Antitumor effects of erlotinib in combination with berberine in A431 cells

BACKGROUND

First-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as erlotinib, have been shown to target tumors with L858R (exon 21) and exon 19 deletions, resulting in significant clinical benefits. However, acquired resistance often occurs due to EGFR mutations. Therefore, novel therapeutic strategies for treatment of patients with EGFR-positive tumors are needed. Berberine (BBR) is an active alkaloid extracted from pharmaceutical plants such as Coptis chinensis. Berberine has been shown to significantly inhibit EGFR activity and mediate anticancer effects in multiple preclinical studies. We investigated whether combining BBR with erlotinib could augment erlotinib-induced cell growth inhibition of EGFR-positive cells in a mouse xenograft model.

METHODS

We examined the antitumor activities and potential mechanisms of erlotinib in combination with berberine in vitro and in vivo using the MTT assay, immunoblotting, flow cytometry, and tumor xenograft models.

RESULTS

In vitro studies with A431 cells showed that synergistic cell growth inhibition by the combination of BBR and erlotinib was associated with significantly greater inhibition of pEGFR and pAKT, and inhibition of cyclin D and Bcl-2 expression compared to that observed in response to BBR or erlotinib alone. The efficacy of the combination treatment was also investigated in nude mice. Consistent with the in vitro results, BBR plus erlotinib significantly reduced tumor growth.

CONCLUSION

Our data supported use of BBR in combination with erlotinib as a novel strategy for treatment of patients with EGFR positive tumors.

Continuous Vaginal Bleeding Induced By EGFR-TKI in Premenopausal Female Patients With EGFR Mutant NSCLC

EGFR-TKI is widely used for EGFR-mutant NSCLC patients. Bleeding is reported as a neglected adverse effect induced by EGFR-TKI. Female patients with lung adenocarcinoma have a high frequency of EGFR mutations. This study investigated the effect of EGFR-TKI on the menstrual cycle, especially on bleeding, in women of childbearing age. The underlying mechanism was further investigated in a patient with severe bleeding. We retrospectively investigated the effects on menstrual cycle in premenopausal female NSCLC patients who underwent EGFR-TKI treatment during 2013 to 2019. Menstrual changes including cycle disorders and prolonged bleeding were investigated via questionnaire survey. EGFR signaling, ER, PR and tissue factor expression were analyzed in endometrium tissue obtained from a 43-year-old patient who suffered from continuous vaginal bleeding during treatment with erlotinib and osimertinib. Among 42 premenopausal female patients taking EGFR tyrosine kinase inhibitor, 69.05% patients experienced abnormal menstruation. In women with abnormal menstruation, 41.37% had profuse menstruation and 20.69% had irregular menstruation. In most cases, the abnormal vaginal bleeding stopped when suspending EGFR-TKI. The EGFR-TKI induced abnormal vaginal bleeding might be associated with low progesterone level, decreased EGFR activation and tissue factor (TF) expression in endometrial tissues. EGFR-TKI unusually induce abnormal vaginal bleeding in premenopausal female NSCLC patients, which may be attributed to progesterone/EGFR/TF signaling. Megestrol acetate may be an available and effective drug for the uncommon adverse effect.

Suberoylanilide hydroxamic acid overcomes erlotinib-acquired resistance via phosphatase and tensin homolog deleted on chromosome 10-mediated apoptosis in non-small cell lung cancer

Background:

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), such as erlotinib and gefitinib, are widely used to treat non-small cell lung cancer (NSCLC). However, acquired resistance is unavoidable, impairing the anti-tumor effects of EGFR-TKIs. It is reported that histone deacetylase (HDAC) inhibitors could enhance the anti-tumor effects of other antineoplastic agents and radiotherapy. However, whether the HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) can overcome erlotinib-acquired resistance is not fully clear.

Methods:

An erlotinib-resistant PC-9/ER cell line was established through cell maintenance in a series of erlotinib-containing cultures. NSCLC cells were co-cultured with SAHA, erlotinib, or their combination, and then the viability of cells was measured by the 3-(4,5-Dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and apoptosis was determined by flow cytometry and western blotting. Finally, the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) was assessed by western blotting.

Results:

The half-maximal inhibitory concentration of parental PC-9 cells was significantly lower than the established erlotinib-acquired resistant PC-9/ER cell line. PC-9/ER cells demonstrated reduced expression of PTEN compared with PC-9 and H1975 cells, and the combination of SAHA and erlotinib significantly inhibited cell growth and increased apoptosis in both PC-9/ER and H1975 cells. Furthermore, treating PC-9/ER cells with SAHA or SAHA combined with erlotinib significantly upregulated the expression of PTEN mRNA and protein compared with erlotinib treatment alone.

Conclusions:

PTEN deletion is closely related to acquired resistance to EGFR-TKIs, and treatment with the combination of SAHA and erlotinib showed a greater inhibitory effect on NSCLC cells than single-drug therapy. SAHA enhances the suppressive effects of erlotinib in lung cancer cells, increasing cellular apoptosis and PTEN expression. SAHA can be a potential adjuvant to erlotinib treatment, and thus, can improve the efficacy of NSCLC therapy.

AlgPred 2.0: an improved method for predicting allergenic proteins and mapping of IgE epitopes

AlgPred 2.0 is a web server developed for predicting allergenic proteins and allergenic regions in a protein. It is an updated version of AlgPred developed in 2006. The dataset used for training, testing and validation consists of 10 075 allergens and 10 075 non-allergens. In addition, 10 451 experimentally validated immunoglobulin E (IgE) epitopes were used to identify antigenic regions in a protein. All models were trained on 80% of data called training dataset, and the performance of models was evaluated using 5-fold cross-validation technique. The performance of the final model trained on the training dataset was evaluated on 20% of data called validation dataset; no two proteins in any two sets have more than 40% similarity. First, a Basic Local Alignment Search Tool (BLAST) search has been performed against the dataset, and allergens were predicted based on the level of similarity with known allergens. Second, IgE epitopes obtained from the IEDB database were searched in the dataset to predict allergens based on their presence in a protein. Third, motif-based approaches like multiple EM for motif elicitation/motif alignment and search tool have been used to predict allergens. Fourth, allergen prediction models have been developed using a wide range of machine learning techniques. Finally, the ensemble approach has been used for predicting allergenic protein by combining prediction scores of different approaches. Our best model achieved maximum performance in terms of area under receiver operating characteristic curve 0.98 with Matthew's correlation coefficient 0.85 on the validation dataset. A web server AlgPred 2.0 has been developed that allows the prediction of allergens, mapping of IgE epitope, motif search and BLAST search (https://webs.iiitd.edu.in/raghava/algpred2/).

Integrated analysis of long non-coding RNAs and mRNA profiles reveals potential sex-dependent biomarkers of bevacizumab/erlotinib response in advanced lung cancer

Background

While lung cancer patient outcomes are well-recognized to vary as a function of patient sex, there has been insufficient research regarding the relationship between patient sex and EGFR(Epidermal growth factor receptor) response efficacy. The present study therefore sought to identify novel sex-related biomarkers of bevacizumab/erlotinib (BE) responses in non-small cell lung cancer (NSCLC) patients.

Methods

The exon array data in the Gene Expression Omnibus (GEO) dataset were analyzed in order to identify patterns of mRNA and lncRNA expression associated with BE resistance in NSCLC. These differentially expressed (DE) lncRNAs and mRNAs were identified via DE Analysis Filtering. These DE mRNAs were then assessed for their potential functional roles via pathway enrichment analyses, with overlapping functions possibly associated with the BE resistance. The mRNAs in these overlapping groups were then assessed for their correlations with patient survival, and lncRNA-mRNA co-expression networks were generated for each patient subset. A protein-protein interaction (PPI) network was also generated based upon these DE mRNAs.

Results

In females we identified 172 DE lncRNAs and 1766 DE mRNAs associated with BE responses, while in males we identified 78 DE lncRNAs and 485 DE mRNAs associated with such responses. Based on the overlap between these two datasets, we identified a total of 37 GO functions and 18 pathways associated with BE responses. Co-expression and PPI networks suggested that the key lncRNAs and mRNAs associated with these BE response mechanisms weredifferent in the male and female patients.

Conclusions

This work is the first to conduct a global profiling of the relationship between lncRNA and mRNA expression patterns, patient sex, and BE responses in individuals suffering from NSCLC. Together these results suggest that the integrative lncRNA-mRNA expression analyses may offer invaluable new therapeutic insights that can guide the tailored treatment of lung cancer in order to ensure optimal BE responses.

Doxazosin, a Classic Alpha 1-Adrenoceptor Antagonist, Overcomes Osimertinib Resistance in Cancer Cells via the Upregulation of Autophagy as Drug Repurposing

Osimertinib, which is a third-generation epidermal growth factor receptor tyrosine kinase inhibitor, is an important anticancer drug because of its high efficacy and excellent safety profile. However, resistance against osimertinib is inevitable; therefore, therapeutic strategies to overcome the resistance are needed. Doxazosin, a classic quinazoline-based alpha 1-adrenoceptor antagonist is used to treat hypertension and benign prostatic hyperplasia with a known safety profile. The anticancer effects of doxazosin have been examined in various types of malignancies from the viewpoint of drug repositioning or repurposing. However, it currently remains unclear whether doxazosin sensitizes cancer cells to osimertinib. Herein, we demonstrated that doxazosin induced autophagy and enhanced the anticancer effects of osimertinib on the cancer cells and cancer stem cells of non-small cell lung cancer, pancreatic cancer, and glioblastoma at a concentration at which the growth of non-tumor cells was not affected. The osimertinib-sensitizing effects of doxazosin were suppressed by 3-methyladenine, an inhibitor of autophagy, which suggested that the effects of doxazosin were mediated by autophagy. The present study provides evidence for the efficacy of doxazosin as a combination therapy with osimertinib to overcome resistance against osimertinib.

Treatment of non-small-cell lung cancer after progression on nivolumab or pembrolizumab

Background

Although PD-1 antibodies (PD1 Ab) are the standard of care for advanced non-small-cell lung cancer (ansclc), most patients will progress. We compared survival outcomes for patients with ansclc who received systemic therapy (st) after progression and for those who did not. Additionally, clinical characteristics that predicted receipt of st after PD1 Ab failure were evaluated.

Methods

All patients with ansclc in British Columbia initiated on nivolumab or pembrolizumab between June 2015 and November 2017, with subsequent progression, were identified. Eligibility criteria for additional st included an Eastern Cooperative Oncology Group (ecog) performance status (ps) of 3 or less and survival for more than 30 days from the last PD1 Ab treatment. Post-progression survival (pps) was assessed by landmark analysis. Baseline characteristics associated with pps were identified by multivariable analysis.

Results

Of 94 patients meeting the eligibility criteria, 33 received st after progression. In 75.6%, a PD1 Ab was received as first- or second-line treatment. The most common sts were erlotinib (36.4%) and docetaxel (27.3%). No statistically significant difference in median pps was observed between patients who did and did not receive st within 30 days of their last PD1 Ab treatment (6.9 months vs. 3.6 months, log-rank p = 0.15.) In multivariable analysis, factors associated with increased pps included an ecog ps of 0 or 1 compared with 2 or 3 [hazard ratio (hr): 0.42; 95% confidence interval (ci): 0.24 to 0.73; p = 0.002] and any response compared with no response to PD1 Ab (hr: 0.54; 95% ci: 0.33 to 0.90; p = 0.02).

Conclusions

In this cohort, only 35.1% of patients eligible for post-PD1 Ab therapy received st. Post-progression survival was not significantly affected by receipt of post-progression therapy. Prospective trials are needed to clarify the benefit of post-PD1 Ab treatments.

A novel diagnostic system to evaluate epidermal growth factor receptor impact as a prognostic and therapeutic indicator for lung adenocarcinoma

Many driver pathways for cancer cell proliferation have been reported. Driver pathway activation is often evaluated based on a single hotspot mutation such as EGFR L858R. However, because of complex intratumoral networks, the impact of a driver pathway cannot be predicted based on only a single gene mutation. Here, we developed a novel diagnostic system named the "EGFR impact score" which is based on multiplex mRNA expression profiles, which can predict the impact of the EGFR pathway in lung cancer cells and the effect of EGFR-tyrosine kinase inhibitors on malignancy. The EGFR impact score indicated robust predictive power for the prognosis of early-stage lung cancer because this score can evaluate the impact of the EGFR pathway on the tumor and genomic instability. Additionally, the molecular features of the poor prognostic group resembled those of biomarkers associated with immune checkpoint inhibitors. The EGFR impact score is a novel prognostic and therapeutic indicator for lung adenocarcinoma.

A Hybrid Model for Predicting Pattern Recognition Receptors Using Evolutionary Information

This study describes a method developed for predicting pattern recognition receptors (PRRs), which are an integral part of the immune system. The models developed here were trained and evaluated on the largest possible non-redundant PRRs, obtained from PRRDB 2.0, and non-pattern recognition receptors (Non-PRRs), obtained from Swiss-Prot. Firstly, a similarity-based approach using BLAST was used to predict PRRs and got limited success due to a large number of no-hits. Secondly, machine learning-based models were developed using sequence composition and achieved a maximum MCC of 0.63. In addition to this, models were developed using evolutionary information in the form of PSSM composition and achieved maximum MCC value of 0.66. Finally, we developed hybrid models that combined a similarity-based approach using BLAST and machine learning-based models. Our best model, which combined BLAST and PSSM based model, achieved a maximum MCC value of 0.82 with an AUROC value of 0.95, utilizing the potential of both similarity-based search and machine learning techniques. In order to facilitate the scientific community, we also developed a web server "PRRpred" based on the best model developed in this study (http://webs.iiitd.edu.in/raghava/prrpred/).

Predictive biomarkers for response to EGFR-directed monoclonal antibodies for advanced squamous cell lung cancer

Background

Upregulated expression and aberrant activation of the epidermal growth-factor receptor (EGFR) are found in lung cancer, making EGFR a relevant target for non-small-cell lung cancer (NSCLC). Treatment with anti-EGFR monoclonal antibodies (mAbs) is associated with modest improvement in overall survival in patients with squamous cell lung cancer (SqCLC) who have a significant unmet need for effective treatment options. While there is evidence that using EGFR gene copy number, EGFR mutation, and EGFR protein expression as biomarkers can help select patients who respond to treatment, it is important to consider biomarkers for response in patients treated with combination therapies that include EGFR mAbs.

Design

Randomized trials of EGFR-directed mAbs cetuximab and necitumumab in combination with chemotherapy, immunotherapy, or antiangiogenic therapy in patients with advanced NSCLC, including SqCLC, were searched in the literature. Results of associations of potential biomarkers and outcomes were summarized.

Results

Data from phase III clinical trials indicate that patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein (H-score of ≥200) and/or gene copy numbers of EGFR (e.g. ≥40% cells with ≥4 EGFR copies as detected by fluorescence in situ hybridization; gene amplification in ≥10% of analyzed cells) derive greater therapeutic benefits from EGFR-directed mAbs. Biomarker data are limited for EGFR mAbs used in combination with immunotherapy and are absent when used in combination with antiangiogenic agents.

Conclusions

Therapy with EGFR-directed mAbs in combination with chemotherapy is associated with greater clinical benefits in patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein and/or have increased EGFR gene copy number. These data support validating the role of these as biomarkers to identify those patients who derive the greatest clinical benefit from EGFR mAb therapy. However, data on biomarkers for EGFR-directed mAbs combined with immunotherapy or antiangiogenic agents remain limited.

Risk stratification for lung adenocarcinoma on EGFR and TP53 mutation status, chemotherapy, and PD-L1 immunotherapy

The overall survival rates for lung cancer remain unsatisfactorily low, even for patients with biomarkers for which target therapies or immunotherapies are recommended. Better identification of at‐risk patients is needed to achieve more effective personalized treatment. Here, we derived a risk‐stratifying gene signature consisting of five genes that had the greatest differential expression by stage from lung adenocarcinoma (LUAD) transcriptomes. The new gene signature enabled survival prognosis for multiple LUAD datasets from different platforms of transcriptomics and risk stratification for patients with and without a mutation in TP53 or EGFR, with high and low levels of PD‐L1, and with and without adjuvant chemotherapy treatment. Using these evaluations, it was also shown to be more robust compared to several other gene signatures. Functional analysis of the five genes and their protein‐protein interaction partners indicated that they are functionally enriched in cell cycle, endocytosis, and EGFR regulation, which are biological processes associated with lung cancer and drug resistance. Extensive discussions on related experimental studies suggest that the five genes are novel and sensible targets for developing new drugs and/or tackling drug resistance problems for LUAD.

[Second- or third-line treatment with erlotinib in EGFR wild-type non-small cell lung cancer: Real-life data]

INTRODUCTION

The benefit of tyrosine kinase inhibitors for patients with an EGFR wild-type non-small cell lung cancer (NSCLC) remains controversial.

METHODS

The survival of patients with an EGFR wild-type NSCLC who received second- or third-line erlotinib treatment was assessed using real-life data that had been collected in a prospective, national, multicenter, non-interventional cohort study.

RESULTS

Data from 274 patients were analysed, 185 (68%) treated with erlotinib and 89 (32%) treated with supportive care only. The median overall survival was 4.2months (95% CI [3.5; 5.4]) with erlotinib, and 1.3months (95% CI [1.0; 1.8]) with supportive care. Survival rate at 3, 6, and 12months was 62%, 37%, and 17%, respectively, with erlotinib, versus 20%, 8%, et 3%, with exclusive supportive care. Significant predictive factors for longer overall survival were the presence of adenocarcinoma, and use of 1st line chemotherapy including either taxanes, pemetrexed or vinorelbine (P<0.05).

CONCLUSION

Erlotinib remains a valuable therapeutic option to treat inoperable locally advanced or metastatic NSCLC after failure of at least one prior chemotherapy regimen in fragile patients who are not eligible for chemotherapy.

LncRNA DUXAP9-206 directly binds with Cbl-b to augment EGFR signaling and promotes non-small cell lung cancer progression

Long noncoding RNAs (lncRNAs) are involved in the pathology of various tumours, including non‐small cell lung cancer (NSCLC). However, the underlying molecular mechanisms of their specific association with NSCLC have not been fully elucidated. Here, we report that a cytoplasmic lncRNA, DUXAP9‐206 is overexpressed in NSCLC cells and closely related to NSCLC clinical features and poor patient survival. We reveal that DUXAP9‐206 induced NSCLC cell proliferation and metastasis by directly interacting with Cbl‐b, an E3 ubiquitin ligase, and reducing the degradation of epidermal growth factor receptor (EGFR) and thereby augmenting EGFR signaling in NSCLC. Notably, correlations between DUXAP9‐206 and activated EGFR signaling were also validated in NSCLC patient specimens. Collectively, our findings reveal the novel molecular mechanisms of DUXAP9‐206 in mediating the progression of NSCLC and DUXAP9‐206 may serve as a potential target for NSCLC therapy.

Randomized phase II study of fulvestrant and erlotinib compared with erlotinib alone in patients with advanced or metastatic non-small cell lung cancer

OBJECTIVES

This open-label, randomized phase II trial evaluated antitumor efficacy of an antiestrogen, fulvestrant, in combination with human epidermal growth factor receptor (EGFR) inhibitor, erlotinib, in advanced non-small cell lung cancer (NSCLC) patients.

MATERIALS AND METHODS

Patients with advanced or metastatic NSCLC, ECOG 0-2, previous chemotherapy unless patient refusal, and no prior EGFR-directed therapy were randomized 2:1 to erlotinib 150 mg oral daily plus 500 mg intramuscular fulvestrant on day 1, 15, 29 and every 28 days thereafter or erlotinib alone 150 mg oral daily. The primary end point was objective response rate (ORR); secondary endpoints included progression free survival (PFS) and overall survival (OS).

RESULTS

Among 106 randomized patients, 100 received at least one dose of study drug. ORR was 16.4% (11 of 67 patients) for the combination versus 12.1% (4 of 33 patients) for erlotinib (p = 0.77). PFS median 3.5 versus 1.9 months [HR = 0.86, 95% CI (0.52-1.43), p = 0.29] and OS median 9.5 versus 5.8 months [HR = 0.92, 95% CI (0.57-1.48), p = 0.74] numerically favored the combination. In an unplanned subset analysis, among EGFR wild type patients (n = 51), but not EGFR mutant patients (n = 17), median PFS was 3.5 versus 1.7 months [HR = 0.35, 95% CI (0.14-0.86), p = 0.02] and OS was 6.2 versus 5.2 months [HR = 0.72, 95% CI (0.35-1.48), p = 0.37] for combined therapy versus erlotinib, respectively. Notably, EGFR WT patients were more likely to be hormone receptor-positive (either estrogen receptor α- and/or progesterone receptor-positive) compared to EGFR mutant patients (50% versus 9.1%, respectively) (p = 0.03). Treatment was well tolerated with predominant grade 1-2 dermatologic and gastrointestinal adverse effects.

CONCLUSION

Addition of fulvestrant to erlotinib was well tolerated, with increased activity noted among EGFR wild type patients compared to erlotinib alone, albeit in an unplanned subset analysis.

Involvement of GLUT1-mediated glucose transport and metabolism in gefitinib resistance of non-small-cell lung cancer cells

Use of epidermal growth factor receptor (EGFR) inhibitors represented by gefitinib and erlotinib has become the standard of treatment for non-small-cell lung cancers (NSCLCs) with activating EGFR mutations. However, the majority of NSCLCs, which overexpress EGFR without such mutations, are resistant to EGFR inhibitors, and the mechanism(s) behind such primary resistance of NSCLCs without activating EGFR mutations to EGFR inhibitors still remains poorly understood. Here in this study, we show that glucose metabolism mediated by GLUT1, a facilitative glucose transporter, is involved in gefitinib resistance of NSCLC cells. We found that GLUT1 expression and glucose uptake were increased in resistant NSCLC cells after gefitinib treatment and that genetic as well as pharmacological inhibition of GLUT1 sensitized not only NSCLC cells with primary resistance but also those with acquired resistance to gefitinib. In vivo, the combination of systemic gefitinib and a GLUT1 inhibitor, both of which failed to inhibit tumor growth when administered alone, significantly inhibited the growth of xenograft tumors formed by the implantation of NSCLC cells with wild-type EGFR (wt-EGFR). Since our data indicated that GLUT1 was similarly involved in erlotinib resistance, our findings suggest that the activity of GLUT1-mediated glucose metabolism could be a critical determinant for the sensitivity of NSCLC cells to EGFR inhibitors and that concurrent GLUT1 inhibition may therefore be a mechanism-based approach to treating NSCLCs resistant to EGFR inhibitors, including those with wt-EGFR.

Factors that Predict Clinical Benefit of EGFR TKI Therapy in Patients with EGFR Wild-Type Lung Adenocarcinoma

Background

Epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancers have emerged as key predictive biomarkers in EGFR tyrosine kinase inhibitor (TKI) treatment. However, a few patients with wild-type EGFR also respond to EGFR TKIs. This study investigated the factors predicting successful EGFR TKI treatment in lung adenocarcinoma patients with wild-type EGFR.

Methods

We examined 66 patients diagnosed with lung adenocarcinoma carrying wide-type EGFR who were treated with EGFR TKIs. The EGFR gene copy number was assessed by silver in situ hybridization (SISH). We evaluated the clinical factors and EGFR gene copy numbers that are associated with a favorable clinical response to EGFR TKIs.

Results

The objective response rate was 12.1%, while the disease control rate was 40.9%. EGFR SISH analysis was feasible in 23 cases. Twelve patients tested EGFR SISH-positive, and 11 were EGFR SISH-negative, with no significant difference in tumor response and survival between EGFR SISH-positive and -negative patients. The overall median progression-free survival (PFS) and overall survival (OS) of 66 patients were 2.1 months and 9.7 months, respectively. Female sex and Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0–1 were independent predictors of PFS. ECOG PS 0–1 and a low tumor burden of extrathoracic metastasis were independent predictors of good OS.

Conclusion

Factors such as good PS, female sex, and low tumor burden may predict favorable outcomes following EGFR TKI therapy in patients with EGFR wild-type lung adenocarcinoma. However, EGFR gene copy number was not predictive of survival.

Aldolase A promotes proliferation and G1/S transition via the EGFR/MAPK pathway in non-small cell lung cancer

BACKGROUND

Our previous study demonstrated that aldolase A (ALDOA) is overexpressed in clinical human lung squamous cell carcinoma and that ALDOA promotes epithelial-mesenchymal transition and tumorigenesis. The present study aimed to explore the function of ALDOA in the modulation of non-small cell lung cancer (NSCLC) proliferation and cell cycle progression and the potential mechanism.

METHODS

ALDOA was knocked down by short hairpin RNA in H520 and H1299 cells. ALDOA was overexpressed with vectors carrying the full-length ALDOA sequence in H1299 and H157 cells. The proliferation capacities were assessed with immunohistochemical staining, Cell Counting Kit-8 and colony formation assays. The cell cycle distribution was examined by flow cytometry, and molecular alterations were determined by western blotting. Cell synchronization was induced with nocodazole. The stability of cyclin D1 mRNA was tested. The pyruvate kinase M2 and ALDOA protein distributions were examined. Aerobic glycolysis was evaluated with Cell Titer-Glo assay, glucose colorimetric assay and lactate colorimetric assay.

RESULTS

ALDOA knockdown inhibited the proliferation and G₁/S transition in H520 cells. Conversely, ALDOA overexpression promoted the proliferation and G₁/S transition in H157 cells. The cell cycle synchronization assay showed that ALDOA expression increased in the G₁ phase and G₁/S transition. Furthermore, ALDOA knockdown reduced cyclin D1 expression by regulating epidermal growth factor receptor/mitogen-activated protein kinase (EGFR/MAPK) pathway. Similar results were found in H1299 and H157 cells. The inhibition of mitogen-activated protein kinase kinase 1/2 prompted the nuclear distribution of ALDOA. Additionally, ALDOA knockdown reduced nuclear distribution of PKM2, the extracellular lactate and intracellular adenosine triphosphate concentrations and elevated the extracellular glucose concentration.

CONCLUSIONS

ALDOA contributed to activation of the EGFR/MAPK pathway, thus promoting cyclin D1 expression and enhancing proliferation and G₁/S transition in NSCLC. Additionally, ALDOA facilitated NSCLC aerobic glycolysis.

Erlotinib for Patients with EGFR Wild-Type Metastatic NSCLC: a Retrospective Biomarkers Analysis

Erlotinib is approved for the treatment of patients with EGFR mutation positive, metastatic NSCLC. It is also approved as second/third line therapy for EGFR mutation negative patients, but in this setting the benefit of erlotinib is modest and there is no validated biomarker for selecting EGFR wild-type patients who may benefit the most from the treatment. We retrospectively assessed EGFR and K-RAS mutational status, and EGFR, c-MET and IGF1-R expression in tumor samples of 72 patients with metastatic NSCLC treated with erlotinib after at least one prior line of chemotherapy, from 2008 to 2012. We analyzed the association between biomarkers and outcome (RR, PFS, and OS). EGFR mutated patients achieved a better RR (56% vs 8%, p = .002), PFS (10 vs 3 months, HR 0.53, p = 0.48) and OS (20 vs 6 months, HR 0.55, p = .07), compared to EGFR wild-type patients. Among 63 EGFR wild-type patients, those with EGFR high-expression had a better outcome in terms of RR (40% vs 2%, p = .002), PFS (7.5 vs 2 months, HR 0.45, p = .007) and OS (30 vs 5 months, HR 0.34, p < .001) compared to patients with EGFR intermediate or low/negative-expression. IGF1-R expression, c-MET expression and K-RAS mutational status did not significantly affect the outcome; however, no patients with K-RAS mutation or c-MET high-expression achieved an objective response. In patients with metastatic, chemo-refractory EGFR wild-type NSCLC, EGFR high-expression may represent a positive predictor of activity for erlotinib, whereas K-RAS mutation and c-MET high-expression may predict lack of activity. These findings deserve further prospective evaluation.

Prognostic significance of epidermal growth factor receptor expression in glioma patients

Purpose

There is a great controversy regarding the prognostic significance of epidermal growth factor receptor (EGFR) in glioma patients. The current meta-analysis was conducted to evaluate the effect of abnormal EGFR expression on overall survival in glioma patients.

Materials and methods

A comprehensive literature search of PubMed, EMBASE, Google Scholar, Web of Science, and Cochrane Library was conducted. The combined hazard ratio (HR) and its 95% confidence intervals (CIs) were used to evaluate the association between EGFR expression and survival in glioma.

Results

A total of 476 articles were screened, and 17 articles containing 1,458 patients were selected. The quality assessment of the included studies was performed by the Newcastle-Ottawa Scale. Overexpression of EGFR was found to be an indicator of poor prognosis in overall survival in glioma patients (HR =1.72, 95% CI 1.32-2.25, P=0.000, random effect) and glioblastoma multiforme patients (HR =1.57, 95% CI 1.15-2.14, P=0.004, random effect). Subgroup analysis was conducted to explore the source of high heterogeneity.

Conclusion

This meta-analysis indicated that high expression of EGFR may serve as a biomarker for poor prognosis in glioma patients.

Polymorphisms in genes related to epithelial-mesenchymal transition and risk of non-small cell lung cancer

The epithelial-mesenchymal transition (EMT) process is a crucial step for tumor invasion and metastasis. Previous research investigating EMT has mostly focused on its role in cancer progression. Recent studies showed that EMT and EMT-driving transcription factor (EMT-TF) expression are early events in lung cancer pathogenesis, implying a potential association between EMT and lung cancer risk. In this study, we examined whether genetic variants in EMT-related genes are associated with risk of non-small cell lung cancer (NSCLC). We used data from a genome-wide association study of 1482 NSCLC cases and 1544 healthy controls as the discovery phase, in which we analyzed 1602 single-nucleotide polymorphisms (SNPs) within 159 EMT-related genes. We then validated the significant SNPs in another 5699 cases and 5815 controls from the National Cancer Institute lung cancer genome-wide association study. Cumulative effects were evaluated for validated SNPs, and a gene-based test was performed to explore gene-level association with disease risk. In the discovery phase, 174 SNPs demonstrated significant associations with NSCLC risk. In the validation phase, seven SNPs mapped to EGFR, NOTCH3, ADGRF1 and SMAD3 were confirmed. Cumulative effect analysis of the significant SNPs demonstrated increasing risk with the number of unfavorable genotypes in the discovery and validation datasets. Gene-based analysis implicated ADGRF1, NOTCH3 and CDH1 as significant for NSCLC risk. Functional prediction revealed several potential mechanisms underlying these associations. Our results suggest that EMT-related gene variants may be involved in susceptibility to NSCLC; if confirmed, they might help identify higher-risk individuals.

Which treatment is preferred for advanced non-small-cell lung cancer with wild-type epidermal growth factor receptor in second-line therapy? A meta-analysis comparing immune checkpoint inhibitor, tyrosine kinase inhibitor and chemotherapy

BACKGROUND

The recommendations regarding the optimum treatment for advanced non-small-cell lung cancer (NSCLC) patients with wild-type (WT) epidermal growth factor receptor (EGFR) tumors remain unclear. This meta-analysis was conducted to assess the efficacy among programmed death-ligand 1 (PD-L1)/programmed death-1 (PD-1) antibody, EGFR-tyrosine kinase inhibitors (TKI) and chemotherapy in second-and third-line therapy.

PATIENTS AND METHODS

Randomized trials investigating two of the three treatments were searched and included. Multiple treatments comparison and pairwise comparison were performed to assess overall survival (OS) and progression-free survival (PFS), expressed as hazard ratios (HRs). The effect of prespecified study-level characteristics was assessed by subgroup analysis and meta-regression.

RESULTS

12 randomized trials accruing 3341 advanced patients with WT EGFR tumors were analyzed. PD-1/PD-L1 antibody was associated with significantly longer OS and PFS than chemotherapy (OS: HR 0.67, 95% CrI 0.60-0.75; PFS: HR 0.83, 95% CrI 0.73-0.95) and TKI (OS: HR 0.59, 95% CrI 0.50-0.70; PFS: HR 0.75, 95% CrI 0.66-0.84) , while chemotherapy was associated with significantly longer OS (HR 0.88, 95% CrI 0.77-0.99) and PFS (HR 0.75, 95% CrI 0.66-0.84) than TKI.

CONCLUSIONS

For advanced NSCLC patients with WT-EGFR tumors in second- or third-line therapy, PD-1/PD-L1 antibody appeared to be the most efficacious treatment, which was followed by chemotherapy. EGFR-TKI was worse than chemotherapy.

The Efficacy of Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Non-Small Cell Lung Cancer Harboring Wild-type Epidermal Growth Factor Receptor: A Meta-analysis of 25 RCTs

OBJECTIVE

To determine the efficacy of first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in advanced non-small cell lung cancer (NSCLC) patients with wild-type (WT) EGFR tumors, we performed an indirect meta-analysis to assess the treatment effects of EGFR-TKIs in such patients.

METHODS

We searched for randomized controlled trials in Medline, Embase, the Cochrane controlled trials register, the Science Citation Index, and the American Society of Clinical Oncology annual meetings. Effect measures used were hazard ratios (HR) for progression-free survival (PFS) and overall survival.

RESULTS

Out of 2134 retrieved articles, 25 randomized controlled trials including more than 4467 patients were identified. This pooled analysis showed the inferior efficacy of TKI over chemotherapy among patients with WT EGFR NSCLC in terms of PFS (HR, 1.37; 95% confidence interval [CI]: 1.10, 1.72; P=0.006). When used as first-line treatment, TKIs have also fared worse than chemotherapy when compared with standard platinum doublet regimens in patients with WT EGFR in terms of PFS (HR, 2.15; 95% CI: 1.68, 2.76; P<0.001). And, the same inferior trend was found with TKIs in those trials of second-line/third-line treatment in terms of PFS (HR, 1.35; 95% CI: 1.13, 1.61; P<0.001). However, according to the pooled results, EGFR-TKIs still produced a reduction of 19% in the risk of progression over placebo in such WT EGFR patients ineligible for further chemotherapy (HR, 0.81; 95% CI: 0.68, 0.97; P=0.02). Furthermore, addition of EGFR-TKI to chemotherapy resulted in an improvement of PFS over chemotherapy alone (HR, 0.83; 95% CI: 0.71, 0.96; P=0.01).

CONCLUSIONS

Among patients with advanced NSCLC harboring WT EGFR, EGFR-TKIs were inferior to standard chemotherapy both for first-line treatment and for second-line/third-line treatment, but still superior to placebo in patients unfit for further chemotherapy. And, addition of EGFR-TKIs to chemotherapy could provide additive benefit over chemotherapy alone in such patients.

Efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in targeted therapy of lung squamous cell carcinoma patients with EGFR mutation: a pooled analysis

PURPOSE

This pooled analysis aims to evaluate the efficacy of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in lung squamous cell carcinoma with EGFR mutation.

METHODS

Advanced stage (IIIB/IV) lung squamous cell carcinoma patients with EGFR mutations treated with EGFR-TKIs were extracted from the publications searched from the databases of EMBASE, Medline (Ovid SP), Web of Science, Cochrane library, PubMed Publisher, ASCO meeting abstract and Google Scholar before August 2016, or identified from the database of Shanghai Chest Hospital from July 2014 to August 2016. Pooled objective response rate, disease control rate and median progression-free survival were accessed directly or by Kaplan-Meier method and combined in different studies by Comprehensive Meta Analysis software via one-group dichotomous or continuous analysis functions.

RESULTS

The combined objective response rate, disease control rate and median progression-free survival were 31.6% (95%CI, 24.1%∼40.2%), 72.0% (95% CI, 63.5%∼79.2%) and 3.08 months (95% CI, 2.31-3.84 months) in lung squamous cell carcinoma patients with EGFR mutation.

CONCLUSION

The EGFR-TKIs had a modest response for EGFR mutated lung squamous cell carcinoma patients and might be a selective option for those patients.

Pemetrexed-carboplatin with intercalated icotinib in the treatment of patient with advanced EGFR wild-type lung adenocarcinoma: A case report

RATIONALE

Tyrosine kinase inhibitors (TKIs) are known to have greater efficacy in epidermal growth factor receptor (EGFR) mutation nonsmall cell lung cancer (NSCLC). However, about 10% of EGFR wild-type (wt) patients respond to TKIs.

PATIENT CONCERNS

Several strategies to increase the efficacy of TKIs in wt NSCLC are the subjects of ongoing investigations. One of them is combining EGFR TKI with intercalated chemotherapy.

DIAGNOSES

We describe a patient with EGFR wt NSCLC, who was found with ovarian and lung metastasis, was treated with pemetrexed and intercalated icotinib.

INTERVENTIONS

In this case, we reported the successful long-term maintenance treatment of a patient with EGFR wt NSCLC with pemetrexed and Icotinib. The patient (40-year-old female) was found with ovarian masses and lung masses. Pathological, immunohistochemical, and amplification refractory mutation system (ARMS) assay examinations of ovarian specimen suggested the expression of metastatic lung adenocarcinoma with wt EGFR. After failure treatment with paclitaxel-carboplatin, the patient received 4 cycles of pemetrexed plus platinum with intercalated icotinib and then remained on pemetrexed and icotinib.

OUTCOMES

A partial response was achieved after the treatment. The patient's condition had remained stable on pemetrexed and icotinib for more than 20 months, with no evidence of progression.

LESSONS

To our knowledge, this is the first report using the long-term maintenance treatment with pemetrexed and intercalated icotinib in EGFR wt patient. The therapeutic strategies warrant further exploration in selected populations of NSCLC.

The Clinical and Economic Impact of Inaccurate EGFR Mutation Tests in the Treatment of Metastatic Non-Small Cell Lung Cancer

Advances in personalized medicine are supported by companion diagnostic molecular tests. Testing accuracy is critical for selecting patients for optimal therapy and reducing treatment-related toxicity. We assessed the clinical and economic impact of inaccurate test results between laboratory developed tests (LDTs) and a US Food and Drug Administration (FDA)-approved test for detection of epidermal growth factor receptor (EGFR) mutations. Using a hypothetical US cohort of newly diagnosed metastatic non-small cell lung cancer (NSCLC) patients and EURTAC (erlotinib versus standard chemotherapy as first-line treatment for European patients with advanced EGFR mutation-positive non-small-cell lung cancer) clinical trial data, we developed a decision analytic model to estimate the probability of misclassification with LDTs compared to a FDA-approved test. We estimated the clinical and economic impact of inaccurate test results by quantifying progression-free and quality-adjusted progression-free life years (PFLYs, QAPFLYs) lost, and costs due to incorrect treatment. The base-case analysis estimated 2.3% (n = 1422) of 60,502 newly diagnosed metastatic NSCLC patients would be misclassified with LDTs compared to 1% (n = 577) with a FDA-approved test. An average of 477 and 194 PFLYs were lost among the misclassified patients tested with LDTs compared to the FDA-approved test, respectively. Aggregate treatment costs for patients tested with LDTs were approximately $7.3 million more than with the FDA-approved test, due to higher drug and adverse event costs among patients incorrectly treated with targeted therapy or chemotherapy, respectively. Invalid tests contributed to greater probability of patient misclassification and incorrect therapy. In conclusion, risks associated with inaccurate EGFR mutation tests pose marked clinical and economic consequences to society. Utilization of molecular diagnostic tests with demonstrated accuracy could help to maximize the potential of personalized medicine.

Evaluation of erlotinib for the treatment of patients with non-small cell lung cancer with epidermal growth factor receptor wild type

Erlotinib is one of the treatment choices for patients with advanced non-small cell lung cancer (NSCLC), regardless of the epidermal growth factor receptor (EGFR) mutation status. However, its efficacy for the treatment of patients with NSCLC with EGFR wild type or who are beyond the usage of gefitinib remains controversial. The present study therefore retrospectively assessed the efficacy of erlotinib in patients with wild type EGFR who had previously undergone gefitinib therapy. A total of 222 patients with NSCLC who received chemotherapeutic treatment with erlotinib between July 2007 and February 2013 were evaluated. The background variables, response rates, progression-free survival (PFS) and overall survival rates were retrospectively analyzed. The male/female ratio of patients was 103/119, and patients had a median age of 63 years (range, 33-95 years). A total of 10 of the 222 patients had clinical stages IIIB/IV, 191 had adenocarcinoma, 5 had large cell carcinoma, 10 had squamous cell carcinoma and 6 had NSCLC of a variety not otherwise specified. The EGFR mutation was positive, wild type or unknown in 95, 52 and 75 patients, respectively. In the 52 patients with EGFR wild type, there were 3 partial responders, 25 with stable disease and 24 with progressive disease, for a response rate of 6% [95% confidence interval (CI), 1.3-15%]. The median PFS of EGFR wild type and positive were 1.1 months (95% CI, 1.04-1.16 months) and 5.42 months (95% CI, 5.43-5.68 months), respectively. The results of the study demonstrated that erlotinib is not sufficiently effective for patients with NSCLC who possess the EGFR wild type status.

A randomized phase III study of combining erlotinib with bevacizumab and panitumumab versus erlotinib alone as second-line therapy for Chinese patients with non-small-cell lung cancer

PURPOSE

In this phase III clinical study, we assessed the clinical outcomes of combining erlotinib with bevacizumab and panitumumab as second-line chemotherapy for patients with non-small-cell lung cancer (NSCLC).

METHODS

Chinese NSCLC patients, who received first-line platinum-based chemotherapy but still experienced disease progression, were assigned to receive second-line treatment of erlotinib plus bevacizumab and panitumumab (arm I), or erlotinib plus placebo (arm II). The primary endpoint was progression-free survival (PFS). The secondary endpoints were overall survival (OS) and response rates.

RESULTS

150 patients were enrolled in arm I, and 147 in arm II. Median PFS of arm I was 4.6 months (95% CI, 2.3-9.4 months), much longer than the median PFS in arm II (1.9 months, 95% CI 0.8-5.2 months) (P=0.003). The median OS of arm I was 10.4 months (95% CI, 7.5-13.1 months), also significantly longer than the median OS in arm II (8.9 months, 95% CI 3.3-10.9 months) (P=0.031). Partial response in arm I was 38%, significantly higher than the partial response rate of 15% in arm II (P=0.014). The occurrence rates of adverse events, including diarrhea, fatigue and rash, were higher in arm I than in arm II.

CONCLUSIONS

Erlotinib plus bevacizumab and panitumumab is an efficient second-line treatment option for patients with NSCLC.

The Efficacy of Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors for Molecularly Selected Patients with Non-Small Cell Lung Cancer: A Meta-Analysis of 30 Randomized Controlled Trials

OBJECTIVE

To determine the efficacy of first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in molecularly selected patients with advanced non-small cell lung cancer (NSCLC), we performed this pooled analysis.

METHOD

Randomized trials of EGFR-TKIs as treatment for advanced NSCLC were included for this meta-analysis. We used published hazard ratios (HRs), if available, or derived treatment estimates from other survival data. Pooled estimates of treatment efficacy of EGFR-TKIs in the selected patients by EGFR-mutation status were calculated.

RESULTS

Out of 2134 retrieved articles, 30 randomized controlled trials (RCTs) enrolling more than 4053 patients with wild-type EGFR tumors and 1592 patients with mutant EGFR tumors were identified. For EGFR mutant patients, EGFR-TKIs treatment improved progression-free survival (PFS) compared with chemotherapy: the summary HRs were 0.41 (p < 0.00001) for the first-line setting and 0.46 (p = 0.02) for second/third-line setting, respectively. Also, the same superior trend was found with TKIs maintenance over placebo (HR = 0.14, p < 0.00001) and with TKIs combined with chemotherapy over chemotherapy (HR = 0.49, p = .002) in both the first-line and maintenance therapy settings. For EGFR wild-type patients, EGFR-TKIs have fared worse than chemotherapy in the first-line setting (HR = 1.65, p = .03) and in the second/third-line setting (HR = 1.27, p = .005). However, EGFR-TKIs maintenance still produced a reduction of 19 % in the risk of progression over placebo (HR = 0.81, p = .02). Furthermore, EGFR-TKIs added to chemotherapy as first-line treatment resulted in an improvement of PFS over chemotherapy alone in such wild-type EGFR patients (HR = 0.82, p = .03). In overall survival (OS) analysis, only EGFR-TKIs single agent was inferior to chemotherapy in EGFR wild-type patients (HR = 1.13, p = .02). No statistically significant difference in terms of OS was observed in any other subgroup analysis.

CONCLUSIONS

For EGFR mutant patients, EGFR-TKIs therapy produced a prominent PFS benefit in all settings. Among EGFR wild-type patients, EGFR-TKIs were inferior to chemotherapy both for first-line treatment and for second/third-line treatment. However, EGFR-TKIs maintenance and addition of EGFR-TKIs to chemotherapy could provide additive benefit over chemotherapy alone in such EGFR wild-type patients.

DUOX1 silencing in lung cancer promotes EMT, cancer stem cell characteristics and invasive properties

Dual oxidase 1 (DUOX1) is an oxidant-generating enzyme within the airway epithelium that participates in innate airway host defense and epithelial homeostasis. Recent studies indicate that DUOX1 is suppressed in lung cancers by epigenetic silencing, although the importance of DUOX1 silencing in lung cancer development or progression is unknown. Here we show that loss of DUOX1 expression in a panel of lung cancer cell lines is strongly associated with loss of the epithelial marker E-cadherin. Moreover, RNAi-mediated DUOX1 silencing in lung epithelial cells and the cancer cell line NCI-H292 was found to result in loss of epithelial characteristics/molecular features (altered morphology, reduced barrier function and loss of E-cadherin) and increased mesenchymal features (increased migration, anchorage-independent growth and gain of vimentin/collagen), suggesting a direct contribution of DUOX1 silencing to epithelial-to-mesenchymal transition (EMT), an important feature of metastatic cancer. Conversely, overexpression of DUOX1 in A549 cells was capable of reversing EMT features. DUOX1 silencing in H292 cells also led to enhanced resistance to epidermal growth factor receptor tyrosine kinase inhibitors such as erlotinib, and enhanced levels of cancer stem cell (CSC) markers CD133 and ALDH1. Furthermore, acquired resistance of H292 cells to erlotinib resulted in enhanced EMT and CSC features, as well as loss of DUOX1. Finally, compared with control H292 cells, H292-shDUOX1 cells displayed enhanced invasive features in vitro and in vivo. Collectively, our findings indicate that DUOX1 silencing in lung epithelial cancer cells promotes features of EMT, and may be strongly associated with invasive and metastatic lung cancer.

A decade of EGFR inhibition in EGFR-mutated non small cell lung cancer (NSCLC): Old successes and future perspectives

The discovery of Epidermal Growth Factor Receptor (EGFR) mutations in Non Small Cell Lung Cancer (NSCLC) launched the era of personalized medicine in advanced NSCLC, leading to a dramatic shift in the therapeutic landscape of this disease. After ten years from the individuation of activating mutations in the tyrosine kinase domain of the EGFR in NSCLC patients responding to the EGFR tyrosine kinase inhibitor (TKI) Gefitinib, several progresses have been done and first line treatment with EGFR TKIs is a firmly established option in advanced EGFR-mutated NSCLC patients. During the last decade, different EGFR TKIs have been developed and three inhibitors have been approved so far in these selected patients. However, despite great breakthroughs have been made, treatment of these molecularly selected patients poses novel therapeutic challenges, such as emerging of acquired resistance, brain metastases development or the need to translate these treatments in earlier clinical settings, such as adjuvant therapy.

The aim of this paper is to provide a comprehensive review of the major progresses reported so far in the EGFR inhibition in this molecularly-selected subgroup of NSCLC patients, from the early successes with first generation EGFR TKIs, Erlotinib and Gefitinib, to the novel irreversible and mutant-selective inhibitors and ultimately the emerging challenges that we, in the next future, are called to deal with.

Efficacy and safety of icotinib in patients with brain metastases from lung adenocarcinoma

OBJECTIVE

The objective of this study was to evaluate the efficacy and safety of icotinib in patients with brain metastases (BMs) from lung adenocarcinoma.

PATIENTS AND METHODS

Clinical data of 28 cases with BMs from lung adenocarcinoma were retrospectively analyzed. All the patients took 125 mg icotinib orally three times a day. Progression of disease, intolerable adverse reactions, and number of deaths were recorded.

RESULTS

For all the patients, the remission rate of icotinib was 67.8% and the disease control rate was 96.4%. The median overall survival time of patients was 21.2 months, and the median progression-free survival time of patients was 10.9 months. Only mild adverse events of grade 1/2 were observed during the treatment.

CONCLUSION

Icotinib was an effective and safe strategy to treat patients with BMs from lung adenocarcinoma.

A Potent Derivative of Indolizino[6,7-b]Indole for Treatment of Human Non-Small Cell Lung Cancer Cells

The therapeutic effect in non–small cell lung cancer (NSCLC) patients is limited because of intrinsic and acquired resistance. Thus, an unmet need exists for the development of new drugs to improve the therapeutic efficacy in NSCLC patients. In this study, the novel small molecule indolizino[6,7-b]indole derivative BO-1978 was selected to evaluate its therapeutic effects on NSCLC and its preclinical toxicity in animal models. An in vitro cytotoxicity assay revealed that BO-1978 significantly suppressed the growth of various NSCLC cell lines with or without mutations in epidermal growth factor receptor (EGFR). Mechanistically, we demonstrated that BO-1978 exhibited multiple modes of action, including inhibition of topoisomerase I/II and induction of DNA cross-linking. Treatment of NSCLC cells with BO-1978 caused DNA damage, disturbed cell cycle progression, and triggered apoptotic cell death. Furthermore, BO-1978 significantly suppressed the growth of EGFR wild-type and mutant NSCLC tumors in xenograft tumor and orthotopic lung tumor models with negligible body weight loss. The combination of BO-1978 with gefitinib further suppressed EGFR mutant NSCLC cell growth in xenograft tumor and orthotopic lung tumor models. Preclinical toxicity studies showed that BO-1978 administration did not cause apparent toxicity in mice. Based on its significant therapeutic efficacy and low drug toxicity, BO-1978 is a potential therapeutic agent for treatment of NSCLC.

Epidermal Growth Factor Receptor Inhibition in the Management of Squamous Cell Carcinoma of the Lung

Molecular therapies targeting epidermal growth factor receptor (EGFR) have had a profound impact on the management of advanced non-small cell lung cancer (NSCLC). EGFR inhibition with EGFR tyrosine kinase inhibitors (EGFR-TKIs) and anti-EGFR monoclonal antibodies (mAbs) in squamous NSCLC (sqNSCLC) remains controversial in patients whose tumors are not known to harbor EGFR mutations. Recent meta-analyses of EGFR-inhibition randomized trials that are adequately powered for histological subgroup analysis and anti-EGFR trials limited to patients with squamous histology afford the opportunity to revisit EGFR treatment in sqNSCLC. In unselected patients with sqNSCLC who are not eligible for chemotherapy, EGFR-TKI therapy is a valid treatment option over placebo or best supportive care, with improved progression-free survival noted in randomized controlled trials in both the first- and second-line setting and improved overall survival (OS) in the second-line setting. In patients eligible for chemotherapy, first-line combination regimens with anti-EGFR mAbs have been shown to improve OS over chemotherapy alone in patients with squamous histology in meta-analysis and more recently in the SQUIRE sqNSCLC trial (chemotherapy with and without necitumumab). In sqNSCLC patients who respond to induction chemotherapy, maintenance therapy with erlotinib delays disease progression and may improve the survival of patients with stable disease. In the second-line setting, survival outcomes are comparable between chemotherapy and EGFR-TKIs in meta-analysis, with the latter being more tolerable as a second-line therapy. Newer-generation EGFR-TKI therapies may further benefit patients with sqNSCLC who have failed first-line chemotherapy, given the positive trial results from LUX-Lung 8 (afatinib vs. erlotinib). EGFR is a valid therapeutic target in unselected/EGFR wild-type patients with squamous cell carcinoma of the lung. With the recent approval of immune checkpoint inhibitors in the second-line management of advanced sqNSCLC and their adoption as a new standard of care, there exists an opportunity for novel combination therapies to increase therapeutic efficacy and durable tumor control. As more targeted agents are approved, combination regimens that include an anti-EGFR agent should be evaluated, and the optimal sequencing of targeted therapies should be defined.

IMPLICATIONS FOR PRACTICE

Anti-epidermal growth factor receptor (EGFR) therapies remain controversial in unselected/wild-type EGFR squamous non-small cell lung cancer (NSCLC). Recent meta-analyses and squamous-only NSCLC EGFR-inhibition trials have overcome the power limitations of early trials and can now inform the management of squamous NSCLC with anti-EGFR therapies. With the approval of immunotherapeutics in the second-line management of squamous NSCLC, there exists an opportunity for novel combination therapies to improve efficacy and durable tumor control. The optimal timing and sequencing of available second-line targeted therapies, however, have yet to be defined. This review analyzes randomized clinical trials of EGFR inhibition in NSCLC and meta-analyses of these trials, with a focus on patients with squamous histology.

Epidermal growth factor receptor tyrosine kinase inhibitors in previously treated advanced non-small-cell lung cancer with wild-type EGFR

INTRODUCTION

While epidermal growth factor receptor (EGFR) - tyrosine kinase inhibitors (TKIs) lead to longer progression-free survival (PFS) when compared with conventional chemotherapy in non-small-cell lung cancer (NSCLC) harboring activating EGFR mutations, the role of EGFR-TKI remains unclear in EGFR-wild-type (WT) NSCLC.

AREAS COVERED

This article reviews selected data from randomized trials regarding the use of TKIs in EGFR-WT NSCLC. Nine randomized phase III trials have compared EGFR-TKI with chemotherapy in NSCLC patients in a second or later line setting. Two of these trials, TAILOR and DELTA, which were designed to investigate treatment benefits according to EGFR genotype, demonstrated that docetaxel chemotherapy displayed significantly better in progression-free survival (PFS) when compared with the EGFR-TKI erlotinib. Biomarkers to predict clinical benefits of the drug against EGFR WT tumor, and the efficacy of combination regimens using erlotinib or single-use afatinib against tumors are also covered in this article.

EXPERT OPINION

Considering the modest benefits of erlotinib for EGFR-WT tumors, future studies are warranted, including the exploration of useful biomarkers and new treatment strategies for EGFT-TKI use, as well as the development of more sensitive EGFR mutation tests.

Computational discovery of pathway-level genetic vulnerabilities in non-small-cell lung cancer

Motivation: Novel approaches are needed for discovery of targeted therapies for non-small-cell lung cancer (NSCLC) that are specific to certain patients. Whole genome RNAi screening of lung cancer cell lines provides an ideal source for determining candidate drug targets.

Results: Unsupervised learning algorithms uncovered patterns of differential vulnerability across lung cancer cell lines to loss of functionally related genes. Such genetic vulnerabilities represent candidate targets for therapy and are found to be involved in splicing, translation and protein folding. In particular, many NSCLC cell lines were especially sensitive to the loss of components of the LSm2-8 protein complex or the CCT/TRiC chaperonin. Different vulnerabilities were also found for different cell line subgroups. Furthermore, the predicted vulnerability of a single adenocarcinoma cell line to loss of the Wnt pathway was experimentally validated with screening of small-molecule Wnt inhibitors against an extensive cell line panel.

Availability and implementation: The clustering algorithm is implemented in Python and is freely available at https://bitbucket.org/youngjh/nsclc_paper.

Contact:marcotte@icmb.utexas.edu or jon.young@utexas.edu

Supplementary information:Supplementary data are available at Bioinformatics online.

Elderly male smokers with right lung tumors are viable candidates for KRAS mutation screening

Genetic aberrations in tumor driver genes provide specific molecular targets for therapeutic intervention, which can greatly improve therapeutic outcomes. Here, we analyzed the mutational frequency of EGFR and KRAS gene, as well as EML4-ALK rearrangement, and summarized the clinicopathological characters of Chinese lung cancer patients. We detected the mutation spectrum of 1033 primary lung cancer patients. The analyzed clinicopathological parameters included gender, age at diagnosis, smoking status, pathological TNM stage, tumor morphology and location, visceral pleural invasion, and histological type. A total of 618 patients had mutations in EGFR or KRAS gene as well as rearrangement of EML4-ALK. Exon 19 deletions and L858R in the EGFR gene were the most frequent mutations. Left-side lung cancer was more common in female patients carrying the KRAS mutation. Rearrangement of EML4-ALK was more common in non-tobacco-using male patients, who also exhibited a higher likelihood of visceral pleura invasion. Elderly females who never smoked and possessed 1–20 mm stage I adenocarcinomas in the right side exhibited a higher frequency of EGFR mutations. Elderly male smokers with right lung tumors were viable candidates for KRAS mutation screening.

Vorinostat synergizes with EGFR inhibitors in NSCLC cells by increasing ROS via up-regulation of the major mitochondrial porin VDAC1 and modulation of the c-Myc-NRF2-KEAP1 pathway

In non-small-cell lung cancer (NSCLC) patients, the activation of alternative pathways contributes to the limited efficacy of the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) gefitinib and erlotinib. The present study examines a panel of EGFR wild-type, K-Ras mutated, NSCLC lines, which were all intrinsically resistant to EGFR-TKIs, and demonstrates that the histone deacetylase inhibitor vorinostat can improve the therapeutic efficacy of gefitinib or erlotinib, inducing strong synergistic antiproliferative and pro-apoptotic effects that are paralleled by reactive oxygen species accumulation and by increased DNA damage. By knockdown experiments, we suggested that the up-regulation of voltage-dependent anion-selective channel protein 1 (VDAC1), the major mitochondrial porin of the outer mitochondrial membrane, which was induced by vorinostat and further increased by the combination, could be functionally involved in oxidative stress-dependent apoptosis. Significantly, we also observed the attenuation of the expression of both the enzyme hexokinase1, a negative VDAC1 regulator, and the anti-apoptotic porin VDAC2, only in the combination setting, suggesting convergent mechanisms that enhanced mitochondria-dependent apoptosis by targeting VDAC protein functions. Furthermore, the prosurvival capacities of the cells were also inhibited by the combination treatments, as shown by complete pAKT deactivation, increased GSK3β expression, and c-Myc down-regulation. Finally, we observed that the combination treatment of vorinostat and either of the EGFR-TKIs induced the down-regulation of the c-Myc-regulated nuclear factor erythroid 2-related factor 2 (NRF2) transcription factor and the up-regulation of the NRF2 repressor Kelch-like ECH-associated protein 1 regulator (KEAP1). These two genes are crucial for the redox stress response, often dysfunctional in NSCLC, and involved in EGFR-TKI resistance. Taken together, these results are the first to demonstrate that altering redox homeostasis is a new mechanism underlying the observed synergism between vorinostat and EGFR TKIs in NSCLC.

Comparison of the Efficacy between Pemetrexed plus Platinum and Non-Pemetrexed plus Platinum as First-Line Treatment in Patients with Wild-Type Epidermal Growth Factor Receptor Nonsquamous Non-Small Cell Lung Cancer: A Retrospective Analysis

Background: Despite the development of molecular research and targeted therapy, patients with wild-type epidermal growth factor receptor (EGFR) non-small cell lung cancer (NSCLC) still receive platinum doublet chemotherapy as the standard first-line treatment. We investigated the efficacy of first-line regimens in patients with wild-type EGFR nonsquamous NSCLC. Methods: We retrospectively analyzed the efficacy of various platinum doublet regimens as first-line treatments. Between 2007 and 2013, a total of 165 patients with wild-type EGFR nonsquamous NSCLC were included in this study. Results: Seventy-one (43.0%) patients were treated with pemetrexed plus platinum (PP) and 94 (57.0%) with non-pemetrexed plus platinum (NPP). The overall response rate was not different between the PP- and NPP-treated groups (26.8 vs. 28.7%, respectively; p = 0.78). The median progression-free survival (PFS) and overall survival (OS) also showed no differences between the two treatment groups (p = 0.12 for PFS, p = 0.42 for OS). The median PFS and OS for the PP group were 4.6 months (95% CI, 3.8-5.4) and 18.7 months (95% CI, 11.7-25.8), respectively, and for the NPP group, they were 4.2 months (95% CI, 3.4-5.0) and 12.2 months (95% CI, 10.3-14.1), respectively. In the subgroup analysis, most subgroups showed no significant difference in PFS and OS between the two treatment groups. Conclusion: Our data showed that the efficacy of various platinum doublet regimens was similar in patients with wild-type EGFR nonsquamous NSCLC.

EGFR gene-mutation status correlated with therapeutic decision making in lung adenocarcinoma

The purpose of this study was to investigate the correlation between EGFR-mutation status and treatment efficacy for advanced lung adenocarcinoma patients. A total of 47 patients receiving erlotinib as first-line therapy were divided into two groups: the EGFR gene mutation group included 19 patients with known EGFR-sensitive mutations, and the EGFR-mutation status-unknown group comprised 28 patients with unknown EGFR-mutation status. Both objective response rate and disease-control rate were significantly higher in the EGFR-mutation group compared with the EGFR-unknown group (42.1% vs 14.2%, P=0.032; 94.7% vs 57.1%, P=0.005). Age, sex, smoking history, stage of disease, and tissue-sample source were not significantly correlated with the distributions of mutation status. In conclusion, it is important for advanced lung adenocarcinoma patients to undergo gene analysis before being assigned a molecularly targeted drug as first-line treatment.

Tyr1068-phosphorylated epidermal growth factor receptor (EGFR) predicts cancer stem cell targeting by erlotinib in preclinical models of wild-type EGFR lung cancer

Tyrosine kinase inhibitors (TKIs) have shown strong activity against non-small-cell lung cancer (NSCLC) patients harboring activating epidermal growth factor receptor (EGFR) mutations. However, a fraction of EGFR wild-type (WT) patients may have an improvement in terms of response rate and progression-free survival when treated with erlotinib, suggesting that factors other than EGFR mutation may lead to TKI sensitivity. However, at present, no sufficiently robust clinical or biological parameters have been defined to identify WT-EGFR patients with greater chances of response. Therapeutics validation has necessarily to focus on lung cancer stem cells (LCSCs) as they are more difficult to eradicate and represent the tumor-maintaining cell population. Here, we investigated erlotinib response of lung CSCs with WT-EGFR and identified EGFR phosphorylation at tyrosine1068 (EGFRtyr1068) as a powerful biomarker associated with erlotinib sensitivity both in vitro and in preclinical CSC-generated xenografts. In contrast to the preferential cytotoxicity of chemotherapy against the more differentiated cells, in EGFRtyr1068 cells, erlotinib was even more active against the LCSCs compared with their differentiated counterpart, acquiring potential value as CSC-directed therapeutics in the context of WT-EGFR lung cancer. Although tumor growth was inhibited to a similar extent during erlotinib or chemotherapy administration to responsive tumors, erlotinib proved superior to chemotherapy in terms of higher tolerability and reduced tumor aggressiveness after treatment suspension, substantiating the possibility of preferential LCSC targeting, both in adenocarcinoma (ADC) and squamous cell carcinoma (SCC) tumors. We conclude that EGFRtyr1068 may represent a potential candidate biomarker predicting erlotinib response at CSC-level in EGFR-WT lung cancer patients. Finally, besides its invariable association with erlotinib sensitivity in EGFR-WT lung CSCs, EGFRtyr1068 was associated with EGFR-sensitizing mutations in cell lines and patient tumors, with relevant diagnostic, clinical and therapeutic implications.

The HSP90 inhibitor ganetespib potentiates the antitumor activity of EGFR tyrosine kinase inhibition in mutant and wild-type non-small cell lung cancer

Small molecule inhibitors of epidermal growth factor receptor (EGFR) tyrosine kinase activity, such as erlotinib and gefitinib, revolutionized therapy for non-small cell lung cancer (NSCLC) patients whose tumors harbor activating EGFR mutations. However, mechanisms to overcome the invariable development of acquired resistance to such agents, as well as realizing their full clinical potential within the context of wild-type EGFR (WT-EGFR) disease, remain to be established. Here, the antitumor efficacy of targeted EGFR tyrosine kinase inhibitors (TKIs) and the HSP90 inhibitor ganetespib, alone and in combination, were evaluated in NSCLC. Ganetespib potentiated the efficacy of erlotinib in TKI-sensitive, mutant EGFR-driven NCI-HCC827 xenograft tumors, with combination treatment causing significant tumor regressions. In erlotinib-resistant NCI-H1975 xenografts, concurrent administration of ganetespib overcame erlotinib resistance to significantly improve tumor growth inhibition. Ganetespib co-treatment also significantly enhanced antitumor responses to afatinib in the same model. In WT-EGFR cell lines, ganetespib potently reduced cell viability. In NCI-H1666 cells, ganetespib-induced loss of client protein expression, perturbation of oncogenic signaling pathways, and induction of apoptosis translated to robust single-agent activity in vivo. Dual ganetespib/erlotinib therapy induced regressions in NCI-H322 xenograft tumors, indicating that the sensitizing properties of ganetespib for erlotinib were conserved within the WT-EGFR setting. Mechanistically, combined ganetespib/erlotinib exposure stabilized EGFR protein levels in an inactive state and completely abrogated extracellular-signal-regulated kinase (ERK) and AKT signaling activity. Thus, selective HSP90 blockade by ganetespib represents a potentially important complementary strategy to targeted TKI inhibition alone for inducing substantial antitumor responses and overcoming resistance, in both the mutant and WT-EGFR settings.

A randomized phase II study of erlotinib plus nab-paclitaxel versus erlotinib alone as second-line therapy for Chinese patients with advanced EGFR wild-type non-small-cell lung cancer

Erlotinib is a standard second-line therapy for patients with advanced non-small-cell lung cancer (NSCLC). However, its efficacy for those patients with epidermal growth factor receptor (EGFR) wild-type (WT) tumors is undecided. In this randomized phase II study, NSCLC patients with EGFR-WT tumors, who had been treated with platinum-based chemotherapy but still developed disease progression, were assigned to receive second-line treatment of erlotinib plus nab-paclitaxel or erlotinib alone. We found PFS and OS were significantly improved by erlotinib plus nab-paclitaxel. The adverse events were also well tolerable.

Icotinib antagonizes ABCG2-mediated multidrug resistance, but not the pemetrexed resistance mediated by thymidylate synthase and ABCG2

ABCG2 is a potential biomarker causing multidrug resistance (MDR) in Non-Small Cell Lung Cancer (NSCLC). We conducted this study to investigate whether Icotinib, a small-molecule inhibitor of EGFR tyrosine kinase, could interact with ABCG2 transporter in NSCLC. Our results showed that Icotinib reversed ABCG2-mediated MDR by antagonizing the drug efflux function of ABCG2. Icotinib stimulated the ATPase activity in a concentration-dependent manner and inhibited the photolabeling of ABCG2 with [125I]-Iodoarylazidoprazosin, demonstrating that it interacts at the drug-binding pocket. Homology modeling predicted the binding conformation of Icotinib at Asn629 centroid-based grid of ABCG2. However, Icotinib at reversal concentration did not affect the expression levels of AKT and ABCG2. Furthermore, a combination of Icotinib and topotecan exhibited significant synergistic anticancer activity against NCI-H460/MX20 tumor xenografts. However, the inhibition of transport activity of ABCG2 was insufficient to overcome pemetrexed resistance in NCI-H460/MX20 cells, which was due to the co-upregulated thymidylate synthase (TS) and ABCG2 expression. This is the first report to show that the up-regulation of TS in ABCG2-overexpressing cell line NCI-H460/MX20 may play a role of resistance to pemetrexate. Our findings suggested different possible strategies of overcoming the resistance of topotecan and pemetrexed in the NSCLC patients.

A phase II trial of gefitinib monotherapy in pretreated patients with advanced non-small cell lung cancer not harboring activating EGFR mutations: implications of sensitive EGFR mutation test

PURPOSE

Efficacy of gefitinib therapy strongly depends on epidermal growth factor receptor (EGFR) mutation status in patients with non-small cell lung cancer (NSCLC). However, cumulative data from many clinical studies demonstrated that some patients with wild-type (WT) EGFR also responded to gefitinib with durable disease control rate (DCR). The aim of this trial was to evaluate the efficacy and toxicity of gefitinib in NSCLC patients with WT EGFR who failed previous chemotherapy.

PATIENTS AND METHODS

Patients with advanced or recurrent NSCLC whose tumors have WT EGFR were eligible. Gefitinib (250 mg/day) was administered until disease progression or unacceptable toxicity occurred. The primary end point was DCR at 8 weeks.

RESULTS

A total of 85 patients (53 men and 32 women; median age, 60 years; range 30-86) were enrolled between October 2010 and May 2013. Seventy-four patients (87.1 %) had adenocarcinoma. Forty-two patients (49.4 %) were treated with gefitinib as second-line chemotherapy. Eleven patients showed partial response, and 21 had stable disease. Thus, objective response rate was 12.9 %, and DCR at 8 weeks was 37.6 %. The median progression-free survival (PFS) and overall survival were 1.9 and 10.9 months, respectively. Skin rash was the most common side effect. It is of note that patients with skin rash of any grade had improved PFS with gefitinib as compared with patients experiencing no skin rash (median PFS: 3.0 vs. 1.7 months, P = 0.004). One patient developed interstitial lung disease (grade 2). Of 11 gefitinib responders, 6 patients were identified as having tumor with activating EGFR mutation by peptide nucleic acid (PNA)-mediated PCR clamping method. Regarding the outcomes of the 79 patients, excluding 6 positive mutations, the response rate was 6.3 %, and DCR at 8 weeks was 31.8 %.

CONCLUSION

Small proportion of NSCLC patients with the WT EGFR benefits with gefitinib. Optimized diagnosis through more sensitive bioassay could have major consequences in terms of the selection of candidate for EGFR TKI in patients with WT EGFR by direct sequencing.

QSAR based model for discriminating EGFR inhibitors and non-inhibitors using Random forest

BACKGROUND

Epidermal Growth Factor Receptor (EGFR) is a well-characterized cancer drug target. In the past, several QSAR models have been developed for predicting inhibition activity of molecules against EGFR. These models are useful to a limited set of molecules for a particular class like quinazoline-derivatives. In this study, an attempt has been made to develop prediction models on a large set of molecules (~3500 molecules) that include diverse scaffolds like quinazoline, pyrimidine, quinoline and indole.

RESULTS

We train, test and validate our classification models on a dataset called EGFR10 that contains 508 inhibitors (having inhibition activity IC50 less than 10 nM) and 2997 non-inhibitors. Our Random forest based model achieved maximum MCC 0.49 with accuracy 83.7% on a validation set using 881 PubChem fingerprints. In this study, frequency-based feature selection technique has been used to identify best fingerprints. It was observed that PubChem fingerprints FP380 (C(~O) (~O)), FP579 (O = C-C-C-C), FP388 (C(:C) (:N) (:N)) and FP 816 (ClC1CC(Br)CCC1) are more frequent in the inhibitors in comparison to non-inhibitors. In addition, we created different datasets namely EGFR100 containing inhibitors having IC50 < 100 nM and EGFR1000 containing inhibitors having IC50 < 1000 nM. We trained, test and validate our models on datasets EGFR100 and EGFR1000 datasets and achieved and maximum MCC 0.58 and 0.71 respectively. In addition, models were developed for predicting quinazoline and pyrimidine based EGFR inhibitors.

CONCLUSIONS

In summary, models have been developed on a large set of molecules of various classes for discriminating EGFR inhibitors and non-inhibitors. These highly accurate prediction models can be used to design and discover novel EGFR inhibitors. In order to provide service to the scientific community, a web server/standalone EGFRpred also has been developed ( http://crdd.osdd.net/oscadd/egfrpred/ ).