Clinical significance of EML4-ALK fusion gene and association with EGFR and KRAS gene mutations in 208 Chinese patients with non-small cell lung cancer

Hepatotoxicity of epidermal growth factor receptor - tyrosine kinase inhibitors (EGFR-TKIs)

Drug-induced liver injury (DILI) is one of the most frequently adverse reactions in clinical drug use, usually caused by drugs or herbal compounds. Compared with other populations, cancer patients are more prone to abnormal liver function due to primary or secondary liver malignant tumor, radiation-induced liver injury and other reasons, making potential adverse reactions from liver damage caused by anticancer drugs of particular concernduring clinical treatment process. In recent years, the application of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has changed the treatment status of a series of solid malignant tumors. Unfortunately, the increasing incidence of hepatotoxicitylimits the clinical application of EGFR-TKIs. The mechanisms of liver injury caused by EGFR-TKIs were complex. Despite more than a decade of research, other than direct damage to hepatocytes caused by inhibition of cellular DNA synthesis and resulting in hepatocyte necrosis, the rest of the specific mechanisms remain unclear, and few effective solutions are available. This review focuses on the clinical feature, incidence rates and the recent advances on the discovery of mechanism of hepatotoxicity in EGFR-TKIs, as well as rechallenge and therapeutic strategies underlying hepatotoxicity of EGFR-TKIs.

Comparing Genomic Profiles of ALK Fusion-Positive and ALK Fusion-Negative Nonsmall Cell Lung Cancer Patients

Background  Anaplastic lymphoma kinase ( ALK ) fusion events account for 3 to 7% of genetic alterations in patients with nonsmall cell lung cancer (NSCLC). This study aimed to explore the landscape of ALK fusion-positive and ALK fusion-negative in a large cohort of NSCLC patients. Methods  The formalin-fixed paraffin-embedded specimens of NSCLC patients who underwent next-generation sequencing from 2020 to 2023 in Yinfeng Gene Technology Co., Ltd. Clinical laboratory were included in this study. Results  In the current study, a total of 180 (3.20%) patients tested positive for ALK fusions in 5,622 NSCLC samples. Within the ALK -positive cohort, a total of 228 ALK fusions were identified. Furthermore, five novel ALK fusion partners, including DAB1-ALK , KCMF1-ALK , KIF13A-ALK , LOC643770-ALK , and XDH-ALK were identified. In cases with ALK fusion-positive, TP53 alterations were the most prevalent (26.3%), followed by CDKN2A (8.4%), epidermal growth factor receptor ( EGFR , 5.6%), and ALK (5.6%). By contrast, EGFR alterations were most prevalent (51%) in patients with ALK fusion-negative NSCLC, followed by TP53 (42.7%), KRAS (11.6%), and CDKN2A (11.3%). A total of 10 cases where ALK fusion co-occurred with EGFR mutations were also identified. Notably, the ALK fusion positivity rate was higher in younger patients ( p  < 0.0001) and in female patients ( p  = 0.0429). Additionally, positive ALK test results were more prevalent in patients with high programmed death-ligand 1 expression, especially when applying a 50% cutoff. Conclusions  Collectively, these findings offer valuable genomic insights that could inform the personalized clinical care of patients with NSCLC harboring ALK fusions within the context of precision medicine.

Cancer organoid-based diagnosis reactivity prediction (CODRP) index-based anticancer drug sensitivity test in ALK-rearrangement positive non-small cell lung cancer (NSCLC)

BACKGROUND

Recently, cancer organoid-based drug sensitivity tests have been studied to predict patient responses to anticancer drugs. The area under curve (AUC) or IC50 value of the dose-response curve (DRC) is used to differentiate between sensitive and resistant patient's groups. This study proposes a multi-parameter analysis method (cancer organoid-based diagnosis reactivity prediction, CODRP) that considers the cancer stage and cancer cell growth rate, which represent the severity of cancer patients, in the sensitivity test.

METHODS

On the CODRP platform, patient-derived organoids (PDOs) that recapitulate patients with lung cancer were implemented by applying a mechanical dissociation method capable of high yields and proliferation rates. A disposable nozzle-type cell spotter with efficient high-throughput screening (HTS) has also been developed to dispense a very small number of cells due to limited patient cells. A drug sensitivity test was performed using PDO from the patient tissue and the primary cancer characteristics of PDOs were confirmed by pathological comparision with tissue slides.

RESULTS

The conventional index of drug sensitivity is the AUC of the DRC. In this study, the CODRP index for drug sensitivity test was proposed through multi-parameter analyses considering cancer cell proliferation rate, the cancer diagnosis stage, and AUC values. We tested PDOs from eight patients with lung cancer to verify the CODRP index. According to the anaplastic lymphoma kinase (ALK) rearrangement status, the conventional AUC index for the three ALK-targeted drugs (crizotinib, alectinib, and brigatinib) did not classify into sensitive and resistant groups. The proposed CODRP index-based drug sensitivity test classified ALK-targeted drug responses according to ALK rearrangement status and was verified to be consistent with the clinical drug treatment response.

CONCLUSIONS

Therefore, the PDO-based HTS and CODRP index drug sensitivity tests described in this paper may be useful for predicting and analyzing promising anticancer drug efficacy for patients with lung cancer and can be applied to a precision medicine platform.

Bevacizumab biosimilar candidate TAB008 compared to Avastin® in patients with locally advanced, metastatic EGFR wild-type non-squamous non-small cell lung cancer: a randomized, double-blind, multicenter study

BACKGROUND

Bevacizumab (Avastin®) is a monoclonal antibody targeting the vascular endothelial growth factor (VEGF). Used alone or in combination with chemotherapy and/or immunotherapy, Avastin® has shown promising efficacy in many cancers. This study compared the efficacy and safety of TAB008 with Avastin® sourced from the EU (bevacizumab-EU), in patients with non-squamous non-small cell lung cancer (nsNSCLC).

METHOD

In this randomized, double-blind, multicenter, phase III similarity study, treatment naïve for metastatic lung cancer., EGFR wild-type, locally advanced, metastatic, or recurrent non-squamous, non-small cell, lung cancer (nsNSCLC) patients were enrolled and randomized (1:1) into TAB008 or Avastin® groups. Patients received TAB008 or Avastin® 15 mg/kg intravenously plus paclitaxel/carboplatin for 4-6 cycles followed by TAB008 or Avastin® 7.5 mg/kg until disease progression, unacceptable toxicity or death. The primary endpoint compared the objective response rate (ORR) within 6 cycles as read by an independent radiological review committee (IRRC). Secondary endpoints compared disease control rate (DCR) Within 6 cycles, duration of response (DoR), progression-free survival (PFS), a year overall survival rate (OSR), overall survival (OS), safety, immunogenicity, and steady-state pharmacokinetics.

RESULTS

A total of 549 nsNSCLC patients were enrolled (277 in TAB008 group and 272 in Avastin® group). In the full analysis set, ORRs were 55.957% for TAB008 and 55.720% for Avastin®, and the ORR ratio was 1 (90% CI 0.89-1.14), well within the predefined equivalence margin of 0.75-1.33. No significant differences were found in DCR within 6 cycles (95.703% vs 95.367%, p = 0.8536), DoR (8.17 vs 7.3 months, p = 0.3526), PFS (9.10 vs. 7.97 months, p = 0.9457), 1 year overall survival rate (66.2% vs 68%, p = 0.6793), or OS (20.4 vs 17.6 months, p = 0.6549). Serious adverse events (SAEs) occurred in 37.55% (104/277) of patients in the TAB008 group and 34.32% (93/271) in the Avastin® group. Anti-drug antibodies were reported in 3 of 277 (1.08%) TAB008 patients, and 5 of 271 (1.85%) Avastin® patients, neutralizing antibody (Nab) was positive in 1 patient on Avastin®, which became negative upon follow-up. The steady-state trough concentrations (Cssmin) were 106.13 μg/mL in TAB008 group and 96.03 μg/mL in Avastin® groups, with the treatment group ratio of LS geometric means fully contained within the bioequivalence limits of 80.00-125.00% (90% CI was 101.74-120.05%).

CONCLUSIONS

TAB008 is similar to Avastin® in terms of efficacy, safety, and pharmacokinetic parameters, with comparable immunogenicity.

TRIAL REGISTRATION

ClinicalTrials.gov number; NCT05427305.

Identification of novel prognostic risk signature of breast cancer based on ferroptosis-related genes

Ferroptosis is a type of cell regulated necrosis triggered by intracellular phospholipid peroxidation, which is more immunogenic than apoptosis. Therefore, genes controlling ferroptosis may be promising candidate biomarkers for tumor therapy. In this study, we investigate the function of genes associated with ferroptosis in breast cancer (BC) and systematically evaluate the relationship between ferroptosis-related gene expression and prognosis of BC patients from the Cancer Genome Atlas database. By using the consensus clustering method, 1203 breast cancer samples were clustered into two clearly divided subgroups based on the expression of 237 ferroptosis-related genes. Then differentially expressed analysis and least absolute shrinkage and selection operator were used to identify the prognosis-related genes. Furthermore, the genetic risk signature was constructed using the expression of prognosis-related genes. Our results showed that the genetic risk signature can identify patient subgroups with distinct prognosis in either training cohort or validation, and the genetic risk signature was associated with the tumor immune microenvironment. Finally, the Cox regression analysis indicated that our risk signature was an independent prognostic factor for BC patients and this signature was verified by the polymerase chain reaction and western blot. Within this study, we identified a novel prognostic classifier based on five ferroptosis-related genes which may provide a new reference for the treatment of BRCA patients.

Discovery of clinically relevant fusions in pediatric cancer

Background

Pediatric cancers typically have a distinct genomic landscape when compared to adult cancers and frequently carry somatic gene fusion events that alter gene expression and drive tumorigenesis. Sensitive and specific detection of gene fusions through the analysis of next-generation-based RNA sequencing (RNA-Seq) data is computationally challenging and may be confounded by low tumor cellularity or underlying genomic complexity. Furthermore, numerous computational tools are available to identify fusions from supporting RNA-Seq reads, yet each algorithm demonstrates unique variability in sensitivity and precision, and no clearly superior approach currently exists. To overcome these challenges, we have developed an ensemble fusion calling approach to increase the accuracy of identifying fusions.

Results

Our Ensemble Fusion (EnFusion) approach utilizes seven fusion calling algorithms: Arriba, CICERO, FusionMap, FusionCatcher, JAFFA, MapSplice, and STAR-Fusion, which are packaged as a fully automated pipeline using Docker and Amazon Web Services (AWS) serverless technology. This method uses paired end RNA-Seq sequence reads as input, and the output from each algorithm is examined to identify fusions detected by a consensus of at least three algorithms. These consensus fusion results are filtered by comparison to an internal database to remove likely artifactual fusions occurring at high frequencies in our internal cohort, while a “known fusion list” prevents failure to report known pathogenic events. We have employed the EnFusion pipeline on RNA-Seq data from 229 patients with pediatric cancer or blood disorders studied under an IRB-approved protocol. The samples consist of 138 central nervous system tumors, 73 solid tumors, and 18 hematologic malignancies or disorders. The combination of an ensemble fusion-calling pipeline and a knowledge-based filtering strategy identified 67 clinically relevant fusions among our cohort (diagnostic yield of 29.3%), including RBPMS-MET, BCAN-NTRK1, and TRIM22-BRAF fusions. Following clinical confirmation and reporting in the patient’s medical record, both known and novel fusions provided medically meaningful information.

Conclusions

The EnFusion pipeline offers a streamlined approach to discover fusions in cancer, at higher levels of sensitivity and accuracy than single algorithm methods. Furthermore, this method accurately identifies driver fusions in pediatric cancer, providing clinical impact by contributing evidence to diagnosis and, when appropriate, indicating targeted therapies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-08094-z.

Genetic and treatment profiles of patients with concurrent Epidermal Growth Factor Receptor (EGFR) and Anaplastic Lymphoma Kinase (ALK) mutations

Background

EGFR and ALK alternations often contribute to human malignancies, including lung cancer. EGFR and ALK mutations are usually sensitive to EGFR-tyrosine kinase inhibitors (TKIs) and ALK-TKIs. Although generally mutually exclusive, these mutations do co-exist in rare cases. This study investigated the frequencies, clinical characteristics, therapeutic efficacies, and genetic profiles of lung cancer patients with EGFR and ALK co-mutations.

Methods

Patients with concurrent EGFR and ALK mutations were included in this study, which analyzed mutation profiles and treatment histories. SPSS20.0 were used for survival analysis.

Results

Among 271 ALK-positive (ALK-pos) and 2975 EGFR-positive (EGFR-pos) patients in our database, nine (2.6% of ALK-pos and 0.2% of EGFR-pos) patients had concurrent EGFR and ALK mutations (including three exon19 Indel + EML4-ALK, two exon19 Indel + STRN-ALK, two L858R + L1152R, one L858R + EML4-ALK, and one G719C + S768I + STRN-ALK). Eight patients had at least one type of EGFR-TKIs treatment. The median progression free survival (PFS) of these patients on first-generation EGFR-TKIs was 14.5 months (95% CI: 11 - NR). Of these eight patients, one who progressed on Gefitinib and subsequently on Osimertinib had a T790M + C797G. The other seven EGFR-TKIs resistance patients had no known resistance mutations. No patients had ALK mutations before treatment, so ALK mutations may have developed as resistance mechanisms during EGFR-TKIs therapies. EGFR-TKIs-treated patients with EGFR/ALK L1152R mutations generally had a shorter PFS than patients with other mutation combinations.

Conclusions

ALK and EGFR mutations coincide at a relatively low frequency in lung cancer patients. ALK mutations developed either synchronously or heterochronously with EGFR mutations. Two ALK mutations (L1152R and STRN-ALK) may co-exist with EGFR mutations at a higher frequency than others. Most EGFR/ALK co-alteration patients (other than the EGFR/ALK L1152R type) can benefit from first line EGFR-TKIs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08824-2.

Development of a novel ALK rearrangement screening test for non-small cell lung cancers

Approximately 5–7% of non–small cell lung cancer (NSCLC) cases harbor an anaplastic lymphoma kinase (ALK) fusion gene and may benefit from ALK inhibitor therapy. To detect ALK fusion genes, we developed a novel test using reverse transcription polymerase chain reaction (RT-PCR) for the ALK kinase domain (KD). Since ALK expression is mostly silenced in the adult with the exception of neuronal tissue, the normal lung tissue, mesothelial lining, and inflammatory cells are devoid of ALK transcript, making ALK KD RT-PCR an ideal surrogate test for ALK fusion transcripts in lung or pleural effusion. The test was designed with a short PCR product (197 bp) to work for both malignant pleural effusion (MPE) and formalin-fixed, paraffin-embedded (FFPE) NSCLC samples. Using ALK IHC as a reference, the sensitivity of the test was 100% for both MPE and FFPE. The specificity was 97.6% for MPE and 97.4% for FFPE. Two false positive cases were found. One was a metastatic brain lesion which should be avoided in the future due to intrinsic ALK expression in the neuronal tissue. The other one resulted from ALK gene amplification. Due to potential false positivity, subsequent confirmation tests such as fluorescence in situ hybridization or multiplex PCR would be preferable. Nevertheless, the test is simple and inexpensive with no false negativity, making it a desirable screening test. It also offers an advantage over multiplex RT-PCR with the capability to detect novel ALK fusions. Indeed through the screening test, we found a novel ALK fusion partner (sperm antigen with calponin homology and coiled-coil domains 1 like gene, SPECC1L) with increased sensitivity to crizotinib in vitro. In summary, a novel RNA-based ALK KD analysis was developed for ALK rearrangement screening in MPE and FFPE specimens of NSCLC. This simple inexpensive test can be implemented as routine diagnostics.

Deep proteogenomic investigations elucidate the NRF2 antioxidant mechanism as a major driving mechanism of lung adenocarcinoma in Asia

BACKGROUND

Lung adenocarcinoma is a global leading cause of death. Despite modern therapeutic interventions, undesirable outcomes such as drug resistances and disease recurrence still occur. Therefore, continued investigations of disease driving mechanisms and counteracting strategies are urgently needed.

METHODS

We re-visited two deep-proteogenomic resources of lung adenocarcinoma published recently. These resources were derived from patient cohorts with decent sizes in Taiwan and China. The gene set enrichment analysis (GSEA) was performed. A heatmap was produced by the generalized association plot (GAP).

RESULTS

Among 189 common oncogenic pathways investigated, the nuclear factor erythroid 2-related factor 2 (NRF2) downstream antioxidant mechanism was uncovered for the first time the leading oncogenic mechanism of lung adenocarcinoma in Taiwan. The gene levels of NRF2 (also known as NFE2L2) is negatively correlated with those of KEAP1 (Pearson's correlation = -0.275, p = 0.009) in patients' tumor tissues. Furthermore, the protein levels of EIF2S2 and PGD are higher in patients with more advanced stages in the Taiwan cohort (p = 0.001 and 0.05, respectively), and are indicative of poorer progression-free survival (PFS) and overall survival (OS) in the China cohort (all Cox-regression p < 0.05). On the other hand, EPHX1 is higher in patients with earlier stages in Taiwan (p = 0.003), and are indicative of better PFS and OS in China (both Cox-regression p < 0.05). When the patients were stratified using the median protein abundances for Kaplan-Meier visualizations, patient strata with higher EIF2S2, PGD, and EPHX1 have significantly poorer PFS (log-rank p = 0.041); poorer OS (p = 0.006), and better PFS and OS (p = 0.001 and 0.030), respectively.

CONCLUSION

The NRF2 downstream antioxidant mechanism is one major driving mechanism of lung adenocarcinoma in Asia, and represents important directions for future therapeutic interventions. Major downstream proteins such as EIF2S2, PGD, and EPHX1 are indicative of cancer stages and prognosis.

Driver and novel genes correlated with metastasis of non-small cell lung cancer: A comprehensive analysis

Although mutations of genes are crucial events in tumorigenesis and development, the association between gene mutations and lung cancer metastasis is still largely unknown. The goal of this study is to identify driver and novel genes associated with non-small cell lung cancer (NSCLC) metastasis. Candidate genes were identified using a novel comprehensive analysis, which was based on bioinformatics technology and meta-analysis. Firstly, EGFR, KRAS, ALK, TP53, BRAF and PIK3CA were identified as candidate driver genes. Further meta-analysis identified that EGFR (Pooled OR 1.33, 95% CI 1.19, 1.50; P < .001) and ALK (Pooled OR 1.52, 95% CI 1.22, 1.89; P < .001) mutations were associated with distant metastasis of NSCLC. Besides, ALK (Pooled OR 2.40, 95% CI 1.71, 3.38; P < .001) mutation was associated with lymph node metastasis of NSCLC. In addition, thirteen novel gene mutations were identified to be correlated with NSCLC metastasis, including SMARCA1, GGCX, KIF24, LRRK1, LILRA4, OR2T10, EDNRB, NR1H4, ARID4A, PRKCI, PABPC5, ACAN and TLN1. Furthermore, elevated mRNA expression level of SMARCA1 and EDNRB was associated with poor overall survival in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC), respectively. Additionally, pathway and protein-protein interactions network analyses found the two genes were correlated with epithelial-mesenchymal transition process. In conclusion, mutations of EGFR and ALK were significantly correlated with NSCLC metastasis. In addition, thirteen novel genes were identified to be associated with NSCLC metastasis, especially SMARCA1 in LUAD and EDNRB in LUSC.

EML4-ALK-mediated activation of the JAK2-STAT pathway is critical for non-small cell lung cancer transformation

BACKGROUND

The echinoderm microtubule-associated protein-like-4 anaplastic lymphoma kinase (EML4-ALK) fusion gene was identified in a subset of non-small cell lung cancer (NSCLC) patients. They responded positively to ALK inhibitors. This study aimed to characterize the mechanisms triggered by EML4-ALK to induce NSCLC transformation.

METHODS

HEK293 and NIH3T3 cells were transfected with EML4-ALK variant 3 or pcDNA3.1-NC. H2228 cells were transfected with siRNA-EML4-ALK or siRNA-NC. Cell viability and proliferation were measured by the CCK-8 and EdU methods, respectively. Flow cytometry revealed apoptosis. Gene expression profiles were generated from a signaling pathway screen in EML4-ALK-regulated lung cancer cells and verified by qPCR and Western blotting. The co-immunoprecipitation and immunohistochemistry/ immunofluorescence determined the interaction and colocalization of JAK2-STAT pathway components with EML4-ALK.

RESULTS

Microarray identified several genes involved in the JAK2-STAT pathway. JAK2 and STAT6 were constitutively phosphorylated in H2228 cells. EML4-ALK silencing downregulated phosphorylation of STAT6. Expression of EML4-ALK in HEK293 and NIH3T3 cells activated JAK2, STAT1, STAT3, STAT5, and STAT6. In EML4-ALK-transfected HEK293 cells and EML4-ALK-positive H2228 cells, activated STAT6 and JAK2 colocalized with ALK. STAT3 and STAT6 were phosphorylated and translocated to the nucleus of H2228 cells following IL4 or IL6 treatment. Apoptosis increased, while cell proliferation and DNA replication decreased in H2228 cells following EML4-ALK knockdown. In contrast, HEK293 cell viability increased following EML4-ALK overexpression, while H2228 cell viability significantly decreased after treatment with ALK or JAK-STAT pathway inhibitors.

CONCLUSIONS

Our data suggest that the aberrant expression of EML4-ALK leads to JAK2-STAT signaling pathway activation, which is essential for the development of non-small cell lung cancer.

Genotyping Squamous Cell Lung Carcinoma in Colombia (Geno1.1-CLICaP)

Background

Lung cancer is a public health problem, and squamous cell carcinoma (SCC) is the second most prevalent subtype of this neoplasm. Compared to other subtypes, including adenocarcinoma, SCC is less well understood in terms of molecular pathogenesis, limiting therapeutic options among targeted agents approved for other disease subgroups. In this study, we sought to characterize the SCC genomic profile using a validated Next Generation Sequencing (NGS) platform.

Methods

The comprehensive NGS assay (TruSight Tumor 170) was used in order to target the full coding regions of 170 cancer-related genes on SCC samples. PD-L1 expression in tumor cells (TCs) was assessed using clone 22C3 (Dako). Clinical outcomes were correlated with molecular profile, including progression free survival (PFS), overall response rate (ORR), and overall survival (OS).

Results

A total of 26 samples were included, median age was 67 years (r, 33–83) and 53.8% were men. Tobacco consumption was identified in all subjects (mean 34-year package). For first-line treatment 80.8% of patients received cisplatin or carboplatin plus gemcitabine. In terms of molecular profile, we identified a high prevalence of inactivating mutations in TP53 (61.5%), PIK3CA (34.6%), MLL2 (34.6%), KEAP1 (38.4%), and NOTCH1 (26.9%). PD-L1 expression ranged from negative, 1, 2–49, and ≥50% in 23.1, 38.5, 26.9, and 11.5%, respectively. Interestingly, the genetic alterations did not have an effect in PFS, OS or ORR in this study. However, PDL1 expression was higher among those who had mutations in TP53 (p = 0.037) and greater expression of PDL1 was related to PIK3CA alterations (p = 0.05).

Conclusions

The genomic profile of SCC encompasses important genes including TP53, PIK3CA and KEAP1. TP53 mutations could be associated with PDL1 expression, generating hypothesis regarding specific treatment options.

Catalog of Lung Cancer Gene Mutations Among Chinese Patients

Background: Detailed catalog of lung cancer-associated gene mutations provides valuable information for lung cancer diagnosis and treatment. In China, there has never been a wide-ranging study cataloging lung cancer-associated gene mutations. This study aims to reveal a comprehensive catalog of lung cancer gene mutations in china, focusing on EGFR, ALK, KRAS, HER2, PIK3CA, MET, BRAF, HRAS, and CTNNB1 as major targets. Additionally, we also aim to correlate smoking history, gender, and age distribution and pathological types with various types of gene mutations. Patients and Methods: A retrospective data acquisition was conducted spanning 6 years (2013-2018) among all patients who underwent lung cancer surgeries not bronchial or percutaneous lung biopsy at three major tertiary hospitals. Finally, we identified 1,729 patients who matched our inclusion criteria. Results: 1081 patients (62.49%) harbored EGFR mutation. ALK (n = 42, 2.43%), KRAS (n = 201, 11.62%), CTNNB1 (n = 28, 1.62%), BRAF (n = 31, 1.79%), PIK3CA (n = 51, 2.95%), MET (n = 14, 0.81%), HER2 (n = 47, 2.72%), HRAS (n = 3, 0.17%), and other genes(n = 232, 13.4%). Females expressed 55.38% vs. males 44.62% mutations. Among subjects with known smoking histories, 32.82% smokers, 67.15% non-smokers were observed. Generally, 51.80% patients were above 60 years vs. 48.20% in younger patients. Pathological types found includes LUADs 71.11%, SQCCs 1.68%, ASC 0.75%, LCC 0.58%, SCC 0.35%, ACC 0.17%, and SC 0.06%, unclear 25.19%. Conclusion: We offer a detailed catalog of the distribution of lung cancer mutations. Showing how gender, smoking history, age, and pathological types are significantly related to the prevalence of lung cancer in China.

Correlation between pre-treatment serum carcinoembryonic antigen levels and genotypes in a large population of Chinese people with advanced lung adenocarcinoma

BACKGROUND

A positive correlation between serum carcinoembryonic antigen (CEA) levels and epidermal growth factor receptor (EGFR) mutations has been reported in lung adenocarcinoma patients.

AIM

To investigate retrospectively whether serum CEA levels are also associated with genotypes in a large population of advanced lung adenocarcinoma.

METHODS

A large cohort of 701 patients with advanced lung adenocarcinoma was studied retrospectively.

RESULTS

EGFR mutations were found in 47.5% (333/701) of advanced lung adenocarcinoma patients, being identified at high frequencies in never-smokers, females, and in patients with abnormal pre-treatment serum CEA levels (53.1% vs 37.5%, P < 0.001). In contrast, anaplastic lymphoma kinase gene rearrangements were found in 7.8% (55/701) of patients, being identified at high frequencies in younger patients, and in patients with normal CEA levels (11.5% vs 5.8%, P = 0.012). Serum CEA levels were divided into four groups: <5, 5-19, 20-99 and ≥100 ng/mL. The rate of EGFR mutations significantly increased as the serum CEA levels increased (37.5%, 49.5%, 53.9% and 57.7%, respectively, P < 0.001). Anaplastic lymphoma kinase gene rearrangements showed the opposite result (11.5%, 7.1%, 5.7% and 4.1%, respectively, P = 0.044). A multivariate analysis revealed that higher pre-treatment serum CEA levels were independently associated with EGFR mutations (95% CI: 1.291-2.487, P < 0.001), but normal serum CEA levels were independently associated with anaplastic lymphoma kinase gene rearrangements (95% CI: 0.275-0.842, P = 0.010).

CONCLUSION

Our study demonstrated that a significant association exists between the serum CEA levels and genotypes in patients with advanced lung adenocarcinoma.

Comparison of EML4-ALK fusion gene positive rate in different detection methods and samples of non-small cell lung cancer

Objective: To evaluate differences of EML4-ALK positive rates in tissues samples between immunohistochemistry, reverse transcriptase polymerase chain reaction and the next-generation sequencing method. Besides, to compare the differences of EML4-ALK positive rates in blood samples and tissue samples by next-generation sequencing. The results provide a basis for the selection of a suitable EML4-ALK fusion gene detection method. Methods: Immunohistochemistry analysis of EML4-ALK in tumors was performed on samples from 2631 patients with non-small cell lung cancer. The mutation of EML4-ALK in the tissue samples of 399 patients with non-small cell lung cancer was detected by reverse transcription polymerase chain reaction. Next-generation sequencing was used to detect the mutation of EML4-ALK in 1505 non-small cell lung cancer patients, including 1208 tissue samples and 297 blood samples. Results: The positive incidence of EML4-ALK by immunohistochemistry was 7.11% (187/2631). Histologically, 9.51% (170/1787) of the samples were lung adenocarcinomas, and 2.01% (17/844) were squamous cell carcinomas. The positive rate of EML4-ALK was 8.52% (34/399) in 399 patients with non-small cell lung cancer, as detected by reverse transcription polymerase chain reaction; the mutation rate of adenocarcinoma was 11.62% (33/284), and the mutation rate of squamous cell carcinoma was 0.86% (1/115). In 1208 patients with non-small cell lung cancer with tissue samples, the positive rate of EML4-ALK was 4.88% (59/1208), as determined by next-generation sequencing, the mutation rate of adenocarcinoma was 5.84% (58/994), and the mutation rate of squamous cell carcinoma was 0.47% (1/214). The positive rate of EML4-ALK detected by reverse transcription polymerase chain reaction was higher than that detected by immunohistochemistry. Compared with the next-generation sequencing results, the positive rates of EML4-ALK detected by immunohistochemistry and reverse transcription polymerase chain reaction were higher, and the differences were significant (p<0.05). In blood samples from 297 patients with non-small cell lung cancer, the positive rate of EML4-ALK detected by next-generation sequencing was 3.70% (11/297), the mutation rate of adenocarcinoma was 3.82% (10/262), and the mutation rate of squamous cell carcinoma was 2.86% (1/35). The EML4-ALK positive rate of the tissue samples was thus higher than that of the blood biopsy samples. Conclusion: Among the three methods for detecting EML4-ALK, reverse transcription polymerase chain reaction has the highest positive rate, followed by immunohistochemistry, and next-generation sequencing has the lowest positive rate. The positive detection rate of EML4-ALK in tissue samples by next-generation sequencing was higher than that in blood samples.

Molecular and clinical analysis of Chinese patients with anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer

Anaplastic lymphoma kinase (ALK) fusions have been recognized as a therapeutic target in non‐small cell lung cancer (NSCLC). However, molecular signatures and clinical characteristics of the Chinese population with ALK‐rearranged NSCLC are not well elucidated. In the present study, we carried out targeted next‐generation sequencing on tissue and plasma ctDNA samples in 1688 patients with NSCLC. Overall, ALK fusions were detected in 70 patients (4.1%), and the frequencies of ALK fusions detected in tissue and plasma samples were 5.1% and 3.3%, respectively. Additionally, the prevalence of breakpoint locations for EML4‐ALK fusions in ctDNA was significantly correlated with that in tumor tissues (R² = .91, P = .045). According to age, the incidence rates of ALK fusions among young (age <45 years), middle‐aged (between 45 and 70 years) and elderly (>70 years) patients were significantly different (P < .001). In 70 ALK‐rearranged cases, coexistence of epidermal growth factor receptor (EGFR) alterations and ALK fusions was detected in 12 cases (17.1%) and EGFR mutations tended to coexist with non‐EML4‐ALK rearrangements. Notably, novel ALK fusion partners, including TRIM66,SWAP70,WNK3,ERC1,TCF12 and FBN1 were identified in the present study. Among EML4‐ALK fusion variants, patients with variant V1 were younger than patients with variant V3 (P = .023), and TP53 mutations were more frequently concurrent with variant V3 compared with variant V1 (P = .009). In conclusion, these findings provide new insights into the molecular‐clinical profiles of patients with ALK‐rearranged NSCLC that may improve the treatment strategy of this population.

Elevated levels of pre-treatment lactate dehydrogenase are an unfavorable predictor factor in patients with EML4-ALK rearrangement non-small cell lung cancer treated with crizotinib

Background

Targeted therapy is an important treatment for advanced non-small cell lung cancer (NSCLC) patients with specific genetic mutations, crizotinib can prolong survival in advanced NSCLC patients with echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) rearrangement. We performed a retrospective analysis to investigate the association between the lactate dehydrogenase (LDH) levels and progression-free survival (PFS) in patients with EML4-ALK rearrangement NSCLC receiving treatment with crizotinib.

Methods

Advanced (stage IIIb-IV) NSCLC patients with EML4-ALK rearrangement receiving treatment with crizotinib were enrolled between January 2007 and January 2016 at Peking Union Medical College and Cancer Hospital Chinese Academy of Medical Sciences.

Results

Overall, 212 patients were enrolled. Kaplan-Meier univariate analysis showed that elevated pre-treatment LDH level (7.9 vs 14.1 months, HR =1.251, CI: 1.008-1.553, P=0.004) was significantly associated with shorter PFS, while the post-treatment mean-LDH level (13.3 vs 14.3 months, HR=1.439, 95% CI: 0.994-2.082, P=0.970) was not significantly associated with PFS. Cox proportional hazards model also identified that pre-treatment LDH level (HR=2.085, 95% CI: 1.150-3.781, P=0.016) was associated with the PFS. Logistic regression analysis showed that post-treatment LDH level was associated with creatine kinase (OR=6.712, 95% CI 3.395-13.273, P<0.01), creatine kinase isoenzyme (OR=6.297, 95% CI 2.953-13.427, P<0.01), and hemoglobin (OR=4.163, 1.741-9.956, P<0.001).

Conclusion

An elevated pre-treatment serum LDH level (>250 U/L) was significantly associated with shorter PFS in patients with EML4-ALK rearrangement NSCLC. Post-treatment elevated serum LDH level was not significantly associated with PFS, which related to adverse events including muscle damage and anemia.

Chinese perspectives on clinical efficacy and safety of alectinib in patients with ALK-positive advanced non-small cell lung cancer

The incidence of lung cancer is increasing in China, in contrast to trends in Western countries, due to the increasing numbers of smokers and high levels of air pollution. Non-small-cell lung cancer (NSCLC) is the most common form of lung cancer, accounting for approximately 85% of lung cancers. Better understanding of the pathogenesis of NSCLC has led to the identification of multiple genetic mutations and chromosomal translocations such as those in the anaplastic lymphoma kinase (ALK) gene. To facilitate the identification of treatment targets, multiple guidelines (European Society for Medical Oncology, National Comprehensive Cancer Network, and American Society of Clinical Oncology) now recommend screening for genetic factors to help guide treatment decisions. In recent years, multiple ALK inhibitors have been developed to treat NSCLC, including the first-generation tyrosine kinase inhibitor (TKI) crizotinib; second-generation TKIs such as ceritinib, ensartinib, brigatinib, and alectinib; the third-generation TKI lorlatinib; and the fourth-generation TKI repotrectinib. These agents differ in structure, potency, and activity, both systemically and their effects on central nervous system (CNS) metastases. Recently, alectinib was approved in China to treat patients with locally advanced or metastatic NSCLC that were ALK+. Alectinib has demonstrated activity against NSCLC, including metastases within the CNS, with better tolerability than crizotinib. These ALK inhibitors represent significant advances in the treatment of NSCLC and yet patients will likely still exhibit disease progression. Alectinib offers greater potency with greater specificity as well as a better toxicity profile than many other TKIs that are currently available. Here, we review the role of ALK as a therapeutic target in NSCLC, the testing methods for identifying ALK-rearranged NSCLC, and the various TKIs currently being used or explored for treatment in this setting, with a focus on alectinib from a Chinese perspective.

The prevalence of EML4-ALK variants in patients with non-small-cell lung cancer: a systematic review and meta-analysis

To investigate the prevalence of EML4-ALK variants in non-small-cell lung cancer (NSCLC) patients. Materials & methods: Database of Pubmed, Embase, Medline and Cochrane Library were searched systematically to April 2018. Results: A total of 39 articles including 1903 NSCLC patients with ALK positive were recruited. The overall pooled prevalence for EML4-ALK variant 1 to 3 was 81.84% (95% CI: 76.68-86.99%), ranging from 86.64% tested by RT-PCR to 70.85% tested by other methods (p = 0.00). Subgroup analysis showed that the pooled prevalences of variant 1, 2 and 3 were 40.38% (95% CI: 34.83-45.93%), 6.59% (95% CI: 4.27-8.91%) and 26.54% (95% CI: 20.89-32.2%), respectively. Conclusion: This present study provides the exact prevalence of EML4-ALK rearrangement in different variants for NSCLC patients with ALK positive.

[Investigation on the Possibility of EGFR Mutation Testing on DNA Extracted from Fixation Liquid of Lung Cancer Biopsy]

BACKGROUND

Epidermal growth factor receptor (EGFR) mutation is the most common gene mutation in patients with non-small cell lung cancer (NSCLC). Many international guidelines are recommended to detected the EGFR mutation before the treatment of advanced non-small cell lung cancer. To investigate the possibility of EGFR mutation testing on DNA extracted from fixation liquid of lung cancer biopsy.

METHODS

Fixation liquid of lung cancer biopsy was collected and stored at -80 oC after centrifugal. DNA was extracted and EGFR gene mutation was detected by ARMS. Compared with EGFR mutation status of paraffin-embedded tissues, the consistency, the sensitivity and specificity of EGFR mutation testing were analyzed.

RESULTS

Among the 28 cases of EGFR mutation positive and 20 cases of EGFR mutation negative previously tested on paraffin-embedded tissue by clinic test, 20 cases with EGFR mutation positive and 20 cases with negative were detected by matched fixation liquid of lung cancer biopsy, respectively. The sensitivity and specificity were 71.4% and 100%. Moreover, 52 paraffin-embedded tissues and matched fixation liquid of lung cancer biopsy with unknown EGFR mutation status were detected, and the EGFR mutation positive rate were 36.5% and 28.8% respectively. The sensitivity and specificity of fixation liquid of lung cancer biopsy were 78.9% and 100.0%.

CONCLUSIONS

Extracting the DNA from fixation liquid of lung cancer biopsy may be a kind of feasible way to detect EGFR mutation.

An autopsy case of anaplastic lymphoma kinase-positive lung cancer exacerbated in a short period of time: a case report

Background

Anaplastic lymphoma kinase-positive lung cancer is a form of lung cancer that accounts for approximately 5% of non-small cell lung cancers. Recently, anaplastic lymphoma kinase inhibitors have been used for treatment of anaplastic lymphoma kinase-positive lung cancer, and their high clinical effect has also been demonstrated in cases of advanced stage lung cancer. Alectinib is an anaplastic lymphoma kinase inhibitor that it is recognized as a standard drug for primary therapy because of its superiority to crizotinib.

Case presentation

A 37-year-old Japanese man was admitted to our hospital due to multiple brain metastases. An autopsy report revealed that the cause of death was anaplastic lymphoma kinase-positive lung cancer, exacerbated in a short period despite treatment with alectinib. Necropsy revealed anaplastic lymphoma kinase-positive adenosquamous carcinoma of the lung, suggesting that it was involved in the prognosis of this patient. Based on the autopsy results, we reviewed the pathological tissue from transbronchial lung biopsy at the time of clinical diagnosis. The tissue specimen for clinical diagnosis in this case was a papillary adenocarcinoma. However, when this tissue was immunostained, thyroid transcription factor 1-negative and cytokeratin 5/6-positive parts were recognized. This result indicates that we could diagnose this patient as having had adenosquamous carcinoma of the lung.

Conclusion

In cases of anaplastic lymphoma kinase-positive lung cancer poorly responsive to anaplastic lymphoma kinase inhibitors, re-examination of the tissue should be considered because there is a possibility of anaplastic lymphoma kinase-positive adenosquamous carcinoma.

Comprehensive genomic and immunological characterization of Chinese non-small cell lung cancer patients

Deep understanding of the genomic and immunological differences between Chinese and Western lung cancer patients is of great importance for target therapy selection and development for Chinese patients. Here we report an extensive molecular and immune profiling study of 245 Chinese patients with non-small cell lung cancer. Tumor-infiltrating lymphocyte estimated using immune cell signatures is found to be significantly higher in adenocarcinoma (ADC, 72.5%) compared with squamous cell carcinoma (SQCC, 54.4%). The correlation of genomic alterations with immune signatures reveals that low immune infiltration was associated with EGFR mutations in ADC samples, PI3K and/or WNT pathway activation in SQCC. While KRAS mutations are found to be significantly associated with T cell infiltration in ADC samples. The SQCC patients with high antigen presentation machinery and cytotoxic T cell signature scores are found to have a prolonged overall survival time.

Lung cancer family history and exposure to occupational/domestic coal combustion contribute to variations in clinicopathologic features and gene fusion patterns in non-small cell lung cancer

BACKGROUND

Both genetic and environmental factors contribute to the development of cancer and its mutant spectrum. Lung cancer has familial aggregation. Lung cancer caused by non-tobacco factors has unique pathological and molecular characteristics. The interaction between genetic lung cancer susceptibility and carcinogens from coal burning remains complex and understudied.

METHODS

We selected 410 non-small cell lung cancer (NSCLC) patients with a family history of lung cancer (FLC) and exposure to coal combustion between 2014 and 2017. Clinicopathologic parameters were analyzed. Reverse transcription-PCR was performed to detect ALK, ROS1, RET, and NTRK1 rearrangement.

RESULTS

Among the 410 NSCLC patients, 192 had FLC and 204 (49.8%) were exposed to occupational or domestic coal combustion. FLC patients had the same characteristics regardless of gender and coal exposure: younger age, high female ratio, adenocarcinoma, increased metastasis, later stage at diagnosis, and higher frequency of gene fusion. Sixty-seven patients (16.3%) had gene rearrangement: 51 (12.4%) harbored EML4-ALK fusions and 16 ROS1 fusions (3.9%). The highest gene fusion rate (35.1%, 33/94) occurred in patients with both FLC and high tobacco and coal exposure. ALK fusions and total gene rearrangement were closely associated with women, never smokers, younger age, FLC, and coal exposure.

CONCLUSION

FLC and exposure to coal combustion have an important impact on the clinicopathological characteristics and gene fusion mode of NSCLC, particularly in cases of higher levels of carcinogens, and genetic susceptibility has a greater impact. Our findings may help evaluate the effect of FLC and coal exposure on the pathogenesis of lung cancer.

Prognostic value of KRAS/TP53/PIK3CA in non-small cell lung cancer

The present study explored the association between KRAS proto-oncogene GTPase (KRAS), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA) and tumor protein p53 (TP53) mutations, and the clinical features and survival prognosis in 50 patients with non-small cell lung cancer (NSCLC). The most common concurrent single gene mutation was TP53, followed by KRAS and PIK3CA. Co-existing mutations were found in 17 patients. KRAS, PIK3CA and TP53 mutations were associated with carbohydrate antigen 19-9 expression, invasive growth, vacuolar signs and margin lobulation on chest CT. The incidence of distant metastasis (bone and adrenal) with KRAS and TP53 mutations was greater than that of local metastasis (pleura). Patients with the wild-type genes experienced longer progression-free survival (PFS) times than those with KRAS, TP53, KRAS/TP53 or PIK3CA/TP53 mutations. Patients with KRAS/TP53 or PIK3CA/TP53 mutations experienced shorter PFS times than those with a single KRAS or TP53 mutation. KRAS, PIK3CA and TP53 mutations were associated with distant metastases and a poor prognosis. Patients with NSCLC should receive routine KRAS, PIK3CA and TP53 gene sequencing to determine mutations for the analysis of clinical characteristics and prognosis.

Anaplastic lymphoma kinase fusions: Roles in cancer and therapeutic perspectives

Receptor tyrosine kinase (RTK) anaplastic lymphoma kinase (ALK) serves a crucial role in brain development. ALK is located on the short arm of chromosome 2 (2p23) and exchange of chromosomal segments with other genes, including nucleophosmin (NPM), echinoderm microtubule-associated protein-like 4 (EML4) and Trk-fused gene (TFG), readily occurs. Such chromosomal translocation results in the formation of chimeric X-ALK fusion oncoproteins, which possess potential oncogenic functions due to constitutive activation of ALK kinase. These proteins contribute to the pathogenesis of various hematological malignancies and solid tumors, including lymphoma, lung cancer, inflammatory myofibroblastic tumors (IMTs), Spitz tumors, renal carcinoma, thyroid cancer, digestive tract cancer, breast cancer, leukemia and ovarian carcinoma. Targeting of ALK fusion oncoproteins exclusively, or in combination with ALK kinase inhibitors including crizotinib, is the most common therapeutic strategy. As is often the case for small-molecule tyrosine kinase inhibitors (TKIs), drug resistance eventually develops via an adaptive secondary mutation in the ALK fusion oncogene, or through engagement of alternative signaling mechanisms. The updated mechanisms of a variety of ALK fusions in tumorigenesis, proliferation and metastasis, in addition to targeted therapies are discussed below.

Epidermal Growth Factor Receptor (EGFR) Mutations and Anaplastic Lymphoma Kinase/Oncogene or C-Ros Oncogene 1 (ALK/ROS1) Fusions Inflict Non-Small Cell Lung Cancer (NSCLC) Female Patients Older Than 60 Years of Age

Background

Lung cancer has become a leading disease for the tumor-induced mortality. Non-small cell lung cancer (NSCLC) accounts for approximately 80% of all lung cancers. The present research aimed to evaluate the correlation between the anaplastic lymphoma kinase/oncogene or c-ros oncogene 1 (ALK/ROS1) fusions or mutations of epidermal growth factor receptor (EGFR) and ages or gender of patients.

Material/Methods

Among 1449 NSCLC patients, 457 patients who were diagnosed as consecutive EGFR mutations or ALK/ROS1 fusions between November 2016 and February 2018 were involved in the present study. EGFR genes or ALK/ROS1 mutations were detected by using DNA sequencing technique and amplification-refractory mutation system (ARMS). The mRNAs of ROS1 and ALK fusion were examined by using polymerase chain reaction technique and fusion gene detection kit.

Results

Females were more often inflicted by the EGFR mutations, especially for the exon 19 deletion and L858R mutation. There were significantly more ALK/ROS1 fusions in females compared to males (P<0.05) and significantly more ALK/ROS1 fusions in <60 years of age patients compared to patients older than 60 years of age (P<0.05). Exon 21 L858R and L861Q dominantly occurred in patients ≥60 years of age and exon 19 deletion in patients <60 years of age. EML-ALK-1 mainly existed in the female NSCLC patients.

Conclusions

EGFR mutations and ALK/ROS1 fusions mainly occurred in the NSCLC female patients who were older than 60 years of age.

A genomic and clinicopathological study of non-small-cell lung cancers with discordant ROS1 gene status by fluorescence in-situ hybridisation and immunohistochemical analysis

AIMS

ROS1 immunohistochemistry (IHC) using D4D6 antibody is a useful tool for screening patients with non-small-cell lung cancer (NSCLC) who may be suitable for targeted therapy. Many studies and our data have identified cases that express the ROS1 protein strongly but are negative for ROS1 by fluorescence in-situ hybridisation (FISH). The present study investigated the driver mutation and clinicopathological characteristics of 26 discordant cases (ROS1 IHC-positive but FISH-negative) to find new clues for distinguishing real ROS1-rearranged cases.

METHODS AND RESULTS

Tumours from 26 discordant cases were analysed for clinicopathological characteristics, mutations in EGFR, KRAS, ERBB2, BRAF and PIK3CA; fusions in ALK and RET; and amplifications in MET, ERBB2 and ROS1. ROS1-rearranged NSCLCs were significantly more likely to be found in younger patients and at an advanced stage; they showed cribriform features, extracellular mucus and psammoma bodies, whereas ROS1-discordant cases were found in older patients at a relatively early tumour-node-metastasis (TNM) stage and showed a lepidic growth pattern (all P < 0.001). Most ROS1-rearranged NSCLCs had no concurrent mutation, whereas 73% of discordant cases harboured genetic aberrations, including EGFR and ERBB2. Compared with general lung adenocarcinomas, ERBB-2 abnormality was disproportionately high in ROS1-discordant cases. Moreover, we optimised the scoring criteria for ROS1 IHC as 'H score > 150 and no concurrent mutations'; the specificity was then increased to 81.6%.

CONCLUSIONS

Compared with ROS1-rearranged cases, ROS1-discordant patients showed distinct clinical and morphological features and often harboured another oncogenic driver alteration. The use of optimised screening criteria will increase the specificity of ROS1 antibody.

Clinically significant sub-clonality for common drivers can be detected in 26% of KRAS/EGFR mutated lung adenocarcinomas

Genetic sub-clonality has been described in multiple malignancies, however the presence of sub-clonality for major drivers in lung adenocarcinoma and its clinical significance is a subject under debate. Using molecular and morphometric approach, 347 lung adenocarcinoma samples were analyzed for KRAS and EGFR sub-clonality, which was further correlated with clinical and pathological variables.KRAS and EGFR mutations were identified in 100 (29%) and 82 (23%) cases, respectively. One hundred and forty four KRAS or EGFR positive cases were also available for morphometric analysis, among which 37 (26%) were defined as sub-clonal. The presence of sub-clonality was associated with shorter survival time (p=0.02). Interestingly, cases with sub-clonality were also associated with earlier disease stage (89% vs 66% stage I disease in sub-clonal vs clonal cases, respectively, p=0.01) and less lymph node involvement (8% vs 25% in sub-clonal vs clonal cases, respectively, p=0.02). Our findings demonstrate the presence of sub-clonality for mutations in common drivers in lung adenocarcinoma and link it both to earlier disease stage and to poor survival. These findings are in line with the different evolutionary models that can present with genetic sub-clonality.

[Prognostic Analysis of Patients with Advanced Non-small Cell Lung Cancer in Different Genotypes]

BACKGROUND

Non-small cell lung cancer (NSCLC) has been transformed from the treatment according to histological type to genotype treatment model. The epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) genes are the most important drivers in lung cancer. The aim of this study is to explore the clinical characteristics and prognostic factors of patients with advanced NSCLC with different genotypes.

METHODS

We retrospectively reviewed the clinical data of 553 advanced NSCLC patients with EGFR mutations and ALK positive who were hospitalized in the Beijing Chest Hospital from July 2004 to December 2015, and the independent prognostic factors of patients were analyzed by Cox proportional hazards regression model.

RESULTS

The clinical data of 553 patients (227 with EGFR mutations, 58 with ALK positive, 2 with EGFR and ALK co-mutation and 266 with wild-type) with advanced NSCLC were enrolled in this study. The median survival time of 227 patients with EGFR mutations was 28.7 mo (95%CI: 22.160-35.240), and the performance status (PS) score (0-1) (HR=4.451; 95%CI: 2.112-9.382; P<0.001) and EGFR-tyrosine kinase inhibitors (TKIs) targeted therapy (HR=2.785; 95%CI: 1.871-4.145; P<0.001) were the independent prognostic factors for the survival of patients harboring EGFR mutations. The median survival time of 58 patients with ALK positive was 15.5 mo (95%CI: 10.991-20.009), and treatment with crizotinib (P=0.022) was the independent influence factor for the survival of ALK positive patients. The median survival time of 266 patients with wild-type was 12.1 mo (95%CI: 10.660-13.540), and the PS score (0-1) (HR=2.313; 95%CI: 1.380-3.877; P=0.001) and treatment with chemotherapy (HR=1.911; 95%CI: 1.396-2.616; P<0.001) were the independent prognostic factors for the survival of wild-type patients CONCLUSIONS: The prognosis of patients with advanced NSCLC is associated with genetic mutation, and targeted therapy has a improvement on survival for patients with EGFR mutations or ALK rearrangement.

Clinicopathologic characteristics of EGFR, KRAS, and ALK alterations in 6,595 lung cancers

BACKGROUND

EGFR, KRAS, and ALK alterations are major genetic changes found in non-small cell lung cancers (NSCLCs). Testing advanced lung adenocarcinoma tumors for these three genes is now standard care. The purpose of this study was to investigate the clinicopathologic expression pattern of these three genes in East Asian NSCLC patients.

PATIENTS AND METHODS

We conducted a retrospective study of all patients tested for mutations of these three genes at a single institute in Korea between 2006 and 2014. Study data were extracted from electronic medical records. Univariate and multivariate logistic regression analyses were used to measure associations between clinicopathologic features and alterations of EGFR, KRAS, and ALK.

RESULTS

We detected 12 EGFR-mutated tumors with additional mutations in KRAS (N=6, 0.1%) or ALK (N=6, 0.1%). General clinicopathologic characteristics of tumors with EGFR, KRAS, or ALK mutations were similar to previous reports. Patients having EGFR L858R point mutations were older than patients having EGFR exon 19 deletions. EGFR G719X point mutations were more common in men and smokers than exon 19 deletions or L858R point mutations. Tumors having KRAS G12C mutations were less often of mucinous type than those with G12D or G12V, mutations.

CONCLUSIONS

This is the largest three gene molecular epidemiology study in East Asian NSCLC patients. Each genetic alteration was associated with distinct clinicopathologic characteristics. Furthermore, different age and sex are associated with different subtypes of EGFR and KRAS mutations.

Comprehensive profiling and quantitation of oncogenic mutations in non small-cell lung carcinoma using single molecule amplification and re-sequencing technology

Activating and resistance mutations in the tyrosine kinase domain of several oncogenes are frequently associated with non-small cell lung carcinoma (NSCLC). In this study we assessed the frequency, type and abundance of EGFR, KRAS, BRAF, TP53 and ALK mutations in tumour specimens from 184 patients with early and late stage disease using single molecule amplification and re-sequencing technology (SMART). Based on modelling of EGFR mutations, the detection sensitivity of the SMART assay was at least 0.1%. Benchmarking EGFR mutation detection against the gold standard ARMS-PCR assay, SMART assay had a sensitivity and specificity of 98.7% and 99.0%. Amongst the 184 samples, EGFR mutations were the most prevalent (59.9%), followed by KRAS (16.9%), TP53 (12.7%), EML4-ALK fusions (6.3%) and BRAF (4.2%) mutations. The abundance and types of mutations in tumour specimens were extremely heterogeneous, involving either monoclonal (51.6%) or polyclonal (12.6%) mutation events. At the clinical level, although the spectrum of tumour mutation(s) was unique to each patient, the overall patterns in early or advanced stage disease were relatively similar. Based on these findings, we propose that personalized profiling and quantitation of clinically significant oncogenic mutations will allow better classification of patients according to tumour characteristics and provide clinicians with important ancillary information for treatment decision-making.

Relationship between driver gene mutations, their relative protein expressions and survival in non-small cell lung carcinoma in Macao

OBJECTIVES

We report the status of most common gene mutations in non-small cell lung carcinoma (NSCLC) in Macao, and explore the relationship between each gene mutation and clinicopathologic features and survival.

METHODS

EGFR, KRAS and BRAF mutations were detected by PCR in 122 cases of NSCLC. ALK translocation and MET amplification were detected by fluorescence in situ hybridization (FISH). MET and thyroid transcription factor (TTF-1) were investigated by immunohistochemistry. Clinical data were collected for analyzing their correlation with the gene mutations.

RESULTS

The mutation of EGFR, KRAS and BRAF was detected in 48 (39.3%), 13 (10.7%) and 3 (2.5%) of 122 cases of NSCLC, respectively. ALK translocation and MET amplification were detected in 7 (5.7%) and 3 cases (2.5%). The rate of EGFR mutation was significantly higher in female and non-smoker patients. In TTF-1 positive cases EGFR mutation was more frequent. Age of the patients over 62-year old was correlated with KRAS mutations. The concordance between ALK IHC and FISH was 58.3%. The MET protein in the cases with MET amplification was 100% positive. The survival was lower in the patients with positive MET protein than those with negative. MET protein was an independent prognostic factor for NSCLC.

CONCLUSIONS

EGFR mutation occurred frequently in the female never smoke patients with NSCLC. KRAS mutation was more common in old patients. Negative MET protein expression could be used as a negative predictive marker of MET amplification. MET protein expression was an independent prognostic factor for NSCLC.

Mortality outcomes of low-dose computed tomography screening for lung cancer in urban China: a decision analysis and implications for practice

BACKGROUND

Mortality outcomes in trials of low-dose computed tomography (CT) screening for lung cancer are inconsistent. This study aimed to evaluate whether CT screening in urban areas of China could reduce lung cancer mortality and to investigate the factors that associate with the screening effect.

METHODS

A decision tree model with three scenarios (low-dose CT screening, chest X-ray screening, and no screening) was developed to compare screening results in a simulated Chinese urban cohort (100,000 smokers aged 45-80 years). Data of participant characteristics were obtained from national registries and epidemiological surveys for estimating lung cancer prevalence. The selection of other tree variables such as sensitivities and specificities of low-dose CT and chest X-ray screening were based on literature research. Differences in lung cancer mortality (primary outcome), false diagnoses, and deaths due to false diagnosis were calculated. Sensitivity analyses were performed to identify the factors that associate with the screening results and to ascertain worst and optimal screening effects considering possible ranges of the variables.

RESULTS

Among the 100,000 subjects, there were 448, 541, and 591 lung cancer deaths in the low-dose CT, chest X-ray, and no screening scenarios, respectively (17.2% reduction in low-dose CT screening over chest X-ray screening and 24.2% over no screening). The costs of the two screening scenarios were 9387 and 2497 false diagnoses and 7 and 2 deaths due to false diagnosis among the 100,000 persons, respectively. The factors that most influenced death reduction with low-dose CT screening over no screening were lung cancer prevalence in the screened cohort, low-dose CT sensitivity, and proportion of early-stage cancers among low-dose CT detected lung cancers. Considering all possibilities, reduction in deaths (relative numbers) with low-dose CT screening in the worst and optimal cases were 16 (5.4%) and 288 (40.2%) over no screening, respectively.

CONCLUSIONS

In terms of mortality outcomes, our findings favor conducting low-dose CT screening in urban China. However, approaches to reducing false diagnoses and optimizing important screening conditions such as enrollment criteria for screening are highly needed.

An Immunohistochemical Study of Anaplastic Lymphoma Kinase and Epidermal Growth Factor Receptor Mutation in Non-Small Cell Lung Carcinoma

INTRODUCTION

Lung cancer is one of the leading causes of cancer related death. Targeted treatment for specific markers may help in reducing the cancer related morbidity and mortality.

AIM

To study expression of Anaplastic Lymphoma Kinase (ALK)and Epidermal Growth Factor Receptor (EGFR) mutations in patients of Non-Small Cell Lung Cancer NSCLC, that are the targets for specific ALK inhibitors and EGFR tyrosine kinase inhibitors.

MATERIALS AND METHODS

Total 69 cases of histologically diagnosed NSCLC were examined retrospectively for immunohistochemical expression of EGFR and ALK, along with positive control of normal placental tissue and anaplastic large cell lymphoma respectively.

RESULTS

Of the NSCLC, Squamous Cell Carcinoma (SCC) accounted for 71.0% and adenocarcinoma was 26.1%. ALK expression was seen in single case of 60-year-old female, non-smoker with adenocarcinoma histology. EGFR expression was seen in both SCC (59.18%) and adenocarcinoma in (77.78%) accounting for 63.77% of all cases. Both ALK and EGFR mutation were mutually exclusive.

CONCLUSION

EGFR expression was seen in 63.77% of cases, highlighting the importance of its use in routine analysis, for targeted therapy and better treatment results. Although, ALK expression was seen in 1.45% of all cases, it is an important biomarker in targeted cancer therapy. Also, the mutually exclusive expression of these two markers need further studies to develop a diagnostic algorithm for NSCLC patients.

Clinical Significance and Next-Generation Sequencing of Chinese Pulmonary Sarcomatoid Carcinoma

Pulmonary Sarcomatoid Carcinoma (PSC) constitutes a heterogeneous group of non-small-cell lung carcinomas (NSCLCs) with a poor prognosis. In this study, a group of 7 patients with PSC was studied. Microscope analysis of all 7 cases revealed a pleomorphic carcinoma subtype. Moreover, 5 cases (71.4%) were composed entirely of malignant sarcomatoid-like elements, and 2 cases (28.6%) were composed of malignant sarcomatoid-like elements and at least 10% adenocarcinoma-like elements. Immunohistochemically, the PSC components of all 7 cases were positive for vimentin and cytokeratins, including cytokeratin (CK) and cytokeratin 7 (CK7). Next-Generation Sequencing (NGS) was performed, and a total of 136 putative somatic variants and one gene fusion were identified, of which 16 variants were considered hot spot mutations, including the genes EGFR, EML4-ALK, MET, BRAF, PIK3CA, and TP53. Of these hot spot mutations, one sample expressing an EML4-ALK fusion was further confirmed by Ventana IHC, and one sample containing an EGFR exon 19 deletion was also confirmed. The NGS results imply that TP53 mutations occur often in PSCs and that EML4-ALK fusion events and EGFR exon deletions also occur in these rare tumors. Molecular targeted therapy may be a useful treatment strategy for these rare lung tumors.

Mutant KRAS promotes malignant pleural effusion formation

Malignant pleural effusion (MPE) is the lethal consequence of various human cancers metastatic to the pleural cavity. However, the mechanisms responsible for the development of MPE are still obscure. Here we show that mutant KRAS is important for MPE induction in mice. Pleural disseminated, mutant KRAS bearing tumour cells upregulate and systemically release chemokine ligand 2 (CCL2) into the bloodstream to mobilize myeloid cells from the host bone marrow to the pleural space via the spleen. These cells promote MPE formation, as indicated by splenectomy and splenocyte restoration experiments. In addition, KRAS mutations are frequently detected in human MPE and cell lines isolated thereof, but are often lost during automated analyses, as indicated by manual versus automated examination of Sanger sequencing traces. Finally, the novel KRAS inhibitor deltarasin and a monoclonal antibody directed against CCL2 are equally effective against an experimental mouse model of MPE, a result that holds promise for future efficient therapies against the human condition.

ALK rearrangement in specific subtypes of lung adenocarcinoma: immunophenotypic and morphological features

Lung adenocarcinomas are characterized by a variety of genetic and epigenetic changes that lead to activation of specific signaling pathways. This allowed the classification of lung adenocarcinomas according to genetic alterations and the clinical development of novel anticancer agents that affect the activity of specific oncoproteins. In such a context, chromosomal rearrangements that cause constitutive activation of ALK gene define a category of lung adenocarcinomas that is amenable to targeted therapy with ALK inhibitors. Thus, a major issue of current research is to define the morphological and immunophenotypic features of lung ALK-rearranged adenocarcinomas to improve the selection of tumors suitable for molecular genotyping. ALK status was determined, by immunohistochemistry and fluorescence in situ hybridization, in 94 surgically resected lung adenocarcinomas and correlated with histomorphological parameters. Indeed, ALK rearrangement was observed in 10/94 (11%) lung adenocarcinomas and enriched in tumors with a predominant mucinous (46%; p < 0.05) and solid (29%; p < 0.05) pattern. By contrast, it was lacking or sporadically observed in lung adenocarcinomas with predominant acinar, papillary or lepidic pattern. Moreover, the presence of signet-ring cells was predominantly observed in ALK-rearranged tumors (47%; p < 0.05). These data suggest that ALK rearrangement is associated with specific and distinct clinical-pathological characters compared to other genotypes. Thus, the knowledge of these characteristics can improve the diagnostic accuracy and lead to a better understanding of the behavior of ALK-rearranged NSCLC.

Clinicopathological Features and Therapeutic Responses of Chinese Patients with Advanced Lung Adenocarcinoma Harboring an Anaplastic Lymphoma Kinase Rearrangement

BACKGROUND

Presence of anaplastic lymphoma kinase (ALK) rearrangement is an indication for crizotinib in the treatment of patients with advanced or metastatic lung adenocarcinoma. Here, we sought to elucidate the association between clinicopathological features and ALK rearrangement status in Chinese patients with advanced lung adenocarcinoma harboring an ALK rearrangement.

PATIENTS AND METHODS

ALK rearrangement status was determined using immunohistochemistry (IHC) in tumor tissues from 120 patients with advanced lung adenocarcinoma, and further assessed by fluorescence in situ hybridization (FISH) assay. The associations between ALK rearrangement status and clinicopathological features were analyzed.

RESULTS

According to IHC testing, the ALK-positive rate among the advanced lung adenocarcinoma patients was 6.67% (8/120). FISH validation found 5 patients with ALK rearrangement among the 8 IHC-positive cases. No significant difference was observed regarding age, sex, or smoking status between FISH-positive and -negative patients (p > 0.05). None of the 5 FISH-positive patients benefited from first-line chemotherapy.

CONCLUSION

IHC can be used as a reliable method for ALK rearrangement screening in patients with lung adenocarcinoma, but further FISH validation is imperative. Presence of ALK rearrangement predicts a more aggressive biological behavior of the tumor and might be indicative of poor response to chemotherapy.

Targeting stemness is an effective strategy to control EML4-ALK+ non-small cell lung cancer cells

The fusion between anaplastic lymphoma kinase (ALK) and echinoderm microtubule-associated protein-like 4 (EML4) is a causative factor in a unique subset of patients with non-small cell lung carcinoma (NSCLC). Although the inhibitor crizotinib, as it blocks the kinase activity of the resulting EML4-ALK fusion protein, displays remarkable initial responses, a fraction of NSCLC cases eventually become resistant to crizotinib by acquiring mutations in the ALK domain or activating bypass pathways via EGFR, KIT, or KRAS. Cancer stem cell (CSC) theory provides a plausible explanation for acquisition of tumorigenesis and resistance. However, the question as to whether EML4-ALK-driven tumorigenesis is linked with the stem-like property and whether the stemness is an effective target in controlling EML4-ALK+ NSCLC including crizotinib-resistant NSCLC cells has not been addressed. Here, we report that stem-like properties stem from ALK activity in EML4-ALK+ NSCLC cells. Notably, treatment with rapamycin, a CSC targeting agent, attenuates stem-like phenotypes of the EML4-ALK+ cells, which increased capability of tumor formation and higher expression of stemness-associated molecules such as ALDH, NANOG, and OCT4. Importantly, combinational treatment with rapamycin and crizotinib leads to synergistic anti-tumor effects on EML4-ALK+ NSCLC cells as well as on those resistant to crizotinib. Thus, we provide a proof of principle that targeting stemness would be a novel strategy to control intractable EML4-ALK+ NSCLC.

[Methylation Status of the SOCS3 Gene Promoter in H2228 Cells and EML4-ALK-positive Lung Cancer Tissues]

BACKGROUND

The EML4-ALK fusion gene is a newly discovered driver gene of non-small cell lung cancer and exhibits special clinical and pathological features. The JAK-STAT signaling pathway, an important downstream signaling pathway of EML4-ALK, is aberrantly sustained and activated in EML4-ALK-positive lung cancer cells fusion gene, but the underlying reason remains unknown. The suppressor of cytokine signaling (SOCS) is a negative regulatory factor that mainly inhibits the proliferation, differentiation, and induction of apoptotic cells by inhibiting the JAK-STAT signaling pathway. The aberrant methylation of the SOCS gene leads to inactivation of tumors and abnormal activation of the JAK2-STAT signaling pathway. The aim of this study is to investigate the methylation status of the SOCS3 promoter in EML4-ALK-positive H2228 cells and lung cancer tissues.

METHODS

The methylation status of the SOCS3 promoter in EML4-ALK-positive H2228 lung cancer cells and lung cancer tissues was detected by methylation-specific PCR (MSP) analysis and verified by DNA sequencing. The expression levels of SOCS3 in H2228 cells were detected by Western blot and Real-time PCR analyses after treatment with the DNA methyltransferase inhibitor 5'-Aza-dC.

RESULTS

MSP and DNA sequencing assay results indicated the presence of SOCS3 promoter methylation in H2228 cells as well as in three cases of seven EML4-ALK-positive lung cancer tissues. The expression level of SOCS3 significantly increased in H2228 cells after 5'-Aza-dC treatment.

CONCLUSIONS

The aerrant methylation of the SOCS3 promoter region in EML4-ALK (+) H2228 cells and lung cancer tissues may be significantly involved in the pathogenesis of EML4-ALK-positive lung cancer.

Intergenically Spliced Chimeric RNAs in Cancer

Gene fusions and their encoded products (fusion RNAs and proteins) are viewed as one of the hallmarks of cancer. Traditionally, they were thought to be generated solely by chromosomal rearrangements. However, recent discoveries of trans-splicing and cis-splicing events between neighboring genes, suggest that there are other mechanisms to generate chimeric fusion RNAs without corresponding changes in DNA. In addition, chimeric RNAs have been detected in normal physiology, complicating the use of fusions in cancer detection and therapy. On the other hand, "intergenically spliced" fusion RNAs represent a new repertoire of biomarkers and therapeutic targets. Here, we review current knowledge on chimeric RNAs and implications for cancer detection and treatment, and discuss outstanding questions for the advancement of the field.

Comparison of bevacizumab plus chemotherapy with chemotherapy alone in advanced non-small-lung cancer patients

Bevacizumab plus chemotherapy was approved by the US Food and Drug Administration (FDA) as a first-line treatment for advanced nonsquamous, non-small-cell lung cancer (NSCLC) in 2006. This study retrospectively compared the efficacy of bevacizumab plus chemotherapy with chemotherapy alone as the first-line and second-line treatment as well as the maintenance treatment for advanced NSCLC patients. A total of 1,352 patients were included and we analyzed the efficacy evaluation according to the criteria of the Response Evaluation Criteria In Solid Tumors (RECIST), survival, and adverse reactions. The data showed that for bevacizumab plus chemotherapy as the first-line treatment, the median progression-free survival (mPFS) and median overall survival (mOS) were 11.5 and 17.0 months, respectively, compared to 7.0 and 14 months, respectively, in patients who received chemotherapy alone (P<0.01). With bevacizumab plus chemotherapy as maintenance treatment, the mPFS and mOS were 6.0 and 17.4 months, respectively, compared to 3.0 and 15.0 months, respectively, with chemotherapy alone (P<0.01). With bevacizumab plus chemotherapy as the second-line treatment, the mPFS was 3.0 months compared to only 2.0 months with chemotherapy alone (P<0.01). The overall responses to the different regimens showed that the remission rate with bevacizumab plus chemotherapy was higher than that with chemotherapy alone (31.8% vs 25.5%, P<0.05), although there was no statistical difference in the disease control rate with either first- or second-line treatment. In conclusion, chemotherapy plus bevacizumab as the first-line and maintenance treatment, led to better curative rates and tolerable adverse reactions compared with chemotherapy alone in advanced NSCLC patients. Bevacizumab combined with cytotoxic drugs was suitable as the second-line treatment for such patients.

Lung cancer with concurrent EGFR mutation and ROS1 rearrangement: a case report and review of the literature

ROS1 rearrangement has recently emerged as a new molecular subtype in non-small cell lung cancer, and is predominantly found in lung adenocarcinomas compared with other oncogenes such as EGFR, KRAS, or ALK. Patients who have both mutations are extremely rare. Here we report a 50-year-old female diagnosed with adenocarcinoma with sarcomatoid differentiation, who was shown to have EGFR and ROS1 mutations. The patient was treated surgically and received three cycles of adjuvant postoperative chemotherapy. In addition, we reviewed the previously reported cases and related literature. This presentation will provide further understanding of the underlying molecular biology and optimal treatment for non-small cell lung cancer patients with more than one driver mutation.

ALK-rearranged pulmonary adenocarcinoma in Thai Patients: From diagnosis to treatment efficacy

Background

Anaplastic lymphoma kinase (ALK) gene rearrangement is detected in 3 % to 13 % of non-small cell lung carcinoma patients, and these patients benefit from ALK inhibitors. The aim of this study was to determine the prevalence, the clinical and histological characteristics and the treatment outcomes of ALK-rearranged lung adenocarcinoma using immunohistochemistry (IHC) IHC, reverse transcription polymerase chain reaction (RT-PCR) and fluorescence in situ hybridization (FISH) methodologies.

Methods

A total of 268 pulmonary adenocarcinoma patients were screened for ALK expression by ALK IHC, which was confirmed by FISH and/or RT-PCR for ALK gene rearrangement. The treatment outcomes of ALK-rearranged patients were retrospectively reviewed.

Results

ALK gene rearrangement was identified in 26 cases (9.7 %) with no EGFR co-mutation, and it showed significant associations with younger age, female sex and non-smoker status (p < 0.05). A cribriform growth pattern was identified as the dominant histologic feature, and a solid signet ring cell component was focally present in a minority of the cases. Among 12 ALK-rearranged patients with conventional treatment, seven cases in the early stage of disease were cured and alive, and five patients in the late stage of the disease progressed and died, with a median overall survival (OS) at 14 months. Of the 14 patients receiving crizotinib, all of them had clinical benefit from crizotinib treatment, with one patient having a complete response (CR), 12 patients having a partial response (PR) and one patient having stable disease (SD). On the cutoff date, six of 14 patients were continuing crizotinib treatment with a median time of response of 7.5 (3–13) months, while eight patients had disease progression, and five of them died with a median OS at 8 months.

Conclusion

ALK gene rearrangement tended to occur in younger, non-smoking, female patients. ALK IHC is a reliable screening method to detect ALK gene rearrangement. Crizotinib therapy provided treatment benefit in ALK-rearranged adenocarcinoma patients especially in advanced stages of the disease.

Serum carcinoembryonic antigen levels before initial treatment are associated with EGFR mutations and EML4- ALK fusion gene in lung adenocarcinoma patients

BACKGROUND

Epidermal growth factor receptor (EGFR) mutations and echinoderm microtubule associated protein like 4-anaplastic lymphoma kinase (EML4-ALK) define specific molecular subsets of lung adenocarcinomas with distinct clinical features. Our purpose was to analyze clinical features and prognostic value of EGFR gene mutations and the EML4-ALK fusion gene in lung adenocarcinoma.

PATIENTS AND METHODS

EGFR gene mutations and the EML4-ALK fusion gene were detected in 92 lung adenocarcinoma patients in China. Tumor marker levels before first treatment were measured by electrochemiluminescence immunoassay.

RESULTS

EGFR mutations were found in 40.2% (37/92) of lung adenocarcinoma patients, being identified at high frequencies in never-smokers (48.3% vs. 26.5% in smokers; P=0.040) and in patients with abnormal serum carcinoembryonic antigen (CEA) levels before the initial treatment (58.3% vs. 28.6%, P=0.004). Multivariate analysis revealed that a higher serum CEA level before the initial treatment was independently associated with EGFR gene mutations (95%CI: 1.476~11.343, P=0.007). We also identified 8 patients who harbored the EML4-ALK fusion gene (8.7%, 8/92). In concordance with previous reports, younger age was a clinical feature for these (P=0.008). Seven of the positive cases were never smokers, and no coexistence with EGFR mutation was discovered. In addition, the frequency of the EML4-ALK fusion gene among patients with a serum CEA concentration below 5 ng/ml seemed to be higher than patients with a concentration over 5 ng/ml (P=0.021). No significant difference was observed for time to progression and overall survival between EML4-ALK-positive group and EML4-ALK-negative group or between patients with and without an EGFR mutation.

CONCLUSIONS

The serum CEA level before the initial treatment may be helpful in screening population for EGFR mutations or EML4-ALK fusion gene presence in lung adenocarcinoma patients.

Molecular mechanisms that underpin EML4-ALK driven cancers and their response to targeted drugs

A fusion between the EML4 (echinoderm microtubule-associated protein-like) and ALK (anaplastic lymphoma kinase) genes was identified in non-small cell lung cancer (NSCLC) in 2007 and there has been rapid progress in applying this knowledge to the benefit of patients. However, we have a poor understanding of EML4 and ALK biology and there are many challenges to devising the optimal strategy for treating EML4-ALK NSCLC patients. In this review, we describe the biology of EML4 and ALK, explain the main features of EML4-ALK fusion proteins and outline the therapies that target EML4-ALK. In particular, we highlight the recent advances in our understanding of the structures of EML proteins, describe the molecular mechanisms of resistance to ALK inhibitors and assess current thinking about combinations of ALK drugs with inhibitors that target other kinases or Hsp90.

Significance and evaluation of anaplastic lymphoma kinase by immunohistochemistry in non-small cell lung cancer

We used immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR) to evaluate anaplastic lymphoma kinase (ALK) protein expression and gene rearrangements, respectively, in 283 cases of wild-type epidermal growth factor receptor (EGFR) non-small cell lung cancer biopsy specimens. Immunohistochemistry was positive for ALK in 52 cases (18.4 %), and there was no significant difference in staining between various monoclonal antibodies (Roche ALK test kit, D5F3, p-ALK, and EML4-ALK). On RT-PCR, 36 cases (12.7 %) were positive for ALK. Immunohistochemistry and RT-PCR were both positive in 35 cases and both negative in 230 cases, and both have a high consistency (265/283, 93.6 %). Including 17 cases, immunohistochemistry was positive but RT-PCR was negative, and in one case, immunohistochemistry was negative but RT-PCR was positive. On fluorescence in situ hybridization (FISH) testing of these 18 cases, only three cases were positive (one RT-PCR was positive; two immunohistochemistry were positive). There is a high prevalence of ALK positivity in wild-type EGFR non-small cell lung cancer. Immunohistochemistry for the detection of ALK gene rearrangements was highly consistent with RT-PCR, and thus, it is a good screening tool but produces false positive results that necessitate further screening by RT-PCR or FISH.

Distinctive Patterns of Initially Presenting Metastases and Clinical Outcomes According to the Histological Subtypes in Stage IV Non-Small Cell Lung Cancer

This study was designed to compare the primary patterns of metastases and clinical outcomes between adenocarcinoma (Adenoca) and squamous cell carcinoma (SQ) in initially diagnosed stage IV non-small cell lung cancer (NSCLC).Between June 2007 and June 2013, a total of 427 eligible patients were analyzed. These patients were histologically confirmed as Adenoca or SQ and underwent systemic imaging studies, including 18F-fluorodeoxyglucose positron emission tomography/computed tomography and brain imaging. Synchronous metastatic sites were categorized into 7 areas, and whole-body metastatic scores were calculated from 1 to 7 by summation of each involved region. We compared the patient, tumor, and metastatic characteristics according to the histological subtypes, and examined clinical outcomes.The enrolled study cohort comprised 81% (n = 346) Adenoca patients and 19% (n = 81) SQ patients. The median age of the study population was 65 years (range, 30-94 years), and 263 (61.6%) patients were male. The most common metastatic sites were thoracic lymph nodes (LNs) (84.3%), followed by lung to lung/lymphangitic spread (59%) and bone (54.8%). The distribution of patient characteristics revealed that age ≥65 years (69.1% vs 50.6%; P = 0.003) and male sex (84% vs 56.4%; P < 0.001) were more frequently found in SQ patients. Regarding metastatic features, bone metastasis (60.4% vs 30.9%; P < 0.001), lung to lung/lymphangitic metastasis (63% vs 42%; P = 0.001), and brain metastasis (35% vs 16%; P = 0.001) were significantly and more frequently found in Adenoca patients. Patients with high metastatic scores (score 3-6) were more frequently found to have Adenoca (91.6% vs 73.4%; P < 0.001). In multivariate prognostic evaluation, sex (P = 0.001), age (P < 0.001), histology (P < 0.001), LN status (P = 0.032), pleural/pericardial metastasis (P = 0.003), abdomen/pelvis metastasis (P < 0.001), axilla/neck metastasis (P = 0.006), and treatment factors (P < 0.001) remained independent prognostic factors affecting overall survival.We observed distinctive patterns of primary metastases and clinical outcomes according to the histological subtypes in stage IV NSCLC. Future studies need to disclose the underlying mechanism of these unique metastatic features and tumor biologies.