Physical Exercise Counteracts Aging-Associated White Matter Demyelination Causing Cognitive Decline.

In the central nervous system, oligodendrocytes wrap around neuronal axons to form myelin, an insulating layer or sheath that allows for the efficient conductance of action potentials. In addition to structural insulation, myelin provides encased axons with nutrient, metabolic and defensive support. Demyelination, or myelin loss, can therefore cause axonal dysfunction, leading to neurological impairment and disease. In Alzheimer's disease (AD), progressive white matter demyelination is acknowledged as one of the earliest pathologies preceding symptom onset. Unfortunately, current pharmacotherapy for slowing demyelination or promoting remyelination in AD is nonexistent. Exercise is recognized for its wide-ranging benefits to human health, including improved mental health and the prevention of lifestyle-related diseases. Mounting evidence suggests the contribution of physical activity in delaying the progression of dementia in elderly populations. Recent mechanistic studies have shown that exercise facilitates myelination in the brain through the vitalization of intrinsic pro-myelination cues, such as increased neurotrophic factors and electrical activity. In this review, we summarize and discuss the potential of physical exercise on counteracting aging-associated white matter demyelination, which causes cognitive decline in AD. We highlight the need of further basic and clinical research investigations on this topic to establish novel approaches for healthy and improved brain aging.

Analysis of the chemotactic factors for tumor-infiltrating fibrocytes and their prognostic significances in lung cancer.

Fibrocytes, which are bone marrow-derived collagen-producing cells, have been reported to be involved in pathogenesis of pulmonary fibrosis. Our previous study reported that tumor-infiltrating fibrocytes play a role in tumor progression and drug resistance in lung cancer. The present study therefore examined chemotactic factors for fibrocytes in tissues of non-small cell lung cancer (NSCLC) and their prognostic significance. Surgically resected tumor tissues were examined for the expression of chemotactic factors, including C-X-C motif chemokine 12 (CXCL12), CCL2, platelet-derived growth factor (PDGF)-AA and PDGF-BB, as well as tumor-infiltrating fibrocytes by immunostaining. The chemotactic ability of fibrocytes in response to each factor was evaluated using a migration assay by counting the migrated cells microscopically, and expression of receptors for chemotactic factors were analyzed by flow cytometry. The expression of CXCL12, but not CCL2, PDGF-AA, or PDGF-BB, was associated with the number of tumor-infiltrating fibrocytes in lung adenocarcinoma (LUAD), but not lung squamous cell carcinoma (LUSQ). In addition, patients with an increased expression of CXCL12 in LUAD but not LUSQ showed a significantly poorer prognosis compared with those with a decreased expression. However, the expression of CCL2, PDGF-AA and PDGF-BB was not correlated with the prognosis of patients with NSCLC. The number of fibrocytes was associated with a poor prognosis in LUAD. Fibrocytes derived from the peripheral blood of healthy subjects as well as patients with lung cancer expressed higher levels of CXCR4 compared with CCR2, PDGF and receptor-α and receptor-ß. Overall, these results suggested that targeting tumor-infiltrating fibrocytes via the CXCL12/CXCR4 axis may be a useful strategy for controlling the progression of NSCLC, particularly LUAD.

A 44-Year-Old Alcohol-Dependent Man Who Recovered from Central Pontine Myelinolysis with Supportive Physical Therapy.

BACKGROUND Central pontine myelinolysis (CPM) includes symmetric demyelination of the central pons. CPM is a rare neurological disorder that generally develops after rapid correction of hyponatremia in individuals having underlying conditions, such as malnutrition, alcoholism, and severe burns. It can cause severe long-term disabilities. However, there is currently no pharmacotherapy capable of promoting remyelination, a process crucial for recovery from CPM. We present the case of a patient with alcoholism and malnutrition-related CPM, which developed following rapid correction of hyponatremia but then improved remarkably with supportive physical therapy. CASE REPORT A 44-year-old alcoholic and malnourished man was admitted to an emergency hospital for disorientation due to overdrinking, but later developed bulbar palsy after hyponatremia was unexpectedly, but rapidly, corrected. Axial scans of the diffusion-weighted brain MRI revealed a characteristic lesion known as a piglet sign in the central pons. Based on his underlying conditions, present episode of sodium correction, and MRI finding, the patient was diagnosed as having CPM, which progressively worsened, resulting in locked-in syndrome after 12 days. The patient was then transferred to a long-term care unit and received simple motion exercise daily, but no specific medication. His symptoms gradually improved, achieving discontinuation of tube feeding on day 21, independent walking on day 110, and discharge after 6 months. CONCLUSIONS This report highlights the importance of physical therapy, the potential of which is often underestimated despite its broad benefits for human health, as a readily applicable intervention for patients with CPM. Further understanding of mechanisms underlying exercise-induced myelination should contribute to establishing novel therapies for a wide spectrum of brain disorders.

Radiation-associated Angiosarcoma Presenting as Massive Pleural Effusion.

A 67-year-old man was admitted to our hospital for massive pleural effusion. He had a history of mandibular gingival carcinoma treated with radiation therapy (RT). Based on the cytology findings of pleural effusion and a thoracoscopic pleural biopsy, we finally diagnosed him with radiation-associated angiosarcoma. Retrospective cell-block immunocytochemistry with pleural effusion also showed potential utility for the diagnosis. This case highlights the importance of considering the possibility of radiation-associated secondary cancer in patients with pleural effusion who have a history of RT.

Blockade of PD-1/PD-L1 Pathway Enhances the Antigen-Presenting Capacity of Fibrocytes.

Fibrocytes, a distinct population of collagen-producing, monocyte-derived cells, are involved in wound healing as well as fibrotic diseases. Recently, fibrocytes have been revealed to play a role in the tumor microenvironment, particularly under antiangiogenic therapy. In addition, combination cancer immunotherapy with immune checkpoint inhibitor and antiangiogenic agents have been developed for various cancers in the clinical setting, although the immunological background is not clear. In the current study, we aimed to determine the function of fibrocytes in tumor immunity induced by immune checkpoint inhibitor therapy. Human and murine fibrocytes were generated from PBMCs and lungs, respectively. The expression of costimulatory and inhibitory molecules on fibrocytes was examined by flow cytometry. The stimulation of CD8+ T cells by fibrocytes was examined in MLRs with a 3H-thymidine incorporation assay. Fibrocytes expressed CD80low and CD86high as a costimulatory molecule, and expressed PD-L1high, but not PD-L2, as a coinhibitory molecule. Without any stimulation, fibrocytes strongly enhanced the proliferation of CD8+ T cells in mice and humans. Treatment with anti-CD86 and -CD54 Abs inhibited the growth of CD8+ T cells induced by fibrocytes. Anti-PD-L1 Ab further enhanced the proliferation of CD8+ T cells, even in the OVA-specific MLR with OT-1Rag-/- mice. Importantly, fibrocytes derived from PBMCs of patients with lung adenocarcinoma or murine MC38 tumors augmented the proliferation of CD8+ T cells with PD-L1 blockade. These results suggest that fibrocytes infiltrating tumor sites may play a role in the antitumor immunity mediated by CD8+ T cells when the activity is further enhanced by PD-L1/PD-1 blockade.

Anti-PD-1 antibody combined with chemotherapy suppresses the growth of mesothelioma by reducing myeloid-derived suppressor cells.

BACKGROUND: The combination of anti-PD-1/PD-L1 antibody with chemotherapy has been approved for the first-line therapy of lung cancer. However, the effects against malignant mesothelioma (MPM) and the immunological mechanisms by which chemotherapy enhances the effect of targeting PD-1/PD-L1 in MPM are poorly understood. MATERIALS AND METHODS: We utilized syngeneic mouse models of MPM and lung cancer and assessed the therapeutic effects of anti-PD-1 antibody and its combination with cisplatin (CDDP) and pemetrexed (PEM). An immunological analysis of tumor-infiltrating cells was performed with immunohistochemistry. RESULTS: We observed significant therapeutic effects of anti-PD-1 antibody against MPM. Although the effect was associated with CD8+ and CD4+ T cells in tumors, the number of Foxp3+ cells was not reduced but rather increased. Consequently, combination with CDDP/PEM significantly enhanced the antitumor effects of anti-PD-1 antibody by decreasing numbers of intratumoral myeloid-derived suppressor cells (MDSCs) and vessels probably through suppression of VEGF expression by CDDP + PEM. CONCLUSIONS: The combination of anti-PD-1 antibody with CDDP + PEM may be a promising therapy for MPM via inhibiting the accumulation of MDSCs and vessels in tumors.

Development, validation, and comparison of gene analysis methods for detecting EGFR mutation from non-small cell lung cancer patients-derived circulating free DNA.

The feasibility and required sensitivity of circulating free DNA (cfDNA)-based detection methods in second-line epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) treatment are not well elucidated. We examined T790M and other activating mutations of EGFR by cfDNA to assess the clinical usability. In 45 non-small cell lung cancer (NSCLC) patients harboring activating EGFR mutations, cfDNAs were prepared from the plasma samples. EGFR mutations in cfDNA were detected using highly sensitive methods and originally developed assays and these results were compared to tissue-based definitive diagnoses. The specificity of each cfDNA-based method ranged 96-100% whereas the sensitivity ranged 56-67%, indicating its low pseudo-positive rate. In EGFR-TKI failure cohort, 41-46% samples were positive for T790M by each cfDNA-based method, which was comparable to re-biopsy tissue-based T790M positive rates in literature. The concordance of the results for each EGFR mutation ranged from 83-95%. In eight patients, the results of the cfDNA-based assays and re-biopsy-derived tissue-based test were compared. The observed overall agreement ranged in 50-63% in T790M, and in 63-100% in activating EGFR mutations. In this study, we have newly developed three types of assay which have enough sensitivity to detect cfDNA. We also detected T790M in 44% of patients who failed prior EGFR-TKI treatment, indicating that cfDNA-based assay has clinical relevance for detecting acquired mutations of EGFR.

A case of interstitial pneumonia associated with anti-PL-7 antibody in a patient with rheumatoid arthritis.

A 65-year-old female had been treated rheumatoid arthritis (RA), interstitial pneumonia (IP) and nephrotic syndrome with prednisolone and cyclosporine. She was emergently admitted to our hospital due to the worsening exertional dyspnea and severe hypoxemia. Chest computed tomography (CT) showed new diffuse ground-glass opacities (GGOs) with slight consolidations along with bronchovascular bundle were observed in addition to pre-existing reticular shadows in both lungs with lower lobe-predominance. An acute exacerbation (AE) of pre-existing IP triggered by an infection was suspected, and the treatment with antibiotics and corticosteroid pulse therapy improved her general condition and chest radiological findings. Because some auto-antibodies associated with acute/subacute onset IP have recently become available in clinic, we examined those including anti-aminoacyl tRNA synthetase (ARS) antibodies, and found that she was positive for anti-PL-7 antibody. We diagnosed her anti-synthetase syndrome (ASS) without symptom of myositis, and her IP was considered to be ASS-related. The careful consideration is necessary to precisely diagnose and treat the patients with RA-associated interstitial lung diseases as the several etiologies may be overlapped in the same patient. J. Med. Invest. 65:147-150, February, 2018.

Analysis of the Prognostic Factors of Extensive Disease Small-Cell Lung Cancer Patients in Tokushima University Hospital.

BACKGROUND: Small-cell lung cancer (SCLC) presents aggressive clinical behavior, and its prognosis is still poor. Previously, performance status (PS), or the existence of brain, bone, or liver metastasis were reported to be unfavorable prognostic factors. Given the recent progress of treatment modalities such as radiotherapy techniques and bone modifying agents, the prognostic factors might be different from previous findings. Therefore, we analyzed the prognostic factors of extensive disease SCLC (ED-SCLC) in recent years. METHODS: ED-SCLC patients treated in Tokushima University Hospital between 2010 and 2016 were analyzed. Log-rank test and the Cox proportional hazards regression model was used in univariate and multivariate analysis, respectively. RESULTS: Totally, 79 patients were analyzed. In the univariate analysis, age, PS, interstitial pneumonia (IP), liver metastasis, pleural dissemination, neutrophil counts, hypoalbuminemia, hypercalcemia and several liver and biliary enzymes were identified as poor prognostic factors. In the multivariate analysis, age, PS, IP, and liver and biliary enzymes were identified. Moreover, the PS in patients with liver metastasis was significantly worsened. CONCLUSIONS: In this study, we newly demonstrated that IP was a significant poor prognostic factor of ED-SCLC. Although liver metastasis was not extracted in multivariate analysis, it may have an impact on the prognosis of ED-SCLC. J. Med. Invest. 63: 286-293, August, 2016.

Antitumor effect of novel anti-podoplanin antibody NZ-12 against malignant pleural mesothelioma in an orthotopic xenograft model.

Podoplanin (aggrus) is highly expressed in several types of cancers, including malignant pleural mesothelioma (MPM). Previously, we developed a rat anti-human podoplanin mAb, NZ-1, and a rat-human chimeric anti-human podoplanin antibody, NZ-8, derived from NZ-1, which induced antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity against podoplanin-positive MPM cell lines. In this study, we showed the antitumor effect of NZ-1, NZ-8, and NZ-12, a novel rat-human chimeric anti-human podoplanin antibody derived from NZ-1, in an MPM orthotopic xenograft SCID mouse model. Treatment with NZ-1 and rat NK (CD161a(+) ) cells inhibited the growth of tumors and the production of pleural effusion in NCI-H290/PDPN or NCI-H226 orthotopic xenograft mouse models. NZ-8 and human natural killer (NK) (CD56(+) ) cells also inhibited tumor growth and pleural effusion in MPM orthotopic xenograft mice. Furthermore, NZ-12 induced potent ADCC mediated by human MNC, compared with either NZ-1 or NZ-8. Antitumor effects were observed following treatment with NZ-12 and human NK (CD56(+) ) cells in MPM orthotopic xenograft mice. In addition, combined immunotherapy using the ADCC activity of NZ-12 mediated by human NK (CD56(+) ) cells with pemetrexed, led to enhanced antitumor effects in MPM orthotopic xenograft mice. These results strongly suggest that combination therapy with podoplanin-targeting immunotherapy using both NZ-12 and pemetrexed might provide an efficacious therapeutic strategy for the treatment of MPM.

BCG-induced pneumonitis with lymphocytic pleurisy in the absence of elevated KL-6.

BACKGROUND: Pneumonitis is a rare complication of bacillus Calmette-Guerin (BCG) immunotherapy seen in patients with urothelial cancer following the repeated administration of BCG. However, no case of BCG-induced pleurisy has been reported. CASE PRESENTATION: We here report the first case of pneumonitis with lymphocytic pleurisy following bacillus Calmette-Guerin (BCG) immunotherapy. Although marked T helper cell alveolitis was found by bronchoalveolar lavage and transbronchial biopsies, no acid-fast bacillus could be identified in recovered BALF or pleural effusion. The lymphocyte stimulation test of BCG was strongly positive. However, levels of serum and bronchoalveolar lavage fluid KL-6, a useful marker for hypersensitivity pneumonitis (HP), were within normal ranges. CONCLUSION: We speculate that the pathogenesis of our case may be a hypersensitive reaction to the proteic component of BCG entering the lung and pleural space, which is different from the etiology of the common type of HP.

CD5-positive diffuse large B cell lymphoma infiltrating the central nervous system presenting Guillain-Barré-like syndrome after chemotherapy.

An 83-year-old woman was admitted to our hospital with abdominal pain. Examination revealed mediastinal lymphoadenopathy, hepatosplenomegaly, and infiltration of abnormal cells into the bone marrow with hemophagocytosis, and CD5-positive diffuse large B cell lymphoma was diagnosed. Chemotherapy was administered and progressive weakness of the limbs, resembling a Guillain-Barré-like syndrome, subsequently appeared. Cerebrospinal fluid examination indicated lymphoma cell infiltration. Although immune globulin and steroid therapies were not effective, intrathecal injection of methotrexate, predonisolone, and cytarabine improved these symptoms. Subsequent to chemotherapy, cell surface antigen changes were observed in the cerebrospinal fluid relative to those in bone marrow.

[Exacerbation of cranial nerurological symptoms by platelet transfusion before the diagnosis of thrombotic thrombocytopenic purpura].

A 47-year-old woman was transported to our hospital because of vomiting and syncope after breakfast. Physical examination revealed icterus and anemia of bulbar conjunctivas, and abnormal neurological findings were detected. Laboratory data indicated marked anemia and thrombocytopenia (Hb 5.2 g/dl, Plt. 0.6×10(4)/µl), but no leukocyte abnormalities were found. Transaminase was slightly elevated, and serum indirect bilirubin in was also elevated. Based on these data, we initially suspected Evan's syndrome, which involves idiopathic thrombocytopenic purpura with autoimmune hemolytic anemia. So we transfused red blood cells, performed platelet transfusion, and administered steroids, but there was no response to these therapies. On the 4th day of admission, she developed a stroke followed by coma. After the stroke, we diagnosed the case as thrombotic thrombocytopenic purpura (TTP) because laboratory findings showed diminished activity of ADAMTS 13 (a disintegrin-like metalloproteinase with thrombospondin type 1 motifs 13) and ADAMTS 13 antigen. It is important to suspect TTP when hemolytic anemia with thrombocytopenia is observed, and to check the activity and antigen of ADAMTS13 immediately for the diagnosis. Platelet transfusion should be done cautiously in these cases.

[Historical aspect of molecular-targeted therapy for cancer].

Recently, discovery and identification of critical molecules responsible for cancer progression lead to development of specific target-directed therapies, including monoclonal antibodies and small molecular compounds. For the past 15 years, the advent of target-specific therapeutics has remarkably improved the clinical outcomes of certain patients with various malignancies, and it was followed by the understanding of mechanism of the drug resistance. Moreover, useful biomarkers were developed to further increase the power of patient selection for molecular-targeted therapy. From the historical point of view, we review the progress in developing new molecular-targeted drugs for personalized medicine.