Potential biomarker enhancing the activity of tuberculosis, hsa-miR-346.

OBJECTIVES: To determine the usefulness of hsa-miR-346, a potential biomarker enhancing the activity of non-tuberculous mycobacterial diseases, as a biomarker of tuberculosis activity. METHODS: We investigated whether hsa-miR-346 is secreted by human macrophages infected with Mycobacterium tuberculosis (M. tuberculosis) in an in vitro study. In addition, a cross-sectional study was conducted first to evaluate whether serum hsa-miR-346 is elevated in patients with tuberculosis compared with that in healthy individuals. Second, we conducted a retrospective study to evaluate whether anti-tuberculosis treatment reduces serum hsa-miR-346 levels. RESULTS: Log hsa-miR-346 levels were significantly elevated in the supernatant of human macrophages infected with M. tuberculosis in a dose-dependent manner. The mean serum log hsa-miR-346 levels were -15.48 (-15.76 to -15.21) in patients with tuberculosis and -16.12 (-16.29 to -15.95) in healthy volunteers, which significantly differed. In addition, hsa-miR-346 significantly decreased at 2 months from starting an anti-tuberculosis treatment. CONCLUSIONS: We consider hsa-miR-346 as a potential biomarker enhancing the tuberculosis activity.

Seeking high-priority mutations enabling successful antibody-breeding: systematic analysis of a mutant that gained over 100-fold enhanced affinity.

"Antibody-breeding" has provided therapeutic/diagnostic antibody mutants with greater performance than native antibodies. Typically, random point mutations are introduced into the VH and VL domains of parent antibodies to generate diverse libraries of single-chain Fv fragments (scFvs), from which evolved mutants are selected. We produced an scFv against estradiol-17ß with 11 amino acid substitutions and a >100-fold improved affinity constant (Ka = 1.19 × 1010 M-1) over the parent scFv, enabling immunoassays with >30-fold higher sensitivity. We systematically analyzed contributions of these substitutions to the affinity enhancement. Comparing various partial scFv revertants based on their Kas indicated that a revertant with four substitutions (VH-L100gQ, VL-I29V, -L36M, -S77G) exhibited somewhat higher affinity (Ka = 1.46 × 1010 M-1). Finally, the VH-L100gQ substitution, occurring in VH complementarity-determining region (CDR) 3, was found to be the highest-priority for improving the affinity, and VL-I29V and/or VL-L36M cooperated significantly. These findings encouraged us to reconsider the potential of VH-CDR3-targeting mutagenesis, which has been frequently attempted. The substitution(s) wherein might enable a "high rate of return" in terms of selecting mutants with dramatically enhanced affinities. The "high risk" of generating a tremendous excess of "junk mutants" can be overcome with the efficient selection systems that we developed.

Disseminated histoplasmosis from a calcified lung nodule after long-term corticosteroid therapy in an elderly Japanese patient: A case report.

RATIONALE: Histoplasmosis occurs most commonly in Northern and Central America and Southeast Asia. Increased international travel in Japan has led to a few annual reports of imported histoplasmosis. Healed sites of histoplasmosis lung infection may remain as nodules and are often accompanied by calcification. Previous studies in endemic areas supported the hypothesis that new infection/reinfection, rather than reactivation, is the main etiology of symptomatic histoplasmosis. No previous reports have presented clinical evidence of reactivation. PATIENT CONCERNS: An 83-year-old Japanese man was hospitalized with general fatigue and high fever. He had been treated with prednisolone at 13 mg/d for 7 years because of an eczematous skin disease. He had a history of travel to Los Angeles, Egypt, and Malaysia 10 to 15 years prior to admission. Five years earlier, computed tomography (CT) identified a solitary calcified nodule in the left lingual lung segment. The nodule size remained unchanged throughout a 5-year observation period. Upon admission, his respiratory condition remained stable while breathing room air. CT revealed small, randomly distributed nodular shadows in the bilateral lungs, in addition to the solitary nodule. DIAGNOSIS: Disseminated histoplasmosis, based on fungal staining and cultures of autopsy specimens. INTERVENTIONS: The patient's fever continued despite several days of treatment with meropenem, minocycline, and micafungin. Although he refused bone marrow aspiration, isoniazid, rifampicin, ethambutol, and prednisolone were administered for a tentative diagnosis of miliary tuberculosis. OUTCOMES: His fever persisted, and a laboratory examination indicated severe thrombocytopenia with disseminated intravascular coagulation. He died on day 43 postadmission. During autopsy, the fungal burden was noted to be higher in the calcified nodule than in the disseminated nodules of the lung, suggesting a pathogenesis involving endogenous reactivation of the nodule and subsequent hematogenous and lymphatic spread. LESSONS: Physicians should consider histoplasmosis in patients with calcified nodules because the infection may reactivate during long-term corticosteroid therapy.

Efficacy of afatinib or osimertinib plus cetuximab combination therapy for non-small-cell lung cancer with EGFR exon 20 insertion mutations.

OBJECTIVES: Epidermal growth factor receptor (EGFR) mutation-positive lung cancer accounts for a significant subgroup of non-small cell lung cancers (NSCLC). Approximately 4-10% of EGFR mutations in NSCLC are EGFR exon 20 insertion mutations, which are reportedly associated with resistance to EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment. NSCLC patients carrying these mutations are rarely treated with EGFR-TKIs. The purpose of this study was to evaluate the efficacy of afatinib or osimertinib plus cetuximab combination therapy in experimental NSCLC models with EGFR exon 20 insertion mutations. MATERIALS AND METHODS: The EGFR mutations examined in this study were A763_Y764insFQEA, Y764_V765insHH, A767_V769dupASV, and D770_N771insNPG. Ba/F3 cells constitutively expressing wild type or mutated EGFR were used to determine the efficacy of afatinib or osimertinib plus cetuximab combination therapy in vitro. To determine the efficacy of the combination therapy in vivo, female BALB/c-nu mice were injected subcutaneously with 1 million Ba/F3 cells carrying EGFR A767_V769dupASV or Y764_V765insHH. RESULTS: We observed a mild but significant (P < 0.05) additive effect of the combination therapy against several EGFR exon 20 insertion mutations in vitro. Regarding EGFR A767_V769dupASV and EGFR Y764_V765insHH, cetuximab and afatinib single treatment did not induce significant inhibition of tumor formation; however, afatinib plus cetuximab combination treatment induced significant (P < 0.05) tumor growth inhibition without significant body weight loss or skin rash. CONCLUSION: The combination therapy induced a more potent inhibitory effect against several EGFR exon 20 insertion mutations than either therapy alone. Cetuximab can potentially increase the efficacy of afatinib or osimertinib in NSCLC with EGFR exon 20 insertion mutations.

Comparison of detection methods of EGFR T790M mutations using plasma, serum, and tumor tissue in EGFR-TKI-resistant non-small cell lung cancer.

BACKGROUND: Osimertinib, a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor, exerts remarkable effects against EGFR T790M resistance mutation-positive non-small cell lung cancer. Identifying T790M mutation by re-biopsy is essential before prescribing osimertinib. Tissue biopsy is the golden standard for this purpose, but several factors limit its success rate. The liquid biopsy with blood, using circulating tumor DNA, has been an alternative method. However, the true biological meaning and equivalence of liquid biopsy and tumor biopsy are still under investigation. Especially, the usefulness of serum samples to detect T790M mutation is not yet been known. PATIENTS AND METHODS: We prospectively evaluated the sensitivity, specificity, and parallelism of the detection of EGFR mutations in tissue re-biopsy and liquid biopsy (plasma and serum), simultaneously, from June 2016 to May 2017. EGFR mutations in tumor re-biopsy were evaluated by COBAS ver2 and PNA-LNA PCR clamp method, and those in liquid biopsy were evaluated with COBAS ver2. RESULTS: Fifteen patients were enrolled. In 10 patients whose EGFR mutation was detected in liquid biopsy, the original EGFR mutation (exon 19 del or L858R) was detected in all patients. Detection of EGFR mutation by COBAS ver2 and by PNA-LNA method was almost the same in tissue re-biopsy. The detection rate of T790M was lower than that of the original EGFR mutation in liquid biopsy compared to that in tissue re-biopsy. The detection of T790M in serum exhibited a higher specificity (67%) and positive predictive value (50%) than that in plasma (50% and 40%, respectively). The detection sensitivity was similar in plasma and serum. CONCLUSION: Plasma, serum, and tissue genotyping can have complementary roles for detecting EGFR-T790M using COBAS ver2. Repeated tests with different samples and different methods may improve accuracy of T790M detection and will lead to the maximum benefit for the patient.

Edoxaban treatment for pulmonary arterial thromboembolism associated with azygous vein aneurysm.

A 76-year-old woman, diagnosed 5 years previously with an asymptomatic mediastinal bronchogenic cyst, was referred to our department as the mass had grown slightly larger. Contrast-enhanced computed tomography and magnetic resonance imaging scans revealed an azygous vein aneurysm with a pulmonary arterial thromboembolism. The patient was treated with heparin for 5 days, and anticoagulation therapy with edoxaban was continued for 12 months. The thrombus resolved, and the aneurysm remained unchanged. An azygous vein aneurysm is a very rare condition that causes pulmonary arterial thromboembolism. Although surgical resection is indicated for patients with azygous vein aneurysms with a risk of rupture and pulmonary embolism, we chose anticoagulation therapy because of the patient's advanced age. This case suggests that the azygous vein aneurysm is one of the differential diagnoses for a mediastinal mass and that anticoagulation therapy can be the treatment of choice for pulmonary arterial thromboembolism with an azygous vein aneurysm.

Successful treatment of non-small-cell lung cancer with afatinib and a glucocorticoid following gefitinib- and erlotinib-induced interstitial lung disease: A case report.

Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI)-induced interstitial lung disease (ILD) may be a life-threatening condition that may develop during treatment of lung cancer patients harboring EGFR mutations. We herein present the case of a 41-year-old female patient diagnosed with lung adenocarcinoma with an EGFR mutation (exon 19 deletion). The patient was treated with gefitinib followed by erlotinib and developed ILD induced by both EGFR-TKIs; furthermore, the patient acquired resistance to EGFR-TKI treatment. A repeat biopsy revealed a T790M mutation, which is associated with resistance to first-generation EGFR-TKIs, along with an exon 19 deletion identified by cytology of the pleural fluid. Treatment with afatinib and prednisolone resulted in tumor shrinkage, without worsening of the ILD. The present case demonstrated that combination treatment with afatinib and a glucocorticoid may be effective for the treatment of lung cancer patients who develop EGFR-TKI-induced ILD.