Mercedes Porosnicu

Interferon Beta and Interferon Alpha 2a Differentially Protect Head and Neck Cancer Cells from Vesicular Stomatitis Virus-Induced Oncolysis

ABSTRACT Oncolytic viruses (OV) preferentially kill cancer cells due in part to defects in their antiviral responses upon exposure to type I interferons (IFNs). However, IFN responsiveness of some tumor cells confers resistance to OV treatment. The human type I IFNs include one IFN-β and multiple IFN-α subtypes that share the same receptor but are capable of differentially inducing biological responses. The role of individual IFN subtypes in promoting tumor cell resistance to OV is addressed here. Two human IFNs which have been produced for clinical use, IFN-α2a and IFN-β, were compared for activity in protecting human head and neck squamous cell carcinoma (HNSCC) lines from oncolysis by vesicular stomatitis virus (VSV). Susceptibility of HNSCC lines to killing by VSV varied. VSV infection induced increased production of IFN-β in resistant HNSCC cells. When added exogenously, IFN-β was significantly more effective at protecting HNSCC cells from VSV oncolysis than was IFN-α2a. In contrast, normal keratinocytes and endothelial cells were protected equivalently by both IFN subtypes. Differential responsiveness of tumor cells to IFN-α and -β was further supported by the finding that autocrine IFN-β but not IFN-α promoted survival of HNSCC cells during persistent VSV infection. Therefore, IFN-α and -β differentially affect VSV oncolysis, justifying the evaluation and comparison of IFN subtypes for use in combination with VSV therapy. Pairing VSV with IFN-α2a may enhance selectivity of oncolytic VSV therapy for HNSCC by inhibiting VSV replication in normal cells without a corresponding inhibition in cancer cells. IMPORTANCE There has been a great deal of progress in the development of oncolytic viruses. However, a major problem is that individual cancers vary in their sensitivity to oncolytic viruses. In many cases this is due to differences in their production and response to interferons (IFNs). The experiments described here compared the responses of head and neck squamous cell carcinoma cell lines to two IFN subtypes, IFN-α2a and IFN-β, in protection from oncolytic vesicular stomatitis virus. We found that IFN-α2a was significantly less protective for cancer cells than was IFN-β, whereas normal cells were equivalently protected by both IFNs. These results suggest that from a therapeutic standpoint, selectivity for cancer versus normal cells may be enhanced by pairing VSV with IFN-α2a.

Retrospective analysis of the impact of HPV status and smoking on mucositis in patients with oropharyngeal squamous cell carcinoma treated with concurrent chemotherapy and radiotherapy

OBJECTIVES The standard concurrent radiotherapy and chemotherapy regimens for patients with oropharyngeal cancer are highly toxic. Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) has recently emerged as a distinct biological and clinical entity with improved response to treatment and prognosis. A tailored therapeutic approach is needed to optimize patient care. The aim of our study was to investigate the impact of HPV and smoking status on early toxicities (primarily mucositis) associated with concurrent chemotherapy and radiotherapy in patients with OPSCC. MATERIALS AND METHODS We retrospectively evaluated 72 consecutive patients with OPSCC and known HPV status treated with concurrent radiotherapy and chemotherapy at our institution. Treatment-related toxicities were stratified by smoking and HPV status and compared using univariate and multivariate logistic regression. RESULTS HPV-positive patients had a 6.86-fold increase in the risk of having severe, grade 3-4 mucositis. This effect was preserved after adjusting for patient smoking status, nodal stage, radiotherapy technique and radiotherapy maximum dose. Additionally, HPV status had significant effect on the objective weight loss during treatment and at three months after treatment. Consistently, non-smokers had a significant 2.70-fold increase in the risk of developing severe mucositis. CONCLUSION Risk factors for OPSCC modify the incidence of treatment-related early toxicities, with HPV-positive and non-smoking status correlating with increased risk of high grade mucositis and associated outcomes. Retrospective single-institution studies need to be interpreted cautiously. However, this finding is important to consider when designing therapeutic strategies for HPV-positive patients and merits further investigation in prospective clinical trials.

Retrospective Analysis of Cisplatin Nephrotoxicity in Patients With Head and Neck Cancer Receiving Outpatient Treatment With Concurrent High-dose Cisplatin and Radiotherapy.

Objectives: Cisplatin remains the pivotal chemotherapy in squamous cell carcinoma of the head and neck (SCCHN), with nephrotoxicity considered the dose-limiting toxicity. The purpose of our study was to propose an outpatient high-dose cisplatin protocol aimed at preventing nephrotoxicity and to analyze the results of its utilization in patients with SCCHN treated with concurrent radiotherapy. Materials and Methods: We retrospectively evaluated 82 SCCHN patients treated with outpatient high-dose cisplatin concurrent with radiotherapy at our institution. Acute kidney injury (AKI) and chronic kidney disease were defined by Kidney Disease Improving Global Outcomes criteria. Associated factors were identified using analysis of covariance models for categorical variables and adjusted Pearson correlations for continuous variables. Results: The incidence of AKI during treatment was 34.2%. With a median follow-up of 25.7 months, the average decrease in estimated glomerular filtration rate was 12.57 mL/min/1.73 m2 (SD=18.58). At 1 year and at last follow-up, 5.4% and 4.4% of patients had estimated glomerular filtration rate <60 mL/min/1.73 m2. Predictors associated with AKI and chronic kidney disease were: lower baseline weight and creatinine, higher baseline creatinine clearance, smoking, female sex, African American race, hypertension, and increased hydration and magnesium replacement requirements. Conclusions: We encountered limited early and late nephrotoxicity. Importantly, nephrotoxicity was not the main dose-limiting toxicity. Our results emphasize the importance of close monitoring and additional replacement of water and electrolytes as needed. A consistent method of measuring and reporting chemotherapy-induced nephrotoxicity would be a valuable contribution to the literature.

Circulating mutational portrait of cancer : manifestation of aggressive clonal events in both early and late stages

BackgroundSolid tumors residing in tissues and organs leave footprints in circulation through circulating tumor cells (CTCs) and circulating tumor DNAs (ctDNA). Characterization of the ctDNA portraits and comparison with tumor DNA mutational portraits may reveal clinically actionable information on solid tumors that is traditionally achieved through more invasive approaches.MethodsWe isolated ctDNAs from plasma of patients of 103 lung cancer and 74 other solid tumors of different tissue origins. Deep sequencing using the Guardant360 test was performed to identify mutations in 73 clinically actionable genes, and the results were associated with clinical characteristics of the patient. The mutation profiles of 37 lung cancer cases with paired ctDNA and tumor genomic DNA sequencing were used to evaluate clonal representation of tumor in circulation. Five lung cancer cases with longitudinal ctDNA sampling were monitored for cancer progression or response to treatments.ResultsMutations in TP53, EGFR, and KRAS genes are most prevalent in our cohort. Mutation rates of ctDNA are similar in early (I and II) and late stage (III and IV) cancers. Mutation in DNA repair genes BRCA1, BRCA2, and ATM are found in 18.1% (32/177) of cases. Patients with higher mutation rates had significantly higher mortality rates. Lung cancer of never smokers exhibited significantly higher ctDNA mutation rates as well as higher EGFR and ERBB2 mutations than ever smokers. Comparative analysis of ctDNA and tumor DNA mutation data from the same patients showed that key driver mutations could be detected in plasma even when they were present at a minor clonal population in the tumor. Mutations of key genes found in the tumor tissue could remain in circulation even after frontline radiotherapy and chemotherapy suggesting these mutations represented resistance mechanisms. Longitudinal sampling of five lung cancer cases showed distinct changes in ctDNA mutation portraits that are consistent with cancer progression or response to EGFR drug treatment.ConclusionsThis study demonstrates that ctDNA mutation rates in the key tumor-associated genes are clinical parameters relevant to smoking status and mortality. Mutations in ctDNA may serve as an early detection tool for cancer. This study quantitatively confirms the hypothesis that ctDNAs in circulation is the result of dissemination of aggressive tumor clones and survival of resistant clones. This study supports the use of ctDNA profiling as a less-invasive approach to monitor cancer progression and selection of appropriate drugs during cancer evolution.

Reirradiation for second primary or recurrent cancers of the head and neck: Dosimetric and outcome analysis

The purpose of this study was to examine outcomes, toxicity, and dosimetric characteristics of patients treated with reirradiation for head and neck cancers.

Relation of Pre-anthracycline Serum Bilirubin Levels to Left Ventricular Ejection Fraction After Chemotherapy.

Myocardial injury because of oxidative stress manifesting through reductions in left ventricular ejection fraction (LVEF) may occur after the administration of anthracycline-based chemotherapy (A-bC). We hypothesized that bilirubin, an effective endogenous antioxidant, may attenuate the reduction in LVEF that sometimes occurs after receipt of A-bC. We identified 751 consecutively treated patients with cancer who underwent a pre-A-bC LVEF measurement, exhibited a serum total bilirubin level <2 mg/dl, and then received a post-A-bC LVEF assessment because of symptomatology associated with heart failure. Analysis of variance, Tukeys Studentized range test, and chi-square tests were used to evaluate an association between bilirubin and LVEF changes. The LVEF decreased by 10.7 ± 13.7%, 8.9 ± 11.8%, and 7.7 ± 11.5% in group 1 (bilirubin at baseline ≤0.5 mg/dl), group 2 (bilirubin 0.6 to 0.8 mg/dl), and group 3 (bilirubin 0.9 to 1.9 mg/dl), respectively. More group 1 patients experienced >15% decrease in LVEF compared with those in group 3 (p = 0.039). After adjusting for age, coronary artery disease/myocardial infarction, diabetes mellitus, hematocrit, and the use of cardioactive medications, higher precancer treatment bilirubin levels and lesser total anthracycline doses were associated with LVEF preservation (p = 0.047 and 0.011, respectively). In patients treated with anthracyclines who subsequently develop symptoms associated with heart failure, pre-anthracycline treatment serum bilirubin levels inversely correlate with subsequent deterioration in post-cancer treatment LVEF. In conclusion, these results suggest that increased levels of circulating serum total bilirubin, an intrinsic antioxidant, may facilitate preservation of LVEF in patients receiving A-bC for cancer.

Urinary Specific Gravity (USG) as an Assessment Tool for the Management of Dehydration in Head and Neck Cancer Patients Receiving Chemo-Radiation with Weekly Cisplatin

Background: Concomitant chemo-radiation therapy (CRT) with cisplatin is the mainstay of treatment for patients with locally advanced head and neck cancer. Nephrotoxicity is a well-documented adverse effect of cisplatin, which is exacerbated by dehydration, a common complication in this group of patients. This study prospectively assessed the utility of urine specific gravity (USG) as a guide for fluid replacement, and its preventive effect in cisplatin induced nephrotoxicity. Methods: Patients with head and neck cancer who received CRT with weekly cisplatin at our institution were included in the analysis. All patients received 1 L normal saline (NS) with 1 g of magnesium and 10 mEq of potassium pre and post cisplatin. USG was measured weekly, patients with USG>1.020 was considered dehydrated and received 2 L NS twice weekly. Those patients with USG>1.025 while on the twice-weekly regimen were deemed very dehydrated and received 2 L NS daily. The primary objective was renal toxicity of any grade. Results: 44 patients were identified and completed CRT in less than 7.5 weeks. Eighteen of 44 patients (41%) had initial USG>1.020 and were started on NS twice weekly. By week 5, 44 of 44 patients (100%) needed supplemental fluid hydration with only 4 of 44 (9%) requiring daily IV fluids (IVF). No patient experienced renal toxicity of any grade. Five patients (11%) had grade I hypomagnesemia. Conclusion: USG is a very sensitive marker of dehydration and can be used as a guide for fluid replacement which can minimize cisplatin induced nephrotoxicity in this population.

Abstract C185: Head and neck squamous carcinoma cells are susceptible to the attenuated vesicular stomatitis virus expressing suicide genes

Background: The predominant loco‐regional progression of Head and Neck Squamous Cell Carcinoma (HNSCC) makes it suitable for testing oncolytic viruses. Recent work from several laboratories including ours has focused on developing vesicular stomatitis virus (VSV) as a replication‐competent anticancer viral vector. Attenuated strains, such as M protein mutant VSV (M51R) are more likely to be promoted in clinical research. The major shortcoming of viral therapy is related to the large proportion of tumor cells remaining uninfected. We are addressing this limitation in two ways: the expression of the cytosine deaminase‐uracil phosphoribosyltransferase (C:U) suicide gene by the rVSV vector, expected to produce a strong bystander effect and the exploitation of the radiosensitizing potential of the 5‐fluorouracil (5‐FU) chemo‐drug produced intratumorally, as well as of the VSV virus itself. Methods: We determined the susceptibility to oncolytic VSV in a collection of HNSCC cell lines and in patient HN primary tumor cells by measuring: 1) the level of GFP expression after infection with rVSV‐GFP and M51R‐GFP; 2) the viral production by plaque assay and 3) cell death by Trypan blue exclusion. The extent of defectiveness in interferon pathways was tested by employing pre‐treatment with IFN and INF‐blocking antibodies before the infection with the oncolytic VSV. We have generated the rVSV‐C:U and M51R‐C:U viruses and we tested our collection of HNSCC cell models to infection with these viruses in the presence and absence of 5‐fluorocytosine. SQ20B cell line is a model of radiation resistant HNSCC. Regular SQ20B and SQ20B infected with low‐dose M51R‐VSV were evaluated by clonogenic assay. Results: 1) All HNSCC cell models tested are susceptible to the infection with the rVSV but many present a degree of resistance to the attenuated M51R‐VSV. 2) Human Primary HNSCC cells are more resistant than the HNSCC cell lines to the M51R‐VSV; 3) The activation of IFN pathways is contributing to the resistance to M51R‐VSV. 4) Addition of the suicide gene C:U to the attenuated VSV model significantly increased the oncolytic effect in vitro; 5) HNSCC cells infected with M51R‐VSV become more radiation sensitive. Conclusions: The decreased oncolytic effect of the attenuated M51R‐VSV can be overcome by the expression of suicide genes such as the yeast C:U fusion model. The demonstrated radiosensiting potential of the M51R‐VSV virus as well as the known radiosensitizing effect of the generated chemotherapeutic 5‐FU can be further exploited against the loco‐regional HNSCC tumors. Finally, we have important new information, both from cell lines and patient tissues, for proof‐of‐principle that cancers can down‐regulate antiviral responses. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C185.