Cervical cancer is the mainly cause of cancer death in women in many developing countries, accounting for 20-30% of women's cancer. It is the second most common form of cancer in women worldwide after breast cancer with nearly 500,000 new annual cases. In Africa, it is the first. Most cervical cancers follow intraepithelial cervical dysplasia or neoplasia, which is most often the result of infection with human papillomavirus (HPV). Genital HPV infection is considered the most common sexually transmitted infection (STI) in the world. Under immunocompetence conditions, the virus is eliminated within 12 to 18 months of infection. But in most cases especially in developing countries infection with one of the high-risk oncogenic HPV is responsible for most cancers of the cervix. We therefore considered that it was important to study the portage and to characterize HPV genotypes in a sexually active population of women by focusing on high-risk genotypes in order to develop cartography of HPV in the West Africa region.
But another important parameter in HPV infection evolution through cervical lesion and cancer is the genetic factor of host. Some authors suggest that the genetic background of the host could facilitate this persistence even promote infection itself and progression to injury. The polymorphisms of certain genes seem to influence the risk of acquisition and clearance of HPV infection or HPV infection and its evolution through cervical lesions and cancer. Many pathogenic genes associated to HPV or Cervical cancer have been verified through biological experiments. Among these genes, KIR, HLA, CYP1A1, GSTM1, PIK3CA, MMP1 and MMP3 appear to have a strong association with HPV infection and related cervical lesion or cancer.
Knowing that several genes of the immune or cell cycle system may be involved in genetic resistance to HPV and cervical cancer in others counties, which are those that are found in West Africa? The presence of certain mutations of KIR, HLA, CYP1A1, GSTM1, PIK3CA, MMP1 and MMP3 genes could it have an impact on cervical cancer trends among women infected by HPV in West Africa?
To answer these questions, we would like to investigate on the distribution of KIR, HLA, CYP1A1, GSTM1, PIK3CA, MMP1 and MMP3 gene in West African women positive for HPV infection and/or cervical lesion comparatively to control subjects.
Moreover, in our context of poor countries, we must especially focus on the prevention of cancer. And to be effective in the prevention, we need to have as much information on HPV and genetic factors of the women of the West Africa which could promote the progression to cancer. We believe that the results of this study will help our governments in their fight against cervical cancer.
The study population will consist of 2000 cervical samples from 2000 women in six counties (Benin, Burkina Faso, Côte-d’Ivoire, Mali, Niger and Togo) of West Africa (nine towns with around 222 samples by town) and 308 samples of cervical tissues archived, fixed and paraffin-embedded from Burkina Faso and Benin with histological diagnosis of CIN-I, CIN-II, CIN-III and cervical cancer. KIR, HLA, CYP1A1, GSTM1, PIK3CA, MMP1 and MMP3 gene will be characterized by PCR-RFLP, SSP-PCR, followed by gel electrophoresis and Real-Time PCR. The samples with interesting mutations will be sequenced.