Revati Sharma

Mitochondrial-associated granulocyte macrophage colony-stimulating factor (Magmas) is a unique protein located in the inner membrane of mitochondria, with an active role in scavenging reactive oxygen species (ROS) in cellular systems. Ovarian cancer (OC), one of the deadliest gynaecological cancers, is characterised by genomic instability, affected by ROS production in the tumour microenvironment. This manuscript discusses the role of Magmas and efficacy of its novel small molecule inhibitor BT#9 in OC progression, metastasis, and chemoresistance. Magmas expression levels were significantly elevated in high-grade human OC compared to benign tumours by immunohistochemistry. The inhibition of Magmas by BT#9 enhanced ROS production and reduced mitochondrial membrane permeability, basal respiration, mitochondrial ATP production, and cellular functions, such as the proliferation and migration of OC cell lines in vitro. Oral administration of BT#9 in vivo significantly reduced tumour growth and spread and enhanced the survival of mice without having any effect on the peritoneal organs. These data suggest that Magmas is functionally important for OC growth and spread by affecting ROS levels and that the inhibition of Magmas activity by BT#9 may provide novel clinical benefits for patients with this malignancy.

Pregnancy associated plasma protein-A (PAPP-A) plays an integral role in breast cancer (BC), especially triple negative breast cancer (TNBC). This subtype accounts for the most aggressive BC, possesses high tumor heterogeneity, is least responsive to standard treatments and has the poorest clinical outcomes. There is a critical need to address the lack of effective targeted therapeutic options available. PAPP-A is a protein that is highly elevated during pregnancy. Frequently, higher PAPP-A expression is detected in tumors than in healthy tissues. The increase in expression coincides with increased rates of aggressive cancers. In BC, PAPP-A has been demonstrated to play a role in tumor initiation, progression, metastasis including epithelial-mesenchymal transition (EMT), as well as acting as a biomarker for predicting patient outcomes. In this review, we present the role of PAPP-A, with specific focus on TNBC. The structure and function of PAPP-A, belonging to the pappalysin subfamily, and its proteolytic activity are assessed. We highlight the link of BC and PAPP-A with respect to the IGFBP/IGF axis, EMT, the window of susceptibility and the impact of pregnancy. Importantly, the relevance of PAPP-A as a TNBC clinical marker is reviewed and its influence on immune-related pathways are explored. The relationship and mechanisms involving PAPP-A reveal the potential for more treatment options that can lead to successful immunotherapeutic targets and the ability to assist with better predicting clinical outcomes in TNBC.

Cholangiocarcinoma (CCA) is a hepatobiliary malignancy associated with steadily increasing incidence and poor prognosis. Ongoing clinical trials are assessing the effectiveness and safety of a few immune checkpoint inhibitors (ICIs) in CCA patients. However, these ICI treatments as monotherapies may be effective for a proportion of patients with CCA. The prevalence and distribution of other immune checkpoints (ICs) in CCA remain unclear. In this pilot study, we screened databases of CCA patients for the expression of 19 ICs and assessed the prognostic significance of these ICs in CCA patients. Notably, expression of immune modulator IDO1 and PD-L1 were linked with poor overall survival, while FASLG and NT5E were related to both worse overall survival and progression-free survival. We also identified immune modulators IDO1, FASLG, CD80, HAVCR2, NT5E, CTLA-4, LGALS9, VTCN1 and TNFRSF14 that synergized with PD-L1 and correlated with worse patient outcomes. In vitro studies revealed that the expression of ICs was closely linked with aggressive CCA subpopulations, such as cancer stem cells and cells undergoing TGF-β and TNF-α-mediated epithelial-to-mesenchymal transition. These findings suggest that the aforementioned IC molecules may serve as potential prognostic biomarkers and drug targets in CCA patients, leading to lasting and durable treatment outcomes.