Epidermal Growth Factor Receptor Mutations Are Associated with Docetaxel Sensitivity in Lung Cancer

Identifying CDC7 as a synergistic target of chemotherapy in resistant small-cell lung cancer via CRISPR/Cas9 screening

There is currently a lack of efficacious treatments for patients with chemo-resistant small-cell lung cancer (SCLC), leading to poor prognoses. We examined a chemo-resistant SCLC cell line using genome-wide CRISPR/Cas9 screening and identified serine/threonine kinase cell division cycle 7 (CDC7) as a potential synergistic target. Silencing CDC7 in chemo-resistant SCLC cells decreased the IC₅₀ and improved the efficacy of chemotherapy. Based on the highest single agent model, the CDC7 inhibitor XL413 had a synergistic effect with both cisplatin and etoposide in chemo-resistant SCLC cells, but had no such effect in chemo-sensitive SCLC cells; the combination of XL413 and chemotherapy significantly inhibited cell growth. Western blot and flow cytometry showed that the combined treatments increased apoptosis, whereas XL413 alone had little effect on apoptosis. An analysis of cell cycle and cyclin protein levels indicated that the combination of XL413 and chemotherapy-induced G1/S phase arrest and DNA damage in chemo-resistant SCLC cells. Xenografted tumor and histoculture drug response assays using patient-derived xenografts showed that XL413 improved the efficacy of chemotherapy in vivo and with SCLC tissues. These results suggest that XL413 exerts a synergistic effect with chemotherapy on chemo-resistant SCLC.

Association between epidermal growth factor receptor gene mutation status and short‑term efficacy of first‑line platinum‑containing chemotherapy in advanced non‑small cell lung cancer

It remains undetermined whether there is an explicit association between the epidermal growth factor receptor (EGFR) gene mutation status and chemotherapy efficacy in non-small cell lung cancer (NSCLC) patients with advanced stages. Thus, the aim of the present retrospective study was to investigate the possible association between EGFR gene mutation status and the efficacy of first-line chemotherapy in patients with advanced NSCLC. In total, 52 patients who were diagnosed with NSCLC at Changzhou Tumor Hospital (Changzhou, China) from January 2015 to December 2018 were enrolled. All 52 patients received pemetrexed combined with platinum chemotherapy, for 21 days per cycle. After two cycles of treatment, the short-term clinical efficacy was assessed according to the Response Evaluation Criteria in Solid Tumours 1.1 guidelines. The objective response rate (ORR), disease control rate (DCR) and progression-free survival (PFS) rate were calculated at the end of the study (December 31, 2019). These patients also underwent second-generation gene sequencing before the potential association between mutations in the EGFR gene and chemotherapy efficacy was analyzed. In this group of patients, 25 cases (48.1%) were found to be harboring EGFR gene mutation, whilst 27 cases (51.9%) expressed wild-type EGFR. After receiving the first-line chemotherapy regimen, the ORR was determined to be 36.5%, the DCR was 71.2%, whereas the PFS period was 207 days. Following first-line chemotherapy, the DCR of patients with EGFR mutations (52%) was higher compared with those in patients harboring the wild-type EGFR (22%). By contrast, the PFS (260 days) of patients with EGFR mutations was longer compared with those in patients harboring wild-type EGFR (100 days). These differences were statistically significant (P<0.05). Multivariate analysis revealed that EGFR gene mutation was an independent predictor of PFS in patients with advanced NSCLC (P<0.05). To conclude, data from the present study suggest that EGFR gene mutation has independent predictive value for the efficacy of first-line chemotherapy in patients with advanced NSCLC.

Intratumoral gene expression of dihydrofolate reductase and folylpoly-c-glutamate synthetase affects the sensitivity to 5-fluorouracil in non-small cell lung cancer

BACKGROUND

Various factors related to the sensitivity of non-small cell lung carcinoma (NSCLC) to 5-fluorouracil (5-FU) have been reported, and some of them have been clinically applied. In this single-institutional prospective analysis, the mRNA expression level of five folic acid-associated enzymes was evaluated in surgical specimens of NSCLC. We investigated the correlation between the antitumor effect of 5-FU in NSCLC using an anticancer drug sensitivity test and the gene expression levels of five enzymes.

MATERIALS AND METHODS

Forty patients who underwent surgery for NSCLC were enrolled, and the antitumor effect was measured using an in vitro anticancer drug sensitivity test (histoculture drug response assay) using freshly resected specimens. In the same sample, the mRNA expression levels of five enzymes involved in the sensitivity to 5-FU were measured in the tumor using real-time PCR. The expression levels and the result of the sensitivity test were compared.

RESULTS

No correlation was found between dihydropyrimidine dehydrogenase (DPD), orotate phosphoribosyltransferase (OPRT), or DPD/OPRT expression and the antitumor effects of 5-FU. On the other hand, a correlation was found between thymidylate synthase (TS), folylpoly-c-glutamate synthetase (FPGS), and dihydrofolate reductase (DHFR) expression and 5-FU sensitivity.

CONCLUSION

Expression of FPGS and DHFR may be useful for predicting the efficacy of 5-FU-based chemotherapy for NSCLC.

Interactions of Self-Assembled Bletilla Striata Polysaccharide Nanoparticles with Bovine Serum Albumin and Biodistribution of Its Docetaxel-Loaded Nanoparticles

: Amphiphilic copolymers of stearic acid (SA)-modified Bletilla striata polysaccharides (BSPs-SA) with three different degrees of substitution (DSs) were synthesized. The effects of DS values on the properties of BSPs-SA nanoparticles were evaluated. Drug state, cytotoxicity, and histological studies were carried out. The affinity ability of bovine serum albumin (BSA) and the BSPs-SA nanoparticles was also characterized utilizing ultraviolet and fluorescence spectroscopy. Besides, the bioavailability and tissue distribution of docetaxel (DTX)-loaded BSPs-SA nanoparticles were also assessed. The results demonstrated that the DS increase of the hydrophobic stearic acid segment increased the negative charge, encapsulation efficiency, and drug-loading capacity while decreasing the critical aggregation concentration value as well as the release rate of docetaxel from the nanoparticles. Docetaxel was encapsulated in nanoparticles at the small molecules or had an amorphous status. The inhibitory capability of DTX-loaded BSPs-SA nanoparticles against 4T1 tumor cells was superior to that of Duopafei^®. The ultraviolet and fluorescence results exhibited a strong binding affinity between BSPs-SA nanoparticles and bovine serum albumin, but the conformation of bovine serum albumin was not altered. Additionally, the area under the concentration⁻time curve (AUC₀_⁻∞) of DTX-loaded BSPs-SA nanoparticles was about 1.42-fold higher compared with Duopafei^® in tumor-bearing mice. Docetaxel levels of DTX-loaded BSPs-SA nanoparticles in some organs changed, and more docetaxel accumulated in the liver, spleen, and the tumor compared with Duopafei^®. The experimental results provided a theoretical guidance for further applications of BSPs-SA conjugates as nanocarriers for delivering anticancer drugs.

[Association between the epidermal growth receptor status and the efficacy of first-line chemotherapy in patients with advanced non-small cell lung cancer]

背景与目的

表皮生长因子受体（epidermal growth factor receptor, EGFR）基因状态是表皮生长因子受体酪氨酸激酶抑制剂（epidermal growth factor receptor tyrosine kinase inhibitor, EGFR-TKI）疗效的预测因素，但其对化疗疗效的预测作用尚不明确。本研究旨在探讨对晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）患者一线化疗疗效的预测意义。

方法

收集首都医科大学附属北京胸科医院自2006年1月10日-2013年12月20日经组织病理学证实的181例Ⅲb期/Ⅳ期的NSCLC患者。分析EGFR基因状态、临床特征与化疗疗效及无疾病进展生存期（progression-free survival, PFS）之间的关系。

结果

181例患者均进行了EGFR基因检测，EGFR突变患者75例（41.4%），野生型为106例（58.6%）。全部患者均接受一线化疗，客观缓解率（objective response rate, ORR）为26.0%，疾病控制率（disease control rate, DCR）为70.2%。EGFR突变患者的DCR显著高于EGFR野生型患者高（84.0% vs 60.4%, P=0.001）。亚组分析显示，19外显子缺失突变患者化疗的ORR、DCR均高于EGFR野生型患者（P值分别为0.049，0.002）。21外显子L858R突变患者的DCR高于EGFR野生型患者（P=0.010）。全部患者中，168例患者可评价PFS，中位PFS为4.3个月，其中腺癌患者PFS较鳞癌患者延长（4.7个月 vs 3.0个月，P=0.036）；突变患者PFS长于野生型患者（6.3个月 vs 3.0个月，P=0.002）；体力状况评分（performance status, PS）0-1分组患者PFS较评分为2分延长（4.4个月 vs 0.7个月，P=0.016）。Cox多因素分析显示，EGFR突变是影响PFS的独立因素（HR=0.654, 95%CI: 0.470-0.909, P=0.012）。

结论

EGFR突变是晚期NSCLC患者一线化疗PFS的预测因素。

Predictive and prognostic value of de novo MET expression in patients with advanced non-small-cell lung cancer

BACKGROUND

Cellular-mesenchymal-epithelial transition (MET) protein has recently been identified as a novel target that shows promise for the treatment of non-small-cell lung cancer (NSCLC). However, the relationship between de novo MET expression and patient outcomes remains unclear.

METHODS

We reviewed the data of patients who had been diagnosed with NSCLC between December 2013 and October 2014. All the patients were evaluated for MET expression status. MET-positive was defined as having an H-score ≥ 60 by immunohistochemistry analysis. MET expression was analyzed in 158 patients who were negative for the common driver genes, including EGFR, ALK, KRAS and ROS1. A chi-squared test was used to assess the clinicopathological parameters. Multivariate analyses were performed using the Cox proportional hazards model.

RESULTS

MET data were available for analysis in 158 advanced NSCLC patients. Of these, based on the MET H-score criteria, the IHC-positive rate was 48.1% (76/158). There were more patients with adenocarcinoma in the MET-positive group compared with the MET-negative group (P=0.01). Nine patients with lymphoepithelioma-like carcinoma had no MET expression. There was no significant difference in overall survival (OS) between MET-positive and -negative patients. There was also no significant difference in the efficacy (Z=-0.44, P=0.66) or progression free survival (PFS) of first-line chemotherapy between the MET-positive and -negative patients (mPFS 6.8 months [95% CI: 5.4-8.2] vs. 5.9 months [5.5-6.3], P=0.92). In the cell model, the MET-positive cell showed no difference in chemotherapy but with a increase in percentage of growth inhibition upon treatment with MET inhibitor INC280 compared to MET-negative cell.

CONCLUSION

Our data showed that de novo MET expression was not rare. It was not a predictive or prognostic factor for stage IV NSCLC patients, but this should be confirmed in larger population cohort.

EGFR mutations as a prognostic and predictive marker in non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) has entered the age of individual treatment, and increasing point mutations of specific oncogenes and rearrangement of some chromosomes are biomarkers used to predict the therapeutic effect of targeted therapy. At present, there is a consensus among clinicians that epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have shown favorable efficacy in NSCLC patients with EGFR mutation, and some relevant research has suggested that the presence of EGFR mutations is a favorable prognostic marker. However, the association of EGFR mutation status with the responsiveness to conventional chemotherapy agents and survival in NSCLC patients is still unclear. This review provides an overview of and assesses the role of EGFR as a prognostic marker for postoperative patients and as a predictive marker for response to cytotoxic chemotherapy. In addition, we review the comparison of response to chemotherapy between EGFR mutations in exon 19 and in exon 21 and the predictive role of p.T790M mutation.

EGFR mutations and clinical outcomes of chemotherapy for advanced non-small cell lung cancer: a meta-analysis

BACKGROUND

This meta-analysis was performed to assess whether epidermal growth factor receptor (EGFR) mutation status was associated with objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) in patients with advanced non-small cell lung cancer (NSCLC) treated with chemotherapy.

METHOD

We systematically identified eligible articles investigating the effects of chemotherapy in patients with NSCLC stratified by EGFR mutation status. The summary risk ratio (RR) for ORR and hazard ratios (HRs) for both PFS and OS were calculated using the inverse variance formula of meta-analysis.

RESULTS

Identification for the current meta-analysis: 5 prospective studies (n=875) and 18 retrospective studies (n=1934) for ORR; 2 prospective studies (n=434) and 10 retrospective studies (n=947) for PFS; 2 prospective studies (n=438) and 7 retrospective studies (n=711) for OS. The ORR was significantly higher in patients with EGFR mutations in prospective studies (RR=1.42; 95% confidence interval [CI], 1.16-1.74; P=0.001), but not in retrospective studies (RR=1.12; 95% CI, 0.96-1.32; P=0.146). There was no obvious association between EGFR mutations and PFS both in prospective (HR=0.84; 95% CI: 0.65-1.09; P=0.197) and retrospective (HR=1.02; 95% CI: 0.87-1.18; P=0.838) studies. Association between EGFR mutations and OS was also not seen in prospective studies (HR=0.74; 95% CI: 0.27-2.05; P=0.566), but was seen in retrospective studies (HR=0.48; 95% CI: 0.33-0.72; P<0.001; I(2)=75.9%; P<0.001) with significant heterogeneity.

CONCLUSION

EGFR mutations in advanced NSCLC may be associated with higher ORRs to chemotherapy, but may have nothing to do with PFS and OS. Further prospective studies are required to identify the influence of EGFR mutations on chemotherapy effects in advanced NSCLC.

Correlation between EGFR mutation status and response to first-line platinum-based chemotherapy in patients with advanced non-small cell lung cancer

Background

The purpose of this research was to investigate the relationship between epidermal growth factor receptor (EGFR) mutations and the response to first-line chemotherapy in patients with advanced non-small cell lung cancer (NSCLC).

Methods

A total of 266 patients with stage IIIB or IV NSCLC who received platinum-based doublet therapies as first-line chemotherapy were investigated retrospectively, and their clinical data were assessed according to EGFR mutation.

Results

EGFR mutations were identified in 45.5% of patients. There was no significant difference in response rate between EGFR mutation carriers and EGFR wild-type carriers (P=0.484). Among the patients with Kirsten rat sarcoma viral oncogene homolog (KRAS) wild-type, however, those with EGFR mutations responded better to treatment than EGFR wild-type patients (46.2% versus 20.8%, P=0.043). The disease control rate associated with pemetrexed-based treatments was higher than for vinorelbine-based therapies in EGFR mutation patients (P=0.001). EGFR mutation was found in patients with longer progression-free survival and median survival time, and improved 1-year and 2-year overall survival when compared with EGFR wild-type patients (6.1 versus 5.0 months, P=0.004; 18.9 versus 13.8 months, P=0.001; 81.0% versus 63.4%, P=0.002; and 33.9% versus 22.8% P=0.044, respectively). Patients with the EGFR exon 19 mutation had longer progression-free survival than those with EGFR exon 21 mutation (P=0.007). Multivariate analysis showed that the response to first-line chemotherapy and the presence of EGFR mutations were independent prognostic factors in patients with advanced NSCLC.

Conclusion

Our data showed that the presence of EGFR mutations meant longer survival times for patients with advanced NSCLC who received platinum-based doublet first-line chemotherapy, especially in those with the exon 19 deletion mutation. Among KRAS wild-type patients, those with EGFR mutation responded better to first-line chemotherapy than EGFR wild-type patients.

[Personalized therapy in non-small cell lung cancer: from diagnosis to therapy]

Molecular targeted treatment, with broadening opportunities, plays an important role in the management of lung cancer patients, which renders molecular mapping of the tumor tissue crucial. In case of cytotoxic chemotherapy, there is no patient selection according to tissue biomarkers; however, there are expanding results that might help oncologists to use personalized chemotherapy in the near future. This may be of great importance when patients' age, performance status and/or co-morbidity make the applicability of chemotherapy uncertain. Nowadays, molecular targeted treatment gives hope mainly for patients with adenocarcinoma; however, promising therapeutic targets have already been outlined due to intensive research. In these days, we are experiencing a turbulent era of onco-pulmonology, which - despite all difficulties - gives hope for both patients and clinicians.

EGFR mutations as a predictive marker of cytotoxic chemotherapy

BACKGROUND

Epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) are important predictive markers for the response to EGFR-tyrosine kinase inhibitors (EGFR-TKIs). Whether EGFR mutations can also predict the clinical outcomes in NSCLC patients receiving chemotherapy has not yet been established.

METHODS

We included 217 locally advanced/metastatic NSCLC cases in our study cohort. Each patient had received platinum doublet chemotherapy as a first line treatment, and had been screened for an EGFR mutation.

RESULTS

The subject cohort comprised 80 EGFR wild type and 137 EGFR-mutated lung cancer patients. Gemcitabine-based and taxane-based regimens were administered in 131 (60.4%) and 86 (39.6%) cases, respectively. Among the patients with a wild type EGFR, there was no significant difference in the response rate (RR), disease control rate (DCR), or progression-free survival (PFS) between gemcitabine-based and taxane-based therapies. Among the patients with EGFR mutations, no difference in RR was observed between gemcitabine-based and taxane-based treatments. On the other hand, the DCR and PFS associated with taxane-based therapy were superior when compared with the gemcitabine-based treatments. When we analyzed patients with an EGFR exon 19 deletion, the PFS of the taxane treated cases was better than that of the gemcitabine treated cases (5.3 months vs 3.7 months, P=0.012).

CONCLUSIONS

Our current data indicate that lung cancer patients with EGFR-mutations had longer PFS with taxane than gemcitabine when receiving a platinum-based doublet regimen. The predictive meaning of EGFR mutations for cytotoxic chemotherapy should be further investigated.