ACOT11 suppresses prostate cancer progression by inhibiting mitochondrial homeostasis and the PI3K/AKT signaling pathway

Prostate cancer is a common disease among older men, and while it can often be managed in its early stages, it has a stubborn tendency to evolve. Within a few years, many cases transform into a more aggressive form known as castration-resistant prostate cancer, which is difficult to treat and spreads quickly. To understand why this happens, scientists look closely at the tiny power plants inside our cells, called mitochondria, and the way cells manage their internal fats. These power plants provide the energy cells need to survive and grow, but when they malfunction, they can sometimes fuel the rapid expansion of tumors. Similarly, the way a cell handles its fat molecules is crucial; if this balance is disturbed, it can trigger a chain reaction that helps cancer cells multiply and spread. Researchers have long suspected that specific enzymes, which act like chemical scissors to cut fat molecules, play a hidden role in this process, but their exact function in prostate cancer has remained a mystery.

A team of researchers from hospitals in Hebei province set out to solve this puzzle by studying a specific enzyme called ACOT11. This enzyme is known to help break down long-chain fats, a process essential for keeping cellular energy and structure in check. The scientists began by comparing tissue samples from twenty men with prostate cancer against twenty men with a benign, non-cancerous condition. They found a clear pattern: the cancerous tissues contained significantly lower levels of ACOT11 than the healthy ones. This discovery suggested that the loss of this enzyme might be a key step in the development of the disease. To test this idea further, the team turned to laboratory cultures of prostate cancer cells. They created two scenarios: one where they artificially lowered the amount of ACOT11 in the cells, and another where they forced the cells to produce extra amounts of it.

The results were striking and pointed in opposite directions. When the researchers reduced ACOT11, the cancer cells became more aggressive. They grew faster, moved more easily across the culture dish, and showed a stronger ability to invade through barriers, mimicking how cancer spreads in the body. Conversely, when they increased the levels of ACOT11, the cancer cells slowed down. Their growth rate dropped, their ability to migrate diminished, and they began to die off in a controlled manner known as apoptosis. This confirmed that ACOT11 acts as a natural brake on the cancer, a tumor suppressor that keeps the disease in check when it is present in normal amounts.

Digging deeper into the "why," the researchers observed what was happening inside the cells' mitochondria. In the cells where ACOT11 was boosted, the mitochondria began to show signs of distress. They swelled up, their internal structures became disorganized, and they produced less energy. At the same time, the cells accumulated harmful waste products and experienced a surge in calcium levels, which are signals that often trigger cell death. The team also looked at the chemical signals that tell cells to grow, specifically a pathway known as PI3K/AKT. In healthy cells, this pathway is tightly regulated, but in aggressive cancer, it is often stuck in the "on" position, driving uncontrolled growth. The study found that high levels of ACOT11 successfully turned down this signaling pathway, effectively cutting off the fuel supply that the cancer cells needed to thrive.

The researchers also examined the physical structure of the cells using powerful microscopes that can see details smaller than a virus. They saw that the cells with high ACOT11 levels had mitochondria that looked damaged and broken, a clear visual sign that the cell's internal machinery was failing. In contrast, the cells where ACOT11 was removed kept their mitochondria intact and functioning well, allowing them to survive and multiply. This physical evidence supported the idea that ACOT11 works by disrupting the delicate balance of the cell's power plants, forcing the cancer to shut down.

While the study was conducted entirely in the laboratory using cell cultures and tissue samples, the findings offer a new perspective on how prostate cancer progresses. The research suggests that the loss of ACOT11 is not just a side effect of the disease but a driving force that allows the cancer to become more dangerous. By understanding that this enzyme normally helps keep the cell's energy and fat metabolism in balance, scientists can now see a potential new target for treatment. If doctors could find a way to restore ACOT11 levels or mimic its effects, they might be able to stop the cancer's growth or even force it to die. However, the researchers are careful to note that these results are currently limited to the lab, and more work is needed to see if these findings hold true in living patients. For now, the study provides a clear map of a previously hidden mechanism, showing how a single enzyme can influence the fate of a cancer cell by managing its energy and internal signals.