Just changing the shape of fat cells can promote breast cancer growth

A new study by researchers at the University of Texas Southwestern suggests that fat cells that grow near breast cancer can be transformed into other cell types
that promote tumor growth.

Dr.
Qingzhang Zhu (left) and Dr.
Philipp Scherer

"We have identified new fat cell-derived cell types in the mammary gland that provide fertile soil for the invasion and growth of breast cancer tumors," said study leader Dr.
Philipp Scherer, professor of internal medicine and cell biology and a member of
the UTSW Harold C.
Simmons Comprehensive Cancer Center.

Obesity has long been considered a risk factor for breast cancer development and poor prognosis
.
Studies have shown that fat cells in close contact with breast tumor cells have a stronger ability to break down lipids, providing fuel
for invading tumor cells.
However, Dr.
Schaeler explained that it is unclear what other roles
these fat cells play in breast cancer progression.

To answer this question, Dr.
Qingzhang Zhu, an internal medicine lecturer in Scheler's lab, and his colleagues used a genetic technique to "paint" the fat cells of lab mice with a color that glows fluorescent, allowing them to be tracked for a long time
.
When the researchers implanted breast tumors into mice, or genetically manipulated rodents' own breast cells to convert them into tumor cells, they found that nearby fat cells contracted and took on a different morphology
than native fat cells.
Genetic testing was used to determine which genes were active in these fat cells, and the results showed that these cells first degenerated to the early stages of development and then gradually developed genetic markers for other cell types, including connective tissue cells, muscle cells, and immune cells
.

Adipocytes (the red part) take on a new morphology (the green part) when they come into contact with the tumor (the blue part
).

Further studies showed that these altered fat cells promoted the growth
of breast cancer tumors.
However, this property also relies heavily on their ability
to provide energy to neighboring tumor cells.
In addition, the nature of the cell types that fat cells transform into after losing lipids and the properties of their fat cells are also important, as they significantly increase local fibrosis, which leads to stiffness
of breast tissue.
When researchers enhance the lipid-storing capacity of mature fat cells, they stop transforming into other types of cells and no longer promote tumor growth
.

Dr.
Philipp Scherer said the mechanism of how fat cells transform into other cell types is unclear; However, a chemical signal from tumor cells may be responsible for
this phenomenon.
He and his colleagues plan to look for this signal and look for other ways to manipulate the system to inhibit breast cancer growth
.