Association of PD-L1 overexpression with activating EGFR mutations in surgically resected nonsmall-cell lung cancer

BACKGROUND

Recent clinical trials have shown that immune-checkpoint blockade yields a clinical response in a subset of individuals with advanced nonsmall-cell lung cancer (NSCLC). We examined whether the expression of programmed death-ligand 1 (PD-L1) is related to clinicopathologic or prognostic factors in patients with surgically resected NSCLC.

PATIENTS AND METHODS

The expression of PD-L1 was evaluated by immunohistochemical analysis in 164 specimens of surgically resected NSCLC. Cell surface expression of PD-L1 in NSCLC cell lines was quantified by flow cytometry.

RESULTS

Expression of PD-L1 in tumor specimens was significantly higher for women than for men, for never smokers than for smokers, and for patients with adenocarcinoma than for those with squamous cell carcinoma. Multivariate analysis revealed that the presence of epidermal growth factor receptor gene (EGFR) mutations and adenocarcinoma histology were significantly associated with increased PD-L1 expression in a manner independent of other factors. Cell surface expression of PD-L1 was also significantly higher in NSCLC cell lines positive for activating EGFR mutations than in those with wild-type EGFR. The EGFR inhibitor erlotinib downregulated PD-L1 expression in the former cell lines but not in the latter, suggesting that PD-L1 expression is increased by EGFR signaling conferred by activating EGFR mutations. A high level of PD-L1 expression in resected tumor tissue was associated with a significantly shorter overall survival for NSCLC patients.

CONCLUSIONS

High expression of PD-L1 was associated with the presence of EGFR mutations in surgically resected NSCLC and was an independent negative prognostic factor for this disease.

Mutant allele frequency predicts the efficacy of EGFR-TKIs in lung adenocarcinoma harboring the L858R mutation

BACKGROUND

Whether the mutant allele frequency (MAF) may also have predictive implications for tyrosine kinase inhibitor (TKI) therapy in patients with advanced epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma (AELAd) remains unknown.

PATIENTS AND METHODS

Based on a biobanking system in conjunction with our institution, we assessed EGFR mutation status using pyrosequencing (Py) and by outsourcing laboratory tests, such as the Cycleave (Cy) and the Scorpion ARMS (A).

RESULTS

Out of 705 patients enrolled in the Shizuoka Lung Cancer Mutation Study between July 2011 and March 2013, 102 AELAd patients were identified as carrying the L858R mutation (L858Rm) using Py to analyze histological specimens. Of these 102 patients, the EGFR mutation status was assessed using both Py and Cy in 48 patients: the median MAF of L858R (MAFLR) was 18.5% (range: 8%-82%), and 45 patients (94%) were identified as having an L858Rm using both Py and Cy. Three patients (6%) with discrepant L858Rm findings were only identified using Py. The plotting of a receiver operating characteristic curve to identify the discordance in L858Rm findings showed that the area under the curve for MAFLR was 0.967 (95% confidence interval: 0.91-1) and that an MAFLR of 9% resulted in high sensitivity (100%) and specificity (99%). Also, 29 patients with AELAd, excluding those with postoperative recurrences, had their L858R status assessed using Cy or A. The median age, 69 years (range: 47-84 years); male/female, 14 (48%)/15 (52%); smokers/never-smokers 13 (45%)/16 (55%); ECOG PS 0-1/2-3, 26 (90%)/3 (10%); stage IIIB/IV, 4 (14%)/25 (86%); median MAFLR, 18% (range: 8%-63%). Patients with an MAFLR of ≤9% had a significantly shorter progression-free survival (PFS) period after TKI therapy than those with an MAFLR of >9% (mPFS: 92 versus 284 days, P = 0.0027).

CONCLUSION

The MAF may be a potential predictive factor of TKI treatment efficacy in patients with AELAd carrying the L858Rm.

The new concepts on overcoming drug resistance in lung cancer

Lung cancer is one of the most deadly diseases worldwide. The current first-line therapies include chemotherapy using epidermal growth factor receptor tyrosine kinase inhibitors and radiotherapies. With the current progress in identifying new molecular targets, acquired drug resistance stands as an obstacle for good prognosis. About half the patients receiving epidermal growth factor receptor-tyrosine kinase inhibitor treatments develop resistance. Although extensive studies have been applied to elucidate the underlying mechanisms, evidence is far from enough to establish a well-defined picture to correct resistance. In the review, we will discuss four different currently developed strategies that have the potential to overcome drug resistance in lung cancer therapies and facilitate prolonged anticancer effects of the first-line therapies.

Predictive role of CEA and CYFRA 21-1 in patients with advanced-stage NSCLC treated with erlotinib

BACKGROUND

Tumor biomarkers are used for predicting therapy effect and prognosis of patients with non-small cell lung cancer (NSCLC). We focused on their potential role in prediction of the efficacy of erlotinib.

PATIENTS AND METHODS

In a total of 144 patients with advanced-stage (IIIB or IV) NSCLC treated with erlotinib, pre-treatment levels of soluble carcinoembryonic antigen (CEA) and cytokeratin markers in serum were measured.

RESULTS

The median progression-free and overall survival for patients with a high level of carcinoembryonic antigen (CEA) was 1.9 and 8.6 vs. 2.9 and 16.1 months for patients with low CEA (p=0.046 and p=0.116). The respective medians for patients with a high level of cytokeratin-19 fragment were 1.9 and 6.1 vs. 3.4 and 23.8 months for patients with the low cytokeratin-19 fragment (p<0.001 and p<0.001).

CONCLUSION

High pre-treatment serum levels of one or both biomarkers are associated with poor outcome of patients with NSCLC treated with erlotinib.

Gefitinib and afatinib treatment in an advanced non-small cell lung cancer (NSCLC) patient undergoing hemodialysis

Renal failure in cancer patients is not a rare clinical condition and often contraindicates anticancer drug treatment; moreover, chemotherapeutic drugs are frequently identified as possible iatrogenic cause of renal failure. Molecular therapies, when appropriate, could represent a therapeutic option for cancer patients with severe renal disease, but the lack of knowledge in this field, at present, limits their use in patients undergoing dialysis. Herein we describe a case, at our knowledge the first reported, of a patient with advanced lung adenocarcinoma on maintenance hemodialysis treated with gefitinib and then with afatinib; we also reviewed the literature on epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitors (TKIs) used in NSCLC patients with concomitant renal impairment.

Treating advanced non-small-cell lung cancer in Chinese patients: focus on icotinib

Icotinib hydrochloride is an orally administered small-molecule reversible tyrosine kinase inhibitor that has been independently researched and developed and has independent intellectual property rights in the People's Republic of China. Clinical trials have demonstrated that the response to icotinib among advanced non-small-cell lung cancer (NSCLC) patients who received at least one platinum-based chemotherapy regimen was not inferior to gefitinib. Since being launched August 2011 in the People's Republic of China, icotinib has been widely used in clinics, and has become an important treatment option for Chinese patients with advanced NSCLC. The present study presents the Phase I, II, and III clinical trials of icotinib and discusses current clinical applications in the People's Republic of China and future research directions.

Response to pemetrexed rechallenge after acquired resistance of EGFR-TKI in a patient with advanced NSCLC

Acquired resistance of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) has been developed as an important clinical problem though EGFR-TKI such as gefitinib, erlotinib and afatinib [1,2] has achieved 8-14 months of progression free survival in advanced non-small cell lung cancer (NSCLC) patient with EGFR mutation. We report a case here that an advanced lung adenocarcinoma with L858R mutation responded well to pemetrexed rechallenge after acquired resistance of erlotinib.

A multicenter phase II study of sorafenib monotherapy in clinically selected patients with advanced lung adenocarcinoma after failure of EGFR-TKI therapy (Chinese Thoracic Oncology Group, CTONG 0805)

OBJECTIVES

Aim of the study was to investigate efficacy and safety of sorafenib in patients with advanced lung adenocarcinoma after failure of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) therapy.

PATIENTS AND METHODS

Patients who were diagnosed with stage IIIB or stage IV lung adenocarcinoma, and benefited from one prior EGFR-TKI therapy and then failed, were eligible. No more than one previous chemotherapy regimen was permitted. Patients received oral sorafenib 400mg twice daily continuously until disease progression or intolerable toxicity. Primary endpoint was disease control rate (DCR). Secondary endpoints included safety, progression-free survival (PFS) and overall survival (OS). For patients who agreed to provide peripheral blood or tumor tissue, we analyzed the genotype of Bcl-2-interacting mediator of cell death (BIM) deletion polymorphism and EGFR mutation status.

RESULTS

Of 65 enrolled patients, 64 were evaluable. The DCR was 32.8%, which did not meet the predefined statistical hypothesis of 38.4%. The median PFS and OS were 3.7 months [95% (confidence interval), 3.5-3.9 months] and 7.4 months (95% CI, 5.7-9.2 months), respectively. Logistic regression analysis showed no correlation between DCR and age, gender, smoking status and performance status. Hand-foot syndrome (HFS) was the predominant toxicity occurring in 71.9% of patients. Fourteen patients (21.9%) had ≥ grade 2 dermatologic reactions that resulted sorafenib dose reduction in three patients (4.7%). Of 36 patients, the BIM deletion polymorphism was found in 3, and no response to sorafenib was observed. In 30 tumor tissues, 22 EGFR active mutations were found. The DCR had no significant difference between mutation-positive and wild-type patients (31.8% vs. 42.9%, respectively; HR, 0.622; p=0.665).

CONCLUSION

Sorafenib monotherapy did not achieve positive result in patients defined in our trial and we need better biomarker to determine the population who can benefit from sorafenib treatment (ClinicalTrials.gov number: NCT00922584).

The evaluation of efficacy and safety of sunitinib on EGFR-TKI pretreated advanced non-small cell lung cancer patients in China

BACKGROUND

Sunitinib is an oral multitargeted tyrosine kinase inhibitor (TKI) exhibiting antiagiogenic and antitumor effects.

OBJECTIVE

To evaluate the efficacy and potential toxicity of sunitinib therapy in advanced non-small cell lung cancer (NSCLC) patients in China.

METHODS

From January 2009 to August 2011, 30 patients with stage IV NSCLC, who were pretreated with the epidermal growth factor receptor (EGFR)-TKIs and then received sunitinib, were retrospectively reviewed. Univariate and multivariate Cox proportional hazard regression analysis was performed to determine the potential prognostic risk factors influencing NSCLC survival.

RESULTS

The median progression-free survival (PFS) and median overall survival (OS) of all 30 treated patients was 1.25 months [95% confidence interval (CI): 0.90-1.9 months] and 3.40 months (95% CI: 3.00-6.80 months), respectively. Cox regression analysis suggested that Eastern Cooperative Oncology Group (ECOG) performance status (PS) is predictive of both PFS (P=0.001) and OS (P<0.001). Common adverse events (AEs) included hand-foot syndrome (53.3%), mucositis (40.0%), rash (36.7%) and diarrhea (33.3%).

CONCLUSION

No sign of overall clinical benefits of sunitinib was detected in patients with pretreated EGFR-TKIs. Most patients suffered AEs from mild to moderate severity. ECOG PS is highly associated with PFS and OS rate. Further studies in NSCLC are required to determine whether sunitinib is beneficial nor not.

Reversion of erlotinib-acquired resistance twice by chemotherapy: a case report

Epidermal growth factor receptor (EGFR) mutations in patients with non-small cell lung cancer (NSCLC) usually develop disease progression after a median of 10 to 14 mo on tyrosine kinase inhibitor (TKI). Several mechanisms of resistance to TKI have been described, threonine-methionine substitution at position 790 (T790M), mesenchymal-epithelial transition factor (MET) amplification, overexpression of hepatocyte growth factor (HGF), upregulation of insulin-like growth factor (IGF) receptor signaling, transformation to small cell lung cancer, and so on. A variety of different therapeutic approaches aimed at overcoming resistance are motivated, irreversible EGFR inhibitors, combination with EGFR targeted antibodies, mesenchymal-epithelial transition factor (MET) inhibitors, HGF inhibitors, and so forth. Nevertheless, the results were not optimistic. Here we report a case of reversion of erlotinib-acquired resistance twice, and had a good improvement of outcomes every time. There are some possible reasons for this phenomenon. Considering this report, the patients who acquired resistance after retreatment of EGFR-TKI, using EGFR-TKI repeatedly may be a choice selectively.

MiR-21 overexpression is associated with acquired resistance of EGFR-TKI in non-small cell lung cancer

BACKGROUND AND PURPOSE

With the increasing use of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) in patients with advanced non-small cell lung cancer (NSCLC), its acquired resistance has become a major clinical problem. Recent studies revealed that miR-21 was involved into the resistance of cytotoxic agents. The aim of this study was to investigate its role in the acquired resistance of NSCLC to EGFR-TKI.

METHODS

EGFR-TKI-sensitive human lung adenocarcinoma cell line PC9 and the acquired resistant cell line, PC9R, were used. Lentiviral vectors were used to infect PC9 or PC9R to regulate the miR-21 expression. The expression of targeted proteins PTEN and PDCD4 was controlled by RNA interference. MicroRNA array, RT-PCR and TaqMan MicroRNA Assays were used to detect miR-21 expression. The MTT and Annexin V assays were used to determine proliferation and apoptosis. Western Blot and immunohistochemistry were used to analyze target protein expression (PTEN, PDCD4, Akt, p-Akt). We also constructed PC9R xenograft tumor model to observe the relationship between miR-21 and EGFR-TKI resistance in vivo and validated it in the clinical serum specimens of NSCLC patients treated with EGFR-TKI.

RESULT

MiR-21 was overexpressed in the EGFR-TKI resistant cell line PC9R relative to PC9. The level of miR-21 was reversely correlated with the expression of PTEN and PDCD4 and positive correlated with PI3K/Akt pathway. Inhibiting miR-21 with lentivirus vector induces apoptosis in PC9R cell line and inhibiting miR-21with ASO suppressed tumor growth in nude mice treated with EGFR-TKI. Furthermore, serum miR-21 expression in NSCLC patients treated with EGFR-TKI was significantly higher at the time of acquiring resistance than at baseline (p<0.01).

CONCLUSION

miR-21 is involved in acquired resistance of EGFR-TKI in NSCLC, which is mediated by down-regulating PTEN and PDCD4 and activating PI3K/Akt pathway.

Therapeutic efficacy of gefitinib and erlotinib in patients with advanced lung adenosquamous carcinoma

BACKGROUND

Adenosquamous carcinoma (ASC) of the lung is a rare subtype of nonsmall-cell lung cancer (NSCLC). To date, the efficacious targeted therapy for advanced ASC remains unclear and the epidermal growth factor receptor (EGFR) mutation rate is not well known.

METHODS

We retrospectively reviewed clinical information of patients with ASC who were treated with gefitinib or erlotinib at Zhejiang Cancer Hospital between January 2007 and December 2011. Survival analysis was evaluated by the Kaplan-Meier method. EGFR mutations were assessed in part using direct sequencing methods.

RESULTS

In total, 49 patients with a median age of 57 years were used in this study. Thirteen patients achieved a partial response and 19 had disease stabilization. The objective response rate was 26.5%, and the disease control rate was 65.3%. The median progression-free survival and overall survival were 4.3 and 17.6 months, respectively. In 21 patients with adequate specimens for molecular analysis, 7 (33.3%) had EGFR mutations (4 with deletions within exon 19 and 3 with L858R messenger mutation in exon 21). EGFR mutations were significantly more frequent in women (4/9, 44.4%) than men (3/12, 25%), never-smokers (6/15, 40%), and smokers (1/6, 16.7%).

CONCLUSION

EGFR-tyrosine kinase inhibitor (TKI) is an effective treatment for ASC. The frequency of EGFR mutation and clinical characteristics of the EGFR mutants in ASC are similar to those of Asian patients with adenocarcinoma.

Notch-1 contributes to epidermal growth factor receptor tyrosine kinase inhibitor acquired resistance in non-small cell lung cancer in vitro and in vivo

Acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) occurs in non-small cell lung cancer (NSCLC) patients who initially respond to TKI treatment but whose cancer then progresses. Recent studies have shown that Notch signal is associated with drug resistance. However, the exact mechanism of Notch during acquisition of resistance to EGFR-TKI in human lung cancer remains unclear. In the present study, we showed that the expression of Notch-1 was highly upregulated in EGFR-TKI acquired resistant lung cancer cells. More importantly, Notch-1 contributed to the acquisition of the epithelial-mesenchymal transition (EMT) phenotype, which was critically associated with acquired resistance to EGFR-TKI. Silencing of Notch-1 using siRNA resulted in mesenchymal-epithelial transition (MET), which was associated with impaired invasion and anchorage-independent growth of lung cancer and resensitisation to gefitinib in acquired resistant NSCLC cells. Finally, gefitinib treatment of Balb/c nu/nu with acquired resistant lung cancer xenografts in combination with Notch inhibitor N-[N-(3,5-difluorophenacetyl)-L-alanyl]-(S)-phenylglycine t-butyl ester (DAPT) resulted in effective tumour growth retardation, with decreased proliferative activity and increased apoptotic activity. Collectively, these data suggest that Notch-1 might play a novel role in acquired resistance to gefitinib, which could be reversed by inhibiting Notch-1.

Efficacy of erlotinib plus concurrent whole-brain radiation therapy for patients with brain metastases from non-small cell lung cancer

Treatment and control of brain metastases are important in patients with non-small cell lung cancer (NSCLC). Whole brain radiation therapy (WBRT) has a major role in the management of brain metastasis. Recently, efficacy erlotinib plus concurrent WBRT for patients with brain metastases from NSCLC was reported. Herein, we discussed the results and commented the clinical matters in future.

Identification of α1-antitrypsin as a potential prognostic biomarker for advanced nonsmall cell lung cancer treated with epidermal growth factor receptor tyrosine kinase inhibitors by proteomic analysis

OBJECTIVE

This retrospective study attempted to identify serum biomarkers that could help to indicate treatment response in advanced nonsmall-cell lung cancer (NSCLC) patients receiving epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) treatment.

METHODS

Two-dimensional fluorescence difference gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were used to identify proteins expressed in serum samples from NSCLC patients with long (>6-month) progression-free survival (PFS) periods, following EGFR-TKI treatment.

RESULTS

Serum amyloid P component (APCS), α1-antitrypsin (AAT), fibrinogen-α (FGA), keratin type I cytoskeletal 10 (KRT10) and serotransferrin (TF) expression differed between samples taken from 18 patients before treatment (baseline) and when progressive disease (PD) was observed, during treatment. Changes in AAT, KRT10 and APCS levels were validated by Western blot analysis in the sample pool; findings were further validated by Western blot analysis in a random sample of four patients. These proteins were also present in serum samples obtained from the same patients at the partial response (PR) timepoint during EGFR-TKI treatment. AAT was upregulated at PD compared with baseline, but downregulated during the PR phase.

CONCLUSION

These observations suggest that AAT could be used as a serological biomarker for predicting the utility of EGFR-TKI treatment for advanced NSCLC.

Tumor response and health-related quality of life in clinically selected patients from Asia with advanced non-small-cell lung cancer treated with first-line gefitinib: post hoc analyses from the IPASS study

BACKGROUND

In IPASS (NCT00322452), progression-free survival (PFS, primary endpoint) was significantly longer with first-line gefitinib versus carboplatin/paclitaxel in never/light ex-smokers with advanced pulmonary adenocarcinoma in Asia, both in the overall intent-to-treat (ITT) population and in the EGFR mutation-positive subgroup. To further characterize the clinical relevance of these data, we investigated objective response rate (ORR) and health-related quality of life (HRQoL) in patients treated with gefitinib.

METHODS

Objective response was assessed (RECIST) 6-weekly (previously reported). Post hoc assessments included median time to response, median duration of response and change in tumor size. The analysis of response population included those patients treated with gefitinib who responded (n = 262 from ITT; n = 94 from EGFR mutation-positive subgroup). The percentage of patients with deterioration in HRQoL (Functional Assessment of Cancer Therapy-Lung [FACT-L], Trial Outcome Index [TOI]) and symptoms (Lung Cancer Subscale [LCS]) at 4 months post-randomization was analyzed according to progression status (EFQ population grouped by progressors/non-progressors in both treatment arms). The ORR (ITT) and incidence of skin rash/acne (evaluable-for-safety) were summarized.

RESULTS

In patients whose tumors responded to gefitinib, median time to response was 6.1 weeks in the ITT population (n = 262) and 6.0 weeks in the EGFR mutation-positive subgroup (n = 94); median duration of response was 9.7 and 8.7 months in these groups, respectively. There was significant tumor shrinkage with gefitinib. A greater percentage of patients in the EFQ population whose tumors progressed experienced deterioration in HRQoL and symptoms at 4 months versus patients whose tumors did not progress (FACT-L 33.7% vs 16.3%; TOI 33.7% vs 13.2%; LCS 31.7% vs 15.5%). In the gefitinib arm of the EFS population, incidence of rash was 75.8% and 68.1% in EGFR mutation-positive and -negative subgroups, respectively (with ORR for the gefitinib arm of the ITT 71.2% vs 1.1%, respectively).

CONCLUSIONS

Patients whose tumors responded to first-line gefitinib experienced significant tumor shrinkage and a rapid, durable response. Deterioration in HRQoL and lung cancer symptoms at 4 months post-randomization was found to be associated with tumor progression, highlighting the role of patient-reported outcomes in the evaluation of advanced NSCLC disease. Rash was not supported as a predictive marker of response to gefitinib.