NKp44-based chimeric antigen receptor effectively redirects primary T cells against synovial sarcoma.

BACKGROUND: T-cell receptor-engineered T-cell therapies have achieved promising response rates against synovial sarcoma in clinical trials, but their applicability is limited owing to the HLA matching requirement. Chimeric antigen receptor (CAR) can redirect primary T cells to tumor-associated antigens without requiring HLA matching. However, various obstacles, including the paucity of targetable antigens, must be addressed for synovial sarcoma. Ligands for natural killer (NK) cell-activating receptors are highly expressed by tumor cells. METHODS: The surface expression of ligands for NK cell-activating receptors in synovial sarcoma cell lines was analyzed. We analyzed RNA sequencing data deposited in a public database to evaluate NKp44-ligand expression. Primary T cells retrovirally transduced with CAR targeting NKp44 ligands were evaluated for their functions in synovial sarcoma cells. Alterations induced by various stimuli, including a histone deacetylase inhibitor, a hypomethylating agent, inflammatory cytokines, and ionizing radiation, in the expression levels of NKp44 ligands were investigated. RESULTS: Ligands for NKp44 and NKp30 were expressed in all cell lines. NKG2D ligands were barely expressed in a single cell line. None of the cell lines expressed NKp46 ligand. Primary synovial sarcoma cells expressed the mRNA of the truncated isoform of MLL5, a known cellular ligand for NKp44. NKp44-based CAR T cells specifically recognize synovial sarcoma cells, secrete interferon-γ, and exert suppressive effects on tumor cell growth. No stimulus altered the expression of NKp44 ligands. CONCLUSION: NKp44-based CAR T cells can redirect primary human T cells to synovial sarcoma cells. CAR-based cell therapies may be an option for treating synovial sarcomas.

Effectiveness of 4-1BB-costimulated HER2-targeted chimeric antigen receptor T cell therapy for synovial sarcoma.

BACKGROUND: Synovial sarcoma is a rare malignant soft-tissue tumor that is prevalent in adolescents and young adults, and poor prognosis has been reported in patients with metastatic lesions. Chimeric antigen receptor (CAR) T-cell therapy is an emerging novel therapy for solid tumors; however, its application in synovial sarcoma has not yet been explored. METHODS: A novel human epidermal growth factor receptor 2 (HER2)-targeted CAR containing scFv-FRP5, CD8α hinge and transmembrane domains as well as 4-1BB costimulatory and CD3ζ signaling domains was developed. Three synovial sarcoma cell lines that expressed the fusion transcript SS18-SSX1/2/4 were used in the study. Cytokine secretion assay, cytotoxicity assay, and real-time cell analysis experiments were conducted to confirm the function of T cells transduced with the CAR gene. RESULTS: High cell-surface expression of HER2 was observed in all the cell lines. HER2-targeted/4-1BB-costimulated CAR T cells specifically recognized the synovial sarcoma cells, secreted interferon gamma and tumor necrosis factor alpha, and exerted cytotoxic effects in these cells. CONCLUSION: To the best of our knowledge, this is the first study to indicate that HER2-targeted CAR T cells are directly effective against molecularly defined synovial sarcoma cells. Furthermore, our findings might set the basis for developing improved CAR T cell-based therapies for chemo-refractory or relapsed synovial sarcoma.

Development and characterisation of NKp44-based chimeric antigen receptors that confer T cells with NK cell-like specificity.

OBJECTIVES: One of the reasons as to why chimeric antigen receptors (CAR)-T cell therapy for malignancies other than CD19- or BCMA-positive tumors has yet to produce remarkable progress is the paucity of targetable antigens. NKp44 is only expressed by activated natural killer cells and detects a variety of transformed cells, while it reportedly does not react with normal tissues. The aim of this study is to develop CAR-T cell that can target multiple types of tumor cells. METHODS: We created a series of novel CAR constructs in first-generation (1G) and second-generation (2G) CAR format with the extracellular immunoglobulin-like domain of NKp44 (NKp44-CAR). RESULTS: Transduction of the best 1G construct into human primary T cells led to specific cytotoxic effects and cytokine secretion upon encountering multiple types of neoplastic cells including AML, T-ALL and childhood solid tumors. Replacement of the extracellular hinge domain of NKp44 with that of CD8α resulted in diminished CAR function. The 1G NKp44-CAR-T cells exhibited significantly better tumor control in long-term co-culture assays compared with activated NK cells, as well as with NK cells transduced with identical NKp44-CAR. T cells transduced with the best 2G-CAR construct with 4-1BB co-stimulatory domain proliferated at significantly higher levels upon single antigen exposure and showed significantly better tumor control compared with the 1G-CAR and 2G-CAR with CD28 co-stimulatory domain. CONCLUSIONS: NKp44-based CAR endows T cells with NK cell-like anti-tumor specificity. The CAR gene created in this study will be useful for the development of novel gene-modified T-cell immunotherapy.

Determination of copper nanoparticle size distributions with total reflection X-ray fluorescence spectroscopy.

Total reflection X-ray fluorescence (TXRF) analysis is extensively used by the semiconductor industry for measuring trace metal contamination on silicon surfaces. In addition to determining the quantity of impurities on a surface, TXRF can reveal information about the vertical distribution of contaminants by measuring the fluorescence signal as a function of the angle of incidence. In this study, two samples were intentionally contaminated with copper in non-deoxygenated and deoxygenated ultrapure water (UPW) resulting in impurity profiles that were either atomically dispersed in a thin film or particle-like, respectively. The concentration profile of the samples immersed into deoxygenated UPW was calculated using a theoretical concentration profile representative of particles, yielding a mean particle height of 16.1 nm. However, the resulting theoretical profile suggested that a distribution of particle heights exists on the surface. The fit of the angular distribution data was further refined by minimizing the residual error of a least-squares fit employing a model with a Gaussian distribution of particle heights about the mean height. The presence of a height distribution was also confirmed with atomic force microscopy measurements.

Prospective feasibility study to evaluate neoadjuvant-synchronous S-1 + RT for locally advanced rectal cancer: a multicenter phase II trial (UMIN ID: 03396).

In Western countries, the standard treatment for locally advanced rectal cancer is preoperative chemoradiotherapy followed by total mesorectal excision. However, in Japan, the treatment results without preoperative chemoradiotherapy are by no means inferior; therefore, extrapolation of the results of preoperative treatment in Western countries to Japan is controversial. We consider that survival may be improved by preoperative chemoradiotherapy with new anticancer agents as they are expected not only to decrease the local recurrence rate but also to prevent distant metastases. We are conducting a multicentre Phase II study to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy using S-1 in patients with locally advanced rectal cancer. The primary endpoint is the rate of complete treatment of neoadjuvant chemoradiotherapy. Secondary endpoints are the response rate of neoadjuvant chemoradiotherapy, short-term clinical outcomes, rate of curative resection and pathological evaluation. The short-term clinical outcomes are adverse events of neoadjuvant chemoradiotherapy and surgery-related complications. Thirty-five patients are required for this study.

[Complete response in a patient with liver metastasis of esophageal squamous cell carcinoma treated with docetaxel].

On routine endoscopy a Type 2 tumor was found in the esophagogastric junction of a 74-year-old man. A histological diagnosis of squamous cell carcinoma was made based on a biopsy specimen, and lower esophagectomy and proximal gastrectomy were performed. The pathological diagnosis was pT3, N2, M0, pStage III. A low-dose FP treatment as adjuvant chemotherapy was given for only three weeks due to severe anorexia. A liver metastases measuring 22×24 mm in diameter at the s6 lesion was found with a CT examination a year and a half after the operation. A dose of 70 mg/m2 of docetaxel was given by intervenous infusion, and repeated every four weeks. Toxicities, grade 4 neutropenia and mild pneumonia associated with this chemotherapy regimen, were observed after five cycles. Therefore this treatment was discontinued. CT performed at that time showed a complete response (CR) and no more recurrences for six months. Docetaxel treatment is considered to be safe for outpatients and is one of the cures for metastatic esophageal cancer.

Effects of preoperative oral carbohydrates and trace elements on perioperative nutritional status in elective surgery patients.

PURPOSE: In order to enhance postoperative recovery, preoperative consumption of carbohydrate (CHO) drinks has been used to suppress metabolic fluctuations. Trace elements such as zinc and copper are known to play an important role in postoperative recovery. Here, we examined the effects of preoperatively consuming a CHO drink containing zinc and copper. METHODS: Subjects were 122 elective surgery patients divided into two groups (overnight fasting and CHO groups); each group was further divided into morning or afternoon surgery groups. Subjects in the CHO group consumed 300 mL of a CHO drink the night before surgery, followed by 200 ml before morning surgery or 700 ml before afternoon surgery (> or =2 hours before anesthesia induction). Blood levels of glucose, nonesterified fatty acids (NEFA), retinol-binding protein, zinc, and copper were determined. RESULTS: One subject in the CHO group was excluded after refusing the drink. There were no adverse effects from the CHO drink. NEFA levels increased in the fasting groups. Although zinc levels increased in the CHO group immediately after anesthesia induction, no group differences were observed the day after surgery. CONCLUSION: Preoperative consumption of a CHO drink containing trace elements suppressed preoperative metabolic fluctuations without complications and prevented trace element deficiency. Further beneficial effects during the perioperative period can be expected by adding trace elements to CHO supplements.

[A case of advanced gastric cancer treated with S-1/CDDP combination chemotherapy through jejunostomy].

Recently, although chemotherapy for advanced gastric cancer has been proving more highly effective, no standard chemotherapy for gastric cancer has been established. We administered S-1 combined with cisplatin (div) to a patient with advanced gastric cancer who underwent a jejunostomy because of swallowing difficulties (PS 4) due to cerebral infarction. The overall response of this chemotherapy was a partial response (PR) for 14 months. We concluded that the administration of S-1 combined with cisplatin (div) through a jejunostomy can improve the nutrition management and the quality of life (QOL) of a patient with advanced gastric cancer who is incapable of oral intake.

Biotin-rich intranuclear inclusions in morule-lacking adenocarcinoma of the gallbladder: a new category of "neoplastic/non-morular" lesions.

Biotin-rich intranuclear inclusions, also called "optically clear nuclei," are observed in various neoplastic and non-neoplastic lesions, including pregnancy-related endometrium and benign and malignant neoplasms with morular structures. A recent study reported that lesions with biotin-rich intranuclear inclusions can be classified as "(non-neoplastic) pregnancy-related endometrial" and as "(neoplastic) morular" category. In the present report, we describe two cases of well-differentiated adenocarcinoma of the gallbladder in which biotin-rich intranuclear inclusions were found without morular structures. Immunohistochemically, as reported previously, the intranuclear inclusions were positive for biotin and two biotin-binding enzymes (pyruvic acid carboxylase and propionyl CoA carboxylase). Intranuclear expression of beta-catenin was also observed in neoplastic cells with and without intranuclear inclusion. We also detected a frame shift mutation of APC gene in one case but no mutation of beta-catenin gene in both cases. Although intranuclear expression of beta-catenin by mutation of APC gene might contribute to carcinogenesis in our cases, the relationships among intranuclear expressions of beta-catenin, biotin, biotin-binding enzymes and intranuclear inclusions remain unclear. Our cases are the first neoplastic lesions with biotin-rich intranuclear inclusions that lacked morular structures. We propose a new "neoplastic/non-morular" category for lesions with biotin-rich intranuclear inclusions.