Study On The Correlation Between Epidermal Cyst And HPV Infection

Background:Presently,epidermal cysts originate from damaged hair follicle structures or traumatic implantable epithelium,usually asymptomatic when it is not inflamed,however,when there is secondary infection it can cause pain and discomfortable feeling.In addition to that,a very small number of epidermal cysts can cause squamous cell carcinoma or basal cell carcinoma.In our clinical work,we found that some of the epidermal cysts showed a significant manifestations that transparent keratinocytes in the parietal cavity of the proximal cavity are increased and thick,large and round keratinized nucleus,as well as keratinocytes are partly turned to be vacuolar cells,which represents the histological changes of HPV infection.We suggest that HPV infection may be associated with the formation of epidermal cyst.The literature found that there were many reports about which HPV 57 and 60 were associated with the formation of epidermal cysts in the palmoplantar epidermal cysts.The epidermal cysts in non-palmoplantar sites that we found in our clinical work also have the evidence of HPV infection.Thus,we guess that epidermal cysts with non-palmoplantar sites may also be associated with HPV infection.Human papillomavirus(HPV)is a class of double-stranded DNA viruses that invade human skin and mucosal epithelium.More than 170 kinds of papillomaviruses have been identified.It is confirmed that HPV infection can cause a variety of diseases,including warts,Epidermodysplasia Verruciformis,Bowenoid papulosis,condylomata acuminata,especially benign and malignant tumors,including seborrheic keratosis,squamous cell carcinoma,basal cell carcinoma,actinic keratosis,cervical cancer,ovarian cancer and so on.HPV can be divided into skin type and mucosal type,which has a strong epithelium,it can through the tiny damage into the epidermis and mucosal epithelium,lurking in the epithelial basal cells,when the time is suitable it enter into the keratinocytes for proliferation and infect the nucleus to form vacuolar cells.The vacuolar cells is of great significance in the diagnosis of HPV infection in histopathology.There are many kinds of relatively sensitive methods to detect HPV,such as immunohistochemisty,in situ hybridization,PCR and other detection methods,it can detect low levels of viral infection.Objectives:(1)To detect the presence of HPV in epidermal cysts and its related subtype;(2)To expand the disease spectrum caused by HPV infection;(3)To explore whether HPV infection is involved in the occurrence of epidermal cysts and to further the causes of epidermal cysts and the mechanisms of HPV infection that caused a variety of diseases.Materials and Methods:(1)57 cases of epidermal cysts were diagnosed by clinical and histopathological examination from dermatology clinic of Shandong Provincial Hospital,which were paraffined tissues(8 of 57 are also received fresh tissue).30 cases of normal skin are the control group.(2)All specimens were immunohistochemically stained to observe the rate of HPV infection.(3)DNA extraction was carried out by paraffin-based DNA extraction kit and the fresh tissue DNA extraction kit.The PCR primers were designed according to the literature.In order to detect the infection rate of HPV and the subtype of HPV in epidermal cyst,we were analyzed the PCR products by agarose gel electrophoresis and the human papillomavirus nucleic acid typing kit(fluorescence PCR method)which was used to detect 23 HPV subtype in epidermal cyst.(4)The data were analyzed by SPSS 22.0 software to calculate the P value.Results:(1)Immunohistochemistry(IHC):Among 57 cases of paraffinedepidermal cyst,there were 2 cases with strong positive(+++),4 cases with moderate positive(++),5 cases with weak positive(+).The cells in cyst wall with typically nuclear staining are mainly distributed in the prickle layers,a few distributed in the basal layer.Of the 11 cases of IHC-positive cases,9 cases were in the head and face,2 cases were in the trunk,the total positive rate of HPV in the case group was 21%(11/57),the positive rate in cases that possession of HPV infection characteristics was 44%(11/25),while the normal control skin was negative.Therefore,there was significant difference between the case group and the control group(P<0.05).(2)Polymerase chain reaction(PCR):only lof 57 epidermal cysts cases showed HPV 1,2,3,4,7,10,57 DNA positive,and the strip is poor,the remaining epidermal cyst and normal skin was negative.Human papillomavirus nucleic acid typing kit:It includes 23 mucosa related HPV subtypes that is 16,18,31,33,35,39,45,51,52,56,58,59,66,68,6,11,42,43,44,53,81,73,82,all samples in the fluorescence PCR instrument showed negative results.There was no significant difference between the case group and the control group(P>0.05).Conclusion:HPV infection may be associated with the occurrence of epidermal cysts in non-palmoplantar sites,whereas the specific sutype should be further confirm.PCR and IHC may not be sensitive to the sample in this experiment.