Methylation patterns and chemosensitivity in NSCLC

Real-time monitoring efficiency and toxicity of chemotherapy in patients with advanced lung cancer

Background

The Response Evaluation Criteria in Solid Tumors (RECIST) guideline and Common Terminology Criteria for Adverse Events (CTCAE) criteria are used to assess chemotherapy efficiency and toxicity in patients with advanced lung cancer. However, no real-time, synchronous indicators that can evaluate chemotherapy outcomes are available. We wanted to evaluate tumor response and toxicity in advanced lung cancer chemotherapy by using a novel synchronous strategy.

Results

We enrolled 316 patients with advanced lung cancer who were treated with cisplatin-based therapy and followed up them for 3 years. Plasma was obtained before and after every chemotherapy cycle. We quantitative assayed total plasma DNA and methylation of the APC/RASSF1A genes. Four parameters were assessed: methylation level before chemotherapy (meth_0 h), methylation level 24 h after chemotherapy (meth_24 h), total plasma DNA concentration before chemotherapy (DNA_0 h), and total plasma DNA concentration 24 h after chemotherapy (DNA_24 h). When meth_24 h > meth_0 h of at least one gene was used to predict tumor response, the correct prediction rate was 82.4 %. Additionally, patients for whom DNA_24 h/DNA_0 h ≤ 2 had mild toxicities. Therefore, meth_24 h > meth_0 h and DNA_24 h/DNA_0 h ≤ 2 were defined as criteria for better tumor response and fewer adverse events with a high correct prediction rate (84.7 %).

Conclusions

Quantitative analysis of total plasma DNA and plasma APC/RASSF1A methylation provide a real-time synchronous rapid monitoring indicator for therapeutic outcomes of advanced lung cancer, which could be a reference or supplementary guidelines in evaluating chemotherapy effects.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-015-0150-9) contains supplementary material, which is available to authorized users.

The potential of circulating nucleic acids as components of companion diagnostics for predicting and monitoring chemotherapy response

An effective personalized medicine is associated with the ability of identifying cancer patients who respond to anticancer targeted therapies. Therefore, new companion biomarkers that facilitate drug development are urgently needed. Since clinically relevant genetic and epigenetic alterations can be detected in cell-free nucleic acids in the blood circulation of cancer patients, these molecules may be a new promising class of potential liquid biomarkers. They can be obtained in real-time from blood, and their analyses could, consequently, facilitate treatment decisions. Screening of these liquid biopsies may provide information on the aberrant signaling pathway that should be blocked by the chosen targeted therapy. This article will discuss the potential of circulating nucleic acids as therapeutics for overcoming chemotherapeutic resistance in anticancer strategies.

[DNA methylation and non-small cell lung cancer]

基因组DNA甲基化是目前发现的最主要的一种表观遗传修饰形式，高甲基化（hypermethylation）的DNA染色质构象发生改变，导致抑癌基因转录失活，在肿瘤发生发展中具有重要意义。近年来，DNA甲基化在肺癌，主要是非小细胞肺癌（non-small cell lung cancer, NSCLC）的研究中取得较大进展，为NSCLC早期诊断、风险评估、预后判断和干预治疗提供了新的靶点。

Molecular biomarkers for predicting chemotherapy response in lung cancer

BACKGROUND

Chemotherapy in non-small-cell lung cancer (NSCLC) has reached a plateau, with no evidence of substantial improvement in survival. However, recent advances in the management of lung cancer have paved the way for the optimization of treatment. Several lines of evidence indicate that multiple genetic disturbances found in human cancer cell lines and in the tumors of NSCLC patients have a role as predictive markers for response and survival with chemotherapy regimens now in use.

OBJECTIVE

This review highlights relevant translational research findings on potential predictive markers in lung cancer with therapeutic impact in both the near and distant future.

CONCLUSION

The next step is to develop clinical trials that will prospectively validate the benefits of customizing chemotherapy, which should translate into an improvement in outcome in NSCLC patients.