Preheat the oven to 180°C (350°F) and grease a baking dish.
Cook the pasta according to package instructions until al dente. Drain and set aside.
In a separate bowl, combine the tuna, marinara sauce, dried oregano, garlic powder, salt, and pepper.
In the greased baking dish, layer half of the cooked pasta. Top with half of the tuna mixture, followed by half of the cheddar and mozzarella cheeses.
Repeat the layers with the remaining pasta, tuna mixture, and cheeses.
In a small bowl, mix the breadcrumbs with olive oil until well combined. Sprinkle the breadcrumb mixture evenly over the top layer of cheese.
Bake in the preheated oven for 25-30 minutes, or until the cheese is melted and bubbly and the breadcrumbs are golden brown.
Remove from the oven and let it cool for a few minutes before serving.