Imaging-Guided Evaluation of the Novel Small-Molecule Benzosuberene Tubulin-Binding Agent KGP265 as a Potential Therapeutic Agent for Cancer Treatment

The selective disruption of tumor-associated vasculature represents an attractive therapeutic approach. We have undertaken the first in vivo evaluation of KGP265, a water-soluble prodrug of a benzosuberene-based tubulin-binding agent, and found promising vascular-disrupting activity in three distinct tumor types. Dose escalation in orthotopic MDA-MB-231-luc breast tumor xenografts in mice indicated that higher doses produced more effective vascular shutdown, as revealed by dynamic bioluminescence imaging (BLI). In syngeneic orthotopic 4T1-luc breast and RENCA-luc kidney tumors, dynamic BLI and oxygen enhanced multispectral optoacoustic tomography (OE-MSOT) were used to compare vascular shutdown following the administration of KGP265 (7.5 mg/kg). The BLI signal and vascular oxygenation response (ΔsO2) to a gas breathing challenge were both significantly reduced within 2 h, indicating vascular disruption, which continued over 24 h. A correlative histology confirmed increased necrosis and hemorrhage. Twice-weekly doses of KGP265 caused significant growth delay in both MDA-MB-231 and 4T1 breast tumors, with no obvious systemic toxicity. A combination with carboplatin produced significantly greater tumor growth delay than carboplatin alone, though significant carboplatin-associated toxicity was observed (whole-body weight loss). KGP265 was found to be effective at low concentrations, generating long-term vascular shutdown and tumor growth delay, thus providing strong rationale for further development, particularly in combination therapies.

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Effect of Dose, Timing and Delivery of Tumor Necrosis Factor Alpha as an Adjuvant in Cryosurgery of ELT-3 Uterine Leiomyoma (Fibroid) Tumor

Journal of Medical Devices ◽

10.1115/1.3147380 ◽

2009 ◽

Vol 3 (2) ◽

Author(s):

J. Jiang ◽

J. Bischof

Keyword(s):

Tumor Growth ◽

Uterine Fibroid ◽

Tumor Size ◽

Uterine Leiomyoma ◽

Mode Of Delivery ◽

Growth Delay ◽

Tumor Growth Delay ◽

Tnf Α ◽

Pre Treatment

Uterine leiomyoma (fibroid or myoma) is the most common indication for hysterectomy in premenopausal women. Cryomyolysis is a uterus sparing procedure in which a myoma is frozen by a cryoprobe, thereby causing tissue necrosis upon thawing and eventual reduction in myoma size. Unfortunately, although the iceball is readily visualized (by ultrasound-US or magnetic resonance-MR), the tissue at the periphery of the iceball is not completely destroyed. One potential solution to this problem is the use of cryosurgical adjuvants that increase cryosurgical image guidance and efficacy. Previous work in our lab has shown that TNF-α (native or as the nanodrug, CYT-6091, Cytimmune Sciences, Inc.) can act synergistically with cryosurgery to destroy all prostate cancer within an iceball. Building on this work, the current study was designed to test TNF-α as an adjuvant in an in vivo model of uterine fibroid (ELT-3) in a nude mouse. The aims of this study are to characterize in vivo: 1) the destruction of the uterine fibroid over time after cryosurgery; 2) the effect of TNF-α pre-treatment on enhancement of cryosurgery; 3) the effect of TNF-α dose, pre-treatment time and mode of delivery on the above and to note any toxicities. ELT–3 rat uterine fibroid cells were grown in the hind limb of female nude mice. TNF-α at various dose (2μg and 5μg) was administered at 1, 2 and 4 hours before cryotreatment in native or CYT-6091. Native TNF-α was injected either intra-tumorally or peri-tumorally. Injecting TNF-α solution into the center of the tumor comprised the intra-tumoral approach. For peri-tumoral injection, TNF-α solution was injected at each one of eight evenly distributed points spanning the circumference of the tumor base. CYT-6091 was administered by i.v. injection only. Cryosurgery was performed with a modified 1 mm diameter cryoprobe tip (−120°C). Freezing was allowed to continue to the visible edge of the tumor. Injury was assessed by measuring tumor-growth delay. Baseline tumor size was measured on day 0; fold-changes in tumor size are reported relative to size at day 0. Toxicity was evaluated by survival rate. Groups were 4–6 animals in each group. The data suggests that pre-treatment with TNF-α before cryosurgery significantly enhances visually guided destruction of uterine leiomyoma, and that the dose, timing and mode of delivery are important variables in optimization of this combination treatment. First, it was observed that at least four hours pretreatment with TNF-α is required to obtain the synergistic effect of TNF-α and cryoinjury. Second, peri-tumoral injection of native TNF-α, was the most effective delivery method to enhance cryoinjury at low dose (2μg), however it was also the most toxic method at high dose (5μg). On the other hand, CYT-6091, although less effective than peri-tumoral injection at 2μg, was the safest delivery mode (0% lethality at 2μg; 33% at 5μg). Finally, CYT-6091 delivery at 5μg with cryosurgery resulted in a dramatic tumor growth delay compared with cryosurgery alone. Therefore, i.v. injection of CYT-6091 followed by cryosurgery allowed the highest dose of TNF-α, the least toxicity and the best overall myoma reduction. Funding: R01 CA075284, American Medical Systems, Inc. TNF-α and CYT-6091: Cytimmune Sciences, Inc.

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TRU-016, An Anti-CD37 SMIP™ Biologic, In Combination with Other Therapeutic Drugs In Models of Non-Hodgkin's Lymphoma

Blood ◽

10.1182/blood.v116.21.3931.3931 ◽

2010 ◽

Vol 116 (21) ◽

pp. 3931-3931 ◽

Cited By ~ 4

Author(s):

Paul A. Algate ◽

Jennifer Wiens ◽

Christy Nilsson ◽

Mien Sho ◽

Debra T. Chao ◽

...

Keyword(s):

Tumor Growth ◽

Follicular Lymphoma ◽

B Cell ◽

Cell Lymphoma ◽

Combination Index ◽

Growth Delay ◽

Tumor Growth Delay ◽

B Cell Malignancies

Abstract Abstract 3931 Background: CD37 is a 50–55 kDa heavily glycosylated member of the tetraspanin superfamily of molecules. This cell surface protein is expressed on normal and transformed B-cells, and has been implicated in diverse processes including cellular activation and proliferation, cell motility, and cell-cell adhesion. TRU-016 is a novel humanized anti-CD37 SMIP™ protein. Pre-clinical studies have demonstrated that anti-CD37 SMIP™ protein mediates caspase-independent direct killing of normal and malignant B-cells, a mechanism of action that appears to be different than CD20 therapies. In addition, TRU-016 results in indirect killing through NK cell mediated SMIP-protein directed cellular cytotoxicity (SDCC). The therapeutic potential of TRU-016 against several subsets of B-cell malignancies is currently being investigated in the clinic. Methods: The ability of TRU-016 to interact and increase cell killing with established therapeutics rituximab (anti-CD20 antibody), bendamustine (bi-functional alkylating agent/nucleoside analog), LY294002 (PI3K inhibitor) and temsirolimus (mTOR inhibitor) was investigated in vitro using the Rec-1 (mantle cell lymphoma) and SU-DHL-6 (diffuse large B cell lymphoma) cell lines. Individual drugs were tested in combination with TRU-016 as well as in a multiple drug cocktail. Combination index analyses were performed for drug combinations over the 20–90% effect levels. To determine whether in vitro synergy could be recapitulated in vivo, DoHH-2 (follicular lymphoma) xenografts were treated with TRU-016, bendamustine, and the combination of TRU-016 and bendamustine with or without rituximab. Furthermore, the effect of the dosing schedule with the combination of TRU-016 and rituximab was explored by comparing the treatment over a short time period to an extended (maintenance) dosing regimen. CD37 expression on the tumor xenografts was evaluated post different treatment by immunohistochemistry. Results: Combination index analyses determined that the killing effects of TRU-016 was synergistic with rituximab, bendamustine and temsirolimus in NHL models. Furthermore, TRU-016 provided additional efficacy when added to the combination of rituximab and bendamustine. In vivo results demonstrated that the in vitro synergy results were applicable to a more complex in vivo disease model. The combination of TRU-016 with bendamustine or rituximab resulted in increased tumor growth delay compared to that attained with the individual drugs. The addition of TRU-016 to the combination of bendamustine and rituximab resulted in increased tumor growth delay compared to the two drugs alone. The observed efficacy of the combination of TRU-016 and rituximab could be extended with repeated (maintenance) dosing with tumor free survival being observed beyond the 35 days of dosing. The combination of TRU-016 with temsirolimus also resulted in a reduction of tumor growth compared to either molecule alone. CD37 target expression was detected in the xenograft tumors post-treatment with all drugs tested. Conclusions: TRU-016 in combination with rituximab, bendamustine or temsirolimus increased cell killing of NHL cells in vitro over that observed for each agent alone. Furthermore, the triple combination of TRU-016 with rituximab, bendamustine or temsirolimus displayed greater anti-tumor activity in vivo than each of the agents alone against a follicular lymphoma tumor model. The addition of TRU-016 to a combination of rituximab and bendamustine resulted in increased killing in vitro and in vivo. The combinatorial activity of TRU-016 and rituximab in vivo was increased when the drugs were administered over a longer period. These results provide preclinical rationale for the potential different combinations of TRU-016 with several established therapeutics for the treatment of NHL and related B-cell malignancies. Disclosures: Algate: Trubion Pharmaceuticals: Employment. Wiens:Trubion Pharmaceuticals: Employment. Nilsson:Trubion Pharmaceuticals: Employment. Sho:Facet/Abbott: Employment. Chao:Facet/Abbott: Employment. Starling:Facet/Abbott: Employment. Gordon:Trubion Pharmaceuticals: Employment.

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Electrochemotherapy by pulsed electromagnetic field treatment (PEMF) in mouse melanoma B16F10 in vivo

Radiology and Oncology ◽

10.1515/raon-2016-0014 ◽

2016 ◽

Vol 50 (1) ◽

pp. 39-48 ◽

Cited By ~ 19

Author(s):

Simona Kranjc ◽

Matej Kranjc ◽

Janez Scancar ◽

Jure Jelenc ◽

Gregor Sersa ◽

...

Keyword(s):

Electromagnetic Field ◽

Tumor Growth ◽

Combined Treatment ◽

Drug Uptake ◽

Growth Delay ◽

Pulsed Electromagnetic Field ◽

Tumor Growth Delay ◽

Mouse Melanoma ◽

Pulsed Electromagnetic

Introduction Pulsed electromagnetic field (PEMF) induces pulsed electric field, which presumably increases membrane permeabilization of the exposed cells, similar to the conventional electroporation. Thus, contactless PEMF could represent a promising approach for drug delivery. Materials and methods Noninvasive electroporation was performed by magnetic field pulse generator connected to an applicator consisting of round coil. Subcutaneous mouse B16F10 melanoma tumors were treated with intravenously injection of cisplatin (CDDP) (4 mg/kg), PEMF (480 bipolar pulses, at frequency of 80 Hz, pulse duration of 340 μs) or with the combination of both therapies (electrochemotherapy − PEMF + CDDP). Antitumor effectiveness of treatments was evaluated by tumor growth delay assay. In addition, the platinum (Pt) uptake in tumors and serum, as well as Pt bound to the DNA in the cells and Pt in the extracellular fraction were measured by inductively coupled plasma mass spectrometry. Results The antitumor effectiveness of electrochemotherapy with CDDP mediated by PEMF was comparable to the conventional electrochemotherapy with CDDP, with the induction of 2.3 days and 3.0 days tumor growth delay, respectively. The exposure of tumors to PEMF only, had no effect on tumor growth, as well as the injection of CDDP only. The antitumor effect in combined treatment was related to increased drug uptake into the electroporated tumor cells, demonstrated by increased amount of Pt bound to the DNA. Approximately 2-fold increase in cellular uptake of Pt was measured. Conclusions The obtained results in mouse melanoma model in vivo demonstrate the possible use of PEMF induced electroporation for biomedical applications, such as electrochemotherapy. The main advantages of electroporation mediated by PEMF are contactless and painless application, as well as effective electroporation compared to conventional electroporation.

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Using First-Passage Times to Analyze Tumor Growth Delay

Mathematics ◽

10.3390/math9060642 ◽

2021 ◽

Vol 9 (6) ◽

pp. 642

Author(s):

Patricia Román-Román ◽

Sergio Román-Román ◽

Juan José Serrano-Pérez ◽

Francisco Torres-Ruiz

Keyword(s):

Tumor Growth ◽

Tumor Volume ◽

Cox Regression ◽

First Passage Time ◽

Growth Delay ◽

Random Environments ◽

Tumor Growth Delay ◽

First Passage ◽

Time Required

A central aspect of in vivo experiments with anticancer therapies is the comparison of the effect of different therapies, or doses of the same therapeutic agent, on tumor growth. One of the most popular clinical endpoints is tumor growth delay, which measures the effect of treatment on the time required for tumor volume to reach a specific value. This effect has been analyzed through a variety of statistical methods: conventional descriptive analysis, linear regression, Cox regression, etc. We propose a new approach based on stochastic modeling of tumor growth and the study of first-passage time variables. This approach allows us to prove that the time required for tumor volume to reach a specific value must be determined empirically as the average of the times required for the volume of individual tumors to reach said value instead of the time required for the average volume of the tumors to reach the value of interest. In addition, we define several measures in random environments to compare the time required for the tumor volume to multiply k times its initial volume in control, as well as treated groups, and the usefulness of these measures is illustrated by means of an application to real data.

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Evaluation of absorbed dose distribution in melanoma B16F10 during contrast enhanced radiotherapy with intratumoral administration of dose-enhancing agent

Bulletin of Russian State Medical University ◽

10.24075/brsmu.2018.062 ◽

2018 ◽

pp. 60-64

Author(s):

AA Lipengolts ◽

ES Vorobyeva ◽

AA Cherepanov ◽

MA Abakumov ◽

TO Abakumova ◽

...

Keyword(s):

Tumor Growth ◽

Tumor Volume ◽

Absorbed Dose ◽

Growth Delay ◽

Ct Scanner ◽

Tumor Growth Delay ◽

Contrast Enhanced ◽

Melanoma B16f10 ◽

Absorbed Radiation Dose

Contrast-enhanced radiotherapy (CERT) is a binary treatment modality in which the absorbed radiation dose is not only determined by the parameters of the external radiation source but also affected by the concentration of a dose-enhancing agent (DEA) in the studied object. In this work we assessed the distribution of the absorbed dose in a murine B16F10 melanoma injected with a single dose of an aqueous Bi-DTPA solution. The mice were exposed to a single fraction of X-ray irradiation for 28.5 min. In vivo measurements of DEA concentrations were done on a micro-CT scanner using the radiopacity values of malignant tissues from the obtained CT images. We found that the presence of DEA enhanced the absorbed dose more than twofold in 6% of the tumor volume; in 29% of the tumor volume the absorbed dose increased more than onefold. The tumor growth delay time calculated for our model was 0.76 days (we only accounted for the damage caused directly by radiation), whereas in our previous research study tumor growth delay was 10 days. This discrepancy may indicate that in the tumors exposed to contrast-enhanced radiotherapy growth delay results from both the damage directly caused by radiation and other antitumor mechanisms.

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In Vivo Studies in NCT with a Boronated Porphyrin and Tumor Growth Delay as an End Point

Advances in Neutron Capture Therapy ◽

10.1007/978-1-4615-2978-1_108 ◽

1993 ◽

pp. 535-539 ◽

Cited By ~ 3

Author(s):

B. H. Laster ◽

S. B. Kahl ◽

L. Warkentien ◽

V. P. Bond

Keyword(s):

Tumor Growth ◽

In Vivo Studies ◽

Growth Delay ◽

Tumor Growth Delay ◽

End Point

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Darbepoetin alfa Radiosensitizes Tumors Independent of Anemia or the Correction of Anemia.

Blood ◽

10.1182/blood.v104.11.1637.1637 ◽

2004 ◽

Vol 104 (11) ◽

pp. 1637-1637

Author(s):

Shoucheng Ning ◽

Sinclair Angus ◽

Hartley Cynthia ◽

Knox Susan4

Keyword(s):

Tumor Growth ◽

Tumor Cells ◽

Fold Increase ◽

Growth Delay ◽

Local Tumor ◽

Tumor Growth Delay ◽

Tumor Bearing ◽

Tumor Irradiation

Abstract Darbepoetin alfa (DA) is a FDA approved long acting erythropoietic protein. We hypothesized that correction of anemia in tumor-bearing mice by DA would secondarily increase the tumor pO2 and potentiate radiation-induced cell killing of tumor cells. To test this hypothesis, we used total body irradiation (TBI) to induce anemia in C3H mice. Murine squamous cell carcinoma tumor (SCC VII) and fibrosarcoma (RIF-1) models were used to study tumor responses to radiation in vivo. DA (30μg/kg) was administered i.p. either every two weeks or weekly. EPO-R RNA levels were measured in tumors from normal, anemic and DA treated mice in both tumor models. Tumors were locally irradiated with daily fractions of 250 cGy for 5 days. Following 500 cGy TBI, hemoglobin levels decreased and reached a nadir of 7.0 ± 0.9 gm/dL 14 days post TBI. Administration of DA reduced the depth and duration of anemia and improved the general health condition of anemic animals as evidenced by accelerated recovery of body weight following the TBI and maintenance of normal levels of activity compared to similarly irradiated animals not treated with DA. Mice treated with DA on the same day as the TBI had elevated hemoglobin levels with a nadir of 11.1 gm/dL on day 14 after TBI. Systemic administration of DA alone did not stimulate tumor growth in TBI-induced anemic mice. When combined with fractionated local tumor irradiation, administration of DA at any of the time points studied (18, 11, 4 and 0 days before initiation of local tumor irradiation) delayed tumor growth and increased the tumor growth delay time from 2.7 days for irradiation alone to 7.3 – 10.6 days for DA treated animals (p < 0.01). There was no statistically significant difference between tumor growth delay times for groups of mice treated with DA at various times before tumor irradiation. Although DA effectively corrected anemia in tumor-bearing mice and significantly decreased the number of hypoxic cells in the tumors as shown by EF5 staining, radiosensitization by DA was independent of the correction of anemia. EPOR RNA expression was barely detectible in tumors cultured in vitro. There were no differences in EPO-R RNA levels in tumors from anemic or DA treated mice (1–2 fold increase), although EPO-R transcription was upregulated in tumors grown in vivo compared to control tumors lines grown in vitro (40–80 fold increase). This may be due to hypoxic induction of EPO-R by tumors in vivo or expression of EPO-R by endothelial cells or infiltrating macrophages. Results from an experiment in non-anemic mice with RIF-1 tumors suggest that DA can sensitize tumor cells in non-anemic mice to radiation as well. These results support the idea that radiosensitization by DA is independent of hemoglobin and tumor pO2. It has long been assumed that anemia causes decreased tumor oxygenation and increased tumor radioresistance, and that correction of anemia would therefore increase tumor pO2, and result in enhanced radiosensitivity. However, the data presented here challenge this presumed relationship. These findings are promising and may have relevance to the treatment of patients with a variety of tumor types with radiation therapy.

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Relationship of oral glycine with radiation-induced HIF1-alpha and tumor growth delay in a prostate cancer xenograft.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.6_suppl.81 ◽

2013 ◽

Vol 31 (6_suppl) ◽

pp. 81-81

Author(s):

Elizabeth Riley Kessler ◽

Lih-Jen Su ◽

Xiaoping Yang ◽

Cem Altunbas ◽

Thomas W. Flaig ◽

...

Keyword(s):

Prostate Cancer ◽

Nitric Oxide ◽

Tumor Growth ◽

Dietary Supplementation ◽

Luciferase Reporter ◽

Growth Delay ◽

Tumor Growth Delay ◽

Clinical Role ◽

Radiation Induced

81 Background: Preclinical studies have shown that nitric oxide (NO) is produced by upregulation of inducible nitric oxide synthase (iNOS) in activated macrophages recruited to the site of cytotoxic injury from radiation or chemotherapy. NO stabilizes hypoxia-inducible factor 1-alpha (HIF1α), leading to increased vascular endothelial growth factor, thus promoting tumor angiogenesis as a recovery mechanism from the initial cytotoxic insult. Because glycine (G) suppresses macrophage activation, we hypothesized that dietary supplementation with G would inhibit HIF1α expression and enhance tumor growth delay by preventing recovery angiogenesis. Methods: PC3 cells were transfected with a HIF1α-inducible luciferase reporter and grown as nude mice xenografts. As tumors grew to 100mm3, mice were continued in 1 of 4 conditions: 1) control (C) diet ; 2) a 5%G diet; 3) C diet with ad libitum drinking water treated with L-NAME (500mg/L), an iNOS inhibitor; or 4) C diet with a single injection of carrageenan (2mg/500uL), a selective macrophagicidal agent. After 3 days tumors were irradiated with 0 Gy (sham) or 6 Gy using a 160kV source. Tumor growth and quantitative bioluminescence data were then collected (n = 4 mice/group). Results: HIF1α expression as assessed by bioluminescence increased more than two fold 4-6 days after 6 Gy (p<0.05) in the C diet group but did not significantly increase in either the L-NAME, 5%G , or carrageenan groups. Tumor growth curves for the 6 Gy L-NAME and 5%G diet groups showed a corresponding statistically significant growth delay compared to 6 Gy C diet. No clear difference in bioluminescence or growth was noted in any 0 Gy cohort. Conclusions: The results support the hypothesis that radiation injury indirectly upregulates HIF1α via an iNOS dependent pathway. Inhibition of this pathway can enhance in vivo radiation-induced tumor growth delay and can be achieved via dietary supplementation with G. Thus, dietary G supplementation might have a clinical role for patients treated with radiotherapy for prostate cancer as a non-toxic means of achieving radiosensitization.

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