EGFR 19-Del上调Fn14及JAK/STAT的表达促进非小细胞肺癌的发生发展

目的：本研究检测Fn14、p-JAK1、p-STAT1在EGFR 19-Del的非小细胞肺癌(non-small cell lung cancer,NSCLC)细胞系中的表达,并探讨EGFR 19-Del对Fn14及JAK1/STAT1表达的调控作用,以期为EGFR 19-Del之NSCLC的发展机制研究奠定基础。方法：采用EGFR TKI(吉非替尼)处理HCC827细胞系(EGFR 19-Del)、H1975(L858R)及H292细胞系(正常肺上皮细胞),Western blot法检测Fn14、p-JAK1、p-STAT1蛋白表达。结果：相比于H1975和H292细胞系,Fn14、p-JAK1及p-STAT1基因和蛋白在HCC827细胞系中有较高的表达水平。对比未经吉非替尼处理的HCC827细胞系,经抑制剂处理后的HCC827细胞系中Fn14、p-JAK1、p-STAT1蛋白表达明显受到抑制,而在H292细胞系中无此现象。由此说明,EGFR 19-Del对Fn14及JAK/STAT信号分子的表达具有调控作用。结论：EGFR 19-Del可能通过上调Fn14及JAK/STAT信号分子的表达促进NSCLC的发生发展,而Fn14可能是EGFR 19-Del之NSCLC潜在的治疗靶点。     

Elevated expression of Fn14 in non-small cell lung cancer correlates with activated EGFR and promotes tumor cell migration and invasion

Lung cancer is the leading cause of cancer deaths worldwide; approximately 85% of these cancers are non-small cell lung cancer (NSCLC). Patients with NSCLC frequently have tumors harboring somatic mutations in the epidermal growth factor receptor (EGFR) gene that cause constitutive receptor activation. These patients have the best clinical response to EGFR tyrosine kinase inhibitors (TKIs). Herein, we show that fibroblast growth factor-inducible 14 (Fn14; TNFRSF12A) is frequently overexpressed in NSCLC tumors, and Fn14 levels correlate with p-EGFR expression. We also report that NSCLC cell lines that contain EGFR-activating mutations show high levels of Fn14 protein expression. EGFR TKI treatment of EGFR-mutant HCC827 cells decreased Fn14 protein levels, whereas EGF stimulation of EGFR wild-type A549 cells transiently increased Fn14 expression. Furthermore, Fn14 is highly expressed in EGFR-mutant H1975 cells that also contain an EGFR TKI-resistance mutation, and high TKI doses are necessary to reduce Fn14 levels. Constructs encoding EGFRs with activating mutations induced Fn14 expression when expressed in rat lung epithelial cells. We also report that short hairpin RNA-mediated Fn14 knockdown reduced NSCLC cell migration and invasion in vitro. Finally, Fn14 overexpression enhanced NSCLC cell migration and invasion in vitro and increased experimental lung metastases in vivo. Thus, Fn14 may be a novel therapeutic target for patients with NSCLC, in particular for those with EGFR-driven tumors who have either primary or acquired resistance to EGFR TKIs.     

Detection of low-level EGFR T790M mutation in lung cancer tissues

Epidermal growth factor receptor (EGFR) gene mutation status is critical to predicting responsiveness to EGFR tyrosine kinase inhibitor (TKI) therapies in non-small cell lung cancer (NSCLC) patients. However, a vast majority of the patients experience recurrence of the cancers by a secondary mutation of EGFR (T790M). Earlier studies suggested evidence that subclones bearing EGFR T790M mutation pre-exist in NSCLCs even prior to the therapies. However, to date, the status of T790M mutation in primary NSCLC is largely known. In this study, we developed an assay using peptide nucleic acid (PNA)-clamping PCR for detection of low-level EGFR T790M mutation. We found that the assay showed the highest sensitivity (0.01% mutation detection) in the clamping condition. We analyzed 147 NSCLC tissues [70 adenocarcinomas (AD), 62 squamous cell carcinomas (SQ), 12 large cell carcinomas (LC), and three adenosquamous carcinomas] that had not been exposed to the TKI therapies, and found 12 (8.2%; 12/147) EGFR T790M mutation in eight AD (11.4%), three SQ (4.8%), and one LC (8.3%) by the PNA-clamping PCR. However, this mutation was not detected by conventional DNA sequencing. Our data indicate that EGFR T790M exists in pretreatment NSCLC at low levels irrespective of histologic types. This study provides a basis for developing an applicable protocol for detecting low-level EGFR T790M mutation in primary NSCLC, which might contribute to predicting recurrence of the tumor in response to the TKI therapies.     

The age distribution of mortality due to influenza: pandemic and peri-pandemic

Background

The epidermal growth factor receptor (EGFR) is a validated therapeutic target in non-small cell lung cancer (NSCLC). However, current single agent receptor targeting does not achieve a maximal therapeutic effect, and some mutations confer resistance to current available agents. In the current study we have examined, in different NSCLC cell lines, the combined effect of RNA interference targeting the EGFR mRNA, and inactivation of EGFR signaling using different receptor tyrosine kinase inhibitors (TKIs) or a monoclonal antibody cetuximab.

Methods

NSCLC cells (cell lines HCC827, H292, H358, H1650, and H1975) were transfected with EGFR siRNA and/or treated with the TKIs gefitinib, erlotinib, and afatinib, and/or with the monoclonal antibody cetuximab. The reduction of EGFR mRNA expression was measured by real-time quantitative RT-PCR. The down-regulation of EGFR protein expression was measured by western blot, and the proliferation, viability, caspase3/7 activity, and apoptotic morphology were monitored by spectrophotometry, fluorimetry, and fluorescence microscopy. The combined effect of EGFR siRNA and different drugs was evaluated using a combination index.

Results

EGFR-specific siRNA strongly inhibited EGFR protein expression almost equally in all cell lines and inhibited cell growth and induced cell apoptosis in all NSCLC cell lines studied, albeit with a different magnitude. The effects on growth obtained with siRNA was strikingly different from the effects obtained with TKIs. The effects of siRNA probably correlate with the overall oncogenic significance of the receptor, which is only partly inhibited by the TKIs. The cells which showed weak response to TKIs, such as the H1975 cell line containing the T790M resistance mutation, were found to be responsive to siRNA knockdown of EGFR, as were cell lines with downstream TKI resistance mutations. The cell line HCC827, harboring an exon 19 deletion mutation, was more than 10-fold more sensitive to TKI proliferation inhibition and apoptosis induction than any of the other cell lines. Cetuximab alone had no relevant in vitro activity at concentrations obtainable in the clinic. The addition of EGFR siRNA to either TKIs or cetuximab additively enhanced growth inhibition and induction of apoptosis in all five cell lines, independent of the EGFR mutation status (wild-type or sensitizing mutation or resistant mutation). The strongest biological effect was observed when afatinib was combined with an EGFR-specific siRNA.

Conclusions

EGFR knockdown by siRNA further decreases the cell growth of lung cancer cells that are treated with TKIs or cetuximab alone, confirming that single agent drug targeting does not achieve a maximal biological effect. The siRNA inhibits EGFR oncogenic activity that bypasses downstream "resistance" mutations such as KRAS and PTEN. The combined treatment of siRNA and EGFR inhibitory agents is additive. The combination of a potent, irreversible kinase inhibitor such as afatinib, with EGFR-specific siRNAs should be further investigated as a new strategy in the treatment of lung cancer and other EGFR dependent cancers, including those with downstream resistance mutations.     

RAF1-MEK1-ERK/AKT axis may confer NSCLC cell lines resistance to erlotinib

The fact that advanced NSCLC patients with wild type (wt) EGFR can benefit from erlotinib therapy makes it critical to find out biomarkers for effective selection of patients and improving the therapy effects. In present study, 3 NSCLC cell lines (U1752, Calu-6 and NCI-H292) with wt EGFR and different sensitivities to erlotinib were used for microarray analysis. The differential basal gene expression between 2 NSCLC cell lines was analyzed, about 353 genes were expression-altered with higher than 2-fold changes between Calu-6 and U1752. And Ingenuity Pathway Analysis (IPA) showed that these genes were mainly enriched in regulation of epithelial–mesenchymal transition (EMT) pathway, Wnt-β catenin signaling, Tec kinase signaling and some types of cancer-related signaling. More interestingly, RAF1 (c-raf), MAP2K1 (MEK1), SNAI and downstream signaling molecules ERK and AKT were predicted to be activated in erlotinib-resistant cell line by IPA. Subsequent immunoblotting experiments showed that the phosphorylation of ERK and AKT were exactly increased stepwise from erlotinib sensitive cell line to erlotinib resistant cell lines. Collectively, activation of RAF1-MEK1-ERK/AKT axis may determine the resistance of NSCLC cell lines bearing wt EGFR to erlotinib. Our work provides potential biomarkers and therapeutic targets for NSCLC patients harboring wt EGFR.     

Expression of poly(C)-binding protein 1 (PCBP1) in NSCLC as a negative regulator of EMT and its clinical value

Poly (C)-binding Protein 1 (PCBP1) is a 35 kDa protein involved in a number of biological processes. Recently, the research found that PCBP1 might be involved in epithelial-mesenchymal transition (EMT). However, the role of PCBP1 in non-small-cell lung cancer (NSCLC) metastasis needs further elucidation. The purpose of this study was to determine whether PCBP1 could serve as a biomarker for stratification and prediction of prognosis in NSCLC as a regulator of EMT formation. In this study, PCBP1 expression was evaluated by Western blot in 8 fresh lung cancer tissues and immunohistochemistry (IHC) on 145 paraffin-embedded slices. PCBP1 was highly expressed in non-metastatic NSCLC specimens and significantly correlated with lymph node status (P < 0.001), clinical stage (P = 0.001), vimentin expression (P = 0.033) and E-cadherin expression (P = 0.042). Our study showed that the low expression of PCBP1 was correlated with decreased expression of E-cadherin and elevated expression of vimentin, which were the markers of EMT. Besides, high expression of PCBP1 was correlated with better prognosis. These findings suggested that PCBP1 might play an important role in preventing the process of EMT in NSCLC, thus be a promising therapeutic target to inhibit NSCLC metastasis.     

EGFR mutation L747P led to gefitinib resistance and accelerated liver metastases in a Chinese patient with lung adenocarcinoma

Background: Mutations in the epidermal growth factor receptor gene (EGFR) are found in around half of Asian patients with non-small cell lung cancer (NSCLC). For this reason, EGFR tyrosine kinase inhibitors (TKI) are often prescribed depending on the EGFR status. Two common EGFR mutations, a deletion in exon 19 and L858R in exon 21, demonstrate a positive response to gefitinib, the first approved EGFR TKI. However, T790M and an insertion in EGFR exon 21 are resistant to EGFR TKI treatment. The relationships between the EGFR mutation type and response to the target drug have not been fully investigated. Case presentation: We describe a 66-year-old Chinese male diagnosed with stage IV lung adenocarcinoma based on evidence from a computed tomography (CT) scan and histological features of a biopsy taken during fiberoptic bronchoscopy surgery. Molecular analysis of EGFR exons 19 and 21 revealed the presence of only one mutation in exon 19: L747P (2239-2240 TT>CC). The patient requested gefitinib treatment for 2 weeks but his response was poor. A CT scan revealed that the number and relative volume of the liver metastases had increased after treatment. Conclusion: L747P (2239-2240 TT>CC) in exon 19 is a rare EGFR mutation that appears to lead to gefitinib resistance and might accelerate liver metastases.     

Knockdown of TRIM66 inhibits malignant behavior and epithelial-mesenchymal transition in non-small cell lung cancer

Objective

The tripartite motif 66(TRIM66) is an important member of the TRIM protein superfamily, which can participate in the expression of multiple proteins, and is closely associated with the behaviors of non-small cell lung cancer (NSCLC). In this study, we aimed to explore the effect of TRIM66 in this process in vitro using NSCLC cell lines, and the role of TRIM66 in regulating epithelial-mesenchymal transition(EMT) in NSCLC.

受体酪氨酸激酶Axl高表达促进鼻咽癌临床进展

目的:探讨受体酪氨酸激酶anexelekto(Axl)在鼻咽癌(nasopharyngeal carcinoma,NPC)中的表达及意义。方法:采用免疫组化法检测78例NPC和32例鼻咽黏膜慢性炎中Axl的表达,分析Axl蛋白表达与NPC患者临床参数的相关性。常规培养NPC细胞,免疫荧光法检测不同分化NPC细胞系CNE1、CNE2Z及C666-1中Axl的蛋白表达情况。应用Axl特异性抑制剂TP-0903处理CNE1和C666-1细胞,CCK-8实验检测细胞的活力,流式细胞术检测细胞周期的分布,q PCR检测Axl和增殖细胞核抗原(PCNA)的mRNA表达,Western blot检测Axl及p-Axl蛋白的表达。结果:Axl蛋白定位于胞膜和胞质。NPC中Axl高表达阳性率显著高于鼻咽黏膜慢性炎(P0.01)。Axl高表达与患者年龄、性别及M分期无关,与临床分期、T分期和N分期呈正相关(P0.05)。Axl在高分化CNE1细胞中低表达,在低分化CNE2Z细胞和未分化C666-1细胞中表达水平明显增高。TP-0903呈浓度和时间依赖性抑制NPC细胞的活性,2 nmol/L TP-0903即具有显著抑制效应,能阻滞细胞周期于G0期,在降低Axl活性的同时也显著抑制PCNA的表达。结论:Axl高表达可促进NPC的临床进展;TP-0903显著抑制NPC细胞的增殖,提示Axl可能在NPC靶向治疗中具有一定的价值。     

Effects of long non-coding RNA (lncRNA) cancer susceptibility candidate 2c (CASC2c) on proliferation,metastasis and drug resistance of non-small cell lung cancer (NSCLC) cells through ERK1/2 and β-catenin signaling pathways

ObjectivesThis study was aimed to investigate the effects of long non-coding RNA (lncRNA) cancer susceptibility candidate 2c (CASC2c) on the proliferation, metastasis and drug resistance of non-small cell lung cancer (NSCLC) cells.MethodsThe expression of CASC2c in NSCLC tissues and cell lines was detected by real-time fluorescence quantitative PCR (RT-qPCR). MTT and Transwell assay were used to determine the proliferation and migration of NSCLC cells in the experimental group and the control group respectively. The drug sensitivity test was used to confirm whether increasing the CASC2c expression level could reverse the resistance of NSCLC cells to the chemotherapy drug cisplatin. The effects of CASC2c on the expression levels of p-ERK1/2 and β-catenin were detected by western blot.ResultsThe results of RT-qPCR showed that CASC2c was under-expressed in NSCLC tissues and cells compared with normal adjacent lung tissues cells (p < 0.05). In addition, the CASC2c expression was remarkably correlated with TNM staging, tumor cell differentiation, lymph node metastasis, smoking and other pathological indicators of patients with NSCLC (p < 0.05). MTT and Transwell assay showed that the high-expression of CASC2c significantly reduced the proliferation and migration of NSCLC cells compared to that of the control group (p < 0.05). Western blot assay showed that the high-expressed CASC2c can decrease the expression of phosphorylated-ERK1/2 (p-ERK1/2) and β-catenin.Conclusions: CASC2c was low expressed in NSCLC tissues and cells. What's more, it inhibited the proliferation and migration of NSCLC cells by inhibiting the expression of p-ERK1/2 and β-catenin and reversed NSCLC cells’ resistance to the chemotherapy drug cisplatin. Therefore, CASC2c may serve as a new biomarker and therapeutic target in the diagnosis and treatment of NSCLC.     

Clinical and molecular predictors of response to EGFR tyrosine kinase inhibitors in non-small cell lung cancer

Up to 10% of patients with non-small cell lung carcinoma (NSCLC) achieve an objective response to EGFR tyrosine kinase inhibitors (EGFR-TKI) such as erlotinib or gefitinib. This rate of response is related to non-smoker status, female gender, adenocarcinoma subtype, and Asian ethnicity. Molecular analysis showed that EGFR tyrosine kinase domain somatic mutations appear to be a strong predictor of response to EGFR-TKI. The L858R point mutation and the E746-A750 deletion represent 90% of the mutations encountered in responding patients. The amplification of EGFR gene also seems to be predictive of the response to EGFR-TKI, whereas T790M point mutation induces secondary resistance to EGFR-TKI. Nevertheless, objective responses or strong long-term stabilizations are observed in patients without any EGFR abnormality. Thus, the assessment of the EGFR status in patients with NSCLC remains controversial for clinical practice. The assessment of EGFR abnormalities should be targeted to identify reliable biomarkers of the NSCLC response to EGFR-TKI. This review presents the current knowledge on predictive biomarkers of NSCLC response to EGFR-TKI and the methods available for the assessment of EGFR status.     

EGFR-Mutationsanalyse beim nichtkleinzelligen Lungenkarzinom

Background

Some patients with non-small cell lung cancer (NSCLC) respond well to therapy with tyrosine kinase inhibitors (TKI). Somatic mutation of the epidermal growth factor receptor (EGFR) gene is an important predictive marker for TKI response.

Patients and methods

We performed EGFR mutation analysis in 307 NSCLC (exon 18-21). The data were analyzed for associations with clinical-pathological parameters.

Results

Relevant EGFR mutations were found in 25/307 NSCLC (8.1%; 178 biopsies and 129 cytologies). Most mutations were found in exon 19 (50%) followed by the L858R point mutation in exon 21 (12.5%). EGFR mutations were significantly more common in women than in men (16.8% vs. 2.7%; p<0.001) and in adenocarcinoma than in other carcinoma subtypes (11.4% vs. 3.8%; p=0.017). EGFR mutation was associated with TTF-1 positivity (p<0.041). Almost all (96%) mutated NSCLC were TTF-1 positive.

Conclusion

In Central Europe, the prevalence of relevant EGFR mutations in NSCLC is <10% of patients with NSCLC. EGFR mutations are more common in women and TTF-1 positive adenocarcinomas. Mutation analysis can be performed both from biopsies and cytologies.     

EGFR靶向药物治疗非小细胞肺癌的研究进展

在世界范围内,肺癌是死亡率最高的恶性肿瘤,其中以非小细胞肺癌(non-small cell lung cancer,NSCLC)为主.近年来,随着人表皮生长因子受体(epidermal growth factor receptor,EGFR)突变体的发现,以吉非替尼(gefitinib)和厄洛替尼(erlotinib)为代表的EGFR酪氨酸激酶抑制剂(EGFR-TKIs)对于携带有EGFR敏感突变的NSCLC具有良好的疗效.然而,耐药问题的出现增加了临床治疗的难度,针对非小细胞肺癌的EGFR靶向治疗,目前仍有很多问题亟待解决.本文现就EGFR靶向治疗的现状与发展进行综述.     

同期放化疗诱导人结直肠癌细胞发生上皮-间质转化

目的:探讨放化疗抵抗的结直肠癌细胞发生上皮-间质转化(epithelial-mesenchymal transition,EMT)的意义.方法:采用5-FU化疗同期进行放疗对人结直肠癌野生型细胞(HCTll6)进行干预,诱导放化疗共同抵抗的细胞株(HCT1 16CRR)并采用克隆形成实验进行放化疗抵抗性的鉴定.高倍显微镜下观察细胞形态学变化.采用Real-time PCR和Western印迹,检测上皮表型标志物E-cadherin,间质表型标志物N-cadherin、波形蛋白(vimentin)、核转录因子(Snail)mRNA及其蛋白的表达.结果:放化疗抵抗的结直肠癌细胞发生与EMT相符的形态学改变,细胞呈纺锤体状,极性消失,并出现伪足;Real-time PCR和Western印迹结果显示E-cadherin mRNA及蛋白表达下调;N-cadherin,vimentin,Snail mRNA及蛋白表达上调,差异有统计学意义(P＜0.05).结论:放化疗抵抗后的人结直肠癌细胞发生EMT,其与结直肠癌的治疗抵抗相关.     

Mig-6 overcomes gefitinib resistance by inhibiting EGFR/ERK pathway in non-small cell lung cancer cell lines

Non small cell lung cancer (NSCLC) accounts for 85% of all lung cancers and is the most common cause of lung cancer death. Currently, the epidermal growth factor receptor inhibitor gefitinib is widely used for patients with advanced NSCLC. However, drug resistance is a major obstacle. Mig-6 is a feedback inhibitor of EGFR and its down-stream pathway; it has been shown to play a role in gefitinib sensitivity. There is neither systematical research on the relationship between Mig-6 expression and gefitinib sensitivity, nor has the contribution of up-regulated Mig-6 on the gefitinib-resistant cell lines. In the present work, four NSCLC cell lines (H1299, A549, PC-9, and PC-9/AB11) with different sensitivities to gefitinib were subjected to analysis of the expression of Mig-6. We found that Mig-6 is over-expressed in gefitinib-sensitive NSCLC cell lines, but is low in gefitinib-resistant NSCLC cell lines. Further analysis revealed that over-expression of Mig-6 increased cell apoptosis and inhibited proliferation of gefitinib-resistant NSCLC cells treated with gefitinib, whereas lowering the expression of Mig-6 decreased cell apoptosis and promoted cell proliferation after treatment with gefitinib in gefitinib-sensitive NSCLC cell lines. These results suggest that Mig-6 is involved in mediating the response to gefitinib in NSCLC cell lines. Additionally we demonstrated that Mig-6 could reverse gefitinib resistance through inhibition of EGFR/ERK pathway in NSCLC cells. Our work uncovered that Mig-6 may be an effective therapeutic target in gefitinib-resistant lung cancer patients.     

Standardization of epidermal growth factor receptor (EGFR) measurement by quantitative immunofluorescence and impact on antibody-based mutation detection in non-small cell lung cancer

Challenges in measurement of epidermal growth factor receptor (EGFR) protein expression have led to conflicting data on its prognostic value and discontinuation of its use for prediction of response. Herein is described a quantitative standardized assay for EGFR and its use in a series of retrospective cohorts of patients with non-small cell lung cancer (NSCLC). The AQUA technology of quantitative immunofluorescence was used in conjunction with Western blot analysis to calculate the absolute concentration of EGFR in two independent NSCLC cohorts (170 from Yale New Haven Hospital and 335 from Sotiria and Patras Hospitals in Greece). EGFR and mutated EGFR were measured using D38B1 antibody and two mutation-specific antibodies. All patients positive or borderline for mutation-specific antibody were genotyped. A threshold for reproducible detection of EGFR was defined as 0.85 ng/μg total protein. EGFR expression demonstrated no prognostic value in either cohort. The mutation rate was 1.79% in the Yale cohort, and 1.52% in the Sotiria/Patras cohort, with no antibody detection-based false-positive cases. No mutations were detected for EGFR concentrations <1.46 ng/μg total protein. In summary, accurate measurement of EGFR still shows no prognostic value in NSCLC. In these two population-based cohorts, the antibody-based EGFR mutation rate was lower than has been frequently reported.     

肺癌患者外周血中EGFR-mRNA、LUNX-mRNA的表达及意义

目的建立以EGFR-mRNA、LUNX-mRNA为靶基因,逆转录聚合酶链反应(RT-PCR)检测肺癌患者肿瘤组织和外周血微转移的方法,探寻靶基因作为肺癌微转移检测分子标志物的可行性。方法应用RT-PCR技术检测40例非小细胞肺癌组织和15例肺良性病变组织中EGFR-mRNA、LUNX-mRNA的表达;检测40例肺癌患者外周血中靶基因的表达,并以15例良性肺疾病患者和10名健康人外周血作为对照。结果40例肺癌患者病理组织中EGFR-mRNA、LUNX-mRNA的表达率为77.5%(31/40)、100%(40/40),外周血中EGFR-mRNA、LUNX-mRNA表达阳性率为55.0%(22/40)、57.5%(23/40);对照组中,15例肺良性病变患者病理组织中EGFR-mRNA表达率为13.3%(2/15),无LUNX-mRNA表达,15例肺良性病变患者和10名健康人的外周血中无EGFR-mRNA、LUNX-mRNA表达。结论EGFR-mRNA、LUNX-mRNA是检测肺癌组织及肺癌外周血微转移的良好的分子标志物,两者表达与肺癌TNM分期和癌细胞分化程度关系密切。     

Lazertinib: on the Way to Its Throne

Lazertinib is an oral, irreversible, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that forms an irreversible covalent bond to the Cys797 residue in the ATP-binding site of the EGFR kinase domain and exhibits a high selectivity for sensitizing and T790M EGFR mutations. In January 2021, it was first approved for the treatment of advanced or metastatic non-small cell lung cancer (NSCLC) patients with EGFR T790M who had previously received EGFR TKI therapy based on LASER201, a phase I/II trial. At a recommended dose of 240 mg, lazertinib achieved an encouraging anti-tumor activity in both extra- and intracranial lesions. With a high half-maximal inhibitory concentration for EGFR wildtype tumors, it is anticipated to pose a lower risk of skin and cardiac adverse events compared to osimertinib. Lazertinib is currently being investigated as a monotherapy in first-line treatment and in combination with amivantamab under various settings. In this review, we systematically summarize the preclinical and clinical data of lazertinib and discuss future perspectives on the treatment of EGFR-mutant NSCLC.     

EphA2调控结直肠癌细胞耐药的初步研究

目的:探究Eph受体A2(Eph A2)在结直肠癌细胞化疗耐药中的作用及相关机制。方法:Western blot及real-time PCR检测人结肠癌细胞株Lo Vo及结肠癌耐药细胞株Lo Vo/5-FU中Eph A2的表达情况。转染Eph A2 siRNA干扰结肠癌耐药细胞株Lo Vo/5-FU中Eph A2的表达,CCK-8法检测细胞对化疗药物的敏感性,划痕实验及Transwell实验检测细胞迁移及侵袭能力的变化,Western blot检测上皮-间充质转化(EMT)及相关信号通路分子的蛋白水平。结果:耐药细胞株Lo Vo/5-FU中Eph A2的mRNA及蛋白表达水平均明显高于亲本细胞株(P0.05);并且在亲本细胞株Lo Vo中,Eph A2的蛋白表达水平随着5-FU浓度的增加有升高趋势。沉默Eph A2可降低结肠癌耐药细胞株Lo Vo/5-FU的细胞活力,增加其对化疗药物的敏感性,并抑制细胞的侵袭迁移;同时上调细胞中上皮细胞标志物E-cadherin和β-catenin的表达并下调间充质细胞标志物N-cadherin和vimentin的表达,可抑制结肠癌耐药细胞株Lo Vo/5-FU的EMT进程。此外,干扰Eph A2的表达之后,Notch和Snail的表达也明显降低。结论:沉默Eph A2可部分恢复结肠癌耐药细胞株Lo Vo/5-FU对化疗药物的敏感性,其机制可能与抑制细胞侵袭和迁移、同时通过Notch/Snail信号通路影响细胞的EMT进程有关。     

Molecular diagnostics of a single multifocal non-small cell lung cancer case using targeted next generation sequencing

Histological and molecular subtyping of non-small cell lung cancer (NSCLC) is important for predicting survival and drug response in these patients. Up to 8 % of NSCLC are multifocal and these tumor foci are often clonally related. Multiple foci can however also represent different primary tumors, with prognostic and therapeutic consequences. We describe a patient with multifocal NSCLC from which we obtained tissue from two separate lesions. With routine conventional molecular determinations, the clonal relationship between the two lesions was determined. In addition, targeted next generation sequencing with the Ion Torrent Personal Genome Machine (PGM) was performed to explore the accuracy and additional value of this relatively new technique. The two tumors of this patient showed different activating epidermal growth factor receptor (EGFR) mutations, EGFR amplification status, TP53 mutation status, and loss of heterozygosity patterns. With the PGM, all conventional detected mutations were confirmed, and an additional variant of unknown significance in ATM was detected in one of the tumors. The multifocal NSCLC of this patient represents two unrelated primary tumors. Our results suggest that multifocal NSCLC should be considered as potentially multiple primary tumors. As the presence of activating EGFR mutations has important therapeutic consequences, EGFR testing should be performed on all tumor foci present. In the present case, targeted next generation sequencing using the PGM appeared to be accurate and comparable with conventional molecular determinations. However, the application of the PGM in routine pathology molecular diagnostics needs validation in larger series of cases.