Cancer cells: Stemness shaped by curvature

Mechanobiology of cancer cell responsiveness to chemotherapy and immunotherapy: Mechanistic insights and biomaterial platforms

Mechanical forces are central to how cancer treatments such as chemotherapeutics and immunotherapies interact with cells and tissues. At the simplest level, electrostatic forces underlie the binding events that are critical to therapeutic function. However, a growing body of literature points to mechanical factors that also affect whether a drug or an immune cell can reach a target, and to interactions between a cell and its environment affecting therapeutic efficacy. These factors affect cell processes ranging from cytoskeletal and extracellular matrix remodeling to transduction of signals by the nucleus to metastasis of cells. This review presents and critiques the state of the art of our understanding of how mechanobiology impacts drug and immunotherapy resistance and responsiveness, and of the in vitro systems that have been of value in the discovery of these effects.

Interfacial Curvature as a Potential Index for Prognosis of Colon Adenocarcinoma

Tumor invasion and metastasis are complex interfacial mechanical processes between the tumor and its surrounding tissue, with the interfacial curvature of tumor playing an important role in cancer progression. In this study, the potential role of interfacial curvature in the prognosis of patients with colon adenocarcinoma is investigated. The front edge interfacial curvature of adenocarcinoma from biopsies of patients in different tumor, lymph node, and metastasis (TNM) stages are calculated and compared, and prognosis assessment is conducted using Kaplan-Meier and Cox proportional hazards regression analyses. Results reveal that patients with larger interfacial curvature of adenocarcinoma are more likely to belong to higher TNM stages. Concomitantly, in the same TNM stage, patients with increased adenocarcinoma interfacial curvature show worse prognosis with higher recurrence and lower survival rates. Besides, interfacial curvature is an independent prognostic factor for cause-specific survival and relapse-free survival among all selected patients. Mechanical models of colon adenocarcinoma invasion and metastasis are established to better understand the close association between interfacial curvature and tumor progression. The results together with hematoxylin and eosin staining indicate that metastasis in stages T3N0M0 and T3N1M0 may be linked to large interfacial curvatures. Therefore, interfacial curvature may serve as a potential index for predicting prognosis in patients with colon adenocarcinoma.

Topographical Features of Graphene-Oxide-Functionalized Substrates Modulate Cancer and Healthy Cell Adhesion Based on the Cell Tissue of Origin

Graphene-derived materials, such as graphene oxide (GO), have been widely explored for biomedical and biological applications, including cancer research. Despite some recent works proving that GO inhibits the migration and invasion of different cancer cells, so far most of these in vitro studies have been conducted using GO sheets dispersed in solution or as a planar film. On the contrary, little is known about cellular activities, such as cell viability, adhesion, and spreading, when cancer cells interface with GO functionalized hydrogel-based surfaces, biomechanically and structurally more similar to the tumor environment. Here, we evaluate the interactions of human breast cancer cells (MDA-MB-231) with alginate (Alg)/GO hydrogel-based substrates, and compare them with a cancer cell line from human osteosarcoma (HOS) and healthy murine fibroblasts (3T3). We observed that GO addition selectively inhibits malignant breast cancer cell adhesion efficiency and spreading area, while promotes HOS and 3T3 adhesive processes. Furthermore, we did not observe the same results over Alg substrates with GO nanosheets dispersed in the medium, without embedment into the Alg. This suggests that cancer (MDA-MB-231 and HOS) and healthy (3T3) cell adhesion efficacy does not depend on the cellular tumoral nature and it is driven by the topographical cues provided by the GO-based substrates, whose physical-mechanical characteristics better mimic those of the cell native tissue. We envision that this study can provide a rational for future design and use of graphene-based nanomaterials for cancer research by deepening the knowledge of graphene-cancer cell specific interactions.