scholarly journals An mTOR and VEGFR inhibitor combination arrests a doxorubicin resistant lung metastatic osteosarcoma in a PDOX mouse model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hiromichi Oshiro ◽  
Yasunori Tome ◽  
Kentaro Miyake ◽  
Takashi Higuchi ◽  
Norihiko Sugisawa ◽  
...  

AbstractIn order to identify more effective therapy for recalcitrant osteosarcoma, we evaluated the efficacy of an mTOR-VEGFR inhibitor combination on tumor growth in a unique osteosarcoma patient-derived orthotopic xenograft (PDOX) mouse model derived from the lung metastasis of an osteosarcoma patient who failed doxorubicin therapy. We also determined the efficacy of this inhibitor combination on angiogenesis using an in vivo Gelfoam fluorescence angiogenesis mouse model implanted with osteosarcoma patient-derived cells (OS-PDCs). PDOX models were randomly divided into five groups of seven nude mice. Group 1, control; Group 2, doxorubicin (DOX); Group 3, everolimus (EVE, an mTOR and VEGF inhibitor); Group 4, pazopanib (PAZ, a VEGFR inhibitor); Group 5, EVE-PAZ combination. Tumor volume and body weight were monitored 2 times a week. The in vivo Gelfoam fluorescence angiogenesis assay was performed with implanted OS-PDCs. The nude mice with implanted Gelfoam and OSPDCs also were divided into the four therapeutic groups and vessel length was monitored once a week. The EVE-PAZ combination suppressed tumor growth in the osteosarcoma PDOX model and decreased the vessel length ratio in the in vivo Gelfoam fluorescent angiogenesis model, compared with all other groups (p < 0.05). There was no significant body-weight loss in any group. Only the EVE-PAZ combination caused tumor necrosis. The present study demonstrates that a combination of an mTOR-VEGF inhibitor and a VEGFR inhibitor was effective for a DOX-resistant lung-metastatic osteosarcoma PDOX mouse model, at least in part due to strong anti-angiogenesis efficacy of the combination.

1993 ◽  
Vol 27 (3-4) ◽  
pp. 65-68 ◽  
Author(s):  
B. H. Kwa ◽  
M. Moyad ◽  
M. A. Pentella ◽  
J. B. Rose

Cryptosporidium parvum is an important patliogen of diarrlieal disease which has been implicated in several outbreaks associated with contamination of surface waters. In monitoring for C. parvum in drinking water sources, it is important to asce tain the viability, and more importantly, the infectivity of low numbers of recovered oocysts. Groups of 10 Balb/C nude (nu/nu) mice, 4-8 weeks old at time of inoculation, were infected with C. parvum oocysts from naturally infected calves and purified using Sheather's sucrose gradients. Oocysts were counted using the Merifluor IFA kit (Meridian). Each group of 10 mice were infected with 1,10,100 and 1000 oocysts respectively. Numbers of oocysts per inoculation were determined by limiting dilution, and parallel inocula were counted microscopically to ascertain the accuracy of the dilutions. Two uninfected nude mice were kept in each cage to serve as controls. Mouse stools were collected every 4 days, concentrated using the Fekal Kontrate Concentration Kit (Meridian) and oocysts were counted with a UV microscope using the Merifluor IFA Kit (Meridian). Oocyst counts were expressed in terms of number of oocyst/g feces. Mice inoculated with 1000 oocysts began to shed oocysts on day 32, mice inoculated with 100 oocysts began to shed on days 44-48, mice inoculated with 10 oocysts began to shed on days 56-60, and mice inoculated with 1 oocyst shed on days 68-88. All infected mice continued to shed oocysts intermittently and with variable oocyst counts until day 180 when the experiment was terminated. This study established that it is possible to infect nude mice with very low numbers, down to a single oocyst. We are currently in the process of correlating the nude mouse assay with other viability assays.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4683
Author(s):  
Geng-Ruei Chang ◽  
Chan-Yen Kuo ◽  
Ming-Yang Tsai ◽  
Wei-Li Lin ◽  
Tzu-Chun Lin ◽  
...  

Zotarolimus is a semi-synthetic derivative of rapamycin and an inhibitor of mammalian target of rapamycin (mTOR) signaling. Currently, zotarolimus is used to prolong the survival time of organ grafts, but it is also a novel immunosuppressive agent with potent anti-proliferative activity. Here, we examine the anti-tumor effect of zotarolimus, alone and in combination with 5-fluorouracil, on HCT-116 colorectal adenocarcinoma cells implanted in BALB/c nude mice. Compared with the control mice, mice treated with zotarolimus or zotarolimus combined with 5-FU showed retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; reduced inflammation-related factors such as IL-1β, TNF-α, and cyclooxygenase-2 (COX-2) protein; and inhibited metastasis-related factors such as CD44, epidermal growth factor receptor (EGFR), transforming growth factor β (TGF-β), and vascular endothelial growth factor (VEGF). Notably, mice treated with a combination of zotarolimus and 5-FU showed significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with mice treated with 5-FU or zotarolimus alone, indicating a strong synergistic effect. This in vivo study confirms that zotarolimus or zotarolimus combined with 5-FU can be used to retard colorectal adenocarcinoma growth and inhibit tumorigenesis. Our results suggest that zotarolimus may increase the chemo-sensitization of tumor cells. Therefore, zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents in the treatment of human colon adenocarcinoma. Future research on zotarolimus may lead to the development of new therapeutic strategies.


2021 ◽  
Vol 22 (9) ◽  
pp. 4562
Author(s):  
Ching-Feng Wu ◽  
Ching-Yang Wu ◽  
Robin Y.-Y. Chiou ◽  
Wei-Cheng Yang ◽  
Chuen-Fu Lin ◽  
...  

Zotarolimus is a semi-synthetic derivative of rapamycin and a novel immunosuppressive agent used to prevent graft rejection. The pharmacological pathway of zotarolimus restricts the kinase activity of the mammalian target of rapamycin (mTOR), which potentially leads to reductions in cell division, cell growth, cell proliferation, and inflammation. These pathways have a critical influence on tumorigenesis. This study aims to examine the anti-tumor effect of zotarolimus or zotarolimus combined with 5-fluorouracil (5-FU) on A549 human lung adenocarcinoma cell line implanted in BALB/c nude mice by estimating tumor growth, apoptosis expression, inflammation, and metastasis. We established A549 xenografts in nude mice, following which we randomly divided the mice into four groups: control, 5-FU (100 mg/kg/week), zotarolimus (2 mg/kg/day), and zotarolimus combined with 5-FU. Compared the results with those for control mice, we found that mice treated with zotarolimus or zotarolimus combined with 5-FU retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; decreased inflammation cytokines levels (e.g., IL-1β, TNF-α, and IL-6); reduced inflammation-related factors such as cyclooxygenase-2 (COX-2) protein and nuclear factor-κB (NF-κB) mRNA; enhanced anti-inflammation-related factors including IL-10 and inhibitor of NF-κB kinase α (IκBα) mRNA; and inhibited metastasis-related factors such as transforming growth factor β (TGF-β), CD44, epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF). Notably, mice treated with zotarolimus combined with 5-FU had significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with the groups of mice treated with 5-FU or zotarolimus alone. The in vivo study confirmed that zotarolimus or zotarolimus combined with 5-FU could retard lung adenocarcinoma growth and inhibit tumorigenesis. Zotarolimus and 5-FU were found to have an obvious synergistic tumor-inhibiting effect on lung adenocarcinoma. Therefore, both zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents for treatment of human lung adenocarcinoma.


2018 ◽  
Vol 25 (6) ◽  
pp. 677-686 ◽  
Author(s):  
Shani Avniel-Polak ◽  
Gil Leibowitz ◽  
Victoria Doviner ◽  
David J Gross ◽  
Simona Grozinsky-Glasberg

Patients with neuroendocrine neoplasms (NENs) often require systemic treatment, which is frequently limited by the emergence of drug resistance. mTOR inhibitors (mTORi), such as RAD001 (everolimus), have been shown to inhibit neoplasm progression. mTORi stimulates autophagy, a degradation pathway that might promote the survival of neoplasm cells that are exposed to anti-cancer therapy. Chloroquine (CQ), a well-known anti-malarial and anti-rheumatic drug, suppresses autophagy. Based on our previous results, we hypothesized that CQ may enhance the anti-tumorigenic effects of mTORi by inhibiting autophagy and we aimed to examine the anti-tumorigenic effect of CQ, alone or in combination with RAD001. We established a NEN subcutaneous xenograft mouse model and evaluated the effect of the drugs on tumor growth, mTOR pathway, autophagy and apoptosis. CQ alone and in combination with RAD001 significantly decreased neoplasm volume. Histopathological analysis revealed that the combination of CQ and RAD001 markedly inhibited mTOR activity and neoplasm cell growth, along with accumulation of autophagosomes and increased apoptosis. In conclusion, CQ enhances the anti-tumorigenic effect of RAD001 in vivo by inhibiting autophagy. Clinical trials addressing the effects of CQ therapy on neoplasm progression in patients with NENs, mainly in those treated with mTORi, are warranted.


2003 ◽  
Vol 47 (2) ◽  
pp. 529-532 ◽  
Author(s):  
Esteban C. Nannini ◽  
Suresh R. Pai ◽  
Kavindra V. Singh ◽  
Barbara E. Murray

ABSTRACT A novel glycylcycline agent, tigecycline (GAR-936), was evaluated in vivo in the mouse model of peritonitis against three Enterococcus faecalis and four Enterococcus faecium isolates with different susceptibilities to vancomycin and tetracyclines, all of which were inhibited by ≤0.125 μg of tigecycline/ml. Using a single subcutaneous dose, tigecycline displayed a protective effect (50% protective dose, ≤5.7 mg/kg of body weight) against all strains tested, including two with Tn925 (from the Tn916 family), which contains the Tet(M) tetracycline resistance determinant, as well as VanA and VanB strains. As expected, tetracycline and minocycline were ineffective against the isolates carrying Tn925.


2010 ◽  
Vol 99 (2) ◽  
pp. 165-176 ◽  
Author(s):  
Laura M. Shelton ◽  
Purna Mukherjee ◽  
Leanne C. Huysentruyt ◽  
Ivan Urits ◽  
Joshua A. Rosenberg ◽  
...  

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4513-4513
Author(s):  
Baoying Fang ◽  
Dongmei He ◽  
Yuan Zhang

Abstract A high level of expression of Bcl-2 is associated with resistance to chemotherapeutic agents and radiation in a number of tumor types, so that a drug to reduce the levels of this protein would be expected to promote apoptosis and would therefore be considered a promising chemotherapeutic agent. At present, gene repression can also be achieved in mammalian cells by using vectors to express small hairpin RNA (shRNA) with a U6 or H1 promoter under the direction of RNA polymerase III. In our lab, we have constructed a U6 promoter based vector expressing shRNA structure targeting against Bcl-2, which could effectively down-regulate Bcl-2 protein. We previously demonstrated that this Bcl-2 shRNA decreased cell proliferation and enhanced radiation-induced apoptosis in Raji cells. In this study, we investigated the synergistic effect of Bcl-2 shRNA combined with methotrexate (MTX) in Molt4, Raji cells and nude mice model bearing human lymphoma.Bcl-2 shRNA was transfected into Molt4 cells and Raji cells with Lipofectamine. At 24,48,72,96 hours after transient transfection, the expression levels of Bcl-2 mRNA and protein were detected by RT-PCR and Western blot. The inhibition of cell growth was assessed by MTT assay, counting cell number. Apoptosis was determined by morphological observation and flow cytomertry. To examine the effect of Bcl-2 shRNA on proliferation and chemosensitivity against MTX in vivo, human Raji cell line was inoculated into the skin of BALB/c nude mice to establish lymphoma model. After Molt4 and Raji cells were transfected with Bcl-2 shRNA, protein and mRNA levels of Bcl-2 obviously were decreased. MTT assays indicated that the growth of cells transfected with Bcl-2 shRNA were significantly lower than those cells with negative control shRNA and untransfected cells, respectively (P<0.05). Bcl-2 shRNA combined with MTX significantly inhibited the growth of cells (P<0.05). There was no difference in cell survival between control shRNA / MTX combination and cells treated with MTX alone. Using Giemsa staining, cells treated with Bcl-2 shRNA combined with MTX displayed changes of apoptosis. Apoptotic rates of both Molt4 and Raji cells treated with Bcl-2 shRNA combined with MTX significantly increased (P<0.05), compared with either control shRNA / MTX combination or MTX-treatment cells alone. In the assay of s.c. tumors in nude mice, tumor growth was inhibited in Bcl-2 shRNA group compared with that in negative control shRNA, and immunohistochemistry showed that Bcl-2 protein level of tumor was also decreased. The inhibition rate of tumor growth was significantly higher in tumors treated with Bcl-2 shRNA combined with MTX than in either control shRNA / MTX combination or MTX-treatment group (P<0.05). These results suggest that Bcl-2 shRNA increases MTX-induced apoptosis in Molt4 and Raji cells. Moreover, the combination of Bcl-2 shRNA and MTX produces greater antitumor effect.


2002 ◽  
Vol 46 (7) ◽  
pp. 2310-2312 ◽  
Author(s):  
Qiu N. Sun ◽  
Laura K. Najvar ◽  
Rosie Bocanegra ◽  
David Loebenberg ◽  
John R. Graybill

ABSTRACT The in vivo activities of posaconazole, itraconazole, and amphotericin B in neutropenic mice with zygomycosis were compared. The in vitro MICs of posaconazole and itraconazole for the strains of Mucor spp. used in this study ranged from 0.125 to 8 μg/ml and 0.25 to 8 μg/ml, respectively. The in vitro MIC range for amphotericin B is 0.125 to 0.25 μg/ml. At twice-daily doses of ≥15 mg/kg of body weight, posaconazole prolonged the survival of the mice and reduced tissue burden.


2002 ◽  
Vol 80 (4) ◽  
pp. 275-280 ◽  
Author(s):  
John M Stewart ◽  
Lajos Gera ◽  
Daniel C Chan ◽  
Paul A Bunn Jr. ◽  
Eunice J York ◽  
...  

Bradykinin (BK) (Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg) is an important growth factor for small-cell lung cancer (SCLC) and prostate cancer (PC). These cancers have cells of neuroendocrine origin and express receptors for a variety of neuropeptides. BK receptors are expressed on almost all lung cancer cell lines and on many PC cells. Our very potent BK antagonist B9430 (D-Arg-Arg-Pro-Hyp-Gly-Igl-Ser-D-Igl-Oic-Arg) (Hyp, trans-4-hydroxy-L-proline; Igl, α-2-indanylglycine; Oic, octahydroindole-2-carboxylic acid) is a candidate anti-inflammatory drug but does not inhibit growth of SCLC or PC. When B9430 is dimerized by N-terminal cross-linking with a suberimide linker, the product B9870 is a potent growth inhibitor for SCLC both in vitro and in vivo in athymic nude mice. Daily i.p. injection at 5 mg·kg–1·day–1 beginning on day 8 after SCLC SHP-77 cell implantation gave 65% inhibition of tumor growth. B9870 stimulates apoptosis in SCLC by a novel "biased agonist" action. We have also developed new small mimetic antagonists. BKM-570 (F5C-OC2Y-Atmp) (F5C, pentafluorocinnamic acid; OC2Y, O-2,6-dichlorobenzyl tyrosine; Atmp, 4-amino-2,2,6,6-tetramethylpiperidine) is very potent for inhibition of SHP-77 growth in nude mice. When injected daily i.p. at 5 mg·kg–1, M-570 gave 90% suppression of tumor growth. M-570 is more potent than the well-known anticancer drug cisPlatin (60% inhibition) or the recently developed SU5416 (40% inhibition) in this model. M-570 also showed activity against various other cancer cell lines in vitro (SCLC, non-SCLC, lung, prostate, colon, cervix) and inhibited growth of prostate cell line PC3 in nude mice. M-570 and related compounds evidently act in vivo through pathways other than BK receptors. These compounds have clinical potential for treatment of human lung and prostate cancers.Key words: bradykinin antagonists, cancer, inflammation, prostate cancer, small cell lung cancer.


1985 ◽  
Vol 161 (6) ◽  
pp. 1315-1325 ◽  
Author(s):  
G Schulz ◽  
L K Staffileno ◽  
R A Reisfeld ◽  
G Dennert

The simultaneous injection of monoclonal antibody 9.2.27, directed against a chondroitin sulfate proteoglycan preferentially expressed on human melanoma cells, and 2 X 10(7) mononuclear splenocytes, eradicated established, progressively growing human melanoma tumors in nude mice. Neither splenocytes nor antibody alone achieved significant tumor regression. The cells responsible for tumor elimination are most likely natural killer (NK) cells: they are present in splenocytes of T cell-deficient nude mice, and cloned cells with NK activity are able to suppress tumor growth. Moreover, splenocytes treated with anti-asialo GM1 and complement or harvested from NK-deficient C57BL/6 beige mice did not cause tumor rejection. Furthermore, treatment of BALB/c nude mice just before injection with anti-asialo GM1 antiserum, which is known to eliminate NK activity in vivo, resulted in better tumor growth. In addition, evidence is presented that cells with NK activity are probably the effectors responsible for melanoma target cell lysis in vitro: Antibody-dependent and -independent cell-mediated lysis of M21 melanoma cells was suppressed when splenocytes were preincubated with complement and antibodies specific for cell surface antigens of NK cells, i.e., anti-asialo GM1, anti-Qa5, and anti-NK1.1. Moreover, splenocytes of C57BL/6 beige mice were not able to lyse M21 cells in vitro. These results strongly support the conclusion that cells with NK activity are indeed responsible for the antibody-dependent destruction of M21 melanoma cells in vivo and in vitro.


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