Tumour-infiltrating CD8 to FOXP3 lymphocyte ratio in predicting treatment responses to neoadjuvant chemotherapy of aggressive breast cancer.

BACKGROUND: Tumour-infiltrating lymphocytes (TILs) can be used to monitor the immune response, and are important in predicting treatment responses and outcomes for various types of cancer. Recently, specific TIL subsets have been reported to be clinically useful in predicting treatment responses. The CD8+/FOXP3+ TIL ratio (CFR) may be a more sensitive indicator for monitoring immune function. This study investigated the clinical significance and value of CFR as a biomarker to predict treatment responses to neoadjuvant chemotherapy for breast cancer. METHODS: Patients with resectable early-stage breast cancer treated with neoadjuvant chemotherapy at Osaka City University Hospital, Japan, between 2007 and 2013 were included. Oestrogen receptor, progesterone receptor, human epidermal growth factor receptor (HER) 2, Ki-67, CD8 and FOXP3 status were assessed by immunohistochemistry, and correlated with pathological complete response (pCR). RESULTS: A total of 177 patients were included, of whom 90 had a high CFR and 87 a low CFR. Triple-negative breast cancer (TNBC) was more common in the high-CFR group than in the low-CFR group (46 versus 23 per cent; P = 0·002), as was HER2-enriched breast cancer (HER2BC) (27 versus 14 per cent; P = 0·033). Among these patients, the pCR rate was significantly higher in the high-CFR group than in the low-CFR group (TNBC: P = 0·022; HER2BC: P < 0·001). In multivariable analysis high-CFR status was an independent predictor of a favourable prognosis: hazard ratio 0·24 (95 per cent c.i. 0·05 to 0·72; P = 0·015) for TNBC and 0·10 (0·10 to 0·90; P = 0·041) for HER2BC. CONCLUSION: The CFR may be a useful biomarker to predict treatment response to neoadjuvant therapy in aggressive breast cancer subtypes, such as TNBC and HER2BC.

Disseminated Hormographiella aspergillata infection with involvement of the lung, brain, and small intestine following allogeneic hematopoietic stem cell transplantation: case report and literature review.

Disseminated infection by Hormographiella aspergillata is extremely rare and small intestine involvement has not been reported previously. A 51-year-old man with myelodysplastic syndrome developed pneumonia after cord blood cell transplantation. Fungal growth from the biopsied lung was identified as H. aspergillata by morphology and the gene analysis. Although antifungal agents including voriconazole and liposomal amphotericin B were administered, he died of disseminated H. aspergillata infection. We review the literature and discuss the treatment and prognosis.

Olanzapine increases hepatic glucose production through the activation of hypothalamic adenosine 5'-monophosphate-activated protein kinase.

AIMS: To investigate the mechanism of the metabolic disturbance induced by the atypical antipsychotic olanzapine, we examined whether adenosine 5'-monophosphate-activated protein kinase (AMPK) in the hypothalamus and hepatic glucose production are involved in the effect of olanzapine. METHODS: Male 6-week-old ICR mice were used. Blood glucose levels were determined by the glucose oxidase method. The mRNA levels of gluconeogenic or glycolytic enzymes were measured by reverse transcription polymerase chain reaction (RT-PCR). AMPK expression was measured by Western blotting. RESULTS: Systemic injection of olanzapine increased blood glucose levels in both unfasted and fasted mice. However, the increase in fasted mice was less than that in unfasted mice. Central administration of olanzapine also increased the blood glucose levels in unfasted mice, but not in fasted mice. In a pyruvate tolerance test, olanzapine significantly increased blood glucose levels. In addition, olanzapine increased the mRNA levels of glucose-6-phosphatase (G6Pase), a gluconeogenic enzyme, in the liver. Furthermore, olanzapine increased phosphorylated AMPK in the hypothalamus of unfasted mice, and olanzapine-induced hyperglycaemia was inhibited by the AMPK inhibitor compound C. Central administration of the AMPK activator AICAR significantly increased G6Pase mRNA levels in the liver and blood glucose levels. Moreover, both olanzapine- and AICAR-induced hyperglycaemia were attenuated by the ß-adrenergic receptor antagonist propranolol, suggesting that olanzapine and AICAR induce hepatic glucose production through the sympathetic nervous system. CONCLUSIONS: Our results indicate that olanzapine activates AMPK in the hypothalamus, which increases hepatic glucose production via the sympathetic nervous system.

Spontaneously complete regression of pseudolymphoma of the remnant pancreas after pancreaticoduodenectomy.

BACKGROUND: Pancreatic pseudolymphoma is extremely rare. METHOD: We present multiple pseudolymphomas in the head and body of the pancreas. The hypoechoic lesions observed by endoscopic ultrasound were enhanced in late-phase angio-computed tomography and homogeneously hypointensive in T1-weighted magnetic resonance imaging (MRI). (18)F-fluorodeoxyglucose positron emission tomography showed strong accumulation in the lesions. The lesions were suspected to be non-functioning islet cell carcinoma. The intraoperative pathological diagnosis for the specimen obtained by a pylorus-preserving pancreaticoduodenectomy was non-neoplastic lymphoid cells. The remnant lesion in the pancreatic body was preserved. RESULTS: Macroscopically, the mass was well-circumscribed gray-white colored lesion. The pathological diagnosis was pancreatic pseudolymphoma. The lesion in the remnant pancreas spontaneously disappeared within one year after the operation. CONCLUSION: The differential diagnosis of pancreatic pseudolymphoma from malignant tumor is very difficult, however, the image findings demonstrated here may be informative. The spontaneous disappearance of pancreatic pseudolymphoma was firstly observed in the present case.

Fatal BK virus pneumonia following stem cell transplantation.

We report the case of a 39-year-old male patient who died of severe BK virus (BKV) pneumonia 168 days after hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia. After suffering from BKV-associated late-onset hemorrhagic cystitis (HC) with long-term sustained BKV viremia, he died of rapidly progressive pneumonia. On autopsy, numerous viral intranuclear inclusions were seen in his lungs and bladder. An immunohistochemical examination of his lungs was positive for simian virus 40. Based on these pathological results and the high sustained BKV viral load in his blood, we reached a diagnosis of BKV pneumonia. Viral infection can occasionally become life threatening among HSCT recipients. It is widely known that BKV can cause late-onset HC, but BKV-associated pneumonia is rare. Because of its rapid progression and poor prognosis, it is difficult to make an antemortem diagnosis of BKV pneumonia. A treatment strategy for BKV pneumonia also needs to be formulated. Similar to other viral pathogens, BKV can cause pneumonia and the clinician should therefore be aware of it in immunocompromised patients.

Correction to: Circulating tumor cell clusters-associated gene plakoglobin is a significant prognostic predictor in patients with breast cancer.

[This corrects the article DOI: 10.1186/s40364-017-0099-2.].

[Valve-in-valve replacement of primary tissue valve failure of bovine pericardial valve minor].

A 73-year-old woman who underwent mitral valve replacement with a 31 mm Carpentier Edwards Pericardial Xenograft 19 years ago. She revealed sudden onset of a grade IV/VI a seagull like diastolic murmur at the apex, and severe hematuria. Echocardiography demonstrated severe mitral regurgitation. These findings were consistent with acute primary tissue valve failure. Therefore we performed emergency reoperation. At operation, valve leaflet was torn at the commissural stitch, and bioprosthesis strut was buried in the left posterior ventricular wall. The mitral prosthetic valve replaced with a 25 mm CarboMedics OptiForm using a technique of valve-in-valve replacement. This procedure would be one option for replacement of bioprosthetic mitral valve.

Formation of vitamin D-binding protein-actin and binary and ternary plasma gelsolin-actin complexes in human serum.

After the addition of actin to serum, the binding of actin to serum actin-binding proteins was analyzed by the method of immunoblotting using monospecific antibodies against vitamin D-binding protein (DBP) (group-specific component, Gc), human skeletal actin and human plasma gelsolin. When increasing amounts of globular actin were added to serum, actin bound to DBP preferentially. After exhausting DBP, actin began to bind to plasma gelsolin. When equally increasing amounts of filamentous actin were added to serum, actin was bound to both plasma gelsolin and DBP, and then uncomplexed DBP removed one actin molecule from gelsolin-actin 1:2 complex, resulting in a gelsolin-actin 1:1 complex. These results support the theory that the actin-depolymerizing activity of serum is due to the concerted role of plasma gelsolin and DBP.

Energization of amino acid transport in energy-depleted Ehrlich cells and plasma membrane vesicles.

We redirect attention to contributions to the energization, of the active transport of amino acids in the Ehrlich cell, beyond the known energization, by down-gradient comigration of Na+, beyond possible direct energization by coupling to ATP breakdown, and beyond known energization by exchange with prior accumulations of amino acids. We re-emphasize the uphill operation of System L, and by prior depletion of cellular amino acids show that this system must receive energy beyond that made available by their coupled exodus. After this depletion the Na+-indepdendent accumulation of the norbornane amino acid, 2-aminobicycloheptane-2-carboxylic acid becomes strongly subject to stimulation by incubation with glucose. Energy transfer between Systems A and L through the mutual substrate action of ordinary amino acids was minimized although not entirely avoided by the use of amino acid analogs specific to each system. When 2,4-dinitrophenol was included in the depleting treatment, and pyruvate, phenazine methosulfate, or glucose used for restoration, recovery of uptake of the norbornane amino acid was independent of external Na+ or K+ levels. Restoration or the uptake of 2-(methylamino)isobutyric acid was, however, decreased by omission of external K+. Contrary to an earlier finding, restoration of uptake of each of these amino acids was associated with distinct and usually correlated rises in cellular ATP levels. ATP addition failed to stimulate exodus of the norbornane amino acid from plasma membrane vesicles, although either NADH or phenazine methosulfate did stimulate exodus. ATP production and use is thus associated with transport energization although evidence for a direct role failed to appear.

Novel responses of ZRF, a variant of human MTF-1, to in vivo treatment with heavy metals.

Heavy metal-dependent transcriptional activation of metallothionein (MT) genes is mediated by multiple enhancer sequences, metal responsive element (MRE), located in the upstream region of the genes. Previously, we have reported purification of a zinc-dependent MRE-binding protein, zinc regulatory factor (ZRF), from HeLa cells, and have pointed to the close relationship between ZRF and mouse MRE-binding transcription factor-1 (MTF-1) according to the analysis of partial amino acid sequences. By means of cDNA cloning and the product analyses, we show that ZRF is a variant of human MTF-1 (hMTF-1), which carries a single amino acid exchange in the zinc finger domain. Accordingly, ZRF is renamed hMTF-1b. Expression of hMTF-1b in HeLa cells is constitutive at both mRNA and protein levels, and is unaffected by treatment with cadmium (Cd). On the other hand, when cells were fractionated into nuclear extract and cytosol, a large part of the hMTF-1b was recovered in the cytosol fraction. A significant increase in the amount of nuclear hMTF-1b occurs when cells are treated with various heavy metals, including Cd, Zn, Cu and Ag, which is associated with concomitant decrease in the amount recovered in the cytosol fraction. Since immunocytochemical analysis revealed that intracellular distribution of hMTF-1b is restricted to the nucleus irrespective of the heavy metal treatment, such an increment in the nuclear extracts apparently results from promotion of nuclear retention of hMTF-1b by the heavy metal treatment. Analysis by native gel electrophoresis shows that the mobility of hMTF-1b significantly changes in association with Cd treatment, raising the possibility that a conformational change of hMTF-1b occurs in response to treatment with heavy metals in vivo.

1alpha,25-dihydroxyvitamin D(3) and its potent synthetic analogs downregulate tissue factor and upregulate thrombomodulin expression in monocytic cells, counteracting the effects of tumor necrosis factor and oxidized LDL.

BACKGROUND: We have recently found that a hormonally active form of vitamin D, 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], exerts anticoagulant effects by upregulating the expression of an anticoagulant glycoprotein, thrombomodulin (TM), and downregulating the expression of a critical coagulation factor, tissue factor (TF), in monocytic cells including human peripheral monocytes. In this study, we investigated the counteracting effects of 1,25(OH)(2)D(3) and its potent analogs on TF induction and TM downregulation by tumor necrosis factor and oxidized LDL in monocytic cells and the modulatory effects of potent analogs on TF and TM expression. METHODS AND RESULTS: Effects of 1,25(OH)(2)D(3) and its potent synthetic analogs (22R)-22-methyl-20-epi-1,25(OH)(2)D(3) (KY3) and 22-oxacalcitriol on TF and TM antigen levels, cell surface activities, and mRNA levels in monocytic cells were examined. 1, 25(OH)(2)D(3) and its potent analogs showed anticoagulant effects in monocytic cells by downregulating TF and upregulating TM expression, counteracting the effects of tumor necrosis factor and oxidized LDL. KY3 was most potent in its regulatory effect on TF and TM expression. CONCLUSIONS: Because KY3 has the highest affinity for vitamin D receptor, our findings suggest that TF and TM regulation by 1, 25(OH)(2)D(3) analogs is also mediated by vitamin D receptor. The 1, 25(OH)(2)D(3) analogs KY3 and 22-oxacalcitriol may have the potential to serve as an agent for preventing and treating atherosclerotic and other cytokine-mediated thrombotic diseases and as a tool for studying the molecular mechanisms of TF and TM regulation.

Appearance of a different clone of Epstein-Barr virus genome in recurrent tumor of pyothorax-associated lymphoma (PAL) and a mini-review of PAL.

A case of pyothorax-associated lymphoma (PAL) is reported. A 76-year-old Japanese man developed a lymphoma in the pleural cavity after 46 years duration of pyothorax due to pulmonary tuberculosis. The histologic diagnosis of biopsy specimen was diffuse large cell lymphoma of B cell type. The lymphoma cells contained the monoclonal Epstein-Barr virus (EBV) determined by the analysis of terminal repeat of EBV genome and expressed EBV nuclear antigen 2 and latent membrane protein 1 (LMP1). He received antineoplastic chemotherapy and was induced to complete remission (CR). After 19 months of CR, the lymphoma developed again in the thoracic wall. Histopathology and immunohistochemical phenotypes of recurrent tumor were almost the same as those of the primary tumor with the exception of a little more frequent expression of LMP1. The EBV genome in lymphoma cells was monoclonal, however, the clone was different from that of the primary tumor. After antineoplastic chemotherapy, minor EBV-positive clones in primary lymphoma might survive and develop into recurrent tumor. These results suggest that the PAL starts as poly- or oligoclonal proliferation of B lineage cells. This poly- or oligoclonality of PAL at the initial stage may suggest underlying immunosuppressive conditions in the development of PAL.

The long-term effect of menopause on postmenopausal bone loss in Japanese women: results from a prospective study.

The aim of this study was to elucidate perimenopausal bone loss in relation to menstrual conditions and to investigate the long-term effect of menopause on bone loss in aged women. The rate of change in bone mineral density (BMD) was measured twice at an exact interval of 12 months by dual-energy X-ray absorptiometry (DXA) at the lumbar spine in 176 pre- and postmenopausal healthy women 41-65 years of age. Serum follicle-stimulating hormone, intact and N-fragment osteocalcin (OC), three types of vitamin D3, parathyroid hormone (PTH), and calcitonin were also determined. Women who exercised regularly or had anatomical changes at the lumbar spine were excluded from this study. The subjects were divided into eight groups based on their menstrual status and years since menopause. Annual bone loss at the lumbar spine of premenopausal women with regular menstruation was -0.2+/-1.9% (95% confidence interval, -0.9 approximately -0.4%) and was not statistically different from zero, while that of women with irregular menstruation or at menopausal transition was -2.1+/-3.4% (-3.4 approximately -0.8%), and -3.3+/-2.3% (-5.2 approximately -0.3%), respectively, and was significantly different from zero. Serum OC levels of women at menopausal transition were significantly higher than those of women with regular menstruation, suggesting that bone loss had commenced in these women. The rate of annual change in BMD of women who were menopausal for 1-3, 4-6, 10-12, and more than 13 years was -3.1+/-4.0% (-4.7 approximately -1.5%), -1.2+/-2.6% (-2.2 approximately -0.2%), -1.0+/-3.0% (-2.3 approximately -0.3%), and -2.3+/-2.1% (-3.7 approximately -1.0%), respectively, and was significantly less than zero. But the annual bone loss of women who were menopausal for 7-9 years was -1.5+/-2.6% (-3.0 approximately -0.1%) and was not statistically significant from zero. These results indicate that postmenopausal women lose BMD in two phases. The early bone loss is rapid and commences during irregular menstruation, then is attenuated within 6 years after the onset of menopause. The second bone loss commences after the attenuation of the first bone loss. Among bone metabolic hormones, intact PTH alone showed an age-related increase and was suggested as being a causal factor of bone loss in women who were menopausal for 13 years or more.

Pretreatment with protein kinase C activator phorbol 12,13-dibutyrate attenuates the antinociception induced by mu- but not epsilon-opioid receptor agonist in the mouse.

The effects of pretreatment with a protein kinase C activator, phorbol 12,13-dibutyrate, on antinociception induced by i.c.v.-administered mu-opioid receptor agonist (D-Ala2, NMePhe4, Gly(ol)5) enkephalin (DAMGO) or morphine and epsilon-opioid receptor agonist beta-endorphin were studied in male ICR mice. The tail-flick responses were used for antinociceptive tests. I.c.v. pretreatment with phorbol 12,13-dibutyrate (50 pmol) for 30 or 60 but not 10 min attenuated antinociception induced by i.c.v.-administered DAMGO. I.c.v. pretreatment with phorbol 12,13-dibutyrate (10 and 50 pmol) for 60 min caused a dose-dependent attenuation of DAMGO (19.5 pmol)- or morphine (6.0 nmol)-induced antinociception. The dose-response curve for DAMGO-induced antinociception was shifted to the right by 7.3-fold by i.c.v. pretreatment with phorbol 12,13-dibutyrate (50 pmol) for 60 min. However, the i.c.v.-administered beta-endorphin-induced antinociception was not affected by the same pretreatment with phorbol 12,13-dibutyrate. The attenuation of i.c.v.-administered DAMGO- and morphine-induced antinociception by phorbol 12,13-dibutyrate was reversed by concomitant i.c.v. pretreatment with a selective protein kinase C inhibitor calphostin C. These results suggest that activation of protein kinase C by phorbol 12,13-dibutyrate leads to the desensitization of mu-, but not epsilon-opioid receptor-mediated antinociception. These findings also provide additional evidence for differential intracellular modulation on antinociceptive action of mu- and epsilon-opioid receptor agonists.

Role of the phosphatidylinositol-specific phospholipase C pathway in delta-opioid receptor-mediated antinociception in the mouse spinal cord.

Stimulation of delta-opioid receptors has been shown to activate phospholipase C via the activation of G-proteins in vitro. The present study was designed to determine, with the tail-flick method, whether the stimulatory effect of delta-opioid receptor agonists on phospholipase C and inositol lipid turnover participates in the mechanisms of the delta-opioid receptor-mediated antinociception in the mouse spinal cord. Intrathecal pretreatment with the phospholipase C inhibitors neomycin and U73122, which produced no changes in the basal tail-flick latencies when they were injected alone, significantly attenuated the antinociception induced by intrathecal administration of the selective delta-opioid receptor agonist [D-Ala(2)]deltorphin II in mice. The selective phosphatidylinositol-specific phospholipase C inhibitor ET-18-OCH(3) inhibited the antinociception induced by intrathecal administration of [D-Ala(2)]deltorphin II in a dose-dependent manner. In mice undergoing treatment with LiCl, which impairs phosphatidylinositol synthesis, the antinociception induced by intrathecal administration of [D-Ala(2)]deltorphin II was significantly reduced. Co-administration of D-myo-inositol-1,4,5-trisphosphate restored the [D-Ala(2)]deltorphin II-induced antinociception in LiCl-pretreated mice. On the other hand, intrathecal pretreatment with the selective protein kinase C inhibitor calphostin C, but not the protein kinase A inhibitor KT5720, resulted in a dose-dependent enhancement of the [D-Ala(2)]deltorphin II-induced antinociception. These results indicate a potential role for the phospholipase C-inositol-1,4, 5-trisphosphate pathway in the expression of delta-opioid receptor-mediated antinociception in the mouse spinal cord. Furthermore, activation of protein kinase C by the stimulation of delta-opioid receptors may constitute a significant pathway involved in negative modulation of spinal delta-opioid receptor-mediated antinociception.

The role of lipopolysaccharide injected systemically in the reactivation of collagen-induced arthritis in mice.

1. We investigated the role of bacterial lipopolysaccharide (LPS) in the reactivation of autoimmune disease by using collagen-induced arthritis (CIA) in mice in which autoimmunity to the joint cartilage component type II collagen (CII) was involved. 2. CIA was induced by immunization with CII emulsified with complete Freund's adjuvant at the base of the tail (day 0) followed by a booster injection on day 21. Varying doses of LPS from E. coli were i.p. injected on day 50. 3. Arthritis began to develop on day 25 after immunization with CII and reached a peak on day 35. Thereafter, arthritis subsided gradually but moderate joint inflammation was still observed on day 50. An i.p. injection of LPS on day 50 markedly reactivated arthritis on a dose-related fashion. Histologically, on day 55, there were marked oedema of synovium which had proliferated by the day of LPS injection, new formation of fibrin, and intense infiltration of neutrophils accompanied with a large number of mononuclear cells. The reactivation of CIA by LPS was associated with increases in anti-CII IgG and IgG2a antibodies as well as various cytokines including IL-12, IFN-gamma, IL-1beta, and TNF-alpha. LPS from S. enteritidis, S. typhimurium, and K. neumoniae and its component, lipid A from E. coli also reactivated the disease. Polymyxin B sulphate suppressed LPS- or lipid A-induced reactivation of CIA. 4. These results suggest that LPS may play an important role in the reactivation of autoimmune joint inflammatory diseases such as rheumatoid arthritis in humans.

Activation of the beta-catenin gene by interstitial deletions involving exon 3 as an early event in colorectal tumorigenesis.

beta-Catenin has been identified as an oncogene in several tumors including colorectal cancers. beta-Catenin gene is activated by interstitial deletions involving exon 3 in colorectal carcinomas of Japanese population, in contrast to amino acid substitutions detected among Caucasian population. The aim of this study was to examine the type and frequency of beta-catenin gene mutation during early stages of colorectal tumorigenesis. We screened 100 colorectal adenomas for somatic mutations in the beta-catenin gene by single-strand conformation polymorphism method, as well as polymerase chain reaction amplification. In cases with mutations, sequencing analyses and immunohistochemical staining were also performed. Somatic interstitial deletions of 272-413 bp, each of which included all parts of exon 3, were detected in three tumors. However, no adenoma carried missense mutations. We confirmed accumulation of aberrant beta-catenin protein in cytoplasm and nuclei of adenoma cells by immunohistochemical analysis. Our results suggested that activation of the beta-catenin gene by interstitial deletions involving exon 3 might be less frequent compared with frequent alterations of adenomatous polyposis coli (APC) gene, but could be an early event in colorectal tumorigenesis equivalent to APC gene alterations in the Japanese population.

Effects of bilateral transvenous diaphragm pacing on hemodynamic function in patients after cardiac operations. Experimental and clinical study.

The effects of bilateral transvenous diaphragm pacing and intermittent positive-pressure ventilation on hemodynamic function were compared by animal experiment in 18 dogs and by clinical study in 14 patients during the postoperative period after cardiac operations. Aortic, pulmonary arterial, right atrial, and left atrial pressures (transmural) and aortic flow were increased by diaphragm pacing in the canine experiment. In dogs with induced tricuspid insufficiency, aortic pressure, right and left atrial pressures, and aortic blood flow increased, similar to the results obtained in the clinical study. Diaphragm pacing produced a sufficient tidal volume (7.2 to 12 ml/kg) for maintenance of normal blood gas levels in the patients, all of whom recovered spontaneous breathing without any weaning problems after 2 to 6 hours of diaphragm pacing. The catheter electrode used for stimulation was placed 30 mm away from the sinus node to avoid arrhythmias. Respiratory control by diaphragm pacing is hemodynamically superior to that by intermittent positive-pressure ventilation, and its efficacy is expected, especially in critical cases or in diseases or conditions in which the decrease in the load of the right heart affects the hemodynamic status of the patient.

Epstein-Barr virus in malignancies in renal transplant recipients in Japan.

A role for Epstein-Barr virus (EBV) in the development of malignancies including lymphomas, and carcinoma of the stomach, nasopharynx, thymus and salivary gland is suggested. It is indicated that EBV evokes polyclonal-B-cell-proliferative diseases in immunocompromised hosts, such as transplant patients, which results in monoclonal malignant lymphomas. The suppression of immune functions in these patients is thought to lead to incomplete elimination of the cells expressing EBV latent infection genes. To examine the etiological role of EBV in the development of malignancies following renal transplant in Japan, 42 malignancies in 1744 cases of renal transplant were studied for the presence and type of EBV. The polymerase chain reaction revealed that 5 malignancies were positive for EBV, all type A: 2 of 2 cases of non-Hodgkin's lymphoma (NHL), 2 of 8 cases of gastric adenocarcinoma of the common type, and 1 of 2 cases of gastric plasmacytoma. In situ hybridization revealed positive signals in the nucleus of tumor cells in 2 cases of NHL and 1 of plasmacytoma. Positive signals were found in the small lymphoid cells but not in the tumor cells in 2 cases of gastric carcinoma. On the basis of these findings, a role for EBV in the development of malignancies in renal transplant patients is unlikely except for lymphoid neoplasias.