Noriaki Kameyama

Photodynamic Therapy Using an Anti-EGF Receptor Antibody Complexed with Verteporfin Nanoparticles: A Proof of Concept Study

Photodynamic therapy (PDT) is a noninvasive optical treatment method in which the topical or systemic delivery of photosensitizing drugs is followed by irradiation with broadband red light. Coupling photosensitizers with a specific antibody may allow this approach to target specific cancers. This study determines the antitumor efficacy of coupling verteporfin (Visudyne(®)), a hydrophobic polyporphryin oligomer, with an antiepidermal growth factor receptor (anti-EGFR) antibody. Poly[2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate-co-p-nitrophenylcarbonyloxyethyl methacrylate] (PMBN) was conjugated with an anti-EGFR antibody and mixed with verteporfin (verteporfin-PMBN-antibody complex). Tumor-bearing mice were intravenously injected with the verteporfin-PMBN-antibody complex or verteporfin plus PMBN without the antibody. Irradiation was conducted at 640 nm with a dose of 75 J/cm(2). The fluorescence intensity in A431 cells in vitro was threefold higher after exposure to verteporfin-PMBN-antibody complex than after exposure to verteporfin-PMBN. In A431 tumor-bearing mice, the intratumor concentration of verteporfin was 9.4 times higher than that of the skin, following administration of the verteporfin-PMBN-antibody complex. Tumor size significantly decreased within 8 days in mice treated with verteporfin-PMBN-antibody complex compared with those treated with verteporfin-PMBN. PDT using a PMBN-verteporfin-antibody complex offers a promising anticancer therapy.

Immunosuppressive and Anticancer Effect of a Mammalian Ribonuclease that Targets High-affinity Interleukin-2-receptors

OBJECTIVE To target high-affinity interleukin (IL)-2 receptors involved in lymphocyte proliferation processes such as allograft rejection, autoimmune disorders, and certain haematological malignancies, using a minimally immunogenic mammalian-derived enzyme, bovine RNaseA, which becomes cytotoxic on entering cytoplasm. DESIGN Laboratory study. SETTING Teaching hospital, Japan. MATERIAL Human lymphocytes isolated from healthy histoincompatible donors in mixed lymphocyte cultures or stimulated with phytohemagglutinin (PHA) to promote IL-2Ralpha expression. MJ, an HTLV-1-infected malignant T-cell line that overexpresses IL-2Ralpha, and the IL-2Ralpha-negative cell lines MOLT-4F and MT-1, were used as controls. INTERVENTIONS Bovine RNaseA was chemically conjugated to 7G7B6, a monoclonal antibody to the alpha-chain of human IL-2 receptors, and several concentrations of the conjugates were added to the lymphocyte cultures. MAIN OUTCOME MEASURES Inhibition of cell proliferation as a percentage of 3H-thymidine incorporation in 24 hours. RESULTS 7G7B6-RNaseA dose-dependently inhibited cell proliferation in PHA-stimulated human lymphocytes at a 50% inhibitory concentration (IC50) of 2 x 10(-7) M. whereas RNase alone and RNase plus antibody had no inhibitory effect. 7G7B6-RNaseA also dose-dependently inhibited the human mixed lymphocyte reaction at an IC50 of 2 x 10(-6) M, whereas RNase alone did not. The conjugate also inhibited cell proliferation in MJ cells, a cell line that is infected with HTLV-I and overexpresses the high-affinity IL-2 receptor, at an IC50 of 5 x 10(-7) M. However the conjugate had no inhibitory effect on the IL-2 receptor non-expressing human T-cell lymphoblastic leukaemia cell lines MOLT-4F or MT-1. CONCLUSION 7G7B6-RNaseA can inhibit cell proliferation in antigen- or mitogen-stimulated lymphocytes that overexpress high-affinity IL-2 receptors, and it may be safer than conventional chemotherapy or immunotoxins in the treatment of transplant rejection, certain lymphocytic malignancies, and other IL-2R-associated diseases, because it contains a mammalian cytotoxic enzyme.

Tips for single‐port laparoscopic cholecystectomy

Single‐port laparoscopic cholecystectomy (SPLC) is an emerging technique and gaining increased attention by its superiority in cosmesis. A 1.5‐cm vertical transumbilical incision is used for the single port, followed by the glove method. Indications for SPLC are the same as those for standard 4‐port laparoscopic cholecystectomy, including patients with morbid obesity, previous upper abdominal surgery, severe acute cholecystitis, or suspected presence of common bile duct stones. Some randomized controlled trials have shown negative results of SPLC regarding operative time, wound‐related complications, and postoperative pain. However, our retrospective analysis shows equivalent clinical outcomes among the two approaches in terms of postoperative pain and complications. In this context, SPLC can be a good option for gallbladder pathologies.

The Noninvasive Treatment for Sentinel Lymph Node Metastasis by Photodynamic Therapy Using Phospholipid Polymer as a Nanotransporter of Verteporfin

Aim. The usefulness of photodynamic therapy (PDT) for treating sentinel lymph node (SLN) metastasis was evaluated. Materials and Methods. Verteporfin, a hydrophobic photosensitizer, forms a soluble aggregate with poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB). The concentrations of verteporfin were determined by measuring the fluorescence emitted at 700 nm. Seven days after the inoculation of A431 cells at the forearm of BALB/c nude mice, PMB-verteporfin was injected at dorsum manus and 75 J of light energy was delivered for 1 minute. Fifty-three mice were randomly assigned to the combination of PMB-verteporfin injection and light exposure, light exposure alone, PMB-verteporfin injection alone, and no treatment groups. Ten days after PDT, brachial lymph nodes, which were considered as SLNs, were harvested and evaluated. Results. The concentration of verteporfin in SLN was significantly higher than other organs. The combination of PMB-verteporfin injection and light exposure group significantly reduced the SLN metastasis (13%) comparing with no treatment group (52%), light exposure alone group (57%), and PMB-verteporfin injection alone group (46%). Conclusions. These data suggested that PDT using PMB as a nanotransporter of verteporfin could be a minimally invasive treatment of SLN metastasis in breast cancer and represent a potential alternative procedure to SLNB.

Single-Port Transumbilical Laparoscopic Excision of Retroperitoneal Schwannoma Mimicking a Nonfunctional Endocrine Tumor in the Body of the Pancreas: A Case Report

Schwannomas are benign tumors that arise from neural sheath Schwann cells. Solitary benign schwannoma is generally located in the head and neck and is a rare neoplasm among the tumors of the retroperitoneal space. Reports of laparoscopic excision of retroperitoneal schwannomas have recently been on the increase. However, few cases of single-port laparoscopic excision of these tumors have been reported. Moreover, there are no reports of single-port excision of schwannomas attached to the body of pancreas and around the splenic vessels. This is the first report of a schwannoma lying adjacent to the body of the pancreas between the splenic artery and vein that was excised by single-port laparoscopic surgery. The most notable aspect of our procedure is the use of bipolar forceps. Single-port laparoscopic excision using bipolar forceps is a feasible and safe procedure for retroperitoneal solitary tumors, even when they are close to the splenic artery and vein.

Impact of obesity on surgical outcome after single-incision laparoscopic cholecystectomy

Introduction: Single-incision laparoscopic cholecystectomy (SILC) is widely used as a treatment option for gallbladder disease. However, obesity has been considered a relative contraindication to this approach due to more advanced technical difficulties. The aim of this report was to review our experience with SILC to evaluate the impact of body mass index (BMI) on the surgical outcome. Patients and Methods: Between May 2009 and February 2013, 237 patients underwent SILC at our institute. Pre- and post-operative data of the 17 obese patients (O-group) (BMI ≥30 kg/m2) and 220 non-obese patients (NO-group) (BMI <29.9 kg/m2) were compared retrospectively. SILC was performed under general anaesthesia, using glove technique. Indications for surgery included benign gallbladder disease, except for emergent surgeries. Results: Mean age of patients was significantly higher in the NO-group than O-group (58.9 ± 13.5 years vs. 50.8 ± 14.0 years, P = 0.025). SILC was successfully completed in 233 patients (98.3%). Four patients (1.7%) in the NO-group required an additional port, and one patient was converted to an open procedure. The median operative time was 70 ± 25 min in the NO-group and 75.2 ± 18.3 min in the O-group. All complications were minor, except for one case in the NO-group that suffered with leakage of the cystic duct stump, for which endoscopic nasobiliary drainage was need. Conclusion: Our findings show that obesity, intended as a BMI ≥30 kg/m2, does not have an adverse impact on the technical difficulty and post-operative outcomes of SILC. Obesity-related comorbidities did not increase the risks for SILC.

Transumbilical glove port: A cost-effective method for single-incision laparoscopic hepatectomy

Objectives: Emerging concepts of “reduced port surgery” have gained considerable attention from laparoscopic surgeons, including the field of liver resection. To date, 86 cases of single-incision laparoscopic hepatectomy (SILH) have been reported, with commercially available access devices being used in most of these cases. We report herein a use of homemade transumbilical glove port for SILH. Methods: A 39-year-old woman represented giant hepatic hemangioma (9-cm in size) located at the left lateral segment (S2/3). Partial hepatectomy was performed by the glove method via single port access with conventional laparoscopic bipolar forceps, grasper and scissors without the need of any single-port specific devices. Results: The operative time was 77 minutes, and intraoperative blood loss was 50 mL. The postoperative course was uneventful. Conclusions: Glove method not only has significant advantages in terms of cost, but also is superior in its versatility, allowing wider range of movements compared to conventional access devices. Taking in consideration its cost effectiveness and versatility, glove method may be a good option for SILH.

Abstract 2891: Photodynamic therapy using PMB polymer as a new nanotransporter of verteporfin for the treatment of lymph node metastasis in breast cancer

[Introduction] Although axillary lymph node dissection (ALND) has been part of breast cancer surgery, the impact of ALND on survival of breast cancer is still to be elucidated. At the same time ALND is associated with several complications such as lymphedema, seroma formation and shoulder dysfunction. Therefore, the development of minimally invasive procedure alternative to ALND is necessary. Photodynamic therapy (PDT) is a noninvasive optical therapeutic method in which the topical or systemic delivery of photosensitizer is followed by irradiation with broadband red light. Despite advantages such as longer wave length and a short photosensitivity period, verteporfin, a hydrophobic photosensitizer, has not yet been applied in cancer treatment. Previously, we have reported that PMB polymer forms a stable aggregate in water that can enhance the solubility of verteporfin, and PDT using a PMB-verteporfin complex is a promising anticancer therapy (Cancer Biotherapy and Radiopharmaceuticals 2011, Epub ahead of print). In this study, the efficacy of PDT using PMB polymer as a new nanotransporter of verteporfin for the treatment of lymph node metastasis was evaluated.[Materials and Methods]To develop a murine lymph node metastasis model, 5x105 human epithelial carcinoma A431 cells with stable expression of GFP were injected to the forearm of BALB/c nude mice. PMB polymer and verteporfin were mixed at the ratio of 25:1, and sonicated to make the PMB-verteporfin aggregate. Seven days after inoculation of cancer cells, PMB-verteporfin aggregate or PMB polymer alone was injected to the forearm of BALB/c nude mice. The concentation of verteporfin in lymph node was determined by measuring the fluorescence emitted at 700 nm (with excitation at 430 nm) using a microplate reader (BioTek, Vermont, USA). One hour after injection of aggregate or PMB alone, 75 J of light energy was delivered using a 640 nm diode laser for a total treatment time of 1 minute. Mice were randomly assigned to the combination of PMB-verteporfin inpjection and light exposure, light exposure alone, PMB-verteporfin injection alone, and PMB injection alone. Ten days after PDT, lymph nodes were harvested to evaluate metastasis by stereoscopic fluorescence microscope. [Results] Concentration of verteporfin was 23.9µg/g tissue in brachial and 9.5µg/g tissue in axillary lymph node. Lymph node metastasis rates of combination of PMB-verteporfin injection and light exposure group, light exposure group, PMB-verteporfin injection group, and PMB injection group were 12.5%, 57.1%, 33.3% and 56.3%, respectively. [Conclusion] These data suggested that PDT using PMB polymer as a new nanotransporter of verteporfin could be a minimally invasive treatment of lymph node metastasis in breast cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2891. doi:1538-7445.AM2012-2891