Vactosertib, TGF-ß receptor I inhibitor, augments the sensitization of the anti-cancer activity of gemcitabine in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) exhibits a pronounced extracellular matrix (ECM)-rich response, which is produced by an excessive amount of transforming growth factor ß (TGF-ß), resulting in tumor progression and metastasis. In addition, TGF-ß signaling contributes to rapidly acquired resistance and incomplete response to gemcitabine. Recently, selective inhibitors of the TGF-ß signaling pathway have shown promise in PDAC treatment, particularly as an option for augmenting responses to chemotherapy. Here, we investigated the synergistic anticancer effects of a small-molecule TGF-ß receptor I kinase inhibitor (vactosertib/EW-7197) in the presence of gemcitabine, and its mechanism of action in pancreatic cancer. Vactosertib sensitized pancreatic cancer cells to gemcitabine by synergistically inhibiting their viability. Importantly, the combination of vactosertib and gemcitabine significantly attenuated the expression of major ECM components, including collagens, fibronectin, and α-SMA, in pancreatic cancer compared with gemcitabine alone. This resulted in potent induction of mitochondrial-mediated apoptosis, gemcitabine-mediated cytotoxicity, and inhibition of tumor ECM by vactosertib. Additionally, the combination decreased metastasis through inhibition of migration and invasion, and exhibited synergistic anti-cancer activity by inhibiting the TGF-ß/Smad2 pathway in pancreatic cancer cells. Furthermore, co-treatment significantly suppressed tumor growth in orthotopic models. Therefore, our findings demonstrate that vactosertib synergistically increased the antitumor activity of gemcitabine via inhibition of ECM component production by inhibiting the TGF-ß/Smad2 signaling pathway. This suggests that the combination of vactosertib and gemcitabine may be a potential treatment option for patients with pancreatic cancer.

A novel DDR1 inhibitor enhances the anticancer activity of gemcitabine in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is an extracellular matrix (ECM)-rich carcinoma, which promotes chemoresistance by inhibiting drug diffusion into the tumor. Discoidin domain receptor 1 (DDR1) increases tumor progression and drug resistance by binding to collagen, a major component of tumor ECM. Therefore, DDR1 inhibition may be helpful in cancer therapeutics by increasing drug delivery efficiency and improving drug sensitivity. In this study, we developed a novel DDR1 inhibitor, KI-301690 and investigated whether it could improve the anticancer activity of gemcitabine, a cytotoxic agent widely used for the treatment of pancreatic cancer. KI-301690 synergized with gemcitabine to suppress the growth of pancreatic cancer cells. Importantly, its combination significantly attenuated the expression of major tumor ECM components including collagen, fibronectin, and vimentin compared to gemcitabine alone. Additionally, this combination effectively decreased mitochondrial membrane potential (MMP), thereby inducing apoptosis. Further, the combination synergistically inhibited cell migration and invasion. The enhanced anticancer efficacy of the co-treatment could be explained by the inhibition of DDR1/PYK2/FAK signaling, which significantly reduced tumor growth in a pancreatic xenograft model. Our results demonstrate that KI-301690 can inhibit aberrant ECM expression by DDR1/PYK2/FAK signaling pathway blockade and attenuation of ECM-induced chemoresistance observed in desmoplastic pancreatic tumors, resulting in enhanced antitumor effect through effective induction of gemcitabine apoptosis.

Lidocaine enhances the efficacy of palbociclib in triple-negative breast cancer.

The use of anesthetics in the surgical resection of tumors may influence the prognosis of cancer patients. Lidocaine, a local anesthetic, is known to act as a chemosensitizer and relieve pain in some cancers. In addition, palbociclib, a potent cyclin-dependent kinase (CDK) 4/6 inhibitor, has been approved for chemotherapy of advanced breast cancer. However, recent studies have revealed the acquired resistance of breast cancer cells to palbociclib. Therefore, the development of combination therapies that can extend the efficacy of palbociclib or delay resistance is crucial. This study investigated whether lidocaine would enhance the efficacy of palbociclib in breast cancer. Lidocaine synergistically suppressed the growth and proliferation of breast cancer cells by palbociclib. The combination treatment showed an increased cell cycle arrest in the G0/G1 phase by decreasing retinoblastoma protein (Rb) and E2F1 expression. In addition, it increased apoptosis by loss of mitochondrial membrane potential as observed by increases in cytochrome c release and inhibition of mitochondria-mediated protein expression. Additionally, it significantly reduced epithelial-mesenchymal transition and PI3K/AKT/GSK3ß signaling. In orthotopic breast cancer models, this combination treatment significantly inhibited tumor growth and increased tumor cell apoptosis compared to those treated with a single drug. Taken together, this study demonstrates that the combination of palbociclib and lidocaine has a synergistic anti-cancer effect on breast cancer cells by the inhibition of the PI3K/AKT/GSK3ß pathway, suggesting that this combination could potentially be an effective therapy for breast cancer.

Managing Side Effects of Cytotoxic Chemotherapy in Patients With High Grade Gliomas.

Cytotoxic chemotherapy has been a mainstay of cancer treatment since the 1940s. In the recent era of emergent targeted therapies and immunotherapies, many cytotoxic chemotherapy agents including temozolomide are still one of main weapons for the treatment of high grade gliomas. However, cytotoxic chemotherapy often causes side effects. Proper management of chemotherapy-induced toxicity can have a significant impact on a patient's quality of life and clinical outcomes. Many supportive care advances have transformed our ability to give full doses of chemotherapy, which is important for achieving their full efficacy. Prevention and treatment strategies have been developed for many chemotherapy-related toxicities. This review focused on managing gastrointestinal toxicity, chemotherapy-induced nausea and vomiting, and hematologic toxicities such as thrombocytopenia during cytotoxic chemotherapy treatment in high-grade brain tumors.

Treatment Pattern, Financial Burden, and Outcomes in Elderly Patients with Acute Myeloid Leukemia in Korea: A Nationwide Cohort Study.

Although approximately 50% of patients with acute myeloid leukemia (AML) are diagnosed over the age of 60 years, there is currently no established consensus on the treatment of elderly AML patients. Herein, we aimed to explore the incidence, medical expenditure, treatment, and outcomes of elderly AML patients in Korea by analyzing a nationwide cohort. We employed the Korean National Health Insurance Service-Senior cohort, which represents 10% of a random selection from a total of 5.5 million subjects aged 60 years or older. AML patients were identified according to the main diagnostic criteria of acute leukemia. Treatment for AML was divided into high- (high-dose cytarabine ± idarubicin) and low- (low-dose cytarabine or hypomethylating agents) intensity chemo-therapy and classified according to the chemotherapeutics protocol. We analyzed the survival outcomes and medical expenditures. Among 558,147 elderly patients, 471 were diagnosed with AML, and 195 (41.4%) were treated with chemotherapy. The median age was 65 years, and the median overall survival (OS) was 4.93 months (95% confidence interval, 4.47-5.43). Median OS was longer in patients undergoing chemotherapy than those in the best supportive care group (6.28 vs. 3.45 months, p < 0.001), and the difference was prominent in patients aged < 70 years. Twenty-eight (5.9%) patients received high-intensity chemotherapy, while 146 (31.0%) received low-intensity chemotherapy. The difference in median OS according to dose intensity was 4.6 months, which was longer in the high-intensity chemotherapy group (9.8 vs. 5.2 months in low-intensity group); however, the difference was not statistically significant. Patients who received high-intensity chemotherapy recorded longer hospital stays and incurred greater expenses on initial hospitalization. Elderly AML patients in Korea exhibited clinical benefits from chemotherapy. Although patients should be carefully selected for intensive treatment, chemotherapy, including low-intensity treatment, can be considered in elderly patients. Moreover, prospective studies on new agents or new treatment strategies are needed.

Association of Smoking Status with Efficacy of First-line Immune Checkpoint Inhibitors in Advanced Non-small Cell Lung Cancers: A Systematic Review and Meta-analysis.

Background: Although smoking status has potential as a biomarker for immune checkpoint blockade in advanced non-small cell lung cancer (NSCLC), its clinical significance remains obscure. This meta-analysis aims to assess the impact of the smoking status on the efficacy of first-line immunotherapy and to find better treatment in never-smoker and ever-smoker patients. Methods: We searched the MEDLINE, EMBASE, and Cochrane database for trials comparing immunotherapy with conventional chemotherapy as front-line treatment for advanced NSCLC. Random-effects models were used to pool estimates of hazard ratios (HRs) for overall survival with 95% confidence intervals (CIs). Predefined subgroup analysis was performed to investigate the difference in the efficacy between the single checkpoint blockade and checkpoint inhibitor plus chemotherapy combination in the never-smokers and current/former smokers. Results: Twelve trials involving 6,446 patients were included in the analysis. A statistically significant overall survival benefit over conventional chemotherapy was found for both checkpoint inhibitor monotherapy (HR, 0.71; 95% CI, 0.59-0.85) and checkpoint inhibitor plus chemotherapy (HR, 0.75; 95% CI, 0.63-0.90) in the current/former smoker group. There was no subgroup difference between monotherapy and combination treatment (p=0.67). However, there was an inconsistent survival outcome in the never-smoker group; checkpoint blockade monotherapy did not show significantly better efficacy than chemotherapy alone (HR, 1.05; 95% CI, 0.81-1.37), but combination treatment showed an overall survival benefit (HR, 0.64; 95% CI, 0.43-0.94). A significant subgroup difference existed between monotherapy and combination therapy (p=0.04). Similarly, there was a significant difference in efficacy of monotherapy between the current/former smoker and never-smoker group (p=0.01), but the efficacy of the combination treatment was comparable between the two groups (p=0.45). Conclusion: Smoking status, which is easily available information, could be used as a guide in clinical practice to choose better treatment in the front-line setting for advanced NSCLC patients.

A Serum Marker for Early Pancreatic Cancer With a Possible Link to Diabetes.

BACKGROUND: Pancreatic cancer (PC) has a grim prognosis, and an early diagnostic biomarker has been highly desired. The molecular link between diabetes and PC has not been well established. METHODS: Bioinformatics screening was performed for a serum PC marker. Experiments in cell lines (5 PC and 1 normal cell lines), mouse models, and human tissue staining (37 PC and 10 normal cases) were performed to test asprosin production from PC. Asprosin's diagnostic performance was tested with serums from multi-center cohorts (347 PC, 209 normal, and 55 additional diabetic patients) and evaluated according to PC status, stages, and diabetic status, which was compared with that of CA19-9. RESULTS: Asprosin, a diabetes-related hormone, was found from the bioinformatics screening, and its production from PC was confirmed. Serum asprosin levels from multi-center cohorts yielded an age-adjusted diagnostic area under the curve (AUC) of 0.987 (95% confidence interval [CI] = 0.961 to 0.997), superior to that of CA19-9 (AUC = 0.876, 95% CI = 0.847 to 0.905), and a cut-off of 7.18 ng/mL, at which the validation set exhibited a sensitivity of 0.957 and a specificity of 0.924. Importantly, the performance was maintained in early-stage and non-metastatic PC, consistent with the tissue staining. A slightly lower performance against additional diabetic patients (n = 55) was restored by combining asprosin and CA19-9 (AUC = 0.985, 95% CI = 0.975 to 0.995). CONCLUSIONS: Asprosin is presented as an early-stage PC serum marker that may provide clues for PC-induced diabetes. Larger prospective clinical studies are warranted to solidify its utility.

Intracellular KRAS-specific antibody enhances the anti-tumor efficacy of gemcitabine in pancreatic cancer by inducing endosomal escape.

KRAS mutation is associated with the progression and growth of pancreatic cancer and contributes to chemo-resistance, which poses a significant clinical challenge in pancreatic cancer. Here, we developed a RT22-ep59 antibody (Ab) that directly targets the intracellularly activated GTP-bound form of oncogenic KRAS mutants after it is internalized into cytosol by endocytosis through tumor-associated receptor of extracellular epithelial cell adhesion molecule (EpCAM) and investigated its synergistic anticancer effects in the presence of gemcitabine in pancreatic cancer. We first observed that RT22-ep59 specifically recognized tumor-associated EpCAM and reached the cytosol by endosomal escape. In addition, the anticancer effect of RT22-ep59 was observed in the high-EpCAM-expressing pancreatic cancer cells and gemcitabine-resistant pancreatic cancer cells, but it had little effect on the low-EpCAM-expressing pancreatic cancer cells. Additionally, co-treatment with RT22-ep59 and gemcitabine synergistically inhibited cell viability, migration, and invasion in 3D-cultures and exhibited synergistic anticancer activity by inhibiting the RAF/ERK or PI3K/AKT pathways in cells with high-EpCAM expression. In an orthotopic mouse model, combined administration of RT22-ep59 and gemcitabine significantly inhibited tumor growth. Furthermore, the co-treatment suppressed cancer metastasis by blocking EMT signaling in vitro and in vivo. Our results demonstrated that RT22-ep59 synergistically increased the antitumor activity of gemcitabine by inhibiting RAS signaling by specifically targeting KRAS. This indicates that co-treatment with RT22-ep59 and gemcitabine might be considered a potential therapeutic strategy for pancreatic cancer patients harboring KRAS mutation.

2020 Korean guidelines for the management of metastatic prostate cancer.

In 2017, Korean Society of Medical Oncology (KSMO) published the Korean management guideline of metastatic prostate cancer. This paper is the 2nd edition of the Korean management guideline of metastatic prostate cancer. We updated recent many changes of management in metastatic prostate cancer in this 2nd edition guideline. The present guideline consists of the three categories: management of metastatic hormone sensitive prostate cancer; management of metastatic castration resistant prostate cancer; and clinical consideration for treating patients with metastatic prostate cancer. In category 1 and 2, levels of evidence (LEs) have been mentioned according to the general principles of evidence-based medicine. And grades of recommendation (GR) was taken into account the quality of evidence, the balance between desirable and undesirable effects, the values and preferences, and the use of resources and GR were divided into strong recommendations (SR) and weak recommendations (WR). A total of 16 key questions are selected. And we proposed recommendations and described key evidence for each recommendation. The treatment landscape of metastatic prostate cancer is changing very rapid and many trials are ongoing. To verify the results of the future trials is necessary and should be applied to the treatment for metastatic prostate cancer patients in the clinical practice. Especially, many prostate cancer patients are old age, have multiple underlying medical comorbidities, clinicians should be aware of the significance of medical management as well as clinical efficacy of systemic treatment.

ANGPTL4 exacerbates pancreatitis by augmenting acinar cell injury through upregulation of C5a.

Pancreatitis is the inflammation of the pancreas. However, little is known about the genes associated with pancreatitis severity. Our microarray analysis of pancreatic tissues from mild and severe acute pancreatitis mice models identified angiopoietin-like 4 (ANGPTL4) as one of the most significantly upregulated genes. Clinically, ANGPTL4 expression was also increased in the serum and pancreatic tissues of pancreatitis patients. The deficiency in ANGPTL4 in mice, either by gene deletion or neutralizing antibody, mitigated pancreatitis-associated pathological outcomes. Conversely, exogenous ANGPTL4 exacerbated pancreatic injury with elevated cytokine levels and apoptotic cell death. High ANGPTL4 enhanced macrophage activation and infiltration into the pancreas, which increased complement component 5a (C5a) level through PI3K/AKT signaling. The activation of the C5a receptor led to hypercytokinemia that accelerated acinar cell damage and furthered pancreatitis. Indeed, C5a neutralizing antibody decreased inflammatory response in LPS-activated macrophages and alleviated pancreatitis severity. In agreement, there was a significant positive correlation between C5a and ANGPTL4 levels in pancreatitis patients. Taken together, our study suggests that targeting ANGPTL4 is a potential strategy for the treatment of pancreatitis.

MEK blockade overcomes the limited activity of palbociclib in head and neck cancer.

Head and neck cancer (HNC) is characterized with multiple aberrations in cell cycle pathways, including amplification of cyclin D1. Palbociclib (PAL), a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor, has been reported to regulate cell cycle progression in HNC. However, recent studies have revealed the acquired resistance of certain cells to PAL through activation of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway. Therefore, we investigated whether the inhibition of MEK/ERK pathway by trametinib (TRA) may overcome the limited efficacy of PAL in HNC. We evaluated the effect of PAL alone and in combination with TRA on the viability of HNC cells, and found that the combination treatment synergistically inhibited the proliferation of HNC cells. The combination treatment induced G0/G1 cell cycle arrest and apoptotic cell death. In particular, apoptosis mediated by the combination treatment was accompanied with an increase in caspase-3 activity and the number of TUNEL-positive apoptotic cells. These results were consistent with the decrease in cell cycle progression and mitogen-activated protein kinase (MAPK) pathway activation. In a xenograft mouse model of HNC, PAL and TRA synergistically inhibited tumor growth and enhanced tumor cell apoptosis, consistent with the increase in the number of TUNEL-positive cells. The anti-proliferative effects were evident in tumor tissues subjected to the combination treatment as compared with those treated with single drug. Taken together, our study demonstrates that the combination of PAL and TRA exerts synergistic anticancer effects and inhibits cell cycle check points and MEK/ERK pathway in HNC, suggestive of their potential application for HNC treatment.

SB365 induces apoptosis and suppresses proliferation of glioblastoma cells.

CONTEXT: Glioblastoma is a malignant brain tumor with limited treatment modalities due to its nature. SB365, Pulsatilla saponin D, is known to induce apoptosis and inhibit the growth of many cancer cells. AIM: We elucidated the anticancer effects of SB365 in glioblastoma cells. METHODS: We examined the antiproliferative activity of SB365 in human glioblastoma cell lines. Apoptosis was evaluated using the Hoechst assay, TUNEL assay, DAPI nuclear staining, and Western blotting analysis. To test the antimetastatic capacity of SB365, cell migration assay was conducted, and hypoxia-inducible factor-1 alpha (HIF-1α) expression and vascular endothelial growth factor (VEGF) level were determined under hypoxic conditions. STATICAL ANALYSIS: Significance of the results was confirmed by a one-way analysis of variance analysis. RESULTS: SB365 treatment suppressed the growth of glioblastoma cells and resulted in apoptotic morphological features such as nuclear condensation and fragmentation, enhancing the expression of cleaved poly (ADP-ribose) polymerase and caspase-3. It also significantly delayed cell migration and decreased the HIF-1α expression and VEGF secretion. CONCLUSION: Our findings thus demonstrate that SB365 induced apoptosis and delayed the growth and migration of human glioblastoma cells. It is considered that SB365 would be a promising therapeutic option for glioblastoma.

PBT-6, a Novel PI3KC2γ Inhibitor in Rheumatoid Arthritis.

Phosphoinositide 3-kinase (PI3K) is considered as a promising therapeutic target for rheumatoid arthritis (RA) because of its involvement in inflammatory processes. However, limited studies have reported the involvement of PI3KC2γ in RA, and the underlying mechanism remains largely unknown. Therefore, we investigated the role of PI3KC2γ as a novel therapeutic target for RA and the effect of its selective inhibitor, PBT-6. In this study, we observed that PI3KC2γ was markedly increased in the synovial fluid and tissue as well as the PBMCs of patients with RA. PBT-6, a novel PI3KC2γ inhibitor, decreased the cell growth of TNF-mediated synovial fibroblasts and LPS-mediated macrophages. Furthermore, PBT-6 inhibited the PI3KC2γ expression and PI3K/ AKT signaling pathway in both synovial fibroblasts and macrophages. In addition, PBT-6 suppressed macrophage migration via CCL2 and osteoclastogenesis. In CIA mice, it significantly inhibited the progression and development of RA by decreasing arthritis scores and paw swelling. Three-dimensional micro-computed tomography confirmed that PBT-6 enhanced the joint structures in CIA mice. Taken together, our findings suggest that PI3KC2γ is a therapeutic target for RA, and PBT-6 could be developed as a novel PI3KC2γ inhibitor to target inflammatory diseases including RA.

Effect of study-level factors on treatment-free remission rate in patients with chronic myeloid leukemia: a systematic review and meta-analysis.

As it is recommended that most assessments for treatment-free remission (TFR) in patients with chronic myeloid leukemia be conducted as prospective trials, we conducted a systematic review and meta-analysis to investigate which study-level factors affected the TFR rate. The MEDLINE, Embase, and Cochrane databases were systematically searched from inception to July 2018. A random effect model was used to estimate the overall mean TFR rate, subgroup differences, and regression coefficients with continuous variables. Overall, 12 tyrosine kinase inhibitor (TKI) stopping studies comprising 1699 chronic myeloid leukemia patients were included in this analysis. The overall mean TFR rate at 24 months after entering TFR phase was 55% [95% confidence interval (CI) 0.51-0.58]. Trials with molecular criteria of MR4.5 or better for stopping TKI reported higher TFR rates than those of MR4.0 (57.2% vs. 50.5%). Trials with eligible criteria for at least 24 months of deep molecular response (DMR) duration demonstrated higher TFR rates than those for 18 or 12 months (60.2% vs. 49.9%). Our results suggest that TKI stopping trials with sufficient duration of DMR and molecular criteria of MR4.5 or better may account for approximately 60% of the TFR rate at 24 months after stopping TKI.

Relative Efficacy of Systemic Treatments for Patients with Advanced Hepatocellular Carcinoma According to Viral Status: A Systematic Review and Network Meta-Analysis.

BACKGROUND: Several clinical trials that tested the efficacy of systemic treatments for advanced hepatocellular carcinoma (HCC) showed a tendency that patients with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection had different survival benefits from targeted agents. OBJECTIVE: The objective of this study was to assess the comparative efficacy of systemic targeted therapies according to HBV and HCV status in first-line and second- or later-line treatments for advanced HCC. METHODS: PubMed, EMBASE, Cochrane database, and meeting abstracts were searched through to January 2019. A Bayesian network meta-analysis was performed to estimate hazard ratios (HRs) for overall survival with 95% credible intervals (CrIs) and determine the ranking of the included regimens. RESULTS: Sixteen trials involving 6410 patients were included in the meta-analysis. In the first-line treatment setting, lenvatinib was the best agent for both HBV and HCV subgroups, presenting the most favorable HR versus sorafenib (HR 0.83, 95% CrI 0.68-1.01 and HR 0.91, 95% CrI 0.66-1.25, respectively), and was ranked as the best agent [surface under the cumulative ranking curve (SUCRA) value of 87% and 85%, respectively] among the included drugs. In second-line therapy, regorafenib showed the lowest HR versus placebo (HR 0.58, 95% CrI 0.41-0.82) in the HBV subgroup, whereas no agent was significantly more effective than placebo in the HCV subgroup. CONCLUSIONS: Compared with sorafenib, lenvatinib was more efficacious in the HBV subgroup than in the HCV subgroup, and the relative ranking of sorafenib in the HBV subgroup was lower than in the HCV subgroup. Each targeted agent reported to be the best by viral etiology and line of treatment could be carefully recommended in each subgroup.

An Integrative Data Mining and Omics-Based Translational Model for the Identification and Validation of Oncogenic Biomarkers of Pancreatic Cancer.

Substantial alterations at the multi-omics level of pancreatic cancer (PC) impede the possibility to diagnose and treat patients in early stages. Herein, we conducted an integrative omics-based translational analysis, utilizing next-generation sequencing, transcriptome meta-analysis, and immunohistochemistry, combined with statistical learning, to validate multiplex biomarker candidates for the diagnosis, prognosis, and management of PC. Experiment-based validation was conducted and supportive evidence for the essentiality of the candidates in PC were found at gene expression or protein level by practical biochemical methods. Remarkably, the random forests (RF) model exhibited an excellent diagnostic performance and LAMC2, ANXA2, ADAM9, and APLP2 greatly influenced its decisions. An explanation approach for the RF model was successfully constructed. Moreover, protein expression of LAMC2, ANXA2, ADAM9, and APLP2 was found correlated and significantly higher in PC patients in independent cohorts. Survival analysis revealed that patients with high expression of ADAM9 (Hazard ratio (HR)OS = 2.2, p-value < 0.001), ANXA2 (HROS = 2.1, p-value < 0.001), and LAMC2 (HRDFS = 1.8, p-value = 0.012) exhibited poorer survival rates. In conclusion, we successfully explore hidden biological insights from large-scale omics data and suggest that LAMC2, ANXA2, ADAM9, and APLP2 are robust biomarkers for early diagnosis, prognosis, and management for PC.

Surrogate decision making of chemotherapy consent: do we really provide informed consent of chemotherapy for patients?

BACKGROUND/AIMS: Despite increased demand for cancer patient's to make their own decisions based on an adequate understanding of what is involved in chemotherapy, the primary signing agent and the reasons for surrogate signing have not been appropriately evaluated. METHODS: The ethics committee of the palliative medicine subgroup of the Korean Cancer Study Group designed this study and solid cancer patients to whom chemotherapy was offered, from seven institutions, were evaluated. The details relating to surrogate's signing of chemotherapy consent were evaluated. Then, we analyzed the factors associated with surrogate's signing according to patient's demographics and characteristics related to chemotherapy consent. RESULTS: Surrogate's signing was noted for 20.7% (84/405) of patient and over half of surrogate signings were performed by the patients' son or daughter (60.7%). Two main reasons for surrogate signing were patient's incapacity (34.5%) and taking over authorization from patients (33.3%). The factors associated with more frequent surrogate's signing were absence of spouse, lower education level, outpatient, and when residents played a role as a principle provider of chemotherapy consent. CONCLUSION: This study suggests the lack of patients' own decision making for chemotherapy in some situations. This ethical dilemma must be considered for adequately informed decision making for chemotherapy while ensuring the patients' autonomy is maintained.

HS-173 as a novel inducer of RIP3-dependent necroptosis in lung cancer.

Necroptosis is a form of regulated necrotic cell death mediated by receptor-interacting kinase 3 (RIP3). Recently, necroptosis has gained attention as a novel alternative therapy to target cancer cells. In this study, we screened several chemotherapeutics used in preclinical and clinical studies, and identified a drug HS-173 that induces RIP3-mediated necroptosis. HS-173 decreased the cell survival in a dose-dependent manner in RIP3-expressing lung cancer cells, compared to the cells lacking RIP3. Also, the cell death induced by HS-173 was rescued by specific necroptosis inhibitors such as necrostatin-1 and dabrafenib. Additionally, HS-173 increased the phosphorylation of RIP3 and MLKL, which was decreased by necroptosis inhibitors, indicating that HS-173 activates RIP3/MLKL signaling in lung cancer cells. HS-173 increased the necroptotic events, as observed by the increased levels of HMGB1 and necroptotic morphological features. Furthermore, HS-173 inhibited the tumor growth by stimulation of necroptosis in mouse xenograft models. Our findings offer new insights into the role of HS-173 in inducing necroptosis by enhancing RIP3 expression and activating the RIP3/MLKL signaling pathway in lung cancer cells.

KRAS targeting antibody synergizes anti-cancer activity of gemcitabine against pancreatic cancer.

Pancreatic cancer exhibits an oncogenic KRAS mutation rate of ∼90%. Despite research and drug development efforts focused on KRAS, no targeted therapy has been clinically approved for the treatment of pancreatic cancer with KRAS mutation. Also, the efficacy of gemcitabine is poor due to rapidly acquired resistance. We developed RT11-i antibody, which directly targets the intracellularly activated GTP-bound form of oncogenic RAS mutants. Here, we investigated the combined effects of RT11-i and gemcitabine in vitro and in vivo, and the mechanism involved. RT11-i significantly sensitized pancreatic cancer cells to gemcitabine. Also, the co-treatment synergistically inhibited angiogenesis, migration, and invasion, and showed synergistic anticancer activity by inhibiting the RAF/MEK/ERK or PI3K/AKT pathways. Furthermore, co-treatment inhibited endothelial barrier disruption in tumor vessels, which is a critical step in vascular leakiness of metastasis, and improved vessel structural stability. Importantly, co-treatment significantly suppressed tumor growth in an orthotopic tumor model. Taken together, our findings show that RT11-i synergistically increased the antitumor activity of gemcitabine by inhibiting RAS downstream signaling, which suggests RT11-i and gemcitabine be viewed a potential combination treatment option for pancreatic cancer patients with KRAS mutation.

Relative Efficacy of Checkpoint Inhibitors for Advanced NSCLC According to Programmed Death-Ligand-1 Expression: A Systematic Review and Network Meta-Analysis.

Although currently available immune checkpoint inhibitors with similar but slightly different indications are recommended for patients with advanced non-small cell lung cancer (NSCLC), their effects by programmed death-ligand-1 (PD-L1) expression level are not yet known. This meta-analysis aims to assess the survival benefit and comparative efficacy of checkpoint inhibitors according to PD-L1 expression level: <1%, 1-49%, and ≥50%. We searched the MEDLINE, EMBASE, and Cochrane database through December 2017. A fixed-effect Bayesian network meta-analysis (NMA) was performed to estimate hazard ratios (HRs) for overall survival (OS) with 95% credible intervals (CrIs). Seven trials including 3688 patients were selected from among the 673 screened studies. Checkpoint inhibitor remarkably improved OS over chemotherapy in the PD-L1 ≥ 50% subgroup compared with the PD-L1 < 1% and PD-L1 1-49% subgroups. Atezolizumab, nivolumab, and nivolumab were the most effective agents for second- or later-line settings in the PD-L1 < 1%, PD-L1 1-49%, and PD-L1 ≥ 50% subgroups, respectively. PD-L1 expression ≥50% on tumor cells could be a reliable indicator that helps patient selection in view of cost-efficiency, and each checkpoint inhibitor reported to be the best agent by PD-L1 expression level could be carefully recommended in each PD-L1 expression subgroup.