Histone methyltransferase DOT1L coordinates AR and MYC stability in prostate cancer.

The histone methyltransferase DOT1L methylates lysine 79 (K79) on histone H3 and is involved in Mixed Lineage Leukemia (MLL) fusion leukemogenesis; however, its role in prostate cancer (PCa) is undefined. Here we show that DOT1L is overexpressed in PCa and is associated with poor outcome. Genetic and chemical inhibition of DOT1L selectively impaired the viability of androgen receptor (AR)-positive PCa cells and organoids, including castration-resistant and enzalutamide-resistant cells. The sensitivity of AR-positive cells is due to a distal K79 methylation-marked enhancer in the MYC gene bound by AR and DOT1L not present in AR-negative cells. DOT1L inhibition leads to reduced MYC expression and upregulation of MYC-regulated E3 ubiquitin ligases HECTD4 and MYCBP2, which promote AR and MYC degradation. This leads to further repression of MYC in a negative feed forward manner. Thus DOT1L selectively regulates the tumorigenicity of AR-positive prostate cancer cells and is a promising therapeutic target for PCa.

RT-PCR suggests human skeletal muscle origin of alveolar soft-part sarcoma.

In 1952, Christopherson et al. proposed that alveolar soft-part sarcoma (ASPS) was a distinct entity with unique clinical and pathological features. Since their report, its histogenesis has not been determined. In order to clarify the histogenesis of ASPS, a study using reverse transcription polymerase chain reaction using cDNAs from MyoD1 and myogenin, and the actin filament from human-skeletal-muscle-related mRNAs has been performed in 5 cases of ASPS. The expression of MyoD1 and myogenin was determined in 5 and 2 cases of the 5 cases, respectively. Moreover, expression of the many mRNAs from the actin filament of skeletal muscle was also found in ASPS. According to these findings, it is now postulated that ASPS is of skeletal muscle origin.

Detection of urinary macrophages expressing the CD16 (Fc gamma RIII) molecule: a novel marker of acute inflammatory glomerular injury.

BACKGROUND: The CD16 antigen is the Fc gamma receptor III. CD14+CD16+ cells are proinflammatory monocytes/macrophages (Mo/M phi) that constitute a minor population in the peripheral blood of healthy individuals. Little is known about the expression of CD16 antigen on Mo/M phi in glomerulonephritis. METHODS: Flow cytometric analyses were performed on urine and blood samples obtained from 209 patients with various renal diseases. Patients variously suffered from rapidly progressive crescentic glomerulonephritis (RPGN), membranoproliferative glomerulonephritis (MPGN), postinfectious acute glomerulonephritis (AGN), Henoch-Schönlein purpura nephritis (HSPN), IgA nephropathy (IgAN), membranous nephropathy (MN), minimal change nephrotic syndrome (MCNS), lupus nephritis (LN), acute interstitial nephritis, hereditary nephropathy, idiopathic renal hematuria (IRH), and renal stone. RESULTS: The CD16+ M phi population of cells was present in the urine of hematuria-positive patients with proliferative glomerulonephritis, including AGN, IgAN, RPGN, MPGN, and LN with acute inflammatory lesions, such as endocapillary proliferation, tuft necrosis, and cellular crescents. In contrast, the urinary CD16+ M phi population was negligible in hematuria-positive patients with nonproliferative renal disease, including hereditary nephropathy, IRH, and renal stone and also in patients with proliferative glomerulonephritis lacking acute inflammatory lesions. Total urinary M phi of these patients were much less than those of patients having proliferative glomerulonephritis with acute inflammatory lesions. Transient expansion of the CD16+ M phi population in urine was observed during the acute exacerbation of urinary abnormalities, whereas the disappearance of CD16+ M phi closely preceded the amelioration of urinary abnormalities in patients with proliferative glomerulonephritis. In 38 of the 98 patients positive for CD16+ M phi population in urine, the CD16+ Mo population was negligible in peripheral blood. Immunohistochemically, CD16+ M phi were present in the glomeruli of active proliferative glomerulonephritis, whereas such cells were absent in inactive proliferative glomerulonephritis or nonproliferative glomerular diseases. CONCLUSION: CD16+ M phi may be effector cells involved in the acute inflammation common to all types of proliferative glomerulonephritis. Furthermore, the detection of CD16+ M phi in urine, as well as urinary M phi counts, may serve as a useful indicator of the active stage of proliferative glomerulonephritis.

A case of angiocentric T-cell lymphoma presenting as lethal midline granuloma.

A case of angiocentric T-cell lymphoma with glabellar skin being the only affected site was reported. A 43-year-old woman had a several months' history of glabellar swelling followed by progressive and destructive ulceration of the region. Histopathology of the biopsied specimen showed panniculitis with atypical lymphocytes and degenerative vessels filled with atypical cells. Most of the infiltrated lymphocytes were positive for CD2, CD3, CD4 and CD5. Antibodies to Epstein-Barr virus were detected in the patient serum. Intensive chemotherapy using a protocol of the L17M regimen was partially effective for clinical manifestations. Angiocentric T-cell lymphoma presenting as lethal midline granuloma is a rare but distinct entity with an acute fatal course.

Smooth tubular aggregates associated with plasmalemmal invagination in alveolar soft part sarcoma.

The ultrastructure of four alveolar soft part sarcomas was examined to search for ultrastructural signs of myogenic or neural origin. A new ultrastructural structure, an unusual tubular structure, was found in two of four cases. The structure appeared as a large, smooth, tubular aggregate in the cytoplasm of some tumor cells but did not show a honeycomb arrangement of tubules. The aggregate was composed of long, serpentine, branching, smooth, irregularly arranged tubules without ribosomes that ran in various directions. The aggregates intermingled with small amounts of cytoplasmic organelles. Because the aggregated tubules were at times continuous with cell membranes, it was shown that they were the complex extensions or invaginations of cell membranes. Neither myelin-axon complexes nor myofilaments, including Z band material, were seen in any case. There was a possibility that the smooth tubular aggregate was a T-tubule-like structure, suggesting that the tumors were derived from skeletal muscle cells.

Morphogenesis and origin of fibrous long-spacing collagen fibers in collagenase-treated mouse skin tissues.

Morphogenesis and origin of fibrous long-spacing collagen (FLS) fibers in newborn mouse skin tissues treated with collagenase were examined using ultrastructural observation, morphometry, histochemical methods, and immunoelectron microscopy. The enzyme caused both the partial destruction of basal laminae and the formation of abundant FLS fibers in the dermal matrix. The fibers were usually distributed in the vicinity of basal laminae in the capillaries or basal layer cells. The fibers were characterized by the cross-striated dark bands with about 91 nm periodicity and longitudinally aligned filaments with a diameter of about 6.5 nm. The dark bands of FLS fibers were often continuous with the basal laminae. Histochemical results showed that the dark bands contained the similar mucopolysaccharides which were involved in the basal laminae. Immunoelectron microscopic results showed that laminin was present in the dark bands as well as in the basal laminae, and that type VI collagen was located in the filaments of FLS fibers. These results suggest that the dark bands are formed by products similar to basal laminae and that the products were precipitated on type VI collagen-contained filaments with periodic intervals of about 91 nm. Morphometric examination revealed that there was no differences in ultrastructure between FLS fibers of a collagenase-treated mouse and those of a human neural tumor.

[Studies on HLA typing in a family line with spontaneous pneumothorax].

Our patient with spontaneous pneumothorax is the oldest brother of 3 siblings. Pneumothorax had occurred in his younger sister and in 3 of his mother's 4 siblings also. Namely, pneumothorax had occurred in 5 (including our patient) of 7 persons, family line on mother's side, and thoracotomy had been performed in 3 of them. Two cases in which operative findings were obtained were introduced. Next, HLA and alpha 1-antitrypsin (alpha 1-AT) were determined in this family line. As the result, the alpha 1-AT all remained in the normal range and HLA typing was not in a special relation to the occurrence of pneumothorax in this family line.

Study on the biodistribution of deuterated biomolecules in mice aiming at new diagnostic radio-imaging agents.

Deuterated compounds (2H-compounds) labeled with 14C prepared from deuterated algae, Chlorella ellipsoidea, were examined for their time-coursed distribution in mice after intravenous administration. The 14C-2H-compounds were fractionated and isolated from algae grown in practically 100 mol% 2H2O in the presence of 14C-bicarbonate. The fractions obtained were the "basic" and "acid" fractions, composed mainly of amino acids and sugar phosphates, respectively, and glucose, galactose, and lipid fractions. All fractions were examined for their biodistribution in mice bearing Ehrlich solid tumor in comparison with the fractions isolated from ordinary Chlorella (1H-Chlorella). 2H-Compounds thus examined showed some behaviors different from 1H-compounds. The 2H- "basic" fraction distributed more slowly in heart, lung and liver than the 1H-fraction. The 2H-specific large distribution in tumor was also observed on this fraction. The 2H-dependent characteristics in the distribution of glucose and galactose differed. The 2H-glucose level was lower in blood and higher in brain, resulting in a brain/blood ratio approximately twice that of 1H-glucose, while 2H-galactose did not show such a characteristic. These findings may be useful for the application of 2H-biomolecules to functional radio-imaging agents for nuclear medicine.

[Chondrosarcoma of the ribs: report of two cases].

Chondrosarcoma of rib origin is relatively rare in Japan. Two patients with chondrosarcoma of rib origin were treated surgically. Case 1: A 79-year-old male, 4 years ago, he noticed a tumor in the left anteroinferior part of the chest. The histological examination of the specimen obtained by incisional biopsy showed osteochondroma in another hospital and he had been under observation. Since the tumor has recently increased in size, he was referred to our department. Radical resection of the chest wall was performed. As expected, the tumor was found to be a secondary chondrosarcoma by postoperative histological examination. Case 2: A 49-year-old female. In the follow up studies after radical nephrectomy, Tc-MDP scintigram revealed an accumulation in the left second rib. Under the diagnosis of rib metastasis, radical resection was performed. The histological examination showed chondrosarcoma of rib origin postoperatively. This lesion was a primary central type, and is considered to have been resected in the earliest stage of all cases we have found in the Japanese literature.

[Angiographic findings in a patient with spontaneous hemopneumothorax].

We experienced one patient with spontaneous hemopneumothorax in whom angiography was performed preoperatively. The patient was a 23-year-old female and her plain chest X-ray revealed an index-finger-tip-sized bulla at the left apex and a narrow restiform shadow connecting the pleural cupola with the bulla. Left subclavian arteriography revealed preoperatively that the restiform shadow consisted of aberrant vessels branched from the left costocervical trunk and distributed in and around the bulla at the apex. In the present study very rare angiographic findings and excised specimens obtained from the patient are shown, with reference to surgical indication of spontaneous pneumothorax.

[Traumatic diaphragmatic hernia].

Five cases of traumatic diaphragmatic hernia were reported and 495 cases reported in Japan were reviewed. Analysis of cases of hernia following blunt trauma in the present study provided a simple classification of fissure of the diaphragm, i.e., "tension type (indirect type)" and "impact type (direct type)". In the former type, the fissure occurs in the central tendon or its vicinity in the diaphragm as a result of distortion of the bony thorax without direct force on the diaphragm, while in the latter type, the fissure occurs in the diaphragm close to the struck bony thorax as a result of blunt force on the bony thorax to which the diaphragm is attached.

Preparation of zein microspheres conjugated with antitumor drugs available for selective cancer chemotherapy and development of a simple colorimetric determination of drugs in microspheres.

Zein microspheres conjugated with antitumor drugs (mitomycinc (MMC), daunomycin hydrochloride (DM), peplomycin sulfate (PEP] were prepared by using a dimethyl sulfoxide (DMSO)-H2O system. MMC with low solubility in H2O was easily entrapped by the standard procedure, whereas some modifications were required for moderately and highly soluble drugs such as DM and PEP. Colorimetric determination of the drugs in microspheres was easily achieved by use of the phenol-sulfuric acid method for drugs with sugar moieties in their molecules, such as DM and PEP, while a simple treatment of the microspheres with concentrated sulfuric acid was applied in the case of drugs having a chromophore in their molecules, such as DM and MMC.

Novel preparation of zein microspheres conjugated with PS-K available for cancer immunotherapy.

Microspheres which entrapped PS-K were prepared using Zein as a carrier matrix by a one-step or two-step process in dimethyl sulfoxide-H2O media. Microspheres prepared by the latter process provided satisfactory recovery and uptake of PS-K. Use of a catalytic amount of dl-camphorsulfonic acid, glutaraldehyde and rapid addition of aqueous solution of polyvinylpyrrolidone into the reaction media are crucial for the preparation of fine and mono-dispersed microspheres. The release rate of PS-K could be controlled by altering the ratio of PS-K to Zein and the conditions of the medium. In the presence of actinase E, drug release was considerably increased to 70-80% after 24 h incubation. Sonication of the aggregated microspheres readily yielded a mono-dispersed preparation with a particle diameter of less than 1 micron, which would be a suitable size for phagocytosis by macrophages.

Tumor accumulation of D-selenomethionine-75Se in tumor-bearing mice.

The radioactivity distribution of 75Se-labeled D-selenomethionine (D-SeMet-75Se) was investigated in tumor-bearing mice in order to develop a new radioactive diagnostic agent. D-SeMet-75Se was enzymatically prepared from commercially available L-selenomethionine-75Se (L-SeMet-75Se) by using amino acid racemase and immobilized L-amino acid oxidase. No difference between D- and L-SeMet-75Se was found in the excretion rate into urine and feces in normal mice within 48 h after administration. The in vivo uptake of D-SeMet-75Se in both Ehrlich solid tumor and sarcoma-180 solid tumor was several times higher than that of L-SeMet-75Se but the uptake of D- and L-SeMet-75Se were similar in the pancreas. These results indicated that D-SeMet-75Se might be useful as a tumor-imaging agent. In vitro experiments on Ehrlich ascites tumor cells showed that D-SeMet-75Se was incorporated into the tumor cells by a Na+-dependent active transport system similar to L-SeMet-75Se and that a transport mechanism specific for D-SeMet-75Se might be present in tumor cells in addition to a transport system common to both D- and L-forms.