ROS1

Gene Summary

Gene:ROS1; ROS proto-oncogene 1, receptor tyrosine kinase
Aliases: ROS, MCF3, c-ros-1
Location:6q22.1
Summary:This proto-oncogene, highly-expressed in a variety of tumor cell lines, belongs to the sevenless subfamily of tyrosine kinase insulin receptor genes. The protein encoded by this gene is a type I integral membrane protein with tyrosine kinase activity. The protein may function as a growth or differentiation factor receptor. [provided by RefSeq, Jul 2008]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:proto-oncogene tyrosine-protein kinase ROS
Source:NCBIAccessed: 16 March, 2017

Ontology:

What does this gene/protein do?
Show (18)

Cancer Overview

In a study of 556 Chinese patients wih non-small cell lung cancer (NSCLC), Rimkunas et al (2012) found 9 (2%) tumors expressed ROS1 and 22 (4%) expressed ALK. They used FISH to identify ALK or ROS1 rearrangements and RTPCR to identify fusion partners: and found fusions of CD74-ROS1, SLC34A2-ROS1, and FIG-ROS1. Davies (2012) found similar results: 1.2% of 424 NSCLCs had ROS1 rearrangements. Thet suggest ROS1 inhibition may be an effective treatment strategy for the subset of patients with NSCLC whose tumors express ROS1 fusion genes.

Research Indicators

Publications Per Year (1992-2017)
Graph generated 16 March 2017 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Antineoplastic Agents
  • Angiogenesis
  • Molecular Targeted Therapy
  • Mutation
  • Protein-Tyrosine Kinases
  • Non-Small Cell Lung Cancer
  • Lung Cancer
  • CD74
  • SLC34A2
  • X-Ray Computed Tomography
  • Proto-Oncogene Proteins
  • Precision Medicine
  • Immunohistochemistry
  • Gene Fusion
  • Oncogenes
  • Brain and CNS Tumours
  • Staging
  • Sequence Homology, Nucleic Acid
  • Protein Kinase Inhibitors
  • GOPC
  • Protein-Serine-Threonine Kinases
  • c-MET
  • United States Food and Drug Administration
  • Proto-Oncogene Proteins p21(ras)
  • High-Throughput Nucleotide Sequencing
  • Genetic Predisposition
  • BRAF
  • Pyrazoles
  • Chromosome 6
  • FISH
  • Disease-Free Survival
  • Receptor, erbB-2
  • Phenotype
  • Drug Resistance
  • Xenograft Models
  • Oncogene Fusion Proteins
  • Gene Rearrangement
  • DNA Mutational Analysis
  • Cell Proliferation
  • ras Proteins
  • FGFR1
  • Adenocarcinoma
  • ROS1
  • Cancer Gene Expression Regulation
  • Biomarkers, Tumor
Tag cloud generated 16 March, 2017 using data from PubMed, MeSH and CancerIndex

Specific Cancers (5)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: ROS1 (cancer-related)

Socinski MA, Pennell NA
Best Practices in Treatment Selection for Patients With Advanced NSCLC.
Cancer Control. 2016; 23(4 Suppl):2-14 [PubMed] Related Publications
Worldwide, lung cancer is the most prevalent form of cancer, and its non-small-cell subtype constitutes up to 85% of cases. Overall, lung cancer is the most common cause of cancer-related death in the United States for both sexes, and its 5-year survival rate is 17%. It is a heterogeneous disease characterized by a variety of biomarkers and differing histologies. Non-small-cell lung cancer may be squamous or nonsquamous in nature and fueled by a number of oncodrivers. Obtaining sufficient tissue during biopsy to perform thorough biomarker testing is a challenge but essential for the modern, targeted therapeutic environment. Although platinum-based doublets still play a major role in first-line treatment, novel therapeutic agent targeting BRAF, EGFR, ALK, and ROS1, as well as agents targeting the T790M mutation, may offer options for patients whose disease fails to respond to initial therapy or relapses following an initial response. The emergence of immunotherapy as second-line standard therapy has changed the treatment paradigm. Some patients will have more favorable outcomes in the first-line setting with immunotherapy. However, managing lung cancer has become more complex than it was 15 years ago when the challenge of treatment was seen as being only binary, ie, small-cell vs non-small-cell disease.

Zhong E, Huang H
Crizotinib in ROS1 rearranged non-small cell lung cancer (NSCLC), from response to resistance.
BMJ Case Rep. 2016; 2016 [PubMed] Related Publications
We examined an immediate, but short-lived, response to crizotinib, a drug with a new indication for ROS1 rearranged non-small cell lung cancer (NSCLC) in a middle-aged non-smoker. The patient presented with metastatic NSCLC and extensive disease in multiple organs. He was treated with crizotinib 250 mg twice a day. Within 2-3 days, his condition rapidly improved, which was evident in a CT scan 2 months later. However, after 3 months of treatment, his condition deteriorated dramatically. The patient did not respond to ceritinib, a second-line drug that targets anaplastic lymphoma kinase, and died shortly after. This case demonstrated an impressive but brief response to crizotinib.

Bosman FT
In this issue.
Virchows Arch. 2016; 469(5):487-488 [PubMed] Related Publications

Bubendorf L, Büttner R, Al-Dayel F, et al.
Testing for ROS1 in non-small cell lung cancer: a review with recommendations.
Virchows Arch. 2016; 469(5):489-503 [PubMed] Free Access to Full Article Related Publications
Rearrangements of the ROS1 gene occur in 1-2 % of non-small cell lung cancers (NSCLCs). Crizotinib, a highly effective inhibitor of ROS1 kinase activity, is now FDA-approved for the treatment of patients with advanced ROS1-positive NSCLC. Consequently, focus on ROS1 testing is growing. Most laboratories currently rely on fluorescence in situ hybridisation (FISH) assays using a dual-colour break-apart probe to detect ROS1 rearrangements. Given the rarity of these rearrangements in NSCLC, detection of elevated ROS1 protein levels by immunohistochemistry may provide cost-effective screening prior to confirmatory FISH testing. Non-in situ testing approaches also hold potential as stand-alone methods or complementary tests, including multiplex real-time PCR assays and next-generation sequencing (NGS) platforms which include commercial test kits covering a range of fusion genes. In order to ensure high-quality biomarker testing, appropriate tissue handling, adequate control materials and participation in external quality assessment programmes are essential, irrespective of the testing technique employed. ROS1 testing is often only considered after negative tests for EGFR mutation and ALK gene rearrangement, based on the assumption that these oncogenic driver events tend to be exclusive. However, as the use of ROS1 inhibitors becomes routine, accurate and timely detection of ROS1 gene rearrangements will be critical for the optimal treatment of patients with NSCLC. As NGS techniques are introduced into routine diagnostic practice, ROS1 fusion gene testing will be provided as part of the initial testing package.

Xu Y, Zhu C, Qian W, Zheng M
Comprehensive study of mutational and clinicopathologic characteristics of adenocarcinoma with lepidic pattern in surgical resected lung adenocarcinoma.
J Cancer Res Clin Oncol. 2017; 143(1):181-186 [PubMed] Related Publications
PURPOSE: Although many studies have explored clinicopathologic characteristics and prognosis of lung adenocarcinoma, a few literatures reported the mutational status of lung adenocarcinomas with lepidic pattern and whether there is difference between adenocarcinomas with pure lepidic component and lepidic predominant adenocarcinomas remain unknown.
METHODS: One hundred and thirty-three patients including 92 adenocarcinomas with pure lepidic component and 41 lepidic predominant adenocarcinomas were subjected to the study. All the clinicopathologic data, the follow-up information and the status of gene mutations including EGFR, KRAS, HER2, BRAF, AKT1, ALK, RET and ROS1 were investigated.
RESULTS: Of the 133 lung adenocarcinomas with lepidic pattern, 87.22 % (116/133) were detected harboring mutations in our tested genes, among which 90.52 % (105/116) harbored EGFR mutation. There are three KRAS mutations and two BRAF mutations in our cohort, and we revealed two ALK fusion and one RET fusion. No ROS1 fusion was discovered. There was no significant difference in gene mutations between adenocarcinomas with pure lepidic component and lepidic predominant adenocarcinomas except EGFR mutation (p = 0.039). Lepidic predominant adenocarcinomas seemed to have more EGFR mutation. The post-recurrence survival was significantly prolonged in patients who received TKIs.
CONCLUSIONS: Adenocarcinoma with lepidic pattern is a low-grade lung tumor with favorable prognosis and displays frequent EGFR mutation. Compared with lepidic predominant adenocarcinomas, lung adenocarcinomas with pure lepidic component have a better prognosis. On the basis of these results, we also suggested the application of EGFR-TKIs therapy for EGFR mutation-positive patients after recurrence could achieve prolonged survival.

Caccese M, Ferrara R, Pilotto S, et al.
Current and developing therapies for the treatment of non-small cell lung cancer with ALK abnormalities: update and perspectives for clinical practice.
Expert Opin Pharmacother. 2016; 17(17):2253-2266 [PubMed] Related Publications
INTRODUCTION: The treatment of patients with ALK-rearranged non-small-cell lung cancer was completely revolutionized by the introduction of Crizotinib, a small molecule inhibiting ALK, MET and ROS1. Given that resistance occurs within approximately 12 months, in order to develop more potent inhibitors and to increase drug penetration to CNS, innovative ALK-inhibitors were developed. Second-generation ALK inhibitors Ceritinib (LDK378), Alectinib (CH5424802/RO5424802) and Brigatinib (AP26113) have shown significant clinical activity, and were rapidly approved by regulatory agencies. In addition, early clinical data demonstrated that 3(rd) generation ALK-inhibitors Lorlatinib (PF-06463922), Entrectinib (RxDx-101) and Ensartinib (X-398) provided promising advantages in terms of both clinical activity and safety. Areas covered: In this review, the efficacy and tolerability of Crizotinib for 1(st) and 2(nd)-line treatment, and the clinical and preclinical data that led to the development of innovative second and third generation ALK-inhibitors are described. Expert opinion: The better characterization of the mechanisms of resistance to Crizotinib led to the development of newest drugs, which are active both after Crizotinib failure and in patients naïve from ALK-inhibitors. Tumor characterization at disease progression will allow to further personalize the treatment by establishing optimal sequences, which represent tough challenges for the future research in this field of cancer treatment.

Hirsch FR, Suda K, Wiens J, Bunn PA
New and emerging targeted treatments in advanced non-small-cell lung cancer.
Lancet. 2016; 388(10048):1012-24 [PubMed] Related Publications
Targeted therapies are substantially changing the management of lung cancers. These treatments include drugs that target driver mutations, those that target presumed important molecules in cancer cell proliferation and survival, and those that inhibit immune checkpoint molecules. This area of research progresses day by day, with novel target discoveries, novel drug development, and use of novel combination treatments. Researchers and clinicians have also extensively investigated the predictive biomarkers and the molecular mechanisms underlying inherent or acquired resistance to these targeted therapies. We review recent progress in the development of targeted treatments for patients with advanced non-small-cell lung cancer, especially focusing on data from published clinical trials.

Zhou F, Moreira AL
Lung Carcinoma Predictive Biomarker Testing by Immunoperoxidase Stains in Cytology and Small Biopsy Specimens: Advantages and Limitations.
Arch Pathol Lab Med. 2016; 140(12):1331-1337 [PubMed] Related Publications
CONTEXT: - In the burgeoning era of molecular genomics, immunoperoxidase (IPOX) testing grows increasingly relevant as an efficient and effective molecular screening tool. Patients with lung carcinoma may especially benefit from the use of IPOX because most lung carcinomas are inoperable at diagnosis and only diagnosed by small tissue biopsy or fine-needle sampling. When such small specimens are at times inadequate for molecular testing, positive IPOX results still provide actionable information.
OBJECTIVE: - To describe the benefits and pitfalls of IPOX in the detection of biomarkers in lung carcinoma cytology specimens and small biopsies by summarizing the currently available commercial antibodies, preanalytic variables, and analytic considerations.
DATA SOURCES: - PubMed.
CONCLUSIONS: - Commercial antibodies exist for IPOX detection of aberrant protein expression due to EGFR L858R mutation, EGFR E746_A750 deletion, ALK rearrangement, ROS1 rearrangement, and BRAF V600E mutation, as well as PD-L1 expression in tumor cells. Automated IPOX protocols for ALK and PD-L1 detection were recently approved by the Food and Drug Administration as companion diagnostics for targeted therapies, but consistent interpretive criteria remain to be elucidated, and such protocols do not yet exist for other biomarkers. The inclusion of cytology specimens in clinical trials would expand patients' access to testing and treatment, yet there is a scarcity of clinical trial data regarding the application of IPOX to cytology, which can be attributed to trial designers' lack of familiarity with the advantages and limitations of cytology. The content of this review may be used to inform clinical trial design and advance IPOX validation studies.

Savic S, Bubendorf L
Common Fluorescence In Situ Hybridization Applications in Cytology.
Arch Pathol Lab Med. 2016; 140(12):1323-1330 [PubMed] Related Publications
CONTEXT: - Fluorescence in situ hybridization (FISH) is a well-established method for detection of genomic aberrations in diagnostic, prognostic, and predictive marker testing.
OBJECTIVE: - To review common applications of FISH in cytology.
DATA SOURCES: - The published literature was reviewed.
CONCLUSIONS: - Cytology is particularly well suited for all kinds of FISH applications, which is highlighted in respiratory tract cytology with an increasing demand for predictive FISH testing in lung cancer. Fluorescence in situ hybridization is the gold standard for detection of predictive anaplastic lymphoma kinase gene (ALK) rearrangements, and the same evaluation criteria as in histology apply to cytology. Several other gene rearrangements, including ROS proto-oncogene 1 receptor tyrosine kinase (ROS1), are becoming clinically important and share the same underlining cytogenetic mechanisms with ALK. MET amplification is one of the most common mechanisms of acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors and can be targeted by crizotinib. As genomic aberrations are a hallmark of malignant cells, FISH is a valuable objective ancillary diagnostic tool. In urinary tract cytology, atypical urothelial cells equivocal for malignancy are a common diagnostic dilemma and multitarget FISH can help clarify such cells. Diagnosis of malignant mesothelioma remains one of the most challenging fields in effusion cytology, and ancillary FISH is useful in establishing the diagnosis. Fluorescence in situ hybridization is a morphology-based technique, and the prerequisite for reliable FISH results is a targeted evaluation of the cells in question (eg, cancer or atypical cells). Cytopathologists and cytotechnicians should therefore be involved in molecular testing in order to select the best material and to provide their morphologic expertise.

Kim J, Jang SJ, Choi CM, Ro JY
Correlation of Histologic Subtypes and Molecular Alterations in Pulmonary Adenocarcinoma: Therapeutic and Prognostic Implications.
Adv Anat Pathol. 2016; 23(5):330-8 [PubMed] Related Publications
Major driver mutations of pulmonary adenocarcinomas have been identified and highlighted as actionable targets for precision cancer medicine. As phenotype is largely determined by genotype, genetic changes associated with morphologic features have recently received more attention from both pathologists and clinicians. The morphologic features of adenocarcinomas with mutations in EGFR or KRAS, or translocated ALK, have rarely been described. Pulmonary adenocarcinomas with EGFR mutations, the most common driver mutation encountered in Asian patients with pulmonary adenocarcinoma, show lepidic or papillary organotypic growth patterns. KRAS-mutated adenocarcinomas demonstrate nonorganotypic growth patterns, especially mucin-containing cells. P53 mutations are associated with aggressiveness rather than growth patterns. HER2 mutations are observed in mucinous adenocarcinoma and adenocarcinoma with micropapillary features. The histologic features of BRAF-mutated adenocarcinomas have not yet been established, but papillary, lepidic, solid, and acinar patterns have been observed. Adenocarcinomas with rearrangement of ALK, ROS1, and RET genes share similar histologic features, such as solid signet-ring cells and cribriform formation. However, adenocarcinomas with NRG1 rearrangements frequently show mucinous morphology. The histologic features and related mutations of adenocarcinomas with expression of programmed cell death-1 and programmed cell death ligands-1 may be helpful in guiding immunotherapeutic treatment. This review describes histopathologic features of adenocarcinomas and their correlation with molecular alterations.

Lee CY, Sholl LM, Zhang B, et al.
Atypical Spitzoid Neoplasms in Childhood: A Molecular and Outcome Study.
Am J Dermatopathol. 2017; 39(3):181-186 [PubMed] Related Publications
The natural history of atypical Spitz neoplasms remains poorly understood, resulting in significant patient and clinician anxiety. We sought to better characterize outcomes that correlated with molecular features by performing a prospective cohort study of pediatric atypical spitzoid neoplasms in which fluorescence in situ hybridization studies were obtained for diagnosis. Cases with sufficient tissue underwent additional retrospective assessment for translocations in ALK, NTRK1, BRAF, RET, and ROS1. Among 246 total patients assessed, 13% had a positive fluorescence in situ hybridization result. Follow-up data was available in 85 patients. Two patients had a recurrence of whom 1 had distant metastasis. Both patients had homozygous deletions in 9p21. Homozygous deletions in 9p21 significantly correlated with recurrence of disease (P = 0.027). Fifteen (36%) of 42 cases were found to have a kinase fusion protein. However, the presence of kinase fusions was nonprognostic of recurrence (P > 0.99). This study was limited by the availability and length of follow-up data and the number of adverse outcomes. The majority of atypical spitzoid neoplasms in childhood have indolent behavior. Although the subgroup of patients with homozygous deletions in 9p21 is at higher risk for aggressive clinical behavior, their prognosis seems considerably better than similarly staged conventional melanoma.

Uguen A, De Braekeleer M
ROS1 fusions in cancer: a review.
Future Oncol. 2016; 12(16):1911-28 [PubMed] Related Publications
The ROS1 gene belongs to the sevenless subfamily of tyrosine kinase insulin receptor genes. A literature review identified a ROS1 fusion in 2.54% of the patients with lung adenocarcinoma and even higher frequencies in spitzoid neoplasms and inflammatory myofibroblastic tumors. At present, 26 genes were found to fuse with ROS1, some of them already known to fuse with RET and ALK. All the fusion proteins retain the ROS1 kinase domain, but rarely its transmembrane domain. Most of the partners have dimerization domains that are retained in the fusion, presumably leading to constitutive ROS1 tyrosine kinase activation. Some partners have transmembrane domains that are retained or not in the chimeric proteins. Therefore, different ROS1 fusions have distinct subcellular localization, suggesting that they may activate different substrates in vivo.

Guisier F, Salaün M, Lachkar S, et al.
Molecular analysis of peripheral non-squamous non-small cell lung cancer sampled by radial EBUS.
Respirology. 2016; 21(4):718-26 [PubMed] Related Publications
BACKGROUND AND OBJECTIVE: Treatment optimization of non-squamous non-small-cell lung cancers (nonSq-NSCLC) relies on the molecular analysis of the tumour. We aimed to assess the predictive factors of molecular analysis feasibility (MAF) from samples of peripheral nonSq-NSCLC obtained by radial endobronchial ultrasound bronchoscopy (r-EBUS) and 1.5 mm microbiopsy forceps.
METHODS: We reviewed data from consecutive peripheral lung nodules sampled with r-EBUS between January 2012 and July 2014 at a single French University Hospital. nonSq-NSCLC were systematically analysed for EGFR, KRAS, ALK, HER2, PI3K and BRAF throughout the study, and c-MET and ROS1 alterations for the last 10 months.
RESULTS: Of 111 nonSq-NSCLC diagnosed by r-EBUS (113 procedures, mean nodule diameter 28 ± 15 mm), 88 were analysed for EGFR and ALK, 87 for KRAS, 86 for HER2, PI3K and BRAF and 14 for c-MET. Forty-one mutations were identified (23 KRAS, 10 EGFR, 2 BRAF, 1 HER2 and 5 ALK rearrangements). Four c-MET overexpressions were noted. MAF rose from 67% for the first 57 procedures to 89% for the last 56 procedures (P = 0.02) likely due to a higher number of biopsies performed (2 ± 1 vs 3 ± 2, P = 0.005). Upper or middle lobe location (OR 1.19, 95% CI: 1.02-1.38, P = 0.03), and at least three biopsies (OR 1.20, 95% CI: 1.04-1.40, P = 0.02) were predictive factors of MAF. Percentage of tumour cells, size of lesion and distance to the pleura did not correlate with MAF.
CONCLUSION: Multi-gene molecular analysis could be performed in nearly 80% of paraffin-embedded biopsies or smear specimens sampled by r-EBUS assisted bronchoscopy of peripheral tumoral lung nodules.

Ju L, Han M, Zhao C, Li X
EGFR, KRAS and ROS1 variants coexist in a lung adenocarcinoma patient.
Lung Cancer. 2016; 95:94-7 [PubMed] Related Publications
The c-ros oncogene 1 (ROS1) fusion is almost mutually exclusive to epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK) or Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation in non-small cell lung cancer (NSCLC), and it is not seen in the literature for patients to exhibit three mutations. The present study reported a case of a 53-year-old male diagnosed with adenocarcinoma, exhibiting combined EGFR, KRAS mutations and ROS1 rearrangement. At the first line therapy, the patient was treated with crizotinib because of the KRAS mutation that is a known resistant factor of EGFR-TKI resistance, but no responsive. At the second line therapy, EGFR-TKI Icotinib revealed a good response until now. To the best of to our knowledge, this is the first case report of a patient with concurrent EGFR, KRAS mutations and ROS1 fusion. This patient had an excellent response to Icotinib but not crizotinib, suggesting that the EGFR mutation was the oncogenic driver but ROS1 fusion and KRAS mutation not.

Tiash S, Chua MJ, Chowdhury EH
Knockdown of ROS1 gene sensitizes breast tumor growth to doxorubicin in a syngeneic mouse model.
Int J Oncol. 2016; 48(6):2359-66 [PubMed] Related Publications
Treatment of breast cancer, the second leading cause of female deaths worldwide, with classical drugs is often accompanied by treatment failure and relapse of disease condition. Development of chemoresistance and drug toxicity compels compromising the drug concentration below the threshold level with the consequence of therapeutic inefficacy. Moreover, amplification and over-activation of proto-oncogenes in tumor cells make the treatment more challenging. The oncogene, ROS1 which is highly expressed in diverse types of cancers including breast carcinoma, functions as a survival protein aiding cancer progression. Thus we speculated that selective silencing of ROS1 gene by carrier-mediated delivery of siRNA might sensitize the cancer cells to the classical drugs at a relatively low concentration. In this investigation we showed that intracellular delivery of c-ROS1-targeting siRNA using pH-sensitive inorganic nanoparticles of carbonate apatite sensitizes mouse breast cancer cells (4T1) to doxorubicin, but not to cisplatin or paclitaxel, with the highest enhancement in chemosensitivity obtained at 40 nM of the drug concentration. Although intravenous administrations of ROS1-loaded nanoparticles reduced growth of the tumor, a further substantial effect on growth retardation was noted when the mice were treated with the siRNA- and Dox-bound particles, thus suggesting that silencing of ROS1 gene could sensitize the mouse breast cancer cells both in vitro and in vivo to doxorubicin as a result of synergistic effect of the gene knockdown and the drug action, eventually preventing activation of the survival pathway protein, AKT1. Our findings therefore provide valuable insight into the potential cross-talk between the pathways of ROS1 and doxorubicin for future development of effective therapeutics for breast cancer.

Chen LF, Chen XY, Yu XB
[Correlation of clinicopathologic features and driver gene mutation in non-small cell lung cancer].
Zhonghua Bing Li Xue Za Zhi. 2016; 45(4):221-5 [PubMed] Related Publications
OBJECTIVE: To study the relationship between mutations of well-known driver genes and clinicopathologic characteristics of non-small cell lung cancers (NSCLC).
METHODS: Scorpions amplification refractory mutation system (scorpions ARMS) fluorescence quantitative PCR was performed to investigate 205 driver gene mutation status in NSCLC in correlation with clinicopathological characteristics of the patients.
RESULTS: Driver gene mutations were detected in 146 of 205 (71.2%) patients with NSCLC, including 81.7%(138/169) adenocarcinomas, in which mutations of nine genes were found: EGFR (63.3%, 107/169), KRAS (5.9%, 10/169), PIK3CA (4.1%, 7/169), ALK (4.1%, 7/169), ROS1 (3.0%, 5/169), RET (3.6%, 6/169), HER2 (1.8%, 3/169), NRAS (0.6%, 1/169) and BRAF (0.6%, 1/169). The frequencies of driver gene mutations were higher in adenocarcinomas, female patients and non-smokers (P<0.01, P=0.003, P<0.01, respectively). Driver gene mutation status showed no correlation with either the age or the clinical stage (P=0.281, P=0.490, respectively). However, EGFR mutations tended to occur in adenocarcinoma, female, non-smokers, and patients of ≥62 years of age (P<0.01, P<0.01, P=0.002, P=0.012, respectively). The frequency of EGFR mutation was positively correlated with the tumor histology of lepidic, acinar, papillary and micropapillary predominant growth patterns. There was no relationship between EGFR mutation and the clinical stage (P=0.237). The frequency of KRAS mutation was higher in solid predominant and invasive mucinous adenocarcinomas (P=0.015); that of PIK3CA mutation was higher in patients of ≥62 years of age, invasive mucinous adenocarcinoma and fetal adenocarcinoma (P=0.015, P=0.006, respectively). ALK, ROS1 or RET mutation positive NSCLC tended to occur in nonsmokers and have solid predominant tumors and invasive mucinous adenocarcinoma (P=0.012, P=0.017 respectively). The frequency of EML4-ALK mutation was higher in the early stage patients with solid predominant tumors and invasive mucinous adenocarcinomas (P=0.025, P=0.014, respectively); that of ROS1 rearrangement was higher in invasive mucinous adenocarcinomas (P=0.049). NRAS, BRAF and HER2 gene mutations were infrequent and their clinical significance remained to be elucidated.
CONCLUSIONS: The relationship between mutations of well-known driver genes and clinicopathological characteristics in patients with NSCLC has diversity, the rate of mutations is higher in non-smoking female patients with adenocarcinoma.

Saito M, Shiraishi K, Kunitoh H, et al.
Gene aberrations for precision medicine against lung adenocarcinoma.
Cancer Sci. 2016; 107(6):713-20 [PubMed] Free Access to Full Article Related Publications
Lung adenocarcinoma (LADC), the most frequent histological type of lung cancer, is often triggered by an aberration in a driver oncogene in tumor cells. Examples of such aberrations are EGFR mutation and ALK fusion. Lung adenocarcinoma harboring such mutations can be treated with anticancer drugs that target the aberrant gene products. Additional oncogene aberrations, including RET, ROS1, and NRG1 fusions, skipping of exon 14 of MET, and mutations in BRAF, HER2, NF1, and MEK1, were recently added to the list of such "druggable" driver oncogene aberrations, and their responses to targeted therapies are currently being evaluated in clinical trials. However, approximately 30% and 50% of LADCs in patients in Japan and Europe/USA, respectively, lack the driver oncogene aberrations listed above. Therefore, novel therapeutic strategies, such as those that exploit the vulnerabilities of cancer cells with non-oncogene aberrations, are urgently required. This review summarizes the current status of research on precision medicine against LADC and enumerates the research priorities for the near future.

Gao E, Zhao J, Zhuo M, et al.
[Clinical Efficacy of Crizotinib in Treatment of Patients with Advanced NSCLC].
Zhongguo Fei Ai Za Zhi. 2016; 19(3):161-8 [PubMed] Related Publications
BACKGROUND AND OBJECTIVE: Crizotinib was developed in recent years based on targets of anaplastic lymphoma kinase (ALK) fusion genes. The aim of this study is to explore the efficacy of crizotinib in treatment of non-small cell lung cancer (NSCLC) with ALK/ROS1 rearrangement.
METHODS: Retrospective analysis of 40 patients with ALK/ROS1-positive NSCLC, who received treatment in Beijing Cancer Hospital during the period from Jun. 2013 to Dec. 2014.
RESULTS: Among these cases, 39 were adenocarcinoma and adenosquamous carcinoma, with characters involving signet-ring cell carcinoma, polypoid adenocarcinoma, acini and papillary adenocarcinoma. The median age was 49.5 years old, with the overall response rate of 62.5% and disease control rate of 95.0%. Of all the cases, median follow-up was 14.6 months and median PFS 7.5 months; median OS has not been reached; the one-year survival rate was 77.4%. The median PFS and OS of patients receiving first and second-line treatment tend to be longer than those who received post-second line treatment, but with no statistical significance (PFS: 9 mo vs 6 mo, P=0.06; OS: 21.5 mo vs 14.6 mo, P=0.12). Twenty patients who experienced progression in brain metastases. After experiencing progression, the patients receiving 2nd/3rd generation ALK-TKI treatment showed efficacy of disease control and survival. The adverse events include gastrointestinal reaction, transaminase elevation, and distinctive visual abnormalities, etc.
CONCLUSION: The clinical features, efficacy, and adverse events of crizotinib in the treatment of the 40 patients with ALK/ROS1-positive NSCLC are similar to the data from the previous reports. The most common site of progression was brain metastases. The treatment of crizotinib-resistant patients using 2nd/3rd generation ALK-TKI could delay progression.

Allison DB, Lilo MT, Geddes S, et al.
Detection of PIK3CA mutations, including a novel mutation of V344G in exon 4, in metastatic lung adenocarcinomas: A retrospective study of 115 FNA cases.
Cancer Cytopathol. 2016; 124(7):485-92 [PubMed] Related Publications
BACKGROUND: Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutations and amplification are detected in 1% of primary lung adenocarcinomas (ADCs) and in 38% of primary lung squamous cell carcinomas. Alterations of PIK3CA in metastatic non-small cell lung carcinoma (NSCLC), however, are still not fully understood. This study investigated PIK3CA alterations in metastatic ADCs and correlated the findings with those for other commonly tested molecular abnormalities via fine-needle aspiration (FNA) and small-core biopsy materials.
METHODS: This study identified 115 FNA cases of metastatic lung ADC with standard lung cancer panel analysis by targeted next-generation sequencing and fluorescence in situ hybridization at the Johns Hopkins Medical Institute over a 12-month period. The panel included mutational analysis of PIK3CA, AKT, BRAF, EGFR, ERBB2, KRAS, and NRAS genes and tests of rearrangements for ALK and ROS1 genes.
RESULTS: A PIK3CA mutation was detected in 7 of 115 cases of metastatic ADC (6.1%). The majority of the mutations were located in exon 9 or exon 20; however, a mutation in exon 1 was seen in 1 case. Furthermore, p.V344G in exon 4 was detected in 2 cases. Among cases with PIK3CA mutations, 4 had coexisting EGFR mutations, whereas 2 had a coexisting BRAF or KRAS mutation.
CONCLUSIONS: Several common mutations as well as a novel mutation in the PIK3CA gene were observed in metastatic NSCLC (particularly ADC). The unique role, however, of PIK3CA mutations in metastatic NSCLC and the clinical implications need to be further investigated. Cancer Cytopathol 2016;124:485-92. © 2016 American Cancer Society.

Menichincheri M, Ardini E, Magnaghi P, et al.
Discovery of Entrectinib: A New 3-Aminoindazole As a Potent Anaplastic Lymphoma Kinase (ALK), c-ros Oncogene 1 Kinase (ROS1), and Pan-Tropomyosin Receptor Kinases (Pan-TRKs) inhibitor.
J Med Chem. 2016; 59(7):3392-408 [PubMed] Related Publications
Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase responsible for the development of different tumor types. Despite the remarkable clinical activity of crizotinib (Xalkori), the first ALK inhibitor approved in 2011, the emergence of resistance mutations and of brain metastases frequently causes relapse in patients. Within our ALK drug discovery program, we identified compound 1, a novel 3-aminoindazole active on ALK in biochemical and in cellular assays. Its optimization led to compound 2 (entrectinib), a potent orally available ALK inhibitor active on ALK-dependent cell lines, efficiently penetrant the blood-brain barrier (BBB) in different animal species and highly efficacious in in vivo xenograft models. Moreover, entrectinib resulted to be strictly potent on the closely related tyrosine kinases ROS1 and TRKs recently found constitutively activated in several tumor types. Entrectinib is currently undergoing phase I/II clinical trial for the treatment of patients affected by ALK-, ROS1-, and TRK-positive tumors.

Zhao W, Choi YL, Song JY, et al.
ALK, ROS1 and RET rearrangements in lung squamous cell carcinoma are very rare.
Lung Cancer. 2016; 94:22-7 [PubMed] Related Publications
OBJECTIVES: Chromosomal rearrangements of ALK and ROS1 genes in non-small cell lung carcinoma (NSCLC) define a molecular subgroup of lung adenocarcinoma (ADC) that is amenable to targeted therapy with tyrosine kinase inhibitors (TKIs) crizotinib. Emerging clinical studies have demonstrated that patients with RET-rearranged NSCLC may also benefit from existing RET TKIs, including cabozantinib and vandetanib. However, the reported cases of lung squamous cell carcinomas (SCC) harboring gene rearrangements have been detected via fluorescence in situ hybridization (FISH) or immunohistochemistry (IHC) from materials such as biopsy or resection. Fusion events identified in lung SCC raise the question of whether this histologic subtype should also be evaluated for merit molecular testing. This work was undertaken to study the prevalence of lung SCC harboring ALK, ROS1, and RET translocations.
MATERIALS AND METHODS: Squamous cell carcinomas were confirmed using both histological examination by pathologists and immunohistochemistry analysis with positive staining of P63 and CK5/6 combined with negative CK7 and TTF-1 staining. 214 samples from surgically resected patient tissues were used to search for ALK, ROS1, and RET rearrangements by a NanoString analysis method. Fusion events were detected in a single-tube, multiplex assay system that relied on a complementary strategy of interrogation of 3' gene overexpression and detection of specific fusion transcript variants.
RESULTS AND CONCLUSION: ALK, ROS1 or RET gene rearrangements appeared 0 times out of 214 cases of lung SCC. Our data revealed that these fusions may be very rare in lung squamous cancer. The molecular screening strategy should therefore be focused on lung adenocarcinoma as the current National Comprehensive Cancer Network (NCCN) guideline recommends.

Inoue M, Toki H, Matsui J, et al.
Mouse models for ROS1-fusion-positive lung cancers and their application to the analysis of multikinase inhibitor efficiency.
Carcinogenesis. 2016; 37(5):452-60 [PubMed] Related Publications
ROS1-fusion genes, resulting from chromosomal rearrangement, have been reported in 1-2% of human non-small cell lung cancer cases. More than 10 distinct ROS1-fusion genes, including break-point variants, have been identified to date. In this study, to investigate the in vivo oncogenic activities of one of the most frequently detected fusions, CD74-ROS1, as well as another SDC4-ROS1 fusion that has also been reported in several studies, we generated transgenic (TG) mouse strains that express either of the two ROS1-fusion genes specifically in lung alveolar type II cells. Mice in all TG lines developed tumorigenic nodules in the lung, and a few strains of both TG mouse lines demonstrated early-onset nodule development (multiple tumor lesions present in the lung at 2-4 weeks after birth); therefore, these two strains were selected for further investigation. Tumors developed progressively in the untreated TG mice of both lines, whereas those receiving oral administration of an ALK/MET/ROS1 inhibitor, crizotinib, and an ALK/ROS1 inhibitor, ASP3026, showed marked reduction in the tumor burden. Collectively, these data suggest that each of these two ROS1-fusion genes acts as a driver for the pathogenesis of lung adenocarcinoma in vivo The TG mice developed in this study are expected to serve as valuable tools for exploring novel therapeutic agents against ROS1-fusion-positive lung cancer.

Subbiah V, Hong DS, Meric-Bernstam F
Clinical activity of ceritinib in ROS1-rearranged non-small cell lung cancer: Bench to bedside report.
Proc Natl Acad Sci U S A. 2016; 113(11):E1419-20 [PubMed] Free Access to Full Article Related Publications

Svaton M, Pešek M
[Successful Therapy of Czech Patients with ROS1 Translocation by Crizotinib].
Klin Onkol. 2016; 29(1):63-5 [PubMed] Related Publications
Targeted therapy of lung cancer has brought significant improvement in prognosis for a lot of patients with EGFR-sensitive mutations and ALK translocations. Other clinical studies have shown ROS1 translocation as another potential target. Our case report brings probably the first successful use of crizotininib in a patient with ROS1 translocation in the Czech Republic. Treatment was well-tolerated and persists continually. During the control PET/ CT scans, partial regression of the disease was observed. ROS1 translocation becomes another promising target for our patients. Therefore, in our opinion, serious discussion about its inclusion among the basic genetic testing in lung adenocarcinomas should occur.

Katayama R, Sakashita T, Yanagitani N, et al.
P-glycoprotein Mediates Ceritinib Resistance in Anaplastic Lymphoma Kinase-rearranged Non-small Cell Lung Cancer.
EBioMedicine. 2016; 3:54-66 [PubMed] Free Access to Full Article Related Publications
The anaplastic lymphoma kinase (ALK) fusion oncogene is observed in 3%-5% of non-small cell lung cancer (NSCLC). Crizotinib and ceritinib, a next-generation ALK tyrosine kinase inhibitor (TKI) active against crizotinib-refractory patients, are clinically available for the treatment of ALK-rearranged NSCLC patients, and multiple next-generation ALK-TKIs are currently under clinical evaluation. These ALK-TKIs exhibit robust clinical activity in ALK-rearranged NSCLC patients; however, the emergence of ALK-TKI resistance restricts the therapeutic effect. To date, various secondary mutations or bypass pathway activation-mediated resistance have been identified, but large parts of the resistance mechanism are yet to be identified. Here, we report the discovery of p-glycoprotein (P-gp/ABCB1) overexpression as a ceritinib resistance mechanism in ALK-rearranged NSCLC patients. P-gp exported ceritinib and its overexpression conferred ceritinib and crizotinib resistance, but not to PF-06463922 or alectinib, which are next-generation ALK inhibitors. Knockdown of ABCB1 or P-gp inhibitors sensitizes the patient-derived cancer cells to ceritinib, in vitro and in vivo. P-gp overexpression was identified in three out of 11 cases with in ALK-rearranged crizotinib or ceritinib resistant NSCLC patients. Our study suggests that alectinib, PF-06463922, or P-gp inhibitor with ceritinib could overcome the ceritinib or crizotinib resistance mediated by P-gp overexpression.

Veldore VH, Patil S, Satheesh CT, et al.
Genomic profiling in a homogeneous molecular subtype of non-small cell lung cancer: An effort to explore new drug targets.
Indian J Cancer. 2015 Apr-Jun; 52(2):243-8 [PubMed] Related Publications
BACKGROUND: Patients' who are positive for kinase domain activating mutations in epidermal growth factor receptor (EGFR) gene, constitute 30-40% of non-small cell lung cancer (NSCLC), and are suitable candidates for Tyrosine Kinase Inhibitor based targeted/personalized therapy. In EGFR non-mutated subset, 8-10% that show molecular abnormalities such as EML4-ALK, ROS1-ALK, KIP4-ALK, may also derive the benefit of targeted therapy. However, 40% of NSCLC belong to a grey zone of tumours that are negative for the clinically approved biomarkers for personalized therapy. This pilot study aims to identify and classify molecular subtypes of this group to address the un-met need for new drug targets in this category. Here we screened for known/novel oncogenic driver mutations using a 46 gene Ampliseq Panel V1.0 that includes Ser/Thr/Tyr kinases, transcription factors and tumor suppressors.
METHODS: NSCLC with tumor burden of at least 40% on histopathology were screened for 29 somatic mutations in the EGFR kinase domain by real-time polymerase chain reaction methods. 20 cases which were EGFR non-mutated for TK domain mutations were included in this study. DNA Quality was verified from each of the 20 cases by fluorimeter, pooled and subjected to targeted re-sequencing in the Ion Torrent platform. Torrent Suite software was used for next generation sequencing raw data processing and variant calling.
RESULTS: The clinical relevance and pathological role of all the mutations/variants that include SNPs and Indels was assessed using polyphen-2/SIFT/PROVEAN/mutation assessor structure function prediction programs. There were 10 pathogenic mutations in six different oncogenes for which annotation was available in the COSMIC database; C420R mutation in PIK3CA, Q472H mutation in vascular endothelial growth factor receptor 2 (VEGFR2) (KDR), C630W and C634R in RET, K367M mutation in fibroblast growth factor receptor 2 (FGFR2), G12C in KRAS and 4 pathogenic mutations in TP53 in the DNA binding domain (E285K, R213L, R175H, V173G).
CONCLUSION: Results suggest, a potential role for PIK3CA, VEGFR2, RET and FGFR2 as therapeutic targets in EGFR non-mutated NSCLC that requires further clinical validation.

Liang W, He Q, Chen Y, et al.
Metastatic EML4-ALK fusion detected by circulating DNA genotyping in an EGFR-mutated NSCLC patient and successful management by adding ALK inhibitors: a case report.
BMC Cancer. 2016; 16:62 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Rebiopsy is highly recommended to identify the mechanism of acquired resistance to EGFR-TKIs in advanced lung cancer. Recent advances in multiplex genotyping based on circulating tumor DNA (ctDNA) provide a strong and non-invasive alternative for detection of the resistance mechanism.
CASE PRESENTATION: Here we report a multiple metastatic NSCLC patient who was detected to have pure EGFR 19 exon deletion (negative for EML4-ALK and ROS1 in both IHC-based and sequencing assay) in the primary lesion and responded to first-line and second-line EGFR-TKI treatments (erlotinib then HY-15772). At 8 months, most lesions remained well controlled except for the liver metastases which presented dramatic progression. Considering the high risk of bleeding in rebiopsy of hepatic lesions, we conducted a multiplex genomic profiling with ctDNA. Results reported coexistence of EGFR mutation and EML4-ALK gene translocation in plasma which heavily indicated that ALK was the primary reason for progression of the liver lesions. This deduction was supported by the repeated response to ALK inhibitors (crizotinib then AP26113) of the hepatic metastases.
CONCLUSIONS: This is the first report of the existence of ALK rearrangement in metastatic lesions in an EGFR mutated patient. It highlighted the feasibility and advantages of using ctDNA multiplex genotyping in identifying the heterogeneity across lesions and the resistance mechanism of targeted treatments.

Sunami K, Furuta K, Tsuta K, et al.
Multiplex Diagnosis of Oncogenic Fusion and MET Exon Skipping by Molecular Counting Using Formalin-Fixed Paraffin Embedded Lung Adenocarcinoma Tissues.
J Thorac Oncol. 2016; 11(2):203-12 [PubMed] Related Publications
INTRODUCTION: Fusions of the anaplastic lymphoma receptor tyrosine kinase gene (ALK), ret proto-oncogene (RET), ROS proto-oncogene 1, receptor tyrosine kinase gene (ROS1), B-Raf proto-oncogene, serine/threonine kinase gene (BRAF), and neuregulin 1 gene (NRG1) and intronic MMNG HOS Transforming gene (MET) mutations are druggable oncogene alterations in lung adenocarcinoma that cause expression of aberrant transcripts. Because these aberrant transcripts are both infrequent (incidence <5%) and mutually exclusive, multiplex assays are required to detect them in tumor samples.
METHODS: Aberrant transcripts of the six aforementioned oncogenes (36 transcripts in total) were examined in a molecular counting (MC) assay, which counts RNA molecules by simultaneous hybridization of several probes. Forty-one samples of surgically resected lung adenocarcinoma tissue found to express one of these aberrant oncogenic transcripts upon whole transcriptome sequencing (test cohort: n = 22) or reverse transcription polymerase chain reaction (validation cohort: n = 19) analyses were subjected to MC, after which biopsies were performed on tumor tissue samples.
RESULTS: Threshold values for the diagnosis of each of the 36 transcripts were determined in frozen and formalin-fixed paraffin-embedded samples from the test cohort. On the basis of these threshold values, the MC assay diagnosed expression of oncogenic transcripts in the validation cohort samples with 100% accuracy. The assay also accurately detected oncogenic fusions in bronchial lavage fluid and transbronchial biopsy samples.
CONCLUSIONS: The MC assay allows multiplex detection of oncogenic fusion and exon-skipped transcripts in tumor samples, including in formalin-fixed paraffin-embedded samples obtained in the clinic.

Zhang Q, Sun T, Kang P, et al.
Combined analysis of rearrangement of ALK, ROS1, somatic mutation of EGFR, KRAS, BRAF, PIK3CA, and mRNA expression of ERCC1, TYMS, RRM1, TUBB3, EGFR in patients with non-small cell lung cancer and their clinical significance.
Cancer Chemother Pharmacol. 2016; 77(3):583-93 [PubMed] Related Publications
PURPOSE: The assessment of single gene such as ERCC1, TYMS, RRM1, TUBB3, EGFR, KRAS, BRAF, PIK3CA, ALK, and ROS1 is now widely applied in therapeutic decisions of non-small cell lung cancer (NSCLC). The aim of our study was to concurrently analyze these genes and evaluate their clinical significance in patients with NSCLC.
METHODS: Rearrangement of ALK and ROS1 was analyzed in 120 patients using FISH assays. Somatic mutation of EGFR, KRAS, BRAF, PIK3CA and mRNA expression of ERCC1, TYMS, RRM1, TUBB3, EGFR were examined by liquidchip platform in 350 patients . Data on clinical features were obtained from medical records of 119 patients, and the follow-up was conducted in 106 patients who received platinum-based adjuvant chemotherapy.
RESULTS: We identified 5.0% ALK rearrangements, 1.7% ROS1 rearrangements, 36.6% EGFR mutations, 8.9% KRAS mutations, 0% BRAF mutations, and 4.0% PIK3CA mutations. Double or coexisting mutations were identified in 13 patients. Significant correlations were observed among EGFR, KRAS mutation, ERCC1, TYMS, RRM1, TUBB3, EGFR expression, and clinical features, especially histology (P < 0.05). Significant cross-correlations were observed in some pairs of genes (P < 0.05). Patients with low RRM1 expression had a better progression-free survival (PFS) (P < 0.05). Furthermore, EGFR-mutated patients with low RRM1 expression or patients with both ERCC1 and RRM1 low expression had a better PFS (P < 0.05).
CONCLUSION: Combined analysis of these commonly studied genes may promote the individual treatment in NSCLC. RRM1 may be a prognostic and predictive biomarker for PFS in patients with NSCLC who received platinum-based adjuvant chemotherapy, and combining EGFR mutation and RRM1 expression or combining ERCC1 and RRM1 expression can enhance prognostic and predictive power for PFS.

Forest F, Yvorel V, Karpathiou G, et al.
Histomolecular profiling of pleomorphic, spindle cell, and giant cell carcinoma of the lung for targeted therapies.
Hum Pathol. 2016; 49:99-106 [PubMed] Related Publications
In pleomorphic, spindle cell, and giant cell carcinoma (PSCGC) of the lung, we wondered if an integrated diagnosis including morphological and immunohistochemical features could be related to molecular status. We performed immunohistochemistry on 35 PSCGCs against TTF1, napsin A, p40, ALK, ROS1, and c-MET. Mutational status regarding EGFR, KRAS, BRAF, HER2, and PIK3CA genes was established. Of 18 PSCGCs with adenocarcinomatous or "undifferentiated" carcinoma differentiation, 8 were mutated for EGFR (n = 1), KRAS (n = 2), BRAF (n = 1), HER2 (n = 3), and PIK3CA (n = 1). No PSCGC (0/4) with only squamous cell or adenosquamous (0/2) differentiation was mutated. c-MET overexpression was only seen in PSCGC with adenocarcinomatous or undifferentiated component (n = 5) without squamous cell component. ROS1 and ALK were negative. The presence of a "targetable mutation" was correlated to the presence of morphological or immunohistochemical adenocarcinomatous differentiation (P = .0137). Integrated diagnosis of an adenocarcinomatous component in PSCGC could be associated with the presence of targetable gene mutation. Because only PSCGC with adenocarcinomatous or undifferentiated carcinoma harbors mutations, whereas PSCGC with only squamous or adenosquamous differentiation does not in our study, this might represent a prescreening for patients with PSCGC to be tested for molecular targets. Our results emphasize that careful morphological examination and the use of immunohistochemistry might be useful for the selection of PSCGC tested for a mutational target.

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