Peritumoral Injection Research Articles

Abstract 5571: Immune-checkpoint inhibition via enzyme-mediated degradation of kynurenine

Abstract Tryptophan oxidation and the ensuing production of Kynurenine (Kyn) and downstream products have been established to play an important role in immunosuppression within the tumor microenvironment (TME). The rate limiting step in Tryptophan oxidation is catalyzed by the IFN-γ inducible IDO-1 enzyme which is upregulated in numerous cancers and also, in some instances via the ectopic expression of TDO, which is normally expressed primarily in the liver. Currently, IDO-1 small molecule inhibitors in combination with checkpoint inhibitor antibodies are being evaluated in >12 clinical trials. However, whether the immune-suppressive effects of Tryptophan catabolism results from its depletion in the TME, or from the accumulation of Kynurenine, is not known. To distinguish between the effects of Trp depletion and Kyn accumulation in the TME we used an engineered Kynureninase (KYNase) enzyme that selectively degrades Kyn into immunologically inert and non-toxic metabolites. Peritumoral injection of PEGylated KYNase completely depletes serum and tumor Kyn levels for up to 72 hrs, while leaving Trp concentrations in both compartments unaffected. In the IDO-1 expressing CT26 colon carcinoma model KYNase treatment as monotherapy resulted in 16% complete and durable responses, accompanied by long-term immunity to tumor re-challenge. KYNase had no effect on tumor growth in IDO-/- mice, nor in RAG-/- or in CD8+ T cell depleted mice. Analysis of the TME demonstrated KYNase treatment resulted in increased accumulation of CD8+ cells, with a greater proportion expressing Granzyme B, undergoing proliferation and permeating the tumor interior. This effect was specific to the TME, as no detectable changes to the immune compartment occurred in other organs examined, nor overt signs of autoimmunity and toxicity. The increase in CD8+ cells was consistent with in vitro data showing that elevated concentration of Kyn directly induces apoptosis of activated CD8+ T cells partially through IL-2 suppression. No changes to the Treg percentages and phenotypes in the TME were observed, indicating that the Treg compartment is not impacted by treatment with KYNase. Cytokine analysis of tumor digests revealed increased IL-2 concentrations, as well as IFNγ and IL-9, in tumors after KYNase treatment. Furthermore, ex vivo stimulation of TIL after KYNase treatment demonstrated that the increase in cytokines in the TME is not solely due to an increase in TIL, but also an increased effector cytokine capacity on a per cell basis. Administration of KYNase together with either αCTLA4 or αPD1 synergistically elicited complete and durable regression of multiple established tumor models. In summary, our data support the hypothesis that Kyn accumulation in the TME rather than Trp depletion is the dominant IDO-mediated immune suppressive mechanism, and that enzyme-mediated Kyn depletion is a promising cancer immunotherapeutic approach. Citation Format: Todd A. Triplett, Kendra Triplett, Everett Stone, Michelle Zhang, Mark Manfredi, Candice Lamb, Yuri Tanno, Lauren Ehrlich, George Georgiou. Immune-checkpoint inhibition via enzyme-mediated degradation of kynurenine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5571. doi:10.1158/1538-7445.AM2017-5571

Factors and conditions affecting the antitumor effect of magnetite nanoparticles in the experiments in vivo.

e14051 Background: Independent antitumor effects of magnetite nanoparticles (NPs) in animals, up to complete regression of large tumors, have been demonstrated. Factors and conditions that contribute to the appearance and enhancement of such effects are an important issue. Our purpose was to study the dependence of antitumor effects of magnetite NPs on characteristics of animals, ways of preparation and injection of NPs and weak magnetic fields (WMF). Methods: The experiment included 380 white outbred rats with transplantable sarcoma 45 (S45), Pliss lymphosarcoma (PL) and Heren carcinoma (HC) and 230 С57Black/6 mice with B16 melanoma. The animals received 6-8 1.25-35.4 mg/kg peritumoral or intraperitoneal injections of a water-based magnetite NP ferrofluid (FF) diluted with saline solution. WMF parameters were: 0.03-9 Hz frequency, 0.7-3.2 mT induction, exposure on the head. Dynamics of tumor sizes, histological changes and FF characteristics after the dilution with saline (X-ray absorption spectroscopy analysis) were evaluated. Results: An effective single dose in S45 female rats with peritumoral injections was higher than in males (35.4 and 17.7 mg/kg, respectively). Female rats with HC were sensitive to small NP doses (1.25 mg/kg) in intraperitoneal (but not peritumoral) injections (regression in > 30%). Peritumoral injections of small NP doses were most effective in PL males, while a number of experiments did not show benefits of small NP doses for mice. NP solution storage led to its lower effect due to the oxidation of Fe +2 to Fe +3, and even FF dilution ex tempora decreased the effect as SS pH changed to 7.4. WMF was able to enhance the effect of NPs by up to 1.5 times but not in intraperitoneal injections. Conclusions: Antitumoral effects of NPs depended on species of animals and their gender, tumor types, doses and methods of NP injections, storage time of diluted FF prior to its injection, saline pH, and WMF. WMF effects were different depending on NP injection methods.

Systemic effects of cAMP in chemotherapy for Heren’s carcinoma.

e14052 Background: Along with tumor itself, mechanisms of regulation of homeostasis are the target for tumor progression inhibition. The brain, various organs and tumor have different resources of energetic and metabolic substrates. Involvement of cyclic adenosine monophosphate (cAMP) into intimate mechanisms of proliferation, hormonal and energetic homeostasis indicates the possibility to use this factor in chemotherapy of tumors to improve the resistance of the organism. The purpose of the study was to analyze levels of endogenous cAMP in tumor and in organs as a criterium of systemic body response to chemotherapy with cAMP application. Methods: The study included 56 male Wistar rats with Heren’s carcinoma receiving peritumoral injections of cyclophosphan (CP) 50 mcg/kg (Baxter Oncology GmbH, Germany) alone and in combination with cAMP (Sigma-Aldrich, USA), P.O. at a concentration of 0.01%. cAMP levels in homogenates of organs and tumors were measured by immunoradiometric assay (Immunotech, Czech Republic) using Arian radiometer (Vitaco, Russia). Data were processed using Statistica 6. Results: cAMP levels in growing tumors in rats without treatment (the control) were maximal (7.03±1.5 nmol/L). CP injections alone during inhibition of carcinoma growth allowed the reduction of tumor cAMP level by 3.3 times. Combination of CP and cAMP resulted in tumor regression, and endogenous cAMP levels in tumor decreased by 10 times compared with the control. Similar dynamics of cAMP reductions was noted in the adrenal glands. The lungs, thymus, lymph nodes and especially the testes and the brain, on the contrary, showed accumulation of cAMP to the normal levels and higher. Conclusions: The range of cAMP levels in organs and tumors of rats receiving combination of CP and cAMP demonstrated the development of adaptive and regenerative processes in organs responsible for the neuroendocrine regulation, suppression of stimulation of stress-realizing systems and metabolic support of the processes of increasing non-specific antitumor resistance along with inhibited proliferative activity of tumors.

Antitumor Activity of a Mesenchymal Stem Cell Line Stably Secreting a Tumor-Targeted TNF-Related Apoptosis-Inducing Ligand Fusion Protein.

Mesenchymal stem cells (MSCs) are currently exploited as gene delivery systems for transient in situ expression of cancer therapeutics. As an alternative to the prevailing viral expression, we here describe a murine MSC line stably expressing a therapeutic protein for up to 42 passages, yet fully maintaining MSC features. Because of superior antitumoral activity of hexavalent TNF-related apoptosis-inducing ligand (TRAIL) formats and the advantage of a tumor-targeted action, we choose expression of a dimeric EGFR-specific diabody single-chain TRAIL (Db-scTRAIL) as a model. The bioactivity of Db-scTRAIL produced from an isolated clone (MSC.TRAIL) was revealed from cell death induction in Colo205 cells treated with either culture supernatants from or cocultured with MSC.TRAIL. In vivo, therapeutic activity of MSC.TRAIL was shown upon peritumoral injection in a Colo205 xenograft tumor model. Best antitumor activity in vitro and in vivo was observed upon combined treatment of MSC.TRAIL with bortezomib. Importantly, in vivo combination treatment did not cause apparent hepatotoxicity, weight loss, or behavioral changes. The development of well characterized stocks of stable drug-producing human MSC lines has the potential to establish standardized protocols of cell-based therapy broadly applicable in cancer treatment.

Laparoscopic subperitoneal injection of chemo-loaded particles lowers tumor growth on a rabbit model of peritoneal carcinomatosis.

The purpose of our study was to assess the effect of controlled-release chemotherapy on the growth and viability of peritoneal carcinomatosis treated by subperitoneal injection in a rabbit VX2 model. A model of peritoneal carcinomatosis was created by laparoscopic injection of VX2 tumor in the left and right broad ligaments of 12 White New Zealand rabbits. At day 12, each tumor was randomly treated with a peritumoral injection of 0.5 mL microspheres loaded with doxorubicin (DEM-DOX) or unloaded (DEM-BLAND). Seven days after treatment, tumor volume, tumor viability in histology, local tumor necrosis in contact with DEM, and doxorubicin concentration profile around the drug eluting microspheres (DEM) were measured. Tumor volume was significantly lower in the DEM-DOX group (3.6 ± 3.2 cm3) compared with the DEM-BLAND group (8.9 ± 5.4 cm3) (p = 0.0425). The percentage of viable tumor tissue was significantly lower in the DEM-DOX group (38% ± 17%) compared with the DEM-BLAND group (56% ± 20%) (p = 0.0202). Tissue necrosis was observed around all DEM-DOX up to a distance of 1.094 ± 0.852 mm and never observed around DEM-BLAND. Drug concentration was above the therapeutic level of 1.0 µM up to a distance of 1.4 mm from the DEM to the tumor. Laparoscopic subperitoneal injection of chemo-loaded particles is feasible and lowers tumor growth and viability in a rabbit model of peritoneal carcinomatosis after 1 week.

Noninvasive delivery of oligonucleotide by penetratin-modified polyplexes to inhibit protein expression of intraocular tumor

Our present study aimed to develop an antisense oligonucleotide (ASO) delivery system to achieve gene silencing in intraocular tumor via topical instillation. ASO specific for luciferase was chosen as model drug, polyamidoamine (PG5) was employed to condense ASO, and penetratin (Pene) was used to enhance cellular uptake. Nanoscale PG5/ASO/Pene polyplex was stabilized via noncovalent bonding. In vitro evaluations indicated that PG5/ASO/Pene exhibited improved cell-penetrating and gene silencing ability compared with naked ASO and PG5/ASO. Subcutaneous and orthotopic tumor models expressing luciferase were established in nude mice. After treated by PG5/ASO/Pene, immunohistochemical results of subcutaneous tumors showed significant inhibition of luciferase expression via peritumoral injection, and bioluminescence from orthotopic tumor was obviously weakened via topical instillation. To date, few works were successful in noninvasive treatment of intraocular diseases using antisense strategy, this penetratin-modified polyplex could be a promising vector to inhibit protein expression by effectively delivering ASOs into the eye.

Interleukin-15 and cisplatin co-encapsulated thermosensitive polypeptide hydrogels for combined immuno-chemotherapy

In situ-forming thermosensitive hydrogels based on poly(ethylene glycol)-poly(γ-ethyl-l-glutamate) diblock copolymers (mPEG-b-PELG) were prepared for the co-delivery of interleukin-15 (IL-15) and cisplatin (CDDP). The polypeptide-based hydrogels as local drug delivery carriers could reduce the systemic toxicity, degrade thoroughly within 3weeks after subcutaneous injection into rats and display an acceptable biocompatibility. When incubated with mouse melanoma B16 cells, only the CDDP-treated groups had significant effects on the S phase cell-cycle arrest in melanoma cells. After a single peritumoral injection of the hydrogel containing IL-15/CDDP in C57BL/6 mice inoculated with B16F0-RFP melanoma cells, the dual drug-loaded hydrogels displayed synergistic anticancer efficacy, which was resulted from a combination of CDDP-mediated S arrest and IL-15/CDDP-induced recovery of CD8+ T cell and NK cell populations to reduce immunosuppression and enhance antitumor immunity. Hence, the as-prepared thermosensitive polypeptide hydrogels for localized and sustained co-delivery of IL-15 and CDDP may have potential for efficient treatment of melanoma.

MP18-10 COMPARISON OF PLANAR SCINTIGRAPHY AND SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY /COMPUTED TOMOGRAPHY (SPECT/CT) IN PREOPERATIVE IMAGING OF SENTINEL LYMPH NODES IN PENILE CANCER PATIENTS

You have accessJournal of UrologyImaging/Radiology: Uroradiology III1 Apr 2017MP18-10 COMPARISON OF PLANAR SCINTIGRAPHY AND SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY /COMPUTED TOMOGRAPHY (SPECT/CT) IN PREOPERATIVE IMAGING OF SENTINEL LYMPH NODES IN PENILE CANCER PATIENTS Carsten Maik Naumann, Moritz Franz Hamann, Christian Colberg, Klaus-Peter Jünemann, Daniar Osmonov, and Ulf Lützen Carsten Maik NaumannCarsten Maik Naumann More articles by this author , Moritz Franz HamannMoritz Franz Hamann More articles by this author , Christian ColbergChristian Colberg More articles by this author , Klaus-Peter JünemannKlaus-Peter Jünemann More articles by this author , Daniar OsmonovDaniar Osmonov More articles by this author , and Ulf LützenUlf Lützen More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.620AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The aim of this study was to evaluate the diagnostic value of SPECT/CT and planar lymphoscintigraphy in preoperative imaging of sentinel lymph nodes in penile cancer patients with non-palpable inguinal lymph nodes. METHODS Radio-labelling of sentinel nodes was performed by intradermal and peritumoral injection of 150MBq Tc-99 m-labelled nanocolloids according to the two day protocol. Image acquisition of planar scintigraphies was carried out by a twin head gamma camera (Siemens, ECAM and Symbia S) and indirect body contouring. Additionally, we subsequently performed SPECT/CT of the abdomen und inguinal regions using a twin-head hybrid camera system (Siemens Symbia T and Symbia Intevo). Imaging data of both modalities were prospectively evaluated by two experienced physicians in consensus reading in 52 groins of 26 patients with this tumor entity. RESULTS A total of 71 SLNs in 37 groins were identified by planar scintigraphy. Non-visualization was observed in 15 (28.8%) inguinal basins using planar scans. 82 SLNs in 42 groins were detected by SPECT/CT (non-visualization in 10 (19.2%) groins). SPECT/CT revealed 8 inguinal hotspots as shown by planar imaging in 7 groins as false positive. 19 inguinal SLNs in 16 groins were missed on planar imaging and could be detected by SPECT/CT only. In contrast to 2D planar scintigraphy, SPECT/CT allowed to determine the precise anatomical localization of the SLNs in all 42 groins. CONCLUSIONS SPECT/CT is capable of detecting SLNs missed by planar imaging, it reduces the number of false positive findings and shows the morphological location of SLNs more accurately. If available, SPECT/CT should be used for preoperative SLN imaging in penile cancer patients with non-palpable inguinal lymph node status. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e223-e224 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Carsten Maik Naumann More articles by this author Moritz Franz Hamann More articles by this author Christian Colberg More articles by this author Klaus-Peter Jünemann More articles by this author Daniar Osmonov More articles by this author Ulf Lützen More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Sentinel Node Mapping Using a Fluorescent Dye and Visible Light During Laparoscopic Gastrectomy for Early Gastric Cancer: Result of a Prospective Study From a Single Institute.

The aim of this study was to investigate the feasibility of sentinel node mapping using a fluorescent dye and visible light in patients with gastric cancer. Recently, fluorescent imaging technology offers improved visibility with the possibility of better sensitivity or accuracy in sentinel node mapping. Twenty patients with early gastric cancer, for whom laparoscopic distal gastrectomy with standard lymphadenectomy had been planned, were enrolled in this study. Before lymphadenectomy, the patients received a gastrofiberoscopic peritumoral injection of fluorescein solution. The sentinel basin was investigated via laparoscopic fluorescent imaging under blue light (wavelength of 440-490 nm) emitted from an LED curing light. The detection rate and lymph node status were analyzed in the enrolled patients. In addition, short-term clinical outcomes were also investigated. No hypersensitivity to the dye was identified in any enrolled patients. Sentinel nodes were detected in 19 of 20 enrolled patients (95.0%), and metastatic lymph nodes were found in 2 patients. The latter lymph nodes belonged to the sentinel basin of each patient. Meanwhile, 1 patient (5.0%) experienced a postoperative complication that was unrelated to sentinel node mapping. No mortality was recorded among enrolled cases. Sentinel node mapping with visible light fluorescence was a feasible method for visualizing sentinel nodes in patients with early gastric cancer. In addition, this method is advantageous in terms of visualizing the concrete relationship between the sentinel nodes and surrounding structures.

Copper sulfide nanoparticle-based localized drug delivery system as an effective cancer synergistic treatment and theranostic platform

In recent years, localized cancer treatment using different biomaterials has attracted increasing attention for effective inhibition of tumor growth. However, it is still challenging for this kind of system to achieve a high drug loading, overcome biological barriers from the site of injection to the site of action, and combine synergetic therapy with diagnosis without adversely affecting the formation process. This study provides a localized diffusion molecular retention (DMR) tumor targeting drug delivery system based on hollow mesoporous copper sulfide nanoparticles (HMCuS NPs) entrapment of anticancer drug for the first time, which can achieve high drug loading, improve local drug accumulation and retention, accomplish synergistic combination of chemo-phototherapy, and finally enhance antitumor effect. In addition, HMCuS NPs also possesses the property suitable for photoacoustic imaging, which could offer us a theranostic platform.

Gambogic acid-loaded PEG–PCL nanoparticles act as an effective antitumor agent against gastric cancer

Poor water solubility and side effects hampered the clinical application of gambogic acid (GA) in cancer therapy. Accordingly, GA-loaded polyethylene glycol-poly(ɛ-caprolactone) (PEG–PCL) nanoparticles (GA-NPs) were developed and administered peritumorally to evaluate their antitumor activity. The particle size, polydispersity index, encapsulation efficiency and loading capacity of GA-NPs were 143.78 ± 0.054 nm, 0.179 ± 0.004, 81.3 ± 2.5% and 14.8 ± 0.6%, respectively. In addition, GA-NPs showed excellent stability, good biocompatibility and sustained release profile. Endocytosis studies in vitro demonstrated that the GA-NPs were effectively taken up by tumor cells in a time-dependent manner. In vivo real-time imaging showed that the nanoparticles effectively accumulated within the tumor tissue after peritumoral administration. The cytotoxicity study revealed that the GA-NPs effectively inhibited the proliferation of gastric cancer cells. In vivo antitumor therapy with peritumoral injection of GA-NPs exhibited superior antitumor activity compared with free GA. Moreover, no toxicity was detected in any treatment group. Histological studies confirmed a lower cell density and a higher number of apoptotic cells in the GA-NPs group compared with the free GA group. Furthermore, the expression level of the cysteine proteases 3 precursor (pro-caspase3), a crucial component of cellular apoptotic pathways, was efficiently reduced in mice treated with GA-NPs. In conclusion, the GA-NPs system provided an efficient drug delivery platform for chemotherapy.

Contrast-enhanced ultrasound mapping of sentinel lymph nodes in oral tongue cancer-a pilot study.

To assess the usefulness of contrast-enhanced ultrasound (CEUS) with peritumoral injection of microbubble contrast agent for detecting the sentinel lymph nodes for oral tongue carcinoma. The study was carried out on 12 patients with T1-2cN0 oral tongue cancer. A radical resection of the primary disease was planned; a modified radical supraomohyoid neck dissection was reserved for patients with larger lesions (T2, n = 8). The treatment plan and execution were not influenced by sentinel node mapping outcome. The Sonovue™ contrast agent (Bracco Imaging, Milan, Italy) was utilized. After detection, the position and radiologic features of the sentinel nodes were recorded. The identification rate of the sentinel nodes was 91.7%; one patient failed to demonstrate any enhanced areas. A total of 15 sentinel nodes were found in the rest of the 11 cases, with a mean of 1.4 nodes for each patient. The sentinel nodes were localized in: Level IA-1 (6.7%) node; Level IB-11 (73.3%) nodes; Level IIA-3 (20.0%) nodes. No contrast-related adverse effects were observed. For oral tongue tumours, CEUS is a feasible and potentially widely available approach of sentinel node mapping. Further clinical research is required to establish the position of CEUS detection of the sentinel nodes in oral cavity cancers.

INDIRECT COMPUTED TOMOGRAPHIC LYMPHOGRAPHY FOR ILIOSACRAL LYMPHATIC MAPPING IN A COHORT OF DOGS WITH ANAL SAC GLAND ADENOCARCINOMA: TECHNIQUE DESCRIPTION.

Sentinel lymph node mapping can help to direct surgical oncologic staging and metastatic disease detection in patients with complex lymphatic pathways. We hypothesized that indirect computed tomographic lymphography (ICTL) with a water-soluble iodinated contrast agent would successfully map lymphatic pathways of the iliosacral lymphatic center in dogs with anal sac gland carcinoma, providing a potential preoperative method for iliosacral sentinel lymph node identification in dogs. Thirteen adult dogs diagnosed with anal sac gland carcinoma were enrolled in this prospective, pilot study, and ICTL was performed via peritumoral contrast injection with serial caudal abdominal computed tomography scans for iliosacral sentinel lymph node identification. Technical and descriptive details for ICTL were recorded, including patient positioning, total contrast injection volume, timing of contrast visualization, and sentinel lymph nodes and lymphatic pathways identified. Indirect CT lymphography identified lymphatic pathways and sentinel lymph nodes in 12/13 cases (92%). Identified sentinel lymph nodes were ipsilateral to the anal sac gland carcinoma in 8/12 and contralateral to the anal sac gland carcinoma in 4/12 cases. Sacral, internal iliac, and medial iliac lymph nodes were identified as sentinel lymph nodes, and patterns were widely variable. Patient positioning and timing of imaging may impact successful sentinel lymph node identification. Positioning in supported sternal recumbency is recommended. Results indicate that ICTL may be a feasible technique for sentinel lymph node identification in dogs with anal sac gland carcinoma and offer preliminary data to drive further investigation of iliosacral lymphatic metastatic patterns using ICTL and sentinel lymph node biopsy.

Combination of TLR9 agonist lefitolimod/MGN1703 with checkpoint inhibitors for cancer immunotherapy.

634 Background: TLR9 agonists are potent activators of the immune system via induction of cellular and humoral responses. Preclinical and ongoing clinical studies support the use of TLR9 agonists for immunotherapeutic approaches. Lefitolimod/MGN1703 is a covalently-closed dumbbell-like immune surveillance reactivator (ISR) with a broad immunomodulatory potential. After promising data from a phase II trial (IMPACT) as maintenance therapy after first-line induction chemotherapy in patients with metastatic colorectal cancer lefitolimod is recently evaluated in a phase III trial in mCRC patients (IMPALA). Methods: It was previously shown that lefitolimod can reduce tumor growth in several murine tumor models. Since the mode-of-action of lefitolimod starts upstream of the initiation points of checkpoint inhibitors aCTLA-4 or aPD-1/aPD-L1 a combinatory approach may result in an enhanced anti-tumor effect. Therefore, we employed two syngeneic murine tumor models: One with s.c. inoculation of CT26 cells and another with s.c. A20 cell challenge. Multiple doses of lefitolimod were injected s.c. or i.tu. Results: In the colon carcinoma CT26 model i.p. injection of aPD-L1 had no effect on the tumor growth, whereas peritumoral injection of lefitolimod led to a slowed tumor growth. The tumor growth was further inhibited by the combination (tumor growth inhibition, TGI - aPD-L1: no, lefitolimod: 28%, combination: 48%) resulting in prolonged survival of the mice. This combinatory effect was even more pronounced in the lymphoma A20 model: Injections of anti-PD-1 (i.p.) or lefitolimod (i.tu.) alone had a moderate anti-tumor effect which was vastly increased by the combination (TGI - aPD-1: 46%, lefitolimod: 50%, combination: 99%). Conclusions: In conclusion, we showed that lefitolimod, a member of dSLIM family of TLR9 agonists and an ISR, can enhance the limited anti-tumor effects of checkpoint inhibitors in pilot studies in murine colon carcinoma and lymphoma tumor models in vivo. These data show the promising potential for the combination with checkpoint inhibitors. In fact, a clinical trial in cooperation with MD Anderson evaluating the benefit of lefitolimod in combination with ipilimumab is currently ongoing.

Dynamic sentinel node biopsy for penile cancer: an initial experience in an Irish Hospital.

The presence of nodal metastases is the single most important prognostic factor in penile cancer. However, reliable assessment of nodal status in clinically node-negative (cN0) patients poses a challenge. Approximately 20% of these patients harbour occult nodal metastases. Currently available non-invasive radiological investigations are unreliable in excluding micrometastatic disease. Dynamic sentinel node biopsy (DSNB) is a minimally invasive procedure for assessing lymph node involvement. We report our initial experience with DSNB in assessing the status of regional lymph nodes in cN0 penile cancer patients. DSNB was performed in penile cancer patients with at least one cN0 groin. All patients undergoing DSNB at our institution were included. Lymphoscintigraphic images were obtained from all patients, after intradermal, peritumoral injection of a Technetium-99m nanocolloid. The sentinel nodes were defined as the nodes identified on lymphoscintigraphy, which were also radioactive intraoperatively using a gamma probe. In total, 18 groins from 11 patients underwent DSNB. Of these, 11 patients underwent bilateral DSNB and 4 had unilateral DSNB. The mean (range) age of patients at the time of presentation of their primary tumour was 63 (39-78) years. A mean of 1.2 nodes per groin was retrieved. One lymph node was positive in one patient, who subsequently underwent a bilateral inguinal lymph node dissection. Overall, the median (range) follow-up was 12.8 (2.7-31.3) months with no local or regional recurrences. Further cases and longer follow-up will define the accuracy of this technique in the Irish population.

Radiotherapy and MVA-MUC1-IL-2 vaccine act synergistically for inducing specific immunity to MUC-1 tumor antigen

BackgroundWe previously demonstrated that tumor irradiation potentiates cancer vaccines using genetic modification of tumor cells in murine tumor models. To investigate whether tumor irradiation augments the immune response to MUC1 tumor antigen, we have tested the efficacy of tumor irradiation combined with an MVA-MUC1-IL2 cancer vaccine (Transgene TG4010) for murine renal adenocarcinoma (Renca) cells transfected with MUC1.MethodsEstablished subcutaneous Renca-MUC1 tumors were treated with 8 Gy radiation on day 11 and peritumoral injections of MVA-MUC1-IL2 vector on day 12 and 17, or using a reverse sequence of vaccine followed by radiation. Growth delays were monitored by tumor measurements and histological responses were evaluated by immunohistochemistry. Specific immunity was assessed by challenge with Renca-MUC1 cells. Generation of tumor-specific T cells was detected by IFN-γ production from splenocytes stimulated in vitro with tumor lysates using ELISPOT assays.ResultsTumor growth delays observed by tumor irradiation combined with MVA-MUC1-IL-2 vaccine were significantly more prolonged than those observed by vaccine, radiation, or radiation with MVA empty vector. The sequence of cancer vaccine followed by radiation two days later resulted in 55–58% complete responders and 60% mouse long-term survival. This sequence was more effective than that of radiation followed by vaccine leading to 24–30% complete responders and 30% mouse survival. Responding mice were immune to challenge with Renca-MUC1 cells, indicating the induction of specific tumor immunity. Histology studies of regressing tumors at 1 week after therapy, revealed extensive tumor destruction and a heavy infiltration of CD45+ leukocytes including F4/80+ macrophages, CD8+ cytotoxic T cells and CD4+ helper T cells. The generation of tumor-specific T cells by combined therapy was confirmed by IFN-γ secretion in tumor-stimulated splenocytes. An abscopal effect was measured by rejection of an untreated tumor on the contralateral flank to the tumor treated with radiation and vaccine.ConclusionsThese findings suggest that cancer vaccine given prior to local tumor irradiation augments an immune response targeted at tumor antigens that results in specific anti-tumor immunity. These findings support further exploration of the combination of radiotherapy with cancer vaccines for the treatment of cancer.

Periareolar or Peritumoral Injection of Isosulfan Blue and the Effect on the Number of Sentinel Lymph Nodes Examined

The conduct of sentinel node biopsy (SLNBx) for breast cancer (BC) has evolved substantially since its original description. No national standards for the performance of SLNBx exist, therefore, we sought to determine the effect of isosulfan blue (ISB) injection technique on nodal harvesting and staging accuracy during SLNBx. Our main outcome measures included the number of SLNs examined and the number of positive axillae in patients undergoing SLNBx after injection of filtered sulfur colloid intradermally and either small volume ISB injected in the periareolar dermis (PA,∼0.75 cc) or large volume peritumoral (PT, 5 cc). Between January 1, 2009, and September 30, 2013, 1357 patients at an academic/community practice setting underwent SLNBx of which 966 (71.2%) were node negative. These patients ranged in age from 27 to 97 years (mean 60.1 years). The majority of patients (76%) underwent PT injection of ISB. There was no significant difference in the mean age of these two groups (61.2 PT vs 59.7 PA years). All were female. The majority of patients (72.7%) had T1 primaries. Nearly 73 per cent of patients were Luminal A/B, 10.8 per cent HER, and 16.4 per cent were triple negative. There was no significant difference in the distribution of T stage (P = 0.56) or breast cancer subtypes between the techniques (P = 0.59). The mean number of nodes examined was 3.1 (range, 1-18). PT patients had a mean of 3.5 (range, 1-18) nodes, whereas PA patients had a mean of 2.4 nodes (range, 1-10) (P < 0.001). The technical aspects of injecting ISB affect the number of nodes harvested during SLNBx but not staging accuracy.

Feasibility of sentinel lymph node dissection using Tc-99m phytate in papillary thyroid carcinoma

PurposeVarious methods of sentinel lymph node (SLN) biopsy in thyroid cancer have been introduced. Tc-99m phytate as a radiotracer has been successfully utilized for SLN biopsy in breast, cervix, and endometrial cancer. We assessed the feasibility of SLN dissection using Tc-99m phytate in papillary thyroid carcinoma (PTC).MethodsSeventeen patients with PTC were prospectively enrolled. Ultrasound-guided peritumoral injection of 55.5 MBq Tc-99m phytate in 0.25-mL normal saline was performed. Preoperative single-photon emission-computed tomography (SPECT) and intraoperative gamma-probe were used for SLN detection during operation.ResultsIdentification rate of SLNs was 70.6% (12 of 17) with SPECT, and 88.2% (15 of 17) with gamma-probe. Combined SPECT and gamma-probe had identification rates of 88.2% (15 of 17). Identification rates of SLNs in central LN compartments were 82.4% (14 of 17) and 41.2% (7 of 17) in lateral LN compartments. Overall sensitivity, specificity, positive predictive value, and negative predictive value of the results of SLN biopsy were 91.6%, 100%, 88.4%, and 100%, respectively. Eight patients (47.1%) had metastasis in SLNs; all patients had SLN metastasis in the central compartment and 2 patients had SLN metastasis in both the central and lateral compartments.ConclusionCombined SPECT and gamma-probe could detect SLNs with an 88.2% identification rate in PTC. SLN biopsy using Tc-99m phytate is technically feasible. Further investigation is warranted for clinical application of Tc-99m phytate in PTC.

Recombinant Parvoviruses Armed to Deliver CXCL4L1 and CXCL10 Are Impaired in Their Antiangiogenic and Antitumoral Effects in a Kaposi Sarcoma Tumor Model Due To the Chemokines' Interference with the Virus Cycle.

Application of oncolytic viruses is a valuable option to broaden the armament of anticancer therapies, as these combine specific cytotoxic effects and immune-stimulating properties. The self-replicating H-1 parvovirus (H-1PV) is a prototypical oncolytic virus that, besides targeting tumor cells, also infects endothelial cells, thus combining oncolytic and angiostatic traits. To increase its therapeutic value, H-1PV can be armed with cytokines or chemokines to enhance the immunological response. Some chemokines-more specifically, the CXCR3 ligands CXCL4L1 and CXCL10-combine immune-stimulating properties with angiostatic activity. This study explores the therapeutic value of recombinant parvoviruses carrying CXCL4L1 or CXCL10 transgenes (Chi-H1/CXCL4L1 or Chi-H1/CXCL10, respectively) to inhibit the growth of the human Kaposi sarcoma cell line KS-IMM. KS-IMM cells infected by Chi-H1/CXCL4L1 or Chi-H1/CXCL10 released the corresponding chemokine and showed reduced migratory capacity. Therefore, the antitumoral capacity of Chi-H1/CXCL4L1 or Chi-H1/CXCL10 was tested in mice. Either in vitro infected KS-IMM cells were injected or subcutaneously growing KS-IMM xenografts were treated by peritumoral injections of the different viruses. Surprisingly, the transgenes did not increase the antitumoral effect of natural H-1PV. Further experiments indicated that CXCL4L1 and CXCL10 interfered with the expression of the viral NS1 protein in KS-IMM cells. These results indicate that the outcome of parvovirus-based delivery of CXCR3 ligands might be tumor cell type dependent, and hence its application must be considered carefully.

Comparison of (99)Tcm -rituximab planar and SPECT / CT lymphoscintigraphy for sentinel lymph nodes of breast cancer

Objective To investigate the advantages of SPECT/CT in preoperative SLN localization of primary breast cancer by comparing with planar lymphoscintigraphy in the same patient. Methods From May 2015 to December 2015, 104 female patients (age range: 33-82 years, average age(59.71±12.33)years) with stageⅠ-Ⅱbreast cancer had preoperative peritumoral injection of 18.5 MBq (0.5 ml) of 99Tcm-rituximab under the guidance of ultrasound. Planar and SPECT/CT lymphoscintigraphy were acquired at 2-4 h post injection since SLN detection was difficult on skin of axilla by a handheld portable detector at 2 h after injection. Axillary SLNs were detected by a handheld portable detector and examined pathologically with both HE and immunohistochemical staining. χ2 test and paired t test were used for data analysis. Results The success rate of planar imaging and SPECT/CT was 88.46%(92/104) and 98.08%(102/104), respectively, with statistically significant difference (χ2=7.658, P<0.05). Negative imaging was more common in older patients, or those with history of neoadjuvant chemotherapy or metastatic SLNs. The numbers of SLNs detected by the 2 imaging methods were 122 vs 166 or (1.17±0.73)/patient vs (1.60±0.95)/patient (t=2.533, P<0.01). SLNs were found in axilla, internal mammary and interpectoral stations. The patients received an additional (3.41±0.59) mSv effective dose in SPECT/CT compared with planar imaging. A total of 174 axillary fossa and/or interpectoral SLNs were harvested by a handheld portable gamma detector in 84 cases, and 46 SLNs in 17 patients were pathologically confirmed as metastasis. Conclusion SPECT/CT could detect more SLNs and is more accurate than planar lymphoscintigraphy, suggesting that it is useful in SLN biopsy of breast cancer. Key words: Breast neoplasms; Sentinel lymph node biopsy; Tomography, emission-computed, single-photon; Tomography, X-ray computed; Antibodies, monoclonal