Elizabeth A. Sugar

Distinct Risk Factor Profiles for Human Papillomavirus Type 16–Positive and Human Papillomavirus Type 16–Negative Head and Neck Cancers

BACKGROUND High-risk types of human papillomavirus (HPV), including HPV-16, cause a subgroup of head and neck squamous cell carcinomas (HNSCCs). We examined whether the risk factors for HPV-16-positive HNSCCs are similar to those for HPV-16-negative HNSCCs in a hospital-based case-control study. METHODS Case subjects (n = 240) diagnosed with HNSCC at the Johns Hopkins Hospital from 2000 through 2006 were stratified by tumor HPV-16 status as determined by in situ hybridization. Two control subjects (n = 322) without cancer were individually matched by age and sex to each HPV-16-positive and HPV-16-negative case subject. Data on risk behaviors were obtained by use of audio computer-assisted self-interview technology. Multivariable conditional logistic regression models were used to estimate the odds ratios (ORs) for HPV-16-positive HNSCC and HPV-16-negative HNSCC associated with risk factors. All statistical tests were two-sided. RESULTS HPV-16 was detected in 92 of 240 case subjects. HPV-16-positive HNSCC was independently associated with several measures of sexual behavior and exposure to marijuana but not with cumulative measures of tobacco smoking, alcohol drinking, or poor oral hygiene. Associations increased in strength with increasing number of oral sex partners (P(trend) = .01) and with increasing intensity (joints per month, P(trend) = .007), duration (in years, P(trend) = .01), and cumulative joint-years (P(trend) = .003) of marijuana use. By contrast, HPV-16-negative HNSCC was associated with measures of tobacco smoking, alcohol drinking, and poor oral hygiene but not with any measure of sexual behavior or marijuana use. Associations increased in strength with increasing intensity (cigarettes per day), duration, and cumulative pack-years of tobacco smoking (for all, P(trend) < .001), increasing years of heavy alcohol drinking (> or = 15 years of 14 drinks per week; P(trend) = .03), and increasing number of lost teeth (P(trend) = .001). Compared with subjects who neither smoked tobacco nor drank alcohol, those with heavy use of tobacco (> or = 20 pack-years) and alcohol had an increased risk of HPV-16-negative HNSCC (OR = 4.8, 95% confidence interval [CI] = 1.8 to 12) but not of HPV-16-positive HNSCC (OR = 0.67, 95% CI = 0.29 to 1.9). CONCLUSIONS HPV-16-positive HNSCCs and HPV-16-negative HNSCCs have different risk factor profiles, indicating that they should be considered to be distinct cancers.

Combined DNA methyltransferase and histone deacetylase inhibition in the treatment of myeloid neoplasms

Optimal reexpression of most genes silenced through promoter methylation requires the sequential application of DNA methyltransferase inhibitors followed by histone deacetylase inhibitors in tumor cell cultures. Patients with myelodysplastic syndrome or acute myeloid leukemia (AML) were treated with the methyltransferase inhibitor 5-azacitidine (aza-CR) followed by the histone deacetylase inhibitor sodium phenylbutyrate. Major responses associated with cytogenetic complete response developed in patients receiving prolonged dosing schedules of aza-CR. Bisulfite sequencing of the p15 promoter in marrow DNA during the first cycle of treatment showed heterogeneous allelic demethylation in three responding patients, suggesting ongoing demethylation within the tumor clone, but no demethylation in two nonresponders. Six of six responding patients with pretreatment methylation of p15 or CDH-1 promoters reversed methylation during the first cycle of therapy (methylation-specific PCR), whereas none of six nonresponders showed any demethylation. Gene demethylation correlated with the area under the aza-CR plasma concentration-time curve. Administration of both drugs was associated with induction of acetylation of histones H3 and H4. This study provides the first demonstration that molecular mechanisms responsible for responses to DNA methyltransferase/histone deacetylase inhibitor combinations may include reversal of aberrant epigenetic gene silencing. The promising percentage of major hematologic responses justifies the testing of such combinations in prospective randomized trials.

Analysis of Fluorouracil-Based Adjuvant Chemotherapy and Radiation After Pancreaticoduodenectomy for Ductal Adenocarcinoma of the Pancreas: Results of a Large, Prospectively Collected Database at the Johns Hopkins Hospital

PURPOSE To examine the efficacy of adjuvant chemoradiotherapy after pancreaticoduodenectomy (PD) for pancreatic adenocarcinoma (PC) in patients undergoing resection at Johns Hopkins Hospital (JHH; Baltimore, MD). PATIENTS AND METHODS Between August 30, 1993, and February 28, 2005, a total of 908 patients underwent PD for PC at JHH. A prospective database was reviewed to determine which patients received fluorouracil (FU) -based CRT. Excluded patients had metastatic disease, died 60 or fewer days after PD, received preoperative therapy, an experimental vaccine, adjuvant chemotherapy or radiation alone. The final cohort includes 616 patients. RESULTS The median follow-up was 17.8 months (interquartile range, 9.7 to 33.5 months). Overall median survival was 17.9 months (95% CI, 16.3 to 19.5 months). Groups were similar with respect to tumor size, nodal status, and margin status, but the CRT group was younger (P < .001), and less likely to present with a severe comorbid disease (P = .001). Patients with carcinomas larger than 3 cm (P = .001), grade 3 and 4 (P < .001), margin-positive resection (P = .001), and complications after surgery (P = .017) had poor long-term survival. Patients receiving CRT experienced an improved median (21.2 v 14.4 months; P < .001), 2-year (43.9% v 31.9%), and 5-year (20.1% v 15.4%) survival compared with no CRT. After controlling for high-risk features, CRT was still associated with improved survival (relative risk = 0.74; 95% CI, 0.62 to 0.89). CONCLUSION These data suggest that adjuvant concurrent FU-based CRT significantly improves survival after PD for PC when compared with patients not receiving CRT. These data support the use of combined adjuvant CRT for PC.

Evaluation of Ipilimumab in combination with allogeneic pancreatic tumor cells transfected with a GM-CSF gene in previously treated pancreatic cancer

Preclinical reports support the concept of synergy between cancer vaccines and immune checkpoint blockade in nonimmunogenic tumors. In particular, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) antibodies have been successfully combined with GM-CSF cell-based vaccines (GVAX). Ipilimumab (anti-CTLA-4) has been tested as a single agent in patients with pancreatic ductal adenocarcinoma (PDA) resulting in a delayed response at a dose of 3 mg/kg. Our study evaluated ipilimumab 10 mg/kg (arm 1) and ipilimumab 10 mg/kg+GVAX (arm 2). A total of 30 patients with previously treated advanced PDA were randomized (1:1). Induction doses were administered every 3 weeks for a total of 4 doses followed by maintenance dosing every 12 weeks. Two patients in arm 1 showed evidence of stable disease (7 and 22 wk) but none demonstrated CA19-9 biochemical responses. In contrast, 3 patients in arm 2 had evidence of prolonged disease stabilization (31, 71, and 81 wk) and 7 patients experienced CA19-9 declines. In 2 of these patients, disease stabilization occurred after an initial period of progression. The median overall survival (OS) (3.6 vs. 5.7 mo, hazards ratio: 0.51, P=0.072) and 1 year OS (7 vs. 27%) favored arm 2. Similar to prior ipilimumab studies, 20% of patients in each arm had grade 3/4 immune-related adverse events. Among patients with OS>4.3 months, there was an increase in the peak mesothelin-specific T cells (P=0.014) and enhancement of the T-cell repertoire (P=0.031). In conclusion, checkpoint blockade in combination with GVAX has the potential for clinical benefit and should be evaluated in a larger study.

A lethally irradiated allogeneic granulocyte-macrophage colony stimulating factor-secreting tumor vaccine for pancreatic adenocarcinoma. A Phase II trial of safety, efficacy, and immune activation.

PURPOSE Surgical resection provides the only possibility of cure for pancreas cancer. A standard adjuvant approach has not been established. We tested the safety and efficacy of a granulocyte-macrophage colony-stimulating factor (GM-CSF)-based immunotherapy administered in patients with resected pancreatic adenocarcinoma. PATIENTS AND METHODS A single institution phase II study of 60 patients with resected pancreatic adenocarcinoma was performed. Each immunotherapy treatment consisted of a total of 5 × 108 GM-CSF-secreting cells distributed equally among 3 lymph node regions. The first immunotherapy treatment was administered 8 to 10 weeks after surgical resection. Subsequently, patients received 5-FU based chemoradiation. Patients who remained disease-free after completion of chemoradiotherapy received treatments 2 to 4, each 1 month apart. A fifth and final booster was administered 6 months after the fourth immunotherapy. The primary endpoint was disease free survival and secondary endpoints were overall survival and toxicity, and the induction of mesothelin specific T cell responses. RESULTS The median disease-free survival is 17.3 months (95% CI, 14.6-22.8) with median survival of 24.8 months (95% CI, 21.2-31.6). The administration of immunotherapy was well tolerated. In addition, the post-immunotherapy induction of mesothelin-specific CD8+ T cells in HLA-A1+ and HLA-A2+patients correlates with disease-free survival. CONCLUSIONS An immunotherapy approach integrated with chemoradiation is safe and demonstrates an overall survival that compares favorably with published data for resected pancreas cancer. These data suggest additional boost immunotherapies given at regular intervals beyond 1 year postsurgery should be tested in future studies, and provide the rationale for conducting a multicenter phase II study.

Allogeneic Granulocyte Macrophage Colony-Stimulating Factor–Secreting Tumor Immunotherapy Alone or in Sequence with Cyclophosphamide for Metastatic Pancreatic Cancer: A Pilot Study of Safety, Feasibility, and Immune Activation

Purpose: The combination of chemotherapy and immunotherapy has not been examined in patients with advanced pancreatic cancer. We conducted a study of two granulocyte macrophage colony-stimulating factor–secreting pancreatic cancer cell lines (CG8020/CG2505) as immunotherapy administered alone or in sequence with cyclophosphamide in patients with advanced pancreatic cancer. Experimental Design: This was an open-label study with two cohorts: cohort A, 30 patients administered a maximum of six doses of CG8020/CG2505 at 21-day intervals; and cohort B, 20 patients administered 250 mg/m2 of cyclophosphamide i.v. 1 day before the same immunotherapy given as in cohort A. The primary objective was to evaluate safety and duration of immunity. Secondary objectives included time to disease progression and median overall survival. Results: The administration of CG8020/CG2505 alone or in sequence with cyclophosphamide showed minimal treatment-related toxicity. Median survival values in cohort A and cohort B were 2.3 and 4.3 months, respectively. CD8+ T-cell responses to HLA class I–restricted mesothelin epitopes were identified predominantly in patients treated with cyclophosphamide + CG8020/CG2505 immunotherapy. Conclusion: Granulocyte macrophage colony-stimulating factor–secreting pancreatic cancer cell lines CG8020/CG2505 alone or in sequence with cyclophosphamide showed minimal treatment-related toxicity in patients with advanced pancreatic cancer. Also, mesothelin-specific T-cell responses were detected/enhanced in some patients treated with CG8020/CG2505 immunotherapy. In addition, cyclophosphamide-modulated immunotherapy resulted in median survival in a gemcitabine-resistant population similar to chemotherapy alone. These findings support additional investigation of cyclophosphamide with CG8020/CG2505 immunotherapy in patients with advanced pancreatic cancer.

A Live-Attenuated Listeria Vaccine (ANZ-100) and a Live-Attenuated Listeria Vaccine Expressing Mesothelin (CRS-207) for Advanced Cancers: Phase I Studies of Safety and Immune Induction

Purpose: Listeria monocytogenes (Lm)-based vaccines stimulate both innate and adaptive immunity. ANZ-100 is a live-attenuated Lm strain (Lm ΔactA/ΔinlB). Uptake by phagocytes in the liver results in local inflammatory responses and activation and recruitment of natural killer (NK) and T cells, in association with increased survival of mice bearing hepatic metastases. The Lm ΔactA/ΔinlB strain, engineered to express human mesothelin (CRS-207), a tumor-associated antigen expressed by a variety of tumors, induces mesothelin-specific T-cell responses against mesothelin-expressing murine tumors. These two phase I studies test ANZ-100 and CRS-207 in subjects with liver metastases and mesothelin-expressing cancers, respectively. Experimental Design: A single intravenous injection of ANZ-100 was evaluated in a dose escalation study in subjects with liver metastases. Nine subjects received 1 × 106, 3 × 107, or 3 × 108 colony-forming units (cfu). CRS-207 was evaluated in a dose-escalation study in subjects with mesothelioma, lung, pancreatic, or ovarian cancers. Seventeen subjects received up to 4 doses of 1 × 108, 3 × 108, 1 × 109, or 1 × 1010 cfu. Results: A single infusion of ANZ-100 was well tolerated to the maximum planned dose. Adverse events included transient laboratory abnormalities and symptoms associated with cytokine release. Multiple infusions of CRS-207 were well tolerated up to 1 × 109 cfu, the determined maximum tolerated dose. Immune activation was observed for both ANZ-100 and CRS-207 as measured by serum cytokine/chemokine levels and NK cell activation. In the CRS-207 study, listeriolysin O and mesothelin-specific T-cell responses were detected and 37% of subjects lived ≥15 months. Conclusions: ANZ-100 and CRS-207 administration was safe and resulted in immune activation. Clin Cancer Res; 18(3); 858–68. ©2011 AACR.

Therapeutic Efficacy of ABT-737, a Selective Inhibitor of BCL-2, in Small Cell Lung Cancer

Bcl-2 is a central regulator of cell survival that is overexpressed in the majority of small cell lung cancers (SCLC) and contributes to both malignant transformation and therapeutic resistance. We compared primary SCLC xenografts prepared from de novo human tumors with standard cell line-based xenografts in the evaluation of a novel and highly potent small molecule inhibitor of Bcl-2, ABT-737. ABT-737 induced dramatic regressions in tumors derived from some SCLC cell lines. In contrast, only one of three primary xenograft SCLC tumors showed significant growth inhibition with ABT-737. Explanations for this apparent dichotomy may include relatively low expression of Bcl-2 in the primary xenografts or inherent differences in the model systems. The addition of etoposide to ABT-737 in the primary xenografts resulted in significant decreases in tumor growth, underscoring the clinical potential of ABT-737 in combination therapy. To identify factors that may contribute to resistance to ABT-737 and related inhibitors, we isolated resistant derivatives of an initially sensitive cell line-based xenograft. Acquired resistance in this model was associated with decreases in the expression of the primary target Bcl-2, of proapoptotic partners of Bcl-2 (Bax and Bim), and of Bcl-2:Bim heterodimers. Expression profiling reveals 85 candidate genes demonstrating consistent changes in gene expression with acquired resistance. Taken together, these data have specific implications for the clinical development of Bcl-2 inhibitors for SCLC and broader implications for the testing of novel anticancer strategies in relevant preclinical models.

Six-month natural history of oral versus cervical human papillomavirus infection

Human papillomavirus (HPV) infection is etiologically associated with a subset of oral cancers, and yet, the natural history of oral HPV infection remains unexplored. The feasibility of studying oral HPV natural history was evaluated by collecting oral rinse samples on 2 occasions at a 6‐month interval from 136 HIV‐positive and 63 HIV‐negative participants. Cervical vaginal lavage samples were concurrently collected for comparison. HPV genomic DNA was detected in oral and cervical samples by consensus primer PCR and type‐specified for 37 HPV types. The six‐month cumulative prevalence of oral HPV infection was significantly less than for cervical infection (p < 0.0001). HIV‐positive women were more likely than HIV‐negative women to have an oral (33 vs. 15%, p = 0.016) or cervical (78 vs. 51%, p < 0.001) infection detected. Oral HPV infections detected at baseline were as likely as cervical infections to persist to 6 months among HIV‐negative (60% vs. 51%, p = 0.70) and HIV‐positive (55% vs. 63%, p = 0.27) women. Factors that independently elevated odds for oral HPV persistence differed from cervical infection and included current smoking (OR = 8, 95% CI = 1.3–53), age above 44 years (OR = 20, 95% CI = 4.1–83), CD4 < 500 (OR = 6, 95% CI = 1.1–26), use of HAART therapy (OR = 12, 95% CI = 1.0–156), and time on HAART therapy (trend p = 0.04). The rate of oral HPV infections newly detected at follow‐up was significantly lower than cervical infection among HIV‐positive (p < 0.001) and HIV‐negative women (p < 0.001). Our study not only demonstrates that it is feasible to study the natural history of oral HPV infection with oral rinse sampling, but also indicates that oral and cervical HPV natural history may differ.

A Phase I Trial of a Human Papillomavirus DNA Vaccine for HPV16+ Cervical Intraepithelial Neoplasia 2/3

Purpose: To evaluate the safety and immunogenicity of a therapeutic human papillomavirus (HPV)16 DNA vaccine administered to women with HPV16+cervical intraepithelial neoplasia (CIN)2/3. Experimental Design: This phase I trial incorporated the standard ′3+3″ dose-escalation design with an additional 6 patients allocated to the maximally tolerated dose. Healthy adult women with colposcopically directed, biopsy-proven HPV16+ CIN2/3 received 3 i.m. vaccinations (0.5, 1, or 3 mg) of a plasmid expressing a Sig-E7(detox)-heat shock protein 70 fusion protein on days 0, 28, and 56, and underwent standard therapeutic resection of the cervical squamocolumnar junction at day 105 (week 15). The safety and immunogenicity of the vaccine and histologic outcome based on resection at week 15 were assessed. Results: Fifteen patients were evaluable (3 each at 0.5 and 1mg, 9 at 3 mg). The vaccine was well tolerated: most adverse events were mild, transient injection-site discomfort; no dose-limiting toxicities were observed. Although HPVE7-specific T-cell responses to E7 detected by enzyme-linked immunospot assays (IFN-γ) were of low frequency and magnitude, detectable increases in response subsequent to vaccination were identified in subjects in the second and third cohorts. Complete histologic regression occurred in 3 of 9 (33%; 7-70% confidence interval) individuals in the highest-dose cohort. Although the difference is not significant, it is slightly higher than would be expected in an unvaccinated cohort (25%). Conclusions: This HPV16 DNA vaccine was safe and well tolerated. Whereas it seems possible to elicit HPV-specific T-cell responses in patients with established dysplastic lesions, other factors are likely to play a role in lesion regression.