bims-limsir Biomed News
on Lipophilic modified siRNAs
Issue of 2023–10–01
three papers selected by
Ivan V. Chernikov, Institute of Сhemical Biology and Fundamental Medicine of the SB RAS



  1. Cells. 2023 Sep 11. pii: 2253. [Epub ahead of print]12(18):
      The potential of oligonucleotide therapeutics is undeniable as more than 15 drugs have been approved to treat various diseases in the liver, central nervous system (CNS), and muscles. However, achieving effective delivery of oligonucleotide therapeutics to specific tissues still remains a major challenge, limiting their widespread use. Chemical modifications play a crucial role to overcome biological barriers to enable efficient oligonucleotide delivery to the tissues/cells of interest. They provide oligonucleotide metabolic stability and confer favourable pharmacokinetic/pharmacodynamic properties. This review focuses on the various chemical approaches implicated in mitigating the delivery problem of oligonucleotides and their limitations. It highlights the importance of linkers in designing oligonucleotide conjugates and discusses their potential role in escaping the endosomal barrier, a bottleneck in the development of oligonucleotide therapeutics.
    Keywords:  antisense oligonucleotides (ASOs); cleavable linkers; endosomal escape; endosomolytic agents; linker chemistry; non-cleavable linkers; oligonucleotide conjugates; oligonucleotide delivery; oligonucleotide therapeutics; pH-sensitive linkers; siRNA
    DOI:  https://doi.org/10.3390/cells12182253
  2. Curr Oncol. 2023 Sep 15. 30(9): 8501-8549
      Glioblastoma is the most common malignant primary brain tumor in adults. The prognosis is extremely poor even with standard treatment of maximal safe resection, radiotherapy, and chemotherapy. Recurrence is inevitable within months, and treatment options are very limited. Chimeric antigen receptor T-cell therapy (CART) and bispecific T-cell engagers (TCEs) are two emerging immunotherapies that can redirect T-cells for tumor-specific killing and have shown remarkable success in hematological malignancies and been under extensive study for application in glioblastoma. While there have been multiple clinical trials showing preliminary evidence of safety and efficacy for CART, bispecific TCEs are still in the early stages of clinical testing, with preclinical studies showing very promising results. However, there are multiple shared challenges that need to be addressed in the future, including the route of delivery, antigen escape, the immunosuppressive tumor microenvironment, and toxicity resulting from the limited choice of tumor-specific antigens. Efforts are underway to optimize the design of both these treatments and find the ideal combination therapy to overcome these challenges. In this review, we describe the work that has been performed as well as novel approaches in glioblastoma and in other solid tumors that may be applicable in the future.
    Keywords:  BiTE; CART; bispecific T-cell engager; bispecific antibodies; chimeric antigen receptor; glioblastoma
    DOI:  https://doi.org/10.3390/curroncol30090619