2,5-Dimethyl-celecoxib inhibits cell cycle progression and induces apoptosis in human leukemia cells

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Cyclooxygenase-2 (COX-2) plays a key role in cancer progression, leading to the development of COX-2 inhibitors for cancer treatment.
• Celecoxib, a COX-2 inhibitor, has shown antitumor effects but is associated with cardiovascular risks, necessitating alternative strategies.
• 2,5-dimethyl-celecoxib (DMC) is a celecoxib analog lacking COX-2 inhibitory activity, presenting a potential alternative for cancer therapy.

Purpose of the Study:

• To investigate the anti-hematologic cancer effects of 2,5-dimethyl-celecoxib (DMC).
• To elucidate the mechanisms underlying DMC's action on leukemic cell lines.

Main Methods:

• Treatment of human hematologic cancer cell lines (U937, Jurkat, Hel, Raji, K562) with DMC.
• Assessment of cell growth inhibition and apoptosis induction.
• Analysis of protein expression levels (Mcl-1, GRP78, c-Myc, cyclin D1, p27, survivin) and cell cycle progression.

Main Results:

• DMC significantly reduced growth and induced apoptosis in all tested leukemic cell lines more effectively than celecoxib.
• DMC treatment led to Mcl-1 protein downregulation and induced endoplasmic reticulum stress, evidenced by decreased GRP78 expression.
• DMC altered cell cycle progression at G1/S transition, affecting c-Myc, cyclin D1, and p27 expression, and also impacted mitotic progression by downregulating survivin.

Conclusions:

• DMC demonstrates potent anti-leukemic activity through COX-2 independent mechanisms.
• DMC induces cancer cell death via endoplasmic reticulum stress, cell cycle arrest, and modulation of key regulatory proteins.
• DMC represents a promising therapeutic candidate for hematologic malignancies, warranting further investigation.