Prognostic significance of the expression levels of T‑cell immunoglobulin mucin‑3 and its ligand galectin‑9 for relapse‑free survival in triple‑negative breast cancer

Galectin-9 in cancer therapy: from immune checkpoint ligand to promising therapeutic target

Galectin-9 (Gal-9) is a vital member of the galectin family, functioning as a multi-subtype galactose lectin with diverse biological roles. Recent research has revealed that Gal-9's interaction with tumors is an independent factor that influences tumor progression. Furthermore, Gal-9 in the immune microenvironment cross-talks with tumor-associated immune cells, informing the clarification of Gal-9's identity as an immune checkpoint. A thorough investigation into Gal-9's role in various cancer types and its interaction with the immune microenvironment could yield novel strategies for subsequent targeted immunotherapy. This review focuses on the latest advances in understanding the direct and indirect cross-talk between Gal-9 and hematologic malignancies, in addition to solid tumors. In addition, we discuss the prospects of Gal-9 in tumor immunotherapy, including its cross-talk with the ligand TIM-3 and its potential in immune-combination therapy.

Killer instincts: natural killer cells as multifactorial cancer immunotherapy

Natural killer (NK) cells integrate heterogeneous signals for activation and inhibition using germline-encoded receptors. These receptors are stochastically co-expressed, and their concurrent engagement and signaling can adjust the sensitivity of individual cells to putative targets. Against cancers, which mutate and evolve under therapeutic and immunologic pressure, the diversity for recognition provided by NK cells may be key to comprehensive cancer control. NK cells are already being trialled as adoptive cell therapy and targets for immunotherapeutic agents. However, strategies to leverage their naturally occurring diversity and agility have not yet been developed. In this review, we discuss the receptors and signaling pathways through which signals for activation or inhibition are generated in NK cells, focusing on their roles in cancer and potential as targets for immunotherapies. Finally, we consider the impacts of receptor co-expression and the potential to engage multiple pathways of NK cell reactivity to maximize the scope and strength of antitumor activities.

Pattern Analysis of Serum Galectins-1, -3, and -9 in Breast Cancer

Galectins have been shown to have roles in cancer progression via their contributions to angiogenesis, metastasis, cell division, and the evasion of immune destruction. This study analyzes galectin-1, -3, and -9 serum concentrations in breast cancer patients through enzyme-linked immunosorbent assay (ELISA) against the characteristics of the patient and the tumor such as stage, molecular subtype, and receptor expression. Galectin-9 was found to be statistically significantly increased in HER2-enriched tumors and reduced in patients with hormone-receptor-positive tumors. Galectin-1 was found to be statistically significantly increased in the serum of patients who had undergone hormonal, immunotherapy, or chemotherapy. These findings provide insight into the changes in galectin levels during the progress of cancer, the response to treatment, and the molecular phenotype. These findings are valuable in the further understanding of the relationships between galectin and tumor biology and can inform future research on therapeutic targets for galectin inhibitors and the utility of galectin biomarkers.

Soluble TIM-3 as a biomarker of progression and therapeutic response in cancers and other of human diseases

Immune checkpoints inhibition is a privileged approach to combat cancers and other human diseases. The TIM-3 (T cell immunoglobulin and mucin-domain containing-3) inhibitory checkpoint expressed on different types of immune cells is actively investigated as an anticancer target, with a dozen of monoclonal antibodies in (pre)clinical development. A soluble form sTIM-3 can be found in the plasma of patients with cancer and other diseases. This active circulating protein originates from the proteolytic cleavage by two ADAM metalloproteases of the membrane receptor shared by tumor and non-tumor cells, and extracellular vesicles. In most cancers but not all, overexpression of mTIM-3 at the cell surface leads to high level of sTIM-3. Similarly, elevated levels of sTIM-3 have been reported in chronic autoimmune diseases, inflammatory gastro-intestinal diseases, certain viral and parasitic diseases, but also in cases of organ transplantation and in pregnancy-related pathologies. We have analyzed the origin of sTIM-3, its methods of dosage in blood or plasma, its presence in multiple diseases and its potential role as a biomarker to follow disease progression and/or the treatment response. In contrast to sPD-L1 generated by different classes of proteases and by alternative splicing, sTIM-3 is uniquely produced upon ADAM-dependent shedding, providing a more homogenous molecular entity and a possibly more reliable molecular marker. However, the biological functionality of sTIM-3 remains insufficiently characterized. The review shed light on pathologies associated with an altered expression of sTIM-3 in human plasma and the possibility to use sTIM-3 as a diagnostic or therapeutic marker.

TIM-3 Is a Potential Immune Checkpoint Target in Cats with Mammary Carcinoma

Recent findings in human breast cancer (HBC) indicate that T-cell immunoglobulin and mucin-domain-containing molecule-3 (TIM-3)-targeted therapies may effectively activate anticancer immune responses. Although feline mammary carcinoma (FMC) is a valuable cancer model, no studies on TIM-3 have been developed in this species. Thus, we evaluated the expression of TIM-3 by immunohistochemistry in total (t), stromal (s), and intra-tumoral (i) tumor-infiltrating lymphocytes (TILs) and in cancer cells, of 48 cats with mammary carcinoma. In parallel, serum TIM-3 levels were quantified using ELISA and the presence of somatic mutations in the TIM-3 gene was evaluated in 19 tumor samples. sTILs-TIM3+ were more frequent than iTILs-TIM-3+, with the TIM-3 ex-pression in sTILs and cancer cells being associated with more aggressive clinicopathological features. In contrast, the TIM-3 expression in iTILs and tTILs was associated with a more benign clinical course. Moreover, the serum TIM-3 levels were lower in animals with FMC when compared to healthy animals (p < 0.001). Only one somatic mutation was found in the TIM-3 gene, at intron 2, in one tumor sample. Altogether, our results suggest that the expression of TIM-3 among TILs subpopulations and cancer cells may influence the clinical outcome of cats with FMC, in line with the previous reports in HBC.