Related Experiment Video
Updated: May 1, 2026
Experimental Melanoma Immunotherapy Model Using Tumor Vaccination with a Hematopoietic Cytokine
Published on: February 24, 2023
Complete regression and systemic protective immune responses obtained in B16 melanomas after treatment with LTX-315
Ketil André Camilio1, Gerd Berge, Chandra Sekhar Ravuri
1Lytix Biopharma AS, P.O. Box 6447, 9294, Tromsø, Norway.
Abstract:
Malignant melanoma is the most aggressive and deadliest form of skin cancer due to its highly metastatic potential, which calls for new and improved therapies. Cationic antimicrobial peptides (CAPs) are naturally occurring molecules found in most species, in which they play a significant role in the first line of defense against pathogens, and several CAPs have shown promising potential as novel anticancer agents. Structure-activity relationship studies on the CAP bovine lactoferricin allowed us to de novo design short chemically modified lytic anticancer peptides. In the present study, we investigated the in vivo antitumor effects of LTX-315 against intradermally established B16 melanomas in syngeneic mice. Intratumoral administration of LTX-315 resulted in tumor necrosis and the infiltration of immune cells into the tumor parenchyma followed by complete regression of the tumor in the majority of the animals. LTX-315 induced the release of danger-associated molecular pattern molecules such as the high mobility group box-1 protein in vitro and the subsequent upregulation of proinflammatory cytokines such as interleukin (IL) 1β, IL6 and IL18 in vivo. Animals cured by LTX-315 treatment were protected against a re-challenge with live B16 tumor cells both intradermally and intravenously. Together, our data indicate that intratumoral treatment with LTX-315 can provide local tumor control followed by protective immune responses and has potential as a new immunotherapeutic agent.
Insights
LTX-315, a novel anticancer peptide, effectively eradicated melanoma tumors in mice by triggering immune responses. This peptide shows promise as a new immunotherapeutic agent for skin cancer treatment.
Area of Science:
- Oncology
- Immunology
- Biochemistry
Background:
- Malignant melanoma is a deadly skin cancer with high metastatic potential, necessitating novel therapies.
- Cationic antimicrobial peptides (CAPs) are investigated for their anticancer properties.
- LTX-315 is a de novo designed, chemically modified peptide based on bovine lactoferricin.
Purpose of the Study:
- To evaluate the in vivo antitumor effects of LTX-315 against B16 melanomas.
- To determine the immunological mechanisms underlying LTX-315's efficacy.
- To assess the potential of LTX-315 as an immunotherapeutic agent.
Main Methods:
- Intratumoral administration of LTX-315 in a syngeneic mouse model of melanoma.
- Assessment of tumor response, including necrosis and immune cell infiltration.
- In vitro and in vivo analysis of danger-associated molecular pattern (DAMP) molecule and cytokine release.
- Tumor re-challenge experiments to evaluate protective immunity.
Main Results:
- LTX-315 treatment led to tumor necrosis and complete regression in most mice.
- Significant infiltration of immune cells into the tumor was observed.
- LTX-315 induced the release of high mobility group box-1 (HMGB1) and upregulated pro-inflammatory cytokines (IL-1β, IL-6, IL-18).
- Cured animals developed protective immunity against subsequent tumor cell challenges.
Conclusions:
- Intratumoral LTX-315 demonstrates potent antitumor activity and promotes anti-melanoma immune responses.
- LTX-315 has potential as a novel immunotherapeutic agent for melanoma.
- The observed immune activation suggests a dual mechanism of action involving direct tumor cell killing and host immune system stimulation.
