M2 tumor-associated macrophages promote tumor progression in non-small-cell lung cancer.

Tumor-associated macrophages (TAMs) are key components of the tumor microenvironment that can be polarized into different phenotypes, including tumor-inhibiting M1 macrophages and tumor-promoting M2 macrophages. To elucidate the biological and clinical significance of M2 TAMs in non-small-cell lung cancer (NSCLC), a comprehensive clinical assessment of the tissue distribution of M2 TAMs was performed. The tissue distribution of M2 TAMs was retrospectively analyzed using CD163 immunohistochemistry in 160 consecutive patients who underwent NSCLC resection. Tumor proliferation was evaluated via the Ki-67 proliferation index. The results revealed that the stromal density of M2 TAMs was significantly associated with the C-reactive protein (CRP) level (P=0.0250), the Ki-67 proliferation index (P=0.0090) and invasive size (P=0.0285). Furthermore, the stromal M2 TAM density was significantly associated with tumor differentiation (P=0.0018), lymph node metastasis (P=0.0347) and pathological stage (P=0.0412). The alveolar M2 TAM density was also significantly associated with the CRP level (P=0.0309), invasive size (P<0.0001), tumor differentiation (P=0.0192), tumor status (P=0.0108) and pathological stage (P=0.0110). By contrast, no association was observed between islet M2 TAM density and the aforementioned biological and clinical factors. In regards to prognosis, disease-free survival rate was significantly lower in patients with stromal M2 TAM-high tumors (P=0.0270) and in those with alveolar M2 TAM-high tumors (P=0.0283). Furthermore, the overall survival rate was also significantly lower in patients with stromal M2 TAM-high tumors (P=0.0162) and in those with alveolar M2 TAM-high tumors (P=0.0225). Therefore, during NSCLC progression, M2 TAMs may induce tumor cell aggressiveness and proliferation and increase metastatic potential, resulting in a poor prognosis in patients with NSCLC.

PD-L1 expression on tumor-infiltrating immune cells is highly associated with M2 TAM and aggressive malignant potential in patients with resected non-small cell lung cancer.

OBJECTIVES: PD-L1 expression on tumor cells (TCs) and tumor-infiltrating immune cells (ICs) plays important roles in regulating the antitumor T cell response. However, the mechanistic and clinical significance of the effect of PD-L1 on TCs versus ICs remains unclear. On the other hand, tumor-associated macrophages (TAMs), M2 macrophages in particular, can promote tumor progression. METHODS: We evaluated PD-L1 expression on TCs and ICs using Ventana SP263 assay and the stromal M2 TAM distribution using CD163 staining in 160 consecutive patients with resected non-small cell lung cancer (NSCLC). RESULTS: PD-L1 expression on TCs and ICs was significantly higher in stromal M2 TAM-high group than in stromal M2 TAM-low group (p < 0.001 and p < 0.001, respectively). Regarding the clinical significance of PD-L1, PD-L1 expression on TCs was significantly associated with histology (p = 0.001), tumor differentiation (p < 0.001) and nodal status (p = 0.029). Furthermore, PD-L1 expression on ICs was significantly associated with histology (p < 0.001), tumor differentiation (p < 0.001), tumor status (p = 0.024), nodal status (p = 0.016), and pathologic stage (p = 0.004). The disease-free survival rate was significantly lower in patients with PD-L1-positive TC than in those with PD-L1-negative TC (p = 0.023), as well as in patients with PD-L1-positive IC than in those with PD-L1-negative IC (p < 0.001). Furthermore, the overall survival rate was significantly lower in patients with PD-L1-positive IC than in those with PD-L1-negative IC (p = 0.023). CONCLUSIONS: During tumor progression in NSCLC, the presence of M2 TAMs might affect PD-L1 expression both on TCs and ICs. In patients with NSCLC, PD-L1 expression both on TCs and ICs was associated with malignant behaviors, which was more in case of ICs.

Boron-Dependent Translational Suppression of the Borate Exporter BOR1 Contributes to the Avoidance of Boron Toxicity.

Boron (B) is an essential element for plants; however, as high B concentrations are toxic, B transport must be tightly regulated. BOR1 is a borate exporter in Arabidopsis (Arabidopsis thaliana) that facilitates B translocation into shoots under B deficiency conditions. When the B supply is sufficient, BOR1 expression is down-regulated by selective degradation of BOR1 protein, while additional BOR1 regulatory mechanisms are proposed to exist. In this study, we identified a novel B-dependent BOR1 translational suppression mechanism. In vivo and in vitro reporter assays demonstrated that BOR1 translation was reduced in a B-dependent manner and that the 5'-untranslated region was both necessary and sufficient for this process. Mutational analysis revealed that multiple upstream open reading frames in the 5'-untranslated region were required for BOR1 translational suppression, and this process depended on the efficiency of translational reinitiation at the BOR1 open reading frame after translation of the upstream open reading frames. To understand the physiological significance of BOR1 regulation, we characterized transgenic plants defective in either one or both of the BOR1 regulation mechanisms. BOR1 translational suppression was induced at higher B concentrations than those triggering BOR1 degradation. Plants lacking both regulation mechanisms exhibited more severe shoot growth reduction under high-B conditions than did plants lacking BOR1 degradation alone, thus demonstrating the importance of BOR1 translational suppression. This study demonstrates that two mechanisms of posttranscriptional BOR1 regulation, each induced under different B concentrations, contribute to the avoidance of B toxicity in plants.

Prognostic impact of preoperative monocyte counts in patients with resected lung adenocarcinoma.

OBJECTIVES: Increasing evidence suggests that an elevated peripheral monocyte count at presentation predicts a poor prognosis in various types of malignancy, including malignant lymphoma. In lung adenocarcinoma, tumor-associated macrophages (TAMs) were reported to be associated with a poor prognosis. However, it is unknown if an elevated peripheral monocyte count is associated with a poor prognosis in lung adenocarcinoma. This study assessed the prognostic impact of the preoperative peripheral monocyte count in lung adenocarcinoma. MATERIALS AND METHODS: We retrospectively analyzed 302 consecutive patients with lung adenocarcinoma who received curative resection at Kitano Hospital. The receiver operating characteristic (ROC) curve for the peripheral monocyte count was used to determine the cut-off value. The relations between peripheral monocyte counts and clinicopathological factors were assessed. We also evaluated the impacts of possible prognostic factors including the preoperative peripheral monocyte count on survival, using the two-tailed log-rank test and Cox proportional hazards model. In addition, immunohistochemical staining for CD68 was performed to evaluate the monocytes in primary tumors. RESULTS: A peripheral monocyte count of 430mm(-3) was the optimal cut-off value for prognosis. An elevated peripheral monocyte count was significantly associated with sex, performance status, smoking history, chronic obstructive pulmonary disease and interstitial lung disease. The two-tailed log-rank test demonstrated that patients with an elevated peripheral monocyte count experienced a poorer recurrence-free survival (RFS) and overall survival (OS) (P=0.0063, P<0.0001, respectively). In the multivariate analysis an elevated peripheral monocyte count was shown to be an independent prognostic factor for the RFS and OS (HR: 1.765; 95% CI: 1.071-2.910; P=0.0258, HR: 4.339; 95% CI: 2.032-9.263; P=0.0001, respectively). Furthermore, numbers of the monocytes in primary tumors significantly correlated with peripheral monocyte counts (r=0.627, P<0.0001). CONCLUSION: The preoperative peripheral monocyte count is an important prognostic factor for patients with lung adenocarcinoma after curative resection.

Bone marrow-derived mononuclear cell transplantation in spinal cord injury patients by lumbar puncture.

PURPOSE: This study was conducted to assess the safety and feasibility of intrathecal transplantation of autologous bone marrow-derived mononuclear cells for the treatment of patients with spinal cord injury. METHODS: Ten patients were included in the study. Approximately 120 ml of bone marrow aspirate was obtained from bilateral iliac bone of patients with spinal cord injury. Isolation of mononuclear cells was performed using Ficoll density-gradient centrifugation. Bone marrow mononuclear cells were transplanted into cerebrospinal fluid by lumbar puncture. Functional tests were performed prior to the cell transplantation and six months after cell transplantation. The patients were carefully observed for up to six months. RESULTS: In 5 patients with AIS A prior to cell transplantation, 1 patient converted to AIS B six months after cell transplantation. In 5 patients with AIS B, 1 patient converted to AIS D and 2 patients to AIS C. MRI did not show any complication. Two patients showed slight anemia after aspiration of bone-marrow cells, which returned to normal level within a several weeks. CONCLUSION: The results of this study suggest that this method may be safe and feasible.

Prognostic significance of the immediate early response gene X-1 (IEX-1) expression in pancreatic cancer.

BACKGROUND: The immediate early response gene X-1 (IEX-1) is a stress-inducible protein that is involved in the regulation of cell proliferation and apoptosis. The aim of this study was to evaluate the prognostic significance of IEX-1 expression in pancreatic cancer. METHODS: IEX-1 protein expression was examined on paraffin-embedded specimens from 78 patients with pancreatic ductal adenocarcinoma using immunohistochemistry. The relationships between the IEX-1 expression and other clinicopathological parameters and patient survival were evaluated. A similar analysis was conducted in a subgroup of 48 patients, who underwent a macroscopically curative resection with detailed information on the pathological findings. RESULTS: Among 78 pancreatic cancer patients, 41 patients (53%) were positive for IEX-1 staining. In a multivariate analysis, curative operation (P < .001), pathological stage I-III (P = .001), and positive IEX-1 expression (P = .002) were significantly favorable factors for survival. In a subgroup of 48 patients undergoing a macroscopically curative surgery, IEX-1 expression was positive in 28 patients (58%). A significant negative correlation was observed between the IEX-1 expression and serosal (P = .032) or arterial (P = .040) invasion of tumors. A multivariate analysis demonstrated limited local invasion (pT1-3, P = .021), negative lymph node involvement (pN0, P < .001), and positive IEX-1 expression (P = .004) to be significantly favorable factors for survival. CONCLUSIONS: The positive IEX-1 expression in tumor tissues may be associated with a better prognosis in pancreatic cancer. An immunohistochemical assessment of IEX-1 expression may therefore be helpful for predicting patient prognosis in this disease.

Clinical significance of aminopeptidase N in non-small cell lung cancer.

PURPOSE: The aim of our study is to investigate the mechanism of metastasis, to detect novel metastasis-associated molecules, and to evaluate the molecules from the point of view of clinical application. A monoclonal antibody MH8-11, which we established, recognizes a glycoprotein that is identical to aminopeptidase N (APN/CD13). APN/CD13 degrades the extracellular matrix, while it is also involved in cell motility and improves angiogenesis. EXPERIMENTAL DESIGN: We investigated the expression of APN/CD13 in 194 cases of non-small cell lung cancer (NSCLC) by immunohistochemical analyses and reverse transcription-PCR assay to determine the significance of this prognostic factor; 95 tumors were stage I, 36 were stage II, 39 were stage IIIA, and 24 were stage IIIB. Moreover, we investigated that the relationship between the expression of APN/CD13 and angiogenesis and prognosis for patients with NSCLC. RESULTS: We found a correlation between the expression of APN/CD13 and angiogenesis (r = 0.659; P < 0.0001). In the 194 patients with NSCLC, we found 68 patients to be APN/CD13+ and 126 patients to be APN/CD13-. The 5-year survival rate in patients with APN/CD13+ tumors was significantly lower than in those whose tumors had negative APN/CD13 (48.3% versus 67.1%; P = 0.0001). CONCLUSION: Our data suggest the expression of APN/CD13 for patients with NSCLC to be associated with a poor prognosis and angiogenesis. This is the first study to show the relationship between the expression of APN/CD13 and the prognosis of patients with NSCLC. The inhibition of APN/CD13 may be an effective new molecular target therapy for patients with NSCLC.

Ran, a small GTPase gene, encodes cytotoxic T lymphocyte (CTL) epitopes capable of inducing HLA-A33-restricted and tumor-reactive CTLs in cancer patients.

PURPOSE: The purpose is to identify a gene coding for tumor-associated antigen and peptide capable of inducing CTLs reactive to tumor cells with a HLA-A33-restricted fashion to provide scientific basis for specific immunotherapy to HLA-A33+ cancer patients. EXPERIMENTAL DESIGN: An expression gene-cloning method was used to identify the tumor-associated antigen gene. Northern blot analysis and immunohistochemistry were used to examine the mRNA and protein expression levels in various cells and tissues, respectively. Synthetic peptides were examined for their ability to induce HLA-A33+ tumor-reactive CTLs in peripheral blood mononuclear cells from cancer patients. RESULT: A gene of small GTPase, Ran, which controls the cell cycle through the regulation of nucleocytoplasmic transport, mitotic spindle organization, and nuclear envelope formation, was found to encode epitopes recognized by the HLA-A33-restricted CTLs established from T cells infiltrating into gastric adenocarcinoma. The expression of the Ran gene was increased in most cancer cell lines and cancer tissues at both the mRNA and protein levels. However, it was not enhanced in the surrounding normal cells or tissues. It was also undetectable in normal tissues as far as tested. Ran-derived peptides at positions 48-56 and 87-95 could induce CD8+ peptide-specific CTLs reactive to tumor cells from HLA-A33+ epithelial cancer patients in a HLA class I-restricted manner. CONCLUSIONS: Because of its increased expression in cancer cells and involvement in malignant transformation and/or the enhanced proliferation of cancer cells, the two Ran-directed peptides could be potent candidates in use for specific immunotherapy against HLA-A33+ epithelial cancers.

Expression of cell cycle related proteins in a rapidly growing uveal malignant melanoma.

PURPOSE: To report the clinical and immunohistochemical findings of a rapidly growing uveal melanoma. METHODS: A 71-year-old Japanese woman was diagnosed with a juxtapapillary uveal melanoma by clinical examination. The tumor grew rapidly with a 31.5-day doubling time. An enucleation was performed, and immunohistochemical examination for cell cycle proteins was performed in addition to routine histopathologic examination. RESULTS: The melanoma cells were classified as spindle B-cells. The tumor cells were positive for HMB-45 protein, but negative for S-100 protein. The tumor showed immunohistochemical staining for p16 and Bcl-2, although p53 was not detected. Immunoreactivity for pRb was found in normal retinal and choroidal cells but not in the tumor cells. CONCLUSION: This report describes a unique case of rapidly growing uveal melanoma, which showed low histopathologic grade while the cell cycle protein immunohistochemical profile suggests a more aggressive phenotype. The evaluation of cell cycle proteins may be useful adjunctive method to enhance the understanding of uveal melanoma growth patterns.

Immediate early response gene X-1, a stress-inducible antiapoptotic gene, encodes cytotoxic T-lymphocyte (CTL) epitopes capable of inducing human leukocyte antigen-A33-restricted and tumor-reactive CTLs in gastric cancer patients.

Peptide-based vaccine therapy, which is designed to elicit T-cell immunity against tumors, is an attractive approach for the treatment of cancer patients. To provide a scientific basis for peptide therapy, an increasing number of CTL-directed peptides have been identified, and some of them have been tried as antigen-specific immunotherapy in the past decade. Only a few studies, however, have been performed on such peptides restricted with alleles other than HLA-A2 and -A24. In the present study, we show that immediate early response gene X-1 (IEX-1), a stress-inducible protein associated with the regulation of cell proliferation and apoptosis, produces antigenic epitopes recognized by 850B-CTLs, HLA-A33-restricted CTLs newly established from T cells infiltrating into gastric adenocarcinoma. The IEX-1 gene was highly expressed in most cell lines and tissues from various types of cancer at both the mRNA and protein levels. However, it was not expressed at the protein level in any normal epithelium or connective tissues tested. Three IEX-1-derived peptides at positions 47-56, 61-69, and 65-73, which were recognized by the 850B-CTLs, could induce CD8(+) peptide-specific CTL reaction to tumor cells from HLA-A33(+) gastric cancer patients and other epithelial cancer patients, but not from healthy donors, in an HLA class I-restricted manner. Because increased expression of IEX-1 is suggested to be involved in the resistance to apoptosis and in the proliferation of cancer cells, these antigenic peptides could be potent candidates for peptide-based specific immunotherapy against HLA-A33(+) gastric cancer and other epithelial cancers.