A new mechanism of lymphoma carcinogenesis

Professor Ai Kotani and graduate student Kai Kudo of Tokai University have been studying the role of EVs in the development of Epstein-Barr virus (EBV)-positive B-cell malignant lymphoma, but the mechanism of action has not been fully elucidated

In this study, the team demonstrated that sPLA2 secreted by tumor-associated macrophages (TAMs) in malignant lymphoma tissues can degrade EV phospholipids from tumor cells

On the other hand, this study shows that sPLA2 degrades not only lymphoma-derived EVs but also other cancer cell-derived EVs, and reveals that the sPLA2 EV axis is a common phenomenon in tumorigenesis

Glossary:

(1) Extracellular vesicles (EVs)

A particle released from a cell without a nucleus and surrounded by a lipid bilayer membrane

(2) Epstein-Barr virus (EBV)

A herpes virus with double-stranded DNA as its genome

(3) Secreted phospholipase A2 (sPLA2)

Of the two fatty acids that bind to phospholipids, a site called the sn-2 position usually binds unsaturated fatty acids, and sPLA2 is an enzyme that breaks down this part and releases fatty acids and lysophospholipids from phospholipids

(4) Tumor-associated macrophages (TAM)

Macrophages are important immune cells involved in removing foreign substances such as viruses and bacteria that invade the body

(5) Phospholipids

Amphiphilic lipids with hydrophilic molecules, such as choline and serine, and two fatty acids that exhibit hydrophobicity
.
It is a major component of biological membranes, such as plasma membranes and extracellular vesicle membranes
.
Furthermore, it has been clarified that there are many combinations due to any hydrophilic molecule and a variety of two fatty acids
.
Therefore, there are many molecular types of phospholipids
.

Secreted phospholipase A2 modifies extracellular vesicles and accelerates B cell lymphoma