Promising Highly Targeted Therapies for Cholangiocarcinoma: A Review and Future Perspectives

When will the immune-stimulating antibody conjugates (ISACs) be transferred from bench to bedside?

Immunostimulatory antibody conjugates (ISACs) as a promising new generation of targeted therapeutic antibody-drug conjugates (ADCs), that not only activate innate immunity but also stimulate adaptive immunity, providing a dual therapeutic effect to eliminate tumor cells. However, several ISACs are still in the early stages of clinical development or have already failed. Therefore, it is crucial to design ISACs more effectively to overcome their limitations, including high toxicity, strong immunogenicity, long development time, and poor pharmacokinetics. This review aims to summarize the composition and function of ISACs, incorporating current design considerations and ongoing clinical trials. Additionally, the review delves into the current issues with ISACs and potential solutions, such as adjusting the drug-antibody ratio (DAR) to improve the bioavailability of ISACs. By leveraging the affinity and bioavailability-enhancing properties of bispecific antibodies, the utility between antibodies and immunostimulatory agents can be balanced. Commonly used immunostimulatory agents may induce systemic immune reactions, and BTK (Bruton's tyrosine kinase) inhibitors can regulate immunogenicity. Finally, the concept of grafting ADC's therapeutic principles is simple, but the combination of payload, linker, and targeted functional molecules is not a simple permutation and combination problem. The development of conjugate drugs faces more complex pharmacological and toxicological issues. Standing on the shoulders of ADC, the development and application scenarios of ISAC are endowed with broader space.

A NRF2 Regulated and the Immunosuppressive Microenvironment Reversed Nanoplatform for Cholangiocarcinoma Photodynamic-Gas Therapy

Photodynamic therapy (PDT) is a minimally invasive and controllable local cancer treatment for cholangiocarcinoma (CCA). However, the efficacy of PDT is hindered by intratumoral hypoxia and the presence of an antioxidant microenvironment. To address these limitations, combining PDT with gas therapy may be a promising strategy to enhance tumor oxygenation. Moreover, the augmentation of oxidative damage induced by PDT and gas therapy can be achieved by inhibiting NRF2, a core regulatory molecule involved in the antioxidant response. In this study, an integrated nanotherapeutic platform called CMArg@Lip, incorporating PDT and gas therapies using ROS-responsive liposomes encapsulating the photosensitizer Ce6, the NO gas-generating agent L-arginine, and the NRF2 inhibitor ML385, is successfully developed. The utilization of CMArg@Lip effectively deals with challenges posed by tumor hypoxia and antioxidant microenvironment, resulting in elevated levels of oxidative damage and subsequent induction of ferroptosis in CCA. Additionally, these findings suggest that CMArg@Lip exhibits notable immunomodulatory effects, including the promotion of immunogenic cell death and facilitation of dendritic cell maturation. Furthermore, it contributes to the anti-tumor function of cytotoxic T lymphocytes through the downregulation of PD-L1 expression in tumor cells and the activation of the STING signaling pathway in myeloid-derived suppressor cells, thereby reprogramming the immunosuppressive microenvironment via various mechanisms.

Ex vivo liver resection and auto-transplantation and special systemic therapy in perihilar cholangiocarcinoma treatment

This editorial contains comments on the article "Systematic sequential therapy for ex vivo liver resection and autotransplantation: A case report and review of literature" in the recent issue of World Journal of Gastrointestinal Surgery. It points out the actuality and importance of the article and focuses primarily on the role and place of ex vivo liver resection and autotransplantation (ELRAT) and systemic therapy, underlying molecular mechanisms for targeted therapy in perihilar cholangiocarcinoma (pCCA) management. pCCA is a tough malignancy with a high proportion of advanced disease at the time of diagnosis. The only curative option is radical surgery. Surgical excision and reconstruction become extremely complicated and not always could be performed even in localized disease. On the other hand, ELRAT takes its place among surgical options for carefully selected pCCA patients. In advanced disease, systemic therapy becomes a viable option to prolong survival. This editorial describes current possibilities in chemotherapy and reveals underlying mechanisms and projections in targeted therapy with kinase inhibitors and immunotherapy in both palliative and adjuvant settings. Fibroblast grow factor and fibroblast grow factor receptor, human epidermal growth factor receptor 2, isocitrate dehydrogenase, and protein kinase cAMP activated catalytic subunit alpha (PRKACA) and beta (PRKACB) pathways have been actively investigated in CCA in last years. Several agents were introduced and approved by the Food and Drug Administration. They all demonstrated meaningful activity in CCA patients with no global change in outcomes. That is why every successfully treated patient counts, especially those with advanced disease. In conclusion, pCCA is still hard to treat due to late diagnosis and extremely complicated surgical options. ELRAT also brings some hope, but it could be performed in very carefully selected patients. Advanced disease requires systemic anticancer treatment, which is supposed to be individualized according to the genetic and molecular features of cancer cells. Targeted therapy in combination with chemo-immunotherapy could be effective in susceptible patients.

Current and Emerging Therapeutic Targets for the Treatment of Cholangiocarcinoma: An Updated Review

Cholangiocarcinoma is a malignancy of the bile ducts that is often associated with late diagnosis, poor overall survival, and limited treatment options. The standard of care therapy for cholangiocarcinoma has been cytotoxic chemotherapy with modest improvements in overall survival with the addition of immune checkpoint inhibitors. The discovery of actionable mutations has led to the advent of targeted therapies against FGFR and IDH-1, which has expanded the treatment landscape for this patient population. Significant efforts have been made in the pre-clinical space to explore novel immunotherapeutic approaches, as well as antibody-drug conjugates. This review provides an overview of the current landscape of treatment options, as well as promising future therapeutic targets.