EGFR突变晚期非小细胞肺癌免疫治疗的研究进展

肺癌是全球癌症相关死亡的主要原因。表皮生长因子受体是亚洲肺腺癌患者最常见的突变类型。酪氨酸激酶抑制剂是表皮生长因子受体突变非小细胞肺癌一线首选治疗，但获得性耐药限制了其长期疗效，对于耐药后治疗仍没有有效选择方案。目前，免疫治疗延长了部分患者的生存时间,但在表皮生长因子受体突变非小细胞肺癌中反应较差，介导其疗效不佳的原因仍尚不明确。多种生物标志物的联合评价更能准确预测其免疫治疗疗效并筛选潜在获益人群。联合抗血管生成及新型靶点药物治疗具有免疫增敏作用。本文就表皮生长因子受体突变晚期非小细胞肺癌免疫治疗研究现状、免疫治疗潜在获益人群及免疫联合治疗新策略进行综述。     

Schedule-dependent antitumor activity of the combination with erlotinib and docetaxel in human non-small cell lung cancer cells with EGFR mutation, KRAS mutation or both wild-type EGFR and KRAS

Erlotinib is used as a standard treatment for recurrent advanced non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) mutations in NSCLC have been shown to be a predictive factor of erlotinib, although the relationship between K-ras oncogene (KRAS) mutations and erlotinib resistance is controversial. Recently, in vitro sequence-dependent interactions of erlotinib and docetaxel have been studied on as a novel therapeutic approach against NSCLC. The purpose of the present study was to determine the optimum novel regimen of erlotinib and docetaxel against NSCLC cells which have EGFR mutation (HCC827 cells), KRAS mutation (A549 cells) or both wild-type (NCI-H292 cells). First, we analyzed the effects of in vitro combination for cell proliferation-inhibition using a combination index. In all cell lines, docetaxel followed by erlotinib treatment showed nearly additive effects. On the other hand, erlotinib followed by docetaxel treatment showed remarkable antagonistic interactions. Second, we examined the effect of combinations on the in vitro apoptosis induction. Erlotinib followed by docetaxel treatment reduced apoptosis induction compared with docetaxel alone; in contrast, docetaxel followed by erlotinib treatment had no inhibitory effects on docetaxel-induced apoptosis in any of the cell lines. Finally, an in vivo tumor growth inhibition test was performed using xenograft models. Docetaxel followed by erlotinib administration resulted in significant tumor growth inhibition compared with erlotinib or docetaxel monotherapy in all models. In conclusion, we demonstrated that docetaxel followed by erlotinib therapy was a potentially optimum regimen against NSCLC regardless of the mutation status of EGFR and KRAS.     

Potential crosstalk between cofilin-1 and EGFR pathways in cisplatin resistance of non-small-cell lung cancer

Current challenge in oncology is to establish the concept of personalized medicine in clinical practice. In this context, non-small-cell lung cancer (NSCLC) presents clinical, histological and molecular heterogeneity, being one of the most genomically diverse of all cancers. Recent advances added Epidermal Growth Factor Receptor (EGFR) as a predictive biomarker for patients with advanced NSCLC. In tumors with activating EGFR mutations, tyrosine kinase inhibitors (TKI) are indicated as first-line treatment, although restricted to a very small target population. In this context, cofilin-1 (a cytosolic protein involved with actin dynamics) has been widely studied as a biomarker of an aggressive phenotype in tumors, and overexpression of cofilin-1 is associated with cisplatin resistance and poor prognosis in NSCLC. Here, we gather information about the predictive potential of cofilin-1 and reviewed the crosstalk between cofilin-1/EGFR pathways. We aimed to highlight new perspectives of how these interactions might affect cisplatin resistance in NSCLC. We propose that cofilin-1 quantification in clinical samples in combination with presence/absence of EGFR mutation could be used to select patients that would benefit from TKI''s treatment. This information is of paramount importance and could result in a possibility of guiding more effective treatments to NSCLC patients.     

miRNAs与非小细胞肺癌EGFR突变及放疗相关性研究进展

EGFR作为NSCLC靶向治疗的热点,近年来其在分子生物学水平的研究众多。而放疗作为一种NSCLC重要的传统治疗方法,其疗效与EGFR突变及过表达相关。放疗联合EGFR-TKI在NSCLC治疗上的疗效还缺乏Ⅲ期临床结果。miRNAs能够调控肿瘤相关基因表达,影响肿瘤生物学活动。近来研究显示miRNAs对EGFR突变、EGFR-TKI和放疗均存在正向或负向的调控作用,其具体机制已部分阐明。现就miRNAs对EGFR突变、EGFR-TKI及放疗间相关性作一综述,旨在为miRNAs应用于放疗联合EGFR-TKI治疗NSCLC提供最新诊疗依据。     

Combined EGFR/MET or EGFR/HSP90 inhibition is effective in the treatment of lung cancers codriven by mutant EGFR containing T790M and MET

Tyrosine kinase inhibitors (TKI) that target the EGF receptor (EGFR) are effective in most non-small cell lung carcinoma (NSCLC) patients whose tumors harbor activating EGFR kinase domain mutations. Unfortunately, acquired resistance eventually emerges in these chronically treated cancers. Two of the most common mechanisms of acquired resistance to TKIs seen clinically are the acquisition of a secondary "gatekeeper" T790M EGFR mutation that increases the affinity of mutant EGFR for ATP and activation of MET to offset the loss of EGFR signaling. Although up to one-third of patient tumors resistant to reversible EGFR TKIs harbor concurrent T790M mutation and MET amplification, potential therapies for these tumors have not been modeled in vivo. In this study, we developed a preclinical platform to evaluate potential therapies by generating transgenic mouse lung cancer models expressing EGFR-mutant Del19-T790M or L858R-T790M, each with concurrent MET overexpression. We found that monotherapy targeting EGFR or MET alone did not produce significant tumor regression. In contrast, combination therapies targeting EGFR and MET simultaneously were highly efficacious against EGFR TKI-resistant tumors codriven by Del19-T790M or L858R-T790M and MET. Our findings therefore provide an in vivo model of intrinsic resistance to reversible TKIs and offer preclinical proof-of-principle that combination targeting of EGFR and MET may benefit patients with NSCLC.     

Alternating Therapy With Osimertinib and Afatinib Blockades EGFR Secondary Mutation in EGFR-Mutant Lung Cancer: A Single-Arm Phase II Trial

BackgroundResistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has limited treatment options for patients with EGFR-mutated non–small-cell lung cancer (NSCLC). Although osimertinib or afatinib alone induced drug-resistant clones with EGFR secondary mutation in a preclinical model, its combination prevented the appearance of these mutations. We investigated alternating-dose therapy of osimertinib and afatinib in patients with EGFR-mutant NSCLC in a single-arm Phase II trial.MethodsTreatment-naïve patients with stage IV NSCLC harboring an activating EGFR mutation were enrolled. Alternating cycles of osimertinib (80 mg/day) followed by afatinib (20 mg/day) were administered every 8 weeks. Genomic analysis was performed using circulating tumor DNA obtained before and after the treatment.ResultsAmong the 46 enrolled patients, the median progression-free survival was 20.2 months. The overall response rate was 69.6%. The median overall survival was not reached. Among the 26 plasma samples obtained after the acquisition of resistance, 3 showed an increased MET gene copy number, and 1 showed BRAF mutation. Meanwhile, no EGFR secondary mutation was detected.ConclusionThe efficacy of our treatment was not significantly different from osimertinib alone, as reported previously in untreated advanced NSCLC patients with EGFR mutations. Although the sample size was limited, this treatment may prevent the emergence of EGFR secondary mutations that trigger drug resistance. Further studies are warranted to establish the significance of this treatment.Clinical Trial RegistrationjRCTs051180009.     

A novel ALK secondary mutation and EGFR signaling cause resistance to ALK kinase inhibitors

Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKI), including crizotinib, are effective treatments in preclinical models and in cancer patients with ALK-translocated cancers. However, their efficacy will ultimately be limited by the development of acquired drug resistance. Here we report two mechanisms of ALK TKI resistance identified from a crizotinib-treated non-small cell lung cancer (NSCLC) patient and in a cell line generated from the resistant tumor (DFCI076) as well as from studying a resistant version of the ALK TKI (TAE684)-sensitive H3122 cell line. The crizotinib-resistant DFCI076 cell line harbored a unique L1152R ALK secondary mutation and was also resistant to the structurally unrelated ALK TKI TAE684. Although the DFCI076 cell line was still partially dependent on ALK for survival, it also contained concurrent coactivation of epidermal growth factor receptor (EGFR) signaling. In contrast, the TAE684-resistant (TR3) H3122 cell line did not contain an ALK secondary mutation but instead harbored coactivation of EGFR signaling. Dual inhibition of both ALK and EGFR was the most effective therapeutic strategy for the DFCI076 and H3122 TR3 cell lines. We further identified a subset (3/50; 6%) of treatment naive NSCLC patients with ALK rearrangements that also had concurrent EGFR activating mutations. Our studies identify resistance mechanisms to ALK TKIs mediated by both ALK and by a bypass signaling pathway mediated by EGFR. These mechanisms can occur independently, or in the same cancer, suggesting that the combination of both ALK and EGFR inhibitors may represent an effective therapy for these subsets of NSCLC patients.     

Novel therapeutic strategies for patients with NSCLC that do not respond to treatment with EGFR inhibitors

Introduction

Treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) yields tumour responses in non-small cell lung cancer (NSCLC) patients harbouring activating EGFR mutations. However, even in long-lasting responses, resistance to EGFR TKIs invariably occurs.

Areas covered

This review examines resistance mechanisms to EGFR TKI treatment, which mainly arise from secondary EGFR mutations. Other resistance-inducing processes include mesenchymal–epithelial transition factor (MET) amplification, epithelial–mesenchymal transformation, phenotypic change from NSCLC to small-cell lung carcinoma, and modifications in parallel signalling pathways. Current therapeutic strategies to overcome these EGFR TKI resistance mechanisms focus on the inhibition or blocking of multiple members of the ErbB family. Several molecules which target multiple ErbB receptors are being investigated in NSCLC and other indications including afatinib, an ErbB Family Blocker, as well as dacomitinib and lapatinib. Novel, non-quinazoline, EGFR inhibitors, that also target EGFR activating and resistance (T790M) mutations, are currently under clinical development. Other therapeutic strategies include inhibition of parallel and downstream pathways, using agents which target heat shock protein (HSP)90 or poly (ADP-ribose) polymerase in addition to mammalian target of rapamycin (mTOR), monoclonal antibodies against the insulin-like growth factor-1 receptor, and fulvestrant-mediated oestrogen receptor regulation.

Conclusion

Improved understanding of mechanisms underlying resistance to EGFR TKIs emphasises the importance of a genotype-guided approach to therapy. Elucidation of resistance mechanisms is indeed crucial to target innovative therapeutic approaches and to improve the efficacy of anticancer regimes in NSCLC.     

EGFR inhibitors in lung cancer

Targeted therapies inhibiting the epidermal growth factor receptor (EGFR) have been introduced in the treatment of patients with advanced non-small-cell lung cancer (NSCLC). Many inhibitors of the EGFR have been developed, targeting either the extracellular receptor domain with antibodies or the intracellular tyrosine kinase binding domain with small molecules. The tyrosine kinase inhibitor (TKI) gefitinib (Iressa) was the first targeted drug to be registered for the treatment of NSCLC after failure of chemotherapy. Given concurrently together with platinum combination chemotherapy both TKIs gefitinib and erlotinib (Tarceva) failed to increase activity. Sequential targeted therapy after chemotherapy is currently being investigated further. Studies with the monoclonal antibody cetuximab (Erbitux) combined with chemotherapy are ongoing. Side effects of the small molecules are mainly skin rash and diarrhea, whereas the antibodies do not give diarrhea. Selection of patients, based on molecular markers and patient characteristics, has become an important issue for the further development of these drugs, given there is activity in a relatively small group of patients with NSCLC. Newer drugs inhibiting more than one receptor pathway are being investigated in order to find activity in a broader group of patients.     

酪氨酸激酶抑制剂在非小细胞肺癌中的耐药机制

EGFR-TKIs在EGFR突变型非小细胞肺癌治疗中是非常有效的。然而在非小细胞肺癌EGFR突变患者中约有20%天然耐药,即使治疗有效,在10~16月左右会产生继发耐药。迄今为止,研究发现可能的继发性耐药机制包括EGFR二次突变、旁路激活、下游信号激活、小细胞转化及上皮-间质转化（EMT）等。近期,有研究发现BIM基因与TKI耐药相关。本文就有关耐药机制的近期研究进展作一综述。     

Emergence of RET rearrangement co-existing with activated EGFR mutation in EGFR-mutated NSCLC patients who had progressed on first- or second-generation EGFR TKI

ObjectivesThe gatekeeper mutation T790M mutation is the responsible for the majority of the resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in patients with EGFR-mutated non-small cell lung cancer (NSCLC). Other previously described resistance mechanisms include HER2 amplification, MET amplification, PIK3CA mutation, epithelial–mesenchymal transition (EMT), small cell transformation have also been identified. However other resistance mechanisms remains to be discovered.Materials and methodsHybrid-capture based comprehensive genomic profiling (CGP) was performed on pre- and post-EGFR TKI progression EGFR-mutated NSCLC tumor samples during routine clinical care. We identify two paired pre- and post-EGFR TKI progression EGFR-mutated NSCLC patient tumor samples where both post EGFR TKI samples harbored in-frame CCDC6-RET rearrangements but not in the pre-EGFR TKI tumor samples. Furthermore analysis of the clinical database revealed one additional NCOA4-RET rearrangement co-existing with activated EGFR mutation in an EGFR-mutated NSCLC patient who had progressed on afatinib. None of the known resistance mechanisms to EGFR TKI including EGFR T790M, EGFR amplification, HER2 amplification, MET amplification, PIK3CA mutation, BRAF mutation, EMT or small cell transformation was identified in the three post progression samples that now harbored RET rearrangements.Results and conclusionsThis is the first report of RET rearrangement co-existing with activated EGFR mutations in EGFR-mutated patients who had progressed on either first- or second generation EGFR TKI. As such, RET rearrangement may serve as a potential resistance mechanism to EGFR TKI in EGFR-mutated NSCLC.     

Continuation of epidermal growth factor receptor tyrosine kinase inhibitor treatment prolongs disease control in non-small-cell lung cancers with acquired resistance to EGFR tyrosine kinase inhibitors

Objectives

Patients with non-small-cell lung cancer (NSCLC) develop acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) after tumor regression. No approved targeted therapies are currently available after initial EGFR TKI treatment. This study investigated the efficacy of continuing EGFR TKI therapy with local treatments for patients with NSCLC and local progression or minimal/slow progression on TKI therapy.

Materials and Methods

Fifty-five patients with NSCLC treated with EGFR TKIs and developed acquired resistance to the drug were included. Initial response to target therapy, median progression free survival (PFS1), progression pattern, and first progression site were assessed. Median progression free survival to physician assessment progression (PFS2) and difference between PFS1 and PFS2 (PFS difference) were also recorded.

Results and Conclusion

PFS1 was 11.2 months, PFS2 was 20.3 months, and PFS difference was 8.3 months. Nineteen patients (34.5%) who manifested progression received local therapy, and 16 (28.6%) underwent rebiopsy after progression with six positive EGFR T790M mutations detected. Cox proportional hazards regression model showed that only the first line of treatment was significantly correlated with PFS difference. NSCLC patients with acquired resistance to EGFR TKIs could benefit from the same TKI therapy through months to years of disease control.     

Metformin and salinomycin as the best combination for the eradication of NSCLC monolayer cells and their alveospheres (cancer stem cells) irrespective of EGFR,KRAS, EML4/ALK and LKB1 status

The presence of cancer stem cells (CSCs) is linked to preexisting or acquired drug resistance and tumor relapse. Therefore, targeting both differentiated tumor cells and CSCs was suggested as an effective approach for non-small cell lung cancer (NSCLC) treatment. After screening of chemotherapeutic agents, tyrosine kinase inhibitors (TKIs) or monoclonal antibody in combination with the putative stem cell killer Salinomycin (SAL), we found Metformin (METF), which modestly exerted a growth inhibitory effect on monolayer cells and alveospheres/CSCs of 5 NSCLC cell lines regardless of their EGFR, KRAS, EML4/ALK and LKB1 status, interacted synergistically with SAL to effectively promote cell death. Inhibition of EGFR (AKT, ERK1/2) and mTOR (p70 s6k) signaling with the combination of METF and SAL can be augmented beyond that achieved using each agent individually. Phospho-kinase assay further suggested the multiple roles of this combination in reducing oncogenic effects of modules, such as ß-catenin, Src family kinases (Src, Lyn, Yes), Chk-2 and FAK. Remarkably, significant reduction of sphere formation was seen under combinatorial treatment in all investigated NSCLC cell lines. In conclusion, METF in combination with SAL could be a promising treatment option for patients with advanced NSCLC irrespective of their EGFR, KRAS, EML4/ALK and LKB1 status.     

Activity of EGFR TKIs in Caucasian Patients With NSCLC Harboring Potentially Sensitive Uncommon EGFR Mutations

BackgroundMolecular characterization of non–small-cell lung cancer (NSCLC), defined predictive and druggable mutations that greatly modified patient prognoses. The most frequent driver mutations detected in NSCLC are epidermal growth factor receptor (EGFR) mutations, accounting for approximately 90% of exon 19 deletions and exon 21 point mutations. The other EGFR mutations are classified as uncommon or nonclassical and include exon 18 point mutations, exon 20 insertions, and combined mutations, which present different sensitivity to tyrosine kinase inhibitor (TKI) targeting.Patients and MethodsWe collected data from EGFR TKI-naive patients with metastatic NSCLC, harboring EGFR exon 18 mutations and EGFR combined mutations treated with first- or second-generation EGFR TKIs. Efficacy end points were evaluated considering the activity of EGFR TKIs in exon 18 versus double-mutation EGFR groups.ResultsEighty-eight patients harboring uncommon EGFR mutations were evaluated in our analysis, and subdivided into 2 group: complex mutations (cohort A = 46 patients) and double mutations in exon 18 (cohort B = 42 patients). The results showed a median progression-free survival of 8.3 versus 12.3 months (hazard ratio [HR], 0.65; P = .06) and a median overall survival of 17.0 versus 31.0 months (HR, 0.62, P = .04) favoring the EGFR combination group. Within the combination group, no detrimental effect was associated with exon 20 mutations.ConclusionOur study confirmed that EGFR exon 18 and combination mutations might be considered potentially sensitive uncommon mutations, with a similar survival compared with the well known common EGFR mutations. Comparative analysis showed that patients with complex mutations achieved longer survival compared with the exon 18 group, without correlation with the presence of exon 20 mutations.     

免疫检查点抑制剂在EGFR突变非小细胞肺癌治疗应用的研究进展

目前,表皮生长因子受体酪氨酸激酶抑制剂(epidermal growth factor receptor-tyrosine kinase inhibitor,EGFR-TKI)是表皮生长因子受体(epidermal growth factor receptor,EGFR)基因敏感突变晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)的一线治疗标准,但大多数患者最终出现获得性耐药。而针对免疫检查点程序性死亡受体(programmed death-1,PD-1)及其配体(PD-1 ligand,PD-L1)的抑制剂取得突破性进展,改变了NSCLC的治疗模式。多项研究显示,EGFR敏感突变NSCLC患者免疫检查点抑制剂疗效不佳,其可能机制主要包括EGFR敏感突变患者PD-L1的低表达、抑制性免疫微环境、低肿瘤突变负荷等等。通过对EGFR突变NSCLC患者特殊人群的选择,免疫检查点抑制剂与其他药物的联合应用,可能为EGFR敏感突变NSCLC患者的治疗带来希望。本文将对此进行综述,以期为表皮生长因子受体突变的非小细胞肺癌患者的治疗带来新的希望。     

Coregulation of pathways in lung cancer patients with EGFR mutation: therapeutic opportunities

Epidermal growth factor receptor (EGFR) mutations in lung adenocarcinoma are a frequent class of driver mutations. Single EGFR tyrosine kinase inhibitor (TKI) provides substantial clinical benefit, but almost nil radiographic complete responses. Patients invariably progress, although survival can reach several years with post-treatment therapies, including EGFR TKIs, chemotherapy or other procedures. Endeavours have been clinically oriented to manage the acquisition of EGFR TKI-resistant mutations; however, basic principles on cancer evolution have not been considered in clinical trials. For years, evidence has displayed rapidly adaptive mechanisms of resistance to selective monotherapy, posing several dilemmas for the practitioner. Strict adherence to non-small cell lung cancer (NSCLC) guidelines is not always practical for addressing the clinical progression that EGFR-mutant lung adenocarcinoma patients suffer. The purpose of this review is to highlight regulatory mechanisms and signalling pathways that cause therapy-induced resistance to EGFR TKIs. It suggests combinatorial therapies that target EGFR, as well as potential mechanisms underlying EGFR-mutant NSCLC, alerting the reader to clinical opportunities that may lead to a deeper and more durable response. Molecular reprogramming contributes to EGFR TKI resistance, and the compiled information is relevant in understanding the development of new combined targeted strategies in EGFR-mutant NSCLC.Subject terms: Drug development, Predictive markers, Cancer therapeutic resistance     

Liquid Biopsy Testing for the Management of Patient with Non-Small Cell Lung Cancer Carrying a Rare Exon-20 EGFR Insertion

Increasing evidence suggests that liquid biopsy might play a relevant role in the management of metastatic non-small cell lung cancer (NSCLC) patients. Here, we show how the Molecular Tumor Board (MTB) in our cancer center employed liquid biopsy to support therapeutic decisions in a patient with NSCLC carrying a rare EGFR mutation. A 44-year-old woman, never-smoker with an EGFR, ALK, and ROS1-negative lung adenocarcinoma and multiple brain metastases received systemic therapy and surgery before being referred to our Institute. The MTB suggested NGS testing of tumor biopsy that revealed a rare exon-20 EGFR insertion (p.His773dup; c.2315_2316insCCA) and EGFR amplification. The MTB recommended treatment with erlotinib and follow-up with liquid biopsy, by using both cell-free DNA (cfDNA) and circulating tumor cells (CTCs). An increase of EGFR mutation levels in cfDNA revealed resistance to treatment about 6 months before clinical progression. Extremely low levels of EGFR p.T790M were detected at progression. Based on preclinical data suggesting activity of osimertinib against EGFR exon-20 insertions, the MTB recommended treatment with brain and bone radiotherapy and osimertinib. A dramatic reduction of EGFR mutation levels in the cfDNA was observed after 4 weeks of treatment. The PET scan demonstrated a metabolic partial remission that was maintained for 9 months. This case supports the evidence that liquid biopsy can aid in the management of metastatic NSCLC. It also suggests that treatment with osimertinib might be a therapeutic option in patients with EGFR exon-20 insertions when a clinical trial is not available.     

HDAC6-mediated EGFR stabilization and activation restrict cell response to sorafenib in non-small cell lung cancer cells

Sorafenib is a multi-targeted kinase inhibitor and has been the subject of extensive clinical research in advanced non-small cell lung cancer (NSCLC). However, sorafenib fails to improve overall survival of patients with advanced NSCLC. The molecular mechanisms that account for this phenomenon are unclear. Here we show that sorafenib treatment stabilizes epidermal growth factor receptor (EGFR) and activates EGFR pathway. Moreover, this is partly mediated by stabilization of histone deacetylase 6 (HDAC6), which has been shown to regulate EGFR endocytic trafficking and degradation. Overexpression of HDAC6 confers resistance to sorafenib in NSCLC cells. Inhibition of HDAC6 with selective inhibitors synergizes with sorafenib to kill NSCLC cells via inhibition of sorafenib-mediated EGFR pathway activation. Taken together, our findings might partly explain the failure of Phase III trial of sorafenib in improving overall survival of advanced NSCLC patients and bear possible implications for the improvement on the efficacy of sorafenib in treatment of NSCLC.     

厄洛替尼治疗EGFR野生型晚期非小细胞肺癌的疗效分析

目的:评价厄洛替尼治疗EGFR野生型NSCLC的疗效及安全性.方法:31名Ⅲ/Ⅳ期或术后复发,不携带EGFR敏感突变(外显子18、19、21)的NSCLC患者服用厄洛替尼(150 mg/d).结果:术后再发的,EGFR野生型的,Ⅲ期或Ⅳ期患者服用厄洛替尼(150 mg/d),1例完全缓解,4例部分缓解,8例疾病稳定.缓解率为17.2%,疾病控制率为44.8%.皮疹是最常见的不良反应(80.6%).有两名患者出现了间质性肺病.但所有这些不良反应均为可逆的,没有出现治疗相关死亡.中位无进展生存时间及中位生存时间分别为2.1个月与7.7个月.结论:厄洛替尼可能会成为化疗耐受的EGFR野生型NSCLC患者的一个替代方案.     

Combination therapy with anti-ErbB3 monoclonal antibodies and EGFR TKIs potently inhibits Non-small Cell Lung Cancer

Personalized therapy of advanced non-small cell lung cancer (NSCLC) has been improved by the introduction of EGFR tyrosine kinase inhibitors (TKIs), gefitinib and erlotinib. EGFR TKIs induce dramatic objective responses and increase survival in patients bearing sensitizing mutations in the EGFR intracytoplasmic tyrosine kinase domain. However, virtually all patients develop resistance, and this is responsible for disease relapse. Hence several efforts are being undertaken to understand the mechanisms of resistance in order to develop combination treatments capable to sensitize resistant cells to EGFR TKIs. Recent studies have suggested that upregulation of another member of the EGFR receptor family, namely ErbB3 is involved in drug resistance, through increased phosphorylation of its intracytoplasmic domain and activation of PI3K/AKT signaling. In this paper we first show, by using a set of malignant pleural effusion derived cell cultures (MPEDCC) from patients with lung adenocarcinoma, that surface ErbB3 expression correlates with increased AKT phosphorylation. Antibodies against ErbB3, namely A3, which we previously demonstrated to induce receptor internalization and degradation, inhibit growth and induce apoptosis only in cells overexpressing surface ErbB3. Furthermore, combination of anti-ErbB3 antibodies with EGFR TKIs synergistically affect cell proliferation in vitro, cause cell cycle arrest, up-regulate p21 expression and inhibit tumor growth in mouse xenografts. Importantly, potentiation of gefitinib by anti-ErbB3 antibodies occurs both in de novo and in ab initio resistant cells. Anti-ErbB3 mAbs strongly synergize also with the dual EGFR and HER2 inhibitor lapatinib. Our results suggest that combination treatment with EGFR TKI and antibodies against ErbB3 should be a promising approach to pursue in the clinic.