dSCOPE: a software to detect sequences critical for liquid-liquid phase separation.

Membrane-based cells are the fundamental structural and functional units of organisms, while evidences demonstrate that liquid-liquid phase separation (LLPS) is associated with the formation of membraneless organelles, such as P-bodies, nucleoli and stress granules. Many studies have been undertaken to explore the functions of protein phase separation (PS), but these studies lacked an effective tool to identify the sequence segments that critical for LLPS. In this study, we presented a novel software called dSCOPE (http://dscope.omicsbio.info) to predict the PS-driving regions. To develop the predictor, we curated experimentally identified sequence segments that can drive LLPS from published literature. Then sliding sequence window based physiological, biochemical, structural and coding features were integrated by random forest algorithm to perform prediction. Through rigorous evaluation, dSCOPE was demonstrated to achieve satisfactory performance. Furthermore, large-scale analysis of human proteome based on dSCOPE showed that the predicted PS-driving regions enriched various protein post-translational modifications and cancer mutations, and the proteins which contain predicted PS-driving regions enriched critical cellular signaling pathways. Taken together, dSCOPE precisely predicted the protein sequence segments critical for LLPS, with various helpful information visualized in the webserver to facilitate LLPS-related research.

Advances in detecting N6-methyladenosine modification in circRNAs.

Circular RNAs (circRNAs) are a class of noncoding RNAs with covalently single-stranded closed loop structures derived from back-splicing event of linear precursor mRNAs (pre-mRNAs). N6-methyladenosine (m6A), the most abundant epigenetic modification in eukaryotic RNAs, has been shown to play a crucial role in regulating the fate and biological function of circRNAs, and thus affecting various physiological and pathological processes. Accurate identification of m6A modification in circRNAs is an essential step to fully elucidate the crosstalk between m6A and circRNAs. In recent years, the rapid development of high-throughput sequencing technology and bioinformatic methodology has propelled the establishment of a multitude of approaches to detect circRNAs and m6A modification, including in vitro-based and in silico methods. Based on this, the research community has started on a new journey to develop methods for identification of m6A modification in circRNAs. In this review, we provide a comprehensive review and evaluation of the existing methods responsible for detecting circRNAs, m6A modification, and especially, m6A modification in circRNAs, which mainly focused on those developed based on high-throughput technologies and methodology of bioinformatics. This handy reference can help researchers figure out towards which direction this field will go.

Comparison of response evaluation criteria in solid tumors and tumor regression grade in evaluating the effect of preoperative systemic therapy of gastric cancer.

BACKGROUND: Both Response Evaluation Criteria in Solid Tumors (RECIST) and tumor regression grade (TRG) play key roles in evaluating tumor response. We analyzed the consistency of TRG and RECIST 1.1 for gastric cancer (GC) patients and compared their prognostic values. METHODS: Patients with GC who received preoperative chemotherapy or chemoimmunotherapy and had records of TRG from December 2013 to October 2021 were enrolled retrospectively. TRG 0-1 and 2-3 are considered as corresponding to complete response (CR)/partial response (PR) and stable disease (SD)/progress disease (PD) in RECIST 1.1, respectively. The primary endpoints were disease-free survival (DFS) and overall survival (OS). The consistency of RECIST and TRG was examined by kappa statistics. Survival analysis was performed using the Kaplan Meier method. RESULT: One hundred fifty seven GC patients were enrolled, including 125 with preoperative chemotherapy and 32 with chemoimmunotherapy. Among them, 56 patients had measurable lesions. Only 19.6% (11/56) of the patients had consistent results between RECIST 1.1 and TRG. TRG was correlated with both OS and DFS (P = 0.02 and 0.03, respectively) while response according to RECIST1.1 was not (P = 0.86 and 0.23, respectively). The median DFS had not reached in the TRG 0-1 group and was 16.13 months in TRG 2-3 group. TRG 2-3 was associated with young age and peritoneal or liver metastasis. Besides, preoperative chemoimmunotherapy had a significantly higher pCR rate than chemotherapy alone (34.4% vs 8.0%, P < 0.001). CONCLUSION: TRG was in poor agreement with RECIST 1.1. TRG was better than RECIST 1.1 in predicting DFS and OS for GC patients who received preoperative therapy.

Optimal prophylaxis of chemotherapy-induced nausea and vomiting for moderately emetogenic chemotherapy: a meta-analysis.

AIM: We compare neurokinin-1 receptor antagonist (NK-1RA)-based triple regimen and conventional duplex regimen for antiemetic efficacy for patients with moderately emetogenic chemotherapy (MEC). Patients & methods: Pooled risk ratios (RRs) were used to evaluate the complete response and no significant nausea. The results were separately analyzed for pure MEC regimens, carboplatin-based regimens and oxaliplatin-based regimens. RESULTS: Ten trials focused on MEC involving 2928 cancer patients using NK-1RA triple regimens or conventional duplex regimen were included. NK-1RA-based triple regimen showed significant better complete responses in overall (RR: 1.14; 95% CI: 1.05-1.24), acute (RR: 1.02; 95% CI: 1.00-1.04) and delayed (RR: 1.13; 95% CI: 1.04-1.23) phase compared with duplex regimen in patients with MEC. Similar results were found for no significant nausea. Subgroup analyses showed that triple regimen showed superior antiemetic efficacy significantly in patients with carboplatin-based chemotherapy, instead of oxaliplatin-based chemotherapy. CONCLUSION: NK-1RA is recommended to use in carboplatin-based chemotherapy, not oxaliplatin-based chemotherapy.

Long Noncoding RNA SNHG5 Induces the NF-κB Pathway by Regulating miR-181c-5p/CBX4 Axis to Promote the Progression of Non-Small Cell Lung Cancer.

OBJECTIVE: Explorations have been progressing in decoding the mechanism of non-small cell lung cancer (NSCLC). However, long noncoding RNA small nucleolar RNA host gene 5/microRNA-181c-5p/chromobox protein 4 (SNHG5/miR-181c-5p/CBX4) axis-oriented mechanisms in NSCLC is still in infancy. Therein, this study is proposed to probe this axis in NSCLC progression. METHODS: Samples of 86 NSCLC patients were collected and SNHG5, miR-181c-5p and CBX4 expression was detected in NSCLC tissues and cells. NSCLC cells were transfected with plasmids to change SNHG5, miR-181c-5p or CBX4 expression, after which cell functions and phosphorylated (p)-nuclear factor (NF)-κB protein expression were evaluated. The relationships among SNHG5, miR-181c-5p and CBX4 were validated. Tumor xenografts were implemented to verify the roles of SNHG5, miR-181c-5p and CBX4 in tumor growth. RESULTS: Low miR-181c-5p and high SNHG5 and CBX4 levels were found in NSCLC tissues and cells. Restoration of miR-181c-5p or knockdown of SNHG5 or CBX4 restrained NSCLC cell progression and inactivated the NF-κB pathway. Upregulated CBX4 abolished the effects of miR-181c-5p on reducing NSCLC cell progression. SNHG5 regulated the interaction between miR-181c-5p and CBX4. In vivo, restoration of miR-181c-5p or knockdown of SNHG5 or CBX4 retarded the tumor growth. CONCLUSION: This study has delineated that SNHG5 induces the NF-κB pathway by regulating the miR-181c-5p/CBX4 axis to promote NSCLC progression, which may pave a novel path for NSCLC treatment.

Effect of Dexmedetomidine-Assisted Intravenous Anesthesia on Gastrointestinal Motility in Colon Cancer Patients After Open Colectomy.

Background: To explore the effect of dexmedetomidine (Dex)-assisted intravenous anesthesia on gastrointestinal motility in patients with colon cancer (CC) after open colectomy. Methods: A total of 102 patients with CC, undergoing open colectomy in our hospital from January 2018 to January 2020, were selected and randomly divided into an observation group (n = 51) and a control group (n = 51). The patients in the control group received a routine combination of intravenous and inhalation anesthesia (CIIA), while those in the observation group received a Dex-assisted CIIA. The systolic blood pressure (SBP), the diastolic blood pressure (DBP), heart rate (HR), and the mean arterial pressure (MAP) were compared at different time points between the two groups. In addition, the intraoperative general conditions, the dosage of anesthetics, and the recovery of gastrointestinal functions were also compared between the two groups. Moreover, before operation and at 24 h after operation, the levels of serum gastrin (GAS) and plasma motilin (MTL) were detected by radioimmunoassay, and the level of plasma cholecystokinin (CCK) was detected by an enzyme-linked immunosorbent assay. The incidence of gastrointestinal complications was recorded in both groups. Results: At T1-T3, the HR, SBP, DBP, and MAP levels were lower in both groups than those at T0. In addition, they were also lower in the observation group than those in the control group, showing significant differences (p < 0.05). The dosage of propofol and remifentanil in the observation group was lower than that in the control group, and there was a significant difference (p < 0.05). In the observation group, the postoperative first exhaust time, first defecation time, first ambulation time, and first feeding time were all earlier than those in the control group with significant differences (p < 0.05). After the operation, the observation group had higher levels of GAS and MTL but a lower level of CCK than the control group, and the differences were significant (p < 0.05). The incidence rate of gastrointestinal complications in the observation group (7.04%) was lower than that in the control group (19.61%), and there was a significant difference (χ2 = 4.346, p < 0.05). Conclusions: Dex-assisted intravenous anesthesia can facilitate the recovery of gastrointestinal motility, can regulate the levels of gastrointestinal hormones, and can stabilize the levels of hemodynamic indexes in patients with CC after open colectomy.

Efficacy of EP Chemotherapy Followed by IP Chemotherapy Combined with Radiotherapy in the Treatment of Extensive-Stage Small-Cell Lung Cancer.

PURPOSE: To explore the efficacy and safety of etoposide + cisplatin (EP) and irinotecan + cisplatin (IP) sequential chemotherapy combined with radiotherapy in the treatment of extensive-stage small-cell lung cancer (SCLC). METHODS: A total of 108 patients with extensive-stage SCLC were divided into the EP+IP group (n=54, sequential IP chemotherapy), and the EP group (n=54, EP chemotherapy). The changes in the level of serum tumor markers and the number of circulating tumor cells (CTCs) in the peripheral blood were compared between the two groups of patients before and after treatment. The patients were followed up to record the survival status and tumor progression. RESULTS: The overall effective rate for bone metastases in the EP+IP group was significantly higher than that in the EP group. The EP+IP group displayed significantly lower levels of serum VEGF, Ki-67 and peripheral blood CTCs than the EP group. In addition, the follow-up results manifested that the median overall survival (OS) in the EP+IP group and the EP group were 16.2 months and 12.7 months, respectively, and the median progression-free survival (PFS) was 8.4 months and 5.9 months, respectively. The 2-year OS was 13.0% and 7.4%, respectively. Furthermore, the log-rank test illustrated that the OS and PFS in the EP+IP group were significantly superior to those in the EP group. CONCLUSIONS: EP and IP sequential chemotherapy combined with radiotherapy is more effective than EP chemotherapy combined with radiotherapy in the treatment of extensive-stage SCLC. The former can markedly reduce the levels of serum tumor markers and peripheral blood CTCs, increase the long-term survival of patients and reduce the occurrence of blood-related adverse reactions.

JTC-801 alleviates mechanical allodynia in paclitaxel-induced neuropathic pain through the PI3K/Akt pathway.

Chemotherapy-induced peripheral neuropathy is a serious adverse effect of chemotherapeutic agents such as paclitaxel. JTC-801, a nociceptin/orphanin FQ opioid peptide (NOP) receptor antagonist, has been reported to attenuate neuropathic pain in several pain models. However, the therapeutic significance and function of JTC-801 in chemotherapy-induced peripheral neuropathy remain unclear. In this study, we determined the effect of JTC-801 on neuropathic pain induced by paclitaxel, and we explored the potential mechanism in the dorsal root ganglion (DRG). The behavioral test showed that single or multiple systemic administrations of JTC-801 significantly alleviated mechanical allodynia in paclitaxel-treated rats. Using Western blot analysis and immunohistochemistry, we found that paclitaxel increased the expression of phosphatidylinositol 3-kinase (PI3K) and phospho-Akt (p-Akt) in the DRG. Double immunofluorescence staining indicated that p-Akt was expressed in neurons in the DRG. Multiple injections of JTC-801 significantly inhibited the activation of Akt and decreased the expression of inflammatory cytokines. The data suggest that JTC-801 alleviates mechanical allodynia associated with paclitaxel-induced neuropathic pain via the PI3K/Akt pathway.

Therapeutic Efficacy Comparison of 5 Major EGFR-TKIs in Advanced EGFR-positive Non-Small-cell Lung Cancer: A Network Meta-analysis Based on Head-to-Head Trials.

BACKGROUND: Five major first- and second-generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), including erlotinib, gefitinib, icotinib, afatinib, and dacomitinib, are currently optional for patients with advanced non-small-cell lung cancer (NSCLC) who harbor EGFR mutations. However, there was no head-to-head-based network meta-analysis among all the TKIs in EGFR-mutated populations. METHODS: Eligible literature was searched from an electronic database. Data of objective response rate, disease control rate, progression-free survival, and overall survival were extracted from enrolled studies. Multiple treatment comparisons based on Bayesian network integrated the efficacy of all included treatments. RESULTS: Six phase III randomized trials involving 1055 EGFR-mutated patients with advanced NSCLC were enrolled. Multiple treatment comparisons showed that 5 different EGFR-TKIs shared equivalent therapeutic efficacy in terms of all outcome measures. Rank probabilities indicated that dacomitinib and afatinib had potentially better efficacy compared with erlotinib, gefitinib, and icotinib in the EGFR-mutated patients. When compared with other agents, potential survival benefits (progression-free and overall survival) were observed in dacomitinib, whereas afatinib showed a better rank probability in overall response rate and disease control rate. CONCLUSION: Our study indicated a preferable therapeutic efficacy in the second-generation TKIs (dacomitinib and afatinib) when compared with the first-generation TKIs (erlotinib, gefitinib, and icotinib).

Neurokinin-1 Receptor Antagonist-Based Triple Regimens in Preventing Chemotherapy-Induced Nausea and Vomiting: A Network Meta-Analysis.

Background: Neurokinin-1 receptor antagonists (NK-1RAs) are widely used for chemotherapy-induced nausea and vomiting (CINV) control in patients with highly emetogenic chemotherapy (HEC) and/or moderately emetogenic chemotherapy (MEC). Whether the efficacy and toxicity of antiemesis are different among various NK-1RA-based triple regimens is unknown. Methods: Data of complete responses (CRs) in the acute, delayed, and overall phases and treatment-related adverse events (TRAEs) were extracted from electronic databases. Efficacy and toxicity were integrated by pairwise and network meta-analyses. Results: Thirty-six trials involving 18 889 patients using triple regimens (NK-1RA+serotonin receptor antagonists [5HT3RA] + dexamethasone) or duplex regimen (5HT3RA+dexamethasone) to control CINV were included in the analysis. Different NK-1RA-based triple regimens shared equivalent effect on CRs. In patients with HEC, almost all triple regimens showed statistically significantly higher CRs than duplex regimen (odds ratio [OR]duplex/triple = 0.47-0.66). However, in patients with MEC, only aprepitant-based triple regimen showed better effect than duplex regimen statistically significantly in CRs (ORduplex/triple = 0.52, 95% confidence interval [CI] = 0.34 to 0.68). No statistically significant difference of TRAEs was found among different triple regimens. Palonosetron-based triple regimens were equivalent to first-generation 5HT3RAs-based triple regimens for CRs. Moreover, different doses of dexamethasone plus NK-1RA and 5HT3RA showed no statistically significant difference in CRs. Conclusions: Different NK-1RAs-based triple regimens shared equivalent effect on CINV control. Various triple regimens had superior antiemetic effect than duplex regimen in patients with HEC. Only aprepitant-based triple regimen showed better CINV control compared with duplex regimen in patients receiving MEC. Palonosetron and first-generation 5HT3RAs might share equivalent CINV control in the combination of NK-1RAs and dexamethasone. Lower doses of dexamethasone might be applied when used with NK-1RAs and 5HT3RAs.

Upregulation of PD-L1 by EML4-ALK fusion protein mediates the immune escape in ALK positive NSCLC: Implication for optional anti-PD-1/PD-L1 immune therapy for ALK-TKIs sensitive and resistant NSCLC patients.

Driver mutations were reported to upregulate programmed death-ligand 1 (PD-L1) expression. However, how PD-L1 expression and immune function was affected by ALK-TKIs and anti-PD-1/PD-L1 treatment in ALK positive non-small-cell lung cancer (NSCLC) remains poorly understood. In the present study, western-blot, real-time PCR, flow cytometry and immunofluorescence were employed to explore how PD-L1 was regulated by ALK fusion protein. ALK-TKIs and relevant inhibitors were used to identify the downstream signaling pathways involved in PD-L1 regulation. Cell apoptosis, viability and Elisa test were used to study the immune suppression by ALK activation and immune reactivation by ALK-TKIs and/or PD-1 blocking in tumor cells and DC-CIK cells co-culture system. We found that PD-L1 expression was associated with EGFR mutations and ALK fusion genes in NSCLC cell lines. Over-expression of ALK fusion protein increased PD-L1 expression. PD-L1 mediated by ALK fusion protein increased the apoptosis of T cells in tumor cells and DC-CIK cells co-culture system. Inhibiting ALK by sensitive TKIs could enhance the production of IFNγ. Anti-PD-1 antibody was effective in both crizotinib sensitive and resistant NSCLC cells. Synergistic tumor killing effects were not observed with ALK-TKIs and anti-PD-1 antibody combination in co-culture system. ALK-TKIs not only directly inhibited tumor viability but also indirectly enhanced the antitumor immunity via the downregulation of PD-L1. Anti-PD-1/PD-L1 antibodies could be an optional therapy for crizotinib sensitive, especially crizotinib resistant NSCLC patients with ALK fusion gene. Combination of ALK-TKIs and anti-PD-1/PD-L1 antibodies treatment for ALK positive NSCLC warrants more data before moving into clinical practice.

Development and validation of a nomogram for predicting the survival of patients with non-metastatic nasopharyngeal carcinoma after curative treatment.

BACKGROUND: The TNM staging system is far from perfect in predicting the survival of individual cancer patients because only the gross anatomy is considered. The survival rates of the patients who have the same TNM stage disease vary across a wide spectrum. This study aimed to develop a nomogram that incorporates other clinicopathologic factors for predicting the overall survival (OS) of non-metastatic nasopharyngeal carcinoma (NPC) patients after curative treatments. METHODS: We retrospectively collected the clinical data of 1520 NPC patients who were diagnosed histologically between November 2000 and September 2003. The clinical data of a separate cohort of 464 patients who received intensity-modulated radiation therapy (IMRT) between 2001 and 2010 were also retrieved to examine the extensibility of the model. Cox regression analysis was used to identify the prognostic factors for building the nomogram. The predictive accuracy and discriminative ability were measured using the concordance index (c-index). RESULTS: We identified and incorporated 12 independent clinical factors into the nomogram. The calibration curves showed that the prediction of OS was in good agreement with the actual observation in the internal validation set and IMRT cohort. The c-index of the nomogram was statistically higher than that of the 7th edition TNM staging system for predicting the survival in both the primary cohort (0.69 vs. 0.62) and the IMRT cohort (0.67 vs. 0.63). CONCLUSION: We developed and validated a novel nomogram that outperformed the TNM staging system in predicting the OS of non-metastatic NPC patients who underwent curative therapy.

Optimized selection of three major EGFR-TKIs in advanced EGFR-positive non-small cell lung cancer: a network meta-analysis.

BACKGROUND: To answer which epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) is the best choice for advanced non-small cell lung cancer (NSCLC) EGFR mutants. RESULTS: 16 phase III randomized trials involving 2962 advanced NSCLC EGFR mutants were enrolled. Multiple treatment comparisons showed different EGFR-TKIs shared equivalent curative effect in terms of all outcome measures among the overall, chemo-naïve and previously treated patients. Rank probabilities showed that erlotinib and afatinib had potentially better efficacy compared with gefitinib in both of the overall and chemo-naïve patients. Potentially survival benefit of erlotinib was also observed in previously treated patients compared with gefitinib. Additionally, EGFR-TKI showed numerically greater survival benefit in 19 Del compared with chemotherapy, while it was opposite in 21 L858R. Furthermore, afatinib, erlotinib and gefitinib had high, moderate and low risk of rash & diarrhea, respectively, while the occurrence of elevated liver transaminase was more common in gefitinib. METHODS: Data of objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and adverse events were extracted from included studies. Efficacy and toxicity of all included treatments were integrated by network meta-analyses. CONCLUSION: Our study indicated a high efficacy-high toxicity pattern of afatinib, a high efficacy-moderate toxicity pattern of erlotinib and a medium efficacy-moderate toxicity pattern of gefitinib. Recommended EGFR-TKI should be suggested according to patients' tolerability and therapeutic efficacy in clinical practice. Moreover, the treatment for advanced EGFR-positive NSCLC might be different between 19 Del and 21 L858R.

Impact of smoking status on EGFR-TKI efficacy for advanced non-small-cell lung cancer in EGFR mutants: a meta-analysis.

BACKGROUND: The strong association between smoking history and the presence of epidermal growth factor receptor (EGFR) mutations has been proven in non-small-cell lung cancer (NSCLC), which explains the favorable response to EGFR-tyrosine kinase inhibitor (EGFR-TKI) therapy in nonsmoking NSCLC patients. However, few studies directly focus on the relationship between EGFR-TKI's efficacy and smoking history in NSCLC EGFR-mutant patients. METHODS: Electronic databases were searched for eligible literatures. Data on objective response rates, disease control rates, and progression-free survival (PFS) stratified by smoking status were extracted and synthesized on the basis of a random-effect model. Subgroup and sensitivity analyses were conducted. RESULTS: A total of 9 studies that involved a total of 1029 EGFR-mutant advanced NSCLC patients after EGFR-TKI treatment were included. In overall, nonsmoking was associated with significant prolonged PFS (HR, 0.73, 0.60 to 0.88; P = .001) compared to ever smokers. However, only marginal improvements without statistical significance in objective response rates (odds ratio, 1.11; 95% confidence interval, 0.85 to 1.46; P = .433) and disease control rate (odds ratio, 1.04; 95% confidence interval, 0.82 to 1.33; P = .740) were observed. Subgroup analyses showed that the benefits of PFS in nonsmokers were predominantly presented in pooled results of studies enrolling patients with active EGFR mutations, studies involving previously treated patients, and retrospective studies. Additionally, we failed to observe any significant benefit from nonsmokers in every subgroup for objective response rates and disease control rate. CONCLUSION: For advanced NSCLC patients with EGFR mutations, nonsmoking is associated with longer PFS than ever smoking after EGFR-TKIs treatment. Smoking history should be considered an essential factor in studies regarding EGFR-targeted agents toward EGFR-mutant patients.

The efficacy of combining antiangiogenic agents with chemotherapy for patients with advanced non-small cell lung cancer who failed first-line chemotherapy: a systematic review and meta-analysis.

BACKGROUND: The clinical outcomes of patients with NSCLC who progressed after first-line treatments remain poor. The purpose of this study was to assess the advantage of antiangiogenic therapy plus standard treatment versus standard treatment alone for this population of patients. METHODS: We conducted a rigorous search using electronic databases for eligible studies reporting antiangiogenic therapy combined with standard second-line chemotherapy versus standard second-line treatment for patient who progressed after front-line treatment. Pooled risk ratio and 95% confidence intervals were calculated using proper statistical method. Predefined subgroup analyses were conducted to identify the potential proper patients. RESULTS: Thirteen phase II/III RCTs which involved a total of 8358 participants were included. Overall, there was significant improvement in OS (HR 0.94, 95%CI: 0.89-0.99, p=0.03), PFS (HR 0.80, 95%CI: 0.76-0.84, p<0.00001), ORR (RR 1.75, 95%CI: 1.55-1.98, p<0.00001) and DCR (RR 1.23, 95%CI: 1.18-1.28, p<0.00001) in the group with antiangiogenic therapy plus standard treatment versus the group with standard treatment alone. Subgroup analysis showed that OS benefit was presented only in patients treated with docetaxel plus antiangiogenic agents (HR 0.92, 95%CI: 0.86-0.99, p=0.02) and patients with non-squamous NSCLC (HR for OS 0.92, 95%CI: 0.86-0.99, p=0.02). CONCLUSIONS: This study revealed that the addition of antiangiogenic agents to the standard treatments could provide clinical benefit to NSCLC patients who failed their first-line therapy. Furthermore, proper selection of the combined standard cytotoxic agent, as well as the patient population by tumor histology, is warranted for future studies and clinical application of antiangiogenic therapy.

Upregulation of PD-L1 by EGFR Activation Mediates the Immune Escape in EGFR-Driven NSCLC: Implication for Optional Immune Targeted Therapy for NSCLC Patients with EGFR Mutation.

INTRODUCTION: Epidermal growth factor receptor (EGFR) mutation status was reported to be associated with programmed death-ligand 1 (PD-L1) expression. However, the molecular mechanism of PD-L1 regulation by EGFR activation and the potential clinical significance of blocking PD-1/PD-L1 in EGFR-mutant non-small-cell lung cancer (NSCLC) treated with EGFR tyrosine kinase inhibitors (TKIs) were largely unknown. METHODS: Western blot, real-time polymerase chain reaction, immunofluorescence, and flow cytometry were employed to explore the association between PD-L1 and EGFR activation. Then, we used EGFR-TKIs and downstream pathways inhibitors to clarify the detailed signaling pathway involved in PD-L1 regulation. Cell apoptosis, viability, and enzyme-linked immunosorbent assay test were used to study the immune suppression by EGFR activation and immune reactivation by EGFR-TKIs and/or PD-1 blocking in tumor cells and human peripheral blood mononuclear cells coculture system. RESULTS: We found that EGFR activation by EGF stimulation, exon-19 deletions, and L858R mutation could induce PD-L1 expression. EGFR activation upregulated PD-L1 through p-ERK1/2/p-c-Jun but not through p-AKT/p-S6 pathway. PD-L1 mediated by EGFR activation could induce the apoptosis of T cells through PD-L1/PD-1 axis in tumor cells and peripheral blood mononuclear cells coculture system. Inhibiting EGFR by EGFR-TKIs could free the inhibition of T cells and enhance the production of interferon-γ. Synergistic tumor cell killing effects were not observed with EGFR-TKIs and anti-PD-1 antibody combination treatment in coculture system. CONCLUSIONS: Our results imply that EGFR-TKIs could not only directly inhibit tumor cell viability but also indirectly enhance antitumor immunity through the downregulation of PD-L1. Anti-PD-1/PD-L1 antibodies could be an optional therapy for EGFR-TKI sensitive patients, especially for EGFR-TKIs resistant NSCLC patients with EGFR mutation. Combination of EGFR-TKIs and anti-PD-1/PD-L1 antibodies treatment in NSCLC is not supported by the current study but warrant more studies to move into clinical practice.

Prognostic significance of programmed cell death 1 (PD-1) or PD-1 ligand 1 (PD-L1) Expression in epithelial-originated cancer: a meta-analysis.

The expression of programmed cell death 1 (PD-1) and its ligand (PD-L1) has been observed in various epithelial-originated malignancies. However, whether the expression of PD-L1 on tumor cells or the expression of PD-1 on tumor-infiltrating lymphocytes (TILs) is associated with patients' survival remains controversial.Electronic databases were searched for eligible literatures. Data of hazard ratio (HR) for overall survival (OS) with 95% confidence interval (CI) according to the expression status of PD-L1 or PD-1 evaluated by immunohistochemistry were extracted. The outcomes were synthesized based on random-effects model. Subgroup analyses were proposed.Twenty-nine studies covering 12 types of epithelial-originated malignancies involving 7319 patients (2030/3641 cases for PD-L1 positive/negative, 505/1143 cases for PD-1 positive/negative) with available data of the outcome stratified by PD-L1/PD-1 status were enrolled. Epithelial-originated cancer patients with positive expression of PD-L1 on tumor tissues were associated with significantly poorer OS when compared to those with negative expression of PD-L1 (HR 1.81, 95% CI 1.33-2.46, P < 0.001). Similarly, patients with PD-1 positive expression on TILs had significantly shorter OS than the PD-1 negative group (HR 2.53, 95% CI 1.22-5.21, P = 0.012). In analyses of PD-L1, all subgroups showed consistent trends toward unfavorable prognoses of patients with positive PD-L1 expression, regardless of antibodies and evaluation cutoffs. Subgroup analyses on PD-1 were not available due to limited data.PD-L1 or PD-1 expression status is a significant prognostic factor in epithelial-originated malignancies.

Evaluation of the efficacy and safety of anti-PD-1 and anti-PD-L1 antibody in the treatment of non-small cell lung cancer (NSCLC): a meta-analysis.

BACKGROUND: Currently, blockade of the programmed cell death 1 (PD-1)/PD-1 ligand 1 (PD-L1) signaling pathway has been proved one of the most promising immunotherapeutic strategies against cancer. Several antibodies have been developed to either block the PD-1 or its ligand PD-L1 are under development. So far, a series of phase I trials on PD-1/PD-L1 antibodies for non-small cell lung cancer (NSCLC) have been completed, without reports of results from phase II studies. Thus, we sought to perform a meta-analysis incorporating all available evidences to evaluate the efficacy and safety of PD-1 or PD-L1 inhibition therapy. METHODS: Electronic databases were searched for eligible literatures. Data of objective respond rate (ORR) and rate of adverse effects (AEs) with 95% confidence interval (CI) evaluated by immunohistochemistry (IHC) was extracted. The outcomes were synthesized based on random-effect model. Subgroup analyses were proposed. RESULTS: In overall, ORR in the whole population with PD-1 blockage treatment is 22.5% (95% CI: 17.6% to 28.2%). Additionally, the rate of Grade 3-4 AEs is 16.7% (95% CI: 6.5% to 36.8%) and drug-related death rate is 2.5% (95% CI: 1.3% to 4.6%). As for patients with PD-L1 inhibition therapy, an overall ORR is 19.5% (95% CI: 13.2% to 27.7%). A higher rate of Grade 3-4 AEs (31.7%, 95% CI: 14.2% to 56.5%) is observed with a lower drug-related death rate (1.8%, 95% CI: 0.4% to 8.3%). In exploratory analyses of anti-PD-1 agents, we observed that greater ORR was presented in the median-dose cohort (3 mg/kg) than that of both low-dose (1 mg/kg) and high-dose (10 mg/kg) cohort (low-dose vs. median-dose: OR =0.12, P=0.0002; median-dose vs. high-dose: OR =1.47, P=0.18). CONCLUSIONS: Anti-PD-1 and anti PD-L1 antibodies showed objective responses in approximately one fourth NSCLC patients with a tolerable adverse-effect profile. In addition, median-dose (3 mg/kg) might be a preferential dosage of anti-PD-1 agents.

The Difference of Clinical Characteristics Between Patients With Exon 19 Deletion and Those With L858R Mutation in Nonsmall Cell Lung Cancer.

Recent studies have demonstrated that exon 19 deletion (19 Del) and exon 21 L858R mutation (L858R) are 2 different types of sensitive epidermal growth factor receptor (EGFR) mutations in nonsmall cell lung cancer (NSCLC). However, whether there are some differences between those 2 groups in baseline clinical characteristics is still unclear.We enrolled consecutive 1271 NSCLC patients detected with either 19 Del or L858R and collected their baseline clinical characteristics including age, sex, comorbidity, smoking and drinking status, body mass index (BMI), TNM stage, histologic type, differentiation, tumor maximum diameter (TMD), and CEA level. χ test and multivariate logistic regression analysis were used to compare the difference.We found a higher percentage of 19 Del in younger patients group (< = 50 yr) than L858R (P < 0.001) through χ test. Besides, patients with 19 Del have higher risk of lymph node metastasis (P < 0.001). However, there were no significant differences in other items of clinical characteristics between 19 Del and L858R. Multivariate analysis showed similar significant results. Subgroup analysis in different age groups (10 yr as an interval) and N stages (stratified by N0, N1, N2, and N3) also indicated above-mentioned trends.NSCLC patients with 19 Del are more likely to be young and have lymphatic metastasis than those with L858R. Age and N stage might be considered in predicting EGFR mutation type in NSCLC.

The association between PD-L1 and EGFR status and the prognostic value of PD-L1 in advanced non-small cell lung cancer patients treated with EGFR-TKIs.

BACKGROUNDS: Recent clinical trials have shown that immune-checkpoint blockade yields remarkable response in a subset of non-small cell lung cancer (NSCLC) patients. However, few studies directly focus on the association between epidermal growth factor receptor (EGFR) mutational status and programmed cell death-ligand 1 (PD-L1) expression. We examined whether PD-L1 is related to clinicopathologic factors and prognosis in patients with advanced NSCLC treated with EGFR-tyrosine kinase inhibitors (EGFR-TKIs). METHODS: One-hundred and seventy patients with advanced NSCLC were explored. Paraffin-embedded tumour sections were stained with PD-L1 antibody. EGFR mutation was examined by fluorescent quantitative polymerase chain reaction (PCR). The correlations between PD-L1 expression and EGFR status and survival parameters were analyzed. RESULTS: The overall frequency of PD-L1 over-expression was 65.9% (112/170). In lung adenocarcinoma, PD-L1 tended to be associated with mutant EGFR (PD-L1 overexpression in mutant and wild-type EGFR, 64/89 (71.9%) vs. 32/56 (57.1%), respectively; p=0.067). Subgroup analyses showed that high PD-L1 expression was associated with significantly shorter overall survival (OS) in EGFR wild-type patients (p=0.029) but not in EGFR mutant patients (p=0.932) treated with EGFR-TKIs. Even more, for EGFR mutant patients, higher expression of PD-L1 might only signal better outcome with TKIs. CONCLUSIONS: High PD-L1 expression was likely to be associated with the presence of EGFR mutation in advanced lung adenocarcinoma. For EGFR wild-type patients, the PD-L1 over expression can be considered as a poor prognostic indicator of OS.