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Aims: MITF, TFE3, TFEB and TFEC belong to the same microphthalmia‐associated transcription factor family (MiT). Two transcription factors in this family have been identified in two unusual types of renal cell carcinoma (RCC): Xp11 translocation RCC harbouring TFE3 gene fusions and t(6;11) RCC harbouring a MALAT1–TFEB gene fusion. The 2016 World Health Organisation classification of renal neoplasia grouped these two neoplasms together under the category of MiT family translocation RCC. RCCs associated with the other two MiT family members, MITF and TFEC, have rarely been reported. Herein, we identify a case of MITF translocation RCC with the novel PRCC–MITF gene fusion by RNA sequencing. Methods and results: Histological examination of the present tumour showed typical features of MiT family translocation RCCs, overlapping with Xp11 translocation RCC and t(6;11) RCC. However, this tumour showed negative results in TFE3 and TFEB immunochemistry and split fluorescence in‐situ hybridisation (FISH) assays. The other MiT family members, MITF and TFEC, were tested further immunochemically and also showed negative results. RNA sequencing and reverse transcription–polymerase chain reaction confirmed the presence of a PRCC–MITF gene fusion: a fusion of PRCC exon 5 to MITF exon 4. We then developed FISH assays covering MITF break‐apart probes and PRCC–MITF fusion probes to detect the MITF gene rearrangement. Conclusions: This study both proves the recurring existence of MITF translocation RCC and expands the genotype spectrum of MiT family translocation RCCs. [ABSTRACT FROM AUTHOR]

Aims The aim of this study was to investigate potential molecular mechanisms associated with loss of BRM expression in poorly differentiated clear cell renal cell carcinoma (cc RCC). Methods and results Nineteen previously selected BRM-negative RCC tissues were examined by DNA sequencing, fluorescence in-situ hybridization ( FISH) and methylation-specific polymerase chain reaction ( PCR) of the BRM gene. BRM mutation was identified in 78.9% (15 of 19) cases, chromosome 9 monosomy or BRM deletion in 43.8% (seven of 16) and BRM promoter region cytosine-phosphate-guanine (CpG) methylation in 42.8% (six of 14). These results indicated that 89.5% (17 of 19) of the cases harboured at least one type of BRM genetic alteration, with two or more types of alteration in 47.4% (nine of 19). Such alterations were found rarely in adjacent non-neoplastic tissues and low-grade areas of composite tumours. Conclusions BRM gene mutation, chromosome 9 monosomy or BRM deletion and CpG methylation contribute collectively to the loss of BRM expression in cc RCC. This work focusing on composite tumours indicated that BRM abnormality occurred during tumour progression. [ABSTRACT FROM AUTHOR]

Recently, an increasing number of TFE3 rearrangement-associated tumours have been reported, such as TFE3 rearrangement-associated perivascular epithelioid cell tumours ( PEComas), melanotic Xp11 translocation renal cancers and melanotic Xp11 neoplasms. We have suggested that these tumours belong to a single clinicopathological spectrum. 'Xp11 neoplasm with melanocytic differentiation' or 'melanotic Xp11 neoplasm' have been proposed to designate this unique neoplasm. Herein, we describe the first case of an Xp11 neoplasm with melanocytic differentiation to be described in the prostate, bearing the novel NONO- TFE3 gene fusion. This study both adds to the spectrum regarding melanotic Xp11 neoplasms and expands its gene fusion spectrum. Moreover, we discuss the relationship of these rare tumours to neoplasms such as conventional PEComas, alveolar soft part sarcomas, malignant melanomas, clear cell sarcomas and Xp11 translocation renal cancers. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to investigate potential molecular mechanisms associated with loss of BRM expression in poorly differentiated clear cell renal cell carcinoma (ccRCC)., Methods and Results: Nineteen previously selected BRM-negative RCC tissues were examined by DNA sequencing, fluorescence in-situ hybridization (FISH) and methylation-specific polymerase chain reaction (PCR) of the BRM gene. BRM mutation was identified in 78.9% (15 of 19) cases, chromosome 9 monosomy or BRM deletion in 43.8% (seven of 16) and BRM promoter region cytosine-phosphate-guanine (CpG) methylation in 42.8% (six of 14). These results indicated that 89.5% (17 of 19) of the cases harboured at least one type of BRM genetic alteration, with two or more types of alteration in 47.4% (nine of 19). Such alterations were found rarely in adjacent non-neoplastic tissues and low-grade areas of composite tumours., Conclusions: BRM gene mutation, chromosome 9 monosomy or BRM deletion and CpG methylation contribute collectively to the loss of BRM expression in ccRCC. This work focusing on composite tumours indicated that BRM abnormality occurred during tumour progression., (© 2016 John Wiley & Sons Ltd.)