TSPAN8

TSPAN8, alias CO-029/TM4SF3, is a member of the tetratransmembrane protein superfamily (TM4SF), which is highly expressed mainly in a variety of tumours and may contribute to tumour metastasis and progression by promoting vascular regeneration, as well as enhancing tumour cell migration and invasion, etc. The mechanism of action of TSPAN8 is related to its localisation at the cell membrane, where it can function through the formation of homo- or hetero-dimers with other protein molecules to form multimeric complexes. dimers with other protein molecules at the plasma membrane to form multimeric complexes, thus exerting its function. In addition, TSPAN8 can bind to non-integrin chaperones such as EWI-F, EPCAM, CD13, PKC, and PI4KII, etc.

The biological significance of TSPAN8 mainly lies in its regulatory role in tumourigenesis and development. It was found that TSPAN8 was activated in the EGF/EGFR signalling pathway during breast cancer progression, and TSPAN8 transcription was upregulated through SOX9.High expression of TSPAN8 was associated with the properties of tumour stem cells and correlated with treatment resistance and poor prognosis.TSPAN8 could also enhance the anti-apoptotic ability of cancer cells through activation of the PI3K-AKT signalling pathway. In addition, TSPAN8 expression has been associated with intercellular communication in the tumour microenvironment, where it is enriched in exosomes and may influence tumour metastasis through extracellular vesicles for intercellular signalling. Therefore, TSPAN8 is a potential target in tumour therapy.