A materials informatics driven fine-tuning of triazine-based electron-transport layer for organic light-emitting devices

Materials informatics in the development of organic light-emitting diode (OLED) related materials have been performed and exhibited the effectiveness for finding promising compounds with a desired property. However, the molecular structure optimization of the promising compounds through the conventional approach, namely the fine-tuning of molecules, still involves a significant amount of trial and error. This is because it is challenging to endow a single molecule with all the properties required for practical applications. The present work focused on fine-tuning triazine-based electron-transport materials using machine learning (ML) techniques. The prediction models based on localized datasets containing only triazine derivatives showed high prediction accuracy. The descriptors from density functional theory calculations enhanced the prediction of the glass transition temperature. The proposed multistep virtual screening approach extracted the promising triazine derivatives with the coexistence of higher electron mobility and glass transition temperature. Nine selected triazine compounds from 3,670,000 of the initial search space were synthesized and used as the electron transport layer for practical OLED devices. Their observed properties matched the predicted properties, and they enhanced the current efficiency and lifetime of the device. This paper provides a successful model for the ML assisted fine-tuning that effectively accelerates the development of practical materials.

Oncological and functional outcomes of modified arthroscopic resection for intra-articular tenosynovial giant cell tumor of the knee using multiple portals

BACKGROUND

Arthroscopic resection of tenosynovial giant cell tumor (TS-GCT) presents favorable outcomes. However, there are reportedly higher recurrence rates in patients who had incomplete resection. To minimize incomplete resection, we established a multiple portal approach depending on the location of the disease. In this study, we aimed to retrospectively evaluate the clinical outcomes of arthroscopic resection for both localized and diffuse types of TS-GCT of the knee.

METHODS

From 2009 to 2019, 13 patients who underwent arthroscopic synovectomy of the knee and were histologically diagnosed with TS-GCT were included in this study. The pre- and postoperative range of motion (ROM) of the knee was measured. The Japanese Orthopaedic Association (JOA) score and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were assessed at the final follow-up examination. Magnetic resonance imaging was performed to detect incomplete resection or local recurrence.

RESULTS

Among the 13 patients, seven and six had localized and diffuse type TS-GCT, respectively. Regarding the knee ROM, preoperative knee flexion in patients with the localized type was limited compared with that in those with the diffuse type. However, the ROM was significantly improved in patients with both types postoperatively. The JOA score and KOOS of patients with both types at the final follow-up were favorable, and there were no significant differences between both types. There was neither recurrence nor incomplete resection in any patient for both types.

CONCLUSION

All patients, regardless of the TS-GCT type, achieved favorable outcomes after arthroscopic surgery; especially, the failure rate was 0%.

Management of Rheumatoid Arthritis: Possibilities and Challenges of Mesenchymal Stromal/Stem Cell-Based Therapies

Rheumatoid arthritis (RA) is a highly prevalent, chronic, and progressive autoimmune disorder primarily affecting joints and muscles. The associated inflammation, pain, and motor restriction negatively impact patient quality of life (QOL) and can even contribute to premature mortality. Further, conventional treatments such as antiinflammatory drugs are only symptomatic. Substantial progress has been made on elucidating the etiopathology of overt RA, in particular the contributions of innate and adaptive immune system dysfunction to chronic inflammation. Although the precise mechanisms underlying onset and progression remain elusive, the discovery of new drug targets, early diagnosis, and new targeted treatments have greatly improved the prognosis and QOL of patients with RA. However, a sizable proportion of patients develop severe adverse effects, exhibit poor responses, or cannot tolerate long-term use of these drugs, necessitating more effective and safer therapeutic alternatives. Mounting preclinical and clinical evidence suggests that the transplantation of multipotent adult stem cells such as mesenchymal stromal/stem cells is a safe and effective treatment strategy for controlling chronic inflammation and promoting tissue regeneration in patients with intractable diseases, including RA. This review describes the current status of MSC-based therapies for RA as well as the opportunities and challenges to broader clinical application.

Relationship between the morphology of osteophytes and cartilage lesions in anterior ankle impingement in athletes: a cross-sectional study

BACKGROUND

The present study aimed to describe the frequency and severity of tram-track lesions in anterior ankle impingement in athletes and to evaluate the association between osteophyte morphology and severity of tram-track lesions, the distinctive cartilage lesions associated with tibial osteophytes in anterior ankle impingement syndrome.

METHODS

We evaluated 34 athletes who underwent arthroscopic osteophyte resection for anterior ankle impingement between January 2017 and March 2021.

RESULTS

We found tram-track lesions in 26 athletes (76.5%). Arthroscopic findings revealed the distribution of the International Cartilage Repair Society grades of tram-track lesions (grade 0, eight; grade 1, seven; grade 2, ten; grade 3, nine; grade 4, zero). These findings indicate that athletes with anterior ankle impingement syndrome may have more severe cartilage lesions than non-athletes. There was a positive correlation between the International Cartilage Repair Society grade and osteophyte size (r = 0.393, p = 0.021). We divided athletes into two groups according to the presence or absence of osteophyte protrusion into the joint space. Osteophyte protrusion was present in 14 athletes (41.2%). All athletes in the protrusion-type group had tram-track lesions; seven (50%) had International Cartilage Repair Society grade 3. The protrusion-type group's International Cartilage Repair Society grade was significantly higher than that of the non-protrusion-type group (p = 0.008). The osteophyte sizes in the two groups were not significantly different (p = 0.341).

CONCLUSIONS

Based on these findings, osteophyte protrusion should be assessed when an indication of arthroscopic treatment for anterior ankle impingement syndrome is considered, particularly in athletes.

Masticatory Behavior Change with a Wearable Chewing Counter: A Randomized Controlled Trial

Because a relationship has been reported between masticatory behavior, obesity, and postprandial blood glucose, it is recommended to chew well and take a longer time to eat. The purpose of this study was to examine the possibility of changing masticatory behavior using a small ear-hung wearable chewing counter, which can monitor masticatory behavior without disturbing daily meals. In total, 235 healthy volunteers participated in a 4-wk randomized controlled trial and were divided into 3 groups. All participants were instructed about the importance of mastication at the first visit. During the intervention, group B used the chewing counter without an algorithm during each meal (notification of the number of chews after meal), and group C used the chewing counter with a masticatory behavior change algorithm (setting a target value and displaying the number of chews in real time). Group A was set as the control group. The number of chews and the meal time when consuming 1 rice ball (100 g) were measured before and after the intervention using the chewing counter, and the rate of change in these values was evaluated. Participants also provided a subjective evaluation of their changes in masticatory behavior. The number of chews and the meal time of 1 rice ball increased significantly in groups B and C compared with before the intervention, and the rate of change was significantly higher in group C than in group A and group B. In addition, the subjective evaluation of the change in the number of chews was highest in group C. Self-monitoring of masticatory behavior by providing a target value and the degree of achievement for the number of chews using a wearable chewing counter with a behavioral change algorithm could promote effective change in masticatory behavior and lead to an increased number of chews. (Trial ID: UMIN000034476).

Imaging the interaction of αv integrin-GFP in osteosarcoma cells with RFP-expressing host stromal cells and tumor-scaffold collagen in the primary and metastatic tumor microenvironment

Human osteosarcoma 143B cells were previously stably transfected with an αv integrin green flourescent protein (GFP) vector. 143B cells expressing αv integrin-GFP were transplanted orthotopically in the tibia of transgenic nude mice ubiquitously expressing red fluorescent protein (RFP). The primary tumors acquired RFP-expressing stroma and were passaged orthotopically in the tibia in noncolored nude mice, which maintained the RFP stroma. The interaction of αv integrin-GFP expression in 143B cells with RFP-expressing host stromal cells was observed by confocal microscopy using the Olympus FV1000. Collagen fibers were imaged simultaneously in reflectance mode. The RFP-expressing stroma included cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) which persisted even 3 weeks after passage to nontransgenic nude mice. CAFs expressing RFP were aligned between collagen fibers and cancer cells expressing αv integrin-GFP. Six weeks after transplantation, pulmonary metastases expressing αv integrin-GFP could be identified. TAMs expressing RFP accompanied metastasized osteosarcoma cells expressing αv integrin-GFP in the lung. The current study demonstrates the importance of αv integrin interaction with stromal elements in osteosarcoma.

Tumor-targeting Salmonella typhimurium A1-R Inhibits Osteosarcoma Angiogenesis in the In Vivo Gelfoam® Assay Visualized by Color-coded Imaging

BACKGROUND

We previously developed a color-coded imaging model that can quantify the length of nascent blood vessels using Gelfoam® implanted in nestin-driven green fluorescent protein (ND-GFP) nude mice. In this model, nascent blood vessels selectively express GFP. We also previously showed that osteosarcoma cells promote angiogenesis in this assay. We have also previously demonstrated the tumor-targeting bacteria Salmonella typhimurium A1-R (S. typhimurium A1-R) can inhibit or regress all tested tumor types in mouse models. The aim of the present study was to determine if S. typhimurium A1-R could inhibit osteosarcoma angiogenesis in the in vivo Gelfoam® color-coded imaging assay.

MATERIALS AND METHODS

Gelfoam® was implanted subcutaneously in ND-GFP nude mice. Skin flaps were made 7 days after implantation and 143B-RFP human osteosarcoma cells expressing red fluorescent protein (RFP) were injected into the implanted Gelfoam. After establishment of tumors in the Gelfoam®, control-group mice were treated with phosphate buffered saline via tail-vein injection (iv) and the experimental group was treated with S. typhimurium A1-R iv Skin flaps were made at day 7, 14, 21, and 28 after implantation of the Gelfoam® to allow imaging of vascularization in the Gelfoam® using a variable-magnification small-animal imaging system and confocal fluorescence microscopy.

RESULTS

Nascent blood vessels expressing ND-GFP extended into the Gelfoam® over time in both groups. However, the extent of nascent blood-vessel growth was significantly inhibited by S. typhimurium A1-R treatment by day 28.

CONCLUSION

The present results indicate S. typhimurium A1-R has potential for anti-angiogenic targeted therapy of osteosarcoma.

Use of αv Integrin Linked to Green Fluorescent Protein in Osteosarcoma Cells and Confocal Microscopy to Image Molecular Dynamics During Lung Metastasis in Nude Mice

BACKGROUND

We report here imaging of the behavior of αv integrin linked to green fluorescent protein (GFP) in human osteosarcoma cells colonizing the lung of nude mice.

MATERIALS AND METHODS

143B osteosarcoma cells expressing αv integrin-GFP were generated by transfection of an αv integrin-GFP fusion-gene vector pCMV-AC- ITGAV-GFP. In order to generate experimental lung metastases, 143B osteosarcoma cells (1×10(6)), stably expressing αv integrin-GFP, were injected intravenously via the tail vein. The osteosarcoma cells were transplanted orthotopically in the tibia of nude mice in order to generate spontaneous metastases. Lungs were harvested and imaged by confocal microscopy within 1 hour.

RESULTS

In the experimental lung-metastasis model, extravasating and deformed osteosarcoma cells expressing αv integrin-GFP were observed. Pseudopodia of the osteosarcoma cells contained small puncta of αv integrin-GFP. In early-stage spontaneous lung metastasis, tumor emboli were observed in pulmonary vessels. At high magnification, small αv integrin-GFP puncta were observed in the tumor embolus. In late-stage spontaneous metastasis, tumor emboli were also observed in pulmonary vessels. Invading cancer cells with strong expression of αv integrin-GFP were observed at the margin of the tumor emboli.

CONCLUSION

The results of this study demonstrate that molecular dynamics of αv integrin-GFP can be imaged in lung metastasis, which will allow further understanding of the role of αv integrin in this process. The results also suggest a general concept for imaging molecular behavior in vivo.

Efficacy of the Combination of a PARP Inhibitor and UVC on Cancer Cells as Imaged by Focus Formation by the DNA Repair-related Protein 53BP1 Linked to Green Fluorescent Protein

BACKGROUND

The ability to image DNA repair in cancer cells after irradiation, as well as its inhibition by potential therapeutic agents, is important for the further development of effective cancer therapy. 53BP1 is a DNA repair protein that is overexpressed and forms foci when double-stranded DNA breaks occur in DNA.

MATERIALS AND METHODS

The re-localization of green fluorescent protein (GFP) fused to the chromatin-binding domain of 53BP1 to form foci was imaged after UVC irradiation of breast and pancreatic cancer cells expressing 53BP1-GFP using confocal microscopy.

RESULTS

During live-cell imaging, 53BP1-GFP focus formation was observed within 10 minutes after UVC irradiation. Most 53BP1 foci resolved by 100 minutes. To block UVC-induced double-strand break repair in cancer cells, poly(ADP-ribose) polymerase (PARP) was targeted with ABT-888 (veliparib). PARP inhibition markedly enhanced UVC-irradiation-induced persistence of 53BP1-foci, even beyond 100 minutes after UVC irradiation, and reduced proliferation of breast and pancreatic cancer cells.

CONCLUSION

Confocal microscopy of 53BP1-GFP is a powerful method for imaging UVC-induced DNA damage and repair, as well as inhibition of repair.

Real-time fluorescence imaging of the DNA damage repair response during mitosis

The response to DNA damage during mitosis was visualized using real-time fluorescence imaging of focus formation by the DNA-damage repair (DDR) response protein 53BP1 linked to green fluorescent protein (GFP) (53BP1-GFP) in the MiaPaCa-2(Tet-On) pancreatic cancer cell line. To observe 53BP1-GFP foci during mitosis, MiaPaCa-2(Tet-On) 53BP1-GFP cells were imaged every 30 min by confocal microscopy. Time-lapse imaging demonstrated that 11.4 ± 2.1% of the mitotic MiaPaCa-2(Tet-On) 53BP1-GFP cells had increased focus formation over time. Non-mitotic cells did not have an increase in 53BP1-GFP focus formation over time. Some of the mitotic MiaPaCa-2(Tet-On) 53BP1-GFP cells with focus formation became apoptotic. The results of the present report suggest that DNA strand breaks occur during mitosis and undergo repair, which may cause some of the mitotic cells to enter apoptosis in a phenomenon possibly related to mitotic catastrophe.

Intraperitoneal administration of tumor-targeting Salmonella typhimurium A1-R inhibits disseminated human ovarian cancer and extends survival in nude mice

Peritoneal disseminated cancer is highly treatment resistant. We here report the efficacy of intraperitoneal (i.p.) administration of tumor-targeting Salmonella typhimurium A1-R in a nude mouse model of disseminated human ovarian cancer. The mouse model was established by intraperitoneal injection of the human ovarian cancer cell line SKOV3-GFP. Seven days after implantation, mice were treated with S. typhimurium A1-R via intravenous (i.v.) or i.p. administration at the same dose, 5×10⁷ CFU, once per week. Both i.v. and i.p. treatments effected prolonged survival compared with the untreated control group (P=0.025 and P<0.001, respectively). However, i.p. treatment was less toxic than i.v. treatment. Tumor-specific targeting of S. typhimurium A1-R was confirmed with bacterial culture from tumors and various organs and tumor or organ colony formation after i.v. or i.p. injection. Selective tumor targeting was most effective with i.p. administration. The results of the present study show S. typhimurium A1-R has promising clinical potential for disseminated ovarian cancer, especially via i.p. administration.

Cell-cycle fate-monitoring distinguishes individual chemosensitive and chemoresistant cancer cells in drug-treated heterogeneous populations demonstrated by real-time FUCCI imaging

Essentially every population of cancer cells within a tumor is heterogeneous, especially with regard to chemosensitivity and resistance. In the present study, we utilized the fluorescence ubiquitination-based cell cycle indicator (FUCCI) imaging system to investigate the correlation between cell-cycle behavior and apoptosis after treatment of cancer cells with chemotherapeutic drugs. HeLa cells expressing FUCCI were treated with doxorubicin (DOX) (5 μM) or cisplatinum (CDDP) (5 μM) for 3 h. Cell-cycle progression and apoptosis were monitored by time-lapse FUCCI imaging for 72 h. Time-lapse FUCCI imaging demonstrated that both DOX and CDDP could induce cell cycle arrest in S/G2/M in almost all the cells, but a subpopulation of the cells could escape the block and undergo mitosis. The subpopulation which went through mitosis subsequently underwent apoptosis, while the cells arrested in S/G2/M survived. The present results demonstrate that chemoresistant cells can be readily identified in a heterogeneous population of cancer cells by S/G2/M arrest, which can serve in future studies as a visible target for novel agents that kill cell-cycle-arrested cells.

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.

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 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

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.

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.

Fluorescence-guided surgery improves outcome in an orthotopic osteosarcoma nude-mouse model

In order to develop a model for fluorescence-guided surgery (FGS), 143B human osteosarcoma cells expressing red fluorescent protein (RFP) were injected into the intramedullary cavity of the tibia in nude mice. The fluorescent areas of residual tumors after bright-light surgery (BLS) and FGS were 10.2 ± 2.4 mm(2) and 0.1 ± 0.1 mm(2) , respectively (p<0.001). The BLS-treated mice and BLS+cisplatinum (CDDP)-treated mice had significant recurrence. In contrast, the FGS mice and FGS+CDDP mice had very little recurring tumor growth. Disease-free survival (DFS) in the BLS-, BLS+CDDP-, FGS-, and FGS+CDDP-treated mice was 12.5%, 37.5%, 75.0%, and 87.5%, respectively. The FGS-treated mice had a significantly higher DFS rate than the BLS-treated mice (p=0.021). The FGS+CDDP-treated mice had significantly higher DFS rate than the BLS+CDDP-treated mice (p=0.043). Although chemotherapy significantly reduced multiple metastases (p=0.033), there was no significant correlation between FGS and lung metastasis. FGS significantly reduced the recurrence of the primary tumor but did not reduce lung metastasis. The combination of FGS and adjuvant CDDP reduced tumor recurrence and prevented multiple metastases. FGS and adjuvant chemotherapy should be performed as early as possible in the disease to prevent both recurrence and metastatic development.

Abstract B01: A portable imaging system for fluorescence-guided surgery on a human colon cancer patient-derived orthotopic xenograft (PDOX™) nude mouse model

In this study, we determined the effectiveness of fluorescence-guided surgery (FGS) using a fluorophore-conjugated anti-carcinoembryonic antigen (CEA) antibody on a colon-cancer patient-derived orthotopic xenografts (PDOX™) nude mouse model. The patient tumor was established in NOD/SCID mice and passed orthotopically in nude mice to make PDOX™ models. Eight weeks after orthotopic implantation in nude mice, a monoclonal anti-CEA antibody conjugated with Alexa 488 was delivered to the PDOX™ models as a single intravenous dose 24 hours before laparotomy. The tumor was completely resected under fluorescence guidance using a hand-held portable fluorescence imaging system. Frozen section microscopy of the resected specimen demonstrated that the anti-CEA antibody selectively labeled cancer cells in the colon cancer PDOX™. Histologic evaluation of the resected specimen demonstrated that cancer cells were not present in the margins. The results of the present report predict that FGS using a fluorophore-conjugated anti-CEA antibody and hand-held portable imaging system should improve intraoperative staging and efficacy of resection for colorectal cancer in the clinic.

Citation Format: Yukihiko Hiroshima, Ali Maawy, Sharmeela Kaushal, Yong Zhang, Fuminari Uehara, Shinji Miwa, Shuya Yano, Sho Sato, Takashi Murakami, Masashi Momiyama, Takashi Chishima, Kuniya Tanaka, Michael Bouvet, Itaru Endo, Robert M. Hoffman. A portable imaging system for fluorescence-guided surgery on a human colon cancer patient-derived orthotopic xenograft (PDOX™) nude mouse model. [abstract]. In: Proceedings of the AACR Special Conference: The Translational Impact of Model Organisms in Cancer; Nov 5-8, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2014;12(11 Suppl):Abstract nr B01.

Abstract A40: Pancreatic cancer patient-derived orthotopic xenograft (PDOX™) is effectively targeted by Salmonella typhimurium A1-R

The aim of this study is to determine the efficacy of tumor-targeting Salmonella typhimurium A1-R (A1-R) (Cancer Disc. 2, 588-590, 2012) on pancreatic cancer PDOX™ compared to standard chemotherapy. The PDOX™ was grown in transgenic nude red fluorescent protein (RFP) mice in order that the PDOX™ acquire RFP-expressing stroma in order to label the tumor. The RFP-PDOX™ were then orthotopically transplanted to non-transgenic nude mice in order to image tumor growth and drug efficacy. The RFP labeled stroma are stable upon passage. A1-R treatment significantly reduced tumor weight as well as tumor fluorescence area compared to untreated control (p = 0.011), with comparable efficacy of gemcitabine, cisplatin and 5-FU. A1-R had the highest efficacy compared to any of the chemotherapy drugs tested based on Evan's histological response criteria. The present report demonstrates Salmonella typhimurium A1-R was effective for human pancreatic PDOX™ and is a promising therapy for this highly treatment-resistant disease.

Citation Format: Yukihiko Hiroshima, Ming Zhao, Ali Maawy, Yong Zhang, Matthew H.G. Katz, Jason B. Fleming, Fuminari Uehara, Shinji Miwa, Shuya Yano, Masashi Momiyama, Atsushi Suetsugu, Takashi Chishima, Kuniya Tanaka, Michael Bouvet, Itaru Endo, Robert M. Hoffman. Pancreatic cancer patient-derived orthotopic xenograft (PDOX™) is effectively targeted by Salmonella typhimurium A1-R. [abstract]. In: Proceedings of the AACR Special Conference: The Translational Impact of Model Organisms in Cancer; Nov 5-8, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2014;12(11 Suppl):Abstract nr A40.

Fluorescence-guided surgery of prostate cancer bone metastasis

BACKGROUND

The aim of this study is to investigate the effectiveness of fluorescence-guided surgery (FGS) of prostate cancer experimental skeletal metastasis.

MATERIALS AND METHODS

Green fluorescent protein-expressing PC-3 human prostate cancer cells (PC-3-green fluorescent protein) were injected into the intramedullary cavity of the tibia in 32 nude mice. After 2 wk, 16 of the mice underwent FGS; the other 16 mice underwent bright-light surgery (BLS). Half of BLS and FGS mice (8 mice in each group) received zoledronic acid (ZOL). Weekly fluorescence imaging of the mice was performed. Six weeks after surgery, metastases to lung and inguinal lymph node were evaluated by fluorescence imaging.

RESULTS

The percentage of residual tumor after BLS and FGS was 9.9 ± 2.2% and 0.9 ± 0.3%, respectively (P < 0.001). FGS reduced recurrent cancer growth compared with BLS (P < 0.005). Although FGS alone had no significant effect on inguinal lymph node metastases, lung metastasis or disease-free survival (DFS), ZOL in combination with FGS significantly increased DFS (P = 0.01) in comparison with the combination of BLS and ZOL. ZOL reduced lymph node metastases (P = 0.033) but not lung metastasis.

CONCLUSIONS

FGS significantly reduced recurrence of experimental prostate cancer bone metastasis compared with BLS. The combination of FGS and ZOL increased DFS over BLS and ZOL. ZOL inhibited lymph node metastasis but not lung metastasis.

Abstract 2384: Time-lapse imaging of response to DNA damage occuring during mitosis

The DNA damage response protein 53BP1 forming foci when double-stranded breaks occur in DNA. In this study, the response to DNA damage during mitosis was visualized using fluorescent protein-based real-time imaging of 53BP1 linked to GFP (GFP-53BP1) focus formation by the fusion protein in the MiaPaCa2 Tet-On Advanced cell line. The MiaPaCa2Tet-On GFP-53BP1 cells were cultured in 35 mm dishes for 48 h. 53BP1 foci were observed every 30 minutes with the FluoView FV1000 confocal laser microscope (Olympus Corp., Tokyo, Japan). The increased expression of GFP-53BP1 was observed during mitosis in MiaPaCa2Tet-On GFP-53BP1 cells without any treatment Mitotic changes were observed 1.09 ± 0.10 times in each cell during over 24 h. Apoptotic changes were observed in 7.3 ± 3.3% of the cells during the 24 h. During the time-lapse imaging, focus formation of GFP-53BP1 was observed in 11.4 ± 2.1% of the mitotic cells during over 24 h. Non-mitotic cells did not have an increase in GFP-53BP1 focus formation. This study indicates that DNA strand breaks occur during mitosis and can be repaired, at least to some extent.

Citation Format: Shinji Miwa, Shuya Yano, Mako Yamamoto, Yukihiko Hiroshima, Fuminari Uehara, Yasunori Matsumoto, Hiroaki Kimura, Katsuhiro Hayashi, Elena V. Efimova, Hiroyuki Tsuchiya, Robert M. Hoffman. Time-lapse imaging of response to DNA damage occuring during mitosis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2384. doi:10.1158/1538-7445.AM2014-2384

Abstract 710: The efficacy of tumor-targeting Salmonella typhimurium A1-R on bone metastasis

We have previously developed a genetically-modified bacterial strain of Salmonella typhimurium (A1-R), which expresses GFP. In this study, we measured the efficacy of A1-R on breast cancer bone metastasis. We established an early-stage bone-metastasis model in nude mice by cardiac injection and a late-stage model by injection into the intramedullary cavity of the tibia using MDA-MB-435 human breast cancer cells (Human breast cancer cell lines co-express neuronal, epithelial, and melanocytic differentiation markers in vitro and in vivo. PLoS One 5, e9712, 2010). Both mouse models of bone metastasis were treated with A1-R. Fluorescence imaging of the mice was performed to visualize the metastatic bone lesions. In a first set of experiments, we showed that A1-R invaded and replicated intracellularly in MDA-MB-435-GFP cells in vitro. A1-R dose-dependently inhibited proliferation of MDA-MB-435-GFP cells. In the early-stage bone-metastasis model, A1-R significantly improved metastasis-free survival. In the advanced-stage bone-metastasis model, A1-R significantly inhibited the growth of the metastatic lesions. These data indicated that A1-R is useful to prevent and inhibit the growth of metastatic breast cancer bone tumors.

Citation Format: Shinji Miwa, Ming Zhao, Shuya Yano, Yong Zhang, Fuminari Uehara, Yasunori Matsumoto, Yukihiko Hiroshima, Mako Yamamoto, Hiroaki Kimura, Katsuhiro Hayashi, Hiroyuki Tsuchiya, Robert M. Hoffman. The efficacy of tumor-targeting Salmonella typhimurium A1-R on bone metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 710. doi:10.1158/1538-7445.AM2014-710

Abstract 711: Salmonella typhimurium A1-R induces quiescent FUCCI-expressing cancer cells to cycle and become chemosensitive

Quiescent cancer cells are resistant to cytotoxic agents which target only proliferating cancer cells. Time-lapse imaging showed that Salmonella typhimurium A1-R (A1-R) encircled and invaded quiescent cancer cells in monolayer culture, thereby eliminating them. Moreover A1-R infected and killed quiescent fluorescent ubiquitination-based cell cycle indicator (FUCCI)-expressing cancer cells in tumor spheres. In contrast, cytotoxic agents did not kill quiescent cancer cells in tumor spheres. A1-R infection of FUCCI-expressing subcutaneous tumors growing in nude mice resulted in killing quiescent cancer cells resistant to cytotoxic agents. Furthermore, the combination of A1-R and cisplatin reduced tumor size compared with A1-R monotherapy or cisplatin alone. This study demonstrates that A1-R can kill quiescent cancer cells and also sensitize them to conventional chemotherapy. These results suggest a new therapeutic paradigm potentially more effective than current therapeutics which are ineffective against quiescent cancer cells.

Citation Format: Shuya Yano, Yong Zhang, Ming Zhao, Yukihiko Hiroshima, Shinji Miwa, Fuminari Uehara, Hiroyuki Kishimoto, Hiroshi Tazawa, Toshiyoshi Fujiwara, Robert M. Hoffman. Salmonella typhimurium A1-R induces quiescent FUCCI-expressing cancer cells to cycle and become chemosensitive. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 711. doi:10.1158/1538-7445.AM2014-711

Abstract 3486: Efficacy of neoadjuvant chemotherapy in combination with fluorescence-guided surgery on a pancreatic cancer patient-derived orthotopic xenograft (PDOX)

The aim of this study is to determine the efficacy of neoadjuvant chemotherapy (NAC) in combination with fluorescence-guided surgery (FGS) on pancreatic cancer patient derived orthotopic xenograft (PDOX). We established the PDOX from the patient suffering from metastatic CA19-9-positive pancreatic cancer. Forty nude mice were implanted with tumor using surgical orthotopic implantation (SOI) on the nude mouse pancreas. Four weeks after implantation, the mice with tumor were randomized into 4 treatment groups: (1) bright-light surgery (BLS) only; (2) FGS; (3) NAC-BLS; (4) NAC-FGS. Gemcitabine (80 mg/kg, ip, weekly, 3 weeks) was used for NAC. Seven weeks after implantation, BLS was performed on all tumor-bearing mice. A monoclonal anti-human CA19-9 antibody conjugated with Dylight 650 was delivered to tumor-bearing mice in the FGS groups as a single intravenous dose 24 hours before BLS. Postoperatively, the surgical resection bed of FGS mice were imaged with the OV100 fluorescence imaging system to detect fluorescent residual tumors. The fluorescent residual tumors of FGS groups were then resected under fluorescence navigation. The average resected tumor weight of each group was as follows: (1) BLS, 188.5 ± 50.0 mg; (2) FGS, 278.0 ± 111.4 mg; (3) NAC-BLS, 84.5 ± 48.7 mg; (4) NAC-FGS, 141.8 ± 48.9 mg. The average resected tumor weight of NAC groups was significantly less than the non-NAC groups (113.1 ± 57.0 mg and 235.6 ± 94.3 mg, respectively; p&gt;0.001). The average resected tumor weight of the FGS groups was significantly larger than the BLS groups (213.4 ± 107.1 mg and 136.5 ± 73.8 mg, respectively; p=0.016). Eight weeks after resection, we performed laparotomy to examine recurrence. The recurrence rate of each group was as follows: (1) BLS, 9 / 9 (100%); (2) FGS, 4 / 8 (50%); (3) NAC-BLS, 6 / 9 (66.7%); (4) NAC-FGS, 2 / 8 (25%). The recurrence rate of FGS groups was significantly lower than BLS groups (6 /16; 37.5% and 15 / 18; 83.3%, respectively; p=0.012), whereas there was no significant difference between FGS and NAC-FGS groups (p=0.608). There was no significant difference in the total recurrence rate between NAC and non-NAC groups (p=0.157). However NAC significantly reduced peritoneal recurrence (29.4 % and 0%, respectively; p=0.044). The results indicate that NAC in combination with FGS might reduce or even eliminate the peritoneal recurrence of pancreatic cancer.

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. Efficacy of neoadjuvant chemotherapy in combination with fluorescence-guided surgery on a pancreatic cancer patient-derived orthotopic xenograft (PDOX). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3486. doi:10.1158/1538-7445.AM2014-3486

Abstract 5: Real-time in vivo imaging of osteosarcoma angiogenesis

We report here real-time color-coded imaging of osteosarcoma-induced angiogenesis in vivo. Gelfoam® (5×5 mm) treated with β fibroblast growth factor (bFGF) was initially transplanted subcutaneously in the flank of transgenic nestin-driven green fluorescent protein (ND-GFP) nude mice (n=12). In ND-GFP mice, nascent blood vessels are labeled with GFP, including those growing in Gelfoam®. Seven days after transplantation of Gelfoam®, skin flaps were made and human 143B osteosarcoma cells expressing GFP in the nucleus and red fluorescent protein (RFP) in the cytoplasm were injected into the transplanted Gelfoam®. The control group had only Gelfoam® transplanted without subsequent cancer-cell inoculation. Skin flaps were made at days 14, 21, 28 after transplantation of the Gelfoam® to allow observation of vascularization of the Gelfoam® using fluorescence imaging after both with and without cell inoculation. ND-GFP expressing nascent blood vessels penetrated and spread into the Gelfoam® in both the non-cellular control and after cancer-cell inoculation. The mean length of ND-GFP expressing blood vessels of mice with osteosarcoma cells seeded on the Gelfoam® increased compared to the Gelfoam®-only control at days 14, 21, 28 after transplantation of the Gelfoam® (at day 14, 21 ; p&lt;0.05, at day 28 ; p&lt;0.01). The results demonstrate that the osteosarcoma cells stimulated angiogenesis within the Gelfoam®. This model enables facile imaging of cancer-cell-induced angiogenesis and the study of its mechanism and inhibition.

Citation Format: Fuminari Uehara, Yasunori Tome, Hiroki Maehara, Fuminori Kanaya, Shinji Miwa, Yukihiko Hiroshima, Shuya Yano, Mako Yamamoto, Yasunori Matsumoto, Robert M. Hoffman. Real-time in vivo imaging of osteosarcoma angiogenesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5. doi:10.1158/1538-7445.AM2014-5

Abstract 1982: Invading cancer cells are mostly in G0/G1 and resist chemotherapy demonstrated by real-time FUCCI imaging of cell-cycle kinetics in Gelfoam® histoculture

Invasive cancer cells are a critical target for chemotherapy in order to prevent metastasis. In the present report, we demonstrate real-time visualization of cell-cycle kinetics of invading cancer in three-dimensional (3D) Gelfoam® histoculture. A fluorescence ubiquitination cell cycle indicator (FUCCI) was used whereby G1/G0 cells express a red fluorescent protein and S/G2/M cells express a green fluorescent protein. With FUCCI imaging, we observed that cancer cells in G0/G1 phase in Gelfoam® histoculture migrated more rapidly and further than the cancer cells in S/G2/M phase. Cancer cells ceased migrating when they entered S/G2/M phases and restarted migrating after division and re-entry into G1/G0. Migrating cancer cells also were resistant to chemotherapy since they were preponderantly in G1/G2 and cytotoxic chemotherapy targets cells in S/G2/M phase. The results of the present report suggest that novel therapy targeting G1/G2 cancer cells is necessary to prevent metastasis.

Citation Format: Shuya Yano, Shinji Miwa, Sumiyuki Mii, Yukihiko Hiroshima, Fuminari Uehara, Hiroyuki Kishimoto, Hiroshi Tazawa, Ming Zhao, Michael Bouvet, Toshiyoshi Fujiwara, Robert M. Hoffman. Invading cancer cells are mostly in G0/G1 and resist chemotherapy demonstrated by real-time FUCCI imaging of cell-cycle kinetics in Gelfoam® histoculture. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1982. doi:10.1158/1538-7445.AM2014-1982

Abstract 4375: UVC irradiation in combination with fluorescence-guided surgery cures metastatic human pancreatic cancer in orthotopic mouse models

The aim of this study was to determine the efficacy of UVC irradiation in combination with fluorescence-guided surgery (FGS) in an orthotopic model of pancreatic cancer. Two weeks after orthotopic implantation of human MiaPaCa-2-GFP pancreatic cancer cells, bright-light surgery (BLS) was performed on all tumor-bearing mice (n=24). Postoperatively, the surgical resection bed was imaged with the OV100 variable magnification imaging system with a magnification of 0.56x to detect residual tumor. The mice which underwent BLS were randomized into 3 groups; BLS only (n=8) or FGS (n=8) or FGS-UVC (n=8). The residual tumors were resected with FGS using a portable, hand-held imaging system. After FGS, the surgical resection bed was imaged with the OV100 with a magnification of 0.89x, to detect minimal residual tumor and was irradiated with 2700 J/m2 UVC (emission peak 254 nm) from the bottom of a chamber using a Benchtop 3UV transilluminator (UVP, LLC, Upland, CA). The average residual tumor area after FGS was significantly smaller than BLS (0.135 ± 0.137 mm2 and 3.338 ± 2.929 mm2, respectively; p=0.007). Relapse-free survival (RFS) and overall survival (OS) were determined in 3 groups. Three-month RFS in the BLS, FGS and FGS-UVC were 0%, 50% and 100%, respectively. Five-month OS in BLS, FGS and FGS-UVC was 10%, 90% and 100%, respectively. FGS and FGS-UVC resulted in significantly increased survival compared to BLS for both RFS and OS. FGS-UVC showed significantly increased survival compared to the FGS for both RFS and OS (p=0.008 and p=0.025, respectively). These results suggests that UVC irradiation in combination with FGS could be a curative strategy for human pancreatic cancer.

Citation Format: Yukihiko Hiroshima, Ali Maawy, 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. UVC irradiation in combination with fluorescence-guided surgery cures metastatic human pancreatic cancer in orthotopic mouse models. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4375. doi:10.1158/1538-7445.AM2014-4375

Abstract 13: Color-coded imaging of vessel anastomosis in vivo using RFP and CFP transgenic mice

We previously report the development of a color-coded imaging model that can visualize the anastomosis between blood vessels of red fluorescent protein (RFP)-expressing vessels in Gelfoam® previously vascularized in RFP transgenic mice and blood vessels of nestin-driven green fluorescent protein (ND-GFP) mice that express GFP in nascent vessels (Anticancer Res. 33: 3041-3046, 2013). In the present study, fourteen days after transplantation into RFP transgenic nude mice, the Gelfoam® was removed and re-transplanted into the subcutis on the flank of cyan fluorescent protein (CFP) transgenic mice. Skin flaps were made and anastomosis between the CFP-expressing vessels and RFP blood vessels in the Gelfoam® was imaged 14 and 21 days after re-transplantation. The results presented in this and our previous report suggest a new paradigm of visualizing blood vessel anastomosis and its implications for tumor angiogenesis.

Citation Format: Fuminari Uehara, Yasunori Tome, Hiroki Maehara, Kazuhiro Tanaka, Fuminori Kanaya, Shinji Miwa, Yukihiko Hiroshima, Shuya Yano, Mako Yamamoto, Yasunori Matsumoto, Robert M. Hoffman. Color-coded imaging of vessel anastomosis in vivo using RFP and CFP transgenic mice. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 13. doi:10.1158/1538-7445.AM2014-13

Abstract 1230: Efficacy of Salmonella typhimurium A1-R and anti-VEGF therapy on a patient-derived orthotopic xenograft (PDOX) pancreatic cancer model

We have previously developed the genetically-modified Salmonella typhimurium A1-R (A1-R) strain that selectively targets tumors and demonstrated that A1-R was able to eradicate primary and metastatic tumors in monotherapy in nude mouse models of various cancers including pancreatic cancer. The aim of this study was to examine the efficacy of A1-R treatment on VEGF-positive human pancreatic cancer in a patient derived orthotopic xenograft (PDOX) model in combination with anti-VEGF therapy. A VEGF-positive human pancreatic cancer cell line (MiaPaCa-2-GFP) and VEGF-positive pancreatic cancer PDOX were orthotopically implanted in nude mice. The nude mice were treated in the following groups: (1) gemcitabine (GEM) (80 mg/kg, ip, weekly, 4 weeks); (2) GEM (80 mg/kg, ip, weekly, 4 weeks) + Bevacizumab (Bev) (5 mg/kg, ip, twice a week, 4 weeks); (3) GEM (80 mg/kg, ip, weekly, 2 weeks) + Bev (5 mg/kg, ip, twice a week, 2 weeks) → A1-R (1.5x108 CFU/body, ip, weekly, 2 weeks); and (4) saline (vehicle/control, ip, weekly, 4 weeks). The mean tumor weight of each group in the MiaPaCa-2-GFP model was as follows: (1) GEM; 775.9 ± 273.8 mg; (2) GEM/Bev; 413.5 ± 108.3 mg; (3) GEM/Bev→A1-R; 257.5 ± 57.1 mg; and (4) Control; 2655.4 ± 583.9 mg. GEM/Bev→A1-R significantly reduced tumor weight compared to GEM/Bev treatment in the MiaPaCa-2-GFP model (p=0.022). The tumor weight of each group in the PDOX model was as follows: (1) GEM; 263.1 ± 129.1 mg, (2) GEM/Bev; 65.9 ± 41.9 mg, (3) GEM/Bev→A1-R; 21.9 ± 6.2 mg and (4) Control; 998.8 ± 377.7 mg. GEM/Bev→A1-R significantly reduced tumor weight compared to GEM/Bev treatment in the PDOX model (p=0.029). These results demonstrate that A1-R is effective on pancreatic cancer in combination with anti-VEGF, including the PDOX model indicating the clinical potential of this combination.

Citation Format: Yukihiko Hiroshima, Ming Zhao, Matthew H.G. Katz, Jason B. Fleming, Sho Sato, Takashi Murakami, Mako Yamamoto, Fuminari Uehara, Shinji Miwa, Shuya Yano, Masashi Momiyama, Yong Zhang, Ali Maawy, Takashi Chishima, Kuniya Tanaka, Michael Bouvet, Itaru Endo, Robert M. Hoffman. Efficacy of Salmonella typhimurium A1-R and anti-VEGF therapy on a patient-derived orthotopic xenograft (PDOX) pancreatic cancer model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1230. doi:10.1158/1538-7445.AM2014-1230

Abstract 3130: Zoledronic acid inhibits proliferation and metastasis of human pancreatic cancer in the patient-derived orthotopic xenograft (PDOX) model by targeting tumor-educated macrophages

Macrophages harvested from the peritoneal cavity of nude mice with subcutaneous human pancreatic tumors were defined as “tumor-educated macrophages” (EMϕ) and macrophages harvested from mice without tumors were defined as “naïve macrophages” (NMϕ). EMϕ promote tumor growth and metastasis. The aim of the present study was to determine the efficacy of Zoledronic acid (ZA) on EMϕ in a pancreatic cancer patient derived orthotopic xenograft (PDOX) nude mouse model. In this study, EMϕ and NMϕ were compared for their ability to enhance tumor progression. We initially demonstrated that the cancer cells exposed to the conditioned medium harvested from EMϕ culture significantly increased proliferation (p = 0.016) and had more migration stimulation capability (p &lt; 0.001) compared to cultured cancer cells treated with the conditioned medium from NMϕ. Next, we examined the efficacy of ZA on EMϕ, and NMϕ and found that ZA had the ability to kill both EMϕ and NMϕ in vitro. We then demonstrated that EMϕ promoted tumor growth and metastasis in an orthotopic mouse model of a human pancreatic cancer cell line, ZA reduced the tumor growth (p = 0.006) and metastasis (p = 0.025) promoted by EMϕ. Finally, we examined the efficacy of ZA for pancreatic cancer in the PDOX model, and found that the combination of gemcitabine (GEM) and ZA reduced tumor weight (p = 0.016) and tumor growth (p = 0.005) compared to GEM alone. ZA alone reduced metastasis (p = 0.009). These results suggest that ZA inhibits the proliferation and the metastasis of human pancreatic cancer by targeting EMϕ.

Citation Format: Yukihiko Hiroshima, Mohamed K. Hassenein, Rhiana Menen, Matthew H.g. Katz, Jason B. Fleming, Sho Sato, Takashi Murakami, Mako Yamamoto, Fuminari Uehara, Shinji Miwa, Shuya Yano, Masashi Momiyama, Ali Maawy, Takashi Chishima, Kuniya Tanaka, Michael Bouvet, Itaru Endo, Robert M. Hoffman. Zoledronic acid inhibits proliferation and metastasis of human pancreatic cancer in the patient-derived orthotopic xenograft (PDOX) model by targeting tumor-educated macrophages. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3130. doi:10.1158/1538-7445.AM2014-3130

Abstract 1983: Real-time imaging of exosomes dynamic of cross-talking and cell trafficking in 3D Gelfoam® histoculture

Exosomes are small membrane vesicles (30-100 nm) released by many types of cells during normal physiological processes and are thought to play an important role in cell-to-cell communication to promote tumor metastasis. Exosomes contain diffusible factors, such as cytokines, growth factors and extracellular matrix molecules and also mediate local and systemic cell communication through the horizontal transfer of information, such as mRNAs, microRNAs and proteins. However, the exosome dynamics and trafficking between cancer cells and tumor stromal cells in a metastatic niche are still unclear. In this study, in order to image the movement of cancer cell-derived exosomes, we developed a confocal time lapse imaging system to use green fluorescent protein (GFP)-tagged CD63, which is a general marker of exosomes, expressed in breast cancer cells cultured on 3-dimentional Gelfoam® histoculture. We demonstrated that 3D Gelfoam® culture enabled imaging of structural cell-to-cell contact between neighboring cells and exosome behavior in real-time. This system makes it possible to monitor real-time exosome dynamics and cross-talking between cancer cells and other cells and to identify the mechanism of exosome release and uptake such as in a metastatic niche.

Citation Format: Mako Yamamoto, Shinji Miwa, Yukihiko Hiroshima, Shuya Yano, Fuminari Uehara, Yasunori Matsumoto, Atsushi Suetsugu, Kimi Homma, Robert M. Hoffman. Real-time imaging of exosomes dynamic of cross-talking and cell trafficking in 3D Gelfoam® histoculture. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1983. doi:10.1158/1538-7445.AM2014-1983

Abstract 1979: Three-dimensional Gelfoam® histoculture enables cancer cells to mimic in vivo cancer cell cycling as visualized with FUCCI imaging

Collagen sponge-gel histoculture was developed by Leighton (In: Encyclopedia of Life Sciences. John Wiley and Sons, Ltd.: Chichester, 2010, Published Online. DOI: 10.1002/9780470015902.a0002573.pub2). In the 1950s, Leighton showed that placing cells in histoculture enables them to form 3-dimensional structures. Because of its architectural resemblance to native tissue, sponge gel histoculture represents a unique in vivo-like model to study cancer-cell behavior (Brenner's Encyclopedia of Genetics, 2nd Ed., Vol. 7, pp. 73-76. Elsevier, 2013). For example, Leighton observed that when C3HBA mouse mammary adenocarcinoma cells were grown on sponge-matrix histoculture, the cells aggregated similar to the original in vitro tumor. Distinct structures were formed within the tumors such as lumina and stromal elements, with some of the glandular structures similar to the original tumor (above-reference). We have further developed sponge gel histoculture using Gelfoam to grow tumors, nerves, hair follicles, skin with growing hair (above-reference). In the present report, we use fluorescence ubiquitination cell cycle indicator (FUCCI) imaging and Gelfoam® collagen sponge gel histoculture to demonstrate that the cell cycle phase distribution of cancer cells in Gelfoam® and in vivo tumors is similar whereby only the surface cells proliferate and interior cells are quiescent in G1/G0. This is markedly contrary to 2D culture where most cancer cells cycle. This observation explains, at least in part, the resistance of solid tumors to chemotherapy which targets only cycling cells.

Citation Format: Shuya Yano, Shinji Miwa, Sumiyuki Mii, Yukihiko Hiroshima, Fuminari Uehara, Hiroyuki Kishimoto, Hiroshi Tazawa, Ming Zhao, Toshiyoshi Fujiwara, Robert M. Hoffman. Three-dimensional Gelfoam® histoculture enables cancer cells to mimic in vivo cancer cell cycling as visualized with FUCCI imaging. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1979. doi:10.1158/1538-7445.AM2014-1979

Abstract 1204: Establishment of a patient-derived orthotopic xenograft (PDOX) model of patient cervical cancer

We implanted a tumor resected from a patient with metastatic HER-2-positive cervical cancer from 8 NOD/SCID mice (F1; NOD/SCID-sc) and 10 nude mice (F1; Nude-sc) subcutaneously, and 8 nude mice (F1; Nude-soi) orthotopically. Five out of 8 NOD/SCID mice died within 7 days after implantation. Infections around the surgical wound, loss of weight and of lethargy were observed in post-operatively in other mice. We examined the tumor-take rate of each model 8 weeks after implantation. Tumors grew in 3 out of 3 mice in F1; NOD/SCID-sc (100 %); 7 out of 10 mice in F1; nude-sc (70 %) and 6 out of 8 mice in F1; nude-soi group (75 %), respectively. The metastatic tumors (peritoneal dissemination, liver metastasis, lung metastasis or lymph node metastasis) were detected in 4 mice in F1; nude-soi mice (50 %). We found all xenografts including the metastatic tumors had histological structures similar to the original tumor and were stained by anti-human HER-2 antibody. Next, we implanted the small fragments of subcutaneous tumors from F1; Nude-sc mice (F2; sc-sc) or the primary tumors of F1; nude-soi mice (F2; soi-sc) to another set of nude mice (20 mice each) subcutaneously, and examined the tumor-take rate of each group 4 weeks and 8 weeks after implantation. Eight mice in the F2; sc-sc group (40 %) and 16 mice in the F2; soi-sc group (80 %) had tumors at week 4, and 15 mice in the F2; sc-sc group (75 %) and 19 mice in the F2; soi-sc group (95 %) had tumors at week 8. These results suggest that PDOX in nude mouse model recapitulates the biological behaviors of the original tumor and has the sufficient tumor-take rate.

Citation Format: Yukihiko Hiroshima, Yong Zhang, Ali Maawy, Sho Sato, Takashi Murakami, Mako Yamamoto, Fuminari Uehara, Shinji Miwa, Shuya Yano, Masashi Momiyama, Takashi Chishima, Kuniya Tanaka, Ali Maawy, Itaru Endo, Robert M. Hoffman. Establishment of a patient-derived orthotopic xenograft (PDOX) model of patient cervical cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1204. doi:10.1158/1538-7445.AM2014-1204

Abstract 2403: Imaging of UVB and UVC-induced DNA damage repair in cancer cells in Gelfoam histoculture and minimal cancer in mice

We compared the DNA damage repair response of cancer cells after UVB or UVC irradiation. The DNA-damage repair response to UV irradiation was imaged in tumors growing in 3D Gelfoam® histoculture and in superficial tumors grown in mice. UV-induced DNA damage repair was imaged with GFP fused to the DNA damage response (DDR)-related chromatin-binding protein 53BP1 in MiaPaCa-2 human pancreatic cancer cells. 53BP1 forms foci during DNA damage repair. A clonogenic assay initially showed that UVC and UVB inhibited MiaPaCa-2 cell proliferation in a dose-dependent manner, with UVC having more efficacy. Gelfoam® histocultures and confocal imaging enabled 53BP1-GFP nuclear foci to be observed within 1 h after UV irradiation, indicating the onset of DNA damage repair response. Induction of UVB-induced 53BP1-GFP focus formation was observed up to a depth of 120 µm in MiaPaCa-2 cells on Gelfoam®, while UVC induced foci only to a depth of 40 µm. The MiaPaCa-2 cells irradiated by both UVB and UVC light in a skin-flap mouse model had a significant decrease in tumor growth compared to untreated controls. Moreover, UVB-treatment had greater inhibition of tumor growth compared to UVC. Our results demonstrate that both UVB and UVC are useful tools for the treatment of residual cancer, and UVB was more effective than UVC in vivo, possibly due to greater tissue penetration of UVB because of its longer wavelength.

Citation Format: Fuminari Uehara, Shinji Miwa, Yasunori Tome, Hiroki Maehara, Fuminori Kanaya, Yukihiko Hiroshima, Shuya Yano, Mako Yamamoto, Yasunori Matsumoto, Elena V. Efimova, Robert M. Hoffman. Imaging of UVB and UVC-induced DNA damage repair in cancer cells in Gelfoam histoculture and minimal cancer in mice. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2403. doi:10.1158/1538-7445.AM2014-2403

Osteosarcoma cells enhance angiogenesis visualized by color-coded imaging in the in vivo Gelfoam® assay

We previously described a color-coded imaging model that can quantify the length of nascent blood vessels using Gelfoam® implanted in nestin-driven green fluorescent protein (ND-GFP) nude mice. In ND-GFP mice, nascent blood vessels are labeled with GFP. We report here that osteosarcoma cells promote angiogenesis in the Gelfoam® angiogenesis assay in ND-GFP mice. Gelfoam® was initially transplanted subcutaneously in the flank of transgenic ND-GFP nude mice. Seven days after transplantation of Gelfoam®, skin flaps were made and human 143B osteosarcoma cells expressing green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in cytoplasm were injected into the transplanted Gelfoam®. The control-group mice had only implanted Gelfoam®. Skin flaps were made at days 14, 21, and 28 after transplantation of the Gelfoam® to allow imaging of vascularization in the Gelfoam® using a variable-magnification small animal imaging system and confocal fluorescence microscopy. ND-GFP expressing nascent blood vessels penetrated and spread into the Gelfoam® in a time-dependent manner in both control and osteosarcoma-implanted mice. ND-GFP expressing blood vessels in the Gelfoam® of the osteosarcoma-implanted mice were associated with the cancer cells and larger and longer than in the Gelfoam®-only implanted mice (P < 0.01). The results presented in this report demonstrate strong angiogenesis induction by osteosarcoma cells and suggest this process is a potential therapeutic target for this disease.

Efficacy of Salmonella typhimurium A1-R versus chemotherapy on a pancreatic cancer patient-derived orthotopic xenograft (PDOX)

The aim of this study is to determine the efficacy of tumor-targeting Salmonella typhimurium A1-R (A1-R) on pancreatic cancer patient-derived orthotopic xenografts (PDOX). The PDOX model was originally established from a pancreatic cancer patient in SCID-NOD mice. The pancreatic cancer PDOX was subsequently transplanted by surgical orthotopic implantation (SOI) in transgenic nude red fluorescent protein (RFP) mice in order that the PDOX stably acquired red fluorescent protein (RFP)-expressing stroma for the purpose of imaging the tumor after passage to non-transgenic nude mice in order to visualize tumor growth and drug efficacy. The nude mice with human pancreatic PDOX were treated with A1-R or standard chemotherapy, including gemcitabine (GEM), which is first-line therapy for pancreatic cancer, for comparison of efficacy. A1-R treatment significantly reduced tumor weight, as well as tumor fluorescence area, compared to untreated control (P = 0.011), with comparable efficacy of GEM, CDDP, and 5-FU. Histopathological response to treatment was defined according to Evans's criteria and A1-R had increased efficacy compared to standard chemotherapy. The present report is the first to show that A1-R is effective against a very low-passage patient tumor, in this case, pancreatic cancer. The data of the present report suggest A1-1 will have clinical activity in pancreatic cancer, a highly lethal and treatment-resistant disease and may be most effectively used in combination with other agents.

Fluorescence-guided surgery in combination with UVC irradiation cures metastatic human pancreatic cancer in orthotopic mouse models

The aim of this study is to determine if ultraviolet light (UVC) irradiation in combination with fluorescence-guided surgery (FGS) can eradicate metastatic human pancreatic cancer in orthotopic nude–mouse models. Two weeks after orthotopic implantation of human MiaPaCa-2 pancreatic cancer cells, expressing green fluorescent protein (GFP), in nude mice, bright-light surgery (BLS) was performed on all tumor-bearing mice (n = 24). After BLS, mice were randomized into 3 treatment groups; BLS-only (n = 8) or FGS (n = 8) or FGS-UVC (n = 8). The residual tumors were resected using a hand-held portable imaging system under fluorescence navigation in mice treated with FGS and FGS-UVC. The surgical resection bed was irradiated with 2700 J/m² UVC (254 nm) in the mice treated with FGS-UVC. The average residual tumor area after FGS (n = 16) was significantly smaller than after BLS only (n = 24) (0.135±0.137 mm² and 3.338±2.929 mm², respectively; p = 0.007). The BLS treated mice had significantly 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). FGS-UVC-treated mice had increased RFS and OS compared to FGS-only treated mice (p = 0.008 and p = 0.025, respectively); with RFS lasting at least 150 days indicating the animals were cured. The results of the present study suggest that UVC irradiation in combination with FGS has clinical potential to increase survival.