Immunogenicity after vaccination of COVID-19 vaccines in patients with cancer: a prospective, single center, observational study.

BACKGROUND: Patients with cancer, particularly those undergoing chemotherapy, are at risk from the low immunogenicity of Coronavirus Disease 19 (COVID-19) vaccines. METHODS: This prospective study assessed the seroconversion rate of COVID-19 vaccines among patients with cancer and hospital staff. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein-specific IgG (S-IgG) concentrations were evaluated before the first vaccination, and 1-3 and 4-6 months after the second vaccination. The primary endpoint was the seroconversion rate measured 1-3 months after the second vaccine. RESULTS: In total, 590 patients and 183 healthy hospital staff were analyzed. At 1-3 months after the second vaccination, the S-IgG antibody concentration exceeded the cut-off value (20 BAU/mL) in 96.1% (567/590) of the patients with cancer and 100% (183/183) of the healthy controls (p = 0.0024). At 4-6 months after the second vaccination, the S-IgG antibody concentration exceeded the cut-off value (20 BAU/ml for S-IgG) in 93.1% (461/495) of the patients with cancer and 100% (170/170) of the healthy controls (p < 0.0001). Old age, being male, and low lymphocyte count were related to low SARS-CoV-2 S-IgG levels 1-3 months after the second vaccination among patients, while body mass index, smoking history, and serum albumin level were not. Patients undergoing platinum combination therapy and alkylating agent among cytotoxic drugs, and PARP inhibitor, mTOR inhibitor, and BCR-ABL inhibitor exhibited a low S-IgG antibody concentration compared to the no treatment group. CONCLUSIONS: COVID-19 vaccine immunogenicity was reduced among patients with cancer, especially under several treatment regimens.

Tumor microenvironment-mediated immune profiles and efficacy of anti-PD-L1 antibody plus chemotherapy stratified by DLL3 expression in small-cell lung cancer.

BACKGROUND: Delta-like ligand 3 (DLL3) is a therapeutic target in small-cell lung cancer (SCLC). However, how DLL3 expression status affects the tumor microenvironment (TME) and clinical outcomes in SCLC remains unclear. METHODS: This retrospective study included patients with postoperative limited-stage (LS)-SCLC and extensive-stage (ES)-SCLC treated with platinum and etoposide (PE) plus anti-programmed cell death ligand 1 (PD-L1) antibody. We investigated the relationship of DLL3 expression with TME, mutation status, tumor neoantigens, and immunochemotherapy. RESULTS: In the LS-SCLC cohort (n = 59), whole-exome sequencing revealed that DLL3High cases had significantly more neoantigens (P = 0.004) and a significantly higher rate of the signature SBS4 associated with smoking (P = 0.02) than DLL3Low cases. Transcriptome analysis in the LS-SCLC cohort revealed that DLL3High cases had significantly suppressed immune-related pathways and dendritic cell (DC) function. SCLC with DLL3High had significantly lower proportions of T cells, macrophages, and DCs than those with DLL3Low. In the ES-SCLC cohort (n = 30), the progression-free survival associated with PE plus anti-PD-L1 antibody was significantly worse in DLL3High cases than in DLL3Low cases (4.7 vs. 7.4 months, P = 0.01). CONCLUSIONS: Although SCLC with DLL3High had a higher neoantigen load, these tumors were resistant to immunochemotherapy due to suppressed tumor immunity by inhibiting antigen-presenting functions.

Clinicopathological characteristics and molecular analysis of lung cancer associated with ciliated muconodular papillary tumor/bronchiolar adenoma.

Ciliated muconodular papillary tumor/bronchiolar adenoma (CMPT/BA) is a recently introduced benign lung tumor. It remains unclear whether CMPT/BA is associated with a specific type of lung cancer (LC). We studied the clinicopathological characteristics and genetic profiles of the coexisting primary LC and CMPT/BA (LCCM) cases. We identified eight LCCM (0.4%) from the resected Stage 0-III primary LC (n = 1945). The LCCM cohort was male-dominant (n = 8), elderly (median 72 years old), and most were smokers (n = 6). In addition to the adenocarcinoma (n = 8), we detected two squamous cell carcinomas and one small cell carcinoma-in some cases, multiple cancer. The target sequence/whole exome sequence (WES) revealed no shared mutations between CMPT/BA and LC. One exceptional case was invasive mucinous adenocarcinoma harboring an HRAS mutation (I46N, c.137T>A), but it was likely to be a single nucleotide polymorphism based on variant allele frequency (VAF). Other driver mutations in LC included EGFR (InDel, n = 2), BRAF(V600E) (n = 1), KRAS (n = 2), GNAS (n = 1), and TP53 (n = 2). BRAF(V600E) was the most frequent mutation in CMPT/BA (60%). In contrast, LC showed no specific trend in driver gene mutations. In conclusion, our study revealed differences in the gene mutation profiles of CMPT/BA and LC in coexisting cases, suggesting mostly independent clonal tumorigenesis of CMPT/BA from LC.

Prognostic significance of cachexia in advanced non-small cell lung cancer patients treated with pembrolizumab.

BACKGROUND: Cancer cachexia is a multifactorial syndrome characterized by weight loss leading to immune dysfunction that is commonly observed in patients with advanced non-small cell lung cancer (NSCLC). We examined the impact of cachexia on the prognosis of patients with advanced NSCLC receiving pembrolizumab and evaluated whether the pathogenesis of cancer cachexia affects the clinical outcome. PATIENTS AND METHODS: Consecutive patients with advanced NSCLC treated with pembrolizumab were retrospectively enrolled in the study. Serum levels of pro-inflammatory cytokines and appetite-related hormones, which are related to the pathogenesis of cancer cachexia, were analyzed. Cancer cachexia was defined as (1) a body weight loss > 5% over the past 6 months, or (2) a body weight loss > 2% in patients with a body mass index < 20 kg/m2. RESULTS: A total of 133 patients were enrolled. Patients with cachexia accounted for 35.3%. No significant difference in the objective response rate was seen between the cachexia and non-cachexia group (29.8% vs. 34.9%, P = 0.550), but the median progression-free survival (PFS) and overall survival (OS) periods were significantly shorter in the cachexia group than in the non-cachexia group (PFS: 4.2 months vs. 7.1 months, P = 0.04, and OS: 10.0 months vs. 26.6 months, P = 0.03). The serum TNF-alpha, IL-1 alpha, IL-8, IL-10, and leptin levels were significantly associated with the presence of cachexia, but not with the PFS or OS. CONCLUSION: The presence of cachexia was significantly associated with poor prognosis in advanced NSCLC patients receiving pembrolizumab, not with the response to pembrolizumab.

Augmented Clearance of Nivolumab Is Associated with Renal Functions in Chronic Renal Disease Model Rats.

The clinically approved dose of nivolumab is 240 mg every 2 weeks. However, previous studies have shown that baseline nivolumab clearance (CL) is associated with treatment outcomes in patients with solid cancers, thus motivating researchers to identify prognostic factors and indices influencing nivolumab CL. This study used chronic kidney disease model rats to investigate whether chronic renal impairment affected nivolumab CL and explored the surrogate markers associated with nivolumab CL. We observed that the total CL for nivolumab (CLtot) was approximately 1.42 times higher in chronic kidney disease model rats than that in sham rats with an increased urinary excretion. Additionally, CLtot showed positive correlation with renal CL for nivolumab (CLR) but not with extrarenal CL. Furthermore, the baseline levels of creatinine, blood urea nitrogen, creatinine CL, and urinary albumin/creatine ratio based on laboratory data were also significantly correlated with CLR Our findings suggest that nivolumab CL increases as renal function deteriorates because of an increased excretion of nivolumab in the urine; additionally, laboratory data reflecting renal function may be a feasible index to qualitatively estimate nivolumab CL prior to nivolumab treatment under conditions of renal impairment. SIGNIFICANCE STATEMENT: This study demonstrated that nivolumab was rapidly eliminated from the circulation in chronic kidney disease model rats compared with sham rats with an increased urinary nivolumab excretion. Moreover, nivolumab clearance was significantly correlated with the baseline levels of certain laboratory parameters reflecting renal functions. These results indicate the potential applicability of baseline renal function as a prognostic index to qualitatively estimate nivolumab clearance prior to nivolumab treatment under conditions with renal impairment.

Development of an optimal protocol for molecular profiling of tumor cells in pleural effusions at single-cell level.

Liquid biopsy analyzes the current status of primary tumors and their metastatic regions. We aimed to develop an optimized protocol for single-cell sequencing of floating tumor cells (FTCs) in pleural effusion as a laboratory test. FTCs were enriched using a negative selection of white blood cells by a magnetic-activated cell sorting system, and CD45-negative and cytokeratin-positive selection using a microfluidic cell separation system with a dielectrophoretic array. The enriched tumor cells were subjected to whole-genome amplification (WGA) followed by genome sequencing. The FTC analysis detected an EGFR exon 19 deletion in Case 1 (12/19 cells, 63.2%), and EML4-ALK fusion (17/20 cells, 85%) with an alectinib-resistant mutation of ALK (p.G1202R) in Case 2. To eliminate WGA-associated errors and increase the uniformity of the WGA product, the protocol was revised to sequence multiple single FTCs individually. An analytical pipeline, accurate single-cell mutation detector (ASMD), was developed to identify somatic mutations of FTCs. The large numbers of WGA-associated errors were cleaned up, and the somatic mutations detected in FTCs by ASMD were concordant with those found in tissue specimens. This protocol is applicable to circulating tumor cells analysis of peripheral blood and expands the possibility of utilizing molecular profiling of cancers.

Characterization of the large-scale Japanese patient-derived xenograft (J-PDX) library.

The use of patient-derived xenografts (PDXs) has recently attracted attention as a drug discovery platform with a high predictive clinical efficacy and a preserved tumor heterogeneity. Given the racial differences in genetic variations, it would be desirable to establish a PDX library from Japanese cancer patients on a large scale. We thus tried to construct the Japanese PDX (J-PDX) library with a detailed clinical information for further clinical utilization. Between August 2018 and May 2020, a total of 1126 cancer specimens from 1079 patients were obtained at the National Cancer Center Hospital and National Cancer Center Hospital East, Japan, and were immediately transplanted to immunodeficient mice at the National Cancer Center Research Institute. A total of 298 cross-cancer PDXs were successfully established. The time to engraftment varied greatly by cancer subtypes, especially in the first passage. The engraftment rate was strongly affected by the clinical stage and survival time of the original patients. Approximately 1 year was needed from tumor collection to the time when coclinical trials were conducted to test the clinical utility. The 1-year survival rates of the patients who were involved in establishing the PDX differed significantly, from 95.6% for colorectal cancer to 56.3% for lung cancer. The J-PDX library consisting of a wide range of cancer subtypes has been successfully established as a platform for drug discovery and development in Japan. When conducting coclinical trials, it is necessary to consider the target cancer type, stage, and engraftment rate in light of this report.

Chaperone-mediated autophagy receptor modulates tumor growth and chemoresistance in non-small cell lung cancer.

Chaperone-mediated autophagy (CMA) is a lysosomal degradation pathway of selective soluble proteins. Lysosome-associated membrane protein type 2a (LAMP2A) is the key receptor protein of CMA; downregulation of LAMP2A leads to CMA blockade. Although CMA activation has been involved in cancer growth, CMA status and functions in non-small cell lung cancer (NSCLC) by focusing on the roles in regulating chemosensitivity remain to be clarified. In this study, we found that LAMP2A expression is elevated in NSCLC cell lines and patient's tumors, conferring poor survival and platinum resistance in NSCLC patients. LAMP2A knockdown in NSCLC cells suppressed cell proliferation and colony formation and increased the sensitivity to chemotherapeutic drugs in vitro. Furthermore, we found that intrinsic apoptosis signaling is the mechanism of cell death involved with CMA blockade. Remarkably, LAMP2A knockdown repressed tumorigenicity and sensitized the tumors to cisplatin treatment in NSCLC-bearing mice. Our discoveries suggest that LAMP2A is involved in the regulation of cancer malignant phenotypes and represents a promising new target against chemoresistant NSCLC.

Dasatinib Suppresses TGFß-Mediated Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells and Inhibits Pulmonary Fibrosis.

PURPOSE: Transforming growth factor ß (TGFß)-mediated epithelial-mesenchymal transition (EMT) of alveolar epithelial cells contributes to pulmonary fibrosis. Dasatinib (DAS), a potent and broad-spectrum tyrosine kinase inhibitor, has been widely studied as an anti-cancer agent. However, the therapeutic application of DAS for pulmonary fibrosis has not been clarified. Our purpose here is to investigate the effect of DAS on TGFß1-induced EMT in human alveolar and bronchial epithelial cells in vitro and to evaluate the efficacy of DAS on lung fibrosis in vivo. METHODS: TGFß1-stimulated human alveolar epithelial (A549) and bronchial epithelial (BEAS-2B) cells were treated with or without DAS in vitro. Murine pulmonary fibrosis model was generated by injection of bleomycin (BLM). RESULTS: A549 and BEAS-2B cells exposed to TGFß1 underwent EMT, as indicated by downregulation of epithelial protein E-cadherin and induction of the mesenchymal proteins, fibronectin and type I and type IV collagen. These effects were dramatically suppressed by DAS treatment, which also prevented Smad2 and Smad3 phosphorylation. DAS inhibited TGFß1-induced cell motility and migration. Furthermore, DAS administration significantly attenuated lung fibrosis in mice by histological analysis. Treatment with DAS also significantly reduced the levels of collagen and fibronectin and phosphorylation of Smad2 in the lung tissues of the murine model. CONCLUSIONS: These findings suggest that DAS inhibited TGFß-mediated EMT of alveolar and bronchial epithelial cells and attenuated BLM-induced lung fibrosis in mice by suppressing the TGFß/Smad pathway. DAS may be a promising and novel anti-fibrotic agent for preventing lung fibrosis.

Sensitive cytometry based system for enumeration, capture and analysis of gene mutations of circulating tumor cells.

Methods for the enumeration and molecular characterization of circulating tumor cells (CTC) have been actively investigated. However, such methods are still technically challenging. We have developed a novel epithelial cell adhesion molecule independent CTC enumeration system integrated with a sorting system using a microfluidics chip. We compared the number of CTC detected using our system with those detected using the CellSearch system in 46 patients with various cancers. We also evaluated epidermal growth factor receptor (EGFR) and PIK3CA mutations of captured CTC in a study of 4 lung cancer and 4 breast cancer patients. The percentage of samples with detected CTC was significantly higher with our system (65.2%) than with CellSearch (28.3%). The number of detected CTC per patient using our system was statistically higher than that using CellSearch (median 5, 0; P = 0.000172, Wilcoxon test). In the mutation analysis study, the number of detected CTC per patient was low (median for lung, 4.5; median for breast, 5.5); however, it was easy to detect EGFR and PIK3CA mutations in the CTC of 2 lung and 1 breast cancer patient, respectively, using a commercially available kit. Our system is more sensitive than CellSearch in CTC enumeration of various cancers and is also capable of detecting EGFR and PIK3CA mutations in the CTC of lung and breast cancer patients, respectively.

Oct4 plays a crucial role in the maintenance of gefitinib-resistant lung cancer stem cells.

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.

The clinical relevance of the miR-197/CKS1B/STAT3-mediated PD-L1 network in chemoresistant non-small-cell lung cancer.

Programmed cell death ligand-1 (PD-L1) has recently gained considerable attention for its role in tumor immune escape. Here, we identify a miR-197/CKS1B/STAT3-mediated PD-L1 network in chemoresistant non-small-cell lung cancer (NSCLC), independent of immunoinhibitory signals. miR-197 is downregulated in platinum-resistant NSCLC specimens, resulting in the promotion of chemoresistance, tumorigenicity, and pulmonary metastasis in vitro and in vivo. Mechanistic investigations reveal that a miR-197-mediated CKS1B/STAT3 axis exerts tumor progression regulated by various oncogenic genes (Bcl-2, c-Myc, and cyclin D1), and PD-L1 is a putative biomarker of this axis. Furthermore, we demonstrate that a miR-197 mimic sensitizes PD-L1(high) drug-resistant cells to chemotherapy. These results indicate that the biological interaction between PD-L1 and chemoresistance occurs through the microRNA regulatory cascade. More importantly, expression levels of miR-197 are inversely correlated with PD-L1 expression (n = 177; P = 0.026) and are associated with worse overall survival (P = 0.015). Our discoveries suggest that the miR-197/CKS1B/STAT3-mediated network can drive tumor PD-L1 expression as a biomarker of this cascade, and miR-197 replacement therapy may be a potential treatment strategy for chemoresistant NSCLC.

Impact of KRAS mutation on response and outcome of patients with stage III non-squamous non-small cell lung cancer.

The frequency and clinical profile of patients with stage III non-small cell lung cancer harboring KRAS mutations have not yet been well documented. Here, we analyzed hotspot KRAS mutations using high-resolution melting analyses in tumor specimens from patients who received chemoradiotherapy between January 2001 and December 2010 at the National Cancer Center Hospital. The associations between the presence of KRAS mutations and the response rate, relapse-free survival, first relapse sites, survival post-progression and overall survival were investigated. A total of 274 non-squamous non-small cell lung cancer patients received chemoradiotherapy at our hospital. After excluding 121 patients for whom tumor specimens were not available and 34 patients with EGFR mutations, the remaining 119 patients were included in the analysis. KRAS mutations were found at a frequency of 13%. Patients with KRAS mutations had a shorter median relapse-free survival (6.1 vs 10.9 months) and a lower response rate (63% vs 81%). As for the first relapse site, patients with KRAS mutations had fewer local relapses (8% vs 23%) and more brain metastases (46% vs 12%). After disease progression, patients with KRAS mutations had a significantly shorter median survival post-progression (2.5 vs 7.3 months, P = 0.028) and median overall survival (15.1 vs 29.1 months, P = 0.022). Our results suggested that KRAS mutation could be associated with a reduced efficacy of chemoradiotherapy and a shortened survival time.

Phase I study of ipilimumab in phased combination with paclitaxel and carboplatin in Japanese patients with non-small-cell lung cancer.

BACKGROUND: Ipilimumab is an antibody that targets the cytotoxic T-lymphocyte antigen-4 to potentiate an antitumor response. Adding ipilimumab 10 mg/kg to paclitaxel (PTX) and carboplatin (CBDCA) in a phased schedule improved progression-free survival in a phase II non-small-cell lung cancer (NSCLC) study. METHODS: This dose-escalating, phase I study was designed to identify the recommended dose of ipilimumab (3 or 10 mg/kg) by evaluating dose-limiting toxicity (DLT; Cycles 3 and 4) in phased combination with PTX (175 mg/m(2)) and CBDCA (area under the curve = 6) in Japanese patients with advanced NSCLC. Treatment was administered intravenously every 3 weeks initially, followed by some eligible patients receiving maintenance ipilimumab once every 12 weeks. Additional endpoints included safety, tumor response, pharmacokinetics, and immunogenicity. RESULTS: Fifteen patients were enrolled and 12 received ipilimumab (n = 6, 3 mg/kg; n = 6, 10 mg/kg) in combination with PTX and CBDCA. DLTs occurred in 2 patients (ipilimumab 3 mg/kg) and 1 patient (ipilimumab 10 mg/kg). The most common grade 3/4 adverse events (AEs) were decreased hemoglobin, leukopenia, and neutropenia. The most common immune-related AEs affected the skin, gastrointestinal, and nervous system. The safety profile was similar in both cohorts. Three patients in each cohort achieved a partial response. The pharmacokinetic (PK) profile of ipilimumab in Japanese patients was similar to that observed in previous studies in non-Japanese patients. Conclusions The recommended dose of ipilimumab in phased combination with PTX and CBDCA in Japanese patients with NSCLC was identified as 10 mg/kg. The safety profile was consistent with the previously defined AE profile.

Treatment with insulin-like growth factor 1 receptor inhibitor reverses hypoxia-induced epithelial-mesenchymal transition in non-small cell lung cancer.

Insulin-like growth factor 1 receptor (IGF1R) is expressed in many types of solid tumors including non-small cell lung cancer (NSCLC), and enhanced activation of IGF1R is thought to reflect cancer progression. Epithelial-mesenchymal transition (EMT) has been established as one of the mechanisms responsible for cancer progression and metastasis, and microenvironment conditions, such as hypoxia, have been shown to induce EMT. The purposes of this study were to address the role of IGF1R activation in hypoxia-induced EMT in NSCLC and to determine whether inhibition of IGF1R might reverse hypoxia-induced EMT. Human NSCLC cell lines A549 and HCC2935 were exposed to hypoxia to investigate the expression of EMT-related genes and phenotypes. Gene expression analysis was performed by quantitative real-time PCR and cell phenotypes were studied by morphology assessment, scratch wound assay, and immunofluorescence. Hypoxia-exposed cells exhibited a spindle-shaped morphology with increased cell motility reminiscent of EMT, and demonstrated the loss of E-cadherin and increased expression of fibronectin and vimentin. Hypoxia also led to increased expression of IGF1, IGF binding protein-3 (IGFBP3), and IGF1R, but not transforming growth factor ß1 (TGFß1). Inhibition of hypoxia-inducible factor 1α (HIF1α) with YC-1 abrogated activation of IGF1R, and reduced IGF1 and IGFBP3 expression in hypoxic cells. Furthermore, inhibition of IGF1R using AEW541 in hypoxic condition restored E-cadherin expression, and reduced expression of fibronectin and vimentin. Finally, IGF1 stimulation of normoxic cells induced EMT. Our findings indicated that hypoxia induced EMT in NSCLC cells through activation of IGF1R, and that IGF1R inhibition reversed these phenomena. These results suggest a potential role for targeting IGF1R in the prevention of hypoxia-induced cancer progression and metastasis mediated by EMT.

Adjuvant chemotherapy in patients with completely resected small cell lung cancer: a retrospective analysis of 26 consecutive cases.

OBJECTIVE: Several clinical studies have demonstrated the efficacy and safety of adjuvant chemotherapy in patients with completely resected small cell lung cancer for a selected limited stage. However, it is unclear whether adjuvant chemotherapy is feasible in clinical practice. The objective of this study was to analyze the efficacy and safety of adjuvant chemotherapy for small cell lung cancer patients retrospectively in clinical practice. METHODS: From January 2002 to March 2012, 56 small cell lung cancer patients underwent surgery as initial therapy in our institute. Of these, 26 patients received adjuvant chemotherapy. The clinical data of patients who received adjuvant chemotherapy were retrospectively analyzed. RESULTS: The chemotherapy regimens were cisplatin and irinotecan in 16 patients, cisplatin and etoposide in 1 and carboplatin and etoposide in 9. Median follow-up time was 44.8 months. Nineteen (73%) patients received the full course of chemotherapy. Median recurrence-free survival was 21.4 months. Median survival time was not reached. There was no treatment-related death. CONCLUSION: Adjuvant chemotherapy may be generally safe and efficacious in selected small cell lung cancer patients.

Secondary osteosarcoma developing 10 years after chemoradiotherapy for non-small-cell lung cancer.

A 53-year-old female patient was admitted with pain and a progressively enlarging mass in the right upper chest. Chest computed tomography revealed a mass lesion in the region of the right upper ribs. Ten years prior to this admission, the patient had undergone right lobectomy for lung adenocarcinoma. One year after the surgery, follow-up computed tomography had revealed tumor recurrence in the mediastinal and supraclavicular lymph nodes, and the patient had been treated by chemoradiotherapy. Thereafter, regular follow-up had revealed no evidence of recurrence of the non-small-cell lung cancer. Histopathological findings revealed proliferation of spindle-shaped malignant tumor cells in a background of osteoid, consistent with the diagnosis of osteosarcoma. The location of the tumor was consistent with the radiation field. Based on the clinicopathological findings, the patient was diagnosed as having secondary osteosarcoma occurring as a result of the chemoradiotherapy administered previously for the recurrent non-small-cell lung cancer. Unfortunately, the patient died of rapid progression of the osteosarcoma within a week of admission to the hospital. The autopsy revealed contiguous invasion by the tumor of the heart, with massive thrombus formation. The peripheral pulmonary arteries were diffusely occluded by metastatic tumors. Our case serves to highlight the risk of development of secondary sarcoma as a life-threatening late complication after chemoradiotherapy for locally advanced non-small-cell lung cancer, even after complete cure of the primary tumor.

Rapid Response to Lenvatinib and Disease Flare After Discontinuation in a Patient With Thymic Carcinoma Harboring KIT Exon 11 Mutation: A Case Report.

Lenvatinib, a multitarget tyrosine kinase inhibitor for c-Kit and other kinases, has exhibited promising efficacy in treating advanced or metastatic thymic carcinoma (TC). Here, we present the case of a patient with metastatic TC harboring a KIT exon 11 deletion and amplification. The patient exhibited a remarkable response to lenvatinib but experienced rapid disease progression after discontinuation of lenvatinib, referred to as a "disease flare." This case report indicates that KIT mutations and amplification can predict lenvatinib response in patients with TC. However, in such cases, there might be a risk of disease flares after lenvatinib discontinuation.

A molecular glue RBM39-degrader induces synthetic lethality in cancer cells with homologous recombination repair deficiency.

E7820 and Indisulam (E7070) are sulfonamide molecular glues that modulate RNA splicing by degrading the splicing factor RBM39 via ternary complex formation with the E3 ligase adaptor DCAF15. To identify biomarkers of the antitumor efficacy of E7820, we treated patient-derived xenograft (PDX) mouse models established from 42 patients with solid tumors. The overall response rate was 38.1% (16 PDXs), and tumor regression was observed across various tumor types. Exome sequencing of the PDX genome revealed that loss-of-function mutations in genes of the homologous recombination repair (HRR) system, such as ATM, were significantly enriched in tumors that responded to E7820 (p = 4.5 × 103). Interestingly, E7820-mediated double-strand breaks in DNA were increased in tumors with BRCA2 dysfunction, and knockdown of BRCA1/2 transcripts or knockout of ATM, ATR, or BAP1 sensitized cancer cells to E7820. Transcriptomic analyses revealed that E7820 treatment resulted in the intron retention of mRNAs and decreased transcription, especially for HRR genes. This induced HRR malfunction probably leads to the synthetic lethality of tumor cells with homologous recombination deficiency (HRD). Furthermore, E7820, in combination with olaparib, exerted a synergistic effect, and E7820 was even effective in an olaparib-resistant cell line. In conclusion, HRD is a promising predictive biomarker of E7820 efficacy and has a high potential to improve the prognosis of patients with HRD-positive cancers.