The neurofibromin 1 type I isoform predominance characterises female population affected by sporadic breast cancer: preliminary data
- Daniel Marrero1,2,
- Raúl Peralta1,
- Alejandra Valdivia1,
- Antonio De la Mora2,
- Pablo Romero1,
- Miriam Parra1,
- Nayeli Mendoza1,
- Monica Mendoza1,
- Dalila Rodriguez1,
- Ernesto Camacho3,
- Armando Duarte3,
- German Castelazo4,
- Enrique Vanegas5,
- Israel Garcia6,
- Claudia Vargas2,
- Diego Arenas7,
- Florinda Jimenez2,
- Mauricio Salcedo1
- 1Laboratorio de Oncogenómica, Unidad de Investigación Médica en Enfermedades Oncológicas, Hospital de Oncología, CMN-SXXI, IMSS, Mexico, D.F
- 2Laboratorio de Biotecnología, Universidad Autonóma de Ciudad Juárez, Cd. Juárez, Chihuahua, Mexico
- 3Clínica de Mama, Hospital General de Zona #35, IMSS, Cd. Juárez, Chihuahua, Mexico
- 4Servicio de Mama, Hospital de Ginecología #3, CMN La Raza IMSS, México, D.F
- 5Departamento de Patologia, Escuela de Medicina, Universidad Autonóma de Ciudad Juárez, Cd. Juárez, Chihuahua, Mexico
- 6Servicio de Cirugia Oncologica, Hospital de Oncología CMN-SXXI, IMSS, Mexico, D.F
- 7Unidad de Investigación Medica en Genetica Humana, Hospital de Pediatria, CMN-SXXI, Mexico, D.F
- Correspondence to Dr Mauricio Salcedo, Laboratorio de Oncogenómica, Unidad de Investigacion Medica en Enfermedades Oncologicas, Hospital de Oncologia, CMNSXXI-IMSS, Av. Cuauhtémoc 330, Col. Doctores, México D.F., Mexico;
Contributors DM, MS and FJ conceived and designed the study, analysed data and drafted the manuscript; RP, AV, PR, CV, DA, DR, NM, MP, AD and MM helped with RNA extraction, RT-PCR and immunohistochemistry assays; and EC, AD, GC, EV and IG provided biological samples and clinical data. All authors have approved the final version of this manuscript.
- Accepted 30 December 2011
- Published Online First 12 March 2012
Aims Neurofibromin 1 (NF1) as a tumour suppressor gene can give rise to several transcripts by an alternative splicing event, generated at least for CELF cofactors. At present, the NF1 isoforms and CELF splicing transcripts in sporadic breast cancer are unknown. The aim of the authors was to detect NF1 gene expression, the NF1 isoform ratio and the CELF transcripts present in sporadic breast cancer.
Methods Neurofibromin and RAS expression were analysed on tissue microarrays containing sporadic breast cancer (n=22), benign lesions (n=18, including six fibroadenomas, six fibrocystic changes and six ductal hyperplasias) and normal breast tissue (n=6) by immunohistochemistry assay. NF1 and CELF 3–6 RNA expression was performed by end point reverse transcription-PCR in the breast samples.
Results NF1 and RAS expression in breast tissues showed no differential expression by immunohistochemistry results. Interestingly, the authors observed a shift transition in the isoform transcripts, from type II in normal breast tissue to type I isoform in breast carcinomas. CELF cofactor expression failed to be related with the shift transition of NF1 in breast tissues.
Conclusions These data suggest that there is a tendency for an NF1 expression shift transition from type II to type I isoform, which could comprise a significant event in the development and progression of sporadic breast cancer. This shift transition may not be related with CELF cofactors.
Funding This work was partially supported by grants 69719 and 87244 from Fondos Sectoriales CONACYT-Mexico.
Competing interests None.
Patient consent Patient consent was obtained according to Helsinki declaration.
Provenance and peer review Not commissioned; externally peer reviewed.