RESUMO
We investigated the role of PI3Kγ in oral carcinogenesis by using a murine model of oral squamous carcinoma generated by exposure to 4-nitroquinoline 1-oxide (4NQO) and the continuous human cancer cell line HSC-2 and Cal-27. PI3Kγ knockout (not expressing PI3Kγ), PI3Kγ kinase-dead (carrying a mutation in the PI3Kγ gene causing loss of kinase activity) and wild-type (WT) C57Bl/6 mice were administered 4NQO via drinking water to induce oral carcinomas. At sacrifice, lesions were histologically examined and stained for prognostic tumoral markers (EGFR, Neu, cKit, Ki67) and inflammatory infiltrate (CD3, CD4, CD8, CD19 and CD68). Prevalence and incidence of preneoplastic and exophytic lesions were significantly and similarly delayed in both transgenic mice versus the control. The expression of prognostic markers, as well as CD19+ and CD68+ cells, was higher in WT, while T lymphocytes were more abundant in tongues isolated from transgenic mice. HSC-2 and Cal-27 cells were cultured in the presence of the specific PI3Kγ-inhibitor (IPI-549) which significantly impaired cell vitality in a dose-dependent manner, as shown by the MTT test. Here, we highlighted two different mechanisms, namely the modulation of the tumor-infiltrating cells and the direct inhibition of cancer-cell proliferation, which might impair oral cancerogenesis in the absence/inhibition of PI3Kγ.
RESUMO
Adult stem cells reside in body tissues to preserve organs and whole organism homeostasis. They are acquiring a prominent role in the contemporary medicine. Many protocols to isolate and cultivate adult stem cells have been so far described, though they are often lengthy, laborious, and require very expansive instruments, materials, and reagents. On this basis, we describe a simple, cheap but at the same time functional method to: (1) isolate dental pulp stem cells (DPSC), (2) expand and cultivate DPSC, (3) cryopreserve DPSC, (4) characterize DPSC, and (5) differentiate DPSC into both mesenchymal and non-mesenchymal lineages.
