Association of Exon 9 FGFR3 Mutations and Cancer Grads in Patients with Bladder Cancer

Abstract

Bladder cancer is the ninth most common cancer diagnosis worldwide, with more than 330,000 new cases each year and more than 130,000 deaths per year, with an estimated male: female ratio of 3.8:1.0. According to the most recent Iraqi cancer record (Iraqi cancer registry, 2010), bladder carcinoma is currently ranks sixth among the commonest ten cancers. Previous studies indicated that genetic alterations were involved in bladder cancer.

To detect genetic alteration in exon 9 of FGFR3 gene, 50 patients with different grads of bladder cancer who admitted to Ghazi AL-Hariri Hospital in Baghdad and 25 healthy persons aged between 30 to 86 years were included in this study. DNA was extracted from blood samples from patients and healthy control. PCR was conducted using special primers. Mutations of exon 9 of the FGFR3 gene were screened by sequencing and the patients sequencing results were compared with human reference FGFR3 gene sequence (NCBI Reference Sequence: NG_012632.1).

Among 50 patients included in this study, 30 (37%) patients were with mutations detected in exon 9 which include novel g.16026 del G and g.16024 sub G>C mutations. The more frequent mutation was g.16026 del G (22, 70%) followed by g.16024 sub G>C mutation (8, 30%). Moreover, the results showed that three patients were with compound mutations (with both exon 9 mutations).

Exon 9 mutations (g.16024 sub G to C and g.16026 del G) showed an association with cancer initiation and metastasis since they detected in grad I and II.