Clinicopathological and molecular genetic characteristics of ELOC mutated renal cell carcinoma / 中华病理学杂志

Objective: To investigate the clinicopathological features, molecular genetic features, differential diagnosis and prognosis of ELOC mutated renal cell carcinoma. Methods: From January 2015 to June 2022, 11 cases of renal cell carcinoma with clear-cell morphology, expression of CAⅨ and CK7 and no 3p deletion were collected. Two cases of ELOC mutant renal cell carcinoma were diagnosed using whole exome sequencing (WES). The clinical features, morphology, immunophenotype, FISH and WES results were analyzed. The relevant literature was reviewed. Results: The two patients were both male, aged 29 and 51 years, respectively. They were both found to have a renal mass by physical examination. The maximum diameters of the tumors were 3.5 cm and 2.0 cm, respectively. At the low magnification, the tumors were well-defined. The tumor cells showed a pushing border and were separated by thick fibrous bands, forming nodules. The tumor cells were arranged in a variety of patterns, including tubular, papillary, solid nest or alveolar. At high magnification, the tumor cells were large, with well-defined cell borders and clear cytoplasm or fine eosinophilic granules. CAⅨ was diffusely box-like positive in both cases. Case 1 was partially and moderately positive for CK7, strongly positive for CD10, diffusely and moderately positive for P504S, and weakly positive for 34βE12. In case 2, CK7 and CD10 were both partially, moderately positive and P504s were diffusely positive, but 34βE12 was negative. FISH results showed that both cases had no 3p deletion. ELOC c.235T>A (p.Y79N) mutation was identified using WES in case 1, while ELOC c.236_237inv (p.Y79C) mutation was identified in case 2. Conclusions: As a new clinical entity, ELOC mutated renal cell carcinoma may be underdiagnosed due to its overlap with clear cell renal cell carcinoma in morphology and immunophenotype. The diagnosis of renal cell carcinoma with ELOC mutation should be confirmed by morphology, immunohistochemistry, FISH and gene mutation detection. However, more additional cases are needed to explain its biological behavior and prognosis.

Myocardial biopsy of Liwen procedure: representability and etiological diagnostic value of cardiac samples obtained by a novel technique in patients with hypertrophic cardiomyopathy / 中华心血管病杂志

Objective: To investigate the representability and etiological diagnostic value of myocardium samples obtained from patients with hypertrophic cardiomyopathy (HCM) by transthoracic echocardiography-guided percutaneous intramyocardial septal biopsy (myocardial biopsy of Liwen procedure). Methods: This study was a retrospective case-series analysis. Patients with HCM, who underwent myocardial biopsy of Liwen procedure and radiofrequency ablation in Xijing Hospital, Air Force Military Medical University from July to December 2019, were included. Demographic data (age, sex), echocardiographic data and complications were collected through electronic medical record system. The histological and echocardiographic features, pathological characteristics of the biopsied myocardium of the patients were analyzed. Results: A total of 21 patients (aged (51.2±14.5) years and 13 males (61.9%)) were enrolled. The thickness of ventricular septum was (23.3±4.5)mm and the left ventricular outflow tract gradient was (78.8±42.6)mmHg (1 mmHg=0.133 kPa). Eight patients (38.1%) were complicated with hypertension, 1 patient (4.8%) had diabetes, and 2 patients (9.5%) had atrial fibrillation. Hematoxylin-eosin staining of myocardial samples of HCM patients before radiofrequency ablation evidenced myocytes hypertrophy, myocytes disarray, nuclear hyperchromatism, hypertrophy, atypia, coronary microvessel abnormalities, adipocyte infiltration, inflammatory cell infiltration, cytoplasmic vacuoles, lipofuscin deposition. Interstitial fibrosis and replacement fibrosis were detected in Masson stained biopsy samples. Hematoxylin-eosin staining of myocardial samples of HCM patients after radiofrequency ablation showed significantly reduced myocytes, cracked nuclear in myocytes, coagulative necrosis, border disappearance and nuclear fragmentation. Quantitative analysis of myocardial specimens of HCM patients before radiofrequency ablation showed that there were 9 cases (42.9%) with mild myocardial hypertrophy and 12 cases (57.1%) with severe myocardial hypertrophy. Mild, moderate and severe fibrosis were 5 (23.8%), 9 (42.9%) and 7 (33.3%), respectively. Six cases (28.6%) had myocytes disarray. There were 11 cases (52.4%) of coronary microvessel abnormalities, 4 cases (19.0%) of adipocyte infiltration, 2 cases (9.5%) of inflammatory cell infiltration,6 cases (28.5%) of cytoplasmic vacuole, 16 cases (76.2%) of lipofuscin deposition. The diameter of cardiac myocytes was (25.2±2.8)μm, and the percentage of collagen fiber area was 5.2%(3.0%, 14.6%). One patient had severe replacement fibrosis in the myocardium, with a fibrotic area of 67.0%. The rest of the patients had interstitial fibrosis. The myocardial specimens of 13 patients were examined by transmission electron microscopy. All showed increased myofibrils, and 9 cases had disorder of myofibrils. All patients had irregular shape of myocardial nucleus, partial depression, mild mitochondrial swelling, fracture and reduction of mitochondrial crest, and local aggregation of myofibrillary interfascicles. One patient had hypertrophy of cardiomyocytes, but the arrangement of muscle fibers was roughly normal. There were vacuoles in the cytoplasm, and Periodic acid-Schiff staining was positive. Transmission electron microscopy showed large range of glycogen deposition in the cytoplasm, with occasional double membrane surround, which was highly indicative of glycogen storage disease. No deposition of glycolipid substance in lysozyme was observed under transmission electron microscope in all myocardial specimens, which could basically eliminate Fabry disease. No apple green substance was found under polarized light after Congo red staining, which could basically exclude cardiac amyloidosis. Conclusion: Myocardium biopsied samples obtained by Liwen procedure of HCM patients are representative and helpful for the etiological diagnosis of HCM.

Bortezomib depresses osteoblast apoptosis induced by mouse myeloma cells / 中国实验血液学杂志

The purpose of this study was to explore the effect of proteasome inhibitor, bortezomib (Bzb), on osteoblast in pathologic status of myeloma bone disease. The myeloma bone disease was modeled by co-culture of mouse myeloma cell RPMI8226 with osteoblast line MC-3T3E1 from mouse calvaria, and intervenient culture of supernatant. The inhibitory effect of Bzb on proliferation of MC-3T3E1 assayed by modified MTT method, the apoptosis of MC-3T3E1 cells was determined by flow cytometry with Annexin V/PI staining, the expressions of osteoblast markers, Runx2/cbfa1, osteocalcin (OCN) and osterix (OSX) in MC-3T3E1 treated with Bzb were detected by RT-PCR and Western blot respectively. Experiments were divided into 3 group: single cultured, co-cultured and supernatant-interveniently cultured groups. The results showed the Bzb in higher concentration inhibited proliferation of MC-3T3E1 cells in a dose-dependent manner, with the IC(50) of 38.1 nmol/L for 48 hours, the Bzb in low concentration (5 nmol/L) did not show the inhibitory effect on proliferation of MC-3T3E1 in single cultured group (p>0.10), but could decrease apoptotic rate of MC-3T3E1 by 32.5% and 24.6% respectively in cocultured and supernatant-interveniently cultured groups, moreover increased the expression of osteoblast-related gene OSX, OCN mRNA and protein (p<0.05), while no obvious change of Runx2/cbfa1 expression was observed (p>0.05). It is concluded that the proteasome inhibitor, Bzb, in low concentration promotes the activity of osteoblast internal mechanisms, and prevents the apoptosis of osteoblasts induced by myeloma cells. In addition, it can up-regulate transcription and expression of osteoblast markers related to Runx2/cbfa1 path way, thus may protect osteoblasts in myeloma bone disease.