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Li et al. present data from a randomized frontline phase II trial in HER2+ gastroesophageal cancers exploring dual targeting of HER2 with HLX22 (a novel HER2-specific antibody) with HLX02 (a trastuzumab biosimilar) and capecitabine/oxaliplatin chemotherapy. While the objective response and progression-free survival are encouraging, the future development of the combination in a crowded HER2 space remains unclear.

Despite the success of PD-1 blockade in melanoma and other cancers, effective treatment strategies to overcome resistance to cancer immunotherapy are lacking1,2. Here we identify the innate immune kinase TANK-binding kinase 1 (TBK1)3as a candidate immune-evasion gene in a pooled genetic screen4. Using a suite of genetic and pharmacological tools across multiple experimental model systems, we confirm a role for TBK1as an immune-evasion gene. Targeting TBK1 enhances responses to PD-1 blockade by decreasing the cytotoxicity threshold to effector cytokines (TNF and IFNγ). TBK1 inhibition in combination with PD-1 blockade also demonstrated efficacy using patient-derived tumour models, with concordant findings in matched patient-derived organotypic tumour spheroids and matched patient-derived organoids. Tumour cells lacking TBK1 are primed to undergo RIPK- and caspase-dependent cell death in response to TNF and IFNγ in a JAK–STAT-dependent manner. Taken together, our results demonstrate that targeting TBK1 is an effective strategy to overcome resistance to cancer immunotherapy.

While BRAF inhibitor combinations with EGFR and/or MEK inhibitors have improved clinical efficacy in BRAFV600Ecolorectal cancer (CRC), response rates remain low and lack durability. Preclinical data suggest that BRAF/MAPK pathway inhibition may augment the tumor immune response. We performed a proof-of-concept single-arm phase 2 clinical trial of combined PD-1, BRAF and MEK inhibition with sparatlizumab (PDR001), dabrafenib and trametinib in 37 patients with BRAFV600ECRC. The primary end point was overall response rate, and the secondary end points were progression-free survival, disease control rate, duration of response and overall survival. The study met its primary end point with a confirmed response rate (24.3% in all patients; 25% in microsatellite stable patients) and durability that were favorable relative to historical controls of BRAF-targeted combinations alone. Single-cell RNA sequencing of 23 paired pretreatment and day 15 on-treatment tumor biopsies revealed greater induction of tumor cell-intrinsic immune programs and more complete MAPK inhibition in patients with better clinical outcome. Immune program induction in matched patient-derived organoids correlated with the degree of MAPK inhibition. These data suggest a potential tumor cell-intrinsic mechanism of cooperativity between MAPK inhibition and immune response, warranting further clinical evaluation of optimized targeted and immune combinations in CRC. ClinicalTrials.gov registration: NCT03668431.

ABSTRACTIntroductionThe Wnt/beta-catenin pathway is a complex signaling pathway known to be dysregulated in several cancers; Dickkopf-1 (Dkk1) is an inhibitor of canonical Wnt signaling via negative feedback. Elevated Dkk1 is associated with a poor prognosis in several cancers, including gynecologic and gastroesophageal malignancies. This review focuses on the potential therapeutic benefit of targeting Dkk1 with the IgG4 monoclonal antibody, DKN-01.Areas coveredWe highlight current treatment approaches for advanced gynecologic and esophageal malignancies highlighting the need for more effective therapies, specifically improved immune-modulating agents and combinations. Our discussion of DKN-01 addresses the rationale for targeting Dkk1, available safety, pharmacokinetic and efficacy data.Expert opinionDKN-01 presents an interesting therapeutic consideration in advanced gynecologic and gastroesophageal malignancies. It has been especially promising in patients with high-Dkk1-expressing tumors or known Wnt mutations. We postulate that the complementary mechanisms, limited adverse effects and emerging biomarker data position DKN-01 as a promising agent for combination therapy in patients with advanced malignancies. Specifically, we believe this occurs through an immuno-modulatory effect, primarily acting through the innate arm of the immune system. This highlights the possibility for addressing innate immune resistance and expanding the portion of patients who may benefit, possibly in a biomarker-selected manner.

ObjectiveWhile oesophageal squamous cell carcinoma remains infrequent in Western populations, the incidence of oesophageal adenocarcinoma (EAC) has increased sixfold to eightfold over the past four decades. We aimed to characterise oesophageal cancer-specific and subtypes-specific gene regulation patterns and their upstream transcription factors (TFs). DesignTo identify regulatory elements, we profiled fresh-frozen oesophageal normal samples, tumours and cell lines with chromatin immunoprecipitation sequencing (ChIP-Seq). Mathematical modelling was performed to establish (super)-enhancers landscapes and interconnected transcriptional circuitry formed by master TFs. Coregulation and cooperation between master TFs were investigated by ChIP-Seq, circularised chromosome conformation capture sequencing and luciferase assay. Biological functions of candidate factors were evaluated both in vitro and in vivo.ResultsWe found widespread and pervasive alterations of the (super)-enhancer reservoir in both subtypes of oesophageal cancer, leading to transcriptional activation of a myriad of novel oncogenes and signalling pathways, some of which may be exploited pharmacologically (eg, leukemia inhibitory factor (LIF) pathway). Focusing on EAC, we bioinformatically reconstructed and functionally validated an interconnected circuitry formed by four master TFs—ELF3, KLF5, GATA6 and EHF—which promoted each other’s expression by interacting with each super-enhancer. Downstream, these master TFs occupied almost all EAC super-enhancers and cooperatively orchestrated EAC transcriptome. Each TF within the transcriptional circuitry was highly and specifically expressed in EAC and functionally promoted EAC cell proliferation and survival.ConclusionsBy establishing cancer-specific and subtype-specific features of the EAC epigenome, our findings promise to transform understanding of the transcriptional dysregulation and addiction of EAC, while providing molecular clues to develop novel therapeutic modalities against this malignancy.

Tumor resistance to EGFR tyrosine kinase inhibitors (TKIs) occurs invariably, and receptor tyrosine kinase (RTK) fusions have emerged as rare but actionable resistance mechanisms. In 2015, the detection of RTK fusions as acquired resistance (AR) in two cases was first reported. Subsequently, a survey of FGFR3-TACC3fusion and other RTK fusions from a large commercial genomic sequencing company database was published, followed by large-scale clinical trials of EGFR TKIs demonstrating the emergence of RTK fusions in AR. However, detailed examination of the AR RTK fusion landscape in non-small-cell lung cancer is lacking. Hence, we conducted a comprehensive review to categorize these fusion events by the generation of EGFR TKIs, the specific RTK fusions and their fusion partners, the founder EGFRmutations, and their methods of detection. To support the actionability and clinical significance of AR RTK fusions we present all available data demonstrating clinical benefit of concurrent dual blockade of the AR RTK fusion and the original EGFRmutation.

We analyzed a large set of EGFR-mutated (EGFR+) NSCLC to identify and characterize cases with co-occurring kinase fusions as potential resistance mechanisms to EGFR tyrosine kinase inhibitors (TKIs).

Erb-b2 receptor tyrosine kinase (HER2) transmembrane domain (TMD) mutations (HER2V659E, HER2G660D) have previously been identified in lung adenocarcinomas, but their frequency and clinical significance is unknown.

METproto-oncogene, receptor tyrosine kinase gene exon 14 skipping (METex14) alterations represent a unique subset of oncogenic drivers in NSCLC. Preliminary clinical activity of crizotinib against METex14-positive NSCLC has been reported. The full spectrum of resistance mechanisms to crizotinib in METex14-positive NSCLC remains to be identified.

A significant portion of NSCLCs with MET proto-oncogene, receptor tyrosine kinase gene (MET) exon 14 skipping alterations are sensitive to small-molecule mesenchymal-epithelial transition tyrosine kinase inhibitors. However, the incidence and management of brain metastases in this molecular subset is unknown and represents an unmet clinical need.

Introduction:Epithelial ovarian cancer (EOC) is the second most common gynecologic malignancy and the leading cause of death from gynecologic cancer in the USA. EOC is an exquisitely chemo-sensitive disease with response rates of over 75% in the upfront setting. Despite this, due to high rates of recurrence and development of chemo-resistance, the overall survival of EOC remains about 25%. Thus, there is a great need for new therapeutic approaches to render more durable responses. Based on preclinical and early phase clinical studies, key targeted pathways include targets that drive angiogenesis and chemo-resistance. Receptor tyrosine kinases and non-receptor tyrosine kinases play important roles in these processes and several small molecule tyrosine kinase inhibitors (TKIs) are in clinical development.Areas covered:This review summarizes clinical rationale, mechanisms of action and clinical data for the TKIs under evaluation in the Phase III setting for EOC.Expert opinion:Despite reasonable preclinical activity, small molecule TKIs are unlikely to improve patient survival as single agent therapies in an unselected EOC population. Incorporation of tissue evaluation during ongoing clinical trials is required to identify molecularly defined groups that respond to single agents and direct rational combination strategies based on mechanisms of resistance to improve outcomes in EOC.

•NUT carcinoma is a rare but aggressive solid tumor that can be diagnosed by presence of the BRD4-NUT fusion.•This series presents 31 cases of solid tumors that harbor BRD4-NUT but often carry other diagnoses such NSCLCNOS and NSCLC-SCC.•Despite lack of PD-L1 expression and a low tumor mutational burden, two index cases responded to either nivolumab or atezolizumab+chemotherapy with partial response or better with 4–5 month duration of response.•The unexpected response to checkpoint inhibitors could be explained by a very high affinity of the fusion peptide at the junction of BRD4 and NUT to the MHC complex as recently suggested for an exceptional response to an immune checkpoint inhibitor in a fusion bearing low TMB, low PD-L1 expression head and neck carcinoma.

This is the case report of a 61-year-old woman who presented with progressive diplopia and ataxia. Her cerebrospinal fluid revealed high titers of anti-Yo (PCA-1) antibody and a magnetic resonance imaging with contrast showed cerebellar degeneration. Extensive imaging workup was negative for malignancy and she was otherwise asymptomatic. Given the association between anti-Yo antibodies and gynecologic malignancies, she underwent a bilateral salpingo-oophorectomy and cancer staging. Extensive section of the fimbriated end of the fallopian tube revealed a stage 1, microscopic serous adenocarcinoma. After surgery, her anti-YO titers fell and plans were made for adjuvant chemotherapy. Her neurologic symptoms are not expected to substantially improve, illustrating the urgent need for early surgical investigation in cases of paraneoplastic syndrome, even in the absence of imaging evidence of a lesion.