Efficacy of tumor-targeting Salmonella typhimurium A1-R on nude mouse models of metastatic and disseminated human ovarian cancer

We report here the efficacy of tumor-targeting Salmonella typhimurium A1-R (A1-R) on mouse models of disseminated and metastatic ovarian cancer. The proliferation-inhibitory efficacy of A1-R on human ovarian cancer cell lines (SKOV-3-GFP, OVCAR-3-RFP) was initially demonstrated in vitro. Orthotopic and dissemination mouse models of ovarian cancer were made with the human ovarian cancer cell line SKOV-3-GFP. After tumor implantation, the mice were treated with A1-R (5 × 10(7)  colony-forming units [CFU], i.v.), and there were no severe adverse events observed. In the orthotopic model, tumor volume after treatment was 276 ± 60.8 mm(3), compared to 930 ± 342 mm(3) in the untreated control group (P = 0.022). There was also a significant difference in survival between treated mice and untreated mice in a peritoneal dissemination model (P = 0.005). The results of this report demonstrate that A1-R is effective for highly aggressive human ovarian cancer in metastatic and dissemination mouse models and suggest its clinical potential for this highly treatment-resistant disease.

Efficacy of tumor-targeting Salmonella typhimurium A1-R in combination with anti-angiogenesis therapy on a pancreatic cancer patient-derived orthotopic xenograft (PDOX) and cell line mouse models

The aim of the present study was to examine the efficacy of tumor-targeting Salmonella typhimurium A1-R treatment following anti-vascular endothelial growth factor (VEGF) therapy on VEGF-positive human pancreatic cancer. A pancreatic cancer patient-derived orthotopic xenograft (PDOX) that was VEGF-positive and an orthotopic VEGF-positive human pancreatic cancer cell line (MiaPaCa-2-GFP) as well as a VEGF-negative cell line (Panc-1) were tested. Nude mice with these tumors were treated with gemcitabine (GEM), bevacizumab (BEV), and S. typhimurium A1-R. BEV/GEM followed by S. typhimurium A1-R significantly reduced tumor weight compared to BEV/GEM treatment alone in the PDOX and MiaPaCa-2 models. Neither treatment was as effective in the VEGF-negative model as in the VEGF-positive models. These results demonstrate that S. typhimurium A1-R following anti-angiogenic therapy is effective on pancreatic cancer including the PDOX model, suggesting its clinical potential.

Precise navigation surgery of tumours in the lung in mouse models enabled by in situ fluorescence labelling with a killer-reporter adenovirus

Background

Current methods of image-guided surgery of tumours of the lung mostly rely on CT. A sensitive procedure of selective tumour fluorescence labelling would allow simple and high-resolution visualisation of the tumour for precise surgical navigation.

Methods

Human lung cancer cell lines H460 and A549 were genetically transformed to express red fluorescent protein (RFP). Tumours were grown subcutaneously for each cell line and harvested and minced for surgical orthotopic implantation on the left lung of nude mice. Tumour growth was measured by fluorescence imaging. After the tumours reached 5 mm in diameter, they were injected under fluorescence guidance with the telomerase-dependent green fluorescent protein (GFP)-containing adenovirus, OBP-401. Viral labelling of the lung tumours with GFP precisely colocalised with tumour RFP expression. Three days after administration of OBP-401, fluorescence-guided surgery (FGS) was performed.

Results

FGS of tumours in the lung was enabled by labelling with a telomerase-dependent adenovirus containing the GFP gene. Tumours in the lung were selectively and brightly labelled. FGS enabled complete lung tumour resection with no residual fluorescent tumour.

Conclusions

FGS of tumours in the lung is feasible and more effective than bright-light surgery.

Tumor-targeting Salmonella typhimurium A1-R decoys quiescent cancer cells to cycle as visualized by FUCCI imaging and become sensitive to chemotherapy

Quiescent cancer cells are resistant to cytotoxic agents which target only proliferating cancer cells. Time-lapse imaging demonstrated that tumor-targeting Salmonella typhimurium A1-R (A1-R) decoyed cancer cells in monolayer culture and in tumor spheres to cycle from G0/G1 to S/G2/M, as demonstrated by fluorescence ubiquitination-based cell cycle indicator (FUCCI) imaging. A1-R infection of FUCCI-expressing subcutaneous tumors growing in nude mice also decoyed quiescent cancer cells, which were the majority of the cells in the tumors, to cycle from G0/G1 to S/G2/M, thereby making them sensitive to cytotoxic agents. The combination of A1-R and cisplatinum or paclitaxel reduced tumor size compared with A1-R monotherapy or cisplatinum or paclitaxel alone. The results of this study demonstrate that A1-R can decoy quiescent cancer cells to cycle to S/G2/M and sensitize them to cytotoxic chemotherapy. These results suggest a new paradigm of bacterial-decoy chemotherapy of cancer.

Tumor-Targeting Salmonella typhimurium A1-R Arrests a Chemo-Resistant Patient Soft-Tissue Sarcoma in Nude Mice

A patient-derived nude-mouse model of soft-tissue sarcoma has been established and treated in the following groups: (1) untreated controls; (2) gemcitabine (GEM) (80 mg/kg, ip, weekly, 3 weeks); (3) Pazopanib (100 mg/kg, orally, daily, 3 weeks) and (4) Salmonella typhimurium A1-R (5 × 10⁷ CFU/body, ip, weekly, 3 weeks). The sarcoma was resistant to GEM (p = 0.879). Pazopanib tended to reduce the tumor volume compared to the untreated mice, but there was no significant difference (p = 0.115). S. typhimurium A1-R significantly inhibited tumor growth compared to the untreated mice (p = 0.001). S. typhimurium A1-R was the only effective treatment for the soft-tissue sarcoma nude mouse model among all treatments including a newly approved multiple tyrosine kinase inhibitor; Pazopanib. These results suggest tumor-targeting S. typhimurium A1-R is a promising treatment for chemo-resistant soft-tissue sarcoma.

Abstract 3241: Tumor-targeting Salmonella typhimurium A1-R inhibits peritoneal dissemination of ovarian cancer and prolongs survival of the tumor-bearing nude mice

Peritoneal dissemination of cancer arising from an intra-abdominal organ has poor prognosis and is treatment resistant. A peritoneal dissemination nude mouse model of ovarian cancer was made with the human ovarian cancer cell line SKOV-3-GFP. Tumor-targeting Salmonella typhimurium A1-R (A1-R) was administrated i.v. or i.p. to the tumor-bearing nude mice. Survival of the tumor-bearing nude mice was prolonged by i.v. administration of A1-R (p = 0.025) as well as by i.p. administration of A1-R (p = 0.00003), compared with the untreated control. There was no significant difference in survival between i.v. and i.p. administration (p = 0.22). However, i.p. administration was less toxic. The present results suggest A1-R has clinical potential for what is currently a highly-treatment-resistant disease.

Citation Format: Yasunori Matsumoto, Shinji Miwa, Ming Zhao, Yong Zhang, Shuya Yano, Fuminari Uehara, Mako Yamamoto, Yukihiko Hiroshima, Makoto Toneri, Michael Bouvet, Hisahiro Matsubara, Robert Hoffmann. Tumor-targeting Salmonella typhimurium A1-R inhibits peritoneal dissemination of ovarian cancer and prolongs survival of the tumor-bearing nude mice. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3241. doi:10.1158/1538-7445.AM2015-3241

Abstract 5338: Preclinical study of telomerase-specific p53 tumor suppressor gene overexpression in human scirrhous gastric cancer cells with different p53 status

Background: Despite multimodal therapy for scirrhous gastric cancer, many patients show refractory to conventional therapy and rapid progression, leading to poor prognosis. Therefore, the development of novel therapeutic strategy is required to improve the clinical outcome in patients with scirrhous gastric cancers. As novel therapeutic strategies, Ad-p53, a replication-defective adenovirus expressing a tumor suppressor p53 gene, is currently under clinical evaluation for various types of cancers. We recently developed a novel p53-expressing telomerase-specific replication-competent oncolytic adenovirus OBP-702, which induces the p53 gene expression in a telomerase-dependent manner. In this study, we investigated the antitumor effects of Ad-p53 and OBP-702 in human scirrhous gastric cancer cells with different p53 status.

Methods: We used 3 human scirrhous gastric cancer cell lines with different p53 status, NUGC4 (p53 wild-type), GCIY (p53 mutant-type), and KATOIII (p53 null). The antitumor effects of Ad-p53 and OBP-702 were evaluated using XTT assay. The 50% inhibiting dose (ID50) value of Ad-p53 and OBP-702 for each cell was calculated using cell viability data obtained 3 days after virus infection. We evaluated the virus-mediated cell death in the sphere-forming cells by LIVE/DEAD assay. The apoptosis- and autophagy-related cell death was assessed by western blot analysis for cleaved poly (ADP-ribose) polymerase (PARP) and p62.

Results: Ad-p53 suppressed the cell viability in p53-inactivated scirrhous gastric cancer cells (KATO III, GCIY), whereas p53-intact NUGC4 cells were resistant to Ad-p53. OBP-702 efficiently suppressed the cell viability in all scirrhous gastric cancer cells with different p53 function. The ID50 value of OBP-702 was lower than that of Ad-p53 in all cell lines. LIVE/DEAD assay showed that OBP-702 induced cell death more efficiently than Ad-p53 in the sphere-forming cells. OBP-702 induced more profound p53 expression and apoptotic cell death than Ad-p53. Moreover, only OBP-702 induced not only apoptosis but also autophagy.

Conclusions: These results suggest that p53-expressing tumor-specific oncolytic adenovirus OBP-702 is a promising antitumor agent to induce profound cell death in scirrhous gastric cancers with different p53 status. Now, in vivo experiments are under way to investigate the antitumor effect of OBP-702 in the peritoneal dissemination of scirrhous gastric cancer cells.

Citation Format: Naoto Hori, Hiroshi Tazawa, Masahiko Nishizaki, Satoru Kikuchi, Shuya Yano, Michihiro Ishida, Megumi Watanabe, Yasuo Urata, Shunsuke Kagawa, Toshiyoshi Fujiwara. Preclinical study of telomerase-specific p53 tumor suppressor gene overexpression in human scirrhous gastric cancer cells with different p53 status. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5338. doi:10.1158/1538-7445.AM2015-5338

Abstract 5123: Curative fluorescence-guided surgery of pancreatic cancer in combination with UVC irradiation in orthotopic mouse models

Fluorescence-guided surgery (FGS) has shown great promise, but has not been shown to be curative. Human MiaPaCa-2 pancreatic cancer cells, expressing green fluorescent protein (GFP), were implanted orthotopically in nude mice. Brightlight surgery (BLS) was performed on 24 tumor-bearing mice. After BLS, mice were randomized to BLS-only (n = 8) or FGS (n = 8) or FGS-UVC (n = 8) groups. The residual tumors were resected using a portable imaging system. FGS or FGS followed by UVC irradiation with 2700 J/m2 UVC (254 nm) was performed. Residual tumor area after FGS was significantly smaller than after BLS only (p = 0.007). The BLS treated mice had reduced survival compared to FGS- and FGS-UVC-treated mice for both relapse-free survival (RFS) (p,0.001 and p,0.001, respectively) and overall survival (OS) (p,0.001 and p,0.001, respectively). With FGS-UVC, RFS lasted at least 150 days indicating the animals were cured. UVC irradiation in combination with FGS has curative potential in the clinic.

Citation Format: Yukihiko Hiroshima, Ali Maawy, Yong Zhang, Sho Sato, Takashi Murakami, Mako Yamamoto, Fuminari Uehara, Shinji Miwa, Shuya Yano, Masashi Momiyama, Takashi Chishima, Kuniya Tanaka, Michael Bouvet, Itaru Endo, Robert M. Hoffman. Curative fluorescence-guided surgery of pancreatic cancer in combination with UVC irradiation in orthotopic mouse models. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5123. doi:10.1158/1538-7445.AM2015-5123

Color-coding cancer and stromal cells with genetic reporters in a patient-derived orthotopic xenograft (PDOX) model of pancreatic cancer enhances fluorescence-guided surgery

Precise fluorescence-guided surgery (FGS) for pancreatic cancer has the potential to greatly improve the outcome in this recalcitrant disease. To achieve this goal, we have used genetic reporters to color code cancer and stroma cells in a patient-derived orthotopic xenograft (PDOX) model. The telomerase-dependent green fluorescent protein (GFP)-containing adenovirus OBP-401 was used to label the cancer cells of a pancreatic cancer PDOX. The PDOX was previously grown in a red fluorescent protein (RFP) transgenic mouse that stably labeled the PDOX stroma cells bright red. The color-coded PDOX model enabled FGS to completely resect the pancreatic tumors including stroma. Dual-colored FGS significantly prevented local recurrence, which bright-light surgery or single-color FGS could not. FGS, with color-coded cancer and stroma cells has important potential for improving the outcome of recalcitrant-cancer surgery.

Selective methioninase-induced trap of cancer cells in S/G2 phase visualized by FUCCI imaging confers chemosensitivity

A major impediment to the response of tumors to chemotherapy is that the large majority of cancer cells within a tumor are quiescent in G₀/G₁, where cancer cells are resistant to chemotherapy. To attempt to solve this problem of quiescent cells in a tumor, cancer cells were treated with recombinant methioninase (rMETase), which selectively traps cancer cells in S/G₂. The cell cycle phase of the cancer cells was visualized with the fluorescence ubiquitination cell cycle indicator (FUCCI). At the time of rMETase-induced S/G₂-phase blockage, identified by the cancer cells' green fluorescence by FUCCI imaging, the cancer cells were administered S/G₂-dependent chemotherapy drugs, which interact with DNA or block DNA synthesis such as doxorubicin, cisplatin, or 5-fluorouracil. Treatment of cancer cells with drugs only, without rMETase-induced S/G₂ phase blockage, led to the majority of the cancer-cell population being blocked in G₀/G₁ phase, identified by the cancer cells becoming red fluorescent in the FUCCI system. The G₀/G₁ blocked cells were resistant to the chemotherapy. In contrast, trapping of cancer cells in S/G₂ phase by rMETase treatment followed by FUCCI-imaging-guided chemotherapy was highly effective in killing the cancer cells.

Tumor-Targeting Salmonella typhimurium A1-R in Combination with Trastuzumab Eradicates HER-2-Positive Cervical Cancer Cells in Patient-Derived Mouse Models

We have previously developed mouse models of HER-2-positive cervical cancer. Tumors in nude mice had histological structures similar to the original tumor and were stained by anti-HER-2 antibody in the same pattern as the patient’s cancer. We have also previously developed tumor-targeting Salmonella typhimurium A1-R and have demonstrated its efficacy against patient-derived tumor mouse models, both alone and in combination. In the current study, we determined the efficacy of S. typhimurium A1-R in combination with trastuzumab on a patient-cancer nude-mouse model of HER-2 positive cervical cancer. Mice were randomized to 5 groups and treated as follows: (1) no treatment; (2) carboplatinum (30 mg/kg, ip, weekly, 5 weeks); (3) trastuzumab (20 mg/kg, ip, weekly, 5 weeks); (4) S. typhimurium A1-R (5 × 10⁷ CFU/body, ip, weekly, 5 weeks); (5) S. typhimurium A1-R (5 × 10⁷ CFU/body, ip, weekly, 5 weeks) + trastuzumab (20 mg/kg, ip, weekly, 5 weeks). All regimens had significant efficacy compared to the untreated mice. The relative tumor volume of S. typhimurium A1-R + trastuzumab-treated mice was smaller compared to trastuzumab alone (p = 0.007) and S. typhimurium A1-R alone (p = 0.039). No significant body weight loss was found compared to the no treatment group except for carboplatinum-treated mice (p = 0.021). Upon histological examination, viable tumor cells were not detected, and replaced by stromal cells in the tumors treated with S. typhimurium A1-R + trastuzumab. The results of the present study suggest that S. typhimurium A1-R and trastuzumab in combination are highly effective against HER-2-expressing cervical cancer.

Targeting tumors with a killer-reporter adenovirus for curative fluorescence-guided surgery of soft-tissue sarcoma

Fluorescence-guided surgery (FGS) of cancer is an area of intense interest. However, FGS of cancer has not yet been shown to be curative due to residual microscopic disease. Human fibrosarcoma HT1080 expressing red fluorescent protein (RFP) was implanted orthotopically in the quadriceps femoris muscle of nude mice. The tumor-bearing mice were injected with high and low-dose telomerase-dependent, green fluorescent protein (GFP)-containing adenovirus OBP-401, which labeled the tumor with GFP. Fluorescence-guided surgery (FGS) or bright light surgery (BLS) was then performed. OBP-401 could label soft-tissue sarcoma (STS) with GFP in situ, concordant with RFP. OBP-401-based FGS resulted in superior resection of STS in the orthotopic model of soft-tissue sarcoma, compared to BLS. High-dose administration of OBP-401 enabled FGS without residual sarcoma cells or local or metastatic recurrence, due to its dual effect of cancer-cell labeling with GFP and killing. High-dose OBP-401 based-FGS improved disease free survival (p = 0.00049) as well as preserved muscle function compared with BLS. High-dose OBP-401-based FGS could cure STS, a presently incurable disease. Since the parent virus of OBP-401, OBP-301, has been previously proven safe in a Phase I clinical trial, it is expected the OBP-401-FGS technology described in the present report should be translatable to the clinic in the near future.

Measurement of pion, kaon and proton production in proton-proton collisions at [Formula: see text] TeV

The measurement of primary [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] production at mid-rapidity ([Formula: see text] 0.5) in proton-proton collisions at [Formula: see text][Formula: see text] 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/[Formula: see text] for pions, from 0.2 up to 6 GeV/[Formula: see text] for kaons and from 0.3 up to 6 GeV/[Formula: see text] for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

3-dimensional tissue is formed from cancer cells in vitro on Gelfoam®, but not on Matrigel™

Cell and tissue culture can be performed on different substrates such as on plastic, in Matrigel™, and on Gelfoam(®), a sponge matrix. Each of these substrates consists of a very different surface, ranging from hard and inflexible, a gel, and a sponge-matrix, respectively. Folkman and Moscona found that cell shape was tightly coupled to DNA synthesis and cell growth. Therefore, the flexibility of a substrate is important for cells to maintain their optimal shape. Human osteosarcoma cells, stably expressing a fusion protein of α(v) integrin and green fluorescent protein (GFP), grew as a simple monolayer without any structure formation on the surface of a plastic dish. When the osteosarcoma cells were cultured within Matrigel™, the cancer cells formed colonies but no other structures. When the cancer cells were seeded on Gelfoam(®), the cells formed three-dimensional tissue-like structures. The behavior of 143B osteosarcoma cells on Gelfoam(®) in culture is remarkably different from those of these cells in monolayer culture or in Matrigel™. Tissue-like structures were observed only in Gelfoam(®) culture. The data in this report suggest a flexible structural substrate such as Gelfoam(®) provides a more in vivo-like culture condition than monolayer culture or Matrigel(TM) and that Matrigel(TM) does not result in actual three-dimensional culture.

Establishment of a patient-derived orthotopic Xenograft (PDOX) model of HER-2-positive cervical cancer expressing the clinical metastatic pattern

Squamous cell carcinoma of the cervix, highly prevalent in the developing world, is often metastatic and treatment resistant with no standard treatment protocol. Our laboratory pioneered the patient-derived orthotopic xenograft (PDOX) nude mouse model with the technique of surgical orthotopic implantation (SOI). Unlike subcutaneous transplant patient-derived xenograft (PDX) models, PDOX models metastasize. Most importantly, the metastasis pattern correlates to the patient. In the present report, we describe the development of a PDOX model of HER-2-positive cervical cancer. Metastasis after SOI in nude mice included peritoneal dissemination, liver metastasis, lung metastasis as well as lymph node metastasis reflecting the metastatic pattern in the donor patient. Metastasis was detected in 4 of 6 nude mice with primary tumors. Primary tumors and metastases in the nude mice had histological structures similar to the original tumor and were stained by an anti-HER-2 antibody in the same pattern as the patient's cancer. The metastatic pattern, histology and HER-2 tumor expression of the patient were thus preserved in the PDOX model. In contrast, subcutaneous transplantation of the patient's cervical tumors resulted in primary growth but not metastasis.

Patient-derived orthotopic xenograft (PDOX) nude mouse model of soft-tissue sarcoma more closely mimics the patient behavior in contrast to the subcutaneous ectopic model

AIM

Soft-tissue sarcomas are a group of rare mesenchymal carcinomas that include approximately 50 histological types, and account for 1% of all adult cancer cases. The yearly incidence of soft-tissue sarcomas in the USA is approximately 11,280 cases, with an overall mortality of 3,900 deaths per year.

MATERIALS AND METHODS

In this study, we established a patient-derived orthotopic xenograft (PDOX) from a patient with a soft-tissue sarcoma of the retroperitoneum in nude mice and compared it to a subcutaneous patient-derived model of the same tumor for histology.

RESULTS

In the PDOX model, a bulky tumor grew in the left retroperitoneum in the same manner as the patient's tumor. Upon histological examination, the majority of the PDOX tissue section comprised sarcomatous high-grade spindle cells of varying sizes, similar to the original patient tumor. In contrast, the majority of the subcutaneously-implanted tumor comprised round to oval cells.

CONCLUSION

These results indicate that the PDOX recapitulated the histology of the original tumor more than the subcutaneous model.

Production of [Formula: see text] and [Formula: see text] in proton-proton collisions at [Formula: see text] 7 TeV

The production of the strange and double-strange baryon resonances ([Formula: see text], [Formula: see text]) has been measured at mid-rapidity ([Formula: see text][Formula: see text]) in proton-proton collisions at [Formula: see text] [Formula: see text] 7 TeV with the ALICE detector at the LHC. Transverse momentum spectra for inelastic collisions are compared to QCD-inspired models, which in general underpredict the data. A search for the [Formula: see text] pentaquark, decaying in the [Formula: see text] channel, has been carried out but no evidence is seen.

Exclusive J/ψ photoproduction off protons in ultraperipheral p-Pb collisions at √(s(NN))=5.02 TeV

We present the first measurement at the LHC of exclusive J/ψ photoproduction off protons, in ultraperipheral proton-lead collisions at sqrt[s_{NN}]=5.02  TeV. Events are selected with a dimuon pair produced either in the rapidity interval, in the laboratory frame, 2.5<y<4 (p-Pb) or -3.6<y<-2.6 (Pb-p), and no other particles observed in the ALICE acceptance. The measured cross sections σ(γ+p→J/ψ+p) are 33.2±2.2(stat)±3.2(syst)±0.7(theor)  nb in p-Pb and 284±36(stat)_{-32}^{+27}(syst)±26(theor)  nb in Pb-p collisions. We measure this process up to about 700 GeV in the γp center of mass, which is a factor of two larger than the highest energy studied at HERA. The data are consistent with a power law dependence of the J/ψ photoproduction cross section in γp energies from about 20 to 700 GeV, or equivalently, from Bjorken x scaling variable between ∼2×10^{-2} and ∼2×10^{-5}, thus indicating no significant change in the gluon density behavior of the proton between HERA and LHC energies.