Therapeutic approach to treating patients with BRAF-mutant lung cancer: latest evidence and clinical implications

Integrated multi-omic analysis and experiment reveals the role of endoplasmic reticulum stress in lung adenocarcinoma

BACKGROUND

Lung cancer is a highly prevalent malignancy worldwide and is associated with high mortality rates. While the involvement of endoplasmic reticulum (ER) stress in the development of lung adenocarcinoma (LUAD) has been established, the underlying mechanism remains unclear.

METHODS

In this study, we utilized data from The Cancer Genome Atlas (TCGA) to identify differentially expressed endoplasmic reticulum stress-related genes (ERSRGs) between LUAD and normal tissues. We performed various bioinformatics analyses to investigate the biological functions of these ERSRGs. Using LASSO analysis and multivariate stepwise regression, we constructed a novel prognostic model based on the ERSRGs. We further validated the performance of the model using two independent datasets from the Gene Expression Omnibus (GEO). Additionally, we conducted functional enrichment analysis, immune checkpoint analysis, and immune infiltration analysis and drug sensitivity analysis of LUAD patients to explore the potential biological function of the model. Furthermore, we conducted a battery of experiments to verify the expression of ERSRGs in a real-world cohort.

RESULTS

We identified 106 ERSRGs associated with LUAD, which allowed us to classify LUAD patients into two subtypes based on gene expression differences. Using six prognostic genes (NUPR1, RHBDD2, VCP, BAK1, EIF2AK3, MBTPS2), we constructed a prognostic model that exhibited excellent predictive performance in the training dataset and was successfully validated in two independent external datasets. The risk score derived from this model emerged as an independent prognostic factor for LUAD. Confirmation of the linkage between this risk model and immune infiltration was affirmed through the utilization of Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The q-PCR results verified significant differences in the expression of prognostic genes between cancer and paracancer tissues. Notably, the protein expression of NUPR1, as determined by immunohistochemistry (IHC), exhibited an opposite pattern compared to the mRNA expression patterns.

CONCLUSION

This study establishes a novel prognostic model for LUAD based on six ER stress-related genes, facilitating the prediction of LUAD prognosis. Additionally, NUPR1 was identified as a potential regulator of stress in LUAD.

A Novel Predictive Model Incorporating Ferroptosis-Related Gene Signatures for Overall Survival in Patients with Lung Adenocarcinoma

BACKGROUND Lung adenocarcinoma (LUAD) is the predominant histological type of lung cancer with high morbidity and mortality. Ferroptosis is regarded as a new pattern of programmed cell death concerned with the progression of lung cancer characterized by lipid peroxidation. Nevertheless, the prognostic role of ferroptosis-related genes for LUAD warrant to be explored. MATERIAL AND METHODS RNA sequencing and relevant clinical patient data were obtained from public-access databanks. A prognostic model was constructed through the LASSO Cox regression in the cancer genome atlas cohort. The diagnostic value of the prognostic model was further evaluated in the gene expression omnibus cohort. RESULTS Most of the ferroptosis-related genes (69.9%) were differentially expressed between tumor and adjacent non-cancerous tissues. 43 differentially expressed genes showed a close association with the prognosis of LUAD patients (adjusted p-value <0.05). An 18-gene signature was built and applied to assign patients into high vs low-risk groups. Compared with the high-risk group, patients defined as the low-risk group suffered significantly prolonged OS. Both uni- and multivariate analyses demonstrated that the signature-based score served as a crucial role in influencing the OS of LUAD patients (hazard ratio >1, p<0.001). The immunity-related signaling pathway was enriched in the functional analysis and the infiltration of the immune cells showed a great difference between groups. CONCLUSIONS The predictive model could be applied for prognostic prediction for LUAD. Targeting ferroptosis could be a possible curative strategy against LUAD, and immunomodulation may be one of the potential mechanisms.

Metastatic BRAF V600E-Mutated Adenocarcinoma of the Lung Presenting as Extreme Neutrophilia and Eosinophilia

Hematologic paraneoplastic syndromes with extreme neutrophilia and eosinophilia are very rarely associated with adenocarcinoma of the lung. We describe a case of a 57-year-old female who presented with neutrophil- and eosinophil-predominant hyperleukocytosis and hypoxic respiratory insufficiency. Bone marrow biopsy confirmed metastatic adenocarcinoma, similar to the biopsy-proven adenocarcinoma of the lung. She was administered one dose of cytotoxic chemotherapy with carboplatin and pemetrexed and started on leukoreductive therapy with hydroxyurea. Molecular testing revealed a BRAF V600E mutation and she was started on dabrafenib and trametinib with significant clinical improvement. This is the first reported case of metastatic BRAF V600E mutated non-small cell lung cancer presenting with extreme neutrophilia and eosinophilia treated with a combination BRAF and mitogen-activated extracellular kinase (MEK) inhibitor.

Short report: Performance evaluation of the Idylla™ KRAS and EGFR mutation tests on paraffin-embedded cytological NSCLC samples

BACKGROUND

Quick and reliable testing of EGFR and KRAS is needed in non-small cell lung cancer (NSCLC) to ensure optimal decision-making for targeted therapy. The Idylla™ platform was designed for Formalin-Fixed Paraffin-Embedded (FFPE) tissue sections but recently several studies were published that evaluated its potential for cytological specimens. This study aimed to validate the Idylla™ platform for the detection of EGFR/KRAS mutations in cytological NSCLC samples prepared as cytoblocks using AGAR and paraffin embedding.

MATERIAL AND METHODS

The KRAS Idylla™ test were performed on 11 specimens with a known KRAS mutation. The EGFR Idylla™ test was performed on 18 specimens with a known primary EGFR mutation and 7 specimens with a primary EGFR-EGFR T790M resistance mutation combination.

RESULTS

Concordant KRAS and primary EGFR mutations were detected for both KRAS and primary EGFR mutations. Samples with a total CQ value of < 26 could be considered negative. Samples with a total CQ value of > 26 could not be assessed (probability of false-negative). In specimens with a primary EGFR-EGFR T790M resistance mutation combination, 5/7 cases were not concordant.

CONCLUSION

Our results confirm the conclusion of recent reports that the Idylla™EGFR assay is not suitable in a resistance to EGFR TKI setting, also not in our cytological NSCLC samples prepared as cytoblocks using AGAR and paraffin embedding. KRAS and primary EGFR mutations were detected using the Idylla™ assays in virtually all cytological NSCLC samples. This analysis was rapid and time-saving compared to other mutation detection assays and may be useful if the amount of material is insufficient to perform a full set of molecular tests.

MiR-338-3p improved lung adenocarcinoma by AKAP12 suppression

INTRODUCTION

This study aimed to explore the biological functions of AKAP12 in lung adenocarcinoma and investigate the interaction between AKAP12 and miR-338-3p.

MATERIAL AND METHODS

Sixty-one differentially expressed genes in lung adenocarcinoma and adjacent normal tissues were first analyzed by TCGA. Immunohistochemistry and quantitative reverse transcription PCR (qRT-PCR) were further utilized to confirm aberrant AKAP12 expression in tumor tissues. The influences of AKAP12 on proliferation, invasion and migration, and apoptosis of lung adenocarcinoma were investigated by clone formation assay and MTT assay, transwell assay, and flow cytometry analysis respectively. TargetScan and miRanda databases predicted the binding sites of miRNAs on AKAP12 3'-UTR and structure changes were validated by RNA folding form. The target relationship between miR-338-3p and AKAP12 was confirmed by the dual-luciferase reporter system. Disease-free survival (DFS) and overall survival (OS) curves were generated with Kaplan-Meier plotter according to the TCGA data and the correlation among AKAP12 expression, miR-338-3p expression and prognosis was also analyzed.

RESULTS

AKAP12 was upregulated in lung adenocarcinoma tissues and cells (all p < 0.01), and negatively correlated with prognosis outcomes of patients (both p < 0.05). High expression of AKAP12 promoted proliferation, invasion and migration of cancer cells, and inhibited cell apoptosis (all p < 0.05). MiR-338-3p could directly bind to the 3'-UTR of AKAP12 and showed most significant suppression on AKAP12 expression among four predicted miRNAs (all p < 0.01). Additionally, miR-338-3p could suppress AKAP12 in lung adenocarcinoma, improving prognosis (all p < 0.05).

CONCLUSIONS

AKAP12 acts as a tumor promoter in lung adenocarcinoma development. Upregulation of MiR-338-3p could suppress AKAP12 expression in lung cancer cells and contribute to a better prognosis.

BRAF mutations in KIT/PDGFRA positive gastrointestinal stromal tumours (GISTs): Is their frequency underestimated?

BRAF V600E mutations in GISTs are considered to be one of the mutational events in KIT/PDGFRA negative or positive GISTs, respectively. BRAF mutated GISTs usually do not respond to imatinib treatment, even more GISTs with imatinib sensitive KIT mutation. However, they are almost phenotypically and morphologically identical with KIT/PDGFRA positive GISTs. In general, due to the small number of BRAF mutations in GIST and because of the rarity of concomitant BRAF/KIT or BRAF/PDGFRA mutations, their frequency may be depreciated. The aim of this study was BRAF mutation detection in KIT/PDGFRA positive GISTs and their verification by other molecular methods. We applied the sensitive droplet digital PCR on 35 randomly selected KIT/PDGFRA positive GISTs to detect V600E mutations. We have established two criteria for the evaluation of samples: false positive rate (FPR) based on the negative controls; Limit of Detection (LoD) based on the serial dilution of positive control from RKO cell line harboring heterozygous V600E mutation in constant wild-type DNA background. Results from ddPCR were verified by other molecular methods: allele-specific PCR, dideoxysequencing, competitive allele-specific TaqMan PCR (castPCR). FPR was determined as 5 (∼4.4) positive droplets, and LoD was assessed to 3.4293 copies/μL what is the method sensitivity of 0.0162 %. We identified eight KIT/PDGFRA positive patients with concomitant V600E mutation. The five of them were in coexistence with KIT mutation and three with PDGFRA mutation. We also included the liver metastasis, but data from primary tumour were not available. We achieved the very high sensitivity of the ddPCR method for detecting BRAF mutation in GISTs to have importance from the point of view of therapy.

Pseudomyxoma Peritonei Originating from Transverse Colon Mucinous Adenocarcinoma: A Case Report and Literature Review

Background

Pseudomyxoma peritonei (PMP) is a rare neoplasm involving the peritoneum. Most PMPs are low-grade appendicular mucinous neoplasms (LAMNs). There have been no reports of PMP originating from a transverse colonic mucinous adenocarcinoma and causing metastatic mucinous adenocarcinoma. Case Presentation. We report a 46-year-old woman who presented with a right abdominal mass of more than 4-month duration. Transverse colonic mucinous adenocarcinoma, PMP, and ovarian metastatic mucinous adenocarcinoma were diagnosed. The patient's diet was normal, and she had no abdominal pain or bloating. The abdomen mass increased in the month before treatment. After chemotherapy, the transverse colon mass and ovarian giant cyst were resected and about 2000 mL of gelatinous tumor tissue was removed. Postoperative histology confirmed PMP from the transverse colonic mucinous adenocarcinoma, ovarian metastatic mucinous adenocarcinoma, and mesocolon metastatic cancer. Multiple lung metastases appeared 8 months after surgery. The patient died 29 months after surgery because of an inability to eat and poor nutrition. A systematic literature review of the management and outcome of all known similar cases is also presented.

Conclusions

This is the first report of PMP originating from a transverse colonic mucinous adenocarcinoma. It was diagnosed during resective surgery, involved ovarian metastasis, and survival was short. We did an extensive literature review in order to describe the clinical characteristics, histopathological findings, genetic profile, and potential treatments of PMP caused by nonappendiceal mucinous adenocarcinoma.

PNO1, which is negatively regulated by miR-340-5p, promotes lung adenocarcinoma progression through Notch signaling pathway

Many studies have shown that the hyperactivation of ribosome biogenesis plays essential roles in the initiation and progression of cancers. As a ribosome assembly factor, PNO1 plays an important role in ribosome biogenesis. However, little is known about the expression and function of PNO1 in human tumors. In our present study, we aimed to explore the functional roles and the underlying molecular mechanisms of PNO1 in human lung adenocarcinoma (LUAD). Both bioinformatics databases and tumor tissues demonstrated that the expression of PNO1 in LUAD tissues was higher than that in adjacent tissues and predicted poor survival in LUAD patients. In vitro and in vivo assays suggested that downregulation of PNO1 expression suppressed LUAD cell proliferation and invasion. Further studies found that miR-340-5p depressed PNO1 expression via direct binding to the 3′ untranslated region (UTR) of PNO1. PNO1 expression was negatively correlated with miR-340-5p expression in LUAD cells and tissue samples. Moreover, upregulation or downregulation of miR-340-5p expression reversed the effects of PNO1 inhibition and overexpression, respectively. Meanwhile, downregulation of PNO1 inhibited Notch signaling pathway which modulated epithelial mesenchymal transition (EMT). These results indicate that PNO1, negatively regulated by miR-340-5p, played an important role in LUAD progression via Notch signaling pathway. The miR-340-5p/PNO1/Notch axis might be a potential target for individualized and precise treatment of LUAD patients in the future.

Survival prediction model for non-small cell lung cancer based on somatic mutations

BACKGROUND

The 5-year survival rate of non-small cell lung cancer (NSCLC) is only 15%. Screening some combined gene mutations could predict the survival of NSCLC patients and also provide new ideas for the diagnosis and treatment of NSCLC. The present study aimed to identify signature mutations for survival prediction of NSCLC.

METHODS

Clinical and gene mutation information for 949 NSCLC patients was downloaded from TCGA. High frequency mutation and common mutation genes were analyzed based on 1000 cancer related genes. The LASSO-COX model was used to screen gene mutation points and analyze their survival, and then a survival prediction model was established. Fifty NSCLC patients were collected and 1000 targeted genes were enriched by targeted next generation sequencing. The results were used to verify the combination of common mutation genes and the function of the survival model, and then to clarify their clinical significance.

RESULTS

Ten variables were screened out after LASSO-COX analysis, including age, tumor stage, EGFR c.[2,573 T>G], PIK3CA c.[1624G>A], TP53 c.[375G>T], TP53 c.[527G>T], TP53 c.[733G>T], TP53 c.[734G>T], TP53 c.[743G>T], NFE2L2 c.[100C>G]. Except for TP53 c.[743G>T] and NFE2L2 c.[100C>G], the residual six hot spot mutations of EGFR, PIK3CA and TP53 could be regarded as a signature mutations for forecasting the survival time of NSCLC.

CONCLUSIONS

The combination of six hot spot mutations of EGFR, PIK3CA and TP53 is expected to be used for predicting the survival time of NSCLC.

Treatment of oncogene-driven non-small cell lung cancer

PURPOSE OF REVIEW

With the development of targeted therapies, the treatment strategy of patients with advanced or metastatic non-small cell lung cancer (NSCLC) has changed tremendously. In this review, we focus on the different aspects of the treatment of oncogene-driven NSCLC.

RECENT FINDINGS

Patients with an EGFR or ALK alteration show a better clinical outcome with tyrosine kinase inhibitor (TKI) treatment compared to chemotherapy.Patients with a ROS1 rearrangement or a BRAF V600E mutation show favorable clinical outcome with TKI treatment compared to chemotherapy, although randomized trials are not available.Patients on TKIs will eventually develop disease progression because of acquired resistance.The treatment with immunotherapy in EGFR and ALK-positive NSCLC patients did not improve overall survival over that of chemotherapy.Blood-based genetic analysis provides the opportunity to noninvasively screen patients for the presence of oncogenic drivers and to monitor resistance during TKI treatment.

SUMMARY

Targeted molecular therapies are now standard of care for patients with oncogene-driven NSCLC with a good clinical benefit and minimal toxicity. The role of immunotherapy in patients with molecular alterations is still unclear. Blood-based genotyping has gained interest in the diagnostic and resistance monitoring setting for patients with NSCLC.

Concurrent inhibition of ErbB family and MEK/ERK kinases to suppress non-small cell lung cancer proliferation

Lung cancer ranks as the most common cancer and leading cause of cancer-related deaths worldwide. Of all lung cancer types, non-small cell lung cancer (NSCLC) accounts for 85 percent of all cases. The high mortality of NSCLC occurs mainly because of poor prognosis in patients with recurrent and metastatic cancer. Cisplatin-containing chemotherapy is the first option to treat recurrent and metastatic NSCLC. Additionally, targeted therapy plays an important role to prolong life in patients. Currently, EGFR inhibitors are the most important targeted anti-cancer drugs for patients with EGFR mutations in the clinical setting. Another important kinase inhibitor for targeted therapy is the MEK inhibitor, Trametinib, which is often used for patients with BRAF mutation or MEK/ERK activation in the tumors. In this study, we determined whether a combination of the pan-ErbB kinase inhibitor, Afatinib, and MEK inhibitor, Trametinib, could more effectively inhibit NSCLC cell proliferation when compared to either single treatment. We found that Afatinib inhibited phosphorylation of EGFR, HER2, HER3, and HER4, as well as Akt, whereas it elevated ERK phosphorylation. Conversely, Trametinib treatment led to ERK inhibition, but induced Akt phosphorylation. However, the combination of Afatinib and Trametinib inhibited all of the above-mentioned signaling pathways and synergistically suppressed cell proliferation. Our data indicate that co-targeting of ErbB family and MEK/ERK pathways through a combination of Afatinib and Trametinib could be a potential effective strategy to treat NSCLC.

FOX-A1 contributes to acquisition of chemoresistance in human lung adenocarcinoma via transactivation of SOX5

Background

Chemoresistance is a major obstacle for the effective treatment of lung adenocarcinoma (LAD). Forkhead box (FOX) proteins have been demonstrated to play critical roles in promoting epithelial-mesenchymal transition (EMT) and chemoresistance. However, whether FOX proteins contribute to the acquisition of EMT and chemoresistance in LAD remains largely unknown.

Methods

FOX-A1 expression was measured in LAD cells and tissues by qRT-PCR. The expression levels of EMT markers were detected by western blotting and immunofluorescence assay. The interaction between Sex determining region Y-box protein 5 (SOX5) and FOX-A1 was validated by chromatin immunoprecipitation sequence (ChIP-seq) and Chromatin immunoprecipitation (ChIP) assay. Kaplan-Meier analysis and multivariate Cox regression analysis were performed to analyze the significance of FOX-A1 and SOX5 expression in the prognosis of LAD patients.

Findings

FOX-A1 was upregulated in docetaxel-resistant LAD cells. High FOX-A1 expression was closely associated with a worse prognosis. Upregulation of FOX-A1 in LAD samples indicated short progression-free survival (PFS) and overall survival (OS). SOX5 is a new and direct target of FOX-A1 and was positively regulated by FOX-A1 in LAD cell lines. Knockdown of FOX-A1 or SOX5 reversed the chemoresistance of docetaxel-resistant LAD cells by suppressing cell proliferation, migration and EMT progress.

Interpretation

These data elucidated an original FOX-A1/SOX5 pathway that represents a promising therapeutic target for chemosensitizing LAD and provides predictive biomarkers for evaluating the efficacy of chemotherapies.

Current and Future Molecular Testing in NSCLC, What Can We Expect from New Sequencing Technologies?

Recent changes in lung cancer care, including new approvals in first line and the introduction of high-throughput molecular technologies in routine testing led us to question ourselves on how deeper molecular testing may be helpful for the optimal use of targeted drugs. In this article, we review recent results in the scope of personalized medicine in lung cancer. We discuss biomarkers that have a therapeutic predictive value in lung cancer with a focus on recent changes and on the clinical value of large scale sequencing strategies. We review the use of second- and third-generation EGFR and ALK inhibitors with a focus on secondary resistance alterations. We discuss anti-BRAF and anti-MEK combo, emerging biomarkers as NRG1 and NTRKs fusions and immunotherapy. Finally, we discuss the different technical issues of comprehensive molecular profiling and show how large screenings might refine the prediction value of individual markers. Based on a review of recent publications (2012⁻2018), we address promising approaches for the treatment of patients with lung cancers and the technical challenges associated with the identification of new predictive markers.

Comparison of tumor related signaling pathways with known compounds to determine potential agents for lung adenocarcinoma

Background

This study compared tumor‐related signaling pathways with known compounds to determine potential agents for lung adenocarcinoma (LUAD) treatment.

Methods

Kyoto Encyclopedia of Genes and Genomes signaling pathway analyses were performed based on LUAD differentially expressed genes from The Cancer Genome Atlas (TCGA) project and genotype‐tissue expression controls. These results were compared to various known compounds using the Connectivity Mapping dataset. The clinical significance of the hub genes identified by overlapping pathway enrichment analysis was further investigated using data mining from multiple sources. A drug‐pathway network for LUAD was constructed, and molecular docking was carried out.

Results

After the integration of 57 LUAD‐related pathways and 35 pathways affected by small molecules, five overlapping pathways were revealed. Among these five pathways, the p53 signaling pathway was the most significant, with CCNB1, CCNB2, CDK1, CDKN2A, and CHEK1 being identified as hub genes. The p53 signaling pathway is implicated as a risk factor for LUAD tumorigenesis and survival. A total of 88 molecules significantly inhibiting the five LUAD‐related oncogenic pathways were involved in the LUAD drug‐pathway network. Daunorubicin, mycophenolic acid, and pyrvinium could potentially target the hub gene CHEK1 directly.

Conclusion

Our study highlights the critical pathways that should be targeted in the search for potential LUAD treatments, most importantly, the p53 signaling pathway. Some compounds, such as ciclopirox and AG‐028671, may have potential roles for LUAD treatment but require further experimental verification.

BRAF and EGFR inhibitors synergize to increase cytotoxic effects and decrease stem cell capacities in BRAF(V600E)-mutant colorectal cancer cells

Mutations in the oncogene BRAF(V600E) are found in ~10% of colorectal cancers (CRCs) and are associated with poor prognosis. However, BRAF(V600E) has a limited response to the small-molecule drug, vemurafenib, a BRAF inhibitor, and BRAF inhibition is thought to cause a feedback activation of EGFR signaling that supports continued proliferation. In this study, we explored the effect of combined use of dabrafenib, a BRAF inhibitor, and cetuximab, an EGFR inhibitor, on BRAF(V600E)-mutant CRC stem cells and its possible mechanisms. Through cell viability analysis, flow cytometry, sphere forming, and western blot analysis, we found that the dabrafenib can synergize with cetuximab to reduce cell viability, induce enhanced apoptotic rates and cell cycle arrest in BRAF(V600E)-mutant HT-29 cells and inhibits stem cell capacities. Further, western blot analysis revealed that PTEN/Src/c-Myc pathway is possibly involved in the synergism between dabrafenib and cetuximab. Overall, our study shows that the combination of dabrafenib and cetuximab results in increased antitumor activity and decreased stem cell capacities in BRAF(V600E)-mutant CRC cells.

Systemic therapy for brain metastases

Central nervous system metastases cause grave morbidity in patients with advanced malignancies. Lung cancer, breast cancer, and melanoma are the three most common causes of brain metastases. Although the exact incidence of brain metastases is unclear, there appears to be an increasing incidence which has been attributed to longer survival, better control of systemic disease, and better imaging modalities. Until recently surgical resection of solitary or symptomatic brain metastases, and radiation therapy (either whole-brain radiation therapy or stereotactic radiation) were the mainstay of treatment for patients with brain metastases. The majority of traditional chemotherapies have shown limited activity in the central nervous system, which has been attributed to the blood-brain barrier and the molecular structure of the used agents. The discovery of driver mutations and drugs targeting these mutations has changed the treatment landscape. Several of these targeted small-molecule tyrosine kinase inhibitors do cross the blood-brain barrier and/or have shown activity in the central nervous system. Another major advance in the care of brain metastases has been the advent of new immunotherapeutic agents, for which initial studies have shown intracranial activity. In this chapter, we will review the unique challenges in the treatment of brain metastases. The pertinent clinical studies of chemotherapy in brain metastases will be discussed. The currently reported clinical trials and evidence for use of targeted therapies and immunotherapeutic agents will be emphasized.

Current Landscape of Targeted Therapy in Lung Cancer

Lung cancer is the leading cause of cancer mortality worldwide. Comprehensive genomic profiling of lung cancers revealed their genetic heterogeneity and complexity and identified numerous targetable oncogenic driver alterations. These molecular profiling efforts have made it possible to exploit the potential of molecularly targeted therapies. Selection of patients for targeted therapies is becoming biomarker-driven, where the oncogenic drivers in patient tumors are first identified, and subsequently patients bearing drug-sensitizing genetic aberrations are matched to the appropriate targeted therapy. Success of this design of clinical trials and practice was first demonstrated in EGFR inhibitor trials in lung cancer and has since been incorporated into subsequent targeted therapy trials including ALK-, ROS1-, and BRAF V600E-targeted therapies. In this review we discuss the current landscape of clinically approved and other promising molecularly targeted approaches for the treatment of lung cancers, the challenges with these approaches, and the strategies that could be deployed to overcome these challenges.

Emerging uses of biomarkers in lung cancer management: molecular mechanisms of resistance

Management of patients with advanced non-small cell lung cancer (NSCLC) has recently been transformed by molecularly targeted and immunotherapeutic agents. In patients with EGFR/ALK/ROS mutated NSCLC, first line molecular therapy is the standard of care. Moreover, immune checkpoint inhibitors are revolutionary treatment options for advanced NSCLC and are now the standard of care in front-line or later line settings. Both classes of agents have led to improved patient outcomes, however, primary resistance and development of acquired resistance to both targeted and immunotherapeutic agents is commonly observed, limiting the use of these agents in clinical settings. In this review, we will discuss the most recent advances in understanding the mechanisms of primary and acquired resistance, progress in the spectrum of assays detecting causative molecular events and the development of new generations of inhibitors to overcome acquired resistance.

BRAF V600Q-mutated lung adenocarcinoma with duodenal metastasis and extreme leukocytosis

Driver mutations in patients with non-small cell lung cancer (NSCLC) can lead to distinct behaviors and patterns of metastasis. Mutations in the proto-oncogene B-raf (BRAF) occur in approximately 3% of NSCLC cases. In the literature, reports of patients with lung adenocarcinomas metastasizing to the duodenum are rare, and most of the only 21 cases reported were from before the advent of next-generation sequencing. We present here a case involving a 57-year-old female who had a lytic lesion in her lesser trochanter. Biopsy showed metastatic adenocarcinoma of lung origin. Chest X-ray showed a large left upper lobe mass. Next-generation sequencing analysis confirmed the presence of BRAF V600Q mutation. The patient presented with persistent anemia and melena. Esophagogastroduodenoscopy confirmed the presence of duodenal metastasis. She also had suspected paraneoplastic leukemoid reaction. To our knowledge, this is only the second well-documented case of gastrointestinal metastasis from BRAF-mutated lung cancer.

Biology and clinical significance of circulating tumor cell subpopulations in lung cancer

By identifying and tracking genetic changes in primary tumors and metastases, patients can be stratified for the most efficient therapeutic regimen by screening for known biomarkers. However, retrieving tissues biopsies is not always feasible due to tumor location or risk to patient. Therefore, a liquid biopsies approach offers an appealing solution to an otherwise invasive procedure. The rapid growth of the liquid biopsy field has been aided by improvements in the sensitivity and specificity of enrichment assays for isolating circulating tumor cells (CTCs) from normal surrounding blood cells. Furthermore, the identification and molecular characterization of CTCs has been shown in numerous studies to be of diagnostic and prognostic relevance in breast, prostate and colon cancer patients. Despite these advancements, and the highly metastatic nature of lung cancer, it remains a challenge to detect CTCs in advanced non-small cell lung cancer (NSCLC). It may be that loss of epithelial features, in favor of a mesenchymal phenotype, and the highly heterogeneous nature of NSCLC CTCs contribute to their evasion from current detection methods. By identifying a broader spectrum of biomarkers that could better differentiate the various NSCLC CTCs subpopulations, it may be possible to not only improve detection rates but also to shed light on which CTC clones are likely to drive metastatic initiation. Here we review the biology of CTCs and describe a number of proteins and genetic targets which could potentially be utilized for the dissemination of heterogenic subpopulations of CTCs in NSCLC.

Targeted Lung Cancer Treatments and Eye Metastasis

Lung cancer remains the leading cause of death due to cancer. We do not have effective tools for the early detection of lung cancer, so patients are usually diagnosed at an advanced stage. However, novel therapies based on molecular pathways (such as those involving the epidermal growth factor receptor, anaplastic lymphoma kinase, serine/threonine-protein kinase B-Raf, proto-oncogene tyrosine-protein kinase ROS, c-Met proto-oncogene protein, and RET proto-oncogene protein) are now commonly used in the treatment of lung cancer. In particular, these therapies are considered as first-line treatments for non-small-cell lung cancer. This manuscript outlines previous research on these targeted treatments, focusing on whether they are effective against eye metastasis.