Abstract LB048: An adjuvant personalized neoantigen peptide vaccine for the treatment of malignancies (PGV-001)

Background: The majority of novel cancer immunotherapies rely on adequate priming of T cells to tumor-specific neoantigens, which is believed to be lacking in patients who do not respond to therapy. We developed a personalized genomic vaccine (PGV-001) in which patient-specific synthetic neoantigen peptides (25 mer),are formulated and administered to patients with multiple cancer types in the adjuvant setting (NCT02721043). Methods: This trial enrolled patients whom had undergone curative-intent surgery (solid tumor patients) or autologous stem cell transplant (multiple myeloma patients), and for whom there was >30% chance of recurrence. Sequencing of tumor and germline DNA and RNA was performed and the OpenVax custom computation pipeline was used to identify candidate neoantigens; this platform ranks transcribed mutations using predicted MHC-I binding affinity and neoantigen abundance. A maximum of 10 peptides were synthesized per patient. Peptides were administered over the course of 27 weeks with poly-ICLC and a tetanus helper peptide. Primary objectives were to determine the safety and tolerability of vaccination, feasibility of vaccine production and administration, and immunogenicity. Results: Within 15 patients enrolled, the OpenVax pipeline identified an average of 67.1 neoantigens/patient (range 8-193), only two patients did not have adequate number of neoantigens identified to synthesize 10 peptides. 13 of the 15 patients received PGV-001, including 10 patients with solid tumor diagnoses and 3 patients with multiple myeloma, 11 of whom received all 10 doses, while 1 experienced progression of disease while on treatment. The vaccine was well tolerated, with grade 1 injection site reactions in 31% of patients, and grade 1 fever in one patient; there were no other significant adverse events. While one patient was lost to follow-up, of the remaining 12 patients the median progression-free survival from the time of their surgery or transplant of 618 days. With a mean follow-up of 925 days, 4 patients remain without evidence of disease, 4 patients are receiving subsequent lines of therapy, and 4 patients have died, though notably only two with documented recurrence of their malignancy. Initial analysis of the patient samples analyzed confirms immunogenicity. T cell responses were measured using ex vivo ELISpot and intracellular cytokine staining following expansion with neoantigen peptide libraries, both demonstrating induction of IFN-gamma, TNF-alpha and IL-2. Notably, robust T cell reactivity was only seen at the completion of all 10 vaccines, supporting the need for a prolonged schedule. Conclusions: PGV-001 was successfully synthesized for 15 patients and administered successfully to 13 patients without significant adverse events. Immune monitoring of immunogenicity is ongoing, with initial analysis demonstrating induction of neoantigen-specific CD4 and CD8 T cell expansion.

Citation Format: Thomas Urban Marron, Mansi Saxena, Nina Bhardwaj, Marcia Meseck, Alex Rubinsteyn, John Finnigan, Julia Kodysh, Ana Blazquez, Tim O'Donnel, Mathew Galsky, Deborah Doroshow, Brett Miles, Krysztof Misiukiewicz, Hanna Irie, Amy Tiersten, Samir Parekh, Marshall Posner, Andrea Wolf, John Mandeli, Rachel Brody, Sacha Gnjatic, Eric Schadt, Philip Friedlander, Jeffrey Hammerbacher. An adjuvant personalized neoantigen peptide vaccine for the treatment of malignancies (PGV-001) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB048.

Abstract CT262: Multicenter, phase I/II trial of anastrozole, palbociclib, trastuzumab, and pertuzumab in HR-positive, HER2-positive metastatic breast cancer

Background: Overexpression or amplification of HER2 occurs in approximately 15-20% of patients and roughly half of these tumors are hormone receptor (HR) positive. The use of aromatase inhibitors in the metastatic setting is well established while significant improvement in overall survival has been established with the use of trastuzumab or pertuzumab in HER2-overexpressing tumors. This study will examine the combination of endocrine therapy, palbociclib, and dual HER2 therapy with pertuzumab and trastuzumab in women with metastatic HR+, HER2+ breast cancer. Trial Design: Multicenter, phase I/II trial of Anastrozole, Palbociclib, Trastuzumab and Pertuzumab in HR+, Her2+ metastatic breast cancer. Eligibility Criteria: Newly diagnosed stage IV HR+, HER2+ breast cancer patients. Specific Aims: Phase I: To determine the maximum dose tolerated of palbociclib. Phase II: To determine the clinical benefit rate (CBR) of treatment with anastrozole, palbociclib, trastuzumab, and pertuzumab in HR+, HER2+ metastatic breast cancer patients. Exploratory: Examine potential biomarkers of response to palbociclib including expression of cyclin D1, cyclin E1 and E2, CDK 2, CDK 4, CDK 6, retinoblastoma, phosphorylated retinoblastoma, and p16. RNA sequencing will be used to assess for other predictors of response in an unbiased manner to assess for correlation with inhibition of Ki-67 and phosphorylated retinoblastoma expression as well as evaluate for potential mechanisms of resistance. Methods: This study will evaluate the maximum tolerated dose (MTD) of the Anastrozole, Palbociclib, Trastuzumab and Pertuzumab. Once the MTD is reached, we will assess the clinical benefit rate using a Simon's II stage design among a maximum 30 patients. Accrual: Maximum of 36 subjects. Current Enrollment: Enrollment to phase I ended in October 2018 with one dose escalation to palbociclib 125mg, at which level one DLT was observed. Thus, the MTD was determined at palbociclib 125 mg and subsequent phase II patients will be treated at this dose level. Enrollment to phase II began in February 2019. 39% of planned patients have been enrolled as of January 2020. Clinical trial registry number: NCT03304080.

Citation Format: Krystal Pauline Cascetta, Poulikos Poulikakos, Charles Shapiro, Julie Fasano, Aarti Bhardwaj, Hanna Irie, Anupama Goel, Paula Klein, Meng Ru, Amy Tiersten. Multicenter, phase I/II trial of anastrozole, palbociclib, trastuzumab, and pertuzumab in HR-positive, HER2-positive metastatic breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT262.

Results of a phase Ib study investigating durvalumab in combination with eribulin in patients with metastatic HER2-negative breast cancer and recurrent ovarian cancer

e15120

Background: The release of tumor-associated antigens with cytotoxic chemotherapy treatment may enhance the response to immune checkpoint blockade. Eribulin is a novel microtubule inhibitor with proven overall survival (OS) benefit in metastatic breast cancer (MBC), which may also enhance intratumoral vascular remodeling. Durvalumab, a humanized monoclonal antibody, targets the programmed cell death ligand-1 (PD-L1) receptor. This study sought to determine the recommended phase II dose (RP2D) of eribulin in combination with durvalumab, as well as the safety and preliminary anti-tumor activity of the combination in patients with previously treated HER2-negative MBC and recurrent ovarian cancer (ROC). Methods: Cohorts of 3-6 patients with HER2-negative MBC and ROC were treated in a modified 3+3 design. Eligible patients received escalating doses of eribulin (1.1mg/m2 or 1.4 mg/m2 IV on day 1 and day 8) with durvalumab (1.12g IV on day 1) in 21-day cycles until dose-limiting toxicity (DLT), intolerable adverse events (AEs), disease progression, or other reasons for withdrawal. Primary endpoint: the rate of dose limiting toxicities (DLTs) during cycle 1 and 2 of therapy. Secondary endpoints: AE rate, Objective Response Rate (ORR), progression-free survival (PFS), and OS. Results: Nine patients [median age 63 (37-77)] with median 4 prior therapies for advanced disease were treated: 5 patients with HER2-negative MBC and 4 patients with ROC. The RP2D of eribulin was 1.4mg/m2 in combination with durvalumab. There were no DLTs experienced during the first two cycles of therapy. The most common treatment-related AEs ( > 50%) were fatigue, neutropenia, decreased white blood cell count, anemia, AST and alkaline phosphatase elevation, hyperglycemia, and nausea; most were grade 1/2. There was one immune-related AE of grade ≥3 (hepatitis). Three patients discontinued study drug related to toxicity [neutropenia (n = 1), hepatic toxicity (n = 2)]. ORR was 55% (all partial response) and 4 additional patients experienced stable disease; all MBC patients experienced a response to therapy. Median PFS was 6.2 months. Median OS has not been reached. Conclusions: The combination of eribulin and durvalumab had a favorable AE profile in patients with previously treated HER2- MBC and ROC. The early anti-tumor activity observed in this study suggests that further investigation of this combination is warranted. Clinical trial information: NCT03430518 .

Abstract P3-11-03: Pilot neoadjuvant study of niraparib in HER2-negative, BRCA-mutated resectable breast cancer

Background: Niraparib is a selective poly(ADP-ribose) polymerase 1/2 inhibitor that has demonstrated antitumor activity in advanced triple-negative breast cancer (TNBC) in combination with a programmed cell death 1 inhibitor, with the greatest clinical activity seen in tumors with breast cancer susceptibility gene (BRCA) mutations. Pharmacologically, niraparib has demonstrated a wide volume of distribution and high cell membrane permeability. In breast and ovarian cancer xenograft mouse models, niraparib achieved tumor exposures that were 3.3 times greater than plasma exposure. The objective of this study is to evaluate the antitumor activity of single-agent niraparib in the neoadjuvant treatment of patients with localized, human epidermal growth factor receptor 2 (HER2)-negative, BRCA-mutated breast cancer. The relative concentration of niraparib in tumor versus plasma was also assessed. Methods: Eligible patients were ≥18 years old, with HER2-negative, BRCA-mutated (germline or somatic) resectable breast cancer with a tumor size of ≥1 cm who had not received prior treatment for the current malignancy. Patients received niraparib 200 mg once daily for 2 months. At the end of 2 months, at their treating physician’s discretion, patients proceeded directly to surgery, received additional cycles of niraparib (maximum of 6 months), or received neoadjuvant chemotherapy. The primary endpoint was tumor response rate measured by magnetic resonance imaging (MRI) after 2 months of treatment. Response was defined as a ≥30% reduction in tumor volume from baseline. Secondary endpoints included tumor response rate measured by ultrasound, quantified percent change in tumor volume measured by MRI or ultrasound, pathological complete response, and safety and tolerability. Additionally, niraparib concentrations were measured in tumor and plasma samples using qualified liquid chromatography-tandem mass spectrometry. Results: Twenty-one patients were enrolled. As of June 2019, 18 patients had both an MRI and ultrasound scan at the end of month 2 and were evaluable for response. Ten patients are currently on treatment. The median age of patients was 43 years (range, 21-73). Fourteen patients had a BRCA1 mutation, 6 patients had a BRCA2 mutation, and 1 patient had both. Fifteen patients had TNBC, and 6 patients had hormone receptor-positive disease. All 18 response-evaluable patients had a clinical response after 2 months of treatment by at least one imaging modality; no patient experienced disease progression. Tumor response rate measured by MRI after 2 months of treatment was 89% (n/N = 16/18). Results measured by ultrasound were similar, with a 94% response rate at cycle 2 (n/N = 17/18). The median percent decrease in tumor volume after 2 months of treatment was 88% (range, 26-100%) and 89% (range, 23-100%) as measured by MRI and ultrasound, respectively. In the 5 samples measured thus far, niraparib concentrations in tumor biopsies after 2 months of treatment ranged from approximately 4-131-fold higher than those in corresponding plasma samples. Efficacy and tumor concentration data for all patients will be presented at the meeting. The most common (≥10%) drug-related treatment-emergent adverse events (TEAEs) of any grade were nausea, fatigue, anemia, insomnia, and decreased appetite. The only drug-related grade ≥3 toxicity in ≥10% of patients was anemia (3 patients). Three patients had a dose reduction due to a TEAE; no patient discontinued treatment due to a TEAE. Conclusion: Niraparib was well tolerated and showed promising antitumor activity in the neoadjuvant treatment of patients with localized HER2-negative, BRCA-mutated breast cancer. Niraparib achieved 4-131-fold higher concentrations in tumor than in plasma. Clinical trial information: NCT03329937. Funding: TESARO: A GSK Company (Waltham, MA, USA) sponsored the study.

Citation Format: Hyo Han, Minetta C Liu, Erika Hamilton, Hanna Irie, Cesar A Santa-Maria, James Reeves, Andre Liem, Adrianna Milillo Naraine, Julie Nangia, David Page, Meghan Duncan, Ming Shan, Yongqiang Tang, Julie R Graham, Leif W Ellisen, Steven Isakoff, Laura Spring. Pilot neoadjuvant study of niraparib in HER2-negative, BRCA-mutated resectable breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-11-03.

A multicentered randomized phase II comparison of single-agent carboplatin versus the combination of carboplatin and everolimus for the treatment of advanced triple-negative breast cancer

TPS1109

Background: Triple negative breast cancer (TNBC) is an aggressive disease with unmet clinical needs. Women with TNBC tend to be younger and demonstrate early recurrence, higher histological grade, higher rate of visceral metastasis and increased mortality rates when compared to hormone positive breast cancer. Prognosis for metastatic TNBC is especially poor. Due to lack of targeted therapies, there is no standard treatment of choice for triple negative breast cancer and chemotherapy remains the accepted standard. Many chemotherapeutic agents have been reported to have clinical activity either as single agent or in combination. Seventy percent of breast cancers with BRCA-1 germline mutations are triple negative, which suggests a shared carcinogenic pathway between them. In preoperative and metastatic settings, both TNBC and BRCA-1 associated breast cancers are particularly sensitive to DNA cross-linking agents such as platinum compounds due to defective DNA repair by homologous recombination. The recent TNT trial showed in patients with triple negative metastatic or recurrent locally advanced breast cancer with BRCA1/2 mutations, carboplatin resulted in a significantly higher overall response rate versus docetaxel (68% versus 33.3%; p=0.03). Triple negative breast cancers are associated with a high frequency of PTEN loss, which leads to mTOR activation. Moreover, it has been reported that mTOR activation may confer resistance to platinum agents such as cisplatin, a phenomenon that may be reversible by the addition of an mTOR inhibitor such as everolimus. There are reports of synergy between mTOR inhibitors and platinum compounds in pre-clinical and clinical data. Methods: We have opened a multi-centered randomized phase II trial comparing carboplatin AUC 4 q 3 weeks vs carboplatin AUC 4 q 3 weeks combined with daily 5 mg everolimus. 41 of planned 72 patients from the Mount Sinai Health System have been enrolled and are randomized in a 2:1 allocation. The primary objective is to compare progression-free survival in patients treated with carboplatin+everolimus to patients treated with carboplatin alone. Patients may have had up to 3 prior regimens for metastatic disease. Exploratory biomarker assessment is being done to identify markers of response. Clinical trial information: NCT02531932.

A phase I study of the safety and immunogenicity of a multi-peptide personalized genomic vaccine in the adjuvant treatment of solid tumors and hematological malignancies

e14307

Background: Mutation-derived tumor antigens (MTAs) arise as a direct result of somatic variations that occur during carcinogenesis and can be characterized via genetic sequencing and used to identify MTAs. We developed a platform for a fully-personalized MTA-based vaccine in the adjuvant treatment of solid and hematological malignancies. Methods: This is a single-arm, open label, proof-of-concept phase I study designed to test the safety and immunogenicity of Personalized Genomic Vaccine 001 (PGV001) that targets up to 10 predicted personal tumor neoantigens based on patient’s HLA profile (ClinicalTrials.gov: NCT02721043). Results: Patients who completed vaccination with PGV001_002 (head and neck squamous cell cancer) received 10 doses of vaccine comprising 10 long peptides (LP) combined with poly-ICLC (toll-like receptor-3 agonist) intradermally. Vaccine-induced T-cell responses were determined at weeks 0 and 27 (before and after treatment, respectively), ex vivo by interferon (IFN)-g enzyme-linked immunospot assay and after expansion by intracellular cytokine staining. Overlapping 15-mer peptides (OLPs) spanning the entirety of each LP and 9-10-mer peptides corresponding to each predicted class I epitope (Min) were pooled. Ex vivo responses to these peptide pools were undetectable at week 0 but were evident at week 27 against 2 OLPs out of 10 (20%) and in 5 Min out of 10 (50%). After in vitro expansion, neoantigen-specific CD4+ and CD8+ T-cell responses were found in 5 out of 10 pooled peptides (50%). 7 out of 10 (70%) epitopes elicited polyfunctional T-cell responses (secretion of INF-g, TNF-a, and/or IL-2) from either CD4+ or CD8+ T cells. Conclusions: The PGV001 vaccine in our first patient showed both safety and immunogenicity, eliciting CD4+ and CD8+ responses to the vaccine peptides. As we enroll additional patients in this clinical trial, and perform deeper phenotyping of their tumor-reactive T cells, we will learn the determinants necessary for the successful generation of MTA-based vaccines, while informing future immunotherapeutic approaches and rational combinations. Clinical trial information: NCT02721043.

Abstract OT3-03-01: Open-label, single-arm study evaluating the antitumor activity and safety of niraparib as neoadjuvant treatment in patients with localized, HER2-negative, BRCA-mutant breast cancer

Background: Neoadjuvant chemotherapy is administered to patients with operable breast cancer to downstage the tumor to allow for less extensive surgery and to provide prognostic information about drug efficacy and risk of disease recurrence. Patients who achieve a pathological complete response (pCR) following neoadjuvant treatment have a more favorable outcome than patients with residual invasive disease. Single-agent poly(ADP-ribose) polymerase (PARP) inhibitors have clinical efficacy in BRCA-mutated breast cancer. Niraparib, a potent and selective PARP1/2 inhibitor, is approved for maintenance treatment of patients with recurrent ovarian cancer and has demonstrated strong antitumor activity in in vivo studies with BRCA1-mutant breast cancer. The objective of this study is to evaluate the antitumor activity of single-agent niraparib in the neoadjuvant treatment of patients with localized, human epidermal growth factor receptor 2 (HER2)-negative, BRCAmut breast cancer.

Trial Design: This is an open-label, single-arm pilot study with a target enrollment of 20 evaluable patients. Eligible patients are those ≥18 years old with histologically-confirmed HER2-negative localized breast cancer and either a BRCA1 or BRCA2 mutation (germline or somatic) and no prior anti-cancer therapies for the current malignancy. Patients will receive 200 mg of oral niraparib once daily for 2 months, after which they may either proceed directly to surgery or receive chemotherapy at the discretion of the physician. The primary endpoint is tumor response rate based on the change in tumor volume as measured by breast MRI after 2 months of treatment with niraparib; a response is defined as ≥30% reduction of tumor volume from baseline. Secondary endpoints include pCR rate, tumor response rate based on the change in tumor volume as measured by breast ultrasound, and safety and tolerability. Data will be summarized in a descriptive nature by frequency distributions (number and percentage of patients) for categorical variables and by the mean, median, and standard deviation for continuous variables. Tumor response rate will be tabulated together with its 95% binomial exact confidence interval.

Funding: TESARO, Inc., Waltham, MA, USA sponsored the study.

Citation Format: Han H, Hamilton E, Irie H, Isakoff S, Jelovac D, Liem A, Liu MC, Milillo A, Nangia J, Page D, Reeves J, Santa-Maria C, Duncan M, Graham JR, Chen J, Dezube BJ, Spring L. Open-label, single-arm study evaluating the antitumor activity and safety of niraparib as neoadjuvant treatment in patients with localized, HER2-negative, BRCA-mutant breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-03-01.

Abstract A005: A phase I study of the safety and immunogenicity of a multipeptide personalized genomic vaccine in the adjuvant treatment of solid cancers

Introduction: Mutation-derived tumor antigens (MTAs) arise as a direct result of somatic variations, including nucleotide substitutions, insertions, and deletions that occur during carcinogenesis. These somatic variations can be characterized via genetic sequencing and used to identify MTAs. We developed a platform for a fully-personalized MTA-based vaccine in the adjuvant treatment of solid and hematologic malignanicies. Methods: This is a single-arm, open label, proof-of-concept phase I study designed to test the safety and immunogenicity of Personalized Genomic Vaccine 001 (PGV001) that targets up to 10 predicted personal tumor neoantigens. The single-center study will enroll 20 eligible subjects with histologic diagnosis of solid and hematologic malignancies. Subjects must have no measurable disease at time of first vaccine administration, and 5-year disease recurrence risk of > 30%. Toxicity will be defined by CTCAE v5.0. Blood samples will be collected at various time points for immune response monitoring. Each patient’s vaccine peptides are selected by identifying somatic mutations from comparison of tumor and normal exome sequencing data, phasing somatic variants with co-occurring germline variants using tumor RNA sequencing data, and ranking mutated peptide sequences ”Openvax pipeline.” The process for determining somatic variants hews closely to the Broad Institute’s “Best Practices” for cancer SNVs and indels. The phasing of somatic and germline variants is implemented in a custom bioinformatics tool called Isovar. Mutated protein sequences containing phased variants are ranked according to two criteria: expression of the mutant allele in tumor RNA and aggregated predicted affinity to the patient’s Class I MHCs. Both quantities are normalized and multiplied together to create single ranked ordering of the candidate mutant sequences. Results: PGV001_002 (head and neck squamous cell cancer), who has completed vaccination, received 10 doses of vaccine comprising 10 long peptides (25 amino acid length) combined with poly-ICLC (toll-like receptor-3 agonist) intradermally. Vaccine-induced blood T-cell responses were determined, at weeks 0 (before-treatment) and 27 (after-treatment), ex vivo by interferon (IFN)-g enzyme-linked immunospot (ELISPOT) assay and after in vitro expansion by intracellular cytokine staining (ICS). Overlapping 15-16-mer assays peptides (OLPs) spanning the entirety of each ILP and 9-10-mer peptides corresponding to each predicted class I epitope (Min) were pooled and used to monitor immunogenicity. Ex vivo responses to these peptide pools were undetectable at week 0 but were evident at week 27 against 2 OLPs out of 10 (20%) and in 5 Min out of 10 (50%). After in vitro expansion, neoantigen-specific CD4+ and CD8+ T-cell responses were found in 5 out of 10 pooled peptides (50%). 7 out of 10 (70%) epitopes elicited polyfunctional T-cell responses (secretion of INF-α, TNF-α, and/or IL-2) from either CD4+ or CD8+ T-cells. Conclusion: To identify which predicted epitopes within the peptides pools stimulated the T-cell responses, we deconvoluted all the pools by either ex vivo and in vitro expansion. Ex vivo IFN-α production was detected in 1 (15-mer) peptide out of 15 (6.7%) and in 4 (9-10-mer) peptides out of 22 (18.2%). After expansion with single peptides, of 22 (9-10-mer) peptides tested, CD8+ T-cells were reactive against 13 peptides (59%), while CD4+ responses were seen in response to 11 of 15 (15-16-mer) peptides tested. Both CD4+ and CD8+ T-cell responses were polyfunctional. The PGV001 vaccine in our first patient showed both safety and immunogenicity, eliciting both CD4+ and CD8+ responses to the vaccine peptides. As we are enrolling additional patients, the information learned from this clinical trial will instruct the next generation of MTA-based vaccines, future development of immunotherapeutic approaches and rational combinations.

Citation Format: Ana B. Blazquez, Alex Rubinsteyn, Julia Kodysh, John P. Finnigan, Thomas Marron, Rachel L. Sabado, Marcia Meseck, Timothy J. O'Donnell, Jeffrey Hammerbacher, Michael Donovan, John Holt, Milind Mahajan, John Mandeli, Krysztof Misiukiewicz, Eric M. Genden, Brett A. Milles, Hooman Khorasani, Peter R. Dottino, Hanna Irie, Amy B. Tiersten, Elisa R. Port, Andrea S. Wolf, Hern J. Cho, Ashutosh Tewari, Samir S. Parekh, Sujit Nair, Matthew D. Galsky, William K. Oh, Sacha Gnjatic, Eric E. Schadt, Phillip A. Friedlander, Nina Bhardwaj. A phase I study of the safety and immunogenicity of a multipeptide personalized genomic vaccine in the adjuvant treatment of solid cancers [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A005.

EMUDRA: Ensemble of Multiple Drug Repositioning Approaches to improve prediction accuracy

Motivation

Availability of large-scale genomic, epigenetic and proteomic data in complex diseases makes it possible to objectively and comprehensively identify the therapeutic targets that can lead to new therapies. The Connectivity Map has been widely used to explore novel indications of existing drugs. However, the prediction accuracy of the existing methods, such as Kolmogorov-Smirnov statistic remains low. Here we present a novel high-performance drug repositioning approach that improves over the state-of-the-art methods.

Results

We first designed an expression weighted cosine (EWCos) method to minimize the influence of the uninformative expression changes and then developed an ensemble approach termed ensemble of multiple drug repositioning approaches (EMUDRA) to integrate EWCos and three existing state-of-the-art methods. EMUDRA significantly outperformed individual drug repositioning methods when applied to simulated and independent evaluation datasets. We predicted using EMUDRA and experimentally validated an antibiotic rifabutin as an inhibitor of cell growth in triple negative breast cancer. EMUDRA can identify drugs that more effectively target disease gene signatures and will thus be a useful tool for identifying novel therapies for complex diseases and predicting new indications for existing drugs.

Availability and implementation

The EMUDRA R package is available at doi: 10.7303/syn11510888.

Supplementary information

Supplementary data are available at Bioinformatics online.

Serial CTC/cfDNA assessment for the identification of pathogenic mutations in patients with breast cancer

e23070

Background: Serial liquid biopsy assessment provides a unique platform for detecting existing and / or emergent resistance mutations; it may be particularly beneficial when patients begin to progress on otherwise effective therapy. We aimed to determine the utility of such an approach for detection of tumor genetic alterations at multiple points during the clinical course of patients diagnosed with breast cancer. Methods: Twenty patients diagnosed with stage I-IV breast cancer (50% with triple negative disease) receiving treatment at the Dubin Center of Mount Sinai were consented for serial CTC/cfDNA collections between October 2015 and November 2016. Circulating tumor cell (CTC)/cell-free DNA (cfDNA) were isolated using Cynvenio’s Liquid Biopsy platform and sequenced utilizing the Hotspot/Oncomine panels. DNA from corresponding patient tumors, when available, was also sequenced. Results: 25% of patients had at least one known pathogenic mutation detected in either cfDNA or CTC DNA in at least one collection; all patients had stage IV disease at collection. Pathogenic mutations detected were in p53 (15%), PIK3CA (10%) and Smad4 (5%). For those patients with available tumor tissue, the same pathogenic mutation was detected in the primary tumor. Mutations were more often detected in cfDNA rather than CTC DNA. Finally, known pathogenic mutations were more consistently detected in serial collections with clinical disease progression and resistance to treatment. Conclusions: Pathogenic mutations were identified in 25% of patients, more frequently in cfDNA and not in every collected sample, supporting serial collection studies to monitor response. Presence of same pathogenic mutations in the patient’s primary tumor suggest a role for surveillance in early stage, as well as advanced disease.

A phase I study of the safety and immunogenicity of a multipeptide personalized genomic vaccine in the adjuvant treatment of solid cancers

TPS3114

Background: Mutation-derived tumor antigens (MTAs) arise as a direct result of somatic variations, including nucleotide substitutions, insertions, and deletions that occur during carcinogenesis. These somatic variations can be characterized via genetic sequencing and used to identify MTAs. We propose a platform for a fully-personalized MTA-based vaccine in the adjuvant treatment of solid tumors. Methods: This clinical trial is a single-arm, open label, proof-of-concept phase I study designed to test the safety and immunogenicity of the Personalized Genomic Vaccine 001 (PGV001). The single-center study will enroll 20 eligible subjects with histological diagnosis of the following tumor types: (a) head and neck squamous cell cancer, (b) non-small cell lung cancer, (c) ductal or lobular breast cancer, (d) serous carcinoma of the ovary, uterine adnexa, (e) urothelial carcinoma of renal pelvis or bladder, (f) cutaneous squamous cell cancer. Subjects must have no measurable disease at time of first vaccine administration, and 5-year disease recurrence risk of > 30%. Patients will receive 10 doses of PGV001 as well as 10 doses of poly-ICLC (toll-like receptor-3 agonist, vaccine adjuvant), administered 1 day after PGV001 vaccination. Toxicity (endpoint 1) will be defined by Common Terminology Criteria for Adverse Events v5.0. Blood samples will be collected at various time points for immune response monitoring of MTA-specific humoral and cellular immune responses. For each patient, immunogenicity (endpoint 2) will be defined as an epitope-specific T cell response, detectable in peripheral blood samples after PGV001 vaccination. The change in the frequency of vaccine-induced epitope-specific T lymphocyte populations post-vaccination relative to baseline will be determined using mixed effects linear regression modeling. Conclusions: Our clinical trial will test for the first time the safety and immunogenicity of PGV001 in patients with multiple solid cancers. The information learned from this clinical trial will instruct the next generation of MTA-based vaccines, future development of immunotherapeutic approaches and rational combinations. Clinical trial information: NCT02721043.

Quantum Hall effect in epitaxial graphene with permanent magnets

We have observed the well-kown quantum Hall effect (QHE) in epitaxial graphene grown on silicon carbide (SiC) by using, for the first time, only commercial NdFeB permanent magnets at low temperature. The relatively large and homogeneous magnetic field generated by the magnets, together with the high quality of the epitaxial graphene films, enables the formation of well-developed quantum Hall states at Landau level filling factors v = ±2, commonly observed with superconducting electro-magnets. Furthermore, the chirality of the QHE edge channels can be changed by a top gate. These results demonstrate that basic QHE physics are experimentally accessible in graphene for a fraction of the price of conventional setups using superconducting magnets, which greatly increases the potential of the QHE in graphene for research and applications.

Abstract P3-06-31: Patient-derived xenografts accurately predict patient response in breast cancer patients

PURPOSE/OBJECTIVES: A growing body of evidence demonstrates that patient-derived xenografts (PDXs) represent living tumor models that accurately reflect the biology of the primary patient tumor. More importantly, we have previously shown that PDX models show responses to therapeutic agents that are concordant with patient clinical response and can be used to direct personalized cancer treatments (Stebbing, 2014). Here we report the ability of PDX models to predict for patient response to drug treatment in a cohort of breast cancer patients.

MATERIALS/METHODS: Tumors were resected from patients with either primary or metastatic breast cancer and implanted into immunodeficient mice to establish PDX models. Successfully engrafted PDX models were expanded and randomized for drug sensitivity testing. Tumor growth inhibition and tumor regression were captured and results were correlated with a patient’s clinical response. In some cases, PDX results were used to personalize cancer treatment and some patients used PDX-directed treatments over multiple lines of therapy.

RESULTS: A total of 42 tumors from 40 patients were implanted resulting in 21 successfully engrafted PDX models (50% engraftment rate). Notably, engraftment rates were much higher for patients with triple negative breast cancer (TNBC) and resulted in 7 successful PDX models from 8 TNBC patients (87.5% engraftment rate). Drug sensitivity testing was offered to patients with established PDX models. Drugs and drug combinations tested included standard and nonstandard chemotherapy as well as biologics. At that time of this publication, 4 patients (3 TNBC and 1 HER2+) with completed drug sensitivity tests also had clinical data available resulting in 7 clinical correlations; 4 retrospective and 3 prospective. In all 7 cases, the PDX model accurately predicted patient clinical response demonstrating an accuracy of 100%. Five of the drug tests predicted drug sensitivity and 2 tests predicted resistance, indicating the potential of the PDX platform to predict for both sensitivity and resistance to therapy. The 3 prospective correlations resulted in concordant clinical benefit in 2 patients for duration greater than 6 months each.

CONCLUSIONS: These data support the use of the personalized PDX model as a platform for therapeutic decision making that can guide treatment for patients with breast cancer. A prospective clinical trial in TNBC is currently underway.

Citation Format: Lisa Stow, Amanda Katz, Hanna Irie, Elisa Port, Justin Stebbing, Daniel Ciznadija, Angela Davies, Keren Paz. Patient-derived xenografts accurately predict patient response in breast cancer patients [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-06-31.

Polymerization of room-temperature ionic liquid monomers by electron beam irradiation with the aim of fabricating three-dimensional micropolymer/nanopolymer structures

A novel method for fabricating microsized and nanosized polymer structures from a room-temperature ionic liquid (RTIL) on a Si substrate was developed by the patterned irradiation of an electron beam (EB). An extremely low vapor pressure of the RTIL, 1-allyl-3-ethylimidazolium bis((trifluoromethane)sulfonyl)amide, allows it to be introduced into the high-vacuum chamber of an electron beam apparatus to conduct a radiation-induced polymerization in the nanoregion. We prepared various three-dimensional (3D) micro/nanopolymer structures having high aspect ratios of up to 5 with a resolution of sub-100 nm. In addition, the effects of the irradiation dose and beam current on the physicochemical properties of the deposited polymers were investigated by recording the FT-IR spectra and Young's modulus. Interestingly, the overall shapes of the obtained structures were different from those prepared in our recent study using a focused ion beam (FIB) even if the samples were irradiated in a similar manner. This may be due to the different transmission between the two types of beams as discussed on the basis of the theoretical calculations of the quantum beam trajectories. Perceptions obtained in this study provide facile preparation procedures for the micro/nanostructures.

Abstract 363: Planar filtered gene regulatory networks in breast cancer

Gene co-expression network analysis has been shown to be effective in identifying functional co-expressed gene modules associated with complex human diseases such as cancer, Alzheimers’ disease, obesity and diabetes. However, existing techniques to construct co-expression networks require some critical prior information such as predefined number of modules to be detected and numerical thresholds for defining coexpression/interaction, or do not naturally reproduce the hallmarks of complex systems such as scale-free degree distribution of small-worldness). In order to mitigate these problems as whole or in part, we have developed a novel co-expression network analysis approach, Planar Filtered Network Analysis (PFNA). PFNA utilizes a graph filtering technique to identify “true” interactions by means of embedding candidate interactions on a topological sphere(2, 3). Planar Filtered Networks (PFN) are naturally scale-free, small-world, and are comprised of a number of highly co-expressed gene modules). Furthermore, PFNA allows differential topology analysis of networks from different disease states based on centrality and peripherality metrics).

We performed PFNA on the breast cancer data from The Cancer Genome Atlas (TCGA), and identified a number of novel gene modules associated with overall survival of the whole cohort or patient subgroups defined by receptor status (ER, PR, HER2) and PAM50 biomarkers(6). PFNA uncovers not only gene modules enriched for genes in well-known cancer pathways such as cell-cycle and immune response, but also novel modules that prognostically stratify patients with triple negative or basal breast cancers. Notably, several modules involved in G-protein coupled receptor signaling, protocadherin α and β pathways are highly predictive of survival for patients with triple negative disease. Furthermore, the differential topology analysis reveals that breast cancer biomarkers such as PAM50 and poor prognosis gene sets developed by van’t Veer et al(7) are more central in the tumor network than the one based on the matched adjacent normal breast tissues.

In summary, PFNA reveals a number of novel high-level molecular features of the highly heterogeneous breast cancer. This novel network analysis method provides a set of unsupervised tools to objectively identify subnetworks that are associated with complex diseases such as breast cancer.

1. R. Albert, A. L. Barabasi. Rev Mod Phys 74, 47.

2. M.Tumminello, T. Aste, T. Di Matteo, R. N. Mantegna. Proc Natl Acad Sci U S A 102,10421.

3. T.Aste, T. Di Matteo, S. T. Hyde. Physica A 346, 20.

4. W.M. Song, T. Di Matteo, T. Aste. Phys RevE Stat Nonlin Soft Matter Phys 85,046115.

5. F.Pozzi, T. Di Matteo, T. Aste. Adv Complex Syst 11, 927.

6. J. S. Parker et al.. Journal of clinical oncology: 27, 1160.

7. L.J. van 't Veer et al.. Nature 415, 530.

Citation Format: Won-min Song, Tao Huang, Seungyeul Yoo, EunJee Lee, Yongzhong Zhao, Li Wang, Zhidong Tu, Xudong Dai, Hanna Irie, Jun Zhu, Bin Zhang. Planar filtered gene regulatory networks in breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 363. doi:10.1158/1538-7445.AM2014-363

Protein tyrosine kinase 6 (PTK6, BRK) amplification in HER2+ breast cancer as a mechanism of HER2 resistance

11021

Background: PTK6 gene on chromosome 20q13 encodes the intracellular non-receptor tyrosine kinase. Studies in vivo and in vitro revealed a role for PTK6 in cell proliferation and survival, particularly in HER2+ breast cancer cells suggesting that PTK6 may associate with the HER2 pathway and confer resistance to HER2-targeted therapy. PTK6 protein is frequently overexpressed in breast cancer, however, the mechanism(s) underlying PTK6 overexpression and its role in cancer remains unclear. To address this problem, we analyzed the frequency of PTK6 gene copy number variation (CNV) and expression in association with breast cancer subtypes. Methods: Retrospectiveparaffinsamples of invasive tumor and normal epithelium, and matching DCIS and metastases were mounted on TMA. PTK6 CNV was determined using PTK6:CEP20 FISH assay. Tumor subtypes were defined using the five-marker IHC classifier. The correlation between PTK6 CNV and mRNA expression and association of both with the intrinsic PAM50 tumor subtype were studied using TCGA database (547 cases) and publicly available seven breast cancer data sets (1005 cases). Data were normalized, gene median centered and standardized for the purpose of the study. Results: By FISH, 20% of 41 invasive tumors carried PTK6 CNV: amplification (10%) and gene polysomy (10%). The proportion of PTK6 amplified cases differed by subtype, with the largest proportion in HER2-enriched (17%) and LumB (14%). Strikingly, amplified invasive cases also showed amplification in matching DCIS and metastases. Analysis of the public datasets confirmed the frequent PTK6 amplification in breast cancer. Both low and high levels of amplification were detected with the largest proportion in HER2+ tumors (HER2-enriched and LumB; p=2.05e-26). None of the basal-like tumors showed high levels of PTK6 amplification. A high correlation between PTK6 gene copies and mRNA expression was observed (p=1.13e-08). Conclusions: PTK6 gene is amplified early in breast cancer progression, particularly in HER2+ tumors. Further studies on PTK6 biology may help clinicians to understand its potential role in HER2 resistance. Supported by BREAST CANCER SPORE, NCI K12CA139160 and CTSA-ITM CS UL1 RR024999.

Hemodynamic studies of intracranial dural arteriovenous fistulas using arterial spin-labeling MR imaging

Arterial spin-labeling (ASL) magnetic resonance imaging (MRI) enables non-invasive acquisition of the brain perfusion information in cerebrovascular disease. We investigated hemodynamic changes in intracranial dural arteriovenous fistulas (DAVFs) using ASL-MRI. ASL-MRI by a Q2TIPS sequence on a 3.0-Tesla MRI was performed for three patients with Cognard's IIa+b type of DAVFs before and after treatment. Perfusion images obtained by ASL-MRI (ASL images) before treatment were visually compared with those by single-photon emission computed tomography images (SPECT images). Increasing rates of temporal changes of regional perfusion values in ASL images (ASL values) before and after treatment were also calculated. In all three patients, ASL images before treatment demonstrated high perfusion in regions around the shunting areas, where normal or low perfusion were detected on SPECT images; thus, ASL images might have demonstrated the abundant arterial shunting flow via the fistulas. On days eight to 20 after treatment, ASL values around the shunt areas remained the same or decreased, and those in the regions other than the shunt areas increased in all three patients. This might have been due to a combination of the following: a decrease in shunt flow volume, an amelioration of venous congestion, and a sustained an upward shift in the autoregulation of the brain perfusion pressure. All regional ASL values decreased on days 112 and 120 after treatment in two patients, which possibly reflects a reduction in the upward shift in autoregulation. ASL-MRI might be useful for identifying the hemodynamic behavior of DAVFs before and after treatment.

Gene expression-based pharmacodynamic biomarkers: the beginning of a new era in biomarker-driven anti-tumor drug development

Pharmacodynamic (PD) biomarkers play a pivotal role in anti-tumor drug development as a biochemical measurement to estimate the level of drug interaction with the target, or to assess the downstream impact of its interaction with the target. Although immunohistochemistry (IHC)-based protein biomarkers have been conventionally used as PD biomarkers, gene expression-based PD biomarkers have recently emerged as quantitative biomarkers. This review introduces examples of gene expression-based mRNA biomarkers that have been validated in preclinical or clinical studies of several anti-tumor agents including HDAC, mTOR, and B-RAF inhibitors. The measurement of PD biomarker levels in tumors has proven to be ideal; however, in clinical studies, easily accessible surrogate tissues have been used for analysis. In the present review, we also discuss the advantages and disadvantages in using surrogate tissues, such as peripheral blood mononuclear cells (PBMCs), skin tissue, and circulating tumor cells, in the assessment of PD biomarkers. PD biomarkers are generally classified into two categories: 1) target engagement biomarkers and 2) early efficacy biomarkers. This classification depends on their respective distance from target intervention. The strategies used to identify and distinguish between these two types of PD biomarkers via expression profiling are also discussed. Finally, we propose two novel approaches for PD marker identification. One approach utilizes mRNA expression profiling of tumors prior to drug treatment rather than post-treatment samples. The second method involves the application of microRNA expression profiles to determine PD effects. In conclusion, the recent advances in mRNA and microRNA profiling and the identification of gene expression-based PD biomarkers may aid investigators to drive drug development through the establishment of quantitative PD effects.

Hepatic falciform ligament artery in patients with chronic liver diseases: detection on computed tomography hepatic arteriography

BACKGROUND

The detection rate of hepatic falciform ligament artery (FLA) has been reported as ranging from 2-25%. The rate of FLA on laparotomy, however, is reported to be higher, at 68%.

PURPOSE

To compare the detection rate of FLA on computed tomography hepatic arteriography (CTHA) with that on angiography and dynamic CT, and to clarify the clinical significance of FLA in patients with chronic liver disease.

MATERIAL AND METHODS

126 consecutive patients underwent CTHA angiography and dynamic CT to evaluate suspected liver tumors. Liver function was classified as follows: normal, n=5; Child-Pugh class A, n=94; B, n=21; and C, n=6. All CT images were obtained using multidetector (MDCT) scanners (Aquilion; Toshiba, Tokyo, Japan). For CTHA, CT images were obtained during contrast material injection through the left hepatic, proper, or common hepatic artery. On CT, FLAs were retrospectively identified within the hepatic falciform ligament and the hepatic round ligament by the paging method on a workstation (TWS-5000; Toshiba, Tokyo, Japan). The detection rates were compared among the three modalities (hepatic arterial phase of dynamic CT, CTHA, and angiography). The calibers of FLA were also correlated with the hepatic function of the patients.

RESULTS

The detection rates of FLA by angiography, dynamic CT, and CTHA were 37% (47/126), 10% (13/126), and 77% (97/126), respectively. The calibers of FLA increased as the hepatic function deteriorated (P=0.001).

CONCLUSION

The detection rates of FLA with CTHA are far higher than those with angiography and dynamic CT. Careful interpretation with recognition of FLA on CTHA images is important, as inadvertent embolization or chemotherapeutic infusion of the FLA may result in supraumbilical skin rash.

Microcoil embolization through a downsized coaxial catheter system: an experimental study

BACKGROUND

Most of the recently developed microcatheters for abdominal angiography still have large diameters at their trailing ends, and thus cannot be used for microcoil embolization in combination with a 3-French (F) system.

PURPOSE

To evaluate the in vitro passage of microcoils through a newly developed 2-F microcatheter (Meister Cath Superselective Plus, MC6) that is compatible with a downsized coaxial catheter system (3-F system) in an experimental study.

MATERIAL AND METHODS

We evaluated the passage of microcoils through MC6 within a blood vessel model using the saline flush technique. Six types of microcoils and 17 size variations (maximal curled diameter 2-10 mm, total length 20-140 mm) were used. We evaluated the passage and post-deployment shape of the microcoils as well as the volume of saline required to flush them.

RESULTS

In the experimental study, all microcoils passed through the MC6 and deployed in a satisfactory manner without catheter occlusion. The mean volumes of saline required to flush the TORNADO (n=1), Reverse TORNADO (n=6), HILAL (n=1), Micronester (n=3), VortX (n=4), and C-Stopper Coil (n=2) were 0.7 ml, 0.58+/-0.20 ml, 0.5 ml, 0.57+/-0.058 ml, 3.5+/-1.5 ml, and 0.70+/-0.14 ml, respectively. There was a statistically significant difference in the mean volume of saline required between the VortX and Reverse TORNADO (P=0.029), and between the VortX and C-Stopper Coil (P=0.031). The VortX required the greatest volume of saline.

CONCLUSION

Microcoil embolization through a 3-F system appears to be feasible for the coils examined in this study.

Portal vein occlusion or stenosis in patients with hepatolithiasis: observation by multiphasic contrast-enhanced CT

AIMS

To analyze the dynamic findings of multiphasic contrast-enhanced CT in hepatolithiasis and to elucidate occlusive changes in portal veins and other associated abnormalities.

METHODS

This was a retrospective study of 25 selected patients with hepatolithiasis who underwent various imaging examinations, including multiphasic contrast-enhanced CT. The following CT findings were evaluated in each of 71 hepatic segments: visualization of a calculus; biliary dilation or focal hepatic atrophy of the affected segment; areas that were abnormally enhanced in the hepatic arterial phase; degrees (normal, stenosis, occlusion) of portal vein calibre; and linear delayed enhancement along the bile-duct walls, suggesting cholangitis.

RESULTS

On CT, calculi were depicted as a hyperdense structures in 61 of 71 segments (86%). Focal hepatic atrophy, which frequently accompanied CT findings suggesting compensatory hypertrophy of other segments, was seen in 50 of 71 segments (70%). Areas that were abnormally enhanced were recognized in 36 of 71 segments (51%). Stenosis or occlusion of portal venous branches was observed in 59 of 71 segments (83%), including 13 segments with occlusion. Findings indicating cholangitis were noted in 50 of 71 segments (70%). The degrees of portal vein calibre were significantly correlated with the presence of hepatic atrophy or cholangitis.

CONCLUSION

Hepatolithiasis is associated with significant rates of stenosis or occlusion of adjacent portal veins as well as hepatic parenchymal changes in the affected area. Chronic deterioration of portal flow may cause these morphological changes.

Antioxidant effect of MCI-186, a new Free-Radical scavenger, on ischemia-reperfusion injury in a rat hindlimb amputation model

BACKGROUND

A newly synthesized free-radical scavenger, MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-1), was recently approved in Japan for treating acute brain infarction. The purpose of this study was to investigate whether or not MCI-186 is effective in reducing ischemia-reperfusion injury in the extremities.

MATERIALS AND METHODS

Warm ischemia was sustained for 4 hours. The animals were divided into 4 groups: (1) sham group, (2) control group (saline injection), (3) MCI group (MCI-186 injection), and (4) EPC group (EPC-K1 [(l-ascorbic acid 2-[3,4-dihydro-2, 5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl hydrogen phosphate] potassium salt], a hydroxyl-radical scavenger, injection). Wet and dry (W/D) weights of the gastrocnemius and tibialis anterior muscles, muscle contractile function, and serum levels of creatine phosphokinase (CPK), lactate dehydrogenase (LDH), glutamic oxaloacetic transminase (GOT), and mitochondrial glutamic oxaloacetic transminase (GOT-m) were measured after 24 h of reperfusion. The cytotoxic aldehydes malondialdehyde and 4-hydroxy-2-nonenal as indices of lipid peroxidation (LPO), and neutrophil-specific enzyme myeloperoxidase (MPO) as an index of neutrophil infiltration, were measured in the gastrocnemius muscle.

RESULTS

Contractile functions in the MCI and EPC groups were significantly better than in the control group. In the tibialis anterior muscle, the contractile function was better in the MCI group than in the EPC group. W/D ratios and serum levels of CPK, LDH, GOT, and GOT-m were lower in the sham and MCI groups than in the control group. Levels of LPO and MPO activity were significantly lower in the MCI and EPC groups than in the control group. Histological findings demonstrated that inflammatory tissue reactions rarely occurred in the MCI group.

CONCLUSION

MCI-186 is effective in preventing ischemia-reperfusion injury in extremities. MCI-186 seems to have promise as a therapeutic agent, because it prevents ischemia-reperfusion injury even in the tibialis anterior muscle, which contains fast-twitch glycolytic fibers, known to be very susceptible to ischemic insult.

Liver lesions of visceral larva migrans due to Ascaris suum infection:

The purpose of this study was to analyze computed tomographic (CT) findings of hepatic lesions due to Ascaris suum infection. CT of the liver in three patients, all of whom had immunoserologically confirmed A. suum infection, were retrospectively reviewed. Twenty-five lesions were identified in total. Two radiologists analyzed CT findings in a consensus fashion, with particular interest in the margin, shape, and location of the lesions. Hepatic lesions were ill-defined (22 of 25), small (3-35 mm; average, 11 mm), and nodular (18 of 25) or wedge (three of 25) in shape. Most were located in periportal (16 of 25) or subcapsular (six of 25) regions. Hepatic nodules due to visceral larva migrans of A. suum were located mainly in periportal or subcapsular regions, which may represent periportal eosinophilic granuloma, its pathologic feature. The results were considered to represent the pathophysiology of this entity.

Bilateral ovarian leiomyomas: CT and MRI features

We recently treated a 21-year-old woman with leiomyomas arising from the bilateral ovaries, a very rare condition. On magnetic resonance imaging, more than half of the left adnexal mass showed low signal intensity on T2-weighted images and good enhancement by gadolinium-DTPA, and the remaining part showed high signal intensity on T2-weighted images, so the lesions initially were diagnosed as ovarian fibromas or as thecomas with a certain degree of degeneration. Pathologic examination of the excised tumors proved that they were bilateral ovarian leiomyomas; in addition, the tumor from the left side showed hemorrhagic and myxoid changes with torsion of 180 degrees.

Gluteal muscular and sciatic nerve metastases in advanced urinary bladder carcinoma: case report

We present a case of gluteal muscular and sciatic nerve metastases from urinary bladder carcinoma. T2-weighted magnetic resonance images demonstrated diffuse swelling and an increase in the signal of the right gluteus maximus muscle without destruction of the original arrangement of muscular fibers. Further, remarkable thickening of the right sciatic nerve showing a relatively hypointense signal was detected. Postcontrast T1-weighted images showed strong enhancement of these structures. Fine-needle aspiration biopsy with ultrasonographic guidance confirmed metastatic carcinoma cells in the right gluteal muscle and the sciatic nerve. These radiologic findings may represent a rare pattern of metastasis from urinary bladder carcinoma.

Fat in liver metastasis from renal cell carcinoma detected by chemical shift MR imaging

A case with liver metastasis from papillary renal cell carcinoma (RCC) is presented, in which intratumoral fat was detected on dual-echo chemical shift magnetic resonance imaging (MRI). The preoperative chemical shift MR image of the primary RCC also suggested the presence of intratumoral fat. Liver metastasis from fat-containing RCC should be included in the differential diagnosis of fat-containing liver masses as observed on chemical shift MRI.

Fat detection in gallbladder carcinoma with extensive xanthogranulomatous change demonstrated by chemical shift MR imaging

We present a case of gallbladder carcinoma, in which fat was detected on dual-echo chemical shift magnetic resonance imaging (MRI). Histologic analysis showed poorly differentiated adenocarcinoma associated with massive xanthogranulomatous change. Sudan IV staining successfully confirmed the presence of fat within the interstitial histiocytes. Although rare, gallbladder carcinoma with xanthogranulomatous change should be included in the differential diagnosis of fatty tumor involving the region of the liver as observed on chemical shift MRI.