Targeting these macrophages with the GW2580 CSF1R inhibitor leads to restored immune surveillance and improved survival. Overall, we demonstrate that circulating macrophages are responsible, at least in part, for the immune suppression in SCLL leukemia models, and targeting macrophages in this system improves the survival of leukemic mice.

Further, six drugs (Vinorelbine, GW-2580, S-Trityl-L-cysteine, BI-2536, CP466722, NSC-87877) were found to be correlated with the RiskScore. In addition, KRT19 silencing markedly inhibited the invasion and migration of OC cells. This study established a relapse-related RiskScore model based on five prognostic genes (LDHA, NOP58, NMU, KRT19, and RPS23), offering novel insights into the recurrence mechanisms in OC and contributing to the development of individualized treatment strategies.

These results suggest that [11C]FJRD is a potential CSF1R-PET tracer for more sensitive detection of CSF1R, compared to [11C]CPPC and [11C]GW2580. However, the high level off-target binding necessitates further improvements in specificity for CSF1R imaging.

Addition of cold CPPC partially blocked in - vitro [ 11 C]FJRD binding in the various organs with blocking effects from 9 to 67%, and other two CSF1R inhibitors, GW2580 and BLZ945, showed minimal blocking effect, suggesting unignorable off-target binding in these organs. Conclusions These results suggest [ 11 C]FJRD as a potential CSF1R-PET tracer for more sensitively detecting CSF1R compared to [ 11 C]CPPC and [ 11 C]GW2580. However, high-level off-target binding requires further improvement in specificity for CSF1R imaging.

In this review, we will focus on the comparison of three different pharmacological CSF-1R inhibitors (PLX3397, PLX5622, and GW2580) regarding microglial depletion. We will also highlight the promising results obtained by microglial depletion strategies in adult models of neurological disorders and argue they could also prove promising in neurodevelopmental diseases associated with microglial activation and neuroinflammation. Finally, we will discuss the lack of knowledge about the effects of these strategies on neurons, astrocytes, and oligodendrocytes in adults and during neurodevelopment.

More importantly, we found that Proguanil's inhibitory effect on U87MG cell growth and migration was positively correlated with CSF1R expression, and this effect diminished following CSF1R knockdown and Proguanil demonstrated synergistic effects with CSF1R-targeting positive drugs (BLZ945 and GW2580). Meanwhile, Proguanil targeted CSF1R to inhibit M2-type polarization of tumor-associated macrophages (TAMs) and their proliferation, thus altering the tumor microenvironment while indirectly suppressing the proliferation and migration of U87MG cells. Taken together, these findings suggest that Proguanil may serve as a promising CSF1R antagonist for GBM treatment.

MEG3 modulates the TME by affecting TAMs through CSF-1, thereby influencing the balance of Th1/Th2 cells and altering the expression of PD-1/PD-L1s. This study demonstrates that targeting MEG3 is an effective therapeutic strategy for HCC.

Treatment with JDF reduced the EMT and migratory capacity of liver cancer cells, which might be attributed to the inhibition of M2 macrophage infiltration and interruption of the CSF-1/PI3K/AKT signaling pathway. This mechanism may hold significant implications for mitigating the risk of metastatic spread in the aftermath of hepatic surgery.

P1/2; Active, not recruiting --> Completed | N=43 --> 6 | Trial completion date: Sep 2025 --> Sep 2023 | Trial primary completion date: Sep 2024 --> Sep 2023

P1/2, N=409, Terminated, Pfizer | Phase classification: P1b/2 --> P1/2

However, gating criteria for efficacy were not met for expansion beyond 80 patients in phase II and the sponsor did not continue development of the combination of spartalizumab and lacnotuzumab for oncology indications. The potential signal of activity in pancreatic cancer should be further explored.