Journal of Cancer 2011, 2 142 Journal of Cancer 2011; 2:142-152 © Ivyspring International Publisher. All rights reserved Research Paper An Effective Personalized Approach to a Rare Tumor: Prolonged Survival in Metastatic Pancreatic Acinar Cell Carcinoma Based on Genetic Analysis and Cell Line Development Matthew D. Armstrong 1, Daniel Von Hoff 5, Bruce Barber 2, Laura A. Marlow3, Christina von Roemeling3, Simon J. Cooper3, Patrick Travis6, Elizabeth Campbell5, Ricardo Paz-Fumagalli4, John A. Copland3, Gerardo Colon-Otero1 1. Division of Hematology/Oncology; 2. Department of Laboratory Medicine and Pathology; 3. Department of Cancer Biology; 4. Department of Diagnostic Radiology, Mayo Clinic, Jacksonville, Florida, USA; 5. The Translational Genomics Research Institute (TGen), Phoenix AZ, USA; 6. Highlands Oncology Group, Bentonville AR, USA. Corresponding author: Dr. Gerardo Colon-Otero, Division of Hematology/Oncology, Mayo Clinic, Jacksonville, Florida, 32224. [email protected] Received: 2011.01.12; Accepted: 2011.02.23; Published: 2011.03.08 Abstract Acinar cell carcinoma of the pancreas is an uncommon malignancy, accounting for less than 1% of all pancreatic neoplasms. Because of its rarity, only a few retrospective studies are available to help guide management. We report the case of a patient with metastatic ACC who achieved prolonged survival as a result of personalized treatment designed in part on the basis of molecular and in-vitro data collected on analysis of the tumor and a cell line developed from the liver metastasis. To our knowledge, this represents the first human cell line of ACC. The molecular findings on this case and this patient’s cell line may be of use in the management of future cases of this rare tumor and allow the identification of potential novel targets for the effective treatment of this disease. Key words: acinar cell pancreatic cancer, prolonged survival, personalized medicine, cell line Introduction Although the most common cells in the pancreas with the more common and deadlier pancreatic ade- are the acinar cells, malignant transformation of these nocarcinomas. ACC affects males more commonly cells is very rare. Pancreatic adenocarcinomas, de- than females1-8. rived from epithelial cells lining the pancreatic ducts There are also significant differences in the clin- are the most common pancreatic malignancy followed ical presentation of ACC as compared to pancreatic by neuroendocrine tumors, with acinar cell carcino- adenocarcinoma. Contrary to pancreatic adenocarci- mas (ACC) of the pancreas representing less than 1% noma cases, patients with early stage ACC frequently of all pancreatic tumors1-8. Fewer than 50 cases of present with abdominal pain and bloating as the ACC are diagnosed annually in the USA8. Patients dominant symptoms. Occasionally, ACC tumors with ACC are more likely to present at a younger age produce excessive lipase causing systemic fat necro- and with earlier stage tumors as compared to patients sis9-16. Clinical manifestations of this syndrome of fat http://www.jcancer.org Journal of Cancer 2011, 2 143 necrosis can include panniculitis, discrete skin lesions had sections submitted and processed for standard and subcutaneous nodules. Pathologic fractures re- IHC. IHC was performed for Her2/neu, estrogen re- lated to intraosseus necrosis have been described as ceptor, progesterone receptor, c-kit, epidermal growth well. Laboratory abnormalities include elevated se- factor receptor (EGFR) and cyclooxygenase 2 (COX2) rum lipase levels, eosinophilia, and occasionally ele- ERCC1 (DNA excision repair protein), p-glycoprotein, vated serum alpha fetoprotein levels. dihydrofolate reductase (DHFR), TYMS, secreted Because of the rarity of this malignancy, studies protein acidic cysteine-rich (SPARC, osteonectin), have primarily consisted of retrospective chart re- platelet derived growth factor (PDGFR) and topoi- views and case reports. Very limited data are availa- somerase II alpha (TOP2A). IHC was performed by ble about effective systemic treatments for patients Caris Life Science (Phoenix, AR). Human epidermal with recurrent, unresectable or metastatic disease. The growth factor receptor 2 (HER2) and epidermal rarity of the disease has thus far precluded systematic growth factor receptor (EGFR) were stained as speci- approach to treatment through clinical trials, and only fied by the vendor (DAKO, Copenhagen, Denmark). a handful of retrospective reviews and case reports All other antibodies were purchased from commercial describing empiric treatments have been published1-8, sources and visualized with a DAB biotin-free poly- 17-26. mer detection kit. Appropriate positive control tissue We report a case of acinar cell carcinoma in was used for each antibody. Negative control slides which the patient had extended survival with meta- were stained by replacing the primary antibody with static disease. We attribute his extended survival to an an appropriately matched isotype-negative control aggressive multi-disciplinary approach involving a reagent. All slides were counterstained with hema- variety of localized and systemic treatments. Moreo- toxylin as the final step and cover slipped. All slides ver, systemic treatments were guided by molecular were evaluated semiquantitatively on a scale of 0 (no and phenotypic studies performed on the patient’s staining) to 4+ and by the percentage of the tumor tumor tissue biopsies and derivative cell lines. This cells showing the reactivity by a single pathologist. multi-disciplinary approach with translational studies IHC was considered positive for target if staining was offers a potential strategy for management of acinar 2+ in 30% of cells. cell carcinomas in particular and rare malignancies in Gene Expression Analysis Using DNA Microarrays general. The frozen tumor fragments for microarray Materials and Methods (MA) were placed in a glass tube on 0.5 mL of frozen Serum Chemistries 0.5 M guanidine isothiocyanate solution and thawed and homogenized with a Covaris S2 (Covari, Woburn, Peripheral blood studies were monitored, in- MA). TriZol (0.5 mL) was added and mixed, and the cluding serum lipase, alpha fetoprotein, alkaline solution was heated to 65°C for 5 minutes and then phosphatase, and CEA levels. Normal references cooled on ice and phase separated by adding chloro- range levels are as follows for serum lipase (7-60 form and centrifugation. An equal volume of 70% IU/L), alpha fetoprotein (0.0 – 5.9 ng/ml), alkaline ethanol was added to the aqueous phase, which was phosphatase (45 – 115 IU/L) and CEA (0 – 3.0 ng/ml chromatographed on a Qiagen Rneasy column (Qi- for non-smoker). agen, Germantown, MD). RNA was bound and then Biopsies and Immunhistochemistry eluted. RNA was tested for integrity by assessing the ratio of 28S to 18S ribosomal RNA on an Agilent Bi- Since ACC is a rare cancer with no standard of oAnalyzer (Agilent, Santa Clara, CA). Tumor RNA care, biopsies were requested by the patient for the and RNA from a sample of a normal pancreas were purpose of establishing cell lines for therapeutic drug converted to cDNA and labeled during T7 polymer- testing as well as RNA and protein analysis. IRB ase amplification with contrasting fluor tagged (Cy3, permission was obtained for this procedure. Biopsies Cy5) cytidine triphosphate. The labeled tumor and its were performed using needle biopsies. For needle tissue of origin reference were hybridized to an Ag- biopsies, two to three 18-gauge needle core biopsies ilent HIAv2 60-mer oligo array chip with 17,085 were performed. For DNA MA analysis, tissue was unique probes. Hybridization signals were acquired immediately frozen and shipped on dry ice to a cen- and normalized using Agilent's Feature Extraction tral Clinical Laboratory Improvement Amendments- software (version 7.1). The MA was considered posi- certified laboratory (Caris Life Sciences, Phoenix, AZ). tive for a target if the difference in expression for a For immunohistochemistry (IHC), paraffin blocks gene between tumor and control organ tissue was at a were shipped on cold packs. For IHC studies, the significance level of p<0.05. formalin-fixed paraffin-embedded tumor samples http://www.jcancer.org Journal of Cancer 2011, 2 144 Cell line and animal model development for acinar cell cells were collected and counted on a Coulter Particle pancreatic cancer Counter (Beckman, Brea, CA). The mean and stand- Since no standard of care exists for acinar cell ard deviation were calculated and plotted. pancreatic cancer, the patient requested a liver biopsy To determine synergy of combinatorial therapy, of the tumor to attempt to develop a cell line and test the concentration of each drug where 50% of growth drug sensitivity. Two such procedures occurred, one is inhibited (IC50) is first determined by dose concen- in May 2005 and the other in May 2008. The procedure tration curves. Combining the drugs at a constant was performed under local anesthetic and ultrasound ratio at, below and above their IC50 concentrations is guidance after obtaining consent from the patient. used to determine whether their antiproliferative ac- Biopsied tissue was frozen in liquid nitrogen as well tivity is synergistic, additive or antagonistic. Results as transported to the laboratory in sterile media and from this assay were used to calculate a combination tissue was prepared for cell culture. Half of the tissue index (CI) value using the software program CalcuS- was minced, washed in PBS (Cellgro, Herndon, VA) yn (BioSoft, Ferguson, MO). The CI equation in Cal- and cultured in DMEM medium (Cellgro) supple- cuSyn is based on the multiple drug-effect equation of mented with 10% fetal bovine serum (Hyclone, Logan, Chou and Talalay (27). CI values less than 1 indicate a UT), non – essential amino acids (Cellgro), and peni- synergistic effect while CI values above 1 are indica- cillin-streptomycin-amphotericin B (Cellgro) at 37ºC tive of antagonism. in a humidified atmosphere with 5% CO2. The biop- Statistical Analysis sied tissue collected May 2005 grew in culture up to Data are presented as the mean SD and com- passage 16. These primary cells (PanJ1) were drug parisons of treatment groups were analyzed by tested at passage 3.