Inhibition of PTPN3 Expressed in Activated Lymphocytes Enhances the Antitumor Effects of Anti-PD-1 Therapy in Head and Neck Cancer, Especially in Hypoxic Environments.

In the tumor microenvironment, wherein cytotoxic lymphocytes interact with cancer cells, lymphocyte exhaustion, an immune checkpoint inhibitor target, is promoted. However, the efficacy of these inhibitors is limited, and improving response rates remains challenging. We previously reported that protein tyrosine phosphatase nonreceptor type (PTPN) 3 is a potential immune checkpoint molecule for activated lymphocytes and that PTPN3 inhibition should be a focus area for cancer immunotherapy development. Therefore, in this study, we focused on PTPN3-suppressive therapy in terms of lymphocyte exhaustion under hypoxic conditions, which are a cancer microenvironment, and investigated measures for improving the response to anti-programmed death receptor (PD)-1 antibody drugs. We found that PTPN3 expression was upregulated in activated lymphocytes under hypoxic conditions, similar to the findings for other immune checkpoint molecules, such as PD-1, T cell immunoglobulin mucin-3, and lymphocyte-activation gene-3; furthermore, it functioned as a lymphocyte exhaustion marker. In addition, PTPN3-suppressed activated lymphocytes promoted the mammalian target of rapamycin (mTOR)-Akt signaling pathway activation and enhanced proliferation, migration, and cytotoxic activities under hypoxic conditions. Furthermore, PTPN3 suppression in activated lymphocytes increased PD-1 expression and enhanced the antitumor effects of anti-PD-1 antibody drugs against head and neck cancer in vitro and in vivo. These results suggest that the suppression of PTPN3 expression in activated lymphocytes enhances the therapeutic effect of anti-PD-1 antibody drugs in head and neck cancer, especially under hypoxic conditions that cause lymphocyte exhaustion.

PTPN3 inhibition contributes to the activation of the dendritic cell function to be a promising new immunotherapy target.

PURPOSE: In a previous study, protein tyrosine phosphatase non-receptor type (PTPN) 3 was identified as an immune checkpoint molecule in lymphocytes, and its potential as a novel target for cancer immunotherapy was anticipated. However, evaluation of dendritic cell (DC) function as antigen-presenting cells is critical for the development of immunotherapy. In this study, we aimed to analyze the biological effect of PTPN3 on DCs induced from human peripheral blood monocytes obtained from healthy individuals. METHODS: We used short-interfering RNA to knock down PTP3 in DCs. For DC maturation, we added cancer cell lysate and tumor necrosis factor-α/interferon-α to immature DCs. In the cytotoxic assay, the target cancer cells were SBC5, unmatched with DCs from healthy human leukocyte antigen (HLA)-A24, or Sq-1, matched with DCs. Enzyme-linked immunosorbent assay was used to determine the amount of cytokines. To examine the intracellular signaling system, intracellular staining was used. RESULTS: PTPN3 knockdown significantly increased the number of DCs, expression of CD80 and chemokine receptor (CCR)7, and production of interleukin-12p40/p70 in mature DCs. In the HLA-A24-restricted DC and human lung squamous cell carcinoma cell cytotoxic assay, inhibition of PTPN3 expression in mature DCs induced cytotoxic T lymphocytes with increased production of INF-γ and granzyme B, and enhanced toxicity against cancer cells and migration to cancer. Furthermore, inhibition of PTPN3 expression activated the mitogen-activated protein kinase pathway in DCs. CONCLUSION: Based on our findings, inhibition of PTPN3 expression could contribute to the development of novel cancer immunotherapies that activate not only lymphocytes but also DCs.

MAML3 Contributes to Induction of Malignant Phenotype of Gallbladder Cancer Through Morphogenesis Signalling Under Hypoxia.

BACKGROUND/AIM: Hedgehog (HH) signalling is a potential therapeutic target for gallbladder cancer (GBC), and Mastermind-like 3 (MAML3) is involved in the transcription of Smoothened (SMO), which is a key protein of HH signalling during hypoxia in the cancer microenvironment. MAML3 is a NOTCH signalling activator, and HH and NOTCH are involved in morphogenesis signalling. However, the association between MAML3-NOTCH and HH signalling and its role in regulating GBC cells remain unknown. This study aimed to determine whether NOTCH signalling affects tumour aggressiveness in GBC under hypoxic conditions and if MAML3 could be a new comprehensive therapeutic target that regulates morphogenesis signalling, HH, and NOTCH in GBC. MATERIALS AND METHODS: We used three cell lines (NOZ, TYGBK1, and TGBC2TKB) and 58 resected specimens. These samples were subjected to cell proliferation, RNA interference, invasion, western blot, and immunohistochemical analyses. RESULTS: MAML3 expression was higher under hypoxic conditions than under normoxic conditions and was involved in the activation of HH and NOTCH signalling. It contributed to the proliferation, migration, and invasion of GBC cells through the NOTCH signalling pathway and enhanced gemcitabine sensitivity. Immunohistochemical analysis showed that MAML3 expression was related to lymphatic invasion, lymph node metastasis, stage category, and a poor prognosis. CONCLUSION: MAML3 contributes to the induction of the malignant phenotype of GBC under hypoxia through the HH and NOTCH signalling pathways and may be a comprehensive therapeutic target of morphogenesis signalling in GBC.

C4orf47 contributes to the dormancy of pancreatic cancer under hypoxic conditions.

In our comprehensive analysis of pancreatic cancer pathology, we found that the C4orf47 molecule was upregulated in hypoxic environments. C4orf47 is reported to be a centrosome-associated protein, but its biological significance in cancer is completely unknown; therefore, we assessed its role in pancreatic cancer. We found that C4orf47 was a direct target of HIF-1α and is upregulated in hypoxic conditions, in which it suppressed the cell cycle and inhibits cell proliferation through up-regulation of the cell cycle repressors Fbxw-7, P27, and p57; and the down-regulation of the cell cycle promoters c-myc, cyclinD1, and cyclinC. Furthermore, C4orf47 induced epithelial-mesenchymal transition and enhanced their cell plasticity and invasiveness. In addition, the p-Erk/p-p38 ratio was significantly enhanced and down-regulated CD44 expression by C4orf47 suppression, suggesting that C4orf47 is involved in pancreatic cancer dormancy under hypoxic conditions. Furthermore, the potential of C4orf47 expression was a good prognostic biomarker for pancreatic cancer. These results contribute to the elucidation of the pathology of refractory pancreatic cancer and the development of novel therapeutic strategies.

PTPN3 Could Βe a Therapeutic Target of Pancreatic Cancer.

BACKGROUND/AIM: Recently, protein tyrosine phosphatase non-receptor type 3 (PTPN3) has gained attention. However, the role of PTPN3 in cancer has not been fully elucidated. In the present study, we analyzed the role of PTPN3 in pancreatic cancer and investigated whether PTPN3 could be a new therapeutic target for pancreatic cancer. MATERIALS AND METHODS: Two pancreatic ductal adenocarcinoma (PDAC) cell lines were used as target cells. Cell proliferation was investigated using cell counting and a xenograft mouse model. Migration and invasion were analyzed using Transwell inserts. Activation-related signaling molecules were examined by western blotting. RESULTS: PTPN3 contributes to the proliferation, migration, and invasion of PDAC cells in vitro. PTPN3 promotes tumor growth in a mouse xenograft model, an action mediated partially through the MAPK pathway. CONCLUSION: PTPN3 could be a new therapeutic target for pancreatic cancer.

Advanced lung adenocarcinoma detected by choroidal metastasis in a patient with amyopathic dermatomyositis: A case report.

A 63-year-old Japanese man with amyopathic dermatomyositis treated with immunosuppressants became aware of distortion of his left visual field, and a metastatic choroidal tumor was suspected. His chest computed tomography (CT) showed a pulmonary nodule in the right upper lobe and mediastinal lymphadenopathy, and he was diagnosed with advanced lung adenocarcinoma with choroidal metastasis. Malignancies associated with dermatomyositis (DM) are often rapidly progressive and, in choroidal metastasis associated with lung cancer, a choroidal lesion is often diagnosed prior to lung cancer; therefore, CT performed at the time of diagnosis of choroidal metastasis may show lung cancer lesions. When ocular symptoms are observed in DM patients, metastatic malignancies should be suspected, and systemic examinations, such as positron emission tomography (PET)-CT, should also be performed.

PTPN3 is a potential target for a new cancer immunotherapy that has a dual effect of T cell activation and direct cancer inhibition in lung neuroendocrine tumor.

In our previous study, we found that inhibition of protein tyrosine phosphatase non-receptor type 3 (PTPN3), which is expressed in lymphocytes, enhances lymphocyte activation, suggesting PTPN3 may act as an immune checkpoint molecule. However, PTPN3 is also expressed in various cancers, and the biological significance of PTPN3 in cancer cells is still not well understood, especially for lung neuroendocrine tumor (NET).Therefore, we analyzed the biological significance of PTPN3 in small cell lung cancer and examined the potential for PTPN3 inhibitory treatment as a cancer treatment approach in lung NET including small cell lung cancer (SCLC) and large cell neuroendocrine cancer (LCNEC). Experiments in a mouse xenograft model using allo lymphocytes showed that PTPN3 inhibition in SCLC cells enhanced the anti-tumor effect of PTPN3-suppressed activated lymphocytes. In addition, PTPN3 was associated with increased vascularization, decreased CD8/FOXP3 ratio and cellular immunosuppression in SCLC clinical specimens. Experiments in a mouse xenograft model using autocrine lymphocytes also showed that PTPN3 inhibition in LCNEC cells augmented the anti-tumor effect of PTPN3-suppressed activated lymphocytes. In vitro experiments showed that PTPN3 is involved in the induction of malignant traits such as proliferation, invasion and migration. Signaling from PTPN3 is mediated by MAPK and PI3K signals via tyrosine kinase phosphorylation through CACNA1G calcium channel. Our results show that PTPN3 suppression is associated with lymphocyte activation and cancer suppression in lung NET. These results suggest that PTPN3 suppression could be a new method of cancer treatment and a major step in the development of new cancer immunotherapies.

GLI2 but not GLI1/GLI3 plays a central role in the induction of malignant phenotype of gallbladder cancer.

We previously reported that Hedgehog (Hh) signal was enhanced in gallbladder cancer (GBC) and was involved in the induction of malignant phenotype of GBC. In recent years, therapeutics that target Hh signaling have focused on molecules downstream of smoothened (SMO). The three transcription factors in the Hh signal pathway, glioma­associated oncogene homolog 1 (GLI1), GLI2, and GLI3, function downstream of SMO, but their biological role in GBC remains unclear. In the present study, the biological significance of GLI1, GLI2, and GLI3 were analyzed with the aim of developing novel treatments for GBC. It was revealed that GLI2, but not GLI1 or GLI3, was involved in the cell cycle­mediated proliferative capacity in GBC and that GLI2, but not GLI1 or GLI3, was involved in the enhanced invasive capacity through epithelial­mesenchymal transition. Further analyses revealed that GLI2 may function in mediating gemcitabine sensitivity and that GLI2 was involved in the promotion of fibrosis in a mouse xenograft model. Immunohistochemical staining of 66 surgically resected GBC tissues revealed that GLI2­high expression patients had fewer numbers of CD3+ and CD8+ tumor­infiltrating lymphocytes (TILs) and increased programmed cell death ligand 1 (PD­L1) expression in cancer cells. These results suggest that GLI2, but not GLI1 or GLI3, is involved in proliferation, invasion, fibrosis, PD­L1 expression, and TILs in GBC and could be a novel therapeutic target. The results of this study provide a significant contribution to the development of a new treatment for refractory GBC, which has few therapeutic options.

NFκB and TGFß contribute to the expression of PTPN3 in activated human lymphocytes.

We previously reported that protein tyrosine phosphatase non-receptor type 3 (PTPN3), which is upregulated in activated lymphocytes, acts as an immune checkpoint. However, the mechanism by which PTPN3 expression is enhanced in activated lymphocytes is unknown. In this study, we analyzed the mechanism of PTPN3 expression in activated lymphocytes with a view for developing a novel immune checkpoint inhibitor that suppresses PTPN3. Through the activation process, lymphocytes showed enhanced NFκB activation as well as increased PTPN3 expression. NFκB enhanced proliferation, migration, and cytotoxicity of lymphocytes. Furthermore, NFκB enhanced PTPN3 expression and tyrosine kinase activation. TGFß reduced PTPN3 expression and NFκB activation in the cancer microenvironment, and suppressed the biological activity of lymphocytes. The results of this study are expected to provide significant implications for improving existing immunotherapy and developing novel immunotherapy.

FAM115C could be a novel tumor suppressor associated with prolonged survival in pancreatic cancer patients.

Hypoxia is a characteristic feature of the tumor microenvironment in pancreatic ductal adenocarcinoma (PDAC). We have recently explored new targeting molecules and pathways in PDAC cells under hypoxic conditions. In this study, we performed a microarray experiment to analyze the genes up-regulated in PDAC cell lines under hypoxia compared to normoxia, and identified human family with sequence similarity 115, member C (FAM115C) as a candidate gene for further study. Our data showed that FAM115C was overexpressed in PDAC cell lines under hypoxia, and FAM115C inhibition promoted PDAC cell migration and invasion in vitro. FAM115C inhibition did not affect tumor cell proliferation in PDAC. Immunohistochemically, FAM115C expression was observed ubiquitously in normal pancreas, pancreatic intraepithelial neoplasia (PanIN) and PDAC tissue, and it was located mainly in the nucleus but also in the cytoplasm of cells. In qPCR analysis, high expression of FAM115C was correlated with better prognosis in patients with PDAC. Our findings suggest that FAM115C could be a novel tumor suppressor associated with prolonged survival in patients with PDAC.

Patched 1-interacting Peptide Represses Fibrosis in Pancreatic Cancer to Augment the Effectiveness of Immunotherapy.

Pancreatic ductal adenocarcinoma (PDAC) is resistant to immunotherapy. As a factor of resistance, the dense fibrosis of this cancer acts as a barrier to inhibit immune cell infiltration into a tumor. We examined the influence of a Hedgehog signal inhibitor, Patched 1-interacting peptide, on fibrosis, infiltration of immune cells, and immunotherapeutic effects on PDAC. We found that this peptide inhibited proliferation and migration of cancer-associated fibroblasts and cancer cells. Furthermore, this peptide reduced the production of extracellular matrix and transforming growth factor ß1 in cancer-associated fibroblasts and induced expression of HLA-ABC in PDAC cells and interferon-γ in lymphocytes. In vivo, the peptide suppressed fibrosis of PDAC and increased immune cell infiltration into tumors. The combination of this peptide and an anti-programmed death-1 antibody augmented the antitumor effect, and this combination showed the same effect in experiments using cancer cells and autologous lymphocytes. These results indicate that, in addition to the direct effect of tumor suppression, the Patched 1-interacting peptide increases the infiltration of immune cells by reducing fibrosis of PDAC and consequently enhances the effect of immunotherapy. Therefore, treatment with this peptide may be a novel therapy with 2 different mechanisms: direct tumor suppression and enhancing the immune response against PDAC.

[Plication for Diaphragmatic Eventration by Complete Video-assisted Thoracoscopic].

A 61-year-old woman was admitted to our hospital with progressive dyspnea on exertion. Chest X-rays and computed tomography (CT) showed elevation of the left diaphragm and atelectasis of the left lung. Eventration of the diaphragm was performed. The redundant diaphragm was plicated with vertical mattress sutures and reinforced by the suturing of the remnant diaphragm to the diaphragm near to the chest wall. During the thoracoscopic procedures, thoracoscopic examination from a small part of the resected diaphragm was conducted simultaneously to ensure safety and avoid damage to intra-abdominal organs. After plication, dyspnea on exertion was resolved and the patient was discharged on the 9th post-operative day.

Successful Surgical Resection following Bronchial Artery Embolization in a Case of Lung Cancer Complicated with Massive Hemoptysis.

Hemoptysis is sometimes observed in lung cancer patients and can be life-threatening. We present a case with severe hemoptysis that was resolved by bronchial artery embolization (BAE) followed by surgery. The presence of necrotic tissue in the majority of the resected tumor and only few cancer cells was presumed to be from loss of bronchial artery blood flow. Although BAE is not a standard therapy for lung cancer, it can be useful and may be considered by physicians as one of the treatment options prior to surgical resection in cases with hemoptysis.

Risk factors for sodium valproate-induced renal tubular dysfunction.

OBJECTIVE: To explore the risk factors for the development of sodium valproate (VPA)-induced renal tubular dysfunction for early diagnosis and treatment. STUDY DESIGN: The subjects were selected from patients who were diagnosed with epilepsy and administered VPA. Blood and spot urine samples were collected and measured the concentration of VPA, the level of serum phosphorus, serum uric acid, serum free carnitine, serum cystatin-c, and urine ß2-microglobulin (BMG). Patients with urine BMG/creatinine levels above 219.2 were treated as renal proximal tubular dysfunction (RTD), with all others treated as non-RTD. RESULTS: Eighty-seven patients, 4-48 years, 53 men and 34 women, were studied. RTD group is 17 patients and non-RTD group is 70 patients. Univariate analyses revealed that the RTD patients were more likely to be bedridden, receiving enteral tube feeding, taking more anticonvulsants, and demonstrating significantly lower serum levels of free carnitine, uric acid, and phosphorus. Among them, bedridden, free serum carnitine, and phosphorus levels were associated with the development of RTD by multivariate analysis. CONCLUSIONS: Bedridden patients receiving VPA are susceptible to hypocarnitinemia, which can cause RTD and may lead to FS. Therefore, urinary BMG should be measured regularly in all patients receiving VPA to assess renal tubular function. An additional measurement of serum free carnitine level should be considered in patients who developed RTD. Supplementation of carnitine for those patients to prevent such complication deserves for further study.

Eosinophilic funiculitis initially diagnosed as irreducible inguinal hernia: A case report.

BACKGROUND: Most groin masses are first suspected to be groin hernias. More than 80% of bulging groin lesions are reportedly diagnosed as hernias by ultrasonography. Establishment of the correct diagnosis of hernia among all differential diagnoses is not easy. We herein describe a very rare case of groin eosinophilic funiculitis that presented as an irreducible groin hernia. CASE PRESENTATION: A 59-year-old man presented to our hospital with suspicion of a right groin hernia. He had a 1-week history of a painful right groin tumor. The tumor was about 4 cm without skin redness or warmth, irreducible even in the supine position, and associated with mild tenderness. Enhanced computed tomography showed that the mass seemed to be connected to the intra-abdominal structures. With time, the patient's pain did not increase, the inflammatory response did not worsen, and no ischemic signs were observed by enhanced computed tomography. Therefore, we diagnosed the tumor as an irreducible but not incarcerated hernia and performed elective surgery. Intraoperative examination revealed no hernia sac, and a 4-×3-cm tumor was observed around the spermatic cord. A malignant tumor was not completely ruled out. High orchiectomy was performed after consultation with the urologists. Pathological examination of the tumor showed no malignant features, and the final diagnosis was eosinophilic funiculitis with massive inflammatory changes and eosinophil invasion. CONCLUSION: Eosinophilic funiculitis is very rare; only three cases have been reported to date. We should always consider unusual causes of groin masses during a surgical approach to hernia-like lesions.

The vitamin E derivative, EPC-K1, suppresses inflammation during hepatic ischemia-reperfusion injury and exerts hepatoprotective effects in rats.

BACKGROUND: An important component of postoperative management includes alleviation of hepatic ischemia-reperfusion (I/R) injury, which commonly results from liver surgery. EPC-K1 is a hydroxyl radical scavenger reported to have mitigating effects on I/R injury in many organs. This study evaluates the effects of EPC-K1 on hepatic I/R injury. MATERIALS AND METHODS: Rats were injected subcutaneously with either EPC-K1 (100 mg/kg) or saline. The hepatic artery and left branch of the portal vein were clamped for 45 min under general anesthesia. Indicators of liver function, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH), and of liver tissue damage were evaluated after 6h and 24h of reperfusion. Serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and high-mobility group box 1 (HMGB1) protein were measured, and apoptosis was quantified via caspase 3/7 activity and TUNEL assay. RESULTS: AST, ALT, and LDH levels increased significantly as a result of hepatic I/R injury, but were attenuated by EPC-K1 administration. Histologic findings revealed that normal structure of the hepatic parenchyma was maintained in rats pretreated with EPC-K1. TNF-α, IL-6, and HMGB1 levels rose significantly after reperfusion, together with activation of the inflammatory response. However, EPC-K1 administration suppressed levels of inflammatory markers and attenuated the inflammatory response. Moreover, EPC-K1 administration prevented apoptosis as determined by inhibition of caspase 3/7 activity and a decrease in apoptotic cells. CONCLUSIONS: Results demonstrate that EPC-K1 inhibits the inflammatory response and suppresses apoptosis during hepatic I/R injury. This suggests that EPC-K1 has hepatoprotective effects, and may be a valuable and novel therapeutic agent in the clinical setting.

A translocator protein ligand PK11195 shows antigrowth activity in human choriocarcinoma cells.

The potential anticancer agent 1-(2-chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195), a translocator protein ligand (initially described as a ligand for the peripheral benzodiazepine receptor), induces apoptosis in some lines of human tumor cells. We investigated the effect of PK11195 in the choriocarcinoma cell line, BeWo. BeWo cells were treated with various concentrations of PK11195, and changes in cell growth, the cell cycle, apoptosis, and related parameters were examined. A WST-1 assay showed that BeWo cells were sensitive to the growth inhibitory effect of PK11195. In contrast, the nonsite selective ligand diazepam has a little effect on these cells. Cell cycle analysis indicated that exposure to PK11195 decreased the proportion of cells in the S phase and increased the proportion in the G0/G1 phases of the cell cycle. Induction of apoptosis was confirmed by Annexin V staining of externalized phosphatidylserine, by the loss of mitochondrial transmembrane potential, and by antibodies directed against histones from fragmented DNA. This induction occurred in conjunction with the altered expression of genes related to cell growth, malignant phenotype, and apoptosis. These results suggest that PK11195 may serve as a therapeutic agent for the treatment of choriocarcinoma.

Calcium/calmodulin-dependent kinase inhibitor induces growth inhibition, cell cycle arrest, and apoptosis in human choriocarcinoma cells.

KN-93, a membrane-permeant calcium/calmodulin- dependent kinase-selective inhibitor, induces apoptosis in some lines of human tumor cells. We investigated the effect of KN-93 in the choriocarcinoma cell line, BeWo. BeWo cells were treated with various concentrations of KN-93, and changes in cell growth, the cell cycle, apoptosis, and related parameters were examined. A WST-1 assay showed that BeWo cells were sensitive to the growth inhibitory effect of KN-93. Cell cycle analysis indicated that exposure to KN-93 decreased the proportion of cells in the S phase and increased the proportion in the G0/G1 phases of the cell cycle. Induction of apoptosis was confirmed by Annexin V staining of externalized phosphatidylserine, by the loss of mitochondrial transmembrane potential, and by antibodies directed against histones from fragmented DNA. This induction occurred in conjunction with the altered expression of genes related to cell growth, malignant phenotype, and apoptosis. These results suggest that KN-93 may serve as a therapeutic agent for the treatment of choriocarcinoma.

[Control of postoperative nausea and vomiting by preventive administration of dexamethasone].

BACKGROUND: Postoperative nausea and vomiting (PONV) are the most frequent side effects after anesthesia. Patients with persistent PONV continue to be impaired in performing their normal daily activities. We studied the controlling effect of dexamethasone (4 mg) before the induction of general anesthesia in the prevention of PONV. METHODS: Ninety-one patients were divided into respiratory surgery group (dexamethasone N=22, none N=23) and gynecology group (dexamethasone N=22, none N=24), respectively. Dexamethasone group received dexamethasone 4 mg before the induction of general anesthesia. PONV and antiemetic requirements were recorded. RESULTS: In the dexamethasone group (respiratory surgery, gynecology), the incidences of PONV during the initial 24 hour postoperative period were 36.4% (N=8), and 18.2% (N=4), respectively. In the none group, the incidences were 43.5% (N=10), and 41.7% (N=10), respectively Antiemetic requirements were 22.7% (N=5), 9.1% (N=2), 39.1% (N=9), and 20.1% (N=5), respectively (NS). In gynecology group, in almost all the patients droperidol was used in epidural anesthesia. Combination of dexamethasone and droperidol may have greater antiemetic action than a single drug. CONCLUSIONS: Combination therapy with dexamethasone and droperidol may reduce PONV in patients undergoing surgery.