52 A new study has revealed that a specific gene, GPR65, plays a pivotal role in the progression of gliomas, a type of brain tumour. The research, published in the journal Neurosurgical Review, provides fresh insights into how the tumour’s microenvironment, particularly macrophages, contributes to its resistance to treatment. Gliomas are notorious for being one of the most challenging forms of cancer to treat. Among them, glioblastomas are the most aggressive, with patients facing poor prognoses due to the tumour’s ability to invade surrounding brain tissue and resist therapies. This resistance has largely been attributed to the complex interactions between tumour cells and the non-cancerous cells that surround them, including immune cells known as macrophages. These macrophages, which infiltrate glioma tissues and make up close to 50% of the cells in some tumors, were the subject of the study, which was under the direction of a group of researchers from Tianjin Medical University. Specifically, they investigated the role of GPR65, a gene that appears to be central to the behaviour of these macrophages. The researchers discovered that GPR65 is highly expressed in the tumour’s immune cells rather than the tumour cells themselves. These immune cells, also referred to as M2-like macrophages, are associated with an immunosuppressive environment that guards the tumor from the body’s own immune system attacking it. By fostering this protective environment, GPR65 contributes to the tumour’s progression and resistance to treatment. The team found that GPR65 is a key gene in the macrophage-related module in gliomas by using a number of advanced genetic analyses. This means that the gene is integral to how these macrophages function within the tumour. Higher levels of GPR65 were found to correlate with more aggressive tumour behaviour, which in turn was linked to worse patient outcomes. The study also revealed that the gene is particularly active in areas of the tumour with increased blood vessel formation, a region where these macrophages are most prevalent. This suggests that GPR65 not only helps protect the tumour from immune attack but also supports its growth by promoting the formation of new blood vessels. Crucially, the researchers found that when GPR65 was inhibited, the immune cells’ ability to respond to the tumour was significantly diminished. This resulted in a reduction in the growth rate of the tumour cells. This finding could open the door to new therapeutic approaches aimed at disrupting the tumour’s support system rather than targeting the cancer cells directly. By inhibiting GPR65, it may be possible to break “malignant cooperation” between glioma cells and the surrounding immune cells, providing a new avenue for treatment. The research underscores the potential for targeting the tumour microenvironment in addition to the cancer cells themselves. This study adds to the growing body of research that highlights the importance of understanding the tumour microenvironment in cancer treatment. While traditional therapies have focused on killing cancer cells, it is becoming increasingly clear that the cells surrounding the tumour are just as important in determining whether a treatment will be successful. The Tianjin Medical University team hopes that their findings will inspire further research into how GPR65 and other genes involved in the immune response can be targeted to improve outcomes for patients with gliomas, particularly those with aggressive glioblastomas. As treatments evolve, the ability to manipulate the tumour’s microenvironment could become a crucial weapon in the fight against this devastating disease.