p53 nuclear immunostaining and gene mutations in non-small-cell lung cancer and their effects on patient survival

e20580 Background: Small cell lung cancer (SCLC) is an aggressive neuroendocrine subtype of lung cancer with high mortality. Recently, Immune checkpoint inhibitors (ICIs) have been shown to have the potential to improve the prognosis of SCLC, but little is known about immunotherapeutic biomarkers. Homologous recombination deficiency (HRD) is demonstrated to be a response predictor to immunotherapies in gynecologic cancers, while limited studies were reported in small cell lung cancer. Herein, we analyze the mutational pattern of HRR related genes in a Chinese SCLC cohort and further analyze the relationship between HRR-gene mutations and tumor mutational burden. Methods: Target gene sequencing (543 genes) was performed in 133 Genecast cohort with small cell lung cancer. PD-L1 expression were evaluated for 90 among 133 patients using the SP142 PD-L1 immunohistochemistry assay. Results: Among 133 patients, 47 (35.3%) had HRR-gene mutations. ATM (8.3%), NBN (4.5%) and BRCA2 (4.5%) were the top 3 mutated HRR-gene in the cohort，followed by ATR (3.8%), BARD1 (3.8%), BRCA1 (3.8%), PALB2 (3.8%), RAD50 (3.8%), CHEK2 (3.0%), BLM (3.0%), BRIP1(2.3%), CHEK1(1.5%), RAD52(1.5%), and MRE11A (0.8%). Pathogenic somatic and germline mutations of HRR genes were identified in 11 (11/47, 23.4%) and 3 (3/47, 6.4%) patients, respectively. 1 (1/47, 2.1%) patient carried both germline and somatic variants. Genomic landscape revealed that TP53 and RB1 were commonly mutated genes in SCLC cohort. Mutations in KMT2D, AR and RTK-RAS pathway occurred more frequently in the HRR-Mut group, compared with the wildtype ones. Furthermore, we found that mutations in HRR-gene were associated with high TMB (Wilcoxon, p = 0.048), and patients with high TMB (≥median) showed a higher proportion of positive PD-L1 expression in 90 SCLC patients. Conclusions: Our data indicated that genomic alterations associated with HRR-genes have a positive correlation with high TMB, and detection of HRR-gene mutation status probably could help identify patients who might benefit from immune checkpoint blockade therapy. Keywords: Small cell lung cancer, Homologous recombination deficiency, Immunotherapy.

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Influence of tumour laterality on patient survival in non-small cell lung cancer after radiotherapy

Radiotherapy and Oncology ◽

10.1016/j.radonc.2019.04.022 ◽

2019 ◽

Vol 137 ◽

pp. 71-76 ◽

Cited By ~ 3

Author(s):

Alan McWilliam ◽

Eliana Vasquez Osorio ◽

Corinne Faivre-Finn ◽

Marcel van Herk

Keyword(s):

Lung Cancer ◽

Small Cell Lung Cancer ◽

Cell Lung Cancer ◽

Patient Survival ◽

Small Cell ◽

Small Cell Lung

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Genomic based analyses reveal unique mutational profiling and identify prognostic biomarker for overall survival in Chinese small-cell lung cancer

Japanese Journal of Clinical Oncology ◽

10.1093/jjco/hyz131 ◽

2019 ◽

Vol 49 (12) ◽

pp. 1143-1150 ◽

Cited By ~ 1

Author(s):

Yu Wang ◽

Xiao Han ◽

Xingwen Wang ◽

Wei Sheng ◽

Zheng Chen ◽

...

Keyword(s):

Lung Cancer ◽

Small Cell Lung Cancer ◽

Cell Lung Cancer ◽

Gene Mutations ◽

Small Cell ◽

Loss Of Function ◽

Small Cell Lung ◽

Mutational Profiling ◽

Mutation Burden ◽

Clonal Mutation

Abstract Objective As an aggressive subtype of lung cancer, small-cell lung cancer (SCLC) presents a poor prognosis. Although molecular and clinical characteristics have been established for SCLC, limited investigation has been performed for predicting survival of SCLC patients. Methods Genomic alterations were profiled in Chinese SCLC patients (N = 37) using targeted sequencing. Clonal mutation burden (CMB) integrated the number of mutations with the clonal structure of the tumor. Specific pathways involving DNA damage repair (DDR) and cell cycle as well as CMB were studied as potential biomarkers for prognosis of SCLC. Results TP53 and RB1 gene mutations were the most common alterations (91.9% and 83.8%, respectively), followed by LRP1B, FAM135B, SPTA1, KMT2D, FAT1, and NOTCH3. Survival analysis revealed that mutation status of the DDR pathway was associated with worse OS in our cohort. Importantly, patients with higher CMB exhibited worse OS in our cohort and this observation was successfully validated in the cBioportal cohort. Moreover, multivariate analysis demonstrated CMB as a promising independent prognostic factor for OS in Chinese SCLC patients. Interestingly, patients with loss of function of RB1, validated by immunohistochemistry staining, appeared to have worse OS. Conclusions The mutational profiling of Chinese SCLC patients signified an ethnicity dependent component. CMB was firstly found to be associated with OS of Chinese SCLC patients and could be regarded as a prognostic marker for SCLC.

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