Decreased tumor size <i>in vivo</i> is achieved by depletion of miR-21 <i>in vitro</i>.

<p>A375 cells were transfected <i>in vitro</i> with an LNA oligonucleotide targeting miR-21 or a control LNA oligonucleotide. Cells were collected 24 hours post‑transfection for total RNA isolation. The RNA was converted to cDNA, and Real‑Time PCR for miR-21 confirmed reduced miR-21 expression (<b>A</b>). Transfected cells were then injected subcutaneously into athymic nude mice, and tumor growth was followed. Tumor volume was calculated as V = L × l² × 0.5, where L and l represent the larger and the smaller tumor diameter, respectively. Mean tumor volumes are represented (<b>B</b>). At the completion of the study, tumors were harvested, fixed and embedded, and evaluated for TIMP3 protein by immunohistochemistry, where TIMP3 immunoreactivity is in brown (<b>C</b>). N = 4 for control LNA tumors and n = 6 for anti‑miR‑21 LNA tumors. Error bars represent standard error. * p < 0.05.