Differential expression of RON in small and non-small cell lung cancers

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• Receptor tyrosine kinases (RTKs) play critical roles in cellular signaling pathways.
• RON, a MET-related RTK, is implicated in inflammation and has been found overexpressed in various cancers.
• Aberrant RON splicing and expression are linked to tumor growth and metastasis.

Purpose of the Study:

• To investigate the expression and potential therapeutic role of RON in lung cancer.
• To analyze total RON protein and its active form (phospho-RON) in diverse lung tumor types and metastatic samples.
• To identify novel RON splice variants and assess their functional significance.

Main Methods:

• Analysis of 175 archival lung tumor FFPE samples (NSCLC, SCLC, and metastatic forms).
• Detection of total RON and phospho-RON using specific antibodies.
• RT-PCR and RNA isolation to identify RON isoforms.
• Cell surface expression analysis in lung cancer cell lines.
• RON knockdown experiments to assess impact on cell viability and motility.

Main Results:

• Higher frequency and intensity of RON expression in SCLC and brain metastases compared to other lung tumors.
• The majority of expressed RON protein was in its active, phosphorylated form (phospho-RON).
• Identified novel RON isoforms (62 and 30 kDa) and characterized RON expression patterns (150 kDa in NSCLC, 120 kDa in SCLC).
• RON was detected on the cell surface of NSCLC cells.
• RON knockdown significantly reduced lung cancer cell viability and motility.

Conclusions:

• RON is frequently overexpressed and activated in lung cancers, especially SCLC and metastatic tumors.
• Specific RON isoforms and cell surface expression are observed in different lung cancer subtypes.
• RON plays a crucial role in lung cancer cell viability and motility.
• RON represents a promising therapeutic target for lung cancer treatment.