LTX-315 (Oncopore), the oncolytic peptide, inhibits cancer cells through Bax/Bak-regulated mitochondrial membrane permeabilization.

LTX-315 is highly active against both murine and human melanoma cell lines in vitro. while displaying low EC50 cytotoxic activity against human red blood cells. LTX-315 has been shown to induce the release of ATP and HMGB1 in vitro, both being DAMPs involved in ICD[1].

when syngeneic B16 melanomas are treated intralesionally, a majority of the animals (~80%) treated with LTX-315 experience a complete and long-lasting tumor regression. LTX-315 injection induces an extensive hemorrhagic necrosis of the tumor parenchyma and a massive infiltration of CD3+ T cells, indicating that the peptide induces a type of cell death that leads to an increase in the number of tumor-infiltrating lymphocytes (TILs). treatment of a single tumor with LTX-315 generates a systemic anti-tumor immune response that eradicated distant lesions and prevented reoccurrence following tumor rechallenge[1].

LTX-315 is prepared in FBS-free culture medium.Tumor cells are incubated for 4 hours with 10 concentrations of LTX-315 in 1/4 dilution step with a top dose of 400 μM, with 1% (final concentration) Triton X-100 as positive control and FBS-free culture medium as negative control. Cell cytotoxicity is measured using the MTS assay

LTX-315 is dissolved in saline.Mice: Tumor cells are harvested, ished in RPMI-1640 and injected intradermally (i.d.) into the right side of the abdomen in C57BL/6 mice. Palpable tumors are injected i.t. with single doses of LTX-315 or LTX-328 dissolved in saline (1.0 mg peptide/50 μL saline) once a day for 3 consecutive days, and the vehicle control is saline only (0.9% NaCl in sterile water). Tumor size is measured using an electronic caliper