Publications by authors named "Jun Yamamoto"

124 Publications

Effects of synthetic sex steroid hormone exposures on gonadal sex differentiation and dynamics of a male-related gene, Gonadal soma-derived factor (Gsdf) and an estrogen up-regulated gene, Choriogenine-H (ChgH) gene expression in the euryhaline Javafish medaka, Oryzias javanicus, based on genetic sexes.

Chemosphere 2021 Jul 12;274:129893. Epub 2021 Feb 12.

Laboratory of Molecular Reproductive Biology, Institute for Environmental Sciences, University of Shizuoka, Shizuoka, 422-8526, Japan; Department of Environmental Life Sciences, School of Food and Nutritional Sciences, University of Shizuoka, Shizuoka, 422-8526, Japan. Electronic address:

To clarify the basal aspects of sexual development in Javafish medaka, Oryzias javanicus (ZZ/ZW), a model marine species for ecotoxicity testing, we examined the details of gonadal sex differentiation and exogenous sex hormone-dependent sex reversals using genetic sex-linked DNA markers. Sex differences in germ cell numbers were observed at 5 days post hatching (dph), in which there was a significant increase in the germ cells of ZW. In ZW, diplotene oocytes and the ovarian cavity appeared at approximately 10, and 30 dph, respectively. In ZZ, spermatogonial proliferation was observed at approximately 20 dph. A ZZ-dominant expression of Gonadal soma-derived factor (Gsdf) mRNA was detected before hatching. The exposure of embryos to 17α-ethinylestradiol (EE2; 0.1, 1, 10 ng/mL) did not cause sex reversals in most cases. However, EE2 exposures led to significant Choriogenin-H (ChgH) mRNA expression, an estrogen up-regulated gene, in all fry; these exposures did not suppress Gsdf expression in ZZ fry. The exposure of embryos to 17α-methyltestosterone (MT; 0.1, 1, 10 ng/mL) caused sex reversals but only at low frequencies in ZW and ZZ fish. Although the 10 ng/mL MT exposure was accompanied by induction of significant Gsdf expression in ZW fry, induction of ChgH expression was also observed in several fry. Together, the present study indicates for the first time that male-dominant sexual dimorphic expression of Gsdf precedes the first morphological sex difference, i.e., the sex difference in germ cell number, and results strongly suggest that exogenous sex hormone-dependent sex reversal is not induced easily in O. javanicus.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2021.129893DOI Listing
July 2021

[Cervical Abscess after Surgery for Subglottic Granuloma due to Suture Thread Used at Thyroplasty with Arytenoid Adduction].

Kyobu Geka 2021 Feb;74(2):116-119

Department of Thoracic Surgery, Eiju General Hospital, Tokyo, Japan.

A 83-year-old man underwent thyroplasty with arytenoid adduction for right recurrent laryngeal nerve palsy 1 year ago. He had been suffering from hemosputum and cough for last 2 months, and was referred to our hospital for medical examination. Laryngoscopy and neck computed tomography showed subglottic nodule. No evidence of malignancy was noted by a transbronchial biopsy of subglottic nodule. Since subglottic nodule grew rapidly during 2 months observation period, subglottic nodule resection was performed by bronchoscope. Histopathologic examination revealed that the tumor was suture granuloma with no evidence of malignancy. Cervical abscess as a complication of subglottic suture granuloma resection was occurred, because of suture material for arytenoid adduction and the injury of mucous membrane for removing the granuloma with the fenestration of thyroid cartilage for thyroplasty.
View Article and Find Full Text PDF

Download full-text PDF

Source
February 2021

A Novel Color-Coded Liver Metastasis Mouse Model to Distinguish Tumor and Adjacent Liver Segment.

J Surg Res 2021 Apr 10;264:327-333. Epub 2021 Apr 10.

Department of Surgery, University of California San Diego, San Diego, California; Department of Surgery, VA San Diego Healthcare System, San Diego, California. Electronic address:

Background: It is difficult to distinguish between a tumor and its liver segment with traditional use of indocyanine green (ICG) alone. In the present study, a method was used to limit ICG to the liver segment adjacent to a tumor. A spectrally-distinct fluorescently-labeled tumor-specific antibody against human carcinoembryonic antigen-related cell-adhesion molecules was used to label the metastatic tumor in a patient-derived orthotopic xenograft mouse model to enable color-coded visualization and distinction of a colon-cancer liver metastases and its adjacent liver segment.

Materials And Methods: Nude mice received surgical orthotopic implantation in the liver of colon-cancer liver metastases derived from two patients. An anti- carcinoembryonic antigen-related cell-adhesion molecules monoclonal antibody (mAb 6G5j) was conjugated to a near-infrared dye IR700DX (6G5j-IR700DX). After three weeks, mice received 6G5j-IR700DX via tail-vein injection 48 hours before surgery. ICG was intravenously injected after ligation of the left or left lateral Glissonean pedicle resulting in labeling of the segment with preserved blood-flow in the liver. Imaging was performed with the Pearl Trilogy and FLARE Imaging Systems.

Results: The metastatic liver tumor had a clear fluorescence signal due to selective tumor targeting by 6G5j-IR700DX, which was imaged on the 700 nm channel. The adjacent liver segment, with preserved blood-flow in the liver, had a clear fluorescence ICG 800 nm signal, while the left or left lateral segment had no fluorescence signal. Overlay of the images showed clear color-coded differentiation between the tumor fluorescing at 700 nm and the adjacent liver segment fluorescing at 800 nm.

Conclusions: Color-coding of a liver tumor and uninvolved liver segment has the potential for improved liver resection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jss.2021.02.022DOI Listing
April 2021

Eribulin Inhibits Osteosarcoma in a Clinically-accurate Bone-tumor-insertion PDOX Mouse Model.

Anticancer Res 2021 Apr;41(4):1779-1784

AntiCancer Inc, San Diego, CA, U.S.A.;

Background/aim: Osteosarcoma is a rare type of bone cancer that affects mostly children and adolescents. First-line chemotherapy for osteosarcoma has not been improved for many decades. Eribulin has been used to treat breast cancer and liposarcoma in the clinic.

Materials And Methods: A patient-derived orthotopic xenograft (PDOX) mouse model of osteosarcoma was established by tumor insertion within the tibia. This model more closely mimics osteosarcoma in clinical settings and was used to test the efficacy of eribulin. Tibia-insertion osteosarcoma PDOX mouse models were randomized into two groups: a control group (n=4) and an eribulin-treatment group (n=5). Mice were treated for fourteen days, four weeks after initial implantation. Tumor size and body weight were measured, and tumor histology was examined.

Results: Significant tumor growth inhibition (p=0.044) was observed in mice treated with eribulin compared to the control group. Histology demonstrated necrosis in the eribulin-treated tumors. There was no body-weight loss in the treated mice.

Conclusion: Eribulin may be a clinically-effective, off-label chemotherapy for recalcitrant osteosarcoma that has failed first- and second-line therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14943DOI Listing
April 2021

Oral-recombinant Methioninase Converts an Osteosarcoma from Docetaxel-resistant to -Sensitive in a Clinically-relevant Patient-derived Orthotopic-xenograft (PDOX) Mouse Model.

Anticancer Res 2021 Apr;41(4):1745-1751

AntiCancer Inc, San Diego, CA, U.S.A.;

Background/aim: Osteosarcoma is the most frequent malignant bone tumor. Failure of first-line therapy results in poor prognosis of osteosarcoma. In the present report, we examined the efficacy of the combination of oral recombinant methioninase (o-rMETase) and docetaxel (DOC) on an osteosarcoma patient-derived orthotopic xenograft (PDOX) mouse model.

Materials And Methods: Osteosarcoma-PDOX models were established by tumor insertion within the tibia of nude mice. The osteosarcoma PDOX models were randomized into four groups (4-5 mice per group): control; o-rMETae alone; DOC alone; o- rMETase combined with DOC. The treatment period was 3 weeks.

Results: The combination of o-rMETase and DOC showed significant efficacy compared to the control group (p=0.03). In contrast, there was no significant efficacy of o-rMETase alone or DOC alone (p=0.65, 0.60, respectively).

Conclusion: o-rMETase converted an osteosarcoma PDOX from DOC-resistant to -sensitive. This combination therapy may be effective against recalcitrant osteosarcoma and other recalcitrant cancers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14939DOI Listing
April 2021

Oral recombinant methioninase combined with paclitaxel arrests recalcitrant ovarian clear cell carcinoma growth in a patient-derived orthotopic xenograft (PDOX) nude-mouse model.

Cancer Chemother Pharmacol 2021 Jul 25;88(1):61-67. Epub 2021 Mar 25.

AntiCancer, Inc, 7917 Ostrow Street, San Diego, 92111, CA, USA.

Purpose: Advanced ovarian clear cell carcinoma (OCCC) is a recalcitrant disease, often resistant to the first-line platinum-based therapy. Using a novel patient-derived orthotopic xenograft (PDOX) nude-mouse model of OCCC, we tested whether oral-recombinant methioninase (o-rMETase) could enhance the efficacy of paclitaxel (PTX).

Methods: The OCCC PDOX model was established and passaged in nude mice. The OCCC PDOX models were randomized into 5 groups. G1: untreated control; G2: paclitaxel (PTX) (20 mg/kg, intraperitoneal (i.p.) injection, weekly); G3: o-rMETase (100 units, oral, daily); G4: PTX (20 mg/kg, i.p. injection, weekly) + carboplatinum (CBDCA) (40 mg/kg, i.p. injection weekly); G5: PTX (20 mg/kg, i.p. injection, weekly) + o-rMETase (100 units, oral, daily). The treatment period was 2 weeks.

Results: The combination of PTX and o-rMETase arrested OCCC tumor growth (relative tumor volume: 1.09 ± 0.63 (mean ± SD)) compared with the untreated control (relative tumor volume: 3.92 ± 1.04 (mean ± SD)) (p < 0.0001). There was no significant difference in relative tumor volume between PTX plus o-rMETase and PTX plus CBDCA (relative tumor volume: 1.39 ± 0.37 (mean ± SD)) (p = 0.93).

Conclusion: PTX plus o-rMETase arrested the OCCC tumor growth. o-rMETase is readily administered and can greatly enhance first-line therapy of a recalcitrant cancer. The novel and effective treatment strategy in the present report has future clinical potential for patients with OCCC, especially for patients who cannot well tolerate platinum-based therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00280-021-04261-xDOI Listing
July 2021

Combination Methionine-methylation-axis Blockade: A Novel Approach to Target the Methionine Addiction of Cancer.

Cancer Genomics Proteomics 2021 Mar-Apr;18(2):113-120

AntiCancer, Inc., San Diego, CA, U.S.A.;

Background/aim: Cancers are selectively sensitive to methionine (MET) restriction (MR) due to their addiction to MET which is overused for elevated methylation reactions. MET addiction of cancer was discovered by us 45 years ago. MR of cancer results in depletion of S-adenosylmethionine (SAM) for transmethylation reactions, resulting in selective cancer-growth arrest in the late S/G-phase of the cell cycle. The aim of the present study was to determine if blockade of the MET-methylation axis is a highly-effective strategy for cancer chemotherapy.

Materials And Methods: In the present study, we demonstrated the efficacy of MET-methylation-axis blockade using MR by oral-recombinant methioninase (o-rMETase) combined with decitabine (DAC), an inhibitor of DNA methylation, and an inhibitor of SAM synthesis, cycloleucine (CL). We determined a proof-of-concept of the efficacy of the MET-methylation-axis blockade on a recalcitrant undifferentiated/unclassified soft-tissue sarcoma (USTS) patient-derived orthotopic xenograft (PDOX) mouse model.

Results: The o-rMETase-CL-DAC combination regressed the USTS PDOX with extensive cancer necrosis.

Conclusion: The new concept of combination MET-methylation-axis blockade is effective and can now be tested on many types of recalcitrant cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/cgp.20246DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7943212PMC
August 2020

Reversion from Methionine Addiction to Methionine Independence Results in Loss of Tumorigenic Potential of Highly-malignant Lung-cancer Cells.

Anticancer Res 2021 Feb;41(2):641-643

AntiCancer Inc, San Diego, CA, U.S.A.;

Background/aim: Methionine addiction, a fundamental and general hallmark of cancer, is due to the excess use of methionine for transmethylation, and is described as the Hoffman-effect. Methionine-addicted cancer cells can revert at low frequency to methionine independence when selected under methionine-restriction. We report here that highly-malignant methionine-addicted H460 human lung-cancer cells, when selected for methionine independence, have greatly-reduced tumorigenic potential.

Materials And Methods: Methionine-addicted H460 parental cancer cells and methionine-independent revertant H460-R1 cells were injected in nude mice subcutaneously.

Results: When the parental H460 methionine-addicted cells were injected in nude mice at 2.5×10, 1×10 and 5×10, the cells could form tumors. In contrast, the H460-R1 methionine-independent revertant cells could not form tumors when the above-listed cell numbers were injected in nude mice.

Conclusion: There is a tight linkage between methionine addiction and malignancy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14815DOI Listing
February 2021

Summary of reference chemicals evaluated by the fish short-term reproduction assay, OECD TG229, using Japanese Medaka, Oryzias latipes.

J Appl Toxicol 2021 Jan 24. Epub 2021 Jan 24.

Nanobioscience, Yokohama City University, Yokohama, Japan.

Under the Organisation for Economic Co-operation and Development (OECD), the Ministry of the Environment of Japan (MOE) added Japanese medaka (Oryzias latipes) to the test guideline fish short-term reproduction assay (FSTRA) developed by the United States Environmental Protection Agency (US EPA) using fathead minnow (Pimephales promelas). The FSTRA was designed to detect endocrine disrupting effects of chemicals interacting with the hypothalamic-pituitary-gonadal axis (HPG axis) such as agonists or antagonists on the estrogen receptor (Esr) and/or the androgen receptor (AR) and steroidogenesis inhibitors. We conducted the FSTRA with Japanese medaka, in accordance with OECD test guideline number 229 (TG229), for 16 chemicals including four Esr agonists, two Esr antagonists, three AR agonists, two AR antagonists, two steroidogenesis inhibitors, two progesterone receptor agonists, and a negative substance, and evaluated the usability and the validity of the FSTRA (TG229) protocol. In addition, in vitro reporter gene assays (RGAs) using Esr1 and ARβ of Japanese medaka were performed for the 16 chemicals, to support the interpretation of the in vivo effects observed in the FSTRA. In the present study, all the test chemicals, except an antiandrogenic chemical and a weak Esr agonist, significantly reduced the reproductive status of the test fish, that is, fecundity or fertility, at concentrations where no overt toxicity was observed. Moreover, vitellogenin (VTG) induction in males and formation of secondary sex characteristics (SSC), papillary processes on the anal fin, in females was sensitive endpoints to Esr and AR agonistic effects, respectively, and might be indicators of the effect concentrations in long-term exposure. Overall, it is suggested that the in vivo FSTRA supported by in vitro RGA data can adequately detect effects on the test fish, O. latipes, and probably identify the mode of action (MOA) of the chemicals tested.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jat.4104DOI Listing
January 2021

A Novel Procedure for Orthotopic Tibia Implantation for Establishment of a More Clinical Osteosarcoma PDOX Mouse Model.

In Vivo 2021 Jan-Feb;35(1):105-109

AntiCancer Inc, San Diego, CA, U.S.A.;

Background/aim: Osteosarcoma is a rare type of malignancy that affects mostly children and adolescents. A new procedure was designed to create an improved patient-derived orthotopic xenograft (PDOX) mouse model of osteosarcoma that more closely mimics osteosarcoma in clinical settings. Previous osteosarcoma PDOX models involved implanting a tumor fragment near the femur of nude mice in a space created by separating muscle.

Materials And Methods: A hole was created in the tibia of nude mice and an osteosarcoma tumor fragment was implanted directly into the bone.

Results: This procedure resulted in tumor growth in the bone similar to osteosarcoma tumors found in clinical patients.

Conclusion: The establishment ratio for this procedure is 80% making it a practical and clinically-relevant model for screening effective therapies for osteosarcoma patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.12237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7880751PMC
November 2020

Triple-Methyl Blockade With Recombinant Methioninase, Cycloleucine, and Azacitidine Arrests a Pancreatic Cancer Patient-Derived Orthotopic Xenograft Model.

Pancreas 2021 01;50(1):93-98

Department of Surgery, Graduate School of Medicine, Tohoku University, Sendai, Japan.

Objectives: Methionine addiction is a fundamental and general hallmark of cancer caused by enhanced methyl flux. In the present study, we effected a novel methionine-methylation blockade to target a patient-derived orthotopic xenograft model of pancreatic cancer.

Methods: The pancreatic cancer patient-derived orthotopic xenograft mouse models were randomized into 6 groups of 8 mice each and treated for 2 weeks: untreated control; azacitidine; oral recombinant methioninase (o-rMETase); o-rMETase plus cycloleucine; o-rMETase plus cycloleucine plus azacitidine (triple-methyl blockade therapy); and gemcitabine (positive control).

Results: Triple-methyl blockade therapy arrested tumor growth (mean relative tumor volume, 1.03 [standard deviation, 0.36]) and was significantly more effective compared with azacitidine (P = 0.0001); o-rMETase (P = 0.007); or o-rMETase plus cycloleucine (P = 0.04). Gemcitabine alone also inhibited but did not arrest tumor growth (mean relative tumor volume, 1.50 [standard deviation, 0.30]). The percentage of cancer cells that were negative for 5-methylcytosine staining in immunohistochemistry, indicating reduction of DNA methylation, increased with triple-methyl blockade therapy (37.5%), compared with gemcitabine (1.8%); o-rMETase (2.8%); azacitidine (9.0%); or o-rMETase plus cycloleucine (10.6%).

Conclusions: This new concept of triple-methyl blockade therapy has clinical potential for pancreatic cancer, which is currently a recalcitrant disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MPA.0000000000001709DOI Listing
January 2021

A Universal Gelfoam 3-D Histoculture Method to Establish Patient-derived Cancer Cells (3D-PDCC) Without Fibroblasts from Patient-derived Xenografts.

Anticancer Res 2020 Dec;40(12):6765-6768

AntiCancer Inc, San Diego, CA, U.S.A.

Background/aim: The direct placement of patient tumors in 2-D culture on plastic or glass surfaces has inhibited the establishment of patient-derived cancer cells (PDCCs). The aim of the present study was to develop universal and efficient methods to prepare PDCCs.

Materials And Methods: Fragments of patient-derived xenograft (PDX) tumors established form colon cancer liver metastasis (1 mm) were placed on Gelfoam and cultured in DMEM.

Results: PDX tumor fragments were cultured on Gelfoam. Cancer cells migrated from the explant and formed distinct 3-D structures in the Gelfoam. Each of the three PDCCs showed a distinct morphology. The cultures were essentially all cancer cells without fibroblasts, the opposite of what usually occurs in 2-D culture on plastic or glass. Gelfoam cultures could be readily passaged from one Gelfoam cube to anothers suggesting indefinite culture potential.

Conclusion: A potentially universal method to establish PDCC using PDX tumors and 3-D Gelfoam histoculture was developed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14699DOI Listing
December 2020

Relationship between psychosocial factors and objective physical function in special needs school staff members suffering from low back pain.

Ind Health 2021 Feb 21;59(1):54-62. Epub 2020 Nov 21.

Department of Public Health, Hyogo College of Medicine, Japan.

Physical function impairment in patients with low back pain (LBP) occurs due to the influence of psychosocial factors. Only a few studies have objectively evaluated physical function. We aimed to objectively assess the physical functions of individuals subjects with LBP, and clarify the association between physical function and psychosocial factors. We enrolled 411 individuals with LBP working in special needs schools. We examined their degree of pain, and the psychosocial factors strength through the STarT Back Tool, which categorized them into the low-risk, medium-risk, and high-risk groups. We assessed their abdominal muscle endurance, lower limb muscle strength, and hip joint flexibility. The relationships between these physical functions and psychosocial factors were analyzed by logistic regression models. Those in the high-risk group had significantly lower abdominal muscle and lower limb muscle strength (p<0.001). After adjusting for confounding factors, the odds ratios of the high-risk compared to the low-risk group for low abdominal muscle endurance, lower limb muscle strength, and restricted right and left Straight Leg Raising were 5.47, 3.14, 2.65, and 3.12, respectively (95% CIs: 2.35-12.74, 1.43-6.89, 1.08-6.55, and 1.20-8.11, respectively). Therefore, the low physical function observed in the high-risk group was associated with their psychosocial factors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2486/indhealth.2020-0169DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7855674PMC
February 2021

A Non-invasive Imageable GFP-expressing Mouse Model of Orthotopic Human Bladder Cancer.

In Vivo 2020 Nov-Dec;34(6):3225-3231

AntiCancer, Inc., San Diego, CA, U.S.A.

Background/aim: A more realistic mouse model of bladder cancer is necessary to develop effective drugs for the disease. Tumor models enhanced by bright fluorescent-reporter genes to follow the disease in real-time would enhance the ability to accurately predict the efficacy of various therapeutics on this particularly-malignant human cancer.

Materials And Methods: A highly-fluorescent green fluorescent protein (GFP)-expressing bladder cancer model was orthotopically established in nude mice using the UM-UC-3 human bladder-cancer cell line (UM-UC-3-GFP). Fragments from a subcutaneous tumor of UM-UC-3-GFP were surgically implanted into the nude mouse bladder. Non-invasive and intra-vital fluorescence imaging was obtained with a simple imaging box.

Results: The GFP-expressing orthotopic bladder tumor was imaged in real-time non-invasively as well as intra-vitally, with the two methods correlating at r=0.99.

Conclusion: This is the first non-invasive-fluorescence-imaging orthotopic model of bladder cancer and can be used for rapidly screening novel effective agents for this recalcitrant disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.12158DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7811621PMC
August 2020

Response of Triple-negative Breast Cancer Liver Metastasis to Oral Recombinant Methioninase in a Patient-derived Orthotopic Xenograft (PDOX) Model.

In Vivo 2020 Nov-Dec;34(6):3163-3169

AntiCancer Inc, San Diego, CA, U.S.A.

Background/aim: The aim of this study was to establish a patient-derived orthotopic xenograft (PDOX) mouse model of liver metastasis of triple-negative breast cancer (TNBC) and examine the efficacy of oral recombinant methioninase (o-rMETase) on the liver metastasis.

Materials And Methods: TNBC from a patient was implanted in the left hepatic lobe of nude mice to simulate liver metastasis in a PDOX model. Ten days later, all mice underwent laparotomy to measure tumor size and were randomized to three groups: control; o-rMETase 100 U once daily (qd); and o-rMETase 200 U qd. After 9 days of treatment, all mice were sacrificed.

Results: At the end of the treatment period for the liver metastasis, the size of liver metastases was 372.6 mm in the control group; 160.0 mm in the o-rMETase 100 U group; and 245.3 mm in the o-rMETase 200 U group. All mice had ascites and 12 out of 14 mice in all groups had mesenteric lymph-node metastasis, as re-metastasis. The mean body-condition score was 1.5 in the control group; 2.4 in the o-rMETase 100 U group; and 2.6 in the o-rMETase 200 U group (control group vs. o-rMETase 200 U group, p<0.05).

Conclusion: The TNBC liver metastasis was highly aggressive resulting in re-metastasis and ascites. o-rMETase tended to inhibit the liver metastasis and significantly improved the mouse body-condition score. This new PDOX model of TNBC liver metastasis will be useful for identifying effective agents for this recalcitrant disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.12151DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7811664PMC
July 2020

Ligation Method to Specifically Label a Liver Segment With Indocyanine Green in an Orthotopic Nude-Mouse Liver-Metastasis Model.

In Vivo 2020 Nov-Dec;34(6):3159-3162

Department of Surgery, University of California San Diego, San Diego, CA, U.S.A.

Background/aim: The visualization of hepatic segments with indocyanine green (ICG) fluorescence can aid in anatomic liver resection. The present study aimed to develop a method to specifically label an hepatic segment in a nude mouse model with liver metastasis.

Materials And Methods: An orthotopic mouse model was established by surgical orthotopic implantation (SOI) of a patient-derived colon-cancer liver metastasis in the left lobe of the liver. Three weeks after SOI, the left Glissonean pedicle was ligated and 10 μg ICG was administrated intravenously. Images were obtained with the Pearl Trilogy Imaging System.

Results: All mice expressed an 800 nm signal from ICG on the right lobe of the liver. The left lobe of the liver, in which the tumor was located, showed no fluorescence and had ischemia due to successful ligation of the Glissonean pedicle.

Conclusion: The ligation of the Glissonean pedicle enables specific liver-segment labeling with ICG, which has potential clinical application for liver metastasectomy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.12150DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7811678PMC
July 2020

Sutureless Surgical Orthotopic Implantation Technique of Primary and Metastatic Cancer in the Liver of Mouse Models.

In Vivo 2020 Nov-Dec;34(6):3153-3157

Department of Surgery, University of California San Diego, San Diego, CA, U.S.A.

Background/aim: Surgical orthotopic implantation (SOI) is used to establish patient-derived orthotopic xenograft (PDOX) and other orthotopic mouse models. Orthotopic liver models can be challenging, as the liver parenchyma is prone to bleeding. The present report describes a sutureless method to implant tumors in the liver that reduces bleeding and procedural time.

Materials And Methods: Human HCC cell-line (Huh-7-GFP) and CM2, a patient-derived colon-cancer liver metastasis, were used for sutureless SOI of tumor fragments in the liver of nude mice. A small cavity was formed on the liver surface. A solitary tumor fragment was implanted in the cavity without suturing to create hemostasis.

Results: Six weeks after sutureless SOI, the tumor volume of Huh-7-GFP (n=5) was 584.41±147.64 mm and the tumor volume of CM2 (n=5) was 1336.54±1038.20 mm The engraftment rate was 100%.

Conclusion: This novel method for establishing orthotopic liver-implantation mouse models is suitable for studies of liver cancer and liver metastases due to its simple procedure and potential high engraftment rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.12149DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7811661PMC
July 2020

Ischemia reperfusion-induced metastasis is resistant to PPARγ agonist pioglitazone in a murine model of colon cancer.

Sci Rep 2020 10 29;10(1):18565. Epub 2020 Oct 29.

AntiCancer Inc, 7917 Ostrow St, San Diego, CA, 92111, USA.

Ischemia reperfusion injury (IRI) during liver-metastasis resection for treatment of colon cancer may increase the risk of further metastasis. Peroxisome proliferator-activated receptor-γ (PPARγ) activation has been observed to exert a protective effect against IRI and IRI-induced metastasis of hepatocellular carcinoma. The present study aimed to investigate the effect of the PPARγ agonist pioglitazone on tumor metastasis and liver injury following IRI in a mouse model of colon cancer. Pioglitazone (30 mg/kg weight) was administered orally 1.5 h before and 2 h after the initiation of ischemia and was orally administrated daily to mice from day 0-21. SL4-cancer cells expressing red fluorescent protein (SL4-RFP) (1 × 10) were injected into the spleen. Fifteen minutes after injection, the hepatoduodenal ligament was clamped with a vessel clip, and released 5 min later. Liver, blood and tumor samples were taken from mice in order to determine if inflammation was induced by IRI. The effect of pioglitazone on liver metastasis was assessed. Furthermore, the effect of pioglitazone to control the inflammatory response during IRI progression was examined. Liver metastasis along with MMP-9 activation and the production of inflammatory cytokines were resistant to pioglitazone. Our results indicate that liver metastasis and associated inflammation in mice were resistant to pioglitazone.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-75210-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7596558PMC
October 2020

Oral Recombinant Methioninase Sensitizes a Bladder Cancer Orthotopic Xenograft Mouse Model to Low-dose Cisplatinum and Prevents Metastasis.

Anticancer Res 2020 Nov;40(11):6083-6091

AntiCancer, Inc., San Diego, CA, U.S.A.

Background/aim: The aim of the study was to determine if oral recombinant methioninase (o-rMETase) can sensitize an orthotopic bladder tumor in nude mice to low-dose cisplatinum (CDDP).

Materials And Methods: The green fluorescent protein (GFP)-expressing UM-UC-3-GFP bladder cancer was surgically orthotopically implanted (SOI) to the bladder in nude mice. The treatment was initiated when the primary tumor volume reached 100 mm Mice were assigned to 3 groups: G1: Saline vehicle (0.1 ml per mouse, oral, twice per day); G2: low-dose CDDP (0.5 mg/kg, intraperitoneal twice per week); G3: o-rMETase + low-dose CDDP (100 units per mouse, oral, twice per day + 0.5 mg/kg, intraperitoneal twice per week, respectively). Tumor volume and body weight were measured twice per week. The expression of Ki-67 was detected by immunohistochemistry to evaluate cell proliferation.

Results: The combination of o-rMETase and low-dose CDDP increased inhibition efficacy compared to low-dose CDDP monotherapy, on primary-tumor growth (p=0.032) and metastasis (p=0.002).

Conclusion: The combination of o-rMETase with low-dose CDDP has future clinical potential for bladder cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14629DOI Listing
November 2020

Histone methylation status of H3K4me3 and H3K9me3 under methionine restriction is unstable in methionine-addicted cancer cells, but stable in normal cells.

Biochem Biophys Res Commun 2020 12 3;533(4):1034-1038. Epub 2020 Oct 3.

AntiCancer Inc, 7917 Ostrow St, San Diego, CA, 92111, USA; Department of Surgery, University of California, San Diego, 9300 Campus Point Drive #7220, La Jolla, CA, 92037-7220, USA. Electronic address:

Methionine addiction is a fundamental and general hallmark of cancer. Methionine addiction prevents cancer cells, but not normal cells from proliferation under methionine restriction (MR). Previous studies reported that MR altered the histone methylation levels in methionine-addicted cancer cells. However, no study has yet compared the status of histone methylation status, under MR, between cancer cells and normal cells. In the present study, we compared the histone methylation status between cancer cells and normal fibroblasts of H3K4me3 and H3K9me3, using recombinant methioninase (rMETase) to effect MR. Human lung and colon cancer cell lines and human normal foreskin fibroblasts were cultured in control medium or medium with rMETase. The viability of foreskin fibroblasts was approximately 10 times more resistant to rMETase than the cancer cells in vitro. Proliferation only of the cancer cells ceased under MR. The histone methylation status of H3K4me3 and H3K9me3 under MR was evaluated by immunoblotting. The levels of the H3K4me3 and H3K9me3 were strongly decreased by MR in the cancer cells. In contrast, the levels of H3K4me3 and H3K9me3 were not altered by MR in normal fibroblasts. The present results suggest that histone methylation status of H3K4me3 and H3K9me3 under MR was unstable in cancer cells but stable in normal cells and the instability of histone methylation status under MR may determine the high methionine dependency of cancer cells to survive and proliferate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2020.09.108DOI Listing
December 2020

A Gemcitabine Plus 5-Fluorouracil Combination Inhibits Gastric-Cancer Liver Metastasis in a PDOX Model: A Novel Treatment Strategy.

Anticancer Res 2020 Oct;40(10):5393-5397

AntiCancer, Inc., San Diego, CA, U.S.A.

Background/aim: We established a new patient-derived orthotopic xenograft (PDOX) model of gastric cancer liver metastasis and evaluated the efficacy of a novel combination chemotherapy, gemcitabine (GEM) plus 5-fluorouracil (5-FU), compared to a standard regimen of oxaliplatinum (L-OHP) plus 5-FU on the liver metastasis.

Materials And Methods: Patient-derived gastric cancer was established in nude mice from the patient' s surgical tumor specimen. A single tumor fragment was implanted in the liver of nude mice. The mice with tumors were treated by GEM plus 5-FU or L-OHP plus 5-FU.

Results: GEM plus 5-FU or L-OHP plus 5-FU significantly and similarly inhibited tumor growth on the liver compared to the untreated control (p=0.007, p=0.02, respectively).

Conclusion: GEM plus 5-FU could be a novel future clinical alternative to L-OHP plus 5-FU in gastric cancer patients who cannot tolerate platinum drugs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14547DOI Listing
October 2020

Adjuvant Oral Recombinant Methioninase Inhibits Lung Metastasis in a Surgical Breast-Cancer Orthotopic Syngeneic Model.

Anticancer Res 2020 Sep;40(9):4869-4874

AntiCancer, Inc., San Diego, CA, U.S.A.

Background/aim: In the present study, we evaluated the efficacy of adjuvant administration of oral recombinant methioninase (o-rMETase) against recurrence and metastasis in a 4T1 murine breast-cancer syngeneic model.

Materials And Methods: 4T1 cells were orthotopically implanted into the 2nd mammary fat pad of BALB/c mice. The 4T1 orthotopic syngeneic models were randomized into 2 groups after primary tumor resection: untreated control and o-rMETase (100 units, oral, daily, 2 weeks).

Results: The frequency and extent of local recurrence were reduced by o-rMETase. The number of individual cancer cells and metastatic nodules on the lung surface was significantly lower in the o-rMETase-treated mice than the untreated control mice.

Conclusion: Adjuvant o-rMETase inhibited local recurrence and lung metastasis after primary tumor resection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14489DOI Listing
September 2020

Oral Methioninase Inhibits Recurrence in a PDOX Mouse Model of Aggressive Triple-negative Breast Cancer.

In Vivo 2020 Sep-Oct;34(5):2281-2286

AntiCancer Inc, San Diego, CA, U.S.A.

Background/aim: The aim of the study was to use a triple-negative breast cancer (TNBC) patient-derived orthotopic xenograft (PDOX) model to examine the efficacy of oral recombinant methioninase (o-rMETase) against this recalcitrant disease.

Materials And Methods: The TNBC tumor from a patient was implanted in the right 4 inguinal mammary fat pad of nude mice. Two weeks later, the mice underwent tumorectomy with grossly-negative surgical margins. Two days after tumorectomy the mice were divided in two groups: one control and one treated with o-rMETase.

Results: Tumors recurred in all mice. On day 11, the mean recurrent tumor volumes were 936.7 mm in the control group and 450.9 mm in the o-rMETase group (p<0.05). On day 15, the mean recurrent tumor volumes were 3392.5 mm in the control group and 1603.5 mm in the o-rMETase group. The mean recurrent tumor weights were 2.1 g in the control group and 1.1 g in the o-rMETase group on day 15.

Conclusion: o-rMETase is an effective adjuvant treatment for aggressive TNBC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.12039DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652477PMC
May 2020

Indocyanine Green Labels an Orthotopic Nude-Mouse Model of Very-Early Colon-Cancer Liver Metastases.

In Vivo 2020 Sep-Oct;34(5):2277-2280

Department of Surgery, University of California, San Diego, CA, U.S.A.

Background/aim: Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) is used to visualize colon-cancer liver metastases (CCLM) during surgery. The present study aimed to use ICG to visualize small CCLM in an orthotopic mouse model.

Materials And Methods: A 3-mm fragment of HT29 human colon cancer was implanted to the liver of 5 athymic nude mice (nu/nu). The Pearl Trilogy Small Animal Fluorescence Imaging system was used 24 h after intravenous (IV) injection of 0.025 mg (0.25 mg/ml) ICG.

Results: In four of the five mice, tumor fluorescence was detected. Small tumors (approximately 3 mm) were distinctly visualized with a minimal fluorescence liver signal, with a mean tumor to liver signal ratio of 1.81 (SD±0.167).

Conclusion: Small CCLM can be clearly identified by ICG fluorescence in an orthotopic nude-mouse model. This model is translatable to the clinic for the detection of occult early CCLM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.12038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652533PMC
May 2020

Oral recombinant methioninase increases TRAIL receptor-2 expression to regress pancreatic cancer in combination with agonist tigatuzumab in an orthotopic mouse model.

Cancer Lett 2020 11 31;492:174-184. Epub 2020 Jul 31.

AntiCancer Inc, San Diego, CA, USA; Department of Surgery, University of California, San Diego, CA, USA. Electronic address:

Methionine addiction is a fundamental and general hallmark of cancer. Gene expression analysis showed that methionine restriction (MR) of methionine-addicted cancer cells increases TNF-related apoptosis-induced ligand receptor-2 (TRAIL-R2) expression. Here, we determined the effects of MR on TRAIL-R2 targeted therapy in pancreatic cancer by the TRAIL-R2 agonist tigatuzumab. Human pancreatic cancer cell lines were cultured in control or methionine-free medium. The effects of MR on TRAIL-R2 expression and sensitivity to tigatuzumab were evaluated in vitro. An orthotopic pancreatic cancer mouse model was established to evaluate the efficacy of MR using oral recombinant methioninase (o-rMETase), and the efficacy of tigatuzumab and their combination. MR enabled tigatuzumab-induced apoptosis, by increasing TRAIL-R2 expression in pancreatic cancer cells in vitro. The protein expression level of the melanoma-associated antigen MAGED2, which reduces TRAIL-R2 expression, was decreased by MR. In the orthotopic pancreatic cancer mouse model, o-rMETase increased TRAIL-R2 expression level in the tumors and enabled the antitumor efficacy of tigatuzumab. MR, effected by o-rMETase, enabled the efficacy of the TRAIL-R2 agonist tigatuzumab by increasing TRAIL-R2 expression in pancreatic cancer. Our results suggest that o-rMETase has clinical potential for treating pancreatic cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.canlet.2020.07.034DOI Listing
November 2020

Structural transformations in tetravalent nematic shells induced by a magnetic field.

Soft Matter 2020 Sep;16(35):8169-8178

UMR No. 7083, CNRS, Gulliver, ESPCI Paris, PSL Research University, 10 Rue Vauquelin, 75005 Paris, France.

The role of applied fields on the structure of liquid crystals confined to shell geometries has been studied in past theoretical work, providing strategies to produce liquid crystal shells with controlled defect structure or valence. However, the predictions of such studies have not been experimentally explored yet. In this work, we study the structural transformations undergone by tetravalent nematic liquid crystal shells under a strong uniform magnetic field, using both experiments and simulations. We consider two different cases in terms of shell geometry and initial defect symmetry: (i) homogeneous shells with four s = +1/2 defects in a tetrahedral arrangement, and (ii) inhomogeneous shells with four s = +1/2 defects localized in their thinner parts. Consistently with previous theoretical results, we observe that the initial defect structure evolves into a bipolar one, in a process where the defects migrate towards the poles. Interestingly, we find that the defect trajectories and dynamics are controlled by curvature walls that connect the defects by pairs. Based on the angle between Bs, the local projection of the magnetic field on the shell surface, and n+½, a vector describing the defect orientations, we are able to predict the nature and shape of those inversion walls, and therefore, the trajectory and dynamics of the defects. This rule, based on symmetry arguments, is consistent with both experiments and simulations and applies for shells that are either homogeneous or inhomogeneous in thickness. By modifying the angle between Bs and n+½, we are able to induce, in controlled way, complex routes towards the final bipolar state. In the case of inhomogeneous shells, the specific symmetry of the shell allowed us to observe a hybrid splay-bend Helfrich wall for the first time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/d0sm00340aDOI Listing
September 2020

A Triple-negative Matrix-producing Breast Carcinoma Patient-derived Orthotopic Xenograft (PDOX) Mouse Model Is Sensitive to Bevacizumab and Vinorelbine, Regressed by Eribulin and Resistant to Olaparib.

Anticancer Res 2020 May;40(5):2509-2514

AntiCancer Inc, San Diego, CA, U.S.A.

Background/aim: Matrix-producing breast carcinoma (MPBC) is a rare and usually aggressive triple-negative breast cancer (TNBC). In this study, we determined drug sensitivity for a triple-negative MPBC, without BRCA mutations, in a patient-derived orthotopic xenograft (PDOX) model.

Materials And Methods: The MPBC PDOX model was established in the left 2 mammary gland of nude mouse by implantation of the patient tumor using surgical orthotopic implantation (SOI). We randomized MPBC PDOX mice into 5 groups (n=5 mice/per treatment group) when the tumor volume reached 80 mm: G1, control-no treatment; G2, bevacizumab [intra-peritoneal (i.p.), weekly, for 2 weeks]; G3, vinorelbine (i.p., weekly, for 2 weeks); G4, olaparib (oral., daily, for 2 weeks); G5, eribulin [intravenous (i.v.), weekly, for 2 weeks]. The mice in each treatment group were sacrificed on day 15. Tumor volume and body weight were measured once/week.

Results: The MPBC PDOX model was resistant to olaparib (p=0.22). The MPBC PDOX model treated with bevacizumab and vinorelbine showed significantly suppressed tumor growth compared to the untreated group (p=0.005 and 0.002, respectively). However, only eribulin regressed the tumor (p=0.0001). Eribulin was more effective than olaparib (p=0.0001), bevacizumab (p=0.0025) and vinorelbine (p=0.0061).

Conclusion: Eribulin has clinical potential as treatment for triple-negative MPBC patients that are resistant to a PARP inhibitor such as olaparib.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14221DOI Listing
May 2020

A Single Low Dose of Eribulin Regressed a Highly Aggressive Triple-negative Breast Cancer in a Patient-derived Orthotopic Xenograft Model.

Anticancer Res 2020 May;40(5):2481-2485

AntiCancer Inc, San Diego, CA, U.S.A.

Background/aim: In the present study, the breast cancer patient-derived orthotopic xenograft (PDOX) model was used to identify an effective drug for a highly aggressive triple negative breast cancer (TNBC).

Materials And Methods: The TNBC tumor from a patient was implanted in the right 4th inguinal mammary fat pad of nude mice to establish a PDOX model. Three weeks later, 19 mice were randomized into the untreated-control group (n=10) and the eribulin treatment group (n=9, eribulin, 0.3 mg/kg, i.p., day 1).

Results: On day 8, eribulin significantly inhibited tumor volume compared to the control group (p<0.01). Eribulin regressed tumors in 3 mice (33.3%) and apparently eradicated them in 6 mice (66.7%). At day 14, tumor regrowth was observed in 2 mice of the eribulin group, which was undetectable on day 8. However, 44.4% (4 out of 9) of the mice in the eribulin group were tumor-free on day 14.

Conclusion: A single low-dose eribulin was efficacious on a highly aggressive TNBC. The breast cancer PDOX model can be used to identify highly effective drugs for TNBC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14218DOI Listing
May 2020

Eribulin Regresses a Cisplatinum-resistant Rare-type Triple-negative Matrix-producing Breast Carcinoma Patient-derived Orthotopic Xenograft Mouse Model.

Anticancer Res 2020 May;40(5):2475-2479

AntiCancer Inc, San Diego, CA, U.S.A.

Background/aim: Matrix-producing breast carcinoma (MPBC) is a rare and usually aggressive triple-negative breast cancer (TNBC). In the present report, we determined the drug sensitivity for a triple-negative MPBC using a patient-derived orthotopic xenograft (PDOX) model.

Materials And Methods: The PDOX model was established in the left 2 mammary by surgical orthotopic implantation (SOI). MPBC PDOX models were randomized into 4 groups (6 mice per group) when the tumor volume became 80 mm: G1, control group; G2, cisplatinum group [intraperitoneal (i.p.) injection, weekly, for 2 weeks]; G3, paclitaxel group (i.p., weekly, for 2 weeks); G4, eribulin group [intravenous (i.v.) injection, weekly, for 2 weeks]. All mice were sacrificed on day 15. Tumor volume and body weight were measured one time per week.

Results: The MPBC PDOX model was resistant to cisplatinum (p=0.800). Paclitaxel suppressed tumor growth compared to the control group (p=0.009). However, only eribulin regressed the tumor (p=0.001).

Conclusion: Eribulin has clinical potential for triple-negative MPBC patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/anticanres.14217DOI Listing
May 2020

Oral Recombinant Methioninase Prevents Nonalcoholic Fatty Liver Disease in Mice on a High Fat Diet.

In Vivo 2020 May-Jun;34(3):979-984

AntiCancer Inc, San Diego, CA, U.S.A

Background/aim: We have recently shown that oral recombinant methionase (o-rMETase) prevents obesity and diabetes onset in mice on a high-fat (HF) diet. The present study aimed to determine if o-rMETase can inhibit the onset of nonalcoholic fatty liver disease (NAFLD) onset in mice on a high-fat diet.

Materials And Methods: Male C57BL/6J mice in the control group were fed a normal-fat diet (NFD) (+6.5% fat), and other mice were fed a high-fat (HF) diet (+34.3% fat). Then, the mice on the HF diet were divided into two dietary groups: i) HF+phosphate buffered saline (PBS) group, and ii) HF+o-rMETase group.

Result: The fatty change score in the livers of mice treated with HF+PBS increased to an average of 2.6 during the experimental period of 8 weeks. In contrast, the fatty change in the livers of mice on the HF+o-rMETase group had an average score of 0.92 (p=0.04, HF+PBS vs HF+o-rMETase).

Conclusion: o-rMETase inhibited the onset of NAFLD as well as prevented obesity and the onset of diabetes on a high-fat diet, offering a possibility of a new paradigm to prevent liver cirrhosis or liver cancer via NAFLD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21873/invivo.11866DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7279815PMC
February 2021