Laboratoire de Biologie des Cancers, Equipe Micro-organismes et Facteurs Oncogènes, Faculté de Médecine et de Pharmacie, Fez, Morocco.
Int J Biol Markers. 2010 Oct-Dec;25(4):179-84.
The RAS/RAF/MEK/MAP kinase cascade transduces signals from the cell surface to the nucleus in order to control cellular responses including proliferation, differentiation and survival. We investigated the occurrence of BRAF exon 15 and KRAS codon 12 and 13 mutations in Moroccan patients with colorectal cancer.
Sixty-two samples from patients with sporadic colorectal adenocarcinomas were studied for BRAF exon 15 and KRAS codon 12 and 13 mutations. DNA from paraffin-embedded tissue specimens was analyzed by a combination of polymerase chain reaction-high resolution melting and direct sequencing.
Of the analyzed specimens, 29% exhibited KRAS codon 12 or 13 mutations and only 1.6% carried a BRAF codon 600 mutation. KRAS mutations were more often observed in women (35.5%) than in men (22.6%). Patients in the age range between 41 and 60 years were more likely to be carriers of this mutation. No KRAS mutations were detected in patients aged >60 years.
Despite the limited study sample, our data suggest that KRAS mutations arise more frequently than BRAF mutations in Moroccan patients with colorectal carcinomas. The KRAS mutation status must be assessed in a large cohort of Moroccan patients to confirm these findings and to determine whether this mutation in combination with extrinsic, environmental or microenvironmental factors might be involved in the high frequency of colorectal cancer in middle-aged Moroccans.
RAS/RAF/MEK/MAP 激酶级联从细胞表面向细胞核传递信号，以控制包括增殖、分化和存活在内的细胞反应。我们研究了 BRAF 外显子 15 和 KRAS 密码子 12 和 13 突变在摩洛哥结直肠癌患者中的发生情况。
对 62 例散发性结直肠腺癌患者的样本进行了 BRAF 外显子 15 和 KRAS 密码子 12 和 13 突变分析。通过聚合酶链反应-高分辨率熔解和直接测序相结合的方法分析石蜡包埋组织标本中的 DNA。
在所分析的标本中，29%表现出 KRAS 密码子 12 或 13 突变，只有 1.6%携带 BRAF 密码子 600 突变。女性（35.5%）比男性（22.6%）更易发生 KRAS 突变。41 至 60 岁的患者更有可能携带这种突变。在年龄>60 岁的患者中未检测到 KRAS 突变。
尽管研究样本有限，但我们的数据表明，摩洛哥结直肠癌患者中 KRAS 突变的发生率高于 BRAF 突变。必须在大量摩洛哥患者中评估 KRAS 突变状态，以证实这些发现，并确定这种突变是否与外在的、环境或微环境因素相结合，可能参与了摩洛哥中年人群中结直肠癌的高发。
