Hydroxycamptothecin-induced apoptotic gene expression profiling by PCR array in human Tenon's capsule fibroblasts

Area of Science:

• Cell Biology
• Molecular Biology
• Pharmacology

Background:

• Fibroblast apoptosis is implicated in various physiological and pathological processes.
• Hydroxycamptothecin (HCPT) is a known inducer of apoptosis in various cell types.
• Understanding the specific mechanisms of HCPT-induced apoptosis in fibroblasts is crucial for therapeutic applications.

Purpose of the Study:

• To investigate the apoptotic gene expression profile in human Tenon's capsule fibroblasts (HTCFs) treated with HCPT.
• To identify the key genes involved in HCPT-induced apoptotic signaling in HTCFs.
• To elucidate the role of mitochondrial and endoplasmic reticulum stress in HCPT-induced apoptosis.

Main Methods:

• Human Tenon's capsule fibroblasts (HTCFs) were treated with varying concentrations of HCPT (0, 0.25, 4 mg/L) for different durations (24, 48, 72 h).
• Cell proliferation was assessed using MTT assay.
• Apoptosis was quantified using Annexin V-FITC/PI staining and flow cytometry.
• Apoptotic gene expression profiling was performed using a PCR array.

Main Results:

• HCPT demonstrated anti-proliferative effects and induced apoptosis in HTCFs in a concentration- and time-dependent manner.
• A significant increase in apoptotic HTCFs (9.38%) was observed at 4 mg/L HCPT.
• PCR array analysis revealed significant alterations in 88 apoptotic genes, with notable upregulation of CHOP and downregulation of XIAP.

Conclusions:

• HCPT effectively induces apoptosis in human Tenon's capsule fibroblasts.
• The mechanism involves the activation of mitochondrial and endoplasmic reticulum stress pathways.
• Downregulation of XIAP is a key event in HCPT-mediated apoptosis of HTCFs.