Real Clinical Practice of Combined Atezolizumab Plus Chemotherapy in Patients With Small Cell Lung Cancer.

BACKGROUND/AIM: Atezolizumab, an anti-PD-L1 antibody, has been increasingly administered in combination with chemotherapy to patients with small cell lung cancer (SCLC). This study aimed to determine how patients with extensive disease (ED) -SCLC responded to atezolizumab with chemotherapy and found factors affecting long-term response and survival. PATIENTS AND METHODS: This study focused on patients with SCLC who were treated with a combination of atezolizumab and chemotherapy in Japan between 2019 and 2023. Patient information and tumor response were analyzed, along with adverse events. We compared data and estimated survival probabilities. RESULTS: In our clinical trial, 95 patients with SCLC who received this treatment had a median progression-free survival of 6.0 months and a median overall survival of 15.0 months. Immune-related adverse events were observed in 13.7% of the patients, with grade 3 or higher in 5.3%. The efficacy and immune-related adverse events associated with this treatment regimen were comparable to those reported in previous clinical trials. Progression-free survival >2 years was observed in a small number of patients (5.3%). CONCLUSION: Our research will offer important insights for the future care of patients with extensive-stage SCLC by utilizing atezolizumab in combination with chemotherapy. Accumulation and confirmation of clinical practice results will have important implications for the future implementation of this therapy.

Atezolizumab for EGFR-mutated Non-small Cell Lung Cancer Patients: An Observation Study in Ibaraki Group (ATTENTION-IBARAKI).

BACKGROUND/AIM: Atezolizumab, an anti-programed death-ligand 1 monoclonal antibody, targets programed death-ligand 1 expressed on cancer cells and antigen-presenting cells and is now commonly used in combination with chemotherapy. We conducted a study to clarify the efficacy of atezolizumab in epidermal growth factor receptor (EGFR)-mutated patients who are considered less responsive to immune checkpoint inhibitors. PATIENTS AND METHODS: A retrospective review of patients with advanced non-small cell lung cancer (NSCLC) who received atezolizumab-containing therapy at 11 hospitals from April 2018 to March 2023 was performed. RESULTS: Median progression-free survival and overall survival in 33 EGFR-mutated patients treated with atezolizumab monotherapy were 2.0 and 9.0 months, respectively, and those in 19 patients who received combined atezolizumab plus chemotherapy were 12.0 and 17.0 months, respectively. When comparing EGFR-mutated and EGFR-negative patients after propensity score matching, there were no significant differences in progression-free survival and overall survival between the two groups, whether atezolizumab monotherapy or combined atezolizumab plus chemotherapy. Among EGFR-mutated patients, being male was a significant favorable factor in both atezolizumab treatment groups. None of the EGFR-mutated patients had grade 5 immune-related adverse events. CONCLUSION: Efficacy of atezolizumab in EGFR-mutated NSCLC patients could be comparable to that for EGFR-negative patients. To prolong the survival of EGFR-mutated NSCLC patients, appropriate selection and sequencing of EGFR for tyrosine kinase inhibitors, as well as immune checkpoint inhibitors, anti-tumor agents, and anti-angiogenic agents are important.

Atezolizumab Monotherapy for Non-small Cell Lung Cancer Patients: An Observational Study in Ibaraki Group (ATTENTION-IBARAKI).

BACKGROUND/AIM: Atezolizumab is a monoclonal antibody that targets programmed death-ligand 1 (PD-L1) expressed on cancer cells derived from various organs and antigen-presenting cells and is currently commonly used in combination with chemotherapy. We conducted a study to clarify the current status of response to atezolizumab monotherapy in clinical practice and clarify the factors that contribute to long-term response and survival. PATIENTS AND METHODS: We conducted a retrospective review of patients with advanced non-small cell lung cancer (NSCLC) treated with atezolizumab monotherapy from April 2018 to March 2023 at 11 Hospitals. RESULTS: The 147 patients evaluated had a progression-free survival (PFS) of 3.0 months and an overall survival of 7.0 months. Immune-related adverse events of any grade were observed in 13 patients (8.8%), grade 3 or higher in nine patients (6.1%), and grade 5 with pulmonary toxicity in one patient (0.7%). Favorable factors related to PFS were 'types of NSCLC other than adenocarcinoma'. Favorable factors for overall survival were 'performance status 0-1' and 'treatment lines up to 3'. There were 16 patients (10.9%) with PFS >1 year. No characteristic clinical findings were found in these 16 patients compared to the remaining 131 patients. CONCLUSION: Efficacy and immune-related adverse events of NSCLC patients associated with atezolizumab monotherapy were comparable to those of previous clinical trial results. Knowledge of characteristics of patients who are most likely to benefit from atezolizumab monotherapy is a crucial step towards implementing appropriate prescribing.

Prognostic Implication of PD-L1 Expression on Osimertinib Treatment for EGFR-mutated Non-small Cell Lung Cancer.

BACKGROUND/AIM: Real-world data on the clinical outcomes of first-line osimertinib treatment for non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations is lacking. This study aimed to reveal the treatment outcomes and prognostic factors of osimertinib as first-line therapy in clinical practice settings. PATIENTS AND METHODS: We retrospectively evaluated clinical outcomes of patients with EGFR-mutated NSCLC treated with osimertinib as first-line therapy across 12 institutions in Japan between August 2018 and March 2020. RESULTS: Among 158 enrolled patients, the objective response rate (ORR) was 68%, and the estimated median progression-free survival (PFS) was 17.1 months [95% confidence interval (CI)=14.5-19.7]. Subgroup analysis showed that PFS in the group with high programmed death-ligand 1 (PD-L1) expression was significantly shorter than that in groups with low or no PD-L1 expression (10.1 vs. 16.1 vs. 19.0 months; p=0.03). Univariate and multivariate analyses demonstrated that high PD-L1 expression was the only independent adverse prognostic factor of osimertinib outcome related to PFS (hazard ratio=2.71; 95%CI=1.26-5.84; p=0.01). In terms of anti-tumor response, there was no statistically significant correlation between PD-L1 expression and the ORR (67% vs. 76% vs. 65%; p=0.51). No significant correlation was also found between PD-L1 and the incidence of de novo resistance to osimertinib (p=0.39). CONCLUSION: Although PD-L1 expression was not associated with either the ORR or frequency of de novo resistance, high PD-L1 expression could be an independent adverse prognostic factor related to PFS in osimertinib treatment.

Bacterial triacylglycerol lipase is a potential cholesterol esterase: Identification of a key determinant for sterol-binding specificity.

Cholesterol esterase (Che) from Burkholderia stabilis (BsChe) is a homolog of well-characterized and industrially relevant bacterial triacylglycerol lipases (Lips). BsChe is a rare bacterial Lip enzyme that exhibits practical Che activity and is currently used in clinical applications to determine total serum cholesterol levels. To investigate the sterol specificity of BsChe, we determined the X-ray structure of BsChe. We discovered a local structural change in the active-site cleft, which might be related to substrate binding and product release. We also performed molecular docking studies by using the X-ray models of BsChe and cholesterol linoleate (CLL), the most favorable substrate for BsChe. The results showed that the sterol moieties of reasonable CLL docking poses localized to a specific active-site cleft surface formed by Leu266 and Ile287, which are unconserved among Burkholderia Lip homologs. Site-directed mutagenesis identified these residues as essential for the Che activity of BsChe, and Leu or Ile substitution conferred marked Che activity to Burkholderia Lips. In particular, Burkholderia cepacia and Burkholderia ubonensis Lips with the V266L/L287I double mutation exhibited ~50-fold and 500-fold higher Che activities than those of the wild-type enzymes, respectively. These results provide new insights into the substrate-binding mechanisms and selectivities of bacterial Lips.

Koleobacter methoxysyntrophicus gen. nov., sp. nov., a novel anaerobic bacterium isolated from deep subsurface oil field and proposal of Koleobacteraceae fam. nov. and Koleobacterales ord. nov. within the class Clostridia of the phylum Firmicutes.

An anaerobic thermophilic, rod-shaped bacterium possessing a unique non-lipid sheathed-like structure enveloping a single-membraned cell, designated strain NRmbB1T was isolated from at the deep subsurface oil field located in Yamagata Prefecture, Japan. Growth occurred with 40-60°C (optimum, 55°C), 0-2% (2%), NaCl and pH 6.0-8.5 (8.0). Fermentative growth with various sugars was observed. Glucose-grown cells generated acetate, hydrogen, pyruvate and lactate as the main end products. Syntrophic growth occurred with glucose, pyruvate and 3,4,5-trimethoxybenzoate in the presence of an H2-scavenging partner, and growth on 3,4,5-trimethoxybenzoate was only observed under syntrophic condition. The predominant cellular fatty acids were C16:0, iso-C16:0, anteiso-C15:0, and iso-C14:0. Respiratory quinone was not detected. The genomic G+C content was 40.8mol%. Based on 16S rRNA gene phylogeny, strain NRmbB1T belongs to a distinct order-level clade in the class Clostridia of the phylum Firmicutes, sharing low similarity with other isolated organisms (i.e., 87.5% for top hit Moorella thermoacetica DSM 2955T). In total, chemotaxonomic, phylogenetic and genomic characterization revealed that strain NRmbB1T (=KCTC 25035T, =JCM 39120T) represents a novel species of a new genus. In addition, we also propose the associated family and order as Koleobacteraceae fam. nov and Koleobacterales ord. nov., respectively.

Treatment of Patients With Non-small-cell Lung Cancer With Uncommon EGFR Mutations in Clinical Practice.

BACKGROUND/AIM: To describe real clinical outcomes in patients with non-small cell lung cancer who have uncommon epidermal growth factor receptor (EGFR) mutations. MATERIALS AND METHODS: We performed a retrospective chart review from 15 medical institutes that cover a population of three million people from April 2008 to March 2019. RESULTS: There were 102 patients with uncommon EGFR mutation. Progression-free survival (PFS) tended to be longer in patients receiving afatinib compared with first-generation EGFR tyrosine kinase inhibitors. PFS in patients treated with afatinib or osimertinib was significantly longer than in patients treated with gefitinib or erlotinib (p=0.030). Multivariate analysis also revealed the contribution of afatinib or osimertinib to increased survival. In patients with exon 20 insertions, chemotherapy was efficacious. CONCLUSION: In treating patients with uncommon EGFR mutations, our results indicate longer-term survival might be achieved with second-generation or later TKIs and cytotoxic chemotherapeutic drugs.

Clinicopathological Features in Elderly ALK-rearranged Non-small Cell Lung Cancer Patients.

AIM: To clarify the clinicopathological features in elderly anaplastic lymphoma kinase (ALK) rearranged non-small cell lung cancer (NSCLC) patients. PATIENTS AND METHODS: A retrospective study was performed in 129 ALK rearranged NSCLC patients diagnosed between April 2008 and March 2019 in fifteen Institutions of the Ibaraki prefecture, Japan. RESULTS: Median age of patients was 63 years. In 59 patients aged 65 and older, the proportions of patients with advanced stage and those treated with ALK-tyrosine kinase inhibitor (TKI) were lower than those younger than 65 years. There was no difference in overall survival (OS) between the two age groups. Among the elderly patients, no difference was observed in OS between the patients aged 65-69 and those aged 70 and older. In 89 patients treated with TKI, no significant differences were observed in the progression-free survival of TKIs and OS between patients aged 65 and older and those younger than 65, respectively. CONCLUSION: Evaluation of ALK gene status and TKI treatment are desirable even for elderly patients.

Serum CEA and CYFRA Levels in ALK-rearranged NSCLC Patients: Correlation With Distant Metastasis.

AIM: To clarify the correlation between serum levels of carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA) and metastasis and survival in anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC) patients. PATIENTS AND METHODS: CEA and CYFRA levels in 131 ALK-rearranged NSCLC patients were determined using fluorescence in situ hybridization (FISH), real time-reverse transcription polymerase chain reaction, and immunohistochemistry, using biopsy specimens, cytology specimens, and plasma specimens. Cut-off value of each marker was determined as 10 ng/ml. RESULTS: In logistic regression analysis, higher levels of both markers had a positive relationship with bone metastases, and higher levels of CYFRA was relevant to liver metastases, and multiple-organ metastases. However, these markers were not proven to be poor prognostic factors in Cox's proportional model analysis. CONCLUSION: Elevated serum CEA and CYFRA levels seem to provide useful clinical information about presence of bone and liver metastasis and multiple-organ metastases, although they were not a powerful indicator of prognosis. These two markers may suggest the extension of metastasis and would be helpful in considering treatment options.

Nrp1 is Activated by Konjac Ceramide Binding-Induced Structural Rigidification of the a1a2 Domain.

Konjac ceramide (kCer) is a plant-type ceramide composed of various long-chain bases and a-hydroxyl fatty acids. The presence of d4t,8t-sphingadienine is essential for semaphorin 3A (Sema3A)-like activity. Herein, we examined the three neuropilin 1 (Nrp1) domains (a1a2, b1b2, or c), and found that a1a2 binds to d4t,8t-kCer and possesses Sema3A-like activity. kCer binds to Nrp1 with a weak affinity of mM dissociation constant (Kd). We wondered whether bovine serum albumin could influence the ligand-receptor interaction that a1a2 has with a single high affinity binding site for kCer (Kd in nM range). In the present study we demonstrated the influence of bovine serum albumin. Thermal denaturation indicates that the a1a2 domain may include intrinsically disordered region (IDR)-like flexibility. A potential interaction site on the a1 module was explored by molecular docking, which revealed a possible Nrp1 activation mechanism, in which kCer binds to Site A close to the Sema3A-binding region of the a1a2 domain. The a1 module then accesses a2 as the IDR-like flexibility becomes ordered via kCer-induced protein rigidity of a1a2. This induces intramolecular interaction between a1 and a2 through a slight change in protein secondary structure.

Real Clinical Practice in ALK-rearranged NSCLC Patients: A Retrospective Observational Study.

BACKGROUND/AIM: To describe real clinical outcomes when using systemic therapy to treat non-small cell lung cancer (NSCLC) patients who have anaplastic lymphoma kinase (ALK) fusion gene mutation. PATIENTS AND METHODS: We performed a retrospective chart review from April 2008 to March 2019 sourced from 16 medical institutes that cover a population of three million people. RESULTS: There were 129 ALK rearranged NSCLC patients. Among them, 103 patients including 40 recurrent disease cases received ALK-tyrosine kinase inhibitors (TKI) and chemotherapy. Our treatment results were comparable to previously reported clinical trials and clinical practice studies. First-line alectinib, treatment sequence of ALK-TKI followed by another ALK-TKI, and pemetrexed-containing chemotherapy contributed to the outcome of treatment. CONCLUSION: By arrangement of treatment such as treatment sequence of ALK-TKI and chemotherapy regimen, it might be possible to obtain a treatment outcome almost equivalent to those of clinical trials even in real clinical practice.

Development of a novel class of peroxisome proliferator-activated receptor (PPAR) gamma ligands as an anticancer agent with a unique binding mode based on a non-thiazolidinedione scaffold.

We previously identified dibenzooxepine derivative 1 as a potent PPARγ ligand with a unique binding mode owing to its non-thiazolidinedione scaffold. However, while 1 showed remarkably potent MKN-45 gastric cancer cell aggregation activity, an indicator of cancer differentiation-inducing activity induced by PPARγ activation, we recognized that 1 was metabolically unstable. In the present study, we identified a metabolically soft spot, and successfully discovered 3-fluoro dibenzooxepine derivative 9 with better metabolic stability. Further optimization provided imidazo[1,2-a]pyridine derivative 17, which showed potent MKN-45 gastric cancer cell aggregation activity and excellent PK profiles compared with 9. Compound 17 exerted a growth inhibitory effect on AsPC-1/AG1 pancreatic tumor in mice. Furthermore, the decrease in the hematocrit (an indicator of localized edema, a serious adverse effect of PPARγ ligands) was tolerable even with oral administration at 200 mg/kg in healthy mice.

Pleural fluid due to papillary thyroid cancer.

We report herein a rare case of massive pleural effusion caused by papillary thyroid cancer, which was accompanied by multiple pulmonary metastasis. A 91-year-old male patient presented with shortness of breath due to massive right pleural fluid. Cytological specimens, which were obtained from pleural fluid by thoracentesis, and was consistent with that observed in surgically resected thyroid cancer 6-year previously. Immunocytochemical staining of the cells was positive for cytokeratin (CK)-7, CK-19, and positive for thyroglobulin. Massive pleural fluid due to a metastatic from papillary thyroid cancer is very rare but may develop in long-term survivors with this disease as observed in this case.

Overexpression of absent in melanoma 2 in oral squamous cell carcinoma contributes to tumor progression.

We had previously reported that in addition to p53 inactivation, overexpression of the DNA sensor protein-absent in melanoma 2 (AIM2)-contributes to tumorigenesis of oral squamous cell carcinoma (OSCC). Given that AIM2 is highly expressed in the OSCC tumors from patients with metastasis, we investigated whether AIM2 expression contributes to the progression of OSCC metastasis. In in vitro assays using OSCC cell lines, the high migration and invasion capacity of OSCC cells were dependent on the increased expression of AIM2, resulting in enhanced epithelial-mesenchymal transition (EMT), with EMT-related gene expression. Moreover, the in vivo short-term metastasis assay using orthotopic implantation into immunodeficient mice demonstrated that OSCC cells with high levels of AIM2 expression exhibited enhanced tumor growth in the tongue, resulting in decreased survival of the mice. Further, the cells overexpressing AIM2 dominantly invaded into the tumor lymphatic vessels, unlike OSCC cells with low AIM2 expression. Thus, the high expression of AIM2 in OSCC enhances progression of tumor growth.

Development of Dihydrodibenzooxepine Peroxisome Proliferator-Activated Receptor (PPAR) Gamma Ligands of a Novel Binding Mode as Anticancer Agents: Effective Mimicry of Chiral Structures by Olefinic E/ Z-Isomers.

A novel class of PPARγ ligand 1 (EC50 = 197 nM) with a dibenzoazepin scaffold was identified through high-throughput screening campaign. To avoid the synthetically troublesome chiral center of 1, its conformational analysis using the MacroModel was conducted, focusing on conformational flip of the tricyclic ring and the conformational restriction by the methyl group at the chiral center. On the basis of this analysis, scaffold hopping of dibenzoazepine into dibenzo[ b, e]oxepine by replacing the chiral structures with the corresponding olefinic E/ Z isomers was performed. Consequently, dibenzo[ b, e]oxepine scaffold 9 was developed showing extremely potent PPARγ reporter activity (EC50 = 2.4 nM, efficacy = 9.5%) as well as differentiation-inducing activity against a gastric cancer cell line MKN-45 that was more potent than any other well-known PPARγ agonists in vitro (94% at 30 nM). The X-ray crystal structure analysis of 9 complexed with PPARγ showed that it had a unique binding mode to PPARγ ligand-binding domain that differed from that of any other PPARγ agonists identified thus far.

Real Clinical Practice of Using Afatinib Therapy in NSCLC Patients with an Acquired EGFR T790M Mutation.

BACKGROUND/AIM: To describe real clinical outcomes when using afatinib therapy to treat non-small cell lung cancer patients who have an acquired EGFR T790M mutation. MATERIALS AND METHODS: A retrospective chart review was conducted from January 2013 to November 2017 sourced from 15 medical institutes that cover a population of three million people. RESULTS: There were 74 patients who met the above-mentioned criteria. Treatment outcomes with afatinib, in patients with or without tyrosine kinase inhibitor (TKI) therapy prior to afatinib, were similar to previously reported clinical trials. Stratification of patients by the presence or absence of TKI pretreatment before afatinib, and the presence or absence of an acquired T790M mutation found no statistical difference in overall survival. CONCLUSION: This population-based study found that the disadvantages of pretreatment before afatinib, and absence of an acquired T790M EGFR mutation, could be overcome by an appropriate treatment strategy in clinical practice.