Response to mRNA SARS-CoV-2 vaccination evaluated by B-cell receptor repertoire after tixagevimab/cilgavimab administration.

The use of anti-SARS-CoV-2 antibody products like tixagevimab/cilgavimab represents an important strategy to protect immunocompromised patients with haematological malignancies from COVID-19. Although patients who receive these agents should still be vaccinated, the use of tixagevimab/cilgavimab can mask the production of anti-spike antibody after vaccination, making it hard to assess vaccine response. We have newly established a quantification method to assess the response to SARS-CoV-2 vaccination at the mRNA level using B-cell receptor (BCR) repertoire assay and the Coronavirus Antibody Database (CoV-AbDab). Repeated blood samples before and after vaccination were analysed for the BCR repertoire, and BCR sequences were searched in the database. We analysed the number and percentage frequency of matched sequences. We found that the number of matched sequences increased 2 weeks after the first vaccination and quickly decreased. Meanwhile, the number of matched sequences more rapidly increased after the second vaccination. These results show that the postvaccine immune response can be assessed at the mRNA level by analysing the fluctuation in matching sequences. Finally, BCR repertoire analysis with CoV-AbDab clearly demonstrated the response to mRNA SARS-CoV-2 vaccination even after tixagevimab/cilgavimab administration in haematological malignancy patients who underwent allogeneic haematopoietic stem cell transplantation.

The Usefulness of Total Tumor Volume as a Prognostic Factor and in Selecting the Optimal Treatment Strategy of Chemotherapeutic Intervention in Patients with Colorectal Liver Metastases.

BACKGROUND: Few reports have discussed the association between total tumor volume (TTV) and prognosis in patients with colorectal liver metastases (CRLM). The present study aimed to evaluate the usefulness of TTV for predicting recurrence-free survival and overall survival (OS) in patients receiving initial hepatic resection or chemotherapy, and to investigate the value of TTV as an indicator for optimal treatment selection for patients with CRLM. PATIENTS AND METHODS: This retrospective cohort study included patients with CRLM who underwent hepatic resection (n = 93) or chemotherapy (n = 78) at the Kobe University Hospital. TTV was measured using 3D construction software and computed tomography images. RESULTS: A TTV of 100 cm3 has been previously reported as a significant cut-off value for predicting OS of CRLM patients receiving initial hepatic resection. For patients receiving hepatic resection, the OS for those with a TTV ≥ 100 cm3 was significantly reduced compared with those with a TTV < 100 cm3. For patients receiving initial chemotherapy, there were no significant differences between the groups divided according to TTV cut-offs. Regarding OS of patients with TTV ≥ 100 cm3, there was no significant difference between hepatic resection and chemotherapy (p = 0.160). CONCLUSIONS: TTV can be a predictive factor of OS for hepatic resection, unlike for initial chemotherapy treatment. The lack of significant difference in OS for CRLM patients with TTV ≥ 100 cm3, regardless of initial treatment, suggests that chemotherapeutic intervention preceding hepatic resection may be indicated for such patients.

Comparable efficacy and safety of COVID-19 vaccines for patients receiving tegafur-uracil as postoperative adjuvant chemotherapy.

PURPOSE: Many effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been developed, but a weaker response in individuals undergoing anticancer treatment has been reported. This study evaluates the immunogenic status and safety of SARS-CoV-2 vaccines for patients with non-small-cell lung cancer (NSCLC), receiving tegafur-uracil (UFT) as postoperative adjuvant chemotherapy. METHODS: The subjects of this prospective study were 40 patients who underwent surgery for NSCLC and received SARS-CoV-2 vaccines postoperatively. We compared the antibody titers of SARS-CoV-2 vaccines and the adverse events between patients who received adjuvant UFT and patients who did not. RESULTS: The mean anti-S1 IgG titers were not significantly different between the UFT and without-UFT groups (mean optimal density, 0.194 vs. 0.205; P = 0.76). Multivariate analysis identified the period after the second vaccination as an independent predictor of anti-S1 IgG titer (P = 0.049), but not the UFT status (with or without-UFT treatment; P = 0.47). The prevalence of adverse events did not differ significantly between the groups, and no severe adverse events occurred. CONCLUSIONS: The efficacy and safety of the SARS-CoV-2 vaccines for NSCLC patients who received postoperative adjuvant UFT chemotherapy were comparable to those for NSCLC patients who did not receive postoperative adjuvant UFT chemotherapy. CLINICAL TRIAL REGISTRATION: This study was registered with the University Hospital Medical Information Network (UMIN) in Japan (UMIN000047380).

Safety and immunogenicity of the COVID-19 vaccine BNT162b2 in patients undergoing chemotherapy for solid cancer.

BACKGROUND: Although COVID-19 severity in cancer patients is high, the safety and immunogenicity of the BNT162b2 mRNA COVID-19 vaccine in patients undergoing chemotherapy for solid cancers in Japan have not been reported. METHODS: We investigated the safety and immunogenicity of BNT162b2 in 41 patients undergoing chemotherapy for solid cancers and in healthy volunteers who received 2 doses of BNT162b2. We evaluated serum IgG antibody titers for S1 protein by ELISA at pre-vaccination, prior to the second dose and 14 days after the second vaccination in 24 cancer patients undergoing cytotoxic chemotherapy (CC group), 17 cancer patients undergoing immune checkpoint inhibitor therapy (ICI group) and 12 age-matched healthy volunteers (HV group). Additionally, inflammatory cytokine levels were compared between the HV and ICI groups at pre and the next day of each vaccination. RESULTS: Anti-S1 antibody levels were significantly lower in the ICI and CC groups than in the HV group after the second dose (median optimal density: 0.241 [0.063-1.205] and 0.161 [0.07-0.857] vs 0.644 [0.259-1.498], p = 0.0024 and p < 0.0001, respectively). Adverse effect profile did not differ among the three groups, and no serious adverse event occurred. There were no differences in vaccine-induced inflammatory cytokines between the HV and ICI groups. CONCLUSION: Although there were no significant differences in adverse events in three groups, antibody titers were significantly lower in the ICI and CC groups than in the HV group. Further protection strategies should be considered in cancer patients undergoing CC or ICI.

Expression of programmed death-1 in sentinel lymph nodes of breast cancer.

BACKGROUND AND OBJECTIVES: To explore whether lymphocytes in sentinel lymph nodes (SLNs) are highly exposed to tumor neoantigens and thus express high level of programmed death 1 (PD-1), we examined PD-1 expression in SLNs and non-sentinel regional lymph nodes (non-SLNs) in breast cancer. METHODS: We performed PD-1 immunohistochemistry in two cohorts: 40 metastasis-negative SLNs including 10 patients for each subtype (luminal A-like, luminal B-like, HER2, and triple negative breast cancer [TNBC]); and 25 pairs of metastasis-positive SLNs and non-SLNs (10 luminal A-like, 10 luminal B-like, and 5 TNBC). RESULTS: Among 40 metastasis-negative SLNs, 34 and 6 samples were PD-1 intensity grade 1 (low) and 2 (high), respectively. PD-1 intensity correlated with PD-1-positive lymphocyte numbers (P = 0.005); TNBC had the highest PD-1 lymphocyte numbers among all subtypes. The median PD-1-positive lymphocyte number was higher in SLNs than non-SLNs. In most cases, more lymphocytes in SLNs expressed PD-1 than those in non-SLNs (P < 0.0001). CONCLUSIONS: TNBC had the greatest PD-1 expression among all subtypes, and metastasis-positive SLNs had more PD-1-positive lymphocytes than downstream non-SLNs. These data suggested that lymphocytes in SLNs are activated following exposure to tumor neoantigens and thus tumor specific, and could be utilized as a biomarker platform.

[Effect of Natural Killer Cell Infiltration on the Growth of Breast Cancer Patient-Derived Tumor Xenografts].

Natural killer (NK) cells, a component of the innate immunity, play important roles in tumor suppression. In this study, three human breast cancer patient-derived tumor xenografts (PDXs), established by the transplantation of surgical specimens, were passaged in immunodeficient NOD/SCID mice or NSG mice, that further lacks NK cell activity. The intensity of the relative growth suppression between NOD/SCID and NSG mice was clearly different depending on the PDX lines, and it was associated with the intensities of the CD49b-positive NK cell infiltration in the PDX tumor tissues. However, no obvious association was observed between the mRNA expression levels of the NK cell ligands in the PDX tumor cells and the intensity of NK cell infiltration into the PDX tumors. These results suggest that the suppressive effect of NK cells on the growth of breast cancer PDX is highly variable depending on the PDX lines. Further studies are needed to elucidate the molecular mechanism of NK cell infiltration in PDX tumors.

Protocol for a phase II study to evaluate the efficacy and safety of nivolumab as a postoperative adjuvant therapy for patients with esophageal cancer treated with preoperative docetaxel, cisplatin plus 5-fluorouracil treatment (PENTAGON trial).

BACKGROUND: In Japan, preoperative adjuvant chemotherapy followed by surgical resection is the standard treatment for patients with locally advanced esophageal squamous cell carcinoma. However, the risk of recurrence after surgical resection remains high. Although a randomized controlled trial evaluating the efficacy of nivolumab, a fully human monoclonal anti-programmed death 1 antibody, as postoperative adjuvant therapy after neoadjuvant chemoradiotherapy and surgery established its superior efficacy as adjuvant therapy, the efficacy for patients who received preoperative adjuvant chemotherapy has not been demonstrated. This study aims to elucidate the efficacy and safety of nivolumab as postoperative adjuvant therapy for patients with esophageal squamous cell carcinoma after preoperative adjuvant chemotherapy with docetaxel and cisplatin plus 5-fluorouracil followed by surgical resection. METHODS: This study is a multi-institutional, single-arm, Phase II trial. We plan to recruit 130 esophageal squamous cell carcinoma patients, who have undergone preoperative adjuvant chemotherapy with docetaxel and cisplatin plus 5-fluorouracil followed by surgical resection. If the patient did not have a pathological complete response, nivolumab is started as a postoperative adjuvant therapy within 4-16 weeks after surgery. The nivolumab dose is 480 mg/day every four weeks. Nivolumab is administered for up to 12 months. The primary endpoint is disease-free survival; the secondary endpoints are overall survival, distant metastasis-free survival, and incidence of adverse events. DISCUSSION: To our knowledge this study is the first trial establishing the efficacy of nivolumab as postoperative adjuvant therapy for patients with esophageal squamous cell carcinoma after preoperative adjuvant chemotherapy with docetaxel and cisplatin plus 5-fluorouracil followed by surgical resection. In Japan, preoperative adjuvant chemotherapy followed by surgery is a well-established standard treatment for resectable, locally advanced esophageal squamous cell carcinoma. Therefore, developing an effective postoperative adjuvant therapy has been essential for improving oncological outcomes.

Mechanisms of acquired resistance to insulin-like growth factor 1 receptor inhibitor in MCF-7 breast cancer cell line.

The purpose of this study was to clarify the mechanism of acquired resistance to the insulin-like growth factor-1 receptor (IGF-1R) tyrosine kinase inhibitor NVP-AEW541. We developed an acquired resistant model by continuously exposing MCF-7 breast cancer cells to NVP-AEW541 (MCF-7-NR). MCF-7 and MCF-7-NR were comparatively analyzed for cell signaling and cell growth. While phosphorylation of Akt was completely inhibited by 3 µM NVP-AEW541 in both MCF-7 and MCF-7-NR, phosphorylation of S6K remained high only in MCF-7-NR, suggesting a disconnection between Akt and S6K in MCF-7-NR. Consistently, the mTOR inhibitor everolimus inhibited phosphorylation of S6K and cell growth equally in both lines. Screening of both lines for phosphorylation of 42 receptor tyrosine kinases with and without NVP-AEW541 showed that Tyro3 phosphorylation remained high only in MCF-7-NR. Protein expression of Tyro3 was found to be higher in MCF-7-NR than in MCF-7. Gene silencing of Tyro3 using siRNA resulted in reduced cell growth and cyclin D1 expression in both lines. While Tyro3 expression was inhibited by NVP-AEW541 and everolimus in MCF-7, it was reduced only by everolimus in MCF-7-NR. These findings suggested that cyclin D1 expression was regulated in a S6K/Tyro3-dependent manner in both MCF-7 and MCF-7-NR, and that the disconnection between IGF-1R/Akt and S6K may enable MCF-7-NR to keep cyclin D1 high in the presence of NVP-AEW541. In summary, acquired resistance to NVP-AEW541 appears to result from IGF-1R/Akt-independent activation of S6K and expression of Tyro3 and cyclin D1.

Excessive MET signaling causes acquired resistance and addiction to MET inhibitors in the MKN45 gastric cancer cell line.

The clinical efficacy of MET tyrosine kinase inhibitors (MET-TKIs) is hindered by the emergence of acquired resistance, presenting an obstacle to drug discovery. To clarify the mechanisms underlying acquired resistance to MET-TKIs, we established resistance models by continuous exposure of the MET-amplified gastric cancer cell line MKN45 to MET-TKIs, PHA665752 (MKN45-PR) and GSK1363089 (MKN45-GR). Baseline expression and phosphorylation of MET were elevated in MKN45-PR and MKN45-GR compared to MKN45 cells, and higher concentrations of MET-TKIs were required to inhibit MET phosphorylation compared to parental cells. Alterations in MET previously associated with resistance to MET-TKIs were observed in resistant cells, including elevated MET copy number, observed in both resistant lines compared to MKN45 cells, and the Y1230H mutation, detected in MKN45-PR cells. Notably, the growth of resistant lines was lower in the absence of MET-TKIs, suggesting "addiction" to inhibitors. While MKN45-PR cells exhibited a higher S-phase fraction in the absence of PHA665752, bromodeoxyuridine (BrdU) uptake was identical. Baseline phosphorylation of ATR, Chk1 and p53 and p21(waf1/Cip1) expression was higher in MKN45-PR compared to MKN45 cells, and levels were reduced to those observed in untreated MKN45 cells following PHA665752 treatment. Furthermore, targeted knockdown of MET enhanced the growth of MKN45-PR cells. These findings suggest that alterations in MET leading to acquired MET-TKI resistance, may cause excessive MET signaling, subsequent replication stress and DNA damage response, and intra-S-phase arrest in the absence of MET-TKIs. Thus, partial MET inhibition is necessary for resistant cells to proliferate, a phenomenon we refer to as MET-TKI "addiction".

Prediction of glomerular filtration rate in cancer patients by an equation for Japanese estimated glomerular filtration rate.

BACKGROUND: Assessment of renal function is important for safe cancer chemotherapy, and eligibility criteria for clinical trials often include creatinine clearance. However, creatinine clearance overestimates glomerular filtration rate, and various new formulae have been proposed to estimate glomerular filtration rate. Because these were developed mostly in patients with chronic kidney disease, we evaluated their validity in cancer patients without kidney disease. METHODS: Glomerular filtration rate was measured by inulin clearance in 45 Japanese cancer patients, and compared with creatinine clearance measured by 24-h urine collection as well as that estimated by the Cockcroft-Gault formula, Japanese estimated glomerular filtration rate developed in chronic kidney disease patients, the Modification of Diet in Renal Disease study equation and the Chronic Kidney Disease Epidemiology Collaboration equation. The Modification of Diet in Renal Disease study and Chronic Kidney Disease Epidemiology Collaboration equations were adjusted for the Japanese population by multiplying by 0.808 and 0.813, respectively. RESULTS: The mean inulin clearance was 79.2 ± 18.7 ml/min/1.73 m(2). Bias values to estimate glomerular filtration rate for Japanese estimated glomerular filtration rate, the Cockcroft-Gault formula, creatinine clearance measured by 24-h urine collection, the 0.808 × Modification of Diet in Renal Disease study equation and the 0.813 × Chronic Kidney Disease Epidemiology Collaboration equation were 0.94, 9.75, 29.67, 5.26 and -0.92 ml/min/1.73 m(2), respectively. Precision (root-mean square error) was 14.7, 22.4, 39.8, 16.0 and 14.1 ml/min, respectively. Of the scatter plots of inulin clearance versus each estimation formula, the Japanese estimated glomerular filtration rate correlated most accurately with actual measured inulin clearance. CONCLUSION: The Japanese estimated glomerular filtration rate and the 0.813 × Chronic Kidney Disease Epidemiology Collaboration equation estimated glomerular filtration rate with lower bias and higher precision than the other formulae. We therefore propose Japanese estimated glomerular filtration rate for the estimation of glomerular filtration rate in Japanese cancer patients.

Combined Hypophysitis and Type 1 Diabetes Mellitus Related to Immune Checkpoint Inhibitors.

Context: The occurrence of multiple endocrinopathies due to immune checkpoint inhibitors (ICIs) is a relatively common adverse event. However, the occurrence of a combination of hypophysitis and type 1 diabetes mellitus (T1DM) is extremely rare, and its clinical features are unclear. Objective: We comparatively analyzed the clinical features of this combination and each individual ICI-induced endocrinopathy. Methods: We reported 3 cases that we encountered and reviewed previously reported cases of patients with combined hypophysitis and T1DM due to ICIs. Results: Anti-programmed cell death-1 (anti-PD-1) antibodies were prescribed to all 3 cases. The duration from ICI initiation to the onset of endocrine disease was 12 to 48 weeks. Several human leukocyte antigen (HLA) haplotypes that have disease susceptibility to hypophysitis were detected in all 3 patients. With the 17 previously reported cases, combined endocrinopathies were more common in men (85%). The onset age was in the 60s for both combined and single endocrinopathies. Anti-PD-1 antibodies were used in most of the cases (90%). The time from ICI initiation to the onset of endocrinopathies was 24 (8-76) weeks for hypophysitis and 32 (8-76) weeks for T1DM in patients with combined endocrinopathies, which was not significantly different from that for each single endocrinopathy. Conclusion: We presented 3 cases of patients with combined endocrinopathies of hypophysitis and T1DM that may have been caused by anti-PD-1 antibodies. There was no difference in the time from ICI initiation to the onset of endocrinopathies between combined and single endocrinopathies. Further case accumulation and pathogenic investigations are required.

Preclinical evaluation of the efficacy of an antibody to human SIRPα for cancer immunotherapy in humanized mouse models.

Tumor-associated macrophages (TAMs) are abundant in the tumor microenvironment and are considered potential targets for cancer immunotherapy. To examine the antitumor effects of agents targeting human TAMs in vivo, we here established preclinical tumor xenograft models based on immunodeficient mice that express multiple human cytokines and have been reconstituted with a human immune system by transplantation of human CD34+ hematopoietic stem and progenitor cells (HIS-MITRG mice). HIS-MITRG mice supported the growth of both human cell line (Raji)- and patient-derived B cell lymphoma as well as the infiltration of human macrophages into their tumors. We examined the potential antitumor action of an antibody to human SIRPα (SE12C3) that inhibits the interaction of CD47 on tumor cells with SIRPα on human macrophages and thereby promotes Fcγ receptor-mediated phagocytosis of the former cells by the latter. Treatment with the combination of rituximab (antibody to human CD20) and SE12C3 inhibited Raji tumor growth in HIS-MITRG mice to a markedly greater extent than did rituximab monotherapy. This enhanced antitumor effect was dependent on human macrophages and attributable to enhanced rituximab-dependent phagocytosis of lymphoma cells by human macrophages. Treatment with rituximab and SE12C3 also induced reprogramming of human TAMs toward a proinflammatory phenotype. Furthermore, the combination treatment essentially prevented the growth of patient-derived diffuse large B cell lymphoma in HIS-MITRG mice. Our findings thus support the study of HIS-MITRG mice as a model for the preclinical evaluation in vivo of potential therapeutics, such as antibodies to human SIRPα, that target human TAMs.

Foretinib (GSK1363089), a multi-kinase inhibitor of MET and VEGFRs, inhibits growth of gastric cancer cell lines by blocking inter-receptor tyrosine kinase networks.

To explore the mechanism of action of foretinib (GSK1363089), an oral multi-kinase inhibitor known to target MET, RON, AXL, and vascular endothelial growth factor receptors (VEGFRs), in gastric cancer, we evaluated the effects of the agent on cell growth and cell signaling in the following panel of gastric cancer cell lines: KATO-III, MKN-1, MKN-7, MKN-45, and MKN-74. Of these, only MKN-45 and KATO-III, which harbor MET and fibroblast growth factor receptor 2 (FGFR2) amplification, respectively, were highly sensitive to foretinib. In MKN-45, 1 µM of foretinib or PHA665752, another MET kinase inhibitor, inhibited phosphorylation of MET and downstream signaling molecules as expected. In KATO-III, however, PHA665752 inhibited phosphorylation of MET independently of downstream molecules. Further, 1 µM of foretinib or PD173074, a selective FGFR kinase inhibitor, inhibited phosphorylation of FGFR2 and downstream molecules, suggesting that foretinib targets FGFR2 in KATO-III. We confirmed this novel activity of foretinib against FGFR2 in OCUM-2M, another FGFR2-amplified gastric cancer cell line. Using a phospho-receptor tyrosine kinase array, we found that foretinib inhibits phosphorylation of epidermal growth factor receptor (EGFR), HER3 and FGFR3 via MET inhibition in MKN-45, and EGFR, HER3 and MET via FGFR2 inhibition in KATO-III. Knockdown of HER3 and FGFR3 in MKN-45 with siRNA resulted in the partial inhibition of cell signaling and cell growth. In conclusion, foretinib appears effective against gastric cancer cells harboring not only MET but also FGFR2 amplification, and exerts its inhibitory effects by blocking inter-RTK signaling networks with MET or FGFR2 at their core.

Expression of the novel NUP98/PSIP1 fusion transcripts in myelodysplastic syndrome with t(9;11)(p22;p15).

OBJECTIVES: The t(9;11)(p22;p15) is a very rare but recurrent translocation in acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) blast crisis. The translocation results in a fusion gene between NUP98 at 11p15 and PSIP1 encoding two transcriptional coactivators, p52 and p75, at 9p22. Here, we describe the first case of myelodysplastic syndrome (MDS) with t(9;11)(p22;p15). PATIENT: A 64-yr-old woman presented pancytopenia, trilineage dysplasia, and 9.2% blasts in the bone marrow, indicating the diagnosis of MDS. RESULTS: G-banding and spectral karyotyping showed 46,XX,t(9;11)(p22;p15)[20]. Reverse transcription-polymerase chain reaction (RT-PCR) and nucleotide sequencing detected four types of NUP98/PSIP1-p52 and two types of NUP98/PSIP1-p75 fusion transcripts. Essentially, the NUP98 exon 12 or exon 11 by alternative splicing was fused in-frame with the PSIP1 exon 8. Real-time quantitative (RQ) PCR for NUP98/PSIP1/GAPDH demonstrated a 4-log decrease after cord blood transplantation and a 2-log increase at relapse. CONCLUSIONS: The fusion genes combining NUP98 exon 11/12 with PSIP1 exon 8, which have never been detected in other AML/CML cases, may be implicated in the pathogenesis of MDS. Furthermore, RQ-PCR for NUP98/PSIP1 could be useful to monitor minimal residual disease.

Transition of the PD-1 occupancy of nivolumab on T cells after discontinuation and response of nivolumab re-challenge.

Although nivolumab is administered every two or four weeks, high programmed cell death-1 (PD-1) binding of nivolumab on T cells lasting for several months has been reported. A relationship between the PD-1 occupancy rate on T-cells and the efficacy of nivolumab is not yet fully understood. The present study used flow cytometric analyses to determine the time-dependence of PD-1 occupancy in five patients who discontinued nivolumab. The relationship between PD-1 occupancy at relapse and the efficacy of re-challenge was also studied. Occupancies after discontinuation were measured at a total of 32 points. The data indicated that it took 32.4 and 48.9 weeks to decrease occupancy by 50 and 70%, respectively. Subsequently, two patients had recurrence and were re-challenged with nivolumab. At that time, one patient had 70.8% occupancy while the other had 6.6%. Treatment was effective only for the patient with lower occupancy. Overall, the present study suggests that re-challenge with nivolumab may be efficacious in patients with low occupancy at recurrence.

Inhaled corticosteroids do not affect the antibody titer against the SARS-CoV-2 spike protein in BNT162b2 mRNA vaccinated patients.

OBJECTIVES: Oral corticosteroids reduce the antibody titer of the BNT162b2 mRNA vaccine against SARS-CoV-2. To date, the effect of inhaled corticosteroids on antibody titers is unknown. STUDY DESIGN: The design of this study is retrospective study. METHODS: We analyzed the relationship between the clinical features and total antibody titers against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein in 320 subjects who had never been infected with Coronavirus disease 2019 (COVID-19) and were vaccinated the second time with the BNT162b2 mRNA vaccine between October 1 to December 28, 2021. RESULTS: Of the 320 subjects, 205 were treated with inhaled corticosteroids. The median antibody titer of patients treated with inhaled corticosteroids was 572 U/mL, which was significantly higher than that of patients treated without inhaled corticosteroids (454U/mL, P = 0.00258). The median antibody titers of smokers, men, and patients aged 65 years and over, were 315.5 U/mL, 385 U/mL, and 425.5 U/mL, respectively. These results are significantly lower than those of patients who never smoked, women, and patients aged less than 64 years (582 U/mL [P < 0.0001], 682.5 U/mL [P < 0.0001], and 717 U/mL [P < 0.0001], respectively). The multivariate analysis revealed that females and age were independent antibody titer-reducing factors (P = 0.0001 and P < 0.0001, respectively). CONCLUSIONS: The use of inhaled corticosteroids did not reduce the antibody titer against SARS-CoV-2 spike protein. Clinicians should continue treatment with inhaled corticosteroids if indicated.

Promising Efficacy of a Third Dose of mRNA SARS-CoV-2 Vaccination in Patients Treated with Anti-CD20 Antibody Who Failed 2-Dose Vaccination.

Anti-CD20 antibodies react with CD20 expressed not only on malignant B cells, but also on normal B cells. It has been reported that patients treated with anti-CD20 antibodies had an insufficient response to two-dose mRNA SARS-CoV-2 vaccination. To investigate the efficacy of a third dose in these patients, we investigated serum IgG antibody titers for the S1 protein after a third vaccination in 22 patients treated with the anti-CD20 antibody who failed two-dose vaccination. Results showed that overall, 50% of patients seroconverted. Although no patient who received the third dose within 1 year of the last anti-CD20 antibody administration showed an increase in S1 antibody titer, 69% of patients who received the third dose more than 1 year after the last anti-CD20 antibody administration seroconverted. Our data show that a third dose of vaccination is effective in improving the seroconversion rate in patients treated with the anti-CD20 antibody who failed standard two-dose vaccination.

Identification of Breast Cancer Stem Cells Using a Newly Developed Long-acting Fluorescence Probe, C5S-A, Targeting ALDH1A1.

BACKGROUND/AIM: Aldehyde dehydrogenase (ALDH) 1A1 is a well-known marker for cancer stem cells (CSCs), characterized by self-renewal capacity and multidrug resistance in breast cancer. We developed a near-infrared turn-on fluorescence probe for ALDH1A1, C5S-A, which is suitable for observing and analyzing viable cells. Here, we demonstrated the utility of C5S-A in CSC research using breast cancer cell lines. MATERIALS AND METHODS: To evaluate concordance between C5S-A and conventional stem cell markers, breast cancer cells sorted for ALDEFLUOR-positive cells and for CD44+/CD24- cell populations were stained with C5S-A. Tumorigenicity of C5S-A-positive cells was examined by mammosphere formation assay and subcutaneous transplantation to immunodeficient mice. Additionally, to determine how long fluorescence from a single staining remained observable, we cultured breast cancer cells for 5 days after C5S-A staining. We then evaluated whether C5S-A-positive cells possessed resistance to cytotoxic drugs by chronological imaging. RESULTS: C5S-A staining showed good concordance with conventional breast CSC markers, and good utility for research into CSC characteristics in breast cancer cell lines, including tumorigenesis. Additionally, C5S-A was observable for more than 3 days with a single staining. Using this property, we then confirmed that C5S-A-positive cells possessed resistance to cytotoxic drugs, which is one of the characteristics of CSCs. CONCLUSION: We showed that C5S-A is suitable for CSC research using breast cancer cell lines, and confirmed its utility in observing cells over time.

Apixaban in Japanese patients with cancer-associated venous thromboembolism: a multi-center phase II trial.

BACKGROUND: Recent pivotal phase III trials involving direct oral anticoagulant (DOAC) versus low molecular weight heparin have demonstrated the utility of DOACs in Western patients with cancer-associated venous thromboembolism (VTE). However, these trials did not include Japanese patients. This phase II trial evaluated the safety and efficacy of apixaban in Japanese patients with cancer-associated VTE (UMIN000028447). METHOD AND RESULTS: Apixaban was initiated at 10 mg twice daily for 7 days, followed by 5 mg twice daily for 23 weeks. The primary endpoint was the incidence of major or clinically relevant non-major (CRNM) bleeding events during the treatment period. The study was terminated due to safety concerns after enrolling 27 patients. Median age was 71 years; median body weight was 51.3 kg; and major primary tumor sites were the gastrointestinal tract (26%) and lung (19%). During the median follow-up period of 5.4 months, major or CRNM bleeding occurred in in 26% of patients (major, n = 5; CRNM, n = 2; 95% confidence interval, 11-46%). No recurrent VTE or VTE-related death occurred. Estimated overall survival at 6 months was 68%. CONCLUSION: This study demonstrated the excessive bleeding risk of apixaban at the standard dose in Japanese patients with cancer-associated VTE.