Relationship Of HIF-1α, PCNA And VEGF With Microvascular Density In Cutaneous Squamous Cell Carcinoma And Basal Cell Carcinoma

Background and objectiveCutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) are common skin malignant tumors in plastic surgery. Which have the common feature as other malignant tumors. Hypoxia is the primary performance of malignant tumors. Angiogenesis and proliferation regulation of metabolism are the foundation to exist and invasion for tumor cell. Investigation to many malignant tumors show that hypoxia inducible factor- lα(HIF-1α) play a key role in autogenous regulation and adaption. HIF-1αis a transcription factor that can mediate hypoxia adaptation reaction. Vascular endothelial growth factor (VEGF) is now known as one of the strongest factor in promoting tumor angiogenesis. HIF-1αand VEGF participate the development of tumor through a few ways. CD105 is a specific marker for new vascular endothelial cell. Microvascular density (MVD) is generally considered as close to tumor angiogenesis. Proliferating cell nuclear antigen (PCNA) is a nuclear protein used to detect proliferating cell, which expression has a distinct difference in multiplication cycle. Up to now, As a new target, HIF-1αhas been a hot spot for tumor therapy. However, there is no final conclusion about the correlation of HIF-1α and proliferation. The relationship with HIF-1α,VEGF and proliferation , angiogenesis in SCC or BCC is not reported. In this study, we detected HIF-1αand VEGF proteins expression, calculated microvascular density marked with CD105 and proliferation index marked with PCNA by immunohistochemical in SCC, BCC and normal skin tissue to investigate the correlation among them to angiogenesis, formation, growth and metastasis, provide evidence to reasonable selection modus operandi and decision prognosis in clinic.Materials and methods1 Materials The tissues of SCC and BCC were obtained from 51 patients who underwent surgery; included 28 SCC and 23 BCC. Pathological grade of SCC:I 22; II 5; III 1. Carcinoma tissues were collected from scalp face, back, limbs and perineum. 20 human normal skin tissue samples were surplus transplanted free full thick skin graft collected away from non-carcinoma patients or cosmesisors.2 Methods Immunohistochemical SP method was used to detect expressions of HIF-1αand VEGF, calculated PI marked with PCNA and MVD marked with CD105. The data was analysed through package of software SPSS 11.0, and significance level is a=0.05,α=0.0167 after x~2 division.Results1 The expression of HIF-1αThe positive expression of HIF-1αwas mainly localized in the nuclei of tumor cells and part of vascular endothelial cells, there was a strong expression at the invading edge of tumor nests and necrotic regions. Part of vascular endothelial cell also could see the positive cells. The positive immunostaining rate of HIF-1αwas 82.14% (23/28) in SCC, 47.82% (11/23) in BCC respectively, 20 normal skin tissue were negative. The expression of HIF-1αwas significant difference between SCC or BCC and normal control (P<0.05), there also was a significant difference between SCC and BCC(P<0.05), The positive immunostaining rates of HIF-1αwas 77.27% (17/22) in well-differentiated SCC, and 100% (6/6) in moderately and poorly differentiated SCC respectively, The expression of HIF-1αin SCC was no significant relationship with pathological grade (P>0.05). 2 The expression of VEGF Distribution of VEGF was demonstrated within cytoplasm of tumor parenchymal cell, there was a weak expression in keratinocyte above the stratum basale epidermidis, part of vascular endothelial cells and external root sheath cells, the tumor cell adjoin the new vessels showed strong stained. The positive immunostaining rate of VEGF was 67.85% (19/28) in SCC, 30.43% (7/23) in BCC and 20.00%(4/20) in normal control respectively. The expression of HIF-1αwere significant difference between SCC or BCC and normal control (P<0.05), there was no significant difference between BCC and normal skin (P<0.05). The positive immunostaining rate of VEGF was 63.64% (14/22) in well-differentiated SCC, and 83.33%(5/6) in moderately and poorly differentiated SCC respectively, The expression of VEGF in SCC was no significant relationship with pathological grade(P>0.05).3 The expression of CD105 The positive expression of CD105 was mainlylocalized cytomembrane or cytoplasm of vascular endothelial cells in the stroma around tumor nests. MVD in SCC, BCC and normal skin were 14.87±3.48, 9.18±3.26 and 0.65±0.43 respectively. There was a significant difference between SCC or BCC and normal control (P<0.05), there also was a significant difference between SCC and BCC (P<0.05). MVD was 14.20±3.67 in tumor with HIF-1α(+) and 8.53±3.18 in tumor with HIF-1α(-), there was a significant difference between them (P<0.05), MVD is 15.16±3.37 in tumor with VEGF(+) and 9.34±3.25 in tumor with VEGF(-). The higher degree of angiogenesis was associated with increased expression of HIF-1αand VEGF. There also was a significant difference between them (P<0.05).4 The expression of PCNA The positive expression of PCNA was localized in the nuclei, PI in SCC, BCC and normal skin were 69.71±6.04, 53.11±5.32 and 20.12±4.77 respectively. There was a significant difference between SCC or BCC and normal control (P<0.05), there also was a significant difference between SCC and BCC (P<0.05). PI is 65.76±8.92 in tumor with HIF-1α(+) and 55.12±8.55 in tumor with HIF-1α(-), there was a significant difference between them (P<0.05). PI was 66.96±8.93 in tumor with VEGF(+) and 57.28±8.87 in tumor with VEGF(-), there also was a significant difference between them (P<0.05). 5 Correlation analysis Correlation analysis showed the expression of HIF-1αhad a positive relationship with the expression of VEGF (r=0.555, P<0.05). So did PI and MVD in BCC ( r=0.533, P<0.01). There was no correlation between PI and MVD (r=0.360, P>0. 05).Conclusion1 Overexpression of HIF-1αin SCC and BCC, there was a positively correlation with VEGF, MVD, PI respectively. It indicated there was a close relationship among HIF-1αand angiogenesis or cell proliferation in SCC and BCC, It maybe promote the growth and invasion and can be used as a factor to judge prognosis of SCC or BCC.2 Overexpression of VEGF in SCC and BCC, with higher MVD and PI in tumor VEGF(+) than VEGF(-) indicated there was a close relationship among VEGF and angiogenesis or cell proliferation in SCC. However, there was no significant difference expression between BCC and normal skin. It maybe concerned with the bio-behaviour of BCC such as growth torpidity and seldom metastasis. MVD and PI with positive expression of VEGF were much higher than negative reflected the general behaviour of malignant tumor. It is not enough evidence to evaluate the prognosis of BCC by VEGF.3 The expression of HIF-1αhad a positive relationship with the expression of VEGF, MVD in SCC or BCC. The expression of VEGF in BCC was close to normal skin, but MVD was much higher than normal skin suggest HIF-1αis not only up-regulate the expression of VEGF but also by other ways to promote tumor angiogenesis.4 Detection of HIF-1α, MVD, PI in SCC and BCC maybe helpful to get the message of biological behaviour. Which provide the theoretic basis for prevention and therapy in clinic.