PAI-1 mediates acquired resistance to MET-targeted therapy in non-small cell lung cancer.

Mechanisms underlying primary and acquired resistance to MET tyrosine kinase inhibitors (TKIs) in managing non-small cell lung cancer remain unclear. In this study, we investigated the possible mechanisms acquired for crizotinib in MET-amplified lung carcinoma cell lines. Two MET-amplified lung cancer cell lines, EBC-1 and H1993, were established for acquired resistance to MET-TKI crizotinib and were functionally elucidated. Genomic and transcriptomic data were used to assess the factors contributing to the resistance mechanism, and the alterations hypothesized to confer resistance were validated. Multiple mechanisms underlie acquired resistance to crizotinib in MET-amplified lung cancer cell lines. In EBC-1-derived resistant cells, the overexpression of SERPINE1, the gene encoding plasminogen activator inhibitor-1 (PAI-1), mediated the drug resistance mechanism. Crizotinib resistance was addressed by combination therapy with a PAI-1 inhibitor and PAI-1 knockdown. Another mechanism of resistance in different subline cells of EBC-1 was evaluated as epithelial-to-mesenchymal transition with the upregulation of antiapoptotic proteins. In H1993-derived resistant cells, MEK inhibitors could be a potential therapeutic strategy for overcoming resistance with downstream mitogen-activated protein kinase pathway activation. In this study, we revealed the different mechanisms of acquired resistance to the MET inhibitor crizotinib with potential therapeutic application in patients with MET-amplified lung carcinoma.

Periostin secreted by cancer-associated fibroblasts promotes cancer progression and drug resistance in non-small cell lung cancer.

Cancer-associated fibroblasts (CAFs) are important components in the tumor microenvironment, and we sought to identify effective therapeutic targets in CAFs for non-small cell lung cancer (NSCLC). In this study, we established fibroblast cell lines from the cancerous and non-cancerous parts of surgical lung specimens from patients with NSCLC and evaluated the differences in behaviors towards NSCLC cells. RNA sequencing analysis was performed to investigate the differentially expressed genes between normal fibroblasts (NFs) and CAFs, and we identified that the expression of periostin (POSTN), which is known to be overexpressed in various solid tumors and promote cancer progression, was significantly higher in CAFs than in NFs. POSTN increased cell proliferation via NSCLC cells' ERK pathway activation and induced epithelial-mesenchymal transition (EMT), which improved migration in vitro. In addition, POSTN knockdown in CAFs suppressed these effects, and in vivo experiments demonstrated that the POSTN knockdown improved the sensitivity of EGFR-mutant NSCLC cells for osimertinib treatment. Collectively, our results showed that CAF-derived POSTN is involved in tumor growth, migration, EMT induction, and drug resistance in NSCLC. Targeting CAF-secreted POSTN could be a potential therapeutic strategy for NSCLC. KEY MESSAGES: • POSTN is significantly upregulated in CAFs compared to normal fibroblasts in NCSLC. • POSTN increases cell proliferation via activation of the NSCLC cells' ERK pathway. • POSTN induces EMT in NSCLC cells and improves the migration ability. • POSTN knockdown improves the sensitivity for osimertinib in EGFR-mutant NSCLC cells.

Surgical resection of a retroperitoneal liposarcoma producing insulin-like growth factor II: a case report.

BACKGROUND: Tumor-produced high molecular weight insulin-like growth factor-II (big insulin-like growth factor-II) is considered to cause non-islet cell tumor hypoglycemia. This paper presents a case of surgically resected retroperitoneal liposarcoma that produced big insulin-like growth factor-II. CASE PRESENTATION: Here, we report the case of a 62-year-old woman who presented with an abdominal mass and hypoglycemia. Non-islet cell tumor hypoglycemia due to retroperitoneal liposarcoma was suspected. After complete resection of the tumor, the patient's hypoglycemia improved and big insulin-like growth factor-II disappeared in the molecular weight analysis of serum insulin-like growth factor-II by western blotting. The patient had no tumor recurrence or reappearance of hypoglycemia 16 months after the operation without any adjuvant therapy. CONCLUSIONS: Although insulin-like growth factor-II-producing tumors are generally large and difficult to operate on, surgical resection is currently the most effective and only treatment; thus, it is essential to attempt resection aggressively.

Drug repositioning of tranilast to sensitize a cancer therapy by targeting cancer-associated fibroblast.

Cancer-associated fibroblasts (CAFs) are a major component of the tumor microenvironment that mediate resistance of cancer cells to anticancer drugs. Tranilast is an antiallergic drug that suppresses the release of cytokines from various inflammatory cells. In this study, we investigated the inhibitory effect of tranilast on the interactions between non-small cell lung cancer (NSCLC) cells and the CAFs in the tumor microenvironment. Three EGFR-mutant NSCLC cell lines, two KRAS-mutant cell lines, and three CAFs derived from NSCLC patients were used. To mimic the tumor microenvironment, the NSCLC cells were cocultured with the CAFs in vitro, and the molecular profiles and sensitivity to molecular targeted therapy were assessed. Crosstalk between NSCLC cells and CAFs induced multiple biological effects on the NSCLC cells both in vivo and in vitro, including activation of the STAT3 signaling pathway, promotion of xenograft tumor growth, induction of epithelial-mesenchymal transition (EMT), and acquisition of resistance to molecular-targeted therapy, including EGFR-mutant NSCLC cells to osimertinib and of KRAS-mutant NSCLC cells to selumetinib. Treatment with tranilast led to inhibition of IL-6 secretion from the CAFs, which, in turn, resulted in inhibition of CAF-induced phospho-STAT3 upregulation. Tranilast also inhibited CAF-induced EMT in the NSCLC cells. Finally, combined administration of tranilast with molecular-targeted therapy reversed the CAF-mediated resistance of the NSCLC cells to the molecular-targeted drugs, both in vitro and in vivo. Our results showed that combined administration of tranilast with molecular-targeted therapy is a possible new treatment strategy to overcome drug resistance caused by cancer-CAF interaction.

Clinical Features of Patients With Second Primary Lung Cancer After Head and Neck Cancer.

BACKGROUND: In survivors of head and neck cancer (HNC), second primary lung cancer (SPLC) often develop as a result of a common risk factor, that is, smoking. A multicenter experience was reviewed to evaluate how the history of a diagnosis of HNC affects the outcomes of patients undergoing pulmonary resection for SPLC. METHODS: A multicenter retrospective analysis of patients hospitalized between January 2012 and December 2018 was performed. From a cohort of 4521 patients undergoing therapeutic pulmonary resection for primary non-small cell lung cancer, 100 patients with a previous history of HNC (HNC group) were identified. These patients were compared with a control group consisting of 200 patients without an HNC history from the same cohort pair-matched with operating facility, age, sex, and pathologic stage of lung cancer. RESULTS: At the time of surgery for SPLC, the HNC group showed malnutrition with a lower prognostic nutritional index compared with the control group (P < .001). The HNC group was determined to have postoperative complications more frequently (P = .02). The 5-year overall survival rates in the HNC and control groups were 59.0% and 83.2%, respectively (P < .001). Statistically, HNC history, lower prognostic nutritional index, squamous cell lung cancer, and TNM stage were identified to be independently associated with poor survival. CONCLUSIONS: Patients with SPLC after primary HNC often present with malnutrition and are predisposed to postoperative complications and poor survival after pulmonary resection.

Survival and prognostic factors in patients undergoing pulmonary metastasectomy for lung metastases from retroperitoneal sarcoma.

BACKGROUND: Soft-tissue sarcomas are rare malignancies that consist of many different histologic subtypes and arise in various locations in the body. In patients with lung metastases from retroperitoneal sarcomas, the long-term outcomes and prognostic factors are unknown. This study is a retrospective review of patients undergoing pulmonary metastasectomy for retroperitoneal sarcoma metastases at one institution, with the purpose of determining prognostic factors and clinical outcomes. METHODS: This is a single-center, retrospective cohort study of patients undergoing pulmonary metastasectomy for lung metastases from various sarcomas at Okayama University Hospital from January 2006 to December 2018. The Kaplan-Meier method and log-rank test were used for the analyses, and cut-off values of continuous variables were determined by a receiver operating characteristic curve analysis. RESULTS: Twenty-four patients underwent the first pulmonary metastasectomy for lung metastases from retroperitoneal sarcoma in our hospital. Leiomyosarcoma was the most common histologic subtype of retroperitoneal sarcoma (79.2%, n = 19). Median overall survival was 49.9 months, and the 3-year and 5-year survival rates after the first pulmonary metastasectomy were 62.5% and 26.4% respectively. In univariate analysis, age ≥56 years, disease-free interval < 15 months, and size of metastasis (≥ 27 mm) were associated with poor survival. CONCLUSION: Pulmonary metastasectomy can be considered as an effective management strategy in retroperitoneal sarcoma patients with lung metastases in appropriately selected cases, just as it is for other sarcomas.

A case of infective endocarditis mimicking a large mesenteric abscess.

Infective endocarditis (IE) demonstrates a broad array of clinical presentations and complications. However, IE with prominent abdominal findings is uncommon. We encountered a case of IE caused by Staphylococcus aureus that presented a large mesenteric abscess and was initially diagnosed as an intra-abdominal infection. There are few reports of IE with mesenteric abscess formation. Even if an intra-abdominal abscess is the main symptom, the possibility that it is part of a systemic infection should be considered if the causative organism is atypical or if symptoms are present in multiple organs. Physicians should always be aware of the possibility that IE may mimic other diseases, including intra-abdominal infections.

The incidence and prognostic value of hypochloremia in critically ill patients.

Little is known on the clinical effects of chloride on critically ill patients. We conducted this retrospective, observational study in 488 critically ill patients to investigate the incidence of chloride abnormalities, effects of hypochloremia in acid-base disorders, and association between chloride and clinical outcome. The study involved retrieval of arterial blood gas analyses, biochemical and demographical data from electrical records as well as quantitative acid-base analyses. For statistical analysis, the patients were stratified into three groups according to their chloride level (normal range: 98-106 mEq/L). The distribution of chloride levels was hyperchloremia 16.6%, normochloremia 74.6%, and hypochloremia 8.8%. The hypochloremic group was significantly alkalemic (P < 0.0001) and has significantly higher apparent strong ion difference (SIDa) (P < 0.0001) compared to the two other groups. The hypochloremic group had significantly longer stays in the ICU and hospital (P < 0.0001) with higher mortality (P < 0.0001). However, multiple regression analysis showed that chloride was not an independent factor of poorer outcome. In conclusion, the acid-base characteristics of the hypochloremic patients were alkalemia coexisting with higher SIDa. And although it was not an independent prognostic factor, hypochloremia was related to poorer outcome in critically ill settings.