Measuring protein levels could predict early-stage NSCLC patient outcomes

The study investigates measuring cellular CDK levels to predict the outcome of early stage-NSCLC patients.

Non small-cell lung cancer (NSCLC) is a common type of lung cancer that can be difficult to treat. Even early-stage NSCLC treated with surgery has a poor 5-year survival rate (65%) due to recurrence (cancer returns) and metastasis (cancer spreads). Certain NSCLC patients have been shown to benefit from receiving post-surgery platinum-based chemotherapies (drugs used to treat cancer) for example Cisplatin (Platinol, Cisplatinum). However chemotherapy is not normally offered to those with early stage disease.

Biomarkers (distinguishing feature of disease) can predict the risk of recurrence, patient outcome or response to chemotherapy. Biomarkers appropriate for this in early-stage NSCLC patients have proved difficult to discover. One possibility is investigating the activity of cyclin-dependent kinases (CDKs) (cell proteins that control cell division). Investigations of certain CDKs have been shown to be related to patient outcome and sensitivity to chemotherapy.

This investigation focused on measuring CDK1 and CDK2 levels of early stage-NSCLC patients to try and predict outcomes.

171 patients (average age of 70) were chosen as part of this study. Patients were divided based on cancer type; squamous cell carcinoma (SCC) in 31% and adenocarcinoma in 69%. Tissue samples were tested for the activity of CDK1 and CDK2. Low level CDK1 activity was defined as having a level of 12.6 maU/Eu or under (54% of patients). A value of 222 maU/Eu was established as a low level of CDK2 (77% of patients).

Recurrence-free survival (time between surgery and recurrence) and overall survival (time between surgery and death) were investigated. At the final follow up (average 44 months) the overall recurrence rate was 22% (recurrence at or close to the original site in 8% and recurrence at distant sites in 14%) and the overall survival rate was 78%.

Patients with high CDK1 levels had 2.25 times the risk of recurrence compared to patients in the low CDK1 group. CDK2 was not associated with recurrence rates.

Patients with high CDK2 levels had a 97% increased risk of death compared to those with low levels. CDK1 was not associated with the risk of death.

In patients with recurrent disease who underwent surgery and treatment with platinum-based chemotherapy CDK2 levels were found to be predictive of outcome and sensitivity to the therapy.

The study concluded that measuring CDK1 was an independent method of predicting cancer reoccurrence. CDK2 was able to predict overall survival and response to platinum based chemotherapies.

The paper itself suggests that certain subgroup analyses were lacking in numbers. Further investigations would require larger study numbers.

If you have early stage NSCLC consider having your CDK levels measured to help predict outcomes.