Background

Data from meta-analyses support the use of induction or adjuvant platinum-based chemotherapy for locally advanced non-small cell lung cancers (NSCLCs). This phase 2 study assessed the role of induction cisplatin and docetaxel followed by surgery in patients with resectable stage I to III NSCLCs, followed by 12 months of adjuvant erlotinib.

Methods

Patients with resectable stage I to III NSCLCs received cisplatin 80 mg/m², docetaxel 75 mg/m² every 21 days for 3 cycles, followed by surgery, followed by adjuvant erlotinib for 12 months. The primary endpoint included safety. Long-term efficacy outcomes and exploratory analysis of intermediary endpoints are also reported (NCT00254384).

Results

Forty-seven eligible patients received a median of 3 cycles of induction treatment, 37 underwent surgical resection, and only 21 received adjuvant erlotinib. Two patients died in the perioperative period (1 sepsis during chemotherapy, 1 acute respiratory distress syndrome postoperatively). Most common grade 3 to 5 toxicities during chemotherapy included hypokalemia (8%), infection (7%), and granulocytopenia (25%). During adjuvant erlotinib, 14% of patients experienced grade 2 rash. Median overall survival was 3.4 years. Major pathologic responses in the primary tumor were observed in 19% (7 of 37) of patients and correlated with improved long-term overall survival. Complete pathologic response in mediastinal/hilar nodes also correlated with superior survival.

Conclusions

Induction cisplatin and docetaxel was well tolerated. Adjuvant erlotinib did not improve outcomes compared with historical controls. Major pathologic response predicted for improved long-term survival and is a suitable intermediary endpoint for future phase 2 studies.

Background

In this study, we investigated whether PKR protein expression is correlated with mRNA levels and also evaluated molecular biomarkers that are associated with PKR, such as phosphorylated PKR (p-PKR) and phosphorylated eIF2α (p-eIF2α).

Methodology and Findings

We determined the levels of PKR protein expression and mRNA in 36 fresh primary lung tumor tissues by using Western blot analysis and real-time reverse-transcriptase PCR (RT-PCR), respectively. We used tissue microarrays for immunohistochemical evaluation of the expression of p-PKR and p-eIF2α proteins. We demonstrated that PKR mRNA levels are significantly correlated with PKR protein levels (Spearman's rho = 0.55, p<0.001), suggesting that PKR protein levels in tumor samples are regulated by PKR mRNA. We also observed that the patients with high p-PKR or p-eIF2α expression had a significantly longer median survival than those with little or no p-PKR or p-eIF2α expression (p = 0.03 and p = 0.032, respectively). We further evaluated the prognostic effect of combined expression of p-PKR plus PKR and p-eIF2α plus PKR and found that both combinations were strong independent prognostic markers for overall patient survival on stage I and all stage patients.

Conclusions

Our findings suggest that PKR protein expression may controlled by transcription level. Combined expression levels of PKR and p-PKR or p-eIF2α can be new markers for predicting the prognosis of patients with NSCLC.

Background

In this study, we investigated whether PKR protein expression is correlated with mRNA levels and also evaluated molecular biomarkers that are associated with PKR, such as phosphorylated PKR (p-PKR) and phosphorylated eIF2α (p-eIF2α).

Methodology and findings

We determined the levels of PKR protein expression and mRNA in 36 fresh primary lung tumor tissues by using Western blot analysis and real-time reverse-transcriptase PCR (RT-PCR), respectively. We used tissue microarrays for immunohistochemical evaluation of the expression of p-PKR and p-eIF2α proteins. We demonstrated that PKR mRNA levels are significantly correlated with PKR protein levels (Spearman's rho = 0.55, p<0.001), suggesting that PKR protein levels in tumor samples are regulated by PKR mRNA. We also observed that the patients with high p-PKR or p-eIF2α expression had a significantly longer median survival than those with little or no p-PKR or p-eIF2α expression (p = 0.03 and p = 0.032, respectively). We further evaluated the prognostic effect of combined expression of p-PKR plus PKR and p-eIF2α plus PKR and found that both combinations were strong independent prognostic markers for overall patient survival on stage I and all stage patients.

Conclusions

Our findings suggest that PKR protein expression may controlled by transcription level. Combined expression levels of PKR and p-PKR or p-eIF2α can be new markers for predicting the prognosis of patients with NSCLC.