Immune checkpoint inhibitors in lung cancer: the holy grail has not yet been found…

Prognostic value of KRAS mutations, TP53 mutations and PD-L1 expression among lung adenocarcinomas treated with immunotherapy

AIMS

The aim of this study was to investigate the association between oncogenic alterations and programmed cell death ligand 1 (PD-L1) expression in lung adenocarcinomas, as well as the prognostic value of KRAS and/or TP53 mutations in patients treated with immunotherapy.

METHODS

This study is a retrospective cohort study of 519 patients with lung adenocarcinomas analysed for mutations and PD-L1 expression. Data were collected from electronic pathology record system, next-generation sequencing system, and clinical databases. Association between mutations and PD-L1 expression was investigated, as well as survival statistics of the 65 patients treated with immunotherapy.

RESULTS

41% of the samples contained a KRAS mutation, predominantly together with mutations in TP53 (41%) or STK11 (10%). Higher expression of PD-L1 was seen among patients with KRAS mutations (p=0.002) and EGFR wild type (p=0.006). For patients treated with immunotherapy, there was no statistically significant difference for overall survival (OS) and progression-free survival (PFS) according to KRAS mutation status, TP53 mutation status or PD-L1 expression. The HR for concomitant mutations in TP53 and KRAS was 0.78 (95% CI 0.62 to 0.99) for OS and 0.43 (0.21 to 0.88) for PFS. Furthermore, concomitant TP53 and KRAS mutations predicted a better PFS (p=0.015) and OS (p=0.029) compared with no mutations or a single mutation in either TP53 or KRAS.

CONCLUSION

Mutations in TP53 together with KRAS may serve as a potential biomarker for survival benefits with immunotherapy.

Potential of Black Phosphorus in Immune-Based Therapeutic Strategies

Black phosphorus (BP) consists of phosphorus atoms, an essential element of bone and nucleic acid, which covalently bonds to three adjacent phosphorus atoms to form a puckered bilayer structure. With its anisotropy, band gap, biodegradability, and biocompatibility properties, BP is considered promising for cancer therapy. For example, BP under irradiation can convert near-infrared (NIR) light into heat and reactive oxygen species (ROS) to damage cancer cells, called photothermal therapy (PTT) and photodynamic therapy (PDT). Compared with PTT and PDT, the novel techniques of sonodynamic therapy (SDT) and photoacoustic therapy (PAT) exhibit amplified ROS generation and precise photoacoustic-shockwaves to enhance anticancer effect when BP receives ultrasound or NIR irradiation. Based on the prospective phototherapy, BP with irradiation can cause a “double-kill” to tumor cells, involving tumor-structure damage induced by heat, ROS, and shockwaves and a subsequent anticancer immune response induced by in situ vaccines construction in tumor site, which is referred to as photoimmunotherapy (PIT). In conclusion, BP shows promise in natural antitumor biological activity, biological imaging, drug delivery, PTT/PDT/SDT/PAT/PIT, nanovaccines, nanoadjuvants, and combination immunotherapy regimens.

Clinical outcomes of hyperprogression based on volumetry in non-small cell lung cancer after immune checkpoint inhibitor treatment

BACKGROUND

Hyperprogressive disease (HPD) is a novel pattern of the treatment course after immune checkpoint inhibitor (ICI) therapy in patients with non-small cell lung cancer (NSCLC). This study aimed to investigate the clinical characteristics, outcomes, and associated factors of HPD using a semiautomatic volume measurement.

METHODS

This retrospective study enrolled patients with recurrent and/or metastatic NSCLC treated with ICIs between January 2015 and August 2019 at eight tertiary centers in Korea. HPD was defined according to the tumor growth kinetics and time to treatment failure. Tumor volume was measured using a semiautomatic software.

RESULTS

A total of 219 NSCLC patients with 35 HPD by volumetric measurement (HPDv) (15.9%) were enrolled. The median duration of overall survival (OS) and OS after ICI treatment (ICI-OS) were 34.5 and 18.4 months, respectively. HPDv patients had significantly worse progression-free survival (PFS) than progressive disease patients without HPDv (1.16 vs. 1.82 months, p-value <0.001). ICI-OS did not significantly differ between patients with HPDv and those without HPDv (2.66 vs. 5.4 months, p = 0.105). PD-L1 expression lower than 50%, more than three metastatic sites, neutrophil-to-lymphocyte ratio equal to or higher than 3.3, and hemoglobin level lower than 10 were found to be associated with HPDv.

CONCLUSIONS

There is no standardized definition of HPD. However, defining HPD in NSCLC patients treated with ICI using a semiautomatic volume measurement software is feasible.

Immune escape mechanisms and therapeutic approaches in cancer: the cancer-immunity cycle

The introduction of immune checkpoint inhibitors has changed the therapeutic possibilities for various cancer types. However, despite the success in some entities, a significant fraction of patients does not respond to immune checkpoint inhibitors. A functioning cancer-immunity cycle is needed as the precondition for a clinically meaningful response to immune checkpoint inhibitors. It is assumed that only if each step of the cycle is activated and functioning properly, immune checkpoint inhibitors induce a meaningful immune response. However, an activated cancer-immunity cycle might not be present equally in each patient and cancer type. Ideally, treatment concepts should consider each single step of the cancer-immunity cycle and provide personalized treatment approaches, allowing the adaption to functioning and malfunctioning steps of the individual patient’s specific cancer-immunity cycle. In the following review, we provide an overview of the single steps of the cancer-immunity cycle as well as the impact of malfunctioning steps on the generation of an effective tumor-specific immune response.

Outcomes in 36 Patients with Stage IIIA-N2 Squamous Cell Carcinoma of the Lung Treated with Nab-Paclitaxel Plus Carboplatin as Neoadjuvant Therapy: A Prospective Study from a Single Center

Background

Whether nab-paclitaxel plus carboplatin as neoadjuvant therapy can benefit patients with resectable squamous cell carcinoma of the lung remains unclear. This prospective study aimed to investigate outcomes in patients with stage IIIA-N2 squamous cell carcinoma of the lung treated with nab-paclitaxel plus carboplatin as neoadjuvant therapy.

Material/Methods

Patients with stage IIIA-N2 squamous cell carcinoma of the lung were treated with nab-paclitaxel (100 mg/m², days 1, 8, and 15) and carboplatin (5 mg/(mL·min), day 1) for two 21-day cycles. The patients were followed every 3 months for 2 years and every 6 months after that. The primary endpoint was the downstaging rate. Secondary endpoints included objective response rate (ORR), margin-free (R0) resection, pathologic complete response (pCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

Among the 36 enrolled patients, 33 completed neoadjuvant chemotherapy, and 23 underwent surgery. The preoperative ORR was 50.0% (18/36). R0 resection was achieved in 22 (95.7%) of 23 patients. Major pathologic response and pCR were achieved in 8 (34.8%) and 2 (8.7%) patients, respectively. The overall downstaging rate was 47.8% (11/23). The median follow-up was 39.8 (32.5–41.0) months. For patients who underwent surgery, the median PFS and OS were 31.4 (95%CI: 10.4-not reached (NR)) and 45.0 (95%CI: 22.6-NR) months, respectively. The most common adverse events were neutropenia, anemia, and leukopenia.

Conclusions

This study preliminarily indicated a favorable effect of nab-paclitaxel plus carboplatin as neoadjuvant therapy without significant adverse events for stage IIIA-N2 squamous cell carcinoma of the lung. Future randomized controlled trials are needed to verify these results.

Tumor necrosis factor in lung cancer: Complex roles in biology and resistance to treatment

Tumor necrosis factor (TNF) and its receptors are widely expressed in non-small cell lung cancer (NSCLC). TNF has an established role in inflammation and also plays a key role in inflammation-induced cancer. TNF can induce cell death in cancer cells and has been used as a treatment in certain types of cancer. However, TNF is likely to play an oncogenic role in multiple types of cancer, including NSCLC. TNF is a key activator of the transcription factor NF-κB. NF-κB, in turn, is a key effector of TNF in inflammation-induced cancer. Data from The Cancer Genome Atlas database suggest that TNF could be a biomarker in NSCLC and indicate a complex role for TNF and its receptors in NSCLC. Recent studies have reported that TNF is rapidly upregulated in NSCLC in response to targeted treatment with epidermal growth factor receptor (EGFR) inhibition, and this upregulation leads to NF-κB activation. The TNF upregulation and consequent NF-κB activation play a key role in mediating both primary and secondary resistance to EGFR inhibition in NSCLC, and a combined inhibition of EGFR and TNF can overcome therapeutic resistance in experimental models. TNF may mediate the toxic side effects of immunotherapy and may also modulate resistance to immune checkpoint inhibitors. Drugs inhibiting TNF are widely used for the treatment of various inflammatory and rheumatologic diseases and could be quite useful in combination with targeted therapy of NSCLC and other cancers.

The current landscape of single-cell transcriptomics for cancer immunotherapy

Immunotherapies such as immune checkpoint blockade and adoptive cell transfer have revolutionized cancer treatment, but further progress is hindered by our limited understanding of tumor resistance mechanisms. Emerging technologies now enable the study of tumors at the single-cell level, providing unprecedented high-resolution insights into the genetic makeup of the tumor microenvironment and immune system that bulk genomics cannot fully capture. Here, we highlight the recent key findings of the use of single-cell RNA sequencing to deconvolute heterogeneous tumors and immune populations during immunotherapy. Single-cell RNA sequencing has identified new crucial factors and cellular subpopulations that either promote tumor progression or leave tumors vulnerable to immunotherapy. We anticipate that the strategic use of single-cell analytics will promote the development of the next generation of successful, rationally designed immunotherapeutics.

The risk of diarrhea and colitis in patients with lung cancer treated with immune checkpoint inhibitors: a systematic review and meta-analysis

Background

Immune checkpoint inhibitors (icis), including inhibitors of PD-1, PD-L1, and ctla-4, are relatively novel therapies for lung cancer, although their use might be limited by gastrointestinal toxicity. The aim of the present study was to determine the risk of diarrhea and colitis associated with icis in lung cancer and the rates of discontinuation because of those toxicities.

Methods

Electronic databases were searched for prospective trials reporting the risk of diarrhea and colitis in patients with lung cancer treated with PD-1, PD-L1, and ctla-4 inhibitors. The incidences of diarrhea and colitis and their grades were assessed clinically using standardized reporting criteria. Pooled incidence and weighted relative risk estimates for diarrhea and colitis with 95% confidence intervals (cis) were estimated using a random effects model. The incidence of discontinuations for gi toxicity was also calculated.

Results

Twenty-seven studies were included: sixteen studies with PD-1 inhibitors, nine studies with PD-L1 inhibitors, and four studies combining PD-based strategies with ctla-4 inhibitors. The incidence of all-grade diarrhea was 9.1% (95% ci: 7.8% to 10.5%) for anti-PD-1 therapy and 11.0% (95% ci: 7.5% to 14.5%) for anti-PD-L1 therapy. The incidence of all-grade colitis was 0.9% (95% ci: 0.4% to 1.3%) for anti-PD-1 therapy and 0.4% (95% ci: 0.0% to 0.8%) for anti-PD-L1 therapy. The relative risk for all-grade diarrhea was higher with combination anti-PD-1 and anti-ctla-4 than with anti-PD-1 monotherapy (relative risk: 1.61; 95% ci: 1.14 to 2.29). Anti-PD-1 therapy was discontinued in 4.1% of patients with diarrhea (95% ci: 0.7% to 7.4%) and in 35.7% of those with colitis (95% ci: 0.0% to 81.1%); combination therapy was discontinued in 10.1% of patients with diarrhea (95% ci: 4.8% to 15.4%) and in 39.9% of those with colitis (95% ci: 3.9% to 75.9%).

Conclusions

Diarrhea is a relatively frequently encountered gi toxicity when ici therapy is used in lung cancer treatment. Colitis is less frequently encountered, although when it does occur, it often results in therapy discontinuation.

Nab-paclitaxel in combination with Bevacizumab in patients with non-squamous non-small cell lung cancer after failure of at least one prior systemic regimen

Background: Most patients with non-small cell lung cancer (NSCLC) experience disease progression after first-line treatment. The efficacy and safety of the nab-paclitaxel (nab-PTX) and bevacizumab combination as the second or further line of treatment in patients with advanced NSCLC have not been reported yet. Objective: To evaluate the efficacy and safety of the nab-PTX and bevacizumab combination in patients with advanced non-squamous (NSQ) NSCLC after failure of at least one prior systemic regimen. Methods: Patients with advanced (stage IV) NSQ NSCLC who received the nab-PTX and bevacizumab combination as the second or further line treatment between February 2012 and December 2018 at the Cancer Hospital of the Chinese Academy of Medical Sciences (Beijing, China) were included in this retrospective study. The main outcomes included the objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety. Results: Thirty-four patients received 1-27 cycles (median, four cycles) of treatment; 67.6% (23/34) patients had undergone at least two lines of previous treatment. The ORR and disease control rates were 26.5% (9/34) and 82.4% (28/34), respectively. The median PFS and OS were 6.0 (95% CI=2.9-7.2) and 11.0 (95% CI=7.8-18.7) months, respectively. The multivariable analyses indicated that the combined use of other drugs and pleural metastasis were respectively associated with better PFS (hazard ratio=0.354, 95% CI=0.134-0.935, P=0.036) and OS (hazard ratio=0.540, 95% CI=0.118-0.980, P=0.046). The most frequent grade 3-4 adverse events (AEs) were neutropenia 20.6% (7/34), leukopenia 8.8% (3/34), and anemia 5.9% (2/34). No grade 5 AE occurred. Conclusion: Combined nab-PTX and bevacizumab might be an effective treatment regimen for patients with advanced NSQ NSCLC after failure of at least one prior systemic regimen, but studies have to validate those findings.

A Greedy Algorithm-Based Stem Cell LncRNA Signature Identifies a Novel Subgroup of Lung Adenocarcinoma Patients With Poor Prognosis

Cancer stem cells play an essential role in therapy response and aggressiveness of various cancers, including lung adenocarcinoma (LUAD). Interestingly it also shares many features of embryonic stem cells (ESCs). Recently, long non-coding RNAs (lncRNAs) have emerged as a critical regulator of cell physiology. Here, we used expression data of ESCs, LUAD, and normal lung to identify 198 long non-coding hESC-associated lncRNAs (hESC-lncRNAs). Intriguingly, K-means clustering of hESC-associated lncRNAs identified a subgroup of LUAD patients [undifferentiated LUAD (uLUAD)] with high stem cell-like characteristic, decreased differentiation genes expression, and poor survival. We also observed that the uLUAD patients had overexpression of proteins associated with cell proliferation. Interestingly, uLUAD patients were highly enriched with the stemness-related gene sets, and had higher mutation load. A notable result observed was high infiltration of T cells and a higher level of neopeptides in uLUAD patients, making these patients an optimal candidate for immunotherapy. Further, feature selection using greedy algorithm identified 17-hESC-lncRNAs signature, which showed significant consistency with 198 hESC-lncRNAs-based classification, and identified a group of patients with high stem cell-like characteristic in the 10 most common cancer types and CCLE cell lines. These results suggest the conventional role of hESC-lncRNAs in stem cell biology. In summary, we identified a novel subgroup of LUAD patients (uLUAD) using a set of hESC-lncRNAs. The uLUAD patients had high stem cell-like characteristic and reduced survival rate and may be referred for immunotherapy. Furthermore, our analysis also showed the importance of lncRNAs in cancer and cancer stem cells.

Anti-angiogenic agents in the age of resistance to immune checkpoint inhibitors: Do they have a role in non-oncogene-addicted non-small cell lung cancer?

The introduction of licensed front-line immunotherapies has heralded a new era for the treatment of non-oncogene-addicted, advanced non-small cell lung cancer (NSCLC). Yet as with all evolutions in clinical management, changes in practice can outpace the availability of the clinical evidence needed to inform subsequent therapeutic decision making. At the time of writing, there is limited available evidence on the optimum therapeutic options after progression on immunotherapy. Further research is needed to define mechanisms of immunotherapy resistance in patients with advanced NSCLC, and to understand the implications for subsequent treatment response. Pending the availability of robust clinical data and proven therapeutic options to underpin an optimized therapeutic pathway after progression on immunotherapy, attention must turn to the potential utility of currently licensed agents and any available supporting clinical data in this setting. Within this context we review the mechanistic arguments and supporting evidence for the use of anti-angiogenic agents as a means of targeting immunosuppression within the tumor microenvironment. We consider whether VEGF inhibition may help to normalize the tumor vasculature and to address immunosuppression - reinstating, and potentially enhancing, the effect of subsequent therapies. We also highlight evidence needs and signpost ongoing trials that should enable current clinical opinion in this area to be replaced by robust, evidence-based guidance.

EGFR inhibition triggers an adaptive response by co-opting antiviral signaling pathways in lung cancer

EGFR inhibition is an effective treatment in the minority of non-small cell lung cancer (NSCLC) cases harboring EGFR-activating mutations, but not in EGFR wild type (EGFRwt) tumors. Here, we demonstrate that EGFR inhibition triggers an antiviral defense pathway in NSCLC. Inhibiting mutant EGFR triggers Type I IFN-I upregulation via a RIG-I-TBK1-IRF3 pathway. The ubiquitin ligase TRIM32 associates with TBK1 upon EGFR inhibition, and is required for K63-linked ubiquitination and TBK1 activation. Inhibiting EGFRwt upregulates interferons via an NF-κB-dependent pathway. Inhibition of IFN signaling enhances EGFR-TKI sensitivity in EGFR mutant NSCLC and renders EGFRwt/KRAS mutant NSCLC sensitive to EGFR inhibition in xenograft and immunocompetent mouse models. Furthermore, NSCLC tumors with decreased IFN-I expression are more responsive to EGFR TKI treatment. We propose that IFN-I signaling is a major determinant of EGFR-TKI sensitivity in NSCLC and that a combination of EGFR TKI plus IFN-neutralizing antibody could be useful in most NSCLC patients.

miR-181a/b therapy in lung cancer: reality or myth?

Despite substantial progress in oncology, lung cancer remains the number one malignancy in terms of both incidence and mortality rates, and there thus remains an urgent need for new therapeutic alternatives. MicroRNA (miRNA) have an important role in cancer initiation and progression due to their capacity to interfere with transcriptional signaling and regulate key cellular processes. miR-181a and miR-181b (miR-181a/b), which are located on chromosomes 1 and 9, are pathologically expressed in the tumor tissue and plasma of patients diagnosed with lung cancer. The miR-181a/b regulatory mechanisms are sophisticated and are directly related to different target genes. In recent years, an ever-increasing number of studies have focused on the biological relevance of miR-181a/b in key cellular processes. In this paper, we aim to discuss the challenging experimental data related to miR-181a/b and their potential use for the development of new therapeutic approaches in lung cancer. We will further present the ongoing issues regarding the regulation of their multiple target genes, and their potential use as biomarkers and therapeutic targets in this deadly malignancy.

Current views on molecularly targeted therapy for lung cancer - a review of literature from the last five years

Lung cancer is the main cause of cancer-related deaths in Poland. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are a new group of agents for non-small-cell lung cancer (NSCLC) patients. Determining the predictive value of activating mutations in the EGFR and ROS-1 genes and ALK rearrangement in non-small-cell lung cancer has enabled the identification of patients likely to achieve true clinical benefits. EGFR-TKIs may produce objective response in more than 60% of patients and prolong progression-free survival to 10 months in mutation-positive patients. No improvement of overall survival was shown in randomized trials. The era of immunotherapy implementing PD-1 and PD-L1 inhibitors has changed the face of lung cancer therapy. We aimed to review the literature on the use of EGFR-TKIs and immunotherapeutic agents for NSCLC patients.

Randomized, Double-Blind, Placebo-Controlled, Multicenter Phase II Study of Fruquintinib After Two Prior Chemotherapy Regimens in Chinese Patients With Advanced Nonsquamous Non‒Small-Cell Lung Cancer

Purpose Patients with advanced non‒small-cell lung cancer (NSCLC) who fail two lines of chemotherapy have unmet medical needs. The kinase inhibitor fruquintinib selectively targets vascular endothelial growth factor receptors and, hence, tumor angiogenesis and lymphogenesis. This randomized, double-blind, placebo-controlled, multicenter phase II trial evaluated the efficacy and safety of fruquintinib in patients with advanced nonsquamous NSCLC who experienced disease progression after second-line chemotherapy. Patients and Methods Eligible patients were randomly assigned (two to one; stratified by epidermal growth factor receptor status) to receive fruquintinib or placebo, both in combination with best supportive care. Oral fruquintinib (5 mg once daily) was given in 4-week cycles of 3 weeks of treatment followed by 1 week off. Tumor response was assessed using Response Evaluation Criteria in Solid Tumors version 1.1. The primary end point was progression-free survival (PFS) evaluated by a blinded image central review (BICR) committee. Secondary end points included investigator-evaluated PFS, objective response rate, disease control rate, overall survival, and safety. Results Ninety-one patients from 12 hospitals received treatment with fruquintinib (n = 61) or placebo (n = 30). Median PFS was 3.8 months with fruquintinib by both BICR and investigators' evaluations (hazard ratio by BICR, 0.34; 95% CI, 0.20 to 0.57; P < .001). Three- and 6-month survival rates were 90.2% and 67.2% in the fruquintinib group and 73.3% and 58.8% in the placebo group, respectively. The objective response rate and disease control rate were 13.1% and 60.7% with fruquintinib, compared with 0% and 13.3% with placebo ( P = .041 and < .001), respectively. The most common treatment-emergent adverse events with fruquintinib (≥ grade 3) were hypertension (8.2%), hand-foot syndrome (4.9%), and proteinuria (4.9%). Conclusion Third- and fourth-line fruquintinib for advanced NSCLC was superior to placebo and had an acceptable safety profile.