TTF-1/Nkx2.1 functional connection with mutated EGFR relies on LRIG1 and β-catenin pathways in lung cancer cells

Significance of thyroid transcription factor 1 and Napsin A for prompting the status of EGFR mutations in lung adenocarcinoma patients

BACKGROUND

To evaluate the prompting value of thyroid transcription factor 1 (TTF-1) and Napsin A for the status of epidermal growth factor receptor (EGFR) mutations in an independent cohort of lung adenocarcinomas (LUADs) when genetic testing is unavailable.

METHODS

In this study, 976 untreated primary LUADs were retrospectively reviewed. The clinical and pathological data, including age, gender, smoking history, predictive values of TTF-1 and Napsin A, EGFR status, and tumor-node-metastasis (TNM) stage were obtained through medical records available in Shanxi Province Cancer Hospital. All patients were divided into 2 groups, a mutant group (n=362) and wild-type group (n=614), according to their EGFR status. The clinical data and the expression of TTF-1 and Napsin A were compared between the 2 groups. TTF-1 and Napsin A are detected by fully automated IHC.PCR was carried out to detect the EGFR mutation. Univariate and multivariate logistic regression analyses were undertaken to distinguish independent factors of EGFR mutations.

RESULTS

A total of 362 cases (37.1%) of EGFR mutations were detected, which were more frequent in females, never smokers, lymphatic metastasis, distant metastasis, and the positive expression of TTF-1 and Napsin A. Multivariate analysis indicated that females [odds ratio (OR), 1.950; 95% confidence interval (CI): 1.2958 to 2.938; P=0.001], never smokers (OR, 2.040; 95% CI: 1.345 to 3.094; P=0.001), and the positive expression of TTF-1 (OR, 2.366; 95% CI: 1.440 to 3.887; P=0.001) and Napsin A (OR, 2.295; 95% CI: 1.448 to 3.638; P<0.001) were effective prompting for EGFR mutations.

CONCLUSIONS

The positive expression of TTF-1 and Napsin A had the prompting value for EGFR mutations in patients with LUAD, and the indicators could be combined with other clinical characteristics to enhance the prediction of the EGFR status in LUAD.

Thyroid transcription factor 1 and p63 expression is associated with survival outcome in patients with non-small cell lung cancer treated with erlotinib

While erlotinib is primarily administered to patients with non-small cell lung cancer with sensitizing epidermal growth factor receptor (EGFR) mutations, it is also prescribed to patients with wild type (wt) EGFR in higher lines of treatment. However, there is no predictive marker for erlotinib efficacy in patients with EGFR wt. Certain immunohistochemical (IHC) parameters, including thyroid transcription factor 1 (TTF1) and p63, have been reported to indicate predictive power in patients with EGFR wt. The present study focused on retrospective data from the University Hospital in Pilsen using the TULUNG register. TTF1 and p63 expression data were extracted from the hospital information system and merged with registry data to calculate progression-free survival (PFS) and overall survival (OS) rates. A cohort of 345 patients with adenocarcinoma (ADC) or squamous cell carcinoma (SCC) exhibited similar erlotinib efficacies when TTF1 and p63 were ignored. However, significant differences were reported in PFS and OS rates of a subgroup of 126 patients where TTF1 and p63 parameters were known. In a univariate analysis, group A (ADC TTF1+/p63-) achieved PFS of 2.6 months, group B (SSC TTF1-/p63+) 1.9 months and group C (did not fit into groups A or B, i.e., ADC TTF1-/p63+ or SCC TTF1+/p63-) 1.4 months (P=0.006). Median OS was 14.2, 19.1 and 5.3 months for A, B and C, respectively (P=0.002). Furthermore, a multivariate analysis demonstrated IHC markers to be the only significant parameters for PFS and OS. Group C had a negative prognostic factor for PFS [hazard ratio (HR), 1.812; P=0.02] and OS (HR=2.367; P=0.01). In conclusion, patients with EGFR wt and lung carcinomas without TTF1 and p63 expression typical for ADC (TTF1+/p633-) or SCC (TTF1-/p63+) do not appear to be suitable candidates for erlotinib treatment.