Preclinical testing using tumors from genetically engineered mouse mammary models

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 10067-10067
Author(s):  
L. Varticovski ◽  
M. G. Hollingshead ◽  
M. R. Anver ◽  
A. I. Robles ◽  
J. E. Green ◽  
...  

10067 Background: Mouse models have been used extensively in preclinical testing of anticancer drugs. However, few of these models reflect the progression of human disease, and even fewer predict the performance of these drugs in clinical trials. Testing anticancer therapies in genetically engineered mouse (GEM) holds the promise of improving preclinical models and guiding the design of clinical trials. Unfortunately, the use of tumor-bearing GEM is hampered by the difficulty in simultaneously obtaining sufficient numbers of animals with the same stage of tumor development. The additional complexity in testing breast cancer therapies in the mouse is that all 10 mammary glands can develop tumors, frequently at different times. Methods: To circumvent the variable tumor latency and lack of synchrony in GEM, we transplanted tumor fragments or cell suspensions from multiple mammary tumor-bearing GEM into the mammary fat pad or subcutaneously into naïve syngeneic, immunodeficient athymic nude, or scid mice. Results: Tumors transplanted as fragments or cell suspensions derived from anterior mammary gland grew faster than the posterior tumors for serial passages without any significant morphologic differences. Cell suspensions using fresh or frozen cells were equally effective in generating tumors, and increasing the numbers of transplanted cells resulted in faster tumor growth. The transplantation strategy was reproducible in multiple breast cancer mouse models, including MMTV-PyMT, -Her2/neu, -wnt1/p53, BRCA1/p53, and others. Metastatic disease in the lungs was evident after removing the primary tumors at different rates for each mouse model. The transplanted primary tumors and the tumors arising in the original GEM had similar morphologic appearance and sensitivity to several chemotherapeutic and novel molecular targeted agents. Conclusions: We have established transplantable synchronous mammary tumors from GEM which also develop metastatic disease. These valuable mouse models are suitable for studying tumor-host interactions, tumor progression, and preclinical testing in a well-characterized molecular and genetic background. Testing these GEM tumors for conventional and novel molecular targeted therapies will be discussed. No significant financial relationships to disclose.

2021 ◽  
Vol 10 (11) ◽  
pp. 2340
Author(s):  
Lucia Borriello ◽  
John Condeelis ◽  
David Entenberg ◽  
Maja H. Oktay

Although metastatic disease is the primary cause of mortality in cancer patients, the mechanisms leading to overwhelming metastatic burden are still incompletely understood. Metastases are the endpoint of a series of multi-step events involving cancer cell intravasation, dissemination to distant organs, and outgrowth to metastatic colonies. Here we show, for the first-time, that breast cancer cells do not solely disseminate to distant organs from primary tumors and metastatic nodules in the lymph nodes, but also do so from lung metastases. Thus, our findings indicate that metastatic dissemination could continue even after the removal of the primary tumor. Provided that the re-disseminated cancer cells initiate growth upon arrival to distant sites, cancer cell re-dissemination from metastatic foci could be one of the crucial mechanisms leading to overt metastases and patient demise. Therefore, the development of new therapeutic strategies to block cancer cell re-dissemination would be crucial to improving survival of patients with metastatic disease.


2007 ◽  
Vol 13 (7) ◽  
pp. 2168-2177 ◽  
Author(s):  
Lyuba Varticovski ◽  
Melinda G. Hollingshead ◽  
Ana I. Robles ◽  
Xiaolin Wu ◽  
James Cherry ◽  
...  

2013 ◽  
Vol 7 (2) ◽  
pp. 146-164 ◽  
Author(s):  
Sjoerd Klarenbeek ◽  
Martine H. van Miltenburg ◽  
Jos Jonkers

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e15503-e15503
Author(s):  
Jun Lin ◽  
Ru Li ◽  
Yujie Huang

e15503 Background: Metastatic breast cancer is a pressing health concern worldwide. Various treatments have been developed but no significant long-term changes in overall survival are observed. Therefore, there is a demand to improve current therapies to treat this disease. Surgical resection of the primary tumors is essential in the treatment. However, accumulating evidence alludes to a role for volatile anesthetics which are used during the surgery in metastatic tumor development, but the mechanism remains largely unknown. We have shown anesthetics exert different effects on lung metastasis in mouse models of breast cancers. This study analyses the effect of general anesthetics in lung microenvironment associated with the increased metastases. Methods: Balb/c mice and NOD-SCID mice were orthotopically implanted with 4T1 cells and MDA-MB-231 cells respectively, in the mammary fat pad to generate primary tumors. Mice were subjected to the tested anesthetic during implantation and/or before and after surgery. Surgical dissection of primary tumor was performed under anesthesia with sevoflurane or an intravenous anesthetic propofol. Survival curve was constructed and analysed. Mice were euthanized to harvest tissues for histology and cell analysis. Results: As we previously reported, surgical dissection of primary tumor in mice under anesthesia with sevoflurane led to significantly more lung metastasis than with propofol in both syngeneic murine 4T1 and xenograft human MDA-MB-231 breast cancer models. Sevoflurane was associated with increased IL6(Li, Huang, & Lin, 2020). Here we show that anesthesia with sevoflurane resulted in changes of stroma composition in the lung, which was reversed by IL6 pathway interruption. Conclusions: Those results contribute to our understanding of effects of sevoflurane on cancer metastasis and suggest a potential therapeutic approach to overcome the risk of general anesthesia. Li, R., Huang, Y., & Lin, J. (2020). Distinct effects of general anesthetics on lung metastasis mediated by IL-6/JAK/STAT3 pathway in mouse models. Nat Commun, 11, 642.


2021 ◽  
Vol 23 (Supplement_1) ◽  
pp. i20-i20
Author(s):  
Maria Guerra Garcia ◽  
Katherine Deland ◽  
Lixia Luo ◽  
Yan Ma ◽  
Nerissa Williams ◽  
...  

Abstract Diffuse midline gliomas (DMGs) are responsible for a large proportion of childhood brain tumor deaths. Currently, radiation therapy is thought to be one of the most effective treatment options, but more than 90% of children still die within 2 years of diagnosis. DMGs are defined by somatic histone 3 K27M (H3K27M) mutations that have been shown to promote the G0/G1 to S cell cycle transition. The majority of DMGs also contain loss-of-function mutations in TP53. Prior research demonstrated that orthotopic xenograft and primary mouse models of non-H3K27M-mutated gliomas with inactivation of p53 are preferentially radiosensitized by inactivation of Ataxia Telangiectasia Mutated (ATM), a kinase that mediates DNA repair in response to DNA damage caused by radiation. The high frequency of mutations that deregulate p53 in DMGs raises the possibility that H3K27M-mutant DMGs may also be radiosensitized by ATM inhibition, representing a unique therapeutic opportunity. Here, we hypothesize that H3K27M-mutant DMGs that have loss of function of p53 will be radiosensitized by loss of ATM. To test this hypothesis, we used the RCAS-TVA viral gene delivery system to generate genetically-faithful primary mouse models of H3K27M-mutant DMG with p53 deletion, and we used Cre recombinase to delete Atm in the tumor cells of these mice and generated littermate controls that retained Atm. Mice were imaged weekly via luciferase-based bioluminescence to track tumor development and irradiated with three daily fractions of 10 Gy after tumor detection. We subsequently quantified the survival of mice without neurological decline following irradiation. In separate cohorts, we collected primary tumors after irradiation to verify H3K27M expression and to assess cell cycle arrest and mechanisms of cell death. These studies will elucidate mechanisms by which ATM inactivation can radiosensitize H3K27M-mutant DMGs with nonfunctioning p53, which will guide the design of clinical trials testing ATM inhibitors in DMG patients.


Author(s):  
Siavash Mashhouri ◽  
Erfan Yarahmadi ◽  
Seyyed Meysam Abtahi Froushani

Background: The potential of Candida albicans to modulate antigen-presenting cells maturation has been documented in past studies. Dendritic cells are critical modulators in the orchestration of adaptive immune responses alongside myeloid subtypes, which play an important role in the presentation of antigens to T cells. The aim of this study was to evaluate the efficacy of splenocytes activated with the extract of heated 4T1 cells and the yeast form of C. albicans against breast cancer growth in vivo. Methods: 4T1 cells were subcutaneously injected into the left flanks of female BALB/c mice (n=40). At a time when palpable tumors had developed, experimental groups were immunized twice at one-week interim with either activated splenocytes with the extract of heated 4T1 or the killed preparation of yeast form of C. albicans or a combination of the two-One week after the second injection, one-half of animals (n=20) were euthanized to investigate the immune response profile. Results: Administration of activated splenocytes with the combination protocol caused a favorable survival curve and slower rates of tumor development compared to other tumor-bearing mice. Moreover, combination therapy significantly increased the secretion of IFN-γ, respiratory burst and nitric oxide production and conversely diminished the secretion of IL-4, IL-10 and TGF-β in the splenocyte population. Conclusion: Since the murine 4T1 cell line is similar to the final stage of human breast carcinoma, we postulate that activated splenocytes with the extract of heated 4T1 cells and yeast form of C. albicans can reduce tumor development in tumor-bearing mice.


Sign in / Sign up

Export Citation Format

Share Document