n = 16) in nude mice after identification of this cell line's metabolic response to hypoxia. Tumor uptake of fluorescent markers identifying hypoxia, glucose import, or vascularity was imaged simultaneously using fluorescent molecular tomography. The variability of intratumoral 2-deoxyglucose (IR800-2-DG) concentration was used to assess tumor metabolic heterogeneity, which was further investigated using immunohistochemistry for expression of key metabolic enzymes. HNSCC tumors in patients were assessed for intratumoral variability of 18F-fluorodeoxyglucose (18F-FDG) uptake in clinical PET scans. Results: IR800-2-DG uptake in hypoxic regions of Cal33 tumors was 2.04 times higher compared to the whole tumor (p = 0.0001). IR800-2-DG uptake in tumors containing hypoxic regions was more heterogeneous as compared to tumors lacking a hypoxic signal. Immunohistochemistry staining for HIF-1α, carbonic anhydrase 9, and ATP synthase subunit 5β confirmed xenograft metabolic heterogeneity. We detected heterogeneous 18F-FDG uptake within patient HNSCC tumors, and the degree of heterogeneity varied amongst tumors. Conclusion: Hypoxia is associated with increased intratumoral metabolic heterogeneity. 18F-FDG PET scans may be used to stratify patients according to the metabolic heterogeneity within their tumors, which could be an indicator of prognosis. © 2014 Nakajima et al

PET-CT staging of the neck in cancers of the oropharynx: patterns of regional and retropharyngeal nodal metastasis

Objective: To study the retropharyngeal lymph node status (RPLN) by pretreatment PET-CT imaging in patients with squamous cell carcinomas of the oropharynx (OPSCC). Study Design: Retrospective.Methods: 101 patients with a biopsy proven OPSCC were identified. 53 patients meeting inclusion criteria were further analyzed.Results: The frequency of RPLN was 20.8% (11/53). Advanced T stage cancer (OR = 5.6250, 95% CI: 1.06 - 29.80, p = 0.0410) and advanced clinical N stage cancer (i.e. N2+) had higher odds (OR = 3.9773, 95% CI: 0.9628 - 16.4291) of being RPLN positive as compared to N0-1 patients.Conclusions: Pre-treatment PET-CT can be used as a staging tool to aid in treatment planning of OPSCC, as rates of RPLN and nodal metastasis are consistent with those reported in the literature. Advanced T and N stage are associated with a greater odds ratio of being RPLN positive by PET-CT imaging. © 2010 Tauzin et al; licensee BioMed Central Ltd

Society for immunotherapy of cancer (SITC) statement on the proposed changes to the common rule

The Common Rule is a set of ethical principles that provide guidance on the management of human subjects taking part in biomedical and behavioral research in the United States. The elements of the Common Rule were initially developed in 1981 following a revision of the Declaration of Helsinki in 1975. Most academic facilities follow the Common Rule in the regulation of clinical trials research. Recently, the government has suggested a revision of the Common Rule to include more contemporary and streamlined oversight of clinical research. In this commentary, the leadership of the Society for Immunotherapy of Cancer (SITC) provides their opinion on this plan. While the Society recognizes the considerable contribution of clinical research in supporting progress in tumor immunotherapy and supports the need for revisions to the Common Rule, there is also some concern over certain elements which may restrict access to biospecimens and clinical data at a time when high throughput technologies, computational biology and assay standardization is allowing major advances in understanding cancer biology and providing potential predictive biomarkers of immunotherapy response. The Society values its professional commitment to patients for improving clinical outcomes with tumor immunotherapy and supports continued discussion with all stakeholders before implementing changes to the Common Rule in order to ensure maximal patient protections while promoting continued clinical research at this historic time in cancer research

MicroRNA-363 targets myosin 1B to reduce cellular migration in head and neck cancer

Background: Squamous cell carcinoma of the head and neck (SCCHN) remains a prevalent and devastating disease. Recently, there has been an increase in SCCHN cases that are associated with high-risk human papillomavirus (HPV) infection. The clinical characteristics of HPV-positive and HPV-negative SCCHN are known to be different but their molecular features are only recently beginning to emerge. MicroRNAs (miRNAs, miRs) are small, non-coding RNAs that are likely to play significant roles in cancer initiation and progression where they may act as oncogenes or tumor suppressors. Previous studies in our laboratory showed that miR-363 is overexpressed in HPV-positive compared to HPV-negative SCCHN cell lines, and the HPV type 16-E6 oncoprotein upregulates miR-363 in SCCHN cell lines. However, the functional role of miR-363 in SCCHN in the context of HPV infection remains to be elucidated. Methods: We analyzed miR-363 levels in SCCHN tumors with known HPV-status from The Cancer Genome Atlas (TCGA) and an independent cohort from our institution. Cell migration studies were conducted following the overexpression of miR-363 in HPV-negative cell lines. Bioinformatic tools and a luciferase reporter assay were utilized to confirm that miR-363 targets the 3'-UTR of myosin 1B (MYO1B). MYO1B mRNA and protein expression levels were evaluated following miR-363 overexpression in HPV-negative SCCHN cell lines. Small interfering RNA (siRNA) knockdown of MYO1B was performed to assess the phenotypic implication of reduced MYO1B expression in SCCHN cell lines. Results: MiR-363 was found to be overexpressed in HPV-16-positive compared to the HPV-negative SCCHN tumors. Luciferase reporter assays performed in HPV-negative JHU028 cells confirmed that miR-363 targets one of its two potential binding sites in the 3'UTR of MYO1B. MYO1B mRNA and protein levels were reduced upon miR-363 overexpression in four HPV-negative SCCHN cell lines. Increased miR-363 expression or siRNA knockdown of MYO1B expression reduced Transwell migration of SCCHN cell lines, indicating that the miR-363-induced migration attenuation of SCCHN cells may act through MYO1B downregulation. Conclusions: These findings demonstrate that the overexpression of miR-363 reduces cellular migration in head and neck cancer and reveal the biological relationship between miR-363, myosin 1b, and HPV-positive SCCHN

A retrospective, deformable registration analysis of the impact of PET-CT planning on patterns of failure in stereotactic body radiation therapy for recurrent head and neck cancer

Background: Stereotactic body radiation therapy (SBRT) has seen increasing use as a salvage strategy for selected patients with recurrent, previously-irradiated squamous cell carcinoma of the head and neck (rSCCHN). PET-CT may be advantageous for tumor delineation and evaluation of treatment failures in SBRT. We analyzed the patterns of failure following SBRT for rSCCHN and assessed the impact of PET-CT treatment planning on these patterns of failure. Methods: We retrospectively reviewed 96 patients with rSCCHN treated with SBRT. Seven patients (7%) were treated after surgical resection of rSCCHN and 89 patients (93%) were treated definitively. PET-CT treatment planning was used for 45 patients whereas non-PET-CT planning was used for 51 patients. Categories of failure were assigned by comparing recurrences on post-treatment scans to the planning target volume (PTV) from planning scans using the deformable registration function of VelocityAI™. Failures were defined: In-field (>75% inside PTV), Overlap (20-75% inside PTV), Marginal (<20% inside PTV but closest edge within 1cm of PTV), or Regional/Distant (more than 1cm from PTV). Results: Median follow-up was 7.4 months (range, 2.652 months). Of 96 patients, 47 (49%) developed post-SBRT failure. Failure distribution was: In-field12.3%, Overlap24.6%, Marginal36.8%, Regional/Distant26.3%. There was a significant improvement in overall failure-free survival (log rank p = 0.037) and combined Overlap/Marginal failure-free survival (log rank p = 0.037) for those receiving PET-CT planning vs. non-PET-CT planning in the overall cohort (n = 96). Analysis of the definitive SBRT subgroup (n = 89) increased the significance of these findings (overall failure: p = 0.008, Overlap/Marginal failure: p = 0.009). There were no significant differences in age, gender, time from prior radiation, dose, use of cetuximab with SBRT, tumor differentiation, and tumor volume between the PET-CT and non-PET-CT groups. Conclusions: Most failures after SBRT treatment for rSCCHN were near misses, i.e. Overlap/Marginal failures (61.4%), suggesting an opportunity to improve outcomes with more sensitive imaging. PET-CT treatment planning showed the lowest rate of overall and near miss failures and is beneficial for SBRT treatment planning. © 2012 Wang et al.; licensee BioMed Central Ltd