Browsing by Subject "Collagen"
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Item In-depth characterization of a new patient-derived xenograft model for metaplastic breast carcinoma to identify viable biologic targets and patterns of matrix evolution within rare tumor types(Springer, 2021-08-09) Matossian, M. D.; Chang, T.; Wright, M. K.; Burks, H. E.; Elliott, S.; Sabol, R. A.; Wathieu, H.; Windsor, G. O.; Alzoubi, Madlin S.; King, C. T.; Bursavich, J. B.; Ham, A. M.; Savoie, J. J.; Nguyen, K.; Baddoo, M.; Flemington, E.; Sirenko, O.; Cromwell, E. F.; Hebert, K. L.; Lau, F.; Izadpanah, R.; Brown, H.; Sinha, S.; Zabaleta, J.; Riker, A. I.; Moroz, K.; Miele, L.; Zea, A. H.; Ochoa, A.; Bunnell, Bruce A.; Collins-Burow, B. M.; Martin, E. C.; Burow, Matthew E.Metaplastic breast carcinoma (MBC) is a rare breast cancer subtype with rapid growth, high rates of metastasis, recurrence and drug resistance, and diverse molecular and histological heterogeneity. Patient-derived xenografts (PDXs) provide a translational tool and physiologically relevant system to evaluate tumor biology of rare subtypes. Here, we provide an in-depth comprehensive characterization of a new PDX model for MBC, TU-BcX-4IC. TU-BcX-4IC is a clinically aggressive tumor exhibiting rapid growth in vivo, spontaneous metastases, and elevated levels of cell-free DNA and circulating tumor cell DNA. Relative chemosensitivity of primary cells derived from TU-BcX-4IC was performed using the National Cancer Institute (NCI) oncology drug set, crystal violet staining, and cytotoxic live/dead immunofluorescence stains in adherent and organoid culture conditions. We employed novel spheroid/organoid incubation methods (Pu.MA system) to demonstrate that TU-BcX-4IC is resistant to paclitaxel. An innovative physiologically relevant system using human adipose tissue was used to evaluate presence of cancer stem cell-like populations ex vivo. Tissue decellularization, cryogenic-scanning electron microscopy imaging and rheometry revealed consistent matrix architecture and stiffness were consistent despite serial transplantation. Matrix-associated gene pathways were essentially unchanged with serial passages, as determined by qPCR and RNA sequencing, suggesting utility of decellularized PDXs for in vitro screens. We determined type V collagen to be present throughout all serial passage of TU-BcX-4IC tumor, suggesting it is required for tumor maintenance and is a potential viable target for MBC. In this study we introduce an innovative and translational model system to study cell-matrix interactions in rare cancer types using higher passage PDX tissue.Item Osteogenesis Imperfecta: An analysis of the inner ear development in Mus musculus (house mouse) with comments on hearing quality(2022-05) Huston, Lila A.; Gonzales, Lauren A.; Handler, Emma; Menegaz, Rachel A.; Millar, J. CameronOsteogenesis imperfecta (OI), a developmental disorder of type I collagen, is known to cause hearing loss in ~ 60% of the diseased population. Identified forms include conductive hearing loss (17.4% of OI patients), involving loss of function within the ossicular chain, and sensorineural hearing loss (25.8%), resulting from damage to the cochlea, with the most predominant form being mixed hearing loss (56.8%), involving damage to both the cochlea and ossicles. While OI-related pathologies have largely focused on the middle ear, the pathological appearance of the cochlea (the organ most often compromised in OI-related hearing loss) has gained little focus. In this study, we examine OI-related pathologies on the cochlea in a mouse model for the severe type III OI, to document 1) the morphological differences in the inner ear for adult wildtype mice compared to OI mice in order to determine the anatomy of the diseased state, and 2) intraindividual variation between cochlea of WT and OI mice to determine potential asymmetry in the etiology of the inner ear. We hypothesize that cochlea in mice with OI will have less consistent morphology overall than their WT counterparts due to abnormal growth of the bony capsule. 4 week and 16 week old OIM mice (B6C3Fe a/a-Col1a2oim/J) (n=25) were compared to unaffected wildtype (WT) littermates (n=29) with no known hearing defects. High-resolution micro-CT scans were created for all specimens and 3D models and volumes of the cochlea were generated using 3D Slicer software. Two-tailed Mann-Whitney U-tests were used to investigate differences between 1) right and left ears of the same mouse to examine intraindividual symmetry and 2) differences in volumes between WT and OI cochlea. No major morphologic differences between OI and WT were observed, except for minor areas of higher ossification at the base of the cochlea, mostly within the OI sample. Within WT specimens, we observed little intraindividual difference in the cochlear volume (0-3%). Within OI specimens, significant differences were observed in cochlear volume between right and left ears in the same animal, indicating potential unilateral effects (Mann-Whitney U, p<0.05). When average WT and OI volumes were compared, there was much overlap between the two samples although the OI volumes had a significantly larger range than the WT range (Mann-Whitney U, p=0.704 (w16), p=0.703 (w4)). Overall, our results indicate that mice with OI are much more likely to have evidence of unilateral cochlear volume losses, despite very little difference in overall shape appearance, possibly due to bony capsule encroachment. This find indicates an extremely high potential for sensorineural and mixed hearing loss in OI-bred mice and elucidates at least one mechanism behind how this type of hearing loss might be occurring. Little is known about the pathological appearance of the cochlea in OI, leading to difficulty in managing hearing loss. Further investigation of the etiology and progression of cochlear pathologies will allow for better outcomes in hearing for those patients afflicted with OI-related hearing loss.Item The Effect of Diet on Craniofacial Growth in Osteogenesis Imperfecta Mouse Model(2018-05) Ladd, Summer H.; Menegaz, Rachel A.; Maddux, Scott D.; Reeves, Rustin E.; Borejdo, JulianOsteogenesis imperfecta (OI, or "brittle bone disease") is a rare disorder that is caused by genetic point mutations (COL1A1/COL1A2) that affect type 1 collagen. In OI type III (severe) patients, limb bones are more susceptible to skeletal fractures and the bones of the craniofacial region are underdeveloped. Some OI type III patients also suffer from dental malocclusions or fractures (dentinogenesis imperfecta, DI). The goals of this project are 1) to describe the facial phenotype in an OI mouse model, to see if this model can be used to test potential behavioral and pharmaceutical interventions; and 2) to determine if diet and masticatory loading affect the development of the craniofacial region in the OI model. The homozygous OI murine (OIM-/-), a mouse strain with a nonlethal recessively inherited mutation of the COL1A2 gene, is a potential model for the human OI type III. OIM-/- and wild type (WT) littermates were raised from weaning (21 days) to adulthood (16 weeks). Digital 3D craniofacial landmarks were taken from in-vivo micro CT scans, and Kuskal-Wallis ANOVAs, along with Mann-Whitney tests, were used to compare centroid size and interlandmark distances among treatment groups. This practicum focuses on the Week 10 mice, with 3 treatment groups: OIMxM, WTxM, and WTxP. We acknowledge that the sample is incomplete due to factors beyond our immediate control, such as OIM-/- survivability. Adolescent OIM-/- mice (week 10) were found to have on average smaller cranial and mandibular centroid sizes compared to WT mice regardless of diet. Week 10 OIM-/- mice also show several morphological similarities to the OI type III human phenotype, such as shortened cranial vault height, shortened jaw length, and altered dental spacing secondary to a shortened tooth row. We conclude that the OIM mouse model shows potential for future investigations of the growth mechanisms underlying the craniofacial presentation of OI. Furthermore, preliminary results suggest that masticatory loading during the early growth period can be used to stimulate craniofacial bone growth and improve bone quality in the OIM mouse model. Future studies will continue to improve sample size by treatment and age groups. The significance of this project is that it will give a better understanding of the role of type 1 collagen and the biomechanical mechanics of craniofacial development, which are important in the search for a new treatment method in OI.