Endogenous survivin modulates survival and proliferation in UVB-treated human keratinocytes

Anthocyanin from Lycium ruthenicum Murr. in the Qaidam Basin Alleviates Ultraviolet-Induced Apoptosis of Human Skin Fibroblasts by Regulating the Death Receptor Pathway

Purpose

The study aimed to investigate the potential protective role of anthocyanin from Lycium ruthenicum Murr. in the Qaidam Basin against ultraviolet B (UVB)-induced apoptosis of human skin fibroblasts (HSFs).

Methods

HSFs cultured in vitro were randomly divided into a control group, UVB group, and anthocyanin groups (0.1, 0.5, and 1.0 mg/mL). HSFs in the UVB and anthocyanin groups were exposed to 30 mJ/cm² UVB to establish a photoaging model. Then, apoptosis rate, tumor necrosis factor-α (TNF-α), cysteinyl aspartate specific proteinase-3 (caspase-3), cysteinyl aspartate specific proteinase-7 (caspase-7), and survivin expression were evaluated.

Results

UVB irradiation can increase the apoptosis rate of HSFs and expression of TNF-α, caspase-7, and survivin. Anthocyanin pretreatment (0.1, 0.5, and 1.0 mg/mL) decreased UVB-induced apoptosis rate and TNF-α and caspase-7 expression and increased survivin expression. Compared with the control group, the apoptosis rate and expression of TNF-α, caspase-7, and survivin of anthocyanin groups in UVB-irradiated HSFs were high. Among the three doses of anthocyanin (0.1, 0.5, and 1.0 mg/mL) groups, the apoptosis rate and TNF-α expression of anthocyanin at 1.0 mg/mL were the lowest. There was no significant change in caspase-3 expression in each group.

Conclusion

Anthocyanin from Lycium ruthenicum Murr. in the Qaidam Basin could alleviate UVB-induced apoptosis by regulating the death receptor pathway.

Regenerative Medicine of Epithelia: Lessons From the Past and Future Goals

This article explores examples of successful and unsuccessful regenerative medicine on human epithelia. To evaluate the applications of the first regenerated tissues, the analysis of the past successes and failures addresses some pending issues and lay the groundwork for developing new therapies. Research should still be encouraged to fill the gap between pathologies, clinical applications and what regenerative medicine can attain with current knowledge.

Survivin in autoimmune diseases

Survivin is a protein functionally important for cell division, apoptosis, and possibly, for micro-RNA biogenesis. It is an established marker of malignant cell transformation. In non-malignant conditions, the unique properties of survivin make it indispensable for homeostasis of the immune system. Indeed, it is required for the innate and adaptive immune responses, controlling differentiation and maintenance of CD4⁺ and CD8⁺ memory T-cells, and in B cell maturation. Recently, survivin has emerged as an important player in the pathogenesis of autoimmune diseases. Under the conditions of unreserved inflammation, survivin enhances antigen presentation, maintains persistence of autoreactive cells, and supports production of autoantibodies. In this context, survivin takes its place as a diagnostic and prognostic marker in rheumatoid arthritis, psoriasis, systemic sclerosis and pulmonary arterial hypertension, neuropathology and multiple sclerosis, inflammatory bowel diseases and oral lichen planus. In this review, we summarise the knowledge about non-malignant properties of survivin and focus on its engagement in cellular and molecular pathology of autoimmune diseases. The review highlights utility of survivin measures for clinical applications. It provides rational for the survivin inhibiting strategies and presents results of recent reports on survivin inhibition in modern therapies of cancers and autoimmune diseases.

Notch Cooperates with Survivin to Maintain Stemness and to Stimulate Proliferation in Human Keratinocytes during Ageing

The Notch signaling pathway orchestrates cell fate by either inducing cell differentiation or maintaining cells in an undifferentiated state. This study aims to evaluate Notch expression and function in normal human keratinocytes. Notch1 is expressed in all epidermal layers, though to a different degree of intensity, with a dramatic decrease during ageing. Notch1 intracellular domain (N1ICD) levels are decreased during transit from keratinocyte stem cells (KSC) to transit amplifying (TA) cells, mimicking survivin expression in samples from donors of all ages. Calcium markedly reduces N1ICD levels in keratinocytes. N1ICD overexpression induces the up-regulation of survivin and the down-regulation of keratin 10 and involucrin, while increasing the S phase of the cell cycle. On the other hand, Notch1 inhibition (DAPT) dose-dependently decreases survivin, stimulates differentiation, and reduces keratinocyte proliferation in samples from donors of all ages. Silencing Notch downgrades survivin and increases keratin 10. In addition, Notch1 inhibition decreases survivin levels and proliferation both in KSC and TA cells. Finally, while survivin overexpression decreases keratinocyte differentiation and increases N1ICD expression both in KSC and TA cells, silencing survivin results in N1ICD down-regulation and an increase in differentiation markers. These results suggest that the Notch1/survivin crosstalk contributes to the maintenance of stemness in human keratinocytes.

Survivin gene promoter polymorphisms: Clinical significance and association with susceptibility to colon cancer

AIM: To investigate the clinical significance of survivin gene promoter polymorphisms and their association with susceptibility to colon cancer.

METHODS: The -31G/C, -241T/C, -625G/C and -644T/C single nucleotide polymorphisms in the survivin gene promoter region were genotyped in 217 colon cancer specimens and 198 normal people specimens by PCR-RFLP.

RESULTS: The frequency of the -31G/C locus containing the G allele (CG + GG) in colon cancer patients (60.8%) was significantly lower than that in the normal control group (60.8% vs 72.7%, P = 0.010, OR = 0.582, 95%CI: 0.385-0.882). The -31G/C site G variation was associated with tumor differentiation (P = 0.019), extent of tumor invasion (P = 0.008), and distant metastasis (P = 0.0008). Other three survivin polymorphisms had no significant differences between the colon cancer group and normal control group, and showed no significant correlation with tumor differentiation, tumor invasion, lymph node metastasis or tumor distant metastasis.

CONCLUSION: The -31G/C locus carrying the G allele significantly decreases susceptibility to colon cancer, and the G variant genotype is a protective factor against colon cancer.

Expression of nuclear survivin in normal skin and squamous cell carcinoma: a possible role in tumour invasion

Background:

Survivin is detected in few adult normal cells and it is highly expressed in cancer. Nuclear survivin facilitates cell cycle entry, whereas the mitochondrial pool protects cells from apoptosis. Survivin is overexpressed in keratinocyte stem cells (KSCs) and protects them from apoptosis.

Methods:

As KSCs are at the origin of squamous cell carcinoma (SCC), we evaluated survivin expression in normal and cancerous skin in vivo by immunohistochemistry and western blotting. HaCaT cells overexpressing survivin and wound-healing assay are used. Analysis of variance and Student's T-tests are used for statistical analysis.

Results:

Survivin is localised in both the cytoplasm and nucleus of normal adult and young keratinocytes. Nuclear survivin is detected in one every 10 of 11 basal keratinocytes. When present in suprabasal cells, nuclear survivin is coexpressed with K10 but not with K15 or p75-neurotrophin receptor (p75NTR), a transit amplifying cell marker. Nuclear, but not cytoplasmic, survivin expression markedly increases in actinic keratosis and in SCC in situ, as compared with normal epidermis, and it is highest in poorly differentiated SCC. In SCC tumours, nuclear survivin-positive cells are mainly K10/p75NTR-negative and K15-positive. In poorly differentiated tumours, survivin mostly localises in the deep infiltrating areas. When overexpressed in keratinocytes, survivin increases cell migration.

Conclusion:

High survivin expression and the subcellular localisation of survivin correlate with keratinocyte differentiation and are associated with undifferentiated and more invasive SCC phenotype.

Survivin: a dual player in healthy and diseased skin

Survivin belongs to the inhibitor of apoptosis (IAP) protein family, and, in addition to the antiapoptotic functions, it also regulates the cell cycle. The survivin gene generates five major isoforms with diverse and opposite functions. Survivin is highly expressed in cancer and in few normal adult tissues, including skin. It is mostly detected in the nucleus of keratinocyte stem cells (KSCs), but it is also expressed in melanocytes and fibroblasts. Survivin isoforms are differentially detected in subpopulations of human keratinocytes, exerting contrasting activities. Survivin has an important role in the regulation of cell cycle in keratinocytes, and it protects these cells from anoikis and UV-induced apoptosis. In melanoma, survivin is abundantly expressed, and its subcellular localization varies depending upon tumor thickness and invasiveness. Survivin overexpression has been shown in squamous cell carcinoma (SCC), and it is also involved in UVB-induced carcinogenesis. The presence of survivin both in the nucleus and in the cytoplasm throughout the epidermal layers of psoriatic lesions suggests the involvement of this protein in the keratinocyte alterations typical of this disease. Additional studies on the expression of survivin isoforms and their subcellular localization in relation to function will confirm the key role of survivin in the skin and will open the field to new therapeutic strategies for many cutaneous conditions.

Keratinocyte stem cells: friends and foes

Skin and its appendages provide a protective barrier against the assaults of the environment. To perform its role, epidermis undergoes an ongoing renewal through a balance of proliferation and differentiation/apoptosis called homeostasis. Keratinocyte stem cells reside in a special microenvironment called niche in basal epidermis, adult hair follicle, and sebaceous glands. While a definite marker has yet to be detected, data raised part in humans and part in the mouse system point to a critical role of stem and its progeny transit amplifying cells in epidermal homeostasis. Stem cells are protected from apoptosis and are long resident in adult epidermis. This renders them more prone to be the origin of skin cancer. In this review, we will outline the main features of adult stem cells in mouse and humans and discuss their fate in relation to differentiation, apoptosis, and cancer.

Clinical significance of survivin expression in hepatocellular carcinoma

AIM: To analyze the clinical significance of survivin expression in hepatocellular carcinoma (HCC).

METHODS: The expression of survivin was examined by immunohistochemistry and semiquantitative RT-PCR in 76 HCC specimens. The correlation between survivin expression and clinicopathological parameters in HCC were analyzed. Survival data were analyzed using the Kaplan-Meier method and multivariate Cox proportional hazards model.

RESULTS: The positive rate of survivin protein expression in HCC was 69.74% (53/76). The relative expression level of survivin mRNA in HCC tissue was significantly higher than that in tumor-adjacent normal tissue (0.782 ± 0.284 vs 0.251 ± 0.064, P < 0.01). The positive expression of survivin was correlated with HbsAg positivity, Edmondson grade, portal vein tumor thrombus (PVTT) and tumor number in HCC, but not with cirrhosis, alpha-fetoprotein level, tumor size and pseudocapsule. The 1, 2, 3-year survival rates were 62.0%, 40.7% and 19.0% in survivin-positive group and 85.9%, 59.3% and 50.8% in survivin-negative group, respectively (P = 0.025). Multivariate Cox regression analysis showed that the positive expression of survivin, PTVV and tumor number were significant prognostic factors for HCC, and the risk ratios were 1.702, 1.994 and 6.391, respectively.

CONCLUSION: Overexpression of survivin may be involved in the development and progression of HCC. Detection of survivin expression will be helpful in selecting high-risk HCC patients. Survivin may be a promising target for HCC therapy.