Identification and Characterization of Alternatively Spliced Transcript Isoforms of IRX4 in Prostate Cancer

Area of Science:

• Molecular Biology
• Genetics
• Oncology

Background:

• Alternative splicing (AS) is crucial for genomic stability but aberrant AS drives cancer progression, including in prostate cancer (PCa).
• Iroquois-class homeodomain protein 4 (IRX4) has been identified as a potential tumor suppressor in PCa.
• Understanding IRX4 transcript variants and their roles is essential for PCa management.

Purpose of the Study:

• To characterize IRX4 transcripts and protein isoforms in prostate cancer.
• To investigate the expression profiles and clinical relevance of IRX4 variants in PCa.
• To explore the potential diagnostic and therapeutic implications of IRX4 in PCa.

Main Methods:

• Reverse transcription-polymerase chain reaction (RT-PCR) and sequencing were used to identify and characterize IRX4 transcripts.
• Expression levels were analyzed in PCa cell lines and clinical specimens (TCGA).
• Mass spectrometry was employed to identify IRX4 protein isoforms.

Main Results:

• Twelve IRX4 transcripts, including seven novel ones, were characterized with distinct expression patterns in PCa cell lines.
• These transcripts were overexpressed in PCa cell lines and clinical samples, correlating with PCa progression.
• Four IRX4 protein isoforms were identified, including two novel ones lacking functional domains, and a risk-associated SNP (rs12653946) correlated with lower IRX4 levels.

Conclusions:

• Aberrant IRX4 splicing and novel isoforms are implicated in prostate cancer progression.
• IRX4 isoforms may contribute to PCa hallmarks, offering potential diagnostic and prognostic value.
• Further research into IRX4 isoforms could lead to novel therapeutic strategies for PCa.