Molecular Detection and Typing of Human Papillomaviruses in Paraffin-Embedded Cervical Cancer and Pre-Cancer Tissue Specimens

Abstract

Background: Cervical cancer is one of the important reasons of mortality among females. Prevention, early diagnosis and immediate treatment can affect the rate of mortality in this cancer and several epidemiological studies have shown a strong relationship between human papilloma viruses (HPVs) and cervical cancer.

Objectives: The present study was conducted to survey HPV infections in a women population with cervical cancer and cervical dysplasia/metaplasia in southwest of Iran.

Materials and methods: 72 paraffin-embedded cervical biopsies which had been previously archived from women with cervical cancer and cervical dysplasia were examined by polymerase chain reaction (PCR). Afterward, the detected HPV strains were typed by restriction fragment length polymorphism (RFLP) analysis of PCR amplicons.

Results: 60 out of 72 samples had necessary requirements and HPV DNA was detected in 43.3% of these samples. Most HPV positive samples belonged to women aged from 48 to 63 years. On the other hand, HPV infection among patients with squamous cell carcinoma (SCC) was 48.78% and in women with dysplasia/metaplasia was 26.66%. The most prevalent type of the human papilloma virus was HPV16 (100%).

Conclusions: Knowing the most prevalent type of the human papilloma viruses circulating in the population (HPV16) can be applied in the future screening and managing programs of this major disease and also in vaccination against the prevalent types of the virus. Meanwhile, it seems that more studies should be performed to determine the role of different risk factors involved in development of the disease, especially those related with social behaviors and traditions with respect to different areas.

Keywords: Cervical Cancer; Human Papilloma Viruses; PCR; RFLP.

Figure 1.. Agarose gel Electrophoresis of Products of Human β-globin PCR

Lane L, 100 bp DNA ladder (Fermentas); lane 11, negative control contained no template DNA. 268 bp amplified DNA fragment can be seen in several lanes (e.g. lanes 1, 2, 3, 4) and not in lanes 5, 6, 7.

Figure 2.. Agarose gel Electrophoresis of Products of HPV PCR

Lane L, 100 bp DNA ladder (Fermentas); lanes 2 and 6, HPV positive samples contained 450 bp amplicon from HPV genome.

Figure 3.. Restriction Fragment Length Polymorphism Pattern Generated by RsaI Digestion of the HPV PCR Products

Lane L, 100 bp DNA ladder (Fermentas); lanes 2 and 3 contain 310 and 70 bp DNA fragments produced from enzymatic digestion; lane 3, undigested 450 bp product of HPV PCR as a control.