HERV-K Env Specific Neutra™ Antibody Products

Human endogenous retroviruses (HERVs) are viral elements naturally found in the human genome, resembling and originating from retroviruses. Among these, HERV-K is the most active ERV family member in the human genome, and its expression has been widely observed in cancers. The type 1 HERV-K envelope (Env) proteins have dual roles: on the one hand, they can activate both innate and adaptive immunity, leading to inflammatory, cytotoxic, and apoptotic responses; on the other hand, they possess immunosuppressive properties that downregulate the immune response. Additionally, HERV Env proteins have been implicated in inducing abnormal cell-cell fusion, potentially promoting tumor formation and metastasis.

Fig.1 The general structure of HERV DNA sequences.^{1, 3}

HERV-K Env and Oncogenesis

Several previous studies have shown that HERV-K plays a role in the formation of certain types of tumors in humans, such as melanoma, colorectal tumors, ovarian cancer, prostate cancer, teratocarcinoma, osteosarcoma, and so on, as shown in Fig.2. In these tumors, the levels of immune responses, particularly antibodies, induced against HERV-K, are found to be higher in patients diagnosed with cancer compared to normal individuals.

Fig.2 The tumorigenic roles of HERV-K Env in various malignancies.^{2, 3}

The env gene encodes a precursor protein that is cleaved into two subunits: SU (surface) and TM (transmembrane). SU acts as the viral anti-receptor, while TM has fusogenic and immunosuppressive activities. Both subunits contribute to the oncogenic potential of the Env protein. The adhesion function of SU and the fusogenic function of TM can result in cell-cell fusion and syncytia formation, thereby supporting tumorigenicity and chromosomal instability. Additionally, TM's immunosuppressive activity may facilitate immune evasion in tumor cells by inhibiting cytotoxic T lymphocyte (CTL) and apoptotic responses. Together, these processes influence tumor growth, tissue invasion, and migration, as illustrated in Fig. 3.

Fig.3 Mechanisms of Env Protein in Oncogenic Roles.^{1, 3}

Anti-HERV-K Env Protein Antibodies

Previous research indicates that HERV-K Env holds promise as a cancer biomarker and a potential immunotherapy target. Typically expressed on HERV-K-affected cells' surfaces, the HERV-K Env protein is a focus for cancer therapy development. Monoclonal antibodies (mAbs) targeting HERV-K Env exhibit potential in tumor immune therapy. Studies show that these mAbs can impede cancer cell growth and prompt apoptosis in vitro. Notably, mAbs can also target T-cell responses, specifically targeting a conserved segment of the HERV-K envelope. This action prevents glycosylation, which is crucial for protein processing, receptor binding, and immune evasion while preserving its functional folded state.

Creative Biolabs has a wealth of experience in antibody production and provides a wide variety of anti-HERV-K Env antibody products customized for researchers globally. Contact us for more information.

REFERENCES

1. Grandi, Nicole, and Enzo Tramontano. "HERV envelope proteins: physiological role and pathogenic potential in cancer and autoimmunity." Frontiers in microbiology 9 (2018): 333020.
2. Hosseiniporgham, Sepideh, and Leonardo Antonio Sechi. "Anti-HERV-K drugs and vaccines, possible therapies against tumors." Vaccines 11.4 (2023): 751.
3. Under open access license CC BY 4.0, without modification.