Citations

The National Heart, Lung, and Blood Institute in collaboration with the American Society for Apheresis, convened a State of the Science Symposium in November of 2012 due to the expanding application of therapeutic apheresis despite the lack of well‐designed research to address its efficacy. This article reviews the opportunities that were presented at this meeting in the area of cardiovascular disease (CVD), specifically the use of columns to adsorb autoantibodies in dilated cardiomyopathy or damaging lipids in peripheral vascular disease. Understanding how absorption of these pathologic substances alters the inflammatory response in these disorders is important for the application of these technologies to the treatment of CVD. J. Clin. Apheresis 30:183–187, 2015. © 2014 Wiley Periodicals, Inc.

Background. Appropriate recommendations for a followup exam after an index colonoscopy are an important quality indicator. Lack of knowledge of polyp pathology at the time of colonoscopy may be one reason that followup recommendations are not made. Aim. To describe and compare the accuracy of followup recommendations made at colonoscopy based on the size and number of polyps with recommendations made at a later date based on actual polyp pathology. Methods. All patients who underwent screening and surveillance colonoscopy from March, 2012, to August, 2012, were included. Surveillance recommendations from the endoscopy reports were graded as “accurate” or “not accurate” based on the postpolypectomy surveillance guidelines established by US Multisociety Task Force on Colon Cancer. Polyp pathology was then used to regrade the surveillance recommendations. Results. Followup recommendations were accurate in 759/884 (86%) of the study colonoscopies, based upon size and number of polyps with the assumption that all polyps were adenomatous. After incorporating actual polyp pathology, 717/884 (81%) colonoscopies had accurate recommendations. Conclusion. In our practice, the knowledge of actual polyp pathology does not change the surveillance recommendations made at the time of colonoscopy in the majority of patients.

Abstract So far, therapeutic vaccination with allogeneic cancer cells has been only marginally effective. A reason for failure could stem from the fact that vaccine cells are usually cultured in air (pO2=20 kPa), while tumors in situ are often highly hypoxic. Hence, it is possible that vaccine cells expressed antigens differently than tumor cells in situ. We postulate that cells grown at low pO2 provide a better antigen match to tumors in situ and could be more effective vaccines. We tested the former hypothesis by comparing prostate cancer (CaP) cells propagated at pO2 = 2 kPa and 20 kPa. To identify potential tumor-associated antigens, we prepared CaP cell lysates, resolved them by 2D electrophoresis and immunoblotting using spontaneous antibodies from plasma derived from CaP patients and control subjects. Antibody-labeled spots were analyzed by MALDI-TOF mass spectrometry. Among identified molecules, we selected hypoxia-regulated HSP70 and hnRNP L and hypoxia-independent HSP60 and determined by ELISA the frequency of plasma samples reacting with these molecules two standard deviations above their reaction with normal sera. Frequency of HSP60-reactive plasma was 1/76 in healthy controls (HC; 1.3%), while it was 7/54 in CaP patients (13.0%; p<0.05). The corresponding values were 1/14 in colorectal cancer (7.1%), 1/10 in lung cancer (LC; 10.0%), 1/20 in renal cell carcinoma (5.0%) and 0/17 in rheumatoid arthritis (RA; 0%), not different from healthy controls. These data suggest that CaP patients develop humoral immunity to HSP60. Levels of autoantibodies to HSP70 in CaP patients (2/38, 5.3%) did not differ from HC (2/54, 3.7%) while they did differ from HC in LC (2/10, 20.0%) and RA (3/17, 17.7%). Similarly, frequency of autoantibodies to hnRNP L did no differ between HC (3/49, 6.1%) and CaP patients (2/38, 5.3%). Further, we evaluated the expression of hnRNP L protein in native CaP tissue by Western blot. In contrast to the levels of autoantibodies in plasma, hnRNP L antigen was present at twice the levels in CaP tissue (N=8) than in control benign prostate tissue (N=4; p<0.05). Overall, our results suggest that it is worthwhile to pursue evaluating of HSP60-specific autoantibodies as a CaP-associated marker. Currently, we are analyzing HSP60 and hnRNP L (hypoxia-regulated) protein and transcript expression by immunohistochemistry and PCR, respectively, in a large patient cohort. This approach could validate the use of hypoxia-sensitive molecules as effective prognostic biomarkers and help develop better therapy for CaP and, possibly, other tumors. Support: DOD PC094680 and PCF Creativity Award (both to CRG). Citation Format: Tangeng Ma, Abdelouahid Elkhattouti, Farhad Kosari, R. Jeffrey Karnes, John C. Cheville, George Vasmatzis, Stanimir Vuk-Pavlović, Christian R. Gomez. Hypoxia as a tool for identifying prostate cancer-associated antigens. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4056. doi:10.1158/1538-7445.AM2013-4056

Abstract Enzymatic degradation of hyaluronan (HA), a key component of the extracellular matrix (ECM), can enhance tumor perfusion, improve delivery of chemotherapeutics, and enhance the effects of anti-tumor agents. HA accumulation has been correlated with local invasion, the presence of distal metastasis, higher tumor grade, and poorer overall survival. PEGPH20, a pegylated form of recombinant human hyaluronidase PH20, is an investigational therapeutic agent under clinical development for the treatment of patients with solid tumors that may accumulate HA. Preclinical studies have demonstrated that sustained HA removal, accomplished with PEGPH20, inhibits tumor growth and enhances chemotherapeutic activity in HA-rich xenografts and genetically engineered mouse tumor models. Twenty-six patients with advanced solid tumors were enrolled in a Phase 1 multi-center trial. Patients received weekly or twice weekly doses of IV PEGPH20 (0.5 - 5 μg/kg) for the first 4-week cycle, followed by once-weekly dosing for the subsequent 4-week cycles. Serial blood samples were drawn from each patient, and plasma concentrations were measured by an ultrasensitive hyaluronidase activity assay to assess PEGPH20 pharmacokinetics (PK). Plasma levels of HA catabolites were measured using a quantitative HPLC method to characterize PEGPH20 pharmacodynamics (PD). Other measures of PD activity were evaluated in selected patients, including DCE-MRI, DW-MRI, 18FDG-PET, textural analysis on CT, and histochemical staining of HA in tumor biopsies collected both before and after PEGPH20 treatment. Peak plasma PEGPH20 concentrations increased with dose, and plasma pharmacokinetics (PK) were well described by a linear PK model. Pre-treatment plasma HA levels were typically <1 μg/mL and increased in a dose-dependent fashion after PEGPH20 treatment. Increased plasma HA corresponded with decreased HA staining in patients with available tumor biopsies. DCE-MRI analysis indicated early (24-48 hr) and rapid increase in tumor perfusion compared to baseline in 4 patients with serial MRI assessments. Pharmacodynamic activity was also demonstrated when pre-treatment 18FDG-PET scans were compared with images collected at scheduled times after PEGPH20 dosing. Reduction in FDG uptake exceeding 25% was demonstrated in 3 of 4 patients after one cycle of treatment, consistent with a partial metabolic response. These data are consistent with the mechanism of action reported in preclinical models, and results support continued evaluation of PEGPH20 in combination with anti-tumor agents via modification of the ECM. Citation Format: Ping Jiang, Daniel C. Maneval, Ramesh K. Ramanathan, Jeffrey R. Infante, Mitesh Borad, Alberto Bessudo, Patricia LoRusso, Barry J. Sugarman, Deborah Carson, Marie A. Printz, Curtis B. Thompson, Paneer Selvam, Joy Zhu, Ronald Korn, H Michael Shepard, Gregory I. Frost. Phase 1 pharmacodyamic activity of multiple-dose PEGylated hyaluronidase PH20 (PEGPH20) in patients with solid tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3375. doi:10.1158/1538-7445.AM2013-3375

Abstract Background: The potential for exploiting BRCA deficiencies with DNA repair inhibitors has both pre-clinical and clinical support. ABT-888 (veliparib), a DNA repair inhibitor initially thought to target Poly(ADP-Ribose) Polymerases (PARP), has demonstrated in vitro inhibition of BRCA1 and BRCA2 deficient mouse embryonic stell cells, with a larger effect on BRCA1 cells. We report on the pre-planned interim analysis of the efficacy of single agent veliparib in patients with either BRCA1 or BRCA2-associated stage IV breast cancer. Methods: BRCA 1 or 2 carrier patients with stage IV breast cancer, with measurable disease, without prior exposure to a PARP inhibitor or a platinum compound in the metastatic setting, were eligible. Velapirib was administered orally, at doses of 400 mg twice daily. Dose adjustments based on toxicity were permitted. Patients progressing on velapirib alone received carboplatin at an AUC of 5, IV, given Q 21 days, and velapirib 150 mg twice daily (the maximum tolerated dose [MTD] of the combination from our completed Phase I study: J Clin Oncol 30, 2012 [suppl; abstr 1024]). Patients were to be accrued from 7 NCI NO1- supported consortia. Initially 10 patients were to be accrued to each stratum (BRCA1 and BRCA2) to provide evidence of single agent activity. If there was sufficient activity to warrant consideration of velapirib as single agent therapy (defined as 2 or more confirmed partial [PR] or better responses out of 10 per stratum), an additional 12 patients would be accrued per stratum. Results: 20 evaluable patients (11 BRCA1 and 9 BRCA2 [1 in screening]) have been accrued, the majority with lung or liver as visceral metastatic sites of disease. Median age (range) is 46 (29-68) years. Tumors from 9 patients were hormone receptor positive. BRCA1 cohort: 4 of 11 patients are off treatment at a median of 2 months (1-4); 1 patient stopped velapirib due to toxicity (grade 2 rash/pruritus, grade 2 vomiting), 3 stopped for progressive disease (one with an unconfirmed PR). Seven patients are still on single agent veliparib with 1 unconfirmed PR, and 1 patient with two evaluations showing stable disease. BRCA2 cohort: 2 patients are off treatment at 2 months for progressive disease, 7 are still on treatment with 1 confirmed PR, and 3 unconfirmed PRs. Data on patients receiving combination of velapirib and carboplatin after progression is too early. Treatment-related toxicity is being updated and has so far been reported from 14 patients: 1 patient had grade 3 fatigue, 1 patient with liver metastasis had both grade 3 alanine aminotransferase elevation and grade 3 abdominal pain. Grade 2 toxicities occurring in more than 1 patient included nausea/vomiting (6 patients), chills (2 patients), and fatigue (2 patients). Conclusion: Velapirib has single agent activity in both BRCA1 and BRCA2-associated stage IV breast cancer patients, and is well-tolerated. Mature response, treatment, and toxicity data will be presented. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-05.