Accumulating evidence indicates that a small population of cancer stem cells (CSCs) is involved in intrinsic resistance to cancer treatment. The hypoxic microenvironment is an important stem cell ...niche that promotes the persistence of CSCs in tumors. Our aim here was to elucidate the role of hypoxia and CSCs in the resistance to gefitinib in non-small cell lung cancer (NSCLC) with activating epidermal growth factor receptor (EGFR) mutation. NSCLC cell lines, PC9 and HCC827, which express the EGFR exon 19 deletion mutations, were exposed to high concentration of gefitinib under normoxic or hypoxic conditions. Seven days after gefitinib exposure, a small fraction of viable cells were detected, and these were referred to as "gefitinib-resistant persisters" (GRPs). CD133, Oct4, Sox2, Nanog, CXCR4, and ALDH1A1-all genes involved in stemness-were highly expressed in GRPs in PC9 and HCC827 cells, and PC9 GRPs exhibited a high potential for tumorigenicity in vivo. The expression of insulin-like growth factor 1 (IGF1) was also upregulated and IGF1 receptor (IGF1R) was activated on GRPs. Importantly, hypoxic exposure significantly increased sphere formation, reflecting the self-renewal capability, and the population of CD133- and Oct4-positive GRPs. Additionally, hypoxia upregulated IGF1 expression through hypoxia-inducible factor 1α (HIF1α), and markedly promoted the activation of IGF1R on GRPs. Knockdown of IGF1 expression significantly reduced phosphorylated IGF1R-expressing GRPs under hypoxic conditions. Finally, inhibition of HIF1α or IGF1R by specific inhibitors significantly decreased the population of CD133- and Oct4-positive GRPs, which were increased by hypoxia in PC9 and HCC827 cells. Collectively, these findings suggest that hypoxia increased the population of lung CSCs resistant to gefitinib in EGFR mutation-positive NSCLC by activating IGF1R. Targeting the IGF1R pathway may be a promising strategy for overcoming gefitinib resistance in EGFR mutation-positive NSCLC induced by lung CSCs and microenvironment factors such as tumor hypoxia.
Cerebral ischemia causes delayed neuronal cell death in the hippocampus resulting in sequential cognitive impairments. Hyper-activated inflammation following ischemia is one of the etiologies for ...delayed neuronal cell death. In the present study, using a transient global ischemia mouse model, we showed that auraptene (AUR), a citrus coumarin, effectively inhibited microglia activation, cyclooxygenase-2 expression by astrocytes, and neuronal cell death in the hippocampus following ischemic insults. These results suggest that AUR acts as a neuroprotective agent in the ischemic brain, which may be mediated by suppression of the inflammatory response.
The prognosis of patients with NSCLC harboring oncogenic driver gene alterations, such as EGFR gene mutations or ALK fusion, has improved dramatically with the advent of corresponding molecularly ...targeted drugs. As patients were followed up for about five years in most clinical trials, the long-term outcomes beyond 5 years are unclear. The objectives of this study are to explore the clinical course beyond five years of chemotherapy initiation and to investigate factors that lead to long-term survival.
One hundred and seventy-seven patients with advanced, EGFR-mutated or ALK-rearranged NSCLC who received their first chemotherapy between December 2008 and September 2015 were included. Kaplan Meier curves were drawn for the total cohort and according to subgroups of patients' characteristics.
Median OS in the total cohort was 40.6 months, the one-year survival rate was 89%, the three-year survival rate was 54%, and the five-year survival rate was 28%. Median OS was 36.9 months in EGFR-mutated patients and 55.4 months in ALK-rearranged patients. The OS curve seemed to plateau after 72 months, and most of the patients who were still alive after more than five years are on treatment. Female sex, age under 75 years, an ECOG PS of 0 to 1, ALK rearrangement, postoperative recurrence, and presence of brain metastasis were significantly associated with longer OS.
A tail plateau was found in the survival curves of patients with advanced, EGFR-mutated and ALK-rearranged NSCLC, but most were on treatment, especially with EGFR-mutated NSCLC.
Several recent studies have suggested that cancer stem cells (CSCs) are involved in resistance to gefitinib in non-small cell lung cancer (NSCLC). Oct4, a member of the POU-domain transcription ...factor family, has been shown to be involved in CSC properties of various cancers. We previously reported that Oct4 and the putative lung CSC marker CD133 were highly expressed in gefitinib-resistant persisters (GRPs) in NSCLC cells, and GRPs exhibited characteristic features of the CSCs phenotype. The aim of this study was to elucidate the role of Oct4 in the resistance to gefitinib in NSCLC cells with an activating epidermal growth factor receptor (EGFR) mutation. NSCLC cell lines, PC9, which express the EGFR exon 19 deletion mutation, were transplanted into NOG mice, and were treated with gefitinib in vivo. After 14–17 days of gefitinib treatment, the tumors still remained; these tumors were referred to as gefitinib-resistant tumors (GRTs). PC9-GRTs showed higher expression of Oct4 and CD133. To investigate the role of Oct4 in the maintenance of gefitinib-resistant lung CSCs, we introduced the Oct4 gene into PC9 and HCC827 cells carrying an activating EGFR mutation by lentiviral infection. Transfection of Oct4 significantly increased CD133-positive GRPs and the number of sphere formation, reflecting the self-renewal activity, of PC9 and HCC827 cells under the high concentration of gefitinib in vitro. Furthermore, Oct4-overexpressing PC9 cells (PC9-Oct4) significantly formed tumors at 1 × 10 cells/injection in NOG mice as compared to control cells. In addition, PC9-Oct4 tumors were more resistant to gefitinib treatment as compared to control cells in vivo. Finally, immunohistochemical analysis revealed that Oct4 was highly expressed in tumor specimens of EGFR-mutant NSCLC patients with acquired resistance to gefitinib. Collectively, these findings suggest that Oct4 plays a pivotal role in the maintenance of lung CSCs resistant to gefitinib in EGFR mutation-positive NSCLC.
•Oct4 is highly expressed in gefitinib-resistant tumors of EGFR-mutant NSCLC in vivo.•Oct4 induces gefitinib resistance in vitro and in vivo.•Oct4 increases CD133-positive gefitinib-resistant persisters.•Oct4 promotes properties of cancer stem cells under the gefitinib treatment.•Oct4 is highly expressed in tumors of patients with acquired resistance to gefitinib.
Background The combination of immune-checkpoint inhibitors with chemotherapy has become the standard of treatment for non-small cell lung cancer (NSCLC) patients. However, the association between ...therapeutic efficacy and the development of immune-related adverse events (irAEs) remains unclear in patients treated with combination therapy. We aimed to investigate the frequency of irAEs, and the association between therapeutic efficacy and the development of irAEs in patients with NSCLC. Materials and methods We retrospectively surveyed patients with chemo-naïve advanced NSCLC who received pembrolizumab plus platinum-based chemotherapy or pembrolizumab monotherapy at Juntendo University Hospital, Japan, between February 2017 and May 2021. Results Among 148 patients (median range age, 68 (33-85) years; 107 men 72.3% and 41 women 27.7%), 74 each received pembrolizumab plus chemotherapy and pembrolizumab monotherapy. IrAEs were observed in 46 (62.2%) and 41 patients (55.4%) in the combination therapy and monotherapy group, respectively. Patients with irAEs showed significantly longer progression-free survival (PFS) than those without irAEs in the combination therapy group (8.9 vs. 5.7 months; Hazard Ratio HR, 0.53; 95% CI, 0.29-0.98; P = 0.041) and monotherapy group (11.7 vs. 5.0 months; HR, 0.40; 95% CI, 0.22-0.70; P = 0.001). In the multivariable analysis, development of irAEs was positively associated with PFS in both the groups (HR, 0.48; 95% CI, 0.26-0.89; P = 0.019 and HR, 0.38; 95% CI, 0.21-0.68; P < 0.01). In the inverse probability of treatment weighting adjusted analysis, development of irAEs was significantly associated with combination therapy (OR, 0.56; 95% CI, 0.34-0.91; P = 0.019). Conclusion Our study demonstrated that the incidence of irAEs was associated with favorable efficacy in patients treated with pembrolizumab plus chemotherapy, as well as pembrolizumab monotherapy. Also, the addition of chemotherapy to pembrolizumab significantly increased the incidence of irAEs. Keywords: Non-small cell lung cancer, Immune-checkpoint inhibitors, Combination therapy, Immune-related adverse events
Malignant pleural mesothelioma (MPM) is a highly aggressive tumor that has a low overall survival; however, no significant treatment advances have been made in the past 15 years. Large-scale ...molecular studies have identified a poor prognostic subset of MPM linked to the epithelial-mesenchymal transition (EMT) that may contribute toward resistance to chemotherapy, suggesting that EMT could be targeted to treat patients with MPM. Previously, we reported that histone modifiers regulating EMT could be therapeutic targets; therefore, in this study, we investigated whether targeting lysine-specific demethylase 1 (LSD1/KDM1), a histone-modifying enzyme responsible for demethylating histone H3 lysine 4 and lysine 9, could represent a novel therapeutic strategy for MPM. We suppressed LSD1 and investigated the EMT phenotype using EMT marker expression and wound-healing assay; and chemosensitivity using apoptosis assay. We found that suppressing LSD1 induces an epithelial phenotype in sarcomatoid MPM cells, while attenuating the mesenchymal phenotype sensitized MPM cells to cisplatin-induced apoptosis. Subsequent genome-wide identification, comprehensive microarray analysis, and Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) to assess genome-wide changes in chromatin accessibility suggested that LSD1 directly regulates milk fat globulin protein E8 (MFGE8), an integrin ligand that is involved in the FAK pathway. Furthermore, we found that LSD1 regulates the mesenchymal phenotype and apoptosis by activating the FAK-AKT-GSK3β pathway via a positive feedback loop involving MFGE8 and Snail expression, thereby leading to cisplatin resistance. IMPLICATIONS: This study suggests that LSD1 regulates the mesenchymal phenotype and apoptosis, and that LSD1 inhibitors could be combined with the cisplatin as a novel therapy for patients with MPM.
Home-school partnership is key to students' success at schools. Japanese schools have attempted to invite families to participate in school educational activities. However, these efforts are embedded ...into Japanese school cultures and were not studied empirically. This study aimed to explore teachers' attitudes and actions toward home-school partnership and examine their effects on teachers' burnout. Based on a preliminary study, we developed a questionnaire with 30 items for the partnership attitude (PAT) scale, 37 items for the partnership actions (PAC) scale and three other scales. We examined the concurrent validity of the scales with a sample of 254 teachers. Exploratory factor analysis yielded four subscales for the PAT (Appreciation, Positive Attitude, Traditional Attitude, Difficulty) and five subscales for the PAC (Respect Parents, Individual Contact, Classroom Information Sharing, Being Proactive, Facilitating Conversation). Reliability was moderately supported, while the criterion validity coefficients were moderately supported using correlation analysis. The results of the multiple regressions show that some PAT factors had negative effects, while some PAC factors had positive effects on teachers' burnout. Thus, while it is important for teachers to build a good home-school partnership through partnership actions, a systematic support system is necessary for teachers experiencing difficulties in collaborating with parents.
A 64-year-old man with the bone marrow metastasis due to malignant pleural mesothelioma (MPM) was diagnosed with anemia, leukoerythroblastosis, thrombocytopenia, and lower back pain. A bone marrow ...biopsy demonstrated infiltrative malignant mesothelioma lesions in the bone marrow. The patient died within 15 days of the detection of the bone marrow involvement. Physicians should consider performing a bone marrow biopsy to diagnose bone marrow metastasis and treat patients with palliative chemotherapy at an earlier phase of the disease. To our knowledge, this is the first report of an MPM patient having bone marrow metastasis with anemia, leukoerythroblastosis, and thrombocytopenia.
In a 7-year (2002–2008) retrospective study of a large IVF program based on minimal ovarian stimulation and single ET (47,841 single ETs), monozygotic twinning occurred in 1.01% of 14,956 clinical ...pregnancies. Blastocyst culture was associated with a significantly increased monozygotic twinning risk (adjusted odds ratio, 2.04; 95% confidence interval, 1.29–4.48), whereas embryo freezing, type of stimulation protocol used, intracytoplasmic sperm injection fertilization, or zona removal did not influence its incidence.
Regimens combining pemetrexed (PEM) and immune checkpoint inhibitors (ICIs) targeting programmed cell death-1 (PD-1) or programmed death-ligand 1 (PD-L1) are widely used for the treatment of advanced ...non-squamous non-small-cell lung cancer (NSq-NSCLC). Recently, PEM was shown to induce immunogenic cell death (ICD) and to enhance immune-regulatory genes. Some patients demonstrate an extremely long-term response to PEM. It is possible that the continued response in these patients is dependent on not only the pharmacological induction of cytotoxic cell death but also antitumor immunity. However, factors that can predict outcomes associated with long-term PEM administration using blood test results have not yet been elucidated. We investigated the clinical characteristics and predictive factors in patients with advanced NSq-NSCLC who underwent long-term PEM maintenance therapy.
In total, 504 patients with advanced NSq-NSCLC who received PEM combination therapy/monotherapy (n = 414) or paclitaxel (PTX) combination therapy (n = 90) between January 2010 and November 2019 were recruited; 381 patients were retained for the final analysis. Patients treated with PEM (n = 301) were divided into subgroups according to the total cycles of PEM (≥ 17 n = 25 for the long-term administration group and ≤ 16 n = 276 for the intermediate/short-term group) and compared with another population (n = 80) treated with PTX combination regimen. We investigated clinical features and predictive biomarkers, focusing on immune-regulatory factors, absolute lymphocyte count (ALC), neutrophil-to-lymphocyte ratio (NLR), and PD-1 and PD-L1 expression, to predict long-term response to PEM.
The long-term PEM administration group exhibited a higher ALC and a lower NLR than the shorter-term group did. Both these markers displayed greater association with progression-free survival and overall survival in the PEM combination therapy group than in the PTX combination therapy group. Increased PD-1 lymphocytes were associated with the long-term PEM response group, as PD-L1 expression in tumors was associated with a high incidence of immune-related adverse effects following ICI administration.
ALC, NLR, and PD-1 expression are PEM-mediated predictive biomarkers that are indirectly related to tumor immunity and can provide useful predictive information on the long-term response to PEM in patients with NSq-NSCLC.
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