LabMedica

Download Mobile App
Recent News Expo Clinical Chem. Molecular Diagnostics Hematology Immunology Microbiology Pathology Technology Industry Focus

Manipulating MicroRNA Levels May Return Cancer Cells to Normalcy

By LabMedica International staff writers
Posted on 07 Sep 2015
Print article
A possible approach for inducing cancer cells to revert to a precancerous state is based on the protein PLEKHA7 (Pleckstrin homology domain-containing family A member 7), which regulates the levels of select microRNAs (miRNAs) to suppress expression of cell transforming factors.

Investigators at the Mayo Clinic (Jacksonville, FL, USA) had been trying to explain why two proteins, E-cadherin and p120 catenin (catenin [cadherin-associated protein], delta 1 or p120) sometimes seemed to suppress cancer formation and at other times seemed to promote it.

Cadherins (named for “calcium-dependent adhesion”) are a class of type-1 transmembrane proteins. They play important roles in cell adhesion, ensuring that cells within tissues are bound together. They are dependent on calcium (Ca2+) ions to function, hence their name. Loss of E-cadherin function or expression has been implicated in cancer progression and metastasis. E-cadherin downregulation decreases the strength of cellular adhesion within a tissue, resulting in an increase in cellular motility. This in turn may allow cancer cells to cross the basement membrane and invade surrounding tissues.

The gene for p120 encodes a member of the Armadillo protein family, which function in adhesion between cells and signal transduction.

The investigators reported in the August 24, 2015, online edition of the journal Nature Cell Biology that PLEKHA7 recruited the so-called "microprocessor complex" (association of DROSHA and DGCR8 proteins) to a growth-inhibiting site (apical zonula adherens) in epithelial cells instead of sites at basolateral areas of cell–cell contact. If the microprocessor complex was recruited to a basolateral area instead of to the apical zonula adherens, miRNA regulation was disrupted, causing tumor growth. Restoring normal miRNA levels in tumor cells reversed that aberrant cell growth.

"We believe that loss of the apical PLEKHA7-microprocessor complex is an early and somewhat universal event in cancer," said senior author Dr. Panos Anastasiadis, chairman of the department of cancer biology at the Mayo Clinic. "In the vast majority of human tumor samples we examined, this apical structure is absent, although E-cadherin and p120 are still present. This produces the equivalent of a speeding car that has a lot of gas (the bad p120) and no brakes (the PLEKHA7-microprocessor complex). By administering the affected miRNAs in cancer cells to restore their normal levels, we should be able to reestablish the brakes and restore normal cell function. Initial experiments in some aggressive types of cancer are indeed very promising."

Related Links:

Mayo Clinic


Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Magnetic Bead Separation Modules
MAG and HEATMAG
Complement 3 (C3) Test
GPP-100 C3 Kit
Gold Member
Real-time PCR System
GentierX3 Series

Print article

Channels

Clinical Chemistry

view channel
Image: The 3D printed miniature ionizer is a key component of a mass spectrometer (Photo courtesy of MIT)

3D Printed Point-Of-Care Mass Spectrometer Outperforms State-Of-The-Art Models

Mass spectrometry is a precise technique for identifying the chemical components of a sample and has significant potential for monitoring chronic illness health states, such as measuring hormone levels... Read more

Hematology

view channel
Image: The CAPILLARYS 3 DBS devices have received U.S. FDA 510(k) clearance (Photo courtesy of Sebia)

Next Generation Instrument Screens for Hemoglobin Disorders in Newborns

Hemoglobinopathies, the most widespread inherited conditions globally, affect about 7% of the population as carriers, with 2.7% of newborns being born with these conditions. The spectrum of clinical manifestations... Read more

Immunology

view channel
Image: The AI predictive model identifies the most potent cancer killing immune cells for use in immunotherapies (Photo courtesy of Shutterstock)

AI Predicts Tumor-Killing Cells with High Accuracy

Cellular immunotherapy involves extracting immune cells from a patient's tumor, potentially enhancing their cancer-fighting capabilities through engineering, and then expanding and reintroducing them into the body.... Read more

Microbiology

view channel
Image: The T-SPOT.TB test is now paired with the Auto-Pure 2400 liquid handling platform for accurate TB testing (Photo courtesy of Shutterstock)

Integrated Solution Ushers New Era of Automated Tuberculosis Testing

Tuberculosis (TB) is responsible for 1.3 million deaths every year, positioning it as one of the top killers globally due to a single infectious agent. In 2022, around 10.6 million people were diagnosed... Read more