Proteomic profiling of FFPE specimens: Discovery of HNRNPA2/B1 and STT3B as biomarkers for determining formalin fixation durations.

Recent advancements in proteomics technologies using formalin-fixed paraffin-embedded (FFPE) samples have significantly advanced biomarker discovery. Yet, the effects of varying sample preparation protocols on proteomic analyses remain poorly understood. We analyzed mouse liver FFPE samples that varied in fixatives, fixation duration, and storage temperature using LC/MS. We found that variations in fixation duration significantly affected the abundance of specific proteins, showing that HNRNPA2/B1 demonstrated a significant decrease in abundance in samples fixed for long periods, whereas STT3B exhibited a significant increase in abundance in samples fixed for long durations. These findings were supported by immunohistochemical analysis across liver, spleen, and lung tissues, demonstrating a significant decrease in the nuclear staining of HNRNPA2/B1 in long-duration acid formalin(AF)-fixed FFPE samples, and an increase in cytoplasmic staining of STT3B in long-duration neutral buffered formalin-fixed liver and lung tissues and granular staining in all long-duration AF-fixed FFPE tissue types. Similar trends were observed in the long-duration fixed HeLa cells. These results demonstrate that fixation duration critically affects the proteomic integrity of FFPE samples, emphasizing the urgent need for standardized fixation protocols to ensure consistent and reliable proteomic data. SIGNIFICANCE: The quality of FFPE samples is primarily influenced by the fixation and storage conditions. However, previous studies have mainly focused on their impact on nucleic acids and the extent to which different fixation conditions affect changes in proteins has not been evaluated. In addition, to our knowledge, proteomic research focusing on differences in formalin fixation conditions has not yet been conducted. Here, we analyzed FFPE samples with different formalin fixation and storage conditions using LC/MS and evaluated the impact of different fixation conditions on protein variations. Our study unequivocally established formalin fixation duration as a critical determinant of protein variation in FFPE specimens and successfully identified HNRNPA2/B1 and STT3B as potential biomarkers for predicting formalin fixation duration for the first time. The study findings open new avenues for quality assessment in biomedical research and diagnostics.

Validity study of the Japanese version of the Nijmegen Questionnaire for verifying dysfunctional breathing in Japanese asthma patients.

Background: Dysfunctional breathing (DB) is a clinical condition characterized by irregular breathing patterns presenting a sensation of dyspnea and a feeling of chest tightness. DB is a known comorbidity of asthma that is difficult to control, leading to poor quality of life, so early diagnosis and therapeutic intervention are essential to improve the clinical condition of asthma. The Nijmegen Questionnaire (NQ), developed to screen for DB and translated into various languages, is used worldwide. However, a Japanese NQ (JNQ) is unavailable, so DB has not been clinically verified in people with asthma in Japan. Objective: This study aimed to prepare a JNQ, verify its reliability and validity, and demonstrate its clinical benefits in asthma treatment. Methods: The JNQ was prepared by back-translating the NQ with the author's consent. The answers to self-administered questionnaires, including the JNQ, Asthma Control Test (ACT), Asthma Control Questionnaire (ACQ), Mini Asthma Quality of Life Questionnaire (Mini-AQLQ), and Patient Health Questionnaire 9 (PHQ-9), were obtained with the consent of 68 people with asthma (average age ± SD, 52.04 ± 12.43 years) who visited Nihon University Itabashi Hospital. The reliability of the JNQ was analyzed by the Cronbach alpha coefficient. A comparative test was conducted for each questionnaire (ACT, ACQ, Mini-AQLQ, PHQ-9), considering a JNQ score of 23 as the cutoff value. Patients with a score of 23 or more were assigned to the DB group, whereas patients with a score of less than 23 were assigned to the non-DB group. We analyzed the correlation between the JNQ and each questionnaire. Results: The JNQ showed sufficient reliability (Cronbach alpha = 0.875). Correlation analysis between the JNQ score and each questionnaire revealed negative correlations with the ACT score (r = 0.262) and Mini-AQLQ score (r = -0.453) and positive correlations with the ACQ score (r = 0.337) and PHQ-9 score (r = 0.539). All of these correlations were statistically significant. As a result of the comparative test, the DB and non-DB groups showed a significant difference in Mini-AQLQ (P = .023) and PHQ-9 (P = .003) scores. No significant difference was observed between ACT (P = .294) and ACQ (P = .177) scores. Conclusions: The JNQ validates DB in Japanese people with asthma and reflects the deterioration of asthma control, decreased quality of life, and depression. Using the JNQ, early diagnosis and therapeutic intervention (eg, breathing exercises and a psychosomatic approach) for DB in people with asthma may help suppress the severity of asthma in Japan.

Predictive Model for Occurrence of Febrile Neutropenia after Chemotherapy in Patients with Diffuse Large B-Cell Lymphoma: A Multicenter, Retrospective, Observational Study.

Febrile neutropenia (FN) is a major concern in patients undergoing chemotherapy for diffuse large B-cell lymphoma (DLBCL); however, the overall risk of FN is difficult to assess. This study aimed to develop a model for predicting the occurrence of FN in patients with DLBCL. In this multicenter, retrospective, observational analysis, a multivariate logistic regression model was used to analyze the association between FN incidence and pretreatment clinical factors. We included adult inpatients and outpatients (aged ≥ 18 years) diagnosed with DLBCL who were treated with chemotherapy. The study examined 246 patients. Considering FN occurring during the first cycle of chemotherapy as the primary outcome, a predictive model with a total score of 5 points was constructed as follows: 1 point each for a positive hepatitis panel, extranodal involvement, and a high level of soluble interleukin-2 receptor and 2 points for lymphopenia. The area under the receiver operating characteristic curve of this model was 0.844 (95% confidence interval: 0.777-0.911). Our predictive model can assess the risk of FN before patients with DLBCL start chemotherapy, leading to better outcomes.