3D collagen type I matrix inhibits the antimigratory effect of doxorubicin

<p>Abstract</p> <p>Background</p> <p>The cell microenvironment, especially extracellular matrix proteins, plays an important role in tumor cell response to chemotherapeutic drugs. The present study was designed to investigate whether this microenvironment can influence the antimigratory effect of an anthracycline drug, doxorubicin, when tumor cells are grown in a matrix of type I collagen, a three-dimensional (3D) context which simulates a natural microenvironment.</p> <p>Methods</p> <p>To this purpose, we studied the migratory parameters, the integrin expression, and the activation state of focal adhesion kinase (FAK) and GTPase RhoA involved in the formation of focal adhesions and cell movement. These parameters were evaluated at non toxic concentrations which did not affect HT1080 cell proliferation.</p> <p>Results</p> <p>We show that while doxorubicin decreased cell migration properties by 70% in conventional two-dimensional (2D) culture, this effect was completely abolished in a 3D one. Regarding the impact of doxorubicin on the focal adhesion complexes, unlike in 2D systems, the data indicated that the drug neither affected β1 integrin expression nor the state of phosphorylation of FAK and RhoA.</p> <p>Conclusion</p> <p>This study suggests the lack of antiinvasive effect of doxorubicin in a 3D environment which is generally considered to better mimic the phenotypic behaviour of cells <it>in vivo</it>. Consistent with the previously shown resistance to the cytotoxic effect in a 3D context, our results highlight the importance of the matrix configuration on the tumor cell response to antiinvasive drugs.</p

Integrated approach to characterize the impact of aging on the structural organization and mechanical properties of type I collagen

Le collagène de type I est la composante majeure de la matrice extracellulaire dans l’organisme. Son organisation architecturale et structurale joue un rôle important dans les propriétés mécaniques de nombreux tissus et dans le phénotype cellulaire au niveau physiologique et pathologique. L’objectif de ce travail est de développer une approche intégrée pour caractériser l'impact du vieillissement chronologique sur l’organisation structurale et les propriétés mécaniques du collagène de type I. La première partie concerne la caractérisation des altérations dans l’organisation structurale et morphologique de faisceaux de fibres de collagène de type I en utilisant la spectroscopie Raman polarisée et la microscopie de génération de seconde harmonique. Les données obtenues montrent que les bandes Raman de la proline et de l’hydroxyproline, ainsi que la bande amide I et III sont sensibles à la polarisation et à l'âge. Nous avons ensuite couplé un spectromètre Raman portable avec un banc de tests mécaniques afin de suivre en temps réel l’évolution de l’emprunte spectrale Raman du faisceau de fibres de collagène type I durant l’application des contraintes mécaniques. L’analyse des données montre une augmentation du module de Young, de la tension limite d’élasticité et de la charge maximale de rupture au cours du vieillissement. Au niveau moléculaire, la spectroscopie Raman a permis d’identifier des liaisons au sein du collagène de type I qui sont affectées par le stress mécanique d’une manière différentielle au cours du vieillissement.Type I collagen is the major component of the extracellular matrix. Its architectural and structural organization plays an important role in the mechanical properties of many tissues and cell phenotype at the physiological and pathological levels. The objective of this work is to develop an integrated approach to bring a new insight on the impact of chronological aging on the structural organization and mechanical properties of type I collagen. The first part of the study aimed the characterization of changes in the structural and morphological organization of type I collagen fiber fascicles using polarized Raman spectroscopy and second harmonic generation microscopy. Data showed that the Raman bands of proline and hydroxyproline, as well as the amide I and III bands were sensitive to polarization and age. We then combined a portable Raman spectrometer with a mechanical tensile testing device in order to monitor in real time the changes in the Raman fingerprint of type I collagen fibers during the mechanical stress. Data showed an increase in Young's modulus, yield strength and ultimate tensile strength with aging. At the molecular level, Raman spectroscopy allowed to identify bonds within type I collagen that were affected by mechanical stress in a differential manner with aging

First plasma and tissue pharmacokinetic study of the YSNSG cyclopeptide, a new integrin antagonist, using microdialysis

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Age-related modifications of type I collagen impair DDR1-induced apoptosis in non-invasive breast carcinoma cells

Type I collagen and DDR1 axis has been described to decrease cell proliferation and to initiate apoptosis in non-invasive breast carcinoma in three-dimensional cell culture matrices. Moreover, MT1-MMP down-regulates these effects. Here, we address the effect of type I collagen aging and MT1-MMP expression on cell proliferation suppression and induced-apoptosis in non-invasive MCF-7 and ZR-75-1 breast carcinoma. We provide evidence for a decrease in cell growth and an increase in apoptosis in the presence of adult collagen when compared to old collagen. This effect involves a differential activation of DDR1, as evidenced by a higher DDR1 phosphorylation level in adult collagen. In adult collagen, inhibition of DDR1 expression and kinase function induced an increase in cell growth to a level similar to that observed in old collagen. The impact of aging on the sensitivity of collagen to MT1-MMP has been reported recently. We used the MT1-MMP expression strategy to verify whether, by degrading adult type I collagen, it could lead to the same phenotype observed in old collagen 3D matrix. MT1-MMP overexpression abrogated the proliferation suppression and induced-apoptosis effects only in the presence of adult collagen. This suggests that differential collagen degradation by MT1-MMP induced a structural disorganization of adult collagen and inhibits DDR1 activation. This could in turn impair DDR1-induced cell growth suppression and apoptosis. Taken together, our data suggest that modifications of collagen structural organization, due to aging, contribute to the loss of the growth suppression and induced apoptosis effect of collagen in luminal breast carcinoma. MT1-MMP-dependent degradation and aging of collagen have no additive effects on these processes

Collagen type 1 promotes survival of human breast cancer cells by overexpressing Kv10.1 potassium and Orai1 calcium channels through DDR1-dependent pathway

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Original association of ion transporters mediates the ECM-induced breast cancer cell survival: Kv10.1-Orai1-SPCA2 partnership

Abstract In the last years it has been shown that many components of tumor microenvironment (TM) can induce cell signaling that permit to breast cancer cells (BC) to maintain their aggressiveness. Ion channels have a role in mediating TM signal; recently we have demonstrated a functional collaboration between Kv10.1 and Orai1 channels in mediating the pro-survival effect of collagen 1 on BC cells. Here we show how SPCA2 (Secretory Pathway Ca2+ ATPase) has a role in this process and is able to support survival and proliferation induced by collagen 1. By participating to an auto-sustaining loop, SPCA2 enhances membrane expression of Kv10.1 and Orai1; the activity of every component of this trio is necessary to mediate a store independent calcium entry (SICE). This SICE is fundamental to maintain both the activation of the pro-survival pathway and the membrane localization and consequently the activity of the two channels. Moreover, the three proteins and the collagen receptor DDR1 are overexpressed only in aggressive tumors tissues. In this work, we propose a novel association between SPCA2, Kv10.1 and Orai1 involved in mediating transduction signals from TM to the BC cells that can be potentially exploited in the search of novel therapeutic targets specific to tumor tissues

Hybrid Mineral/Organic Material Induces Bone Bridging and Bone Volume Augmentation in Rat Calvarial Critical Size Defects

International audienceIn craniofacial bone defects, the promotion of bone volume augmentation remains a challenge. Finding strategies for bone regeneration such as combining resorbable minerals with organic polymers would contribute to solving the bone volume roadblock. Here, dicalcium phosphate dihydrate, chitosan and hyaluronic acid were used to functionalize a bone-side collagen membrane. Despite an increase in the release of inflammatory mediators by human circulating monocytes, the in vivo implantation of the functionalized membrane allowed the repair of a critical-sized defect in a calvaria rat model with de novo bone exhibiting physiological matrix composition and structural organization. Microtomography, histological and Raman analysis combined with nanoindentation testing revealed an increase in bone volume in the presence of the functionalized membrane and the formation of woven bone after eight weeks of implantation; these data showed the potential of dicalcium phosphate dihydrate, chitosan and hyaluronic acid to induce an efficient repair of critical-sized bone defects and establish the importance of thorough multi-scale characterization in assessing biomaterial outcomes in animal models