Prognostic significance of initial tumor shrinkage in patients with stage III non-small cell lung cancer treated with durvalumab following chemoradiotherapy.

BACKGROUND: Baseline tumor size (BTS) is one of the prognostic factors of advanced non-small cell lung cancer (NSCLC) treated with immunotherapy. However, its prognostic value in patients with locally advanced NSCLC receiving durvalumab maintenance therapy remains unclear. METHODS: The present study retrospectively reviewed 136 patients with unresectable stage III NSCLC who underwent CRT and durvalumab at two institutions in Japan. The maximum diameter of the target lesion (max BTS) before CRT was measured, the best response to CRT before durvalumab was evaluated, and the impact of the response on durvalumab was explored. Progression-free survival (PFS) and overall survival (OS) were defined as the time from the day of starting durvalumab. RESULTS: Of the total cohort, 133 (97.8%) patients had at least one measurable lesion. The best response to CRT resulting in CR, PR, and SD was seen in 0 (0%), 69 (51.9%), and 64 (48.1%) patients, respectively. PFS was significantly longer in the patients with PR than in those with SD after CRT (median not reached vs. 20.0 months; HR: 0.51; P = 0.023). Moreover, the absence of a massive lesion (max BTS < 50 mm) was associated with a superior CRT response (P < 0.001). CONCLUSION: The best response to induction CRT was associated with better PFS in patients with stage III NSCLC receiving durvalumab following chemoradiotherapy. Although the absence of a massive lesion was associated with a better response to induction CRT in this cohort, this was not translated into PFS and OS benefit.

High-resolution crystal structure of peptidyl-tRNA hydrolase from Thermus thermophilus.

Peptidyl-tRNA hydrolase (Pth) cleaves the ester bond between the peptide and the tRNA of peptidyl-tRNA molecules, which are the products of defective translation, to recycle the tRNA for further rounds of protein synthesis. Pth is ubiquitous in nature, and its activity is essential for bacterial viability. Here, we have determined the crystal structure of Pth from Thermus thermophilus (TtPth) at 1.00 Å resolution. This is the first structure of a Pth from a thermophilic bacterium and the highest resolution Pth structure reported so far. The present atomic resolution data enabled the calculation of anisotropic displacement parameters for all atoms, which revealed the directionality of the fluctuations of key regions for the substrate recognition. Comparisons between TtPth and mesophilic bacterial Pths revealed that their structures are similar overall. However, the structures of the N- and C-terminal, loop-helix α4, and helix α6 regions are different. In addition, the helix α1 to strand ß4 region of TtPth is remarkably different from those of the mesophilic bacterial Pths, because this region is 9 or 10 amino acid residues shorter than those of the mesophilic bacterial Pths. This shortening seems to contribute to the thermostability of TtPth. To further understand the determinants for the thermostability of TtPth, we compared various structural factors of TtPth with those of mesophilic bacterial Pths. The data suggest that the decreases in accessible surface area and thermolabile amino acid residues, and the increases in ion pairs, hydrogen bonds, and proline residues cooperatively contribute to the thermostability of TtPth.

Molecular changes associated with the development of resistance to imatinib in an imatinib-sensitive canine neoplastic mast cell line carrying a KIT c.1523A>T mutation.

Although imatinib has therapeutic activity for certain subsets of patients with mastocytosis, it is not always curative. Here, molecular mechanisms that confer imatinib resistance to neoplastic mast cells were investigated using an imatinib-sensitive canine neoplastic mast cell line VI-MC carrying a KIT c.1523A>T activating mutation. Two imatinib-resistant sublines were established by culturing VI-MC cells in increasing concentrations of imatinib (1 µM resistant, rVI-MC1; 10 µM resistant, rVI-MC10). Both sublines had a second KIT mutation c.2443G>C. Recombinant KIT with the second mutation was insensitive to 1 µM but sensitive to 10 µM imatinib. The effect of imatinib on the phosphorylation of KIT and its downstream signalling proteins was then examined using these sublines. KIT and ERK were constitutively phosphorylated in both sublines, and their phosphorylation was suppressed by 10 µM imatinib in rVI-MC1 cells. However, KIT but not ERK phosphorylation was suppressed in rVI-MC10 cells. The phosphorylation of ERK in rVI-MC10 cells was also not diminished by the Src family kinase (SFK) inhibitor dasatinib. This second mutation in KIT may play an important role in imatinib resistance in neoplastic mast cells. Furthermore, KIT/SFK-independent activation of ERK would be involved in imatinib resistance when the neoplastic cells are exposed to higher concentrations of imatinib.

Anoikis-related subtype and prognosis analyses based on bioinformatics, and an expression verification of ANGPTL4 based on experiments of lung adenocarcinoma.

Background: Lung adenocarcinoma (LUAD) is one of the most common malignant tumors with high mortality. Anoikis resistance is an important mechanism of tumor cell proliferation and migration. Our research is devoted to exploring the role of anoikis in the diagnosis, classification, and prognosis of LUAD. Methods: We downloaded the expression profile, mutation, and clinical data of LUAD from The Cancer Genome Atlas (TCGA) database. The "ConsensusClusterPlus" package was then used for the cluster analysis, and least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analyses were used to establish the prognostic model. We verified the reliability of the model using a Gene Expression Omnibus (GEO) data set. A gene set variation analysis (GSVA) was conducted to investigate the functional enrichment differences in the different clusters and risk groups. The CIBERSORT algorithm and a single-sample gene set enrichment analysis (ssGSEA) were used to analyze immune cell infiltration. The tumor mutation burden (TMB) and Tumor Immune Dysfunction and Exclusion (TIDE) scores were used to evaluate the patients' sensitivity to immunotherapy. Immunohistochemical staining of tissue microarrays was used to verify the correlation between ANGPTL4 expression and the clinicopathological characteristics and prognosis of LUAD patients. Results: First, we screened 135 differentially expressed anoikis-related genes (ARGs) and 23 prognosis-related ARGs from TCGA-LUAD data set. Next, 494 LUAD samples were allocated to cluster A and cluster B based on the 23 prognosis-related ARGs. The Kaplan-Meier (K-M) analysis showed the overall survival (OS) of cluster B was better than that of cluster A. The clinicopathological characteristics and functional enrichment analyses revealed significant differences between clusters A and B. The tumor microenvironment (TME) analysis showed that cluster B had more immune cell infiltration and a higher TME score than cluster A. Subsequently, a LASSO Cox regression model of LUAD was constructed with ten ARGs. The K-M analysis showed that the low-risk patients had longer OS than the high-risk patients. The receiver operating characteristic curve, nomogram, and GEO data set verification results showed that the model had high accuracy and reliability. The level of immune cell infiltration and TME score were higher in the low-risk group than the high-risk group. The high-risk group had stronger sensitivity to immune checkpoint block therapy and weaker sensitivity to chemotherapy drugs than the low-risk group. ANGPTL4 expression was correlated with stage, tumor differentiation, tumor size, lymph node metastasis, and OS. Conclusions: We discovered novel molecular subtypes and constructed a novel prognostic model of LUAD. Our findings provide important insights into subtype classification and the accurate survival prediction of LUAD. We also identified ANGPTL4 as a prognostic indicator of LUAD.

Brief Report: Clinical Outcomes by Infusion Timing of Immune Checkpoint Inhibitors in Patients With Locally Advanced NSCLC.

Introduction: Previous studies reported an association between immune checkpoint inhibitor infusion timing and the treatment effect in metastatic NSCLC. The present study assessed the association between durvalumab infusion timing and survival outcomes in patients with locally advanced NSCLC. Methods: Patients receiving durvalumab after chemoradiotherapy for locally advanced NSCLC at a single institution were retrospectively analyzed, and the association of the proportion of durvalumab infusions greater than or equal to 20% versus less than 20% after 3 PM with progression-free survival (PFS) and overall survival was assessed. Results: A total of 82 patients were included, with a median age of 69 years (interquartile range, 62-74 years); of these, 67 patients (82%) were of male sex, and 78 patients (95%) had a history of smoking. The median number of durvalumab infusions per patient was 16 (interquartile range, 8-24). Patients with at least 20% of their durvalumab infusions after 3 PM (n = 12/82, 15%) had a significantly shorter PFS than those who did not (median: 7.4 mo versus not available [NA]; hazard ratio [HR], 2.43; 95% confidence interval [CI]: 1.11-5.34, p = 0.027), whereas overall survival was shorter among the former compared with the latter group (median: 22.4 versus NA; HR, 1.80; 95% CI: 0.73-4.42, p = 0.20). In addition, both backward stepwise multivariable analysis and propensity score-matching analysis revealed that receiving at least 20% of durvalumab infusions after 3 PM was significantly associated with worse PFS (HR, 2.54; 95% CI: 1.03-5.67, p = 0.047; and HR, 4.64; 95% CI: 1.95-11.04; p < 0.001, respectively). Conclusions: The time of day of durvalumab infusions may impact survival outcomes in patients with locally advanced NSCLC.

Successful Treatment of ALK-Positive Large-Cell Neuroendocrine Carcinoma of the Lung With Sequential ALK Inhibitors: A Case Report.

ALK-positive large-cell neuroendocrine carcinoma (LCNEC) is an exceptionally rare form of lung cancer. The efficacy of ALK inhibitors in treating ALK-positive LCNEC remains unclear. Here, we report a case of ALK-positive LCNEC of the lung, which revealed a sustained clinical benefit (24+ mo of overall survival) after treatment with sequential ALK inhibitors and local therapies. This remarkable improvement in survival underscores the importance of testing metastatic LCNEC for biomarkers, such as ALK rearrangement, using immunohistochemistry or next-generation sequencing, especially in younger patients.

Travel Time and Distance and Participation in Precision Oncology Trials at the National Cancer Center Hospital.

Importance: Genotype-matched trials, which are becoming increasingly important in the precision oncology era, require referrals from institutions providing comprehensive genomic profiling (CGP) testing to those conducting these trials, and the travel burden for trial participation is significant. However, it remains unknown whether travel time or distance are associated with genotype-matched trial participation. Objective: To assess whether travel time or distance are associated with disparities in genotype-matched trial participation following CGP testing. Design, Setting, and Participants: This retrospective cohort study from June 2020 to June 2022 included patients with advanced or metastatic solid tumors referred to the National Cancer Center Hospital for participation in genotype-matched trials following CGP testing and discussion by molecular tumor boards. Data were analyzed from June to October 2022. Exposures: Travel time and distance. Main Outcomes and Measures: The primary and secondary outcomes were enrollment in genotype-matched trials and all-cancer clinical trials, respectively. Results: Of 1127 patients (mean [range] age, 62 [16-85] years; 584 women [52%]; all residents of Japan), 127 (11%) and 241 (21%) were enrolled in genotype-matched trials and all-cancer clinical trials, respectively. The overall median (IQR) travel distance and time were 38 (21-107) km and 55 (35-110) minutes, respectively. On multivariable regression with 23 covariates, travel distance (≥100 km vs <100 km) was not associated with the likelihood of genotype-matched trial participation (26 of 310 patients [8%] vs 101 of 807 patients [12%]; odds ratio [OR], 0.64; 95% CI, 0.40-1.02), whereas in patients with travel time of 120 minutes or more, the likelihood of genotype-matched trial participation was significantly lower than those with travel time less than 120 minutes (19 of 276 patients [7%] vs 108 of 851 patients [13%]; OR, 0.51; 95% CI, 0.29-0.84). The likelihood of genotype-matched trial participation decreased as travel time increased from less than 40 (38 of 283 patients [13%]) to 40 to 120 (70 of 568 patients [12%]) and 120 or more (19 of 276 patients [7%]) minutes (OR, 0.74; 95% CI, 0.48-1.17; OR, 0.41; 95% CI, 0.22-0.74, respectively). Neither travel time nor distance were associated with the likelihood of all-cancer clinical trial participation. Conclusions and Relevance: In this cohort study of patients undergoing CGP testing, an increased travel time was associated with a decreased likelihood of genotype-matched trial participation. This warrants further research on interventions, such as decentralization of clinical trials to mitigate travel burden.

Efficacy of first-line immune checkpoint inhibitors in patients with advanced NSCLC with KRAS, MET, FGFR, RET, BRAF, and HER2 alterations.

BACKGROUND: In patients with non-small cell lung cancer (NSCLC) harboring driver alterations, the efficacy of immune checkpoint inhibitors (ICIs) remains uncertain. Our study aimed to examine the first-line ICI efficacy in patients with NSCLC harboring KRAS, MET, FGFR, RET, BRAF, and HER2 alterations in a real-world setting. METHODS: This single-center, retrospective cohort study included patients with advanced NSCLC harboring KRAS, MET, FGFR, RET, BRAF, HER2 alterations or driver-negative, and were treated with first-line ICI therapy. Best overall response, progression-free survival (PFS), and overall survival (OS) were evaluated. RESULTS: Seventy-eight patients with NSCLC were included (median age, 72 years): 67% were men, 15% were never-smokers, and 83% had adenocarcinoma. The driver alterations involved KRAS (n = 21), MET (n = 6), FGFR (n = 3), RET (n = 2), BRAF (n = 2), HER2 (n = 1), and driver-negative (n = 43). The partial responses for KRAS, MET, FGFR, RET, BRAF, HER2, and driver-negative were 57%, 50%, 100%, 50%, 100%, 0%, and 47%, respectively. The median PFS (months) was 16.2 (95% confidence interval [CI]: 6.3- not reached [NR]) for KRAS, 2.8 (95% CI: 2.7-NR) for MET, 11.7 (95% CI: 5.9-NR) for other alterations (FGFR, RET, BRAF, and HER2), and 10.0 (95% CI: 3.7-14.3) for driver-negative, respectively. The median OS (months) was 31.3 (95% CI: 9.0-NR) for KRAS, not reached for MET, 23.5 (95% CI: 18.3-NR) for other alterations, and 21.1 (95% CI: 15.2-NR) for driver-negative, respectively. CONCLUSIONS: The benefit of the first-line ICI was similar in advanced NSCLC regardless of the driver alterations, except for MET alterations.

Association between the baseline tumor size and outcomes of patients with non-small cell lung cancer treated with first-line immune checkpoint inhibitor monotherapy or in combination with chemotherapy.

Background: The baseline tumor size (BTS) is a prognostic factor for patients with non-small cell lung cancer (NSCLC) who received immune checkpoint inhibitor monotherapy (ICI-mono). However, this relationship is not yet known in patients treated with ICI in combination with chemotherapy (ICI-chemo). Methods: This single-center retrospective study evaluated 159 patients with advanced NSCLC who received first-line ICI-mono or ICI-chemo from January 2016 to April 2021. Their BTS values were estimated using the maximum BTS (max BTS) (maximum target lesions' longest diameter) and total BTS (sum of target lesions' longest diameters) in a radiological assessment according to the Response Evaluation Criteria for Solid Tumors. Results: Based on a multivariable analysis, the large max BTS group had worse progression-free survival (PFS) in patients treated with ICI-mono (P=0.009), but it was not associated with worse PFS in patients treated with ICI-chemo (P=0.132). The group treated with ICI-mono had worse PFS compared to the group treated with ICI-chemo in patients with max BTS ≥50 mm (P=0.004), and the group treated with ICI-mono was not associated with worse PFS compared to the group treated with ICI-chemo in patients with max BTS <50 mm (P=0.107). Conclusions: While a large max BTS was identified as a prognostic factor for worse PFS in patients treated with ICI-mono, it was not identified as such in patients treated with ICI-chemo. The max BTS may have different predicting efficacy for patients with NSCLC treated with ICI-mono and ICI-chemo.

Aspergillus Sternomyelitis Developed from Chronic Pulmonary Aspergillosis as a Late Complication to Lobectomy for Lung Cancer.

Progressive fibrobullous changes in the residual lobes are sometimes observed after lobectomy. Aspergillus osteomyelitis is an uncommon infection that rarely occurs sternally. A 70-year-old man who had undergone lobectomy 12 years earlier was admitted to our hospital for chest pain. He was diagnosed with Aspergillus sternomyelitis based on sternal bone culture after an ultrasound-guided percutaneous needle biopsy. The fibrosis and right residual lung apex volume loss had gradually progressed over 12 years, and therefore, chronic pulmonary aspergillosis (CPA) with direct invasion sternal from the CPA was considered. Aspergillus sternomyelitis can develop from CPA as a late complication of lobectomy.