An overview of new therapeutic approaches for the treatment of metastatic breast cancer

Metastatic cancer is also referred to as stage- IV cancer, it is the process by which cancer cells move to different areas of the body. Metastasis is the main factor contributing to deaths from cancer. ⁽¹⁾ A novel kind of treatment for breast cancer is immunotherapy. Following the long-standing use of targeted biological therapy and endocrine therapy, new treatment options have been made possible by the discovery of immune checkpoint inhibitors and a better understanding of how cancer cells evade the immune system. Because most breast cancers have a limited number of lymphocytes that infiltrate the tumour, single-drug treatments using monoclonal antibodies against programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) have not demonstrated much success in treating patients with metastatic breast cancer. The development of immunotherapy and molecularly targeted treatment combinations for metastatic breast cancer is gaining attention. ⁽²⁾

In this Personal View, we examine the information that is currently available and the ongoing research being done to determine the safety and effectiveness of immunotherapeutic approaches when used in conjunction with chemotherapy, radiotherapy, angiogenesis inhibitors, inhibitors of cyclin-dependent kinases 4 and 6, HER2-targeted therapy, poly(ADP-ribose) polymerase inhibitors, and other treatments.⁽²⁾ Gene therapy has been hailed as a new scientific revolution since it offers the advantage of treating diseases at the genetic level. However, the therapeutic efficacy is severely compromised by the extracellular and intracellular hurdles that occur during gene transport, such as enzymatic degradation and endo-/lysosomal sequestration. The translocation of internalized molecules into the cytosol through photochemical internalization (PCI) has emerged as a promising method for inducing endo-/lysosomal leakage; nevertheless, the effect of PCI is currently inadequate because of the shallow light penetration depth. ⁽³⁾ A novel kind of treatment for breast cancer is immunotherapy. Following the long-standing use of targeted biological therapy and endocrine therapy, new treatment options have been made possible by the discovery of immune checkpoint inhibitors and a better understanding of how cancer cells evade the immune system. Because most breast cancers have a limited number of lymphocytes that infiltrate the tumor, single-drug treatments using monoclonal antibodies against programmed death-1 (PD-1) In the world of biomedicine, gene therapy has been heralded as the next great revolution. However, the therapeutic efficacy is severely compromised by the extracellular and intracellular hurdles that occur during gene transport, such as enzymatic degradation and endo-/lysosomal sequestration. The translocation of internalised molecules into the cytosol through photochemical internalisation (PCI) has emerged as a promising method for inducing endo-/lysosomal leakage; nevertheless, the effect of PCI is currently inadequate because of the shallow light penetration depth. Here, we use ROS produced by in situ cascaded catalytic events in tumours using Mn ²? -mediated Fenton-like reaction and GOx-mediated redox reaction to establish tumour microenvironment-specific improved gene delivery. Cargo gene complexes have showed effective enzymatic protection and successful endo-/lysosomal escape. ⁽²⁾

Combination of immunotherapy and targeted therapy for breast cancer:

The development of immunotherapy and molecularly targeted treatment combinations for metastatic breast cancer is gaining attention. In this Personal View, we examine the information that is currently available and the ongoing research being done to determine the safety and effectiveness of immunotherapeutic approaches when used in conjunction with chemotherapy, radiotherapy, angiogenesis inhibitors, inhibitors of cyclin dependent kinases 4 and 6, HER2- targeted therapy, poly (ADP-ribose) polymerase inhibitors, and other treatments. ⁽²⁾

Gene Therapy:

In the world of biomedicine, gene therapy has been heralded as the next great revolution. However, the therapeutic efficacy is severely compromised by the extracellular and intracellular hurdles that occur during gene transport, such as enzymatic degradation and endo-/lysosomal sequestration. The translocation of internalised molecules into the cytosol through photochemical internalisation (PCI) has emerged as a promising method for inducing endo-/lysosomal leakage; nevertheless, the effect of PCI is currently inadequate because of the shallow light penetration depth. Here, we use ROS produced by in situ cascaded catalytic events in tumours using Mn ²? -mediated Fenton-like reaction and GOx-mediated redox reaction to establish tumour microenvironment-specific improved gene delivery. Cargo gene complexes have showed effective enzymatic protection and successful endo-/lysosomal escape. ⁽³⁾