Upfront Management of ALK-Rearranged Metastatic Non-small Cell Lung Cancer: One Inhibitor Fits All?

PURPOSE OF REVIEW: Anaplastic lymphoma kinase (ALK) rearrangements represent a seldom event in non-small cell lung cancer (NSCLC). Given the oncogene alteration, ALK targeting represents the main therapeutic strategy. Here, we review evidence regarding ALK inhibitors (ALKi): clinical activity, safety profiles, financial costs, and biomarkers of efficacy. RECENT FINDINGS: During the past 10 years, multiple ALKi have been developed, and four different compounds are currently available as upfront options for ALK+ NSCLC patients: crizotinib, ceritinib, alectinib, and brigatinib. Second-generation (2G) ALKi demonstrated superior clinical activity in terms of median progression-free survival (mPFS), objective response rate (ORR), intracranial disease control, and duration of response (DOR) when compared with crizotinib. 2G ALKi represent the current gold-standard first-line treatment for ALK-rearranged metastatic NSCLC. Among all available options, in our opinion, alectinib has likely the best profile of clinical activity and safety, thus emerging as the best upfront therapy. More insights will come from ongoing trials and analysis of biomarkers.

Wnt/IL-1ß/IL-8 autocrine circuitries control chemoresistance in mesothelioma initiating cells by inducing ABCB5.

Malignant pleural mesothelioma (MPM) is a tumor with high chemoresistance and poor prognosis. MPM-initiating cells (ICs) are known to be drug resistant, but it is unknown if and how stemness-related pathways determine chemoresistance. Moreover, there are no predictive markers of IC-associated chemoresistance. Aim of this work is to clarify if and by which mechanisms the chemoresistant phenotype of MPM IC was due to specific stemness-related pathways. We generated MPM IC from primary MPM samples and compared the gene expression and chemo-sensitivity profile of IC and differentiated/adherent cells (AC) of the same patient. Compared to AC, IC had upregulated the drug efflux transporter ABCB5 that determined resistance to cisplatin and pemetrexed. ABCB5-knocked-out (KO) IC clones were resensitized to the drugs in vitro and in patient-derived xenografts. ABCB5 was transcriptionally activated by the Wnt/GSK3ß/ß-catenin/c-myc axis that also increased IL-8 and IL-1ß production. IL-8 and IL-1ß-KO IC clones reduced the c-myc-driven transcription of ABCB5 and reacquired chemosensitivity. ABCB5-KO clones had lower IL-8 and IL-1ß secretion, and c-myc transcriptional activity, suggesting that either Wnt/GSK3ß/ß-catenin and IL-8/IL-1ß signaling drive c-myc-mediated transcription of ABCB5. ABCB5 correlated with lower time-to-progression and overall survival in MPM patients treated with cisplatin and pemetrexed. Our work identified multiple autocrine loops linking stemness pathways and resistance to cisplatin and pemetrexed in MPM IC. ABCB5 may represent a new target to chemosensitize MPM IC and a potential biomarker to predict the response to the first-line chemotherapy in MPM patients.

Combinatorial targeting of nuclear export and translation of RNA inhibits aggressive B-cell lymphomas.

Aggressive double- and triple-hit (DH/TH) diffuse large B-cell lymphomas (DLBCLs) feature activation of Hsp90 stress pathways. Herein, we show that Hsp90 controls posttranscriptional dynamics of key messenger RNA (mRNA) species including those encoding BCL6, MYC, and BCL2. Using a proteomics approach, we found that Hsp90 binds to and maintains activity of eIF4E. eIF4E drives nuclear export and translation of BCL6, MYC, and BCL2 mRNA. eIF4E RNA-immunoprecipitation sequencing in DLBCL suggests that nuclear eIF4E controls an extended program that includes B-cell receptor signaling, cellular metabolism, and epigenetic regulation. Accordingly, eIF4E was required for survival of DLBCL including the most aggressive subtypes, DH/TH lymphomas. Indeed, eIF4E inhibition induces tumor regression in cell line and patient-derived tumorgrafts of TH-DLBCL, even in the presence of elevated Hsp90 activity. Targeting Hsp90 is typically limited by counterregulatory elevation of Hsp70B, which induces resistance to Hsp90 inhibitors. Surprisingly, we identify Hsp70 mRNA as an eIF4E target. In this way, eIF4E inhibition can overcome drug resistance to Hsp90 inhibitors. Accordingly, rational combinatorial inhibition of eIF4E and Hsp90 inhibitors resulted in cooperative antilymphoma activity in DH/TH DLBCL in vitro and in vivo.

The genetics of nodal marginal zone lymphoma.

Nodal marginal zone lymphoma (NMZL) is a rare, indolent B-cell tumor that is distinguished from splenic marginal zone lymphoma (SMZL) by the different pattern of dissemination. NMZL still lacks distinct markers and remains orphan of specific cancer gene lesions. By combining whole-exome sequencing, targeted sequencing of tumor-related genes, whole-transcriptome sequencing, and high-resolution single nucleotide polymorphism array analysis, we aimed at disclosing the pathways that are molecularly deregulated in NMZL and we compare the molecular profile of NMZL with that of SMZL. These analyses identified a distinctive pattern of nonsilent somatic lesions in NMZL. In 35 NMZL patients, 41 genes were found recurrently affected in ≥3 (9%) cases, including highly prevalent molecular lesions of MLL2 (also known as KMT2D; 34%), PTPRD (20%), NOTCH2 (20%), and KLF2 (17%). Mutations of PTPRD, a receptor-type protein tyrosine phosphatase regulating cell growth, were enriched in NMZL across mature B-cell tumors, functionally caused the loss of the phosphatase activity of PTPRD, and were associated with cell-cycle transcriptional program deregulation and increased proliferation index in NMZL. Although NMZL shared with SMZL a common mutation profile, NMZL harbored PTPRD lesions that were otherwise absent in SMZL. Collectively, these findings provide new insights into the genetics of NMZL, identify PTPRD lesions as a novel marker for this lymphoma across mature B-cell tumors, and support the distinction of NMZL as an independent clinicopathologic entity within the current lymphoma classification.

Integrin αvß3 acting as membrane receptor for thyroid hormones mediates angiogenesis in malignant T cells.

The interaction of lymphoid tumor cells with components of the extracellular matrix via integrin αvß3 allows tumor survival and growth. This integrin was demonstrated to be the membrane receptor for thyroid hormones (THs) in several tissues. We found that THs, acting as soluble integrin αvß3 ligands, activated growth-related signaling pathways in T-cell lymphomas (TCLs). Specifically, TH-activated αvß3 integrin signaling promoted TCL proliferation and angiogenesis, in part, via the upregulation of vascular endothelial growth factor (VEGF). Consequently, genetic or pharmacologic inhibition of integrin αvß3 decreased VEGF production and induced TCL cell death in vitro and in human xenograft models. In sum, we show that integrin αvß3 transduces prosurvival signals into TCL nuclei, suggesting a novel mechanism for the endocrine modulation of TCL pathophysiology. Targeting this mechanism could constitute an effective and potentially low-toxicity chemotherapy-free treatment of TCL patients.

Pulmonary adenocarcinoma with enteric differentiation: Dissecting oncogenic genes alterations with DNA sequencing and FISH analysis.

BACKGROUND: Pulmonary Adenocarcinoma with Enteric Differentiation (PAED) is a rare subtype of adenocarcinoma of emerging interest, recently introduced in the 2015 WHO classification. However, little is known about major molecular signatures of this class of adenocarcinomas and information about new biomarkers totally lack. METHODS: We examined the NRAS, PIK3CA, EGFR, KRAS and BRAF status through mass spectrometry sequencing and ALK rearrangement by FISH in a series of 8 PAEDs. RESULTS: 1/8 (12.5%) case had a simultaneous PIK3CA mutation (E545K) and an EML4-ALK translocation. KRAS gene showed a mutation in the codon 12 in 4/8 of PAED (50%), NRAS, BRAF and EGFR genes were wild type in all tumor samples. CONCLUSIONS: We concluded that PIK3CA mutations and ALK rearrangement occur also in PAEDs, while NRAS mutations might be a very rare event similarly to pulmonary adenocarcinomas of conventional type. KRAS is the prevailing gene mutated in this class of adenocarcinoma.

PRDM1/BLIMP1 is commonly inactivated in anaplastic large T-cell lymphoma.

Anaplastic large cell lymphoma (ALCL) is a mature T-cell lymphoma that can present as a systemic or primary cutaneous disease. Systemic ALCL represents 2% to 5% of adult lymphoma but up to 30% of all pediatric cases. Two subtypes of systemic ALCL are currently recognized on the basis of the presence of a translocation involving the anaplastic lymphoma kinase ALK gene. Despite considerable progress, several questions remain open regarding the pathogenesis of both ALCL subtypes. To investigate the molecular pathogenesis and to assess the relationship between the ALK(+) and ALK(-) ALCL subtypes, we performed a genome-wide DNA profiling using high-density, single nucleotide polymorphism arrays on a series of 64 cases and 7 cell lines. The commonest lesions were losses at 17p13 and at 6q21, encompassing the TP53 and PRDM1 genes, respectively. The latter gene, coding for BLIMP1, was inactivated by multiple mechanisms, more frequently, but not exclusively, in ALK(-)ALCL. In vitro and in vivo experiments showed that that PRDM1 is a tumor suppressor gene in ALCL models, likely acting as an antiapoptotic agent. Losses of TP53 and/or PRDM1 were present in 52% of ALK(-)ALCL, and in 29% of all ALCL cases with a clinical implication.

Beyond NPM-anaplastic lymphoma kinase driven lymphomagenesis: alternative drivers in anaplastic large cell lymphoma.

PURPOSE OF REVIEW: Anaplastic large cell lymphomas (ALCLs) are rare entities whose somatic genetic lesions have been identified only in a subset of patients. Thus, an integrated and massive discovery programme is required to define their tumourigenic alterations and to design more successful tailored therapies. RECENT FINDINGS: The discovery of anaplastic lymphoma kinase (ALK) fusions has provided the basis for the characterization of distinct subsets among ALCL patients. Although the oncogenic addiction of ALK signalling is proven, the tumorigenic contribution of coactivating lesions is still missing. As ALK- and ALK+ share common signatures, it is plausible that analogous mechanisms of transformation may be operating in both subsets, as confirmed by the dysregulated activation of c-MYC, RAS and NFκB, and the loss of Blimp-1 and p53/p63 axis. Nonetheless, recurrent genetic alterations for ALK- ALCL or refractory leukaemic ALK+ ALCL are lacking. Moreover, although conventional chemotherapies (anthracycline-based) are most successful, that is in ALK+ ALCL patients, the implementation of ALK inhibitors or of anti-CD30 based treatments provides innovative solutions, particularly in paediatric ALK+ ALCL and in chemorefractory/relapsed patients. SUMMARY: The complete portrayal of the landscape of genetic alterations in ALCL will dictate the development of innovative chemotherapeutic and targeted therapies that will fit most with the molecular and clinical profiling of individual patients.

Autocrine 17-ß-Estradiol/Estrogen Receptor-α Loop Determines the Response to Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer.

PURPOSE: The response to immune checkpoint inhibitors (ICI) often differs between genders in non-small cell lung cancer (NSCLC), but metanalyses results are controversial, and no clear mechanisms are defined. We aim at clarifying the molecular circuitries explaining the differential gender-related response to anti-PD-1/anti-PD-L1 agents in NSCLC. EXPERIMENTAL DESIGN: We prospectively analyzed a cohort of patients with NSCLC treated with ICI as a first-line approach, and we identified the molecular mechanisms determining the differential efficacy of ICI in 29 NSCLC cell lines of both genders, recapitulating patients' phenotype. We validated new immunotherapy strategies in mice bearing NSCLC patient-derived xenografts and human reconstituted immune system ("immune-PDXs"). RESULTS: In patients, we found that estrogen receptor α (ERα) was a predictive factor of response to pembrolizumab, stronger than gender and PD-L1 levels, and was directly correlated with PD-L1 expression, particularly in female patients. ERα transcriptionally upregulated CD274/PD-L1 gene, more in females than in males. This axis was activated by 17-ß-estradiol, autocrinely produced by intratumor aromatase, and by the EGFR-downstream effectors Akt and ERK1/2 that activated ERα. The efficacy of pembrolizumab in immune-PDXs was significantly improved by the aromatase inhibitor letrozole, which reduced PD-L1 and increased the percentage of antitumor CD8+T-lymphocytes, NK cells, and Vγ9Vδ2 T-lymphocytes, producing durable control and even tumor regression after continuous administration, with maximal benefit in 17-ß-estradiol/ERα highfemale immune-xenografts. CONCLUSIONS: Our work unveils that 17-ß-estradiol/ERα status predicts the response to pembrolizumab in patients with NSCLC. Second, we propose aromatase inhibitors as new gender-tailored immune-adjuvants in NSCLC. See related commentary by Valencia et al., p. 3832.

Tumor plasticity and therapeutic resistance in oncogene-addicted non-small cell lung cancer: from preclinical observations to clinical implications.

The identification of actionable targets in oncogene-addicted non-small cell lung cancer (NSCLC) has fueled biomarker-directed strategies, especially in advanced stage disease. Despite the undeniable success of molecular targeted therapies, duration of clinical response is relatively short-lived. While extraordinary efforts have defined the complexity of tumor architecture and clonal evolution at the genetic level, not equal interest has been given to the dynamic mechanisms of phenotypic adaptation engaged by cancer during treatment. At the clinical level, molecular targeted therapy of EGFR-mutant and ALK-rearranged tumors often results in epithelial-to-mesenchymal transition (EMT) and histological transformation of the original adenocarcinoma without the acquisition of additional genetic lesions, thus limiting subsequent therapeutic options and patient outcome. Here we provide an overview of the current understanding of the genetic and non-genetic molecular circuits governing this phenomenon, presenting current strategies and potentially innovative therapeutic approaches to interfere with lung cancer cell plasticity.

Efficacy of alectinib in lung adenocarcinoma patients with different anaplastic lymphoma kinase (ALK) rearrangements and co-existing alterations-a retrospective cohort study.

Background: Alectinib significantly improves survival of non-small cell lung cancer (NSCLC) patients with anaplastic lymphoma kinase (ALK)-rearrangement. In this study, we analyzed the effects of different ALK rearrangements and co-mutations on the efficacy of alectinib. Methods: Using the electronic medical record system, we reviewed in terms of clinical and pathological features patients with advanced (IIIB/IV stage) ALK-rearranged NSCLC at Shanghai Chest Hospital between January 2018 and December 2021 who were treated with alectinib in first or second line and were assessed for objective response rate (ORR), disease control rate (DCR), and progression-free survival (PFS). Results: A total of 66 patients were enrolled in the study, and 17 types of ALK rearrangements were detected, of which five types of ALK rearrangements responded well to alectinib. We classified ALK-rearrangements into four main types, namely echinoderm microtubule-associated protein-like 4 (EML4)-ALK (E6:A20), EML4-ALK (E13:A20), EML4-ALK (E20:A20), and others. There was no significant difference in ORR and DCR of these types (ORR: 31.3% vs. 13.0% vs. 18.2% vs. 17.6%, P=0.575; DCR: 93.8% vs. 95.6% vs. 100.0% vs. 88.2%, P=0.627). The 3-year PFS rates were 25.0% (4/16) vs. 13.0% (3/23) vs. 27.3% (3/11) vs. 18.8% (3/16) for EML4-ALK (E6:A20), EML4-ALK (E13:A20), EML4-ALK (E20:A20), and others, respectively (P=0.725). The results of co-mutation analysis showed that the median PFS (mPFS) for patients with tumors harboring TP53 mutations was 30.4 months, significantly shorter than that of patients with tumors without co-mutations and whose mPFS was not mature (P=0.026). TSC1 co-mutation was also identified as a detrimental factor in outcome, with a DCR of 60% vs. 100% (P=0.031), mPFS of 30.4 months vs. not applicable (P=0.160) in patients with vs. those without this co-mutation, respectively. The efficacy of alectinib in patients with brain metastases is comparable to that in patients without distant organ metastases. There were two cases with specific fusion types that also responded to alectinib; namely, double ALK-rearrangements: EML4-ALK (E13:A20) and MSH2-ALK (M7:A20), and with a rare fusion partner, SPECC1L-ALK (S8:A20). Their PFS were 8.7 and 38.0 months, respectively. Conclusions: In this study, the efficacy of alectinib in different types of ALK-rearrangements varied slightly. TP53 and TSC1 co-mutations were identified as detrimental factors affecting efficacy. This study provides references for the response to alectinib in patients with different types of ALK rearrangements and co-mutation.

Current practice of genomic profiling of patients with advanced solid tumours in Italy: the Italian Register of Actionable Mutations (RATIONAL) study.

BACKGROUND: The Italian Register of Actionable Mutations (RATIONAL) is a multicentric, observational study collecting next-generation sequencing (NGS)-based tumour profiling data of patients with advanced solid tumours. METHODS: The study enrols patients who had available an NGS-based tumour profiling (Pathway-A) or undergo comprehensive genomic profiling (CGP) with FoundationOne CDx assays within the trial (Pathway-B). The primary endpoint was the rate of actionable mutations identified. RESULTS: Sequencing data were available for 738 patients in Pathway-A (218) and -B (520). In Pathway-A, 154/218 (70.6%) tests were performed using NGS panels ≤52 genes, and genomic alterations (GAs) were found in 164/218 (75.2%) patients. In Pathway-B, CGP revealed GAs in 512/520 (98.5%) patients. Levels I/II/III actionable GAs according to the European Society of Medical Oncology Scale for Clinical Actionability of molecular Targets (ESCAT) were identified in 254/554 (45.8%) patients with non-small-cell lung cancer, cholangiocarcinoma, colorectal, gastric, pancreatic and breast cancer. The rate of patients with level I GAs was similar in Pathways A and B (69 versus 102). CGP in Pathway-B revealed a higher number of patients with level II/III GAs (99 versus 20) and potentially germline pathogenic/likely pathogenic variants (58 versus 15) as compared with standard testing in Pathway-A. In patients with cancer of unknown primary, CGP detected OncoKB levels 3B/4 GAs in 31/58 (53.4%) cases. Overall, 67/573 (11.7%) of patients received targeted therapy based on genomic testing. CONCLUSION: The Italian Register of Actionable Mutations represents the first overview of genomic profiling in Italian current clinical practice and highlights the utility of CGP for identifying therapeutic targets in selected cancer patients.

Novel Lymphocyte-Independent Antitumor Activity by PD-1 Blocking Antibody against PD-1+ Chemoresistant Lung Cancer Cells.

PURPOSE: Antibodies against the lymphocyte PD-1 (aPD-1) receptor are cornerstone agents for advanced non-small cell lung cancer (NSCLC), based on their ability to restore the exhausted antitumor immune response. Our study reports a novel, lymphocyte-independent, therapeutic activity of aPD-1 against NSCLC, blocking the tumor-intrinsic PD-1 receptors on chemoresistant cells. EXPERIMENTAL DESIGN: PD-1 in NSCLC cells was explored in vitro at baseline, including stem-like pneumospheres, and following treatment with cisplatin both at transcriptional and protein levels. PD-1 signaling and RNA sequencing were assessed. The lymphocyte-independent antitumor activity of aPD-1 was explored in vitro, by PD-1 blockade and stimulation with soluble ligand (PD-L1s), and in vivo within NSCLC xenograft models. RESULTS: We showed the existence of PD-1+ NSCLC cell subsets in cell lines and large in silico datasets (Cancer Cell Line Encyclopedia and The Cancer Genome Atlas). Cisplatin significantly increased PD-1 expression on chemo-surviving NSCLC cells (2.5-fold P = 0.0014), while the sequential treatment with anti-PD-1 Ab impaired their recovery after chemotherapy. PD-1 was found to be associated with tumor stemness features. PD-1 expression was enhanced in NSCLC stem-like pneumospheres (P < 0.0001), significantly promoted by stimulation with soluble PD-L1 (+27% ± 4, P < 0.0001) and inhibited by PD-1 blockade (-30% ± 3, P < 0.0001). The intravenous monotherapy with anti-PD-1 significantly inhibited tumor growth of NSCLC xenografts in immunodeficient mice, without the contribution of the immune system, and delayed the occurrence of chemoresistance when combined with cisplatin. CONCLUSIONS: We report first evidence of a novel lymphocyte-independent activity of anti-PD-1 antibodies in NSCLC, capable of inhibiting chemo-surviving NSCLC cells and exploitable to contrast disease relapses following chemotherapy. See related commentary by Augustin et al., p. 505.

Exploring circular MET RNA as a potential biomarker in tumors exhibiting high MET activity.

BACKGROUND: MET-driven acquired resistance is emerging with unanticipated frequency in patients relapsing upon molecular therapy treatments. However, the determination of MET amplification remains challenging using both standard and next-generation sequencing-based methodologies. Liquid biopsy is an effective, non-invasive approach to define cancer genomic profiles, track tumor evolution over time, monitor treatment response and detect molecular resistance in advance. Circular RNAs (circRNAs), a family of RNA molecules that originate from a process of back-splicing, are attracting growing interest as potential novel biomarkers for their stability in body fluids. METHODS: We identified a circRNA encoded by the MET gene (circMET) and exploited blood-derived cell-free RNA (cfRNA) and matched tumor tissues to identify, stratify and monitor advanced cancer patients molecularly characterized by high MET activity, generally associated with genomic amplification. RESULTS: Using publicly available bioinformatic tools, we discovered that the MET locus transcribes several circRNA molecules, but only one candidate, circMET, was particularly abundant. Deeper molecular analysis revealed that circMET levels positively correlated with MET expression and activity, especially in MET-amplified cells. We developed a circMET-detection strategy and, in parallel, we performed standard FISH and IHC analyses in the same specimens to assess whether circMET quantification could identify patients displaying high MET activity. Longitudinal monitoring of circMET levels in the plasma of selected patients revealed the early emergence of MET amplification as a mechanism of acquired resistance to molecular therapies. CONCLUSIONS: We found that measurement of circMET levels allows identification and tracking of patients characterized by high MET activity. Circulating circMET (ccMET) detection and analysis could be a simple, cost-effective, non-invasive approach to better implement patient stratification based on MET expression, as well as to dynamically monitor over time both therapy response and clonal evolution during treatment.

Targeting CCR7-PI3Kγ overcomes resistance to tyrosine kinase inhibitors in ALK-rearranged lymphoma.

Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) show potent efficacy in several ALK-driven tumors, but the development of resistance limits their long-term clinical impact. Although resistance mechanisms have been studied extensively in ALK-driven non-small cell lung cancer, they are poorly understood in ALK-driven anaplastic large cell lymphoma (ALCL). Here, we identify a survival pathway supported by the tumor microenvironment that activates phosphatidylinositol 3-kinase γ (PI3K-γ) signaling through the C-C motif chemokine receptor 7 (CCR7). We found increased PI3K signaling in patients and ALCL cell lines resistant to ALK TKIs. PI3Kγ expression was predictive of a lack of response to ALK TKI in patients with ALCL. Expression of CCR7, PI3Kγ, and PI3Kδ were up-regulated during ALK or STAT3 inhibition or degradation and a constitutively active PI3Kγ isoform cooperated with oncogenic ALK to accelerate lymphomagenesis in mice. In a three-dimensional microfluidic chip, endothelial cells that produce the CCR7 ligands CCL19/CCL21 protected ALCL cells from apoptosis induced by crizotinib. The PI3Kγ/δ inhibitor duvelisib potentiated crizotinib activity against ALCL lines and patient-derived xenografts. Furthermore, genetic deletion of CCR7 blocked the central nervous system dissemination and perivascular growth of ALCL in mice treated with crizotinib. Thus, blockade of PI3Kγ or CCR7 signaling together with ALK TKI treatment reduces primary resistance and the survival of persister lymphoma cells in ALCL.

RET-MAP: An International Multicenter Study on Clinicobiologic Features and Treatment Response in Patients With Lung Cancer Harboring a RET Fusion.

INTRODUCTION: Nearly 1% to 2% of NSCLCs harbor RET fusions. Characterization of this rare population is still incomplete. METHODS: This retrospective multicenter study included patients with any-stage RET positive (RET+) NSCLC from 31 cancer centers. Molecular profiling included DNA/RNA sequencing or fluorescence in situ hybridization analyses. Clinicobiological features and treatment outcomes (per investigator) with surgery, chemotherapy (CT), immune checkpoint blockers (ICBs), CT-ICB, multityrosine kinase inhibitors, and RET inhibitors (RETis) were evaluated. RESULTS: For 218 patients included between February 2012 and April 2022, median age was 63 years, 56% were females, 93% had adenocarcinoma, and 41% were smokers. The most frequent fusion partner was KIF5B (72%). Median tumor mutational burden was 2.5 (range: 1-4) mutations per megabase, and median programmed death-ligand 1 expression was 10% (range: 0%-55%). The most common metastatic sites were the lung (50%), bone (43%), and pleura (40%). Central nervous system metastases were found at diagnosis of advanced NSCLC in 21% of the patients and at last follow-up or death in 31%. Overall response rate and median progression-free survival were 55% and 8.7 months with platinum doublet, 26% and 3.6 months with single-agent CT, 46% and 9.6 months with CT-ICB, 23% and 3.1 months with ICB, 37% and 3 months with multityrosine kinase inhibitor, and 76% and 16.2 months with RETi, respectively. Median overall survival was longer in patients treated with RETi versus no RETi (50.6 mo [37.7-72.1] versus 16.3 mo [12.7-28.8], p < 0.0001). CONCLUSIONS: Patients with RET+ NSCLC have mainly thoracic and bone disease and low tumor mutational burden and programmed death-ligand 1 expression. RETi markedly improved survival, whereas ICB may be active in selected patients.

Strengths and pitfalls of brigatinib in non-small cell lung cancer patients' management.

The treatment landscape of advanced non-small cell lung cancer (NSCLC) patients has dramatically changed over the past 10 years, particularly thanks to the advent and development of several tyrosine kinase inhibitors (TKI) targeting oncogenic drivers. Among them, patients bearing anaplastic lymphoma kinase (ALK) translocations, which are causative of 3-5% of all advanced NSCLC, have seen dramatically improved their clinical outcomes moving life expectancy at 5 years from less than 5% to 50%. In fact, multiple ALK inhibitors (ALKi) entered in the therapeutic algorithm of ALK+ patients, multiplying their treatment opportunities. Remarkably, in the near future we could take advantage of up to different 6 molecules for the first-line approach (crizotinib, ceritinib, alectinib, brigatinib, plus ensartinib and lorlatinib). Among available ALKi, brigatinib, a second-generation (2G) inhibitor, showed notable activity in this setting, also against central nervous system (CNS) disease, and a good safety profile, supporting its approval as upfront treatment based on the ALTA-1L trial results. With a peculiar profile of enzymatic targets, brigatinib represents a valuable opportunity in the ALK targeting journey, albeit having to balance its safety profile. The abundance of therapeutic options for these patients poses nontrivial questions; in absence of direct comparisons of efficacy is not easy to define the best approach and, more compelling, the correct administration sequence in order to give the best therapeutic chances to ALK+ lung cancer patients. In such wide variety of options, we reviewed the preclinical and clinical efficacy data of brigatinib, its pharmacological and safety profile, like also actual and potential future applications in the ALK+ NSCLC scenario. Through a spurious exercise of an indirect comparison with other available 2G ALKi, we tent to summarize the required knowledge to properly choose the best drug at the right time. Furthermore, we reviewed available data on molecular resistance mechanisms and putative therapeutic applications in other contexts, such as ROS1+ NSCLC patients or EGFR+ ones progressing to osimertinib.

The expanding family of c-Met inhibitors in solid tumors: a comparative analysis of their pharmacologic and clinical differences.

c-Met inhibitors are a class of drugs that include nonselective and selective molecules. These drugs can differ in terms of pharmacodynamic and pharmacokinetic properties that may be clinically relevant. c-Met inhibitors with high potency and selectivity may allow achieving optimal c-Met inhibition in c-Met-driven tumors while reducing unwanted off-target toxicities due to activation of multiple kinases. Nonselective drugs can instead be considered in tumors that also recognize other drivers (e.g., ALK, ROS, VEGF). Improved understanding of the clinical pharmacokinetics of c-Met inhibitors can help avoid drug-drug interactions and optimize schedules for continuous in vivo inhibition of c-Met phosphorylation. The current review article provides a detailed overview of the clinical pharmacology of molecules used in c-Met-driven tumors.

HDAC7 promotes NSCLC proliferation and metastasis via stabilization by deubiquitinase USP10 and activation of ß-catenin-FGF18 pathway.

BACKGROUND: Histone deacetylases (HDACs) play crucial roles in cancers, but the role and mechanism of HDAC7 in NSCLC have not been fully understood. METHODS: A total of 319 patients with non-small cell lung cancer (NSCLC) who underwent surgery were enrolled in this study. Immunohistochemistry and Kaplan-Meier survival analysis were performed to investigate the relationship between HDAC7, fibroblast growth factor 18 (FGF18) expression, and clinicopathologic characteristics. Cell functional experiments were implemented both in vivo and in vitro to investigate the effects on NSCLC cell proliferation and metastasis. Recombinant lentivirus-meditated in vivo gene overexpression or knockdown, real-time polymerase chain reaction (PCR), western blotting, and coimmunoprecipitation assays were applied to clarify the underlying molecular mechanism of HDAC7 in promoting NSCLC progression. RESULTS: The elevated expression of HDAC7 or FGF18 was positively correlated with poor prognosis, tumor-node-metastasis (TNM) stage, and tumor differentiation of NSCLC patients. NSCLC patients with co-expressed HDAC7 and FGF18 suffered the worst prognosis. HDAC7 overexpression promoted NSCLC proliferation and metastasis by upregulating FGF18. Conversely, overexpression of FGF18 reversed the attenuated ability in tumor growth and metastasis mediated by downregulating HDAC7. In terms of mechanism, our results suggested that the interaction of HDAC7 with ß-catenin caused decreased ß-catenin acetylation level at Lys49 and decreased phosphorylation level at Ser45. As a consequence, the HDAC7-mediated posttranslational modification of ß-catenin facilitated nuclear transfer and activated FGF18 expression via binding to TCF4. Furthermore, deubiquitinase USP10 interacted with and stabilized HDAC7. The suppression of USP10 significantly accelerated the degradation of HDAC7 and weakened NSCLC growth and migration. CONCLUSIONS: Our findings reveal that HDAC7 promotes NSCLC progression through being stabilized by USP10 and activating the ß-catenin-FGF18 pathway. Targeting this novel pathway may be a promising strategy for further developments in NSCLC therapy.

How far we have come targeting BRAF-mutant non-small cell lung cancer (NSCLC).

The advent of high-throughput sequencing has allowed to profoundly interrogate the molecular landscape of non-small cell lung cancer (NSCLC) in the last years. These findings constitute the opportunity to better stratify these patients in order to address specific treatments to well-defined oncogene-restricted subgroups. Among them, BRAF-mutated lung cancers represent around 4% of NSCLC, thus identifying a clinically relevant population that should be aptly managed. Pivotal phase II trials have demonstrated the efficacy of combinatorial treatment - dabrafenib plus trametinib, targeting both BRAF and MEK - for patients harboring V600E mutations, making this specific BRAF alteration a mandatory requirement in the genetic portrait of advanced non-squamous lung cancer patients. However, around half of BRAF+ NSCLC patients remain orphan of targeted approaches. Here we review the available evidence, mainly from a clinical perspective, of therapeutic strategies for both V600E and non-V600 patients, in terms of small molecule, immune checkpoint inhibitors and forthcoming integrated strategies. Looking at on-going clinical trials, a special attention is dedicated to emergent molecules and combinatorial strategies that not only will improve outcomes of classical V600E, but also will make concrete the chance of tailored treatments for the majority of BRAF-mutated patients.