A Novel Cytochrome P450 2E1 Inhibitor Q11 Is Effective on Lung Cancer via Regulation of the Inflammatory Microenvironment

Lung cancer is the leading cause of death among all cancers. A persistent chronic inflammatory microenvironment is highly correlated with lung cancer. However, there are no anti-inflammatory agents effective against lung cancer. Cytochrome P450 2E1 (CYP2E1) plays an important role in the inflammatory response. Here, it is found that CYP2E1 is significantly higher in the peritumoral tissue of non-small cell lung cancer (NSCLC) patients and lung tumor growth is significantly impeded in Cyp2e1-/- mice. The novel CYP2E1 inhibitor Q11, 1-(4-methyl-5-thialzolyl) ethenone, is effective in the treatment of lung cancer in mice, which can inhibit cancer cells by changing macrophage polarization rather than directly act on the cancer cells. It is also clarify that the benefit of Q11 may associated with the IL-6/STAT3 and MAPK/ERK pathways. The data demonstrate that CYP2E1 may be a novel inflammatory target and that Q11 is effective on lung cancer by regulation of the inflammatory microenvironment. These findings provide a molecular basis for targeting CYP2E1 and illustrate the potential druggability of the CYP2E1 inhibitor Q11.

p38 Mediates Resistance to FGFR Inhibition in Non-Small Cell Lung Cancer

FGFR signalling is one of the most prominent pathways involved in cell growth and development as well as cancer progression. FGFR1 amplification occurs in approximately 20% of all squamous cell lung carcinomas (SCC), a predominant subtype of non-small cell lung carcinoma (NSCLC), indicating FGFR as a potential target for the new anti-cancer treatment. However, acquired resistance to this type of therapies remains a serious clinical challenge. Here, we investigated the NSCLC cell lines response and potential mechanism of acquired resistance to novel selective FGFR inhibitor CPL304110. We found that despite significant genomic differences between CPL304110-sensitive cell lines, their resistant variants were characterised by upregulated p38 expression/phosphorylation, as well as enhanced expression of genes involved in MAPK signalling. We revealed that p38 inhibition restored sensitivity to CPL304110 in these cells. Moreover, the overexpression of this kinase in parental cells led to impaired response to FGFR inhibition, thus confirming that p38 MAPK is a driver of resistance to a novel FGFR inhibitor. Taken together, our results provide an insight into the potential direction for NSCLC targeted therapy.

Overexpression of Human Aspartyl (Asparaginyl) β-hydroxylase in NSCLC: Its Diagnostic Value by Means of Exosomes of Bronchoalveolar Lavage

The human aspartyl β-hydroxylase (ASPH) is overexpressed in tumor tissues. Bronchoalveolar lavage (BAL) is a diagnostic procedure for infections and malignancies. The aim of this study was to investigate whether tumor exosomes carrying ASPH gene marker were present in bronchoalveolar fluid of patients with non-small cell lung cancer (NSCLC). A tissue microarray analysis was applied to explore the expression of ASPH in different histologic NSCLC. The human NSCLC cell lines and normal bronchial cell lines were used to study exosomal ASPH exprerssion. A total of 27 NSCLC, 21 benign tumor, and 15 healthy controls underwent BAL. Immunohistochemistry was performed to study the ASPH expression in malignant and normal lung tissues. The expression characteristics of ASPH in different NSCLC and normal bronchial cells and pneumocytes were confirmed by cell blocks. A reverse transcription-quantitative polymerase chain reaction was carried out to study the levels of exosomal ASPH expression. Immunohistochemical staining of tissue microarray demonstrated that overexpression of ASPH was found in NSCLC tissues including adenocarcinoma, large cell carcinoma, and squamous cell carcinoma, but absent in adjacent normal tissues. All NSCLC specimens exhibited high levels of ASPH immunoreactivity, while nonmalignant and normal lung tissues exhibited a very low level of expression. Overexpression of ASPH was found in exosomes from NSCLC cell lines but absent from the normal bronchial cell line NL-20. ASPH level from BAL exosomes was significantly increased in NSCLC patients compared with that from nonmalignant or health group. Our method of isolation of BAL exosomes was easily performed in the clinical laboratory. BAL exosomal ASPH can be a potential biomarker for NSCLC diagnosis.

USP52 inhibits cell proliferation by stabilizing PTEN protein in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common subtype of lung cancer. Ubiquitination is closely related to the development of lung cancer. However, the biological importance of newly discovered ubiquitin-specific peptidase (USP) 52 (USP52) in NSCLC remained unclear. Here, our findings identify USP52 as a novel tumor suppressor of NSCLC, the low expression of USP52 predicts a poor prognosis for NSCLC patients. The present study demonstrates that USP52 inhibits cancer cell proliferation through down-regulation of cyclin D1 (CCND1) as well as AKT/mTOR signaling pathway inhibition. Meanwhile, USP25 also suppresses NSCLC progression via enhancing phosphatase and tensin homolog (PTEN) stability in cancer cells, which further indicates the significance/importance of USP52 in NSCLC suppression.

RNF8-mediated regulation of Akt promotes lung cancer cell survival and resistance to DNA damage

Despite the tremendous success of targeted and conventional therapies for lung cancer, therapeutic resistance is a common and major clinical challenge. RNF8 is a ubiquitin E3 ligase that plays essential roles in the DNA damage response; however, its role in the pathogenesis of lung cancer is unclear. Here, we report that RNF8 is overexpressed in lung cancer and positively correlates with the expression of p-Akt and poor survival of patients with non-small-cell lung cancer. In addition, we identify RNF8 as the E3 ligase for regulating the activation of Akt by K63-linked ubiquitination under physiological and genotoxic conditions, which leads to lung cancer cell proliferation and resistance to chemotherapy. Together, our study suggests that RNF8 could be a very promising target in precision medicine for lung cancer.

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.

The requirement of mitochondrial RNA polymerase for non-small cell lung cancer cell growth

POLRMT (RNA polymerase mitochondrial) is responsible for the transcription of mitochondrial genome encoding key components of oxidative phosphorylation. This process is important for cancer cell growth. The current study tested expression and potential functions of POLRMT in non-small cell lung cancer (NSCLC). TCGA cohorts and the results from the local lung cancer tissues showed that POLRMT is overexpressed in human lung cancer tissues. In both primary human NSCLC cells and A549 cells, POLRMT silencing (by targeted lentiviral shRNAs) or knockout (through CRSIPR/Cas9 gene editing method) potently inhibited cell viability, proliferation, migration, and invasion, and induced apoptosis activation. On the contrast, ectopic overexpression of POLRMT using a lentiviral construct accelerated cell proliferation and migration in NSCLC cells. The mtDNA contents, mRNA levels of mitochondrial transcripts, and subunits of respiratory chain complexes, as well as S6 phosphorylation, were decreased in POLRMT-silenced or -knockout NSCLC cells, but increased after ectopic POLRMT overexpression. In vivo, intratumoral injection of POLRMT shRNA adeno-associated virus (AAV) potently inhibited NSCLC xenograft growth in severe combined immune deficiency mice. The mtDNA contents, mRNA levels of mitochondria respiratory chain complex subunits, and S6 phosphorylation were decreased in POLRMT shRNA AAV-injected NSCLC xenograft tissues. These results show that POLRMT is a novel and important oncogene required for NSCLC cell growth in vitro and in vivo.

Circ_0006988 promotes the proliferation, metastasis and angiogenesis of non-small cell lung cancer cells by modulating miR-491-5p/MAP3K3 axis

Circular RNAs (circRNAs) are related to the progression of non-small cell lung cancer (NSCLC). However, the roles and mechanism of circ_0006988 are largely unknown. The levels of circ_0006988, Low-Density Lipoprotein Receptor Class A Domain Containing 3 (LDLRAD3), microRNA-491-5p (miR-491-5p), Mitogen-Activated Protein Kinase Kinase Kinase 3 (MAP3K3) were measured using quantitative real-time polymerase-chain reaction (qRT-PCR) and western blot assay. The characteristic of circ_0006988 was analyzed by RNase R assay and Actinomycin D assay. Functional analyses were processed by Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, colony formation assay, flow cytometry analysis, transwell assay, wound-healing assay and tube formation assay. The interactions between circ_0006988 and miR-491-5p as well as miR-491-5p and MAP3K3 were analyzed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Murine xenograft model assay was processed to verify the function of circ_0006988 in vivo. Immunohistochemistry (IHC) assay was conducted to examine the level of Ki67. Circ_0006988 abundance was increased in NSCLC tissues and cells. Circ_0006988 silencing restrained NSCLC cell proliferation, migration, invasion and angiogenesis, and induced apoptosis. Circ_0006988 sponged miR-491-5p, which directly targeted MAP3K3. MiR-491-5p overexpression repressed NSCLC cell malignant behaviors. MiR-491-5p downregulation or MAP3K3 overexpression reversed the effect of circ_0006988 silencing on NSCLC cell progression. In addition, circ_0006988 knockdown reduced xenograft tumor growth. ssCirc_0006988 contributed to the development of NSCLC by miR-491-5p/MAP3K3 axis.

Repression of the AURKA-CXCL5 axis induces autophagic cell death and promotes radiosensitivity in non-small-cell lung cancer

Aurora kinase A (AURKA) regulates apoptosis and autophagy in various diseases and has shown promising clinical effects. Nevertheless, the complex regulatory mechanism of AURKA and autophagy in non-small-cell lung cancer (NSCLC) radiosensitivity remains to be elucidated. Here, we showed that AURKA was upregulated in NSCLC cell lines and tissues and that AURKA overexpression was significantly related to a poor prognosis, tumor stage and lymph node metastasis in NSCLC. Interestingly, AURKA expression was significantly increased after 8Gy radiotherapy. Silencing of AURKA enhanced radiosensitivity and impaired migration and invasion in vivo and in vitro. Mechanistically, we determined that CXCL5, a member of the chemokine family, was a key downstream effector of AURKA, and the phenotype induced by AURKA silencing was partly due to CXCL5 inhibition. We further demonstrated that the AURKA-CXCL5 axis played an essential role in NSCLC autophagy and that the activation of cytotoxic autophagy attenuated the malignant biological behavior of NSCLC cells mediated by AURKA-CXCL5. In general, we revealed the role of the AURKA-CXCL5 axis and autophagy in regulating the sensitivity of NSCLC cells to radiotherapy, which may provide potential therapeutic targets and new strategies for combatting NSCLC resistance to radiotherapy.

MiR-221-3p-mediated downregulation of MDM2 reverses the paclitaxel resistance of non-small cell lung cancer in vitro and in vivo

MicroRNAs (miRNAs) are involved in the initiation and development of cancer and participate in drug resistance. Paclitaxel (PTX) is a first-line chemotherapy drug for advanced non-small cell lung cancer (NSCLC). The abnormal miRNA expression in NSCLC and its association with chemotherapy drug resistance remains largely unknown. The study aimed to investigate the aberrant expression of miR-221-3p in NSCLC and to elucidate its molecular mechanisms in relation to PTX resistance. PTX increased miR-221-3p expression and regulated MDM2/P53 expression in the PTX-sensitive NSCLC strain (A549). Meanwhile, miR-221-3p was rarely expressed and not interfered by PTX in PTX-resistant A549 cells (A549/Taxol). Dual-luciferase reporter assay confirmed that miR-221-3p specifically binds to MDM2 messenger RNA and inhibited MDM2 expression. The expression of MDM2 and P53 showed a negative correlation in NSCLC cell lines. MiR-221-3p down-regulation reduced the sensitivity of A549 cells to PTX, whereas its up-regulation partially reversed the A549/Taxol cells resistance to PTX and increased the chemosensitivity of A549/Taxol cells to PTX in xenograft models. Quantitative polymerase chain reaction analysis revealed that miR-221-3p expression increased, whereas the MDM2 level decreased in human NSCLC tumor tissues. Moreover, Western bolt analysis showed that P53 was lowly expressed in tumor tissues with MDM2 overexpression. Low expression of miR-221-3p in NSCLC tissues might indicate a poor T staging. In conclusion, miR-221-3p overexpression could regulate MDM2/p53 signaling pathway to reverse the PTX resistance of NSCLC and induce apoptosis in vitro and vivo.

Polyphyllin I reverses the resistance of osimertinib in non-small cell lung cancer cell through regulation of PI3K/Akt signaling

Lung cancer is considered the main cause of cancer mortality worldwide. Osimertinib, a third-generation EGFR-TKI, has been approved and administrated for treating patients with either EGFR T790M mutation or EGFR sensitive mutation. However, resistance to osimertinib emerges and has been considered to be the main obstacle in lung cancer treatment. Polyphyllin I is isolated from the natural herb Paris polyphylla and exhibits anti-cancer activities. In the present study, we identify Polyphyllin I to reverse the resistance of osimertinib in vitro and in vivo. The results showed that Polyphyllin I reversed the resistance of osimertinib through promoting apoptosis, modulating the PI3K/Akt signaling, and regulating the expression of apoptosis-related proteins in osimertinib-resistant cell lines. In vivo study confirmed the results, showing that the tumor growth was significantly suppressed in the Polyphyllin I/osimertinib group compared to the osimertinib group. It has been clarified that Polyphyllin I could reverse the resistance of osimertinib in osimertinib-resistant non-small cell of lung cancer in vitro and in vivo. The underlying mechanism might be related to the downregulation of the PI3K/Akt signaling and increase of the expression of apoptosis-related proteins, suggesting that Polyphyllin I was a promising therapeutic agent for reversing the resistance of osimertinib.

ALK inhibition activates LC3B-independent, protective autophagy in EML4-ALK positive lung cancer cells

ALK inhibitors effectively target EML4-ALK positive non-small cell lung cancer, but their effects are hampered by treatment resistance. In the present study, we asked whether ALK inhibition affects autophagy, and whether this may influence treatment response. Whereas the impact of targeted therapies on autophagic activity previously have been assessed by surrogate marker proteins such as LC3B, we here thoroughly examined effects on functional autophagic activity, i.e. on the sequestration and degradation of autophagic cargo, in addition to autophagic markers. Interestingly, the ALK inhibitor Ceritinib decreased mTOR activity and increased GFP-WIPI1 dot formation in H3122 and H2228 EML4-ALK+ lung cancer cells, suggesting autophagy activation. Moreover, an mCherry-EGFP-LC3B based assay indicated elevated LC3B carrier flux upon ALK inhibition. In accordance, autophagic cargo sequestration and long-lived protein degradation significantly increased upon ALK inhibition. Intriguingly, autophagic cargo flux was dependent on VPS34 and ULK1, but not LC3B. Co-treating H3122 cells with Ceritinib and a VPS34 inhibitor or Bafilomycin A1 resulted in reduced cell numbers. Moreover, VPS34 inhibition reduced clonogenic recovery of Ceritinib-treated cells. In summary, our results indicate that ALK inhibition triggers LC3B-independent macroautophagic flux in EML4-ALK+ cells to support cancer cell survival and clonogenic growth.

Is alectinib-induced elevation of creatine phosphokinase a predictive factor for response? Report of two cases and review of the literature

We aim to describe two cases of creatine phosphokinase (CPK) and liver enzymes elevation occurring as adverse effects of alectinib (Alecensa) treatment for anaplastic lymphoma kinase (ALK)-mutated metastatic nonsmall cell lung cancer (NSCLC). A 56-year-old female and a 59-year-old male diagnosed with NSCLC exhibiting ALK gene rearrangements were treated by alectinib administration. The former had a complete response of widespread metastatic disease within 3 months, and the latter also had a substantial response. Both patients initially experienced an episode of CPK elevation and neither had dose modifications. At the end of the treatment, CPK and liver enzymes returned to normal range despite the continuation of alectinib full dose. A transient elevation of CPK and liver enzymes may take place during the alectinib treatment, indicating a tumor tissue damage thus contributing to a significant response.

Hexokinase 2 discerns a novel circulating tumor cell population associated with poor prognosis in lung cancer patients

Unlike other epithelial cancer types, circulating tumor cells (CTCs) are less frequently detected in the peripheral blood of non-small cell lung cancer (NSCLC) patients using epithelial marker-based detection approaches despite the aggressive nature of NSCLC. Here, we demonstrate hexokinase-2 (HK2) as a metabolic function-associated marker for the detection of CTCs. In 59 NSCLC patients bearing cytokeratin-positive (CKpos) primary tumors, HK2 enables resolving cytokeratin-negative (HK2high/CKneg) CTCs as a prevalent population in about half of the peripheral blood samples with positive CTC counts. However, HK2high/CKneg tumor cells are a minority population in pleural effusions and cerebrospinal fluids. Single-cell analysis shows that HK2high/CKneg CTCs exhibit smaller sizes but consistent copy number variation profiles compared with CKpos counterparts. Single-cell transcriptome profiling reveals that CK expression levels of CTCs are independent of their epithelial-to-mesenchymal transition (EMT) status, challenging the long-standing association between CK expression and EMT. HK2high/CKneg CTCs display metastasis and EGFR inhibitor resistance-related molecular signatures and are selectively enriched in patients with EGFRL858R driver oncogene mutation as opposed to EGFR19Del , which is more frequently found in patients with prevalent CKpos CTCs in the blood. Consistently, treatment-naïve patients with a larger number or proportion of HK2high/CKneg CTCs in the blood exhibit poor therapy response and shorter progression-free survival. Collectively, our approach resolves a more complete spectrum of CTCs in NSCLC that can potentially be exploited to identify patient prognosis before therapy.

Detecting Resistance to Therapeutic ALK Inhibitors in Tumor Tissue and Liquid Biopsy Markers: An Update to a Clinical Routine Practice

The survival of most patients with advanced stage non-small cell lung cancer is prolonged by several months when they are treated with first- and next-generation inhibitors targeting ALK rearrangements, but resistance inevitably emerges. Some of the mechanisms of resistance are sensitive to novel ALK inhibitors but after an initial tumor response, more or less long-term resistance sets in. Therefore, to adapt treatment it is necessary to repeat biological sampling over time to look for different mechanisms of resistance. To this aim it is essential to obtain liquid and/or tissue biopsies to detect therapeutic targets, in particular for the analysis of different genomic alterations. This review discusses the mechanisms of resistance to therapeutics targeting genomic alterations in ALK as well as the advantages and the limitations of liquid biopsies for their identification.

Structure-Activity Relationship (SAR) Study of Spautin-1 to Entail the Discovery of Novel NEK4 Inhibitors

Lung cancer is one of the most frequently diagnosed cancers accounting for the highest number of cancer-related deaths in the world. Despite significant progress including targeted therapies and immunotherapy, the treatment of advanced lung cancer remains challenging. Targeted therapies are highly efficacious at prolonging life, but not curative. In prior work we have identified Ubiquitin Specific Protease 13 (USP13) as a potential target to significantly enhance the efficacy of mutant EGFR inhibition. The current study aimed to develop lead molecules for the treatment of epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) by developing potent USP13 inhibitors initially starting from Spautin-1, the only available USP13 inhibitor. A SAR study was performed which revealed that increasing the chain length between the secondary amine and phenyl group and introducing a halogen capable of inducing a halogen bond at position 4' of the phenyl group, dramatically increased the activity. However, we could not confirm the binding between Spautin-1 (or its analogues) and USP13 using isothermal titration calorimetry (ITC) or thermal shift assay (TSA) but do not exclude binding under physiological conditions. Nevertheless, we found that the anti-proliferative activity displayed by Spautin-1 towards EGFR-mutant NSCLC cells in vitro was at least partially associated with kinase inhibition. In this work, we present N-[2-(substituted-phenyl)ethyl]-6-fluoro-4-quinazolinamines as promising lead compounds for the treatment of NSCLC. These analogues are significantly more effective towards EGFR-mutant NSCLC cells than Spautin-1 and act as potent never in mitosis A related kinase 4 (NEK4) inhibitors (IC₅₀~1 µM) with moderate selectivity over other kinases.

Tyrosine kinase inhibitors as induction therapy in nonsmall-cell lung cancer

PURPOSE OF REVIEW

TKI therapy has shown excellent efficacy and favorable tolerability in patients with mutation-positive nonsmall cell lung cancer. However, there is no clear consensus on the role of TKI as induction therapy. In this article, we reviewed recently published studies to analyze the benefits of tyrosine kinase inhibitors, in particular, EGFR TKIs and ALK TKIs, as inducible treatments for NSCLC.

RECENT FINDINGS

Several clinical trials have recently presented their latest data, giving analysis of patient's survival benefits and adverse events. Initial results have demonstrated promising efficacy and safety data. Some clinical case reports and retrospective analysis demonstrated that EGFR/ALK TKIs can significantly improve PFS and the rate of radical surgery. However, there was no statistically significant difference in overall survival time of almost all clinical trials.

SUMMARY

TKIs are increasingly accepted by clinicians as induction therapy in NSCLC. Many studies have demonstrated that neoadjuvant therapy increases the likelihood of surgery and is associated with good resection rates, as evidenced by high prospective downstaging rates in patients with locally advanced NSCLC. However, the risk of recurrence remains high with no evidence of overall survival benefits being reported. Now that more clinical trials are being conducted and more data will be available for analysis, a clearer and more comprehensive view of what role TKIs play in induction therapy will emerge.

Detection of MET Exon 14 Skipping Alterations in Lung Cancer Clinical Samples Using a PCR-Based Approach

The receptor tyrosine kinase (RTK) c-MET plays important roles in cancer, yet despite being frequently overexpressed, clinical responses to targeting this receptor have been limited in the clinical setting. A singular significant challenge has been the accurate identification of biomarkers for the selection of responsive patients. However, recently mutations which result in the loss of exon 14 (called METex14 skipping) have emerged as novel biomarkers in non-small cell lung carcinomas (NSCLC) to predict for responsiveness to targeted therapy with c-MET inhibitors. Currently, the diverse genomic alterations responsible for METex14 skipping pose a challenge for routine clinical diagnostic testing. Next generation sequencing (NGS) is the current gold standard for identifying the diverse mutations associated with METex14, but the cost for such a procedure remains to some degree prohibitive as often NGS is requested on a case-by-case basis, and many hospitals may not even have the capacity or resources to conduct NGS.However, PCR-based approaches to detect METex14 have been developed which can be conducted in most routine hospital laboratories and may therefore allow a cost-effective approach to pre-screen patients that may respond to c-MET inhibitors prior to conducting NGS, or until all patients will have NGS conducted as routine practise. In this chapter, we describe one such PCR-based approach for screening samples for the detection of METex14 in NSCLC.

Detection of Non-Small Lung Cell Carcinoma-Associated Genetic Alterations Using a NanoString Gene Expression Platform Approach

In non-small cell lung cancer (NSCLC), mutation detection and fusion gene status are treatment predictive and, hence, key factors in clinical management. Lately, alternate splicing variants of MET have gained focus as NSCLC tumors harboring a MET exon 14 skipping event have proven sensitive toward targeted therapy. Reliable methods for detection of genetic alterations in NSCLC have proven to be of increased importance. This chapter provides with hands-on experience of the NanoString gene expression platform for detection of genetic alterations in NSCLC.

Baicalein suppresses growth of non-small cell lung carcinoma by targeting MAP4K3

Exploring key genes associated with non-small cell lung carcinoma (NSCLC) may lead to targeted therapies for NSCLC patients. The protein kinase MAP4K3 has been established as an important modulator of cell growth and autophagy in mammals. Herein, we investigated the somatic mutations and the expression pattern of MAP4K3 detected in NSCLC patients based on the TCGA database. Abnormal MAP4K3 expression and its somatic mutations are associated with the carcinogenesis and thereby becoming an attractive therapeutic target. Baicalein, a natural product, was determined to be the first-reported MAP4K3 binding ligand with its KD values of 6.47 μM measured by microscale thermophoresis. Subsequent in silico docking and mutation studies demonstrated that baicalein directly binds to MAP4K3, presumably to the substrate-binding pocket of this kinase domain, causing inactivity of MAP4K3. We further showed that baicalein could induce degradation of MAP4K3 through decreasing its stability and promoting the ubiquitin proteasome pathway. Degradation of MAP4K3 could cause dissociation of the transcription factor EB and 14-3-3 complex, enhance rapid transport of TFEB to the nucleus and trigger TFEB-dependent autophagy, resulting in lung cancer cells proliferation arrest. Knockdown of MAP4K3 expression by siRNA was sufficient to mimic baicalein-induced autophagy. Ectopic expression of the MAP4K3 protein resulted in significant resistance to baicalein-induced autophagy. Baicalein exhibited good tumor growth inhibition in a nude mouse model for human H1299 xenografts, which might be tightly related to its binding to MAP4K3 and degradation of MAP4K3. Our data provide novel mechanistic insights of baicalein/ MAP4K3/ mTORC1/ TFEB axis in regulating baicalein-induced autophagy in NSCLC, suggesting potential therapies for treatment of NSCLC.

Clathrin-mediated EGFR endocytosis as a potential therapeutic strategy for overcoming primary resistance of EGFR TKI in wild-type EGFR non-small cell lung cancer

OBJECTIVES

Oncogenic alterations of epidermal growth factor receptor (EGFR) signaling are frequently noted in non-small cell lung cancer (NSCLC). In recent decades, EGFR tyrosine kinase inhibitors (TKIs) have been developed, although the therapeutic efficacy of these inhibitor is restricted to EGFR-mutant patients. In this study, we investigated that clathrin-mediated EGFR endocytosis hampers the effects of gefitinib and sustains NSCLC cells with wild-type EGFR.

MATERIALS AND METHODS

NSCLC cell lines (H358, Calu-3, SNU-1327, and H1703) were stimulated with the EGF and treated with gefitinib and endocytosis inhibitors (phenylarsine oxide (PAO) and Filipin III). Growth inhibition and apoptosis were evaluated. Immunofluorescence, immunoprecipitation, and western blot assay were performed to investigate EGFR endocytosis and determine the signaling pathway. Xenograft mouse models were used to verify the combination effect of gefitinib and PAO in vivo.

RESULTS

We confirmed the differences in EGFR endocytosis according to gefitinib response in wild-type EGFR NSCLC cell lines. EGFR in gefitinib-sensitive and -refractory cell lines tended to internalize through distinct routes, caveolin-mediated endocytosis (CVE), and clathrin-mediated endocytosis (CME). Interestingly, while suppressing CME and CVE did not affect cell survival in sensitive cell lines significantly, CME inhibition combined with gefitinib treatment decreased cell survival and induced apoptosis in gefitinib-refractory cell lines. In addition, blocking CME in the refractory cell lines led to downregulate of p-STAT3 and inhibit nuclear localization of STAT3 in vivo, combination treatment with gefitinib and a CME inhibitor resulted in tumor regression accompanying apoptosis in xenograft mouse models.

CONCLUSION

Clathrin-mediated EGFR endocytosis contribute primary resistance of gefitinib treatment and CME inhibition combined with gefitinib could be an option in treatment of wild-type EGFR NSCLC.

CLK2 promotes occurrence and development of non-small cell lung cancer

PURPOSE

To explore the role of CDC-like kinase 2 (CLK2) in the development and progression of lung cancer and its regulatory mechanism.

METHODS

Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay was used to detect the expressions of micro ribonucleic acid (miR)-573 and CLK2 in non-small cell lung cancer (NSCLC) cell lines or tissues. The cell proliferative ability after overexpression of CLK2 was determined via cell counting kit-8 (CCK-8) and 5-Ethynyl-2'- deoxyuridine (EdU) assays. It was verified using dual-luciferase reporter assay and gain-loss assay that CLK2 was the target gene of miR-573, which was regulated by miR-573. According to the reverse assay, the effect of CLK2 on the proliferation of NSCLC cells was regulated by miR-573.

RESULTS

In qRT-PCR, the expression of CLK2 in NSCLC tissues and cell lines significantly rose. The CLK2 expression was increased in patients with stage Ⅲ-Ⅳ NSCLC and metastasis. According to survival analysis, highly-expressed CLK2 indicated a worse prognosis. The receiver operating characteristic (ROC) curves showed that CLK2 possessed the potential as a biomarker. It was found using the bioinformatics prediction that CLK2 was a potential target of miR-573. The results of dual-luciferase reporter assay confirmed that there was a binding relation between the two, and up-regulation of miR-573 could obviously inhibit the expression of CLK2. In qRT-PCR, the miR-573 expression in lung cancer tissues obviously declined, which was significantly negatively correlated with the expression of CLK2. CCK-8 and EdU assays manifested that the proliferation of lung cancer cells could be markedly enhanced through up-regulating CLK2. Finally, the results of reverse assay showed that up-regulating miR-573 could partially reverse the promoting effect of CLK2 on cell proliferation.

CONCLUSIONS

Highly-expressed CLK2 significantly enhances the proliferation of lung cancer cells, thereby promoting the occurrence and development of lung cancer, which may be regulated by miR-573.

LncRNA HAND2-AS1 inhibits proliferation and promotes apoptosis of non-small cell lung cancer cells by inactivating PI3K/Akt pathway

BACKGROUND

Non-small cell lung cancer (NSCLC) is a major subtype of lung cancer and is correlated with high incidence and mortality rate. Functionality of lncRNA HAND2-AS1 is only reported in endometrioid endometrial carcinoma and osteosarcoma. In our study, the role of HAND2-AS1 in NSCLC was investigated.

METHODS

We first detected the expression of HAND2-AS1 in lung tissues and serum of both NSCLC patients and healthy controls by qRT-PCR. Correlation between HAND2-AS1 expression level and clinical data of NSCLC patients was analyzed by Chi-square test. NSCLC cells, and cell proliferation, cell apoptosis and expression of PI3K/Akt pathway-related proteins were detected by CCK-8 assay, cell apoptosis assay and Western blot, respectively.

RESULTS

HAND2-AS1 expression was significantly down-regulated in NSCLC. HAND2-AS1 and tumor size of NSCLC patients were closely associated. Serum HAND2-AS1 can be used to effectively distinguish osteosarcoma patients from healthy controls, and it can also be used to predict prognosis of osteosarcoma patients. HAND2-AS1 overexpression inhibited osteosarcoma cell proliferation, promoted cell apoptosis, and down-regulated phosphorylation of PI3K/Akt pathway-related proteins. PI3K/Akt pathway inhibitor showed no significant effects on HAND2-AS1 expression, but reduced its effects on cell proliferation and apoptosis.

CONCLUSION

We conclude that HAND2-AS1 may suppress the proliferation of NSCLC cells by targeting PI3K/Akt pathway.

EGFR mutation testing from liquid biopsy of non-small cell lung cancer at the Institute for Oncology and Radiology of Serbia

PURPOSE

Resistance to tyrosine kinase inhibitors (TKIs) in lung cancer often occurs, so mutation testing from liquid biopsy is the method of choice as a minimally invasive approach that quickly provides information for additional therapeutic options. The purpose of this study was to assess the success rate and usefulness of EGFR testing from liquid biopsy at the Institute for Oncology and Radiology of Serbia (IORS).

METHODS

EGFR mutation testing was performed by real-time qPCR in 4750 tumor samples using the Cobas® EGFR Mutation Test v2. EGFR testing from 104 liquid biopsy samples was used to track the resistance on first-line EGFR-TKIs as well as for initial testing of 124 patients without tissue biopsies.

RESULTS

Liquid biopsy samples were tested in cases with inadequate material for DNA isolation or without tissue biopsy at diagnosis. Nine mutated samples were detected (7.3 %) with a 99.2 % testing success rate. Testing liquid biopsy samples of patients who progressed on EGFR-TKIs showed an accordance rate of 67% with driver mutations, and 49% of mutated patients had the T790M mutation which rendered them eligible for third-generation EGFR-TKIs. An additional 5 patients tested EGFR wild type from plasma after progression were rebiopsied and 3 of them had the T790M mutation.

CONCLUSIONS

EGFR mutation testing from liquid biopsy has been successfully implemented in Serbia and has proven invaluable for detecting molecular resistance mechanisms to EGFR-TKIs and as an alternative sample source for patients with scarce biopsy material or without any at all.

Ceritinib in Japanese patients with anaplastic lymphoma kinase (ALK)+ non-small cell lung cancer: interim analysis results of a post-marketing surveillance study

Ceritinib is a selective anaplastic lymphoma kinase (ALK) inhibitor approved for the treatment of patients with unresectable advanced and/or recurrent ALK fusion gene-positive non-small cell lung cancer (NSCLC). As per the approval condition in Japan, this post-marketing surveillance (PMS) study evaluated the clinical safety (including adverse events [AEs], adverse drug reactions [ADRs] and priority investigation items) and efficacy (including ORR and PFS) of ceritinib in Japanese patients. Interim analysis was conducted ~ 2 years after the start of this non-interventional, multicentre, uncontrolled, open-label, special drug-use investigation and results are reported from March 28, 2016 to April 28, 2018. Each patient was followed up for 1 year. Most patients started treatment with 750 mg ceritinib. Safety profile was similar to that observed at the time of approval. No new AEs or ADRs with incidences higher than that at approval were identified. The rate of gastrointestinal ADRs (nausea, vomiting and diarrhoea) was 73.64%. Meaningful efficacy was observed in both post-crizotinib and post-alectinib settings, with ORR of 29.55% (95% CI 20.29-40.22) and disease control rate of 53.41% (95% CI 42.46-64.12). No concerns regarding the safety and efficacy of ceritinib were identified. No new measures, including modification of the PMS study protocol, are considered necessary.

Analyses of expressions and prognostic values of Polo-like kinases in non-small cell lung cancer

BACKGROUND

Despite great advances in its early diagnosis and treatment, lung cancer is still an intractable disease and the second leading cause of cancer-related deaths and morbidity in the world. The family of Polo-like kinases (PLKs) consists of five serine/threonine kinases, which have been reported to participate in various human diseases. However, the expression and prognostic value of each PLK in human lung cancer have not been fully understood. This study analyzed mRNA expression and prognostic value of different PLKs in human non-small cell lung cancer (NSCLC).

METHODS

First, mRNA expression of PLKs in patients with NSCLC from the Oncomine and the Gene Expression Profiling Interactive Analysis (GEPIA) database was investigated. Then, a Kaplan-Meier plotter was employed for survival analysis. The sequence alteration for PLKs was analyzed using The Cancer Genome Atlas (TCGA) and the cBioPortal database. Additionally, we analyzed the association among different PLKs using the LinkedOmics database. Finally, the enrichment analysis of PLKs was achieved using the DAVID database.

RESULTS

The mRNA expression levels of PLK1 and PLK4 were significantly overexpressed, while mRNA expression level of PLK3 was underexpressed in patients with NSCLC. mRNA expressions of PLK1 and PLK4 were significantly and positively related to the tumor stage of NSCLC. Increased expressions of PLK1, PLK4, and PLK5 and decreased expression of PLK2 were attributed to limited overall survival time in NSCLC. PLK1 was positively correlated with PLK4 via the LinkedOmics database.

CONCLUSIONS

PLKs are relevant targets for NSCLC treatment, especially PLK1 and PLK4.

Ectonucleotidase CD73 and CD39 expression in non-small cell lung cancer relates to hypoxia and immunosuppressive pathways

AIMS

Adenosine triphosphate (ATP) is released at a high concentration in the tumor microenvironment. The overexpression of ectonucleotidases in non-small-cell lung cancer (NSCLC), metabolizing ΑΤP to the immunosuppressive adenosine, is studied.

MATERIALS AND METHODS

We examined the expression of the ectonucleotidases CD73 and CD39 in NSCLC in parallel with immunological parameters and markers of hypoxia and anaerobic metabolism. In vitro experiments with A549 and H1299 lung cancer cell lines were also conducted.

RESULTS

CD73 and CD39 were not expressed by normal bronchial and alveolar epithelium. In contrast, these were overexpressed by cancer cells, cancer-associated fibroblasts (CAFs), and tumor-infiltrating lymphocytes (TILs). High CD73 cancer cell expression was directly linked with lactate dehydrogenase LDH5 and with hypoxia-inducible factor HIF1α expression by cancer cells. The expression of CD39 by CAFs was directly linked with PD-L1 expression by cancer cells. A significant abundance of FOXP3+ and PD-1+ TILs was noted in tumors with high CD73 and CD39 stroma expression. In in vitro experiments, hypoxia and acidity induced CD73 mRNA and protein levels in cancer cell lines. Exposure of cancer cell lines to adenosine induced the expression of PD-L1 and LDHA mRNA and protein levels.

CONCLUSION

Ectonucleotidases are up-regulated in cancer cells, CAFs, and TILs in lung tumors. Such overexpression is linked with regulatory TIL-phenotype and PD-L1 up-regulation by cancer cells. Overexpression of LDH5 is up-regulated by adenosine, creating a vicious cycle, as the high amounts of ATP produced by LDH5-mediated anaerobic glycolysis promote the production of adenosine by a tumor microenvironment rich in ectonucleotidases.

FCHSD2 controls oncogenic ERK1/2 signaling outcome by regulating endocytic trafficking

The evolution of transformed cancer cells into metastatic tumors is, in part, driven by altered intracellular signaling downstream of receptor tyrosine kinases (RTKs). The surface levels and activity of RTKs are governed mainly through clathrin-mediated endocytosis (CME), endosomal recycling, or degradation. In turn, oncogenic signaling downstream of RTKs can reciprocally regulate endocytic trafficking by creating feedback loops in cells to enhance tumor progression. We previously showed that FCH/F-BAR and Double SH3 Domain-Containing Protein (FCHSD2) has a cancer-cell specific function in regulating CME in non-small-cell lung cancer (NSCLC) cells. Here, we report that FCHSD2 loss impacts recycling of the RTKs, epidermal growth factor receptor (EGFR) and proto-oncogene c-Met (MET), and shunts their trafficking into late endosomes and lysosomal degradation. Notably, FCHSD2 depletion results in the nuclear translocation of active extracellular signal-regulated kinase 1 and 2 (ERK1/2), leading to enhanced transcription and up-regulation of EGFR and MET. The small GTPase, Ras-related protein Rab-7A (Rab7), is essential for the FCHSD2 depletion-induced effects. Correspondingly, FCHSD2 loss correlates to higher tumor grades of NSCLC. Clinically, NSCLC patients expressing high FCHSD2 exhibit elevated survival, whereas patients with high Rab7 expression display decreased survival rates. Our study provides new insight into the molecular nexus for crosstalk between oncogenic signaling and RTK trafficking that controls cancer progression.

β-elemene suppresses Warburg effect in NCI-H1650 non-small-cell lung cancer cells by regulating the miR-301a-3p/AMPKα axis

β-elemene has been evidenced to suppress the development of numerous cancers including lung cancer. Previous research has found that in A549 cells, β-elemene increased the expression of adenosine monophosphate-activated protein kinase (AMPK) α (AMPKα), which negatively regulates the Warburg effect. Bioinformatics predicted that binding sites exist between AMPKα and miR-301a-3p, an miRNA that has shown oncogenic function in many cancers. The aim of this work was to investigate the effect of β-elemene on the Warburg effect in non-small-cell lung cancer (NSCLC) cells and its mechanism. Herein, the expression of miR-301a-3p was evaluated in NSCLC cells. Then, miR-301a-3p was overexpressed or silenced by mimics or inhibitors, respectively, followed by treatment with AMPK agonists or antagonists. NSCLC cells subjected to miR-301a-3p overexpression or inhibition were further treated with β-elemene. The results demonstrated that AMPKα was targeted and negatively regulated by miR-301a-3p. AMPKα agonists attenuated the Warburg effect in NSCLC cells induced by miR-301a-3p, as evidenced by the decrease in glucose level, lactic acid level, and expression of metabolism-related enzymes (glucose transporter 1 (GLUT1), hexokinase 1 (HK1), and lactate dehydrogenase A (LDHA)). Additionally, β-elemene suppressed the expression of miR-301a-3p, enhanced that of AMPKα, and inhibited the Warburg effect in NSCLC cells. The results indicated that β-elemene attenuates the Warburg effect in NSCLC cells, possibly by mediating the miR-301a-3p/AMPKα axis.

NNT in NSCLC: No need to worry?

In this study, Ward et al. (https://doi.org/10.1084/jem.20191689) provide exciting evidence that nucleotide nicotinamide transhydrogenase (NNT), a mitochondrial matrix-located enzyme harnessing the proton gradient to generate NADPH using NADH, markedly contributes to non-small cell lung carcinoma (NSCLC), which is abrogated in the murine C57BL/6J background, a strain known to be deficient in NNT.

The Impact of EGFR Mutation Status and Brain Metastasis for Non-Small Cell Lung Cancer Treated with Ramucirumab plus Docetaxel

OBJECTIVES

Currently, combination therapy of ramucirumab (RAM) + docetaxel (DOC) must play a more important role as a second-line treatment. Epithelial growth factor receptor (EGFR) mutation accounts for around 50% of oncogenic driver mutations in patients with advanced non-small cell lung cancer (NSCLC) in Asian subsets. The number of brain metastases (BM) is relatively higher in EGFR mutation-positive patients compared to EGFR wild-type patients. The objective of this study is to evaluate the efficacy of RAM + DOC focusing on EGFR mutation and BM.

METHODS

We retrospectively reviewed consecutive advanced NSCLC patients who received combination therapy of RAM + DOC at three institutions. A total of 112 patients with NSCLC were enrolled for efficacy analyses. We evaluated the efficacy of RAM + DOC for EGFR-mutated NSCLC with endpoints including progression-free survival (PFS), time to treatment failure (TTF) and overall survival.

RESULTS

Median PFS was 5.7 months for the EGFR mutant group compared with 3.6 months for the EGFR wild-type group (HR 0.53, 95% CI 0.32-0.87; p = 0.01). Median TTF was 5.1 months for the EGFR mutant group compared with 2.8 months for the EGFR wild-type group (HR 0.53, 95% CI 0.33-0.85; p = 0.007). Median PFS and TTF of the EGFR mutant group was significantly longer than median PFS and TTF of the EGFR wild-type group. The multivariate analysis identified EGFR mutation status as an independent favorable factor of PFS. In subset analyses of BM, median PFS of the EGFR mutant group (2.8 months) was significantly shorter than that of the EGFR wild-type group (5.1 months) (HR 7.27, 95% CI 1.78-29.68; p = 0.002).

CONCLUSION

This study revealed that EGFR mutation status and BM might be predictive or prognostic factors for PFS.

MRP1-Collateral Sensitizers as a Novel Therapeutic Approach in Resistant Cancer Therapy: An In Vitro and In Vivo Study in Lung Resistant Tumor

Multidrug resistance (MDR) is the main obstacle to current chemotherapy and it is mainly due to the overexpression of some efflux transporters such as MRP1. One of the most studied strategies to overcome MDR has been the inhibition of MDR pumps through small molecules, but its translation into the clinic unfortunately failed. Recently, a phenomenon called collateral sensitivity (CS) emerged as a new strategy to hamper MDR acting as a synthetic lethality, where the genetic changes developed upon the acquisition of resistance towards a specific agent are followed by the development of hypersensitivity towards a second agent. Among our library of sigma ligands acting as MDR modulators, we identified three compounds, F397, F400, and F421, acting as CS-promoting agents. We deepened their CS mechanisms in the "pure" model of MRP1-expressing cells (MDCK-MRP1) and in MRP1-expressing/drug resistant non-small cell lung cancer cells (A549/DX). The in vitro results demonstrated that (i) the three ligands are highly cytotoxic for MRP1-expressing cells; (ii) their effect is MRP1-mediated; (iii) they increase the cytotoxicity induced by cis-Pt, the therapeutic agent commonly used in the treatment of lung tumors; and (iv) their effect is ROS-mediated. Moreover, a preclinical in vivo study performed in lung tumor xenografts confirms the in vitro findings, making the three CS-promoting agents candidates for a novel therapeutic approach in lung resistant tumors.

Cell adhesion molecule 4 suppresses cell growth and metastasis by inhibiting the Akt signaling pathway in non-small cell lung cancer

Cell adhesion molecule 4 (CADM4) is downregulated in many human cancers. However, CADM4 expression levels in human non-small cell lung cancer (NSCLC) tissues and its roles in NSCLC progression remain unknown. Our study aims to address these issues. We examined CADM4 levels in NSCLC tissues using real-time PCR and western blot. A549 and NCI-H1299 cells were then transfected with pcDNA3.1-CADM4 plasmid or siCADM4 to overexpress or knock down CADM4. Cell proliferation, cell cycle distribution, migration, and invasion were evaluated. NSCLC cells transfected with pcDNA3.1-CADM4 plasmid or siCADM4 were treated with SC79 or LY294002, respectively, to investigate the involvement of the Akt signaling pathway. Male nude mice were subcutaneously injected with stably transfected cells (1 × 10⁶ cells/mice) to observe tumor growth. Stable transfectants were injected into nude mice (1 × 10⁶ cells/mice) via tail vein to observe tumor metastasis. The results showed that CADM4 gene and protein levels in NSCLC tissues were significantly lower than those in corresponding adjacent tissues. CADM4 overexpression markedly inhibited cell proliferation, migration, and invasion. We also found that matrix metalloproteinase 9 (MMP-9) and MMP-2 activities were reduced. Moreover, CADM4 overexpression arrested the cell cycle at G1 phase, with the changes in expression of cell cycle regulators. The Akt signaling pathway was inhibited by CADM4 overexpression. In contrast, CADM4 knockdown showed the opposite effects. Additionally, SC79 and LY294002 reversed the effects of CADM4 overexpression and CADM4 knockdown in vitro, respectively. In xenograft models, CAMD4 overexpression suppressed, while CADM4 knockdown promoted tumor growth, accompanied by changes in Ki67 expression. In in vivo metastasis assay, CADM4 overexpression decreased, while CADM4 knockdown increased numbers of metastatic nodules in lung and liver. These evidences suggest that CADM4 may regulate NSCLC progression via the Akt signaling pathway. CADM4 may be a potential therapeutic target for NSCLC.

Carbonic anhydrase 9 (CA9) expression in non-small-cell lung cancer: correlation with regulatory FOXP3+T-cell tumour stroma infiltration

BACKGROUND

Low pH suppresses the proliferation and cytotoxic activity of CD8+ cytotoxic and natural killer lymphocytes. The hypoxia-regulated transmembrane protein, carbonic anhydrase CA9, converts carbon dioxide produced by the Krebs cycle to bicarbonate and protons that acidify the extracellular milieu. We examined whether CA9 is also involved in intratumoural immunosuppression pathways.

METHODS

A series of 98 tissue samples of primary non-small-cell lung carcinomas (NSCLC) from patients treated with surgery were analysed for the expression of CA9 and programmed-death ligand PD-L1 by cancer cells, and of FOXP3 by tumour-infiltrating lymphocytes (TILs).

RESULTS

There was no direct association of CA9 with PD-L1 expression or the density of TILs in the tumour stroma, but CA9 was directly related to the extent of FOXP3+ TIL density (p = 0.008). Double-stratification survival analysis showed that patients with high CA9 expression and low TIL score had significantly poorer survival compared with all other groups (p < 0.04). In a multivariate analysis stage (p < 0.0001, HR 1.95, 95% CI: 1.3-2.7), TIL score (p = 0.05, HR 0.55, 95% CI: 0.2-1.0) was an independent prognostic variable of death events. CA9 expression by cancer cells is associated significantly with FOXP3+ regulatory T-cell abundance in the tumour stroma of NSCLC.

CONCLUSION

The study provides a basis for testing CA9 as a marker of resistance to immune-checkpoint inhibitors and as a therapeutic target to enhance the efficacy of immunotherapy.

ALK inhibitors for non-small cell lung cancer: A systematic review and network meta-analysis

BACKGROUND

We sought to assess the relative effects of individual anaplastic lymphoma kinase (ALK) inhibitors for the treatment of non-small cell lung cancer (NSCLC).

METHODS

We searched MEDLINE, Embase, Cochrane CENTRAL, and grey literature (July 23, 2019) for randomized controlled trials (RCTs) that included participants with ALK- or ROS1-positive NSCLC who received any ALK inhibitor compared with placebo, another ALK inhibitor, or the same ALK inhibitor at a different dose. The primary outcome was treatment-related death. Secondary outcomes were overall survival (OS), progression-free survival (PFS), and serious adverse events. Data were pooled via meta-analysis and network meta-analysis, and risk of bias was assessed. PROSPERO: CRD42017077046.

RESULTS

Thirteen RCTs reporting outcomes of interest among participants with ALK-positive NSCLC were identified. Treatment-related deaths were rare, with 10 deaths attributed to crizotinib (risk difference v. chemotherapy: 0.49, 95% credible interval [CrI] -0.16 to 1.46; odds ratio 2.58 (0.76-11.37). All ALK inhibitors improved PSF relative to chemotherapy (hazard ratio [95% CrI]: crizotinib 0.46 [0.39-0.54]; ceritinib 0.52 [0.42-0.64]; alectinib 300 BID 0.16 [0.08-0.33]; alectinib 600 BID 0.23 [0.17-0.30]; brigatinib 0.23 [0.15-0.35]), while alectinib and brigatinib improved PFS over crizotinib and ceritinib (alectinib v. crizotinib 0.34 [0.17-0.70]; alectinib v. ceritinib 0.30 [0.14-0.64]; brigatinib v. crizotinib 0.49 [0.33-0.73]; brigatinib v. ceritinib 0.43 [0.27-0.70]). OS was improved with alectinib compared with chemotherapy (HR 0.57 [95% CrI 0.39-0.83]) and crizotinib (0.68 [0.48-0.96]). Use of crizotinib (odds ratio 2.08 [95% CrI 1.56-2.79]) and alectinib (1.60 [1.00-2.58]) but not ceritinib (1.25 [0.90-1.74), increased the risk of serious adverse events compared with chemotherapy. Results were generally consistent among treatment-experienced or naïve participants.

CONCLUSION(S)

Treatment-related deaths were infrequent among ALK-positive NSCLC. PFS may be improved by alectinib and brigatinib relative to other ALK inhibitors; however, the assessment of OS is likely confounded by treatment crossover and should be interpreted with caution.

Sequential blinded treatment decisions in ALK-positive non-small cell lung cancers in the era of precision medicine

Next-generation ALK TKIs have become the new standard of care in first-line setting in advanced ALK-positive NSCLC patients. However, sequential strategies at progression are relevant, as may have an impact on patients' outcome. In this commentary we discuss whether genomic-tailored strategies at progression would be more suitable for improving outcome of ALK-positive NSCLC patients.

Gefitinib Versus Gefitinib Plus Pemetrexed and Carboplatin Chemotherapy in EGFR-Mutated Lung Cancer

PURPOSE

Standard first-line therapy for EGFR-mutant advanced non-small-cell lung cancer (NSCLC) is an epidermal growth factor receptor (EGFR)-directed oral tyrosine kinase inhibitor. Adding pemetrexed and carboplatin chemotherapy to an oral tyrosine kinase inhibitor may improve outcomes.

PATIENTS AND METHODS

This was a phase III randomized trial in patients with advanced NSCLC harboring an EGFR-sensitizing mutation and a performance status of 0 to 2 who were planned to receive first-line palliative therapy. Random assignment was 1:1 to gefitinib 250 mg orally per day (Gef) or gefitinib 250 mg orally per day plus pemetrexed 500 mg/m² and carboplatin area under curve 5 intravenously every 3 weeks for four cycles, followed by maintenance pemetrexed (gefitinib plus chemotherapy [Gef+C]). The primary end point was progression-free survival (PFS); secondary end points included overall survival (OS), response rate, and toxicity.

RESULTS

Between 2016 and 2018, 350 patients were randomly assigned to Gef (n = 176) and Gef+C (n = 174). Twenty-one percent of patients had a performance status of 2, and 18% of patients had brain metastases. Median follow-up time was 17 months (range, 7 to 30 months). Radiologic response rates were 75% and 63% in the Gef+C and Gef arms, respectively (P = .01). Estimated median PFS was significantly longer with Gef+C than Gef (16 months [95% CI, 13.5 to 18.5 months] v 8 months [95% CI, 7.0 to 9.0 months], respectively; hazard ratio for disease progression or death, 0.51 [95% CI, 0.39 to 0.66]; P < .001). Estimated median OS was significantly longer with Gef+C than Gef (not reached v 17 months [95% CI, 13.5 to 20.5 months]; hazard ratio for death, 0.45 [95% CI, 0.31 to 0.65]; P < .001). Clinically relevant grade 3 or greater toxicities occurred in 51% and 25% of patients in the Gef+C and Gef arms, respectively (P < .001).

CONCLUSION

Adding pemetrexed and carboplatin chemotherapy to gefitinib significantly prolonged PFS and OS but increased toxicity in patients with NSCLC.

Effect of Osimertinib on the expression of serum mmp-7 and mmp-9 in patients with non-small cell lung cancer

The purpose was to investigate the efficacy and safety of Osimertinib in the treatment of advanced non-small cell lung cancer and to analyze its effects on the expression of serum matrix metalloproteinase-7 (MMP-7) and matrix metallo-proteinase-9 (MMP-9). Eighty patients were equally divided into observation and control group. The observation group was given Osimertinib combined with conventional chemotherapy and the other was treated with conventional chemotherapy alone. The short-term efficacy, the levels of serum MMP-7, MMP-9 and adverse reactions were compared. The effectiveness and clinical benefit rate of the observation group were 62.50% and 92.50% respectively, significantly higher than the control group. There was no significant difference in MMP-7 and MMP-9 before treatment however there was a significant difference after treatment, and the serum MMP-7 & MMP-9 levels showed a trend of increasing with decreasing efficacy. After treatment, comparing with control group, serum MMP-7 and MMP-9 levels were significantly lower, the Karnofsky score was significantly higher, and the improvement effect of the quality of life was statistically significant. Besides, the incidence of leukopenia, thrombocytopenia, anemia and gastrointestinal symptoms were significantly lower. In the treatment of patients with advanced non-small cell lung cancer, Osimertinib significantly reduced the expression of serum MMP-7, MMP-9, improved the clinical benefit and quality of life of patients. The clinical efficacy was significant with a high safety.

Combination therapy of gefitinib and miR-30a-5p may overcome acquired drug resistance through regulating the PI3K/AKT pathway in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) patients with an epidermal growth factor receptor (EGFR) mutation often initially respond to EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment but may acquire drug resistance due to multiple factors. MicroRNAs are a class of small noncoding and endogenous RNA molecules that may play a role in overcoming the resistance.

MATERIALS AND METHODS

In this study, we explored and validated, through in vitro experiments and in vivo models, the ability of a combination treatment of EGFR-TKI, namely gefitinib, and a microRNA mimic, miR-30a-5p, to overcome drug resistance through regulation of the insulin-like growth factor receptor-1 (IGF1R) and hepatocyte growth factor receptor signaling pathways, which all converge on phosphatidylinositol 3 kinase (PI3K), in NSCLC. First, we examined the hypothesized mechanisms of drug resistance in H1650, H1650-acquired gefitinib-resistance (H1650GR), H1975, and H460 cell lines. Next, we investigated a potential combination treatment approach to overcome acquired drug resistance in the H1650GR cell line and an H1650GR cell implanted mouse model.

RESULTS

Dual inhibitors of EGFR and IGF1R significantly lowered the expression levels of phosphorylated protein kinase B (p-AKT) and phosphorylated mitogen-activated protein kinase (p-ERK) compared with the control group in all cell lines. With the ability to repress PI3K expression, miR-30a-5p mimics induced cell apoptosis, and inhibited cell invasion and migration in the treated H1650GR cell line.

CONCLUSION

Gefitinib, combined with miR-30a-5p mimics, effectively suppressed the growth of H1650GR-induced tumor in xenografts. Hence, a combination therapy of gefitinib and miR-30a-5p may play a critical role in overcoming acquired resistance to EGFR-TKIs. The reviews of this paper are available via the supplemental material section.

Tyrosine Kinase Inhibitors for the Treatment of EGFR Mutation-Positive Non-Small-Cell Lung Cancer: A Clash of the Generations

The availability of 3 generations of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) with different pharmacologic characteristics and clinical profiles has provided oncologists with a potentially confusing choice for the treatment of EGFR mutation-positive non-small-cell lung cancer. Although recent head-to-head clinical trials have demonstrated improved efficacy with second-generation (ie, afatinib, dacomitinib) and third-generation (ie, osimertinib) TKIs compared with the first-generation TKIs (eg, erlotinib, gefitinib), acquired resistance has been inevitable, regardless of which agent has been chosen as first-line therapy. Thus, the potential availability of subsequent treatment options is an important consideration. Recent data have demonstrated that osimertinib confers an overall survival benefit compared with first-generation EGFR TKIs, and dacomitinib has shown an overall survival benefit compared with gefitinib in an exploratory analysis. However, the relative benefits of different sequential EGFR-TKI regimens, especially those involving second- and third-generation agents, have remained uncertain and require prospective evaluation. Few such data currently exist to inform treatment choices. In the present review, we examined the pharmacologic characteristics and current clinical data for EGFR TKIs, including emerging information on the molecular mechanisms of resistance across the different generations of TKIs. Given the uncertainties regarding the optimal treatment choice, we have focused on the factors that might help determine the treatment decisions, such as efficacy and safety in patient subgroups. We also discussed the emerging real-world data, which have provided some insights into the benefits of sequential regimens in everyday clinical practice.

SP1-mediated overexpression of lncRNA LINC01234 as a ceRNA facilitates non-small-cell lung cancer progression via regulating OTUB1

Long noncoding RNAs (lncRNAs) have been confirmed to be strongly associated with the progression of various types of cancer. LncRNA LINC01234 (LINC01234) is a newly identified tumor-related lncRNA whose upregulation has been confirmed in some tumors. However, its potential expressions and possible functions in non-small-cell lung cancer (NSCLC) have not been explored. In this study, we first found that LINC01234 expressions were distinctly upregulated in both NSCLC samples and cell lines using RT-PCR. Our group also showed that LINC01234 upregulations were modulated by nuclear transcription factor SP1. The results form clinical investigations indicated that high LINC01234 expressions were associated with positively lymph node metastasis and advanced tumor-metastasis-node (TMN) stage. Kaplan-Meier assays indicated that patients with NSCLC having high LINC01234 expressions tend to have unfavorable clinical prognosis. Using multivariate assays, it was confirmed that LINC01234 was an independent prognostic factor for patients with NSCLC. In vitro assays showed that inhibition of LINC01234 suppressed NSCLC cell proliferation, cell colony formation and metastasis, and greatly promoted apoptosis. Mechanistic investigations revealed LINC01234 promotes the progression of NSCLC cells by the modulation of miR-140 to positively regulate OTUB1 expression. Taken together our findings, they provided an exhaustive assay of LINC01234 in NSCLC and imperative clues for insights into the potential effects of lncRNAs-miRNAs regulatory network in NSCLC.

BIBR1532, a Selective Telomerase Inhibitor, Enhances Radiosensitivity of Non-Small Cell Lung Cancer Through Increasing Telomere Dysfunction and ATM/CHK1 Inhibition

PURPOSE

Telomerase is reactivated in non-small cell lung cancer (NSCLC), and it increases cell resistance to irradiation through protecting damaged telomeres and enhancing DNA damage repair. We investigated the radiosensitizing effect of BIBR1532, a highly selective telomerase inhibitor, and its corresponding mechanism in NSCLC.

METHODS AND MATERIALS

Cell proliferation, telomerase activity, and telomere dysfunction-induced foci were measured with CCK-8 assay, real-time fluorescent quantitative polymerase chain reaction, and immunofluorescence. The effect of BIBR1532 on the response of NSCLC cells to radiation was analyzed using clonogenic survival and xenograft tumor assays. Cell death and cell senescence induced by BIBR1532 or ionizing radiation (IR), or both, were detected with western blotting, flow cytometry, and senescence-association β-galactosidase staining assay.

RESULTS

We observed dose-dependent direct cytotoxicity of BIBR1532 at relatively high concentrations in NSCLC cells. Low concentrations of BIBR1532 did not appear toxic to NSCLC cells; however, they substantially increased the therapeutic efficacy of IR in vitro by enhancing IR-induced apoptosis, senescence, and mitotic catastrophe. Moreover, in a mouse xenograft model, BIBR1532 treatment synergized with IR at nontoxic dose levels promoted the antitumor efficacy of IR without toxicity to hematologic and internal organs. Mechanistically, lower concentrations of BIBR1532 effectively inhibited telomerase activity and increased IR-induced telomere dysfunction, resulting in disruption of chromosomal stability and inhibition of the ATM/CHK1 (ataxia-telangiectasia-mutated/Checkpoint kinase 1) pathway, which impaired DNA damage repair.

CONCLUSIONS

Our findings demonstrate that disturbances in telomerase function by nontoxic dose levels of BIBR1532 effectively enhance the radiosensitivity of NSCLC cells. This finding provides a rationale for the clinical assessment of BIBR1532 as a radiosensitizer.

Value of serum tumor markers for predicting EGFR mutations and positive ALK expression in 1089 Chinese non-small-cell lung cancer patients: A retrospective analysis

PURPOSE

The role of serum tumor markers (STMs) in the modern management of epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) mutations in lung cancer remains poorly described. In this study, we investigated whether STMs could be a valuable noninvasive tool to predict EGFR mutations and ALK positivity in non-small-cell lung cancer (NSCLC) patients.

EXPERIMENTAL DESIGN

We retrospectively reviewed and included 1089 NSCLC patients who underwent EGFR or ALK mutation testing and STMs measurement prior to treatment. The differences in several clinical characteristics and STMs between the subgroups were analyzed. Multivariate logistic regression analysis was performed to identify predictors of EGFR mutations and ALK positivity.

RESULTS

EGFR mutations were found more frequently in females (63.11%), never-smokers (59.69%), and those with lung adenocarcinoma (ADC) (53.87%). Negative carbohydrate antigen (CA) 125, ferritin (FERR), squamous cell carcinoma antigen (SCC), and soluble fragment of cytokeratin 19 (CYFRA 21-1) levels were significantly associated with EGFR mutations (p < 0.05). Multivariate analysis demonstrated that ADC, never-smoker status, and negative CA 125 and SCC results were predictors of EGFR mutations (p < 0.05). The receiver operating characteristic (ROC) curve yielded an area under the curve (AUC) of 0.715 (95% confidence interval [CI]: 0.673-0.758) for the combination of the four factors. Positive ALK expression was found more frequently in younger patients (median age: 49 years), females (8.40%), never-smokers (8.82%), and those negative for carcinoembryonic antigen (CEA) (8.02%). Multivariate analysis demonstrated that younger age and never-smoker status were the only independent predictors of ALK positivity (p < 0.05). The ROC curve yielded an AUC of 0.760 (95% CI: 0.677-0.844) for the combination of these two factors.

CONCLUSION

STMs are associated with mutant EGFR status and could be integrated with other clinical factors to enhance the ability to distinguish EGFR mutation status among NSCLC patients. For ALK-positive patients, younger age and never-smoker status could predict the mutation status, whereas STMs could not.

Methionyl-tRNA Synthetase is a Useful Diagnostic Marker for Lymph Node Metastasis in Non-Small Cell Lung Cancer

PURPOSE

Identification of lymph node (LN) metastasis in non-small cell lung cancer (NSCLC) is critical for disease staging and selection of therapeutic modalities. Sometimes it is not possible to obtain LN core tissue by endobronchial ultrasound-guided transbronchial needle aspirate (EBUS-TBNA), resulting in low diagnostic yield.

MATERIALS AND METHODS

In this study, 138 specimens were collected from 108 patients who underwent EBUS-TBNA under the suspicion of LN metastasis of NSCLC. Diagnostic yields of anti-CD45 and anti-methionyl-tRNA synthetase (MRS), immunofluorescent (IF) staining on cytology specimens were compared with those of conventional cytology and positron emission tomography-computed tomography (PET-CT).

RESULTS

MRS was strongly expressed in NSCLC cells metastasized to LNs, but weakly expressed in cells at the periphery of the LN germinal center. The majority of cells were CD20 positive, although a few cells were either CD3 or CD14 positive, indicating that CD45 staining is required for discrimination of non-malignant LN constituent cells from NSCLC cells. When the diagnostic efficacy of MRS/CD45 IF staining was evaluated using 138 LN cellular aspirates from 108 patients through EBUS-TBNA, the sensitivity was 76.7% and specificity was 90.8%, whereas those of conventional cytology test were 71.8% and 100.0%, respectively. Combining the results of conventional cytology testing and those of PET-CT showed a sensitivity and specificity of 71.6% and 100%, and the addition of MRS/CD45 dual IF data to this combination increased sensitivity and specificity to 85.1% and 97.8%, respectively.

CONCLUSION

MRS/CD45 dual IF staining showed good diagnostic performance and may be a good tool complementing conventional cytology test for determining LN metastasis of NSCLC.

Evaluation of PAP in EGFR Mutational Testing in Advanced NSCLC: a Comparative Study

BACKGROUND

EGFR mutational testing is crucial for advanced non-squamous NSCLC. PAP is a sensitive and selective method to detect rare mutations.

METHODS

Eighty-five patients with non-squamous NSCLC were enrolled in this study. A set of paired plasma samples from each patient were collected and detected by PAP and ARMS.

RESULTS

Of 85 paired samples, 78.8% (67/85) presented the same mutational status by the two methods. There was no statistically significant difference between the mutation frequencies in plasma samples detected with PAP and ARMS (p = 0.096).

CONCLUSIONS

PAP technology appears to be an alternative choice with relatively high sensitivity for the detection of plasma EGFR mutations.

Resistance mechanisms to osimertinib in EGFR-mutated non-small cell lung cancer

Osimertinib is an irreversible, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that is highly selective for EGFR-activating mutations as well as the EGFR T790M mutation in patients with advanced non-small cell lung cancer (NSCLC) with EGFR oncogene addiction. Despite the documented efficacy of osimertinib in first- and second-line settings, patients inevitably develop resistance, with no further clear-cut therapeutic options to date other than chemotherapy and locally ablative therapy for selected individuals. On account of the high degree of tumour heterogeneity and adaptive cellular signalling pathways in NSCLC, the acquired osimertinib resistance is highly heterogeneous, encompassing EGFR-dependent as well as EGFR-independent mechanisms. Furthermore, data from repeat plasma genotyping analyses have highlighted differences in the frequency and preponderance of resistance mechanisms when osimertinib is administered in a front-line versus second-line setting, underlying the discrepancies in selection pressure and clonal evolution. This review summarises the molecular mechanisms of resistance to osimertinib in patients with advanced EGFR-mutated NSCLC, including MET/HER2 amplification, activation of the RAS-mitogen-activated protein kinase (MAPK) or RAS-phosphatidylinositol 3-kinase (PI3K) pathways, novel fusion events and histological/phenotypic transformation, as well as discussing the current evidence regarding potential new approaches to counteract osimertinib resistance.

Efficacy of Osimertinib in EGFR-Mutated Non-Small Cell Lung Cancer with Leptomeningeal Metastases Pretreated with EGFR-Tyrosine Kinase Inhibitors

BACKGROUND

The prognosis of patients with non-small cell lung cancer (NSCLC) who develop leptomeningeal metastasis (LM) is poor.

OBJECTIVE

To assess the clinical efficacy of osimertinib, a third-generation tyrosine-kinase inhibitor (TKI), in patients with epidermal growth-factor receptor (EGFR)-mutated NSCLCs and LM.

PATIENTS AND METHODS

Retrospective study of NSCLC patients with osimertinib-treated EGFR-mutated NSCLC and LM.

RESULTS

Twenty patients (mean age, 61.2 years; 70% women) with adenocarcinoma NSCLC were included in the study. EGFR mutations were reported in exons 18 (n = 2), 19 (n = 7), and 21 (n = 11). Before starting osimertinib, patients had received a mean of 2.3 treatment lines. When LM was diagnosed, all patients had clinical symptoms. Sixteen (80%) patients had a performance status ≥2. At osimertinib initiation, 13 (65%) patients harbored the EGFR-T790M-resistance mutation. Osimertinib was started at 80 (n = 17), 160 (n = 2), or 40 mg/day (n = 1). All 13 (100%) patients with the T790M mutation and 4 (57%) of those without it obtained clinical responses. Among the 11 radiologically assessable patients, 9 (82%) responded, with 5 responses reported within 15 days after treatment initiation. Median overall survival and progression-free survival were 18.0 and 17.2 months, respectively, from the start of osimertinib.

CONCLUSIONS

In this non-selected population, osimertinib had remarkable efficacy in NSCLC patients with LM irrespective of the presence of the EGFR-T790M-resistance mutation. Osimertinib efficacy was rapid in several patients, even some with poor performance status.

Clinical factors affecting progression-free survival with crizotinib in ALK-positive non-small cell lung cancer

BACKGROUND/AIMS

Although crizotinib is standard chemotherapy for advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC), clinical factors affecting progression-free survival (PFS) have not been reported. The purpose of this study was to identify clinical factors affecting PFS of crizotinib and develop a prognostic model for advanced ALK-positive NSCLC.

METHODS

Clinicopathologic features of patients enrolled in PROFILE 1001, 1005, 1007, and 1014 (training cohort) were reviewed. We conducted multivariate Cox analysis for PFS and overall survival (OS) in the training cohort (n = 159) and generated a proportional hazards model based on significant clinicopathologic factors, and then validated the model in an independent validation cohort (n = 40).

RESULTS

In the training cohort, the objective response rate was 81.5%. Median PFS and OS from the start of crizotinib were 12.4 and 31.3 months, respectively. Multivariate Cox analysis showed poor performance status, number of metastatic organs (≥ 3), and no response to crizotinib independently associated shorter PFS. Based on a score derived from these three factors, median PFS and OS of patients with one or two factors were significantly shorter compared to those without these factors (median PFS, 22.4 months vs. 10.5 months vs. 6.5 months; median OS, not reached vs. 29.1 months vs. 11.8 months, respectively; p < 0.001 for each group). This model also had validated in an independent validation cohort.

CONCLUSION

Performance status, number of metastatic organs, and response to crizotinib affected PFS of crizotinib in ALK-positive NSCLC. Based on these factors, we developed a simple and useful prediction model for PFS.