Somatic mutations of Fas (Apo-1/CD95) gene in cutaneous squamous cell carcinoma arising from a burn scar

Research Progress of Dihydroquercetin in the Treatment of Skin Diseases

Skin is a barrier to maintaining the stability of the human environment and preventing the invasion of pathogens. When skin tissue is exposed to the external environment, it will inevitably develop defects due to trauma, injury, burns, ulcers, surgery, and chronic diseases. Rapid skin repair is the key to reducing infection, relieving pain, and improving quality of life. Dihydroquercetin is a kind of flavonoid that has a wide range of pharmacological activities and can improve skin repair, skin inflammation, skin cancer, and so on. In this paper, the application of dihydroquercetin in medical dressings and the research progress in the treatment of skin-related diseases are reviewed, so as to provide reference for further developing dihydroquercetin as a drug for the treatment of skin diseases.

Effectiveness of artesunate combined with fractional CO2 laser in a hypertrophic scar model with underlying mechanism

BACKGROUND AND OBJECTIVES

Both artesunate and fractional CO2 laser have been proved effective in the treatment of hypertrophic scars, yet little data are available for the efficacy of artesunate combined with fractional CO2 laser. In order to assess the pre-clinical significance and the underlying mechanism of this combined treatment profile, we attempted to observe the effectiveness of this therapy in rabbit models through determining the expression of BMP-7 and Fas.

MATERIALS AND METHODS

Twenty-Four New Zealand white rabbits with established hypertrophic scar samples were randomly divided into control group and three treatment groups. Artesunate (20 μl/cm2) was injected into the rat's scar of artesunate and combination groups, while fractional CO2 laser (Combo mode, deep energy:10 mJ, super energy: 50 mJ) was applied to rats in fractional CO2 laser and combination groups at week 4 after model establishment. All rabbits underwent a total of 3 sessions of treatment once every 2 weeks. Histological and immunohistochemistry study, Western blot assay, cell viability, ELISA and RT-QPCR were performed at week 10 to observe the aspects of hypertrophic scar sample changes and expression of BMP-7 and Fas in the scar tissues.

RESULTS

Compared with control group, hypertrophic scars and the collagen fibers were significantly inhibited after treatment, and higher inhibition was seen in the samples in combination group compared to that in artesunate and fractional CO2 laser groups (P < 0.01). Meanwhile, BMP-7 and Fas expressions were both notably increased in all treatment groups, and upregulation of the two proteins was dominant in combination group (P < 0.01).

CONCLUSIONS

Artesunate combined with fractional CO2 laser is effective in hypertrophic scarring in this rabbit model. Our findings can serve as a potential alternative strategy to treatment of hypertrophic scar in clinical practice.

Verifying the outcomes of artesunate plus 595-nm PDL in hypertrophic scars via determining BMP-7 and Fas level in model rabbits

BACKGROUND AND OBJECTIVES

Single-use of artesunate (ART) or 595-nm pulsed-dye laser (PDL) has proven clinical efficacy in the treatment of hypertrophic scars (HSs), yet little research has been done on the combined use of ART and PDL. Bone morphogenetic protein-7 (BMP-7) and Fas are recognized to be two important proteins in reducing scar formation. This study was designed to observe the effect of ART combined with 595-nm PDL in the treatment of HS in rabbit models, and investigate the effect of such protocol on the expression of BMP-7 and Fas in rabbit models.

STUDY DESIGN/MATERIALS AND METHODS

Twenty-four New Zealand white rabbits were randomly divided into the control group, ART group, PDL group, and combined treatment (ART + PDL) group. ART was respectively applied to the ART group and combined treatment group. Treatment was once every 2-week for a total of three sessions for both groups. Animals in the PDL group were simply treated with 595-nm PDL. Then, hematoxylin & eosin and Van Gieson straining, immunohistochemical study, enzyme-linked immunosorbent assay (ELISA), Cell counting kit-8 test, western blot assay, and real-time polymerase chain reaction (RT-PCR) were carried out to observe the development of HS samples and expression of BMP-7 and Fas proteins in the sample tissues.

RESULTS

After treatment, the scar samples grew lower and flatter, which was particularly evident in the combined treatment group, with notably inhibited fibroblast and collagen compared to other groups (p < 0.001). Western blot assay and RT-PCR demonstrated that the expression of BMP-7 was most increased in scar samples treated by ART + PDL. BMP-7 level was correspondingly and notably upregulated in treatment groups, especially in the ART + PDL group. In addition, relevant expression of Fas was also higher after treatment, especially in the ART + PDL group compared to either ART or 595-nm PDL group. The difference was significant among groups (p < 0.001).

CONCLUSIONS

Combined use of ART and 595-nm PDL can inhibit HSs in rabbit models via inhibiting extra fibroblast and collagens. The potential mechanism may be involved in enhanced BMP-7 and Fas expression. Our observations may create an alternative therapeutic strategy for HSs in the clinic.

Impact of human CD95 mutations on cell death and autoimmunity: a model

CD95/Fas/APO-1 can trigger apoptotic as well as nonapoptotic pathways in immune cells. CD95 signaling in humans can be inhibited by several mechanisms, including mutations in the gene encoding CD95. CD95 mutations lead to autoimmune disorders, such as autoimmune lymphoproliferative syndrome (ALPS). Gaining further insight into the reported mutations of CD95 and resulting alterations of its signaling networks may provide further understanding of their presumed role in certain autoimmune diseases. For illustrative purposes and to better understand the potential outcomes of CD95 mutations, here we assign their positions to the recently determined 3D structures of human CD95. Based on this, we make certain predictions and speculate on the putative role of CD95 mutation defects in CD95-mediated signaling for certain autoimmune diseases.

Post-burn scar malignancy: 5-year management review and experience

The study spotlights a severe uncommon post‐burn complication, Marjolin's ulcer, in upper Egypt plastic and wound care centres. This problem is mainly related to inadequate medical care and awareness. No community or race is immune. The underlying malignant transformation mechanism remains unclear. The study aims, according to our experience, to review the prognostic factors through the management protocol of Marjolin's ulcers. This prospective study was conducted in the Aswan University Plastic & Burn surgery department in South Egypt between 2013 and 2020 and investigated 226 patients with chronic post‐burn ulceration. Nineteen cases were proved to have Marjolin's ulcer, and the other cases that had been excluded from being malignant went for reconstruction with split‐thickness skin graft with/without flap after adequate ulcer debridement. The surgical, oncologic, radiologic indications, and prognostic factors were reviewed according to our management outcome—the assessment with follow‐up period extended over 5 years. Histopathology of ulcers ranged among mild, moderate, and poorly differentiated squamous cell carcinoma. One scalp ulcer case showed basosquamous pathology. Most cases presented at age above 50, but no age was immune. The mean latent period was 29 years on average. The lesions' sites varied in their anatomic location where they involved the upper extremity, the scalp, and the lower extremity that had a predilection. Although surgical excision is the primary management line for tumour ablation, other factors may change the management course. During the follow‐up period, neoplasm recurrence in the form of lymph node enlargement and/or locoregional metastasis was detected in eight cases. Within 1 year after the intervention, six recurrent cases died, and two were saved. In addition to the case study, this paper reviewed the literature and provided our team a good experience in light of the NCCN protocol for non‐melanotic cutaneous carcinoma, although we suffered limited medical resources. It is concluded that early accurate diagnosis, low‐grade malignancy, and well‐planned individualised surgery with adjuvant radiotherapy were the best prognostic factors. The close follow‐up for an early sign of disease recurrence is paramount.

When Benign Becomes Cancer: Malignant Degeneration of Chronic Inflammation

Chronic inflammation, long implicated in the genesis of malignancy, is now understood to underlie an estimated 25% of all cancers. The most pertinent malignancies, to the plastic surgeon, associated with the degeneration of chronic inflammation include Marjolin's ulcer, breast implant-associated large cell lymphoma, radiation-induced sarcoma, and Kaposi's sarcoma. The cellular and genetic damage incurred by a prolonged inflammatory reaction is controlled by an increasingly understood cytokinetic system. Advances in understanding the chronic inflammatory cascade have yielded new therapeutics and therapeutic targets.

Pharmacological basis and new insights of taxifolin: A comprehensive review

The pharmacological characteristics of phytochemicals have prompted a lot of interest in their application in disease management. Due to the high incidence of cancer related mortality and morbidity throughout the world; experiments have concentrated on identifying the anticancer potential of natural substances. Many phytochemicals such as flavonoids and their derivatives produced from food offer a variety of new anti-cancer agents which prevent the cancer progression. Taxifolin, a unique bioactive flavonoid, is a dietary component that has grabbed the interest of dietitians and medicinal chemists due to its wide range of health benefits. It is a powerful antioxidant with a well-documented effect in the prevention of several malignancies in humans. Taxifolin has shown promising inhibitory activity against inflammation, malignancies, microbial infection, oxidative stress, cardiovascular disease, and liver disease. Anti-cancer activity has been shown to be relatively significant than other activities investigated in vitro and in vivo with a little or no side effects to the normal healthy cells. In summary this review offers the synopsis of recent breakthroughs in the use of taxifolin as a cancer treatment, as well as mechanisms of action. However, to develop a medicine for human usage, more study on pharmacokinetic profile, profound molecular mechanisms, and drug safety criteria should be conducted utilizing well-designed randomized clinical trials.

Coarse Grained Molecular Dynamic Simulations for the Study of TNF Receptor Family Members' Transmembrane Organization

The Tumor Necrosis Factor (TNF) and the TNF receptor (TNFR) superfamilies are composed of 19 ligands and 30 receptors, respectively. The oligomeric properties of ligands, both membrane bound and soluble, has been studied most. However, less is known about the oligomeric properties of TNFRs. Earlier reports identified the extracellular, membrane-distal, cysteine-rich domain as a pre-ligand assembly domain which stabilizes receptor dimers and/or trimers in the absence of ligand. Nevertheless, recent reports based on structural nuclear magnetic resonance (NMR) highlight the intrinsic role of the transmembrane domains to form dimers (p75NTR), trimers (Fas), or dimers of trimers (DR5). Thus, understanding the structural basis of transmembrane oligomerization may shed light on the mechanism for signal transduction and the impact of disease-associated mutations in this region. To this end, here we used an in silico coarse grained molecular dynamics approach with Martini force field to study TNFR transmembrane homotypic interactions. We have first validated this approach studying the three TNFR described by NMR (p75NTR, Fas, and DR5). We have simulated membrane patches composed of 36 helices of the same receptor equidistantly distributed in order to get unbiassed information on spontaneous proteins assemblies. Good agreement was found in the specific residues involved in homotypic interactions and we were able to observe dimers, trimers, and higher-order oligomers corresponding to those reported in NMR experiments. We have, applied this approach to study the assembly of disease-related mutations being able to assess their impact on oligomerization stability. In conclusion, our results showed the usefulness of coarse grained simulations with Martini force field to study in an unbiased manner higher order transmembrane oligomerization.

Characteristics of Marjolin's Ulcers in 21st Century: A Retrospective Study, Systematic Review, and Surgical Guideline Recommendation

Marjolin's ulcer is rare and aggressive malignancy. The objective was to conduct a review of Marjolin's ulcer cases to gain a better understanding and its management. A retrospective study of patients with Marjolin's ulcers at our hospital between 2010 and 2019 was conducted. For the systematic review, the electronic database of the National Library of Medicine was searched and articles published between 2000 and 2019 were included. A total of 14 patients were included in the retrospective study. Twelve patients were male. The mean age was 59.71 years. The latency period was 27.78 years. The most common malignancy was squamous cell carcinoma, and 71.43% had developed on the lower extremities. Well-differentiated squamous cell carcinomas occurred in 38.46% of the cases Rates of lymphovascular and perineural invasion were 30.77 and 23.08%, respectively. Results from the literature search yielded 80 case reports (91 cases) and 42 retrospective reviews (1216 cases). Most cases were male and the most common location was lower extremities. The latency period for the acute and chronic periods was 2.75 months and 20.75 years, respectively. The most common malignancy was squamous cell carcinoma (92.27% in the retrospective reviews) and 59.98% of the cases exhibited well-differentiation. Rates of regional lymph node involvement and distant metastases were 10.20 and 12.09%, respectively. Marjolin's ulcer in 21st century is not so rare. The most common is well differentiated squamous cell carcinoma. Early flap surgery or skin grafts for chronic ulcers or burn scars are recommended to reduce risk. Guideline for surgical management is established.

The Diversity and Similarity of Transmembrane Trimerization of TNF Receptors

Receptors in the tumor necrosis factor receptor superfamily (TNFRSF) regulate proliferation of immune cells or induce programmed cell death, and many of them are candidates for antibody-based immunotherapy. Previous studies on several death receptors in the TNFRSF including Fas, p75NTR, and DR5 showed that the transmembrane helix (TMH) of these receptors can specifically oligomerize and their oligomeric states have direct consequences on receptor activation, suggesting a much more active role of TMH in receptor signaling than previously appreciated. Here, we report the structure of the TMH of TNFR1, another well studied member of the TNFRSF, in neutral bicelles that mimic a lipid bilayer. We find that TNFR1 TMH forms a defined trimeric complex in bicelles, and no evidences of higher-order clustering of trimers have been detected. Unexpectedly, a conserved proline, which is critical for Fas TMH trimerization, does not appear to play an important role in TNFR1 TMH trimerization, which is instead mediated by a glycine near the middle of the TMH. Further, TNFR1 TMH trimer shows a larger hydrophobic core than that of Fas or DR5, with four layers of hydrophobic interaction along the threefold axis. Comparison of the TNFR1 TMH structure with that of Fas and DR5 reveals reassuring similarities that have functional implications but also significant structural diversity that warrants systematic investigation of TMH oligomerization property for other members of the TNFRSF.

Marjolin's Tumor Complicating Chronic Periprosthetic Infection of a Total Knee Arthroplasty

Marjolin's tumor is a term used to describe a malignancy developing in the setting of a chronic wound, infection, or other tissue subject to chronic inflammatory changes. These malignancies usually present after many years of chronicity, and can range from lower grade basal cell carcinomas to high-grade sarcomas. We present the case of a squamous cell carcinoma that developed within a chronic periprosthetic infection of a total knee arthroplasty of 7 years duration. The intra-articular location, association with an orthopaedic implant, and brief latency period are all unique features of this case.

Higher-Order Clustering of the Transmembrane Anchor of DR5 Drives Signaling

Receptor clustering on the cell membrane is critical in the signaling of many immunoreceptors, and this mechanism has previously been attributed to the extracellular and/or the intracellular interactions. Here, we report an unexpected finding that for death receptor 5 (DR5), a receptor in the tumor necrosis factor receptor superfamily, the transmembrane helix (TMH) alone in the receptor directly assembles a higher-order structure to drive signaling and that this structure is inhibited by the unliganded ectodomain. Nuclear magnetic resonance structure of the TMH in bicelles shows distinct trimerization and dimerization faces, allowing formation of dimer-trimer interaction networks. Single-TMH mutations that disrupt either trimerization or dimerization abolish ligand-induced receptor activation. Surprisingly, proteolytic removal of the DR5 ectodomain can fully activate downstream signaling in the absence of ligand. Our data suggest a receptor activation mechanism in which binding of ligand or antibodies to overcome the pre-ligand autoinhibition allows TMH clustering and thus signaling.

Transcriptional Analysis Reveals Evidence of Chronically Impeded ECM Turnover and Epithelium-to-Mesenchyme Transition in Scar Tissue Giving Rise to Marjolin's Ulcer

Marjolin's ulcer (MU) is an aggressive malignancy arising within chronic wounds. A major cause is unhealed burn injuries. This results in well-differentiated squamous cell carcinoma (SCC). This study aimed to elucidate transcriptional changes leading to malignancy by investigating differentially expressed genes in squamous cells present in a SCC compared with MU. MU tumor cells were isolated from histologically confirmed biopsy of SCC within an unhealed burn scar. Epithelial cells (ECs) adjacent to the tumor were co-isolated and a SCC cell line was commercially purchased. mRNA from all three samples was isolated and its expression was quantified using RNASeq. A threshold of log2fold change >2-fold in either direction was considered "differentially expressed." Gene expression analysis revealed distinct differences in gene expression in MU cells compared with EC (665 genes), EC and SCC (1673 genes). Enrichment analysis confirmed that pathways most affected included 1) elevation of genes associated with extracellular matrix organization/degradation, 2) activation of DNA damage, and 3) activation of cytokine signaling. Our analysis revealed two key insights about chronic wound microenvironment conducive to ulceration. First, in EC vs. MU comparison, downregulation of Collagen and Matrix metalloproteinase families suggests chronically impaired extracellular matrix turnover giving rise to a fibrotic microenvironment. Second, in SCC vs. MU comparison, dysregulation of cadherin-mediated cell-cell adhesions is suggestive of epithelial-to-mesenchymal transitions, similar to those during development. Acquisition of epithelial-to-mesenchymal transition may underlie the high metastatic rate in MU tumors. Taken together, this sheds light on mechanisms that underlie the divergent clinical features of these cutaneous cancers.

Marjolin's ulcer in chronic wounds - review of available literature

Marjolin's ulcer is a rare, aggressive skin cancer developing in scar tissue, chronic ulcers and areas affected by inflammations. Its incidence is estimated to range from 1% to 2% of all burn scars. It most frequently takes the form of squamous cell carcinoma which sometimes is diagnosed during examination of lesions developing in scars and hard-to-heal chronic wounds (pressure sores, leg ulcers). Therapeutic management of Marjolin's ulcer requires well-designed treatment plan to ensure optimal medical care and good quality of life for the patient. The high risk of metastases and damage to the structure of vitally important organs determines the need for early diagnosis and prompt surgical intervention with supplementary therapy. The purpose of the study was to examine etiopathogenesis of Marjolin's ulcer and principles of its treatment. The authors focused on the aspect of malignant degeneration in chronic wounds (leg ulcers, pressure sores) as a very rare, aggressive form of Marjolin's ulcer. A review of the available literature on the issue of Marjolin ulcers was conducted using the key words; Marjolin ulcers, pressure sore, chronic wound. Malignant degeneration in chronic wounds is a very rare aggressive form of Marjolin ulcer. Increased oncological alertness should be displayed by nursing and medical personnel taking care of patients with chronic wounds.

Mutations of Fas (APO-1/CD95) and p53 Genes in Nonmelanoma Skin Cancer

Background:

There is considerable evidence that apoptosis plays an important role in the pathogenesis of a wide variety of skin diseases. Apoptosis failure may ensure the survival of transformed cells prone to sustain further genetic damage and it plays an important part in the development of tumors. Genetic alterations of Fas and p53, with consequent inactivation of gene protein products, may be involved in transcriptional downregulation of Fas.

Objective:

We investigated Fas and its ligand expression in 30 cases of nonmelanoma skin cancer, 19 basal cell and 11 squamous cell carcinomas, and we also analyzed Fas and p53 status, in an attempt to detect putative alterations.

Method:

Fas and its ligand expression were evaluated by RT-PCR; the promoter and the entire coding region of Fas, and the coding exons 4–9 of p53 were investigated by polymerase chain reaction, single strand conformation polymorphism, and DNA sequencing.

Results:

Fas alterations were found in 3/19 (15.8%) basal cell and in 4/11 (36.4%) squamous cell carcinomas. Five out of 25 cases (3/19 basal cell and 2/11 squamous cell carcinomas) were p53-mutated, and in the majority of these cases there were concomitant mutations of the Fas gene (χ2 test; p = 0.035).

Conclusion:

Taken together, our findings highlight an involvement of the Fas/Fas-ligand system in the development of skin cancer, suggesting that the loss of its apoptotic function, in some cases linked to p53 alterations, may contribute to the self-maintenance of cancer cells.

Structural Basis and Functional Role of Intramembrane Trimerization of the Fas/CD95 Death Receptor

Fas (CD95, Apo-1, or TNFRSF6) is a prototypical apoptosis-inducing death receptor in the tumor necrosis factor receptor (TNFR) superfamily. While the extracellular domains of TNFRs form trimeric complexes with their ligands and the intracellular domains engage in higher-order oligomerization, the role of the transmembrane (TM) domains is unknown. We determined the NMR structures of mouse and human Fas TM domains in bicelles that mimic lipid bilayers. Surprisingly, these domains use proline motifs to create optimal packing in homotrimer assembly distinct from classical trimeric coiled-coils in solution. Cancer-associated and structure-based mutations in Fas TM disrupt trimerization in vitro and reduce apoptosis induction in vivo, indicating the essential role of intramembrane trimerization in receptor activity. Our data suggest that the structures represent the signaling-active conformation of Fas TM, which appears to be different from the pre-ligand conformation. Analysis of other TNFR sequences suggests proline-containing sequences as common motifs for receptor TM trimerization.

Dhoti cancer: a waistline skin cancer with review of literature

Skin cancers account for less than 1 % of all malignancies in India. Squamous cell carcinomas occurring over the waistline due to tying of cotton cloth called dhoti in males and sarees in females are predominantly seen in traditional Indian population. On wearing of these clothes for years, there is a constant irritation which produces depigmentation, glazing of the skin, acanthosis, scar formation, and later on malignant transformation. Presenting a case of a 65-year-old male with 7 × 5 cm ulceroproliferative growth over the right waistline with a history of prolonged use of dhoti. Wide local excision of the growth with 2-cm margin and primary closure of wound by mobilizing the skin was carried out. Histopathology showed well-differentiated squamous cell carcinoma. The patient is clinically disease free after postoperative follow-up of 1 year.

Clinical characteristics and therapeutic analysis of 51 patients with Marjolin's ulcers

Marjolin's ulcers, which are epidermoid carcinomas arising on non-healing scar tissue, may be of various pathological types, including squamous cell carcinoma. The pathogenesis of squamous cell carcinoma arising in an ulcer differs from that of the primary cutaneous squamous cell carcinoma. This squamous cell carcinoma is aggressive in nature, and has a high rate of metastasis. Between January 2001 and September 2013, 51 patients with Marjolin's ulcers were admitted to the Departments of Plastic Surgery of the Affiliated Foshan Hospital and the Second Affiliated Hospital of Sun Yat-sen University. The ulcers included 43 cases of squamous cell carcinoma, six of melanoma, one of basal cell carcinoma and one of epithelioid sarcoma. The clinical data of these patients were retrospectively analyzed. Patients were followed until mortality. Among the patients with squamous cell carcinoma, 30.23% exhibited sentinel lymph node metastasis and 11.63% had distant metastasis. Among the patients with melanoma, 66.67% had sentinel lymph node metastasis and 33.33% had distant metastasis. Sentinel lymph node metastasis was successfully detected in 11 patients with Marjolin's ulcer using ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography and B-mode ultrasound guided biopsy. Squamous cell carcinoma was often treated by extended resection and skin grafting or skin flap repair. Patients with deep, aggressive squamous cell carcinoma of an extremity and sentinel lymph node metastasis underwent amputation and lymph node dissection. This treatment was also used for melanoma type Marjolin's ulcers.

An Australian cohort of 210 patients with multiple invasive squamous cell carcinomas: risk factors and associated increased risk of melanoma and internal malignancies

BACKGROUND

Patients with a history of non-melanoma skin cancer (NMSC) have a 50% risk of developing subsequent NMSC.(13) Currently there are limited data on the association between multiple squamous cell carcinomas (SCC) and the risk of other cancers, including melanomas.

OBJECTIVE

To assess the risk factors in a cohort of 210 Australians with a history of multiple invasive SCC, focusing on the association between multiple SCC and other cancers.

METHODS

Data were collected from patients of a private practice in south-east Queensland.

RESULTS

A fair complexion and childhood sun exposure were found to be common in this cohort. Approximately half the patients who had their first SCC at or before the age of 30 years subsequently developed a melanoma. There was also an increased risk of internal cancer, prostate cancer being the commonest, followed by bowel and breast cancer.

CONCLUSION

Patients with a history of multiple invasive SCC should be aware of their increased risk of future NMSC and of melanomas. The results of thisstudy suggest such patients and their care providers should also consider an appropriate screening for internal malignancies.

A rare case of synchronous saree cancer

Skin cancers are rather uncommon malignancies comprising less than 1% of all the cancers in India. Saree cancer is a rare type of squamous cell carcinoma (SCC). Saree and dhoti are traditional male and female costumes respectively, which is unique to the Indian subcontinent. Constant wear of this clothing tightly around the waist results in changes in pigmentation and scaling of the skin, acanthosis, scar and ulceration and subsequent, gradual malignant changes. The process of repeated trauma over a long time and consequent interference with the healing process may rationalise the reason for malignant transformation. Few papers have been published on saree cancer, in main stream medical journals. We are presenting a rare case of saree cancer in a 68-year-old woman, with two distant bilateral ulceroproliferative growths in loin (Synchronous), along the waistline, which showed well-differentiated SCC on biopsy. Wide excision with rhomboid transposition flap was done bilaterally.

A Retrospective Study of Marjolin's Ulcer Over an Eleven Year Period

Background:

Marjolin's ulcer is a rare aggressive cutaneous malignancy occurring in previously occurred wounds. The most common aetiology is a burn wound involving extremities and squamous cell carcinoma is the most common variant.

Materials and Methods:

A retrospective analyses of medical records of patients treated in a single unit with a diagnosis of Marjolin's ulcer was performed.

Results:

During the study period, 14 patients were treated. Four patients had lymph node metastases and one had pulmonary metastases at the time of presentation. Seven patients underwent wide excision with reconstruction and seven underwent amputation or disarticulation because of advanced malignancy. During the follow up two patients developed local recurrence and one developed pulmonary metastases. Both the patients with pulmonary metastases had Marjolin's ulcer of trunk.

Conclusion:

Marjolin's ulcer occurs more commonly in the extremities. Distant metastases occur commonly in patients with ulcers on the of trunk.

CD95-mediated cell signaling in cancer: mutations and post-translational modulations

Apoptosis has emerged as a fundamental process important in tissue homeostasis, immune response, and during development. CD95 (also known as Fas), a member of the tumor necrosis factor receptor (TNF-R) superfamily, has been initially cloned as a death receptor. Its cognate ligand, CD95L, is mainly found at the plasma membrane of activated T-lymphocytes and natural killer cells where it contributes to the elimination of transformed and infected cells. According to its implication in the immune homeostasis and immune surveillance, and since several malignant cells of various histological origins exhibit loss-of-function mutations, which cause resistance towards the CD95-mediated apoptotic signal, CD95 has been classified as a tumor suppressor gene. Nevertheless, this assumption has been recently challenged, as in certain pathophysiological contexts, CD95 engagement transmits non-apoptotic signals that promote inflammation, carcinogenesis or liver/peripheral nerve regeneration. The focus of this review is to discuss these apparent contradictions of the known function(s) of CD95.

Marjolin's ulcers at a university teaching hospital in Northwestern Tanzania: a retrospective review of 56 cases

Background

Marjolin's ulcer is a rare but highly aggressive squamous cell cancer that is most often associated with chronic burn wounds. Although many individual case reports exist, no comprehensive evaluation of Marjolin's ulcer patients has been conducted in our setting. This study was conducted to describe the clinicopathological presentation and treatment outcome of this condition in our local setting and to identify predictors of outcome.

Methods

This was a retrospective study of histologically confirmed cases of Marjolin's ulcer seen at Bugando Medical Centre over a period of 10-years between January 2001 and December 2010. Data were retrieved from patients' files and analyzed using SPSS computer software version 15.0

Results

A total of 56 patients were studied. Male to female ratio was 2.1:1. Burn scars (89.3%) were the most common causative lesions of Marjolin's ulcer. The mean latent period between original injury and diagnosis of Marjolin's ulcer was 11.34 ± 6.14 years. Only 12.0% of the reported cases were grafted at the time of injury (P < 0.00). Most patients (48.2%) presented between one and five years of onset of illness. The lower limb (42.9%) was the most frequent site for Marjolin's ulcers. The median tumor size at presentation was 8 cm and the vast majority of patients (85.7%) presented with large tumors of ≥ 5 cm in diameter. Lymph node metastasis at the time of diagnosis was recorded in 32.1% of cases and distant metastasis accounted for 26.9% of cases. Squamous cell carcinoma (91.1%) was the most common histopathological type. Wide local excision was the most common surgical procedure performed in 80.8% of cases. Post-operative complication rate was 32.1% of which surgical site infection was the most common complication in 38.9% of patients. Local recurrence was noted in 33.3% of cases who were treated surgically. The mean length of hospital stay for in-patients was 7.9 ± 2.3 days. Mortality rate was 7.1%. According to multivariate logistic regression analysis, stage and grade of the tumor and presence of local recurrence were the main predictors of death (P < 0.001).

Conclusion

Marjolin's ulcers are not rare in our environment and commonly occur in burn scars that were not skin grafted and were left to heal secondarily. A high index of suspicion is required in the management of chronic non-healing ulcers and all suspected lesions should be biopsed. Early recognition and aggressive treatment of Marjolin's ulcers and close follow-up are urgently needed to improve outcomes in our environment.

Management of Marjolin's ulcer in a chronic pressure sore secondary to paraplegia: a radical surgical solution

Marjolin's ulcer refers to malignant degeneration in a chronic wound. Although originally described in an area of burns scar, many other chronic wounds such as osteomyelitis sinus tracts, venous stasis ulcers and chronic pressure sores have the potential to undergo malignant transformation. We present an interesting case of malignant degeneration in a male paraplegic patient with chronic sacral and ischial pressure sores. By discussing our radical surgical solution to this problem, we aim to highlight the importance of prompt diagnosis.

Skin cancer arising in scars: a systematic review

BACKGROUND

Despite numerous case reports, epidemiologic evidence regarding true rate of skin cancer in scars of any etiology is sparse.

METHODS

Systematic literature review of all published epidemiologic studies on skin cancer in scar tissue from surgery, ulcers, or burns using citation databases and manual review.

RESULTS

There were no epidemiologic data to quantify risk of skin cancer in surgical scars or chronic ulcers. Two eligible cohort studies were identified, from Denmark and Sweden, in which skin cancers in 16, 903 and 37,095 burn patients, respectively, were ascertained through cancer registry follow-up. Each reported standardized incidence ratios (SIRs) for skin cancer types on any site that were uniformly less than unity compared with the general population. Only the Danish cohort assessed skin cancers specifically on past burn injury sites and found a burn-site-specific SIR of 1.2 (95% confidence interval (CI)=0.4-2.7) for squamous cell carcinoma (SCC), 0.7 (95% CI=0.4-1.1) for basal cell carcinoma, and 0.3 (95% CI=0.0-1.2) for melanoma.

CONCLUSIONS

Available epidemiologic data suggest that burn patients are not at higher risk of skin cancers in general, although a modest excess of SCC in burn scars cannot be excluded, nor can excess risk with longer follow-up. Risk of skin cancer in scars other than burn scars has not been investigated epidemiologically.

The critical protein interactions and structures that elicit growth deregulation in cancer and viral replication

One of the greatest challenges in biomedicine is to define the critical targets and network interactions that are subverted to elicit growth deregulation in human cells. Understanding and developing rational treatments for cancer requires a definition of the key molecular targets and how they interact to elicit the complex growth deregulation phenotype. Viral proteins provide discerning and powerful probes to understand both how cells work and how they can be manipulated using a minimal number of components. The small DNA viruses have evolved to target inherent weaknesses in cellular protein interaction networks to hijack the cellular DNA and protein replication machinery. In the battle to escape the inevitability of senescence and programmed cell death, cancers have converged on similar mechanisms, through the acquisition and selection of somatic mutations that drive unchecked cellular replication in tumors. Understanding the dynamic mechanisms through which a minimal number of viral proteins promote host cells to undergo unscheduled and pathological replication is a powerful strategy to identify critical targets that are also disrupted in cancer. Viruses can therefore be used as tools to probe the system-wide protein-protein interactions and structures that drive growth deregulation in human cells. Ultimately this can provide a path for developing system context-dependent therapeutics. This review will describe ongoing experimental approaches using viruses to study pathways deregulated in cancer, with a particular focus on viral cellular protein-protein interactions and structures.

Current concepts in the management of Marjolin's ulcers: outcomes from a standardized treatment protocol in 16 cases

Marjolin's ulcer is a malignant lesion observed in chronic wounds and in areas where the integrity of the skin is compromised because of any one of several reasons. The aim of this study was to define etiology, topography, and histopathology for Marjolin's ulcer and its surgical management. Sixteen cases were diagnosed and treated as Marjolin's ulcers. The mean age was 57.1 years (range, 32-85 years) and 15 of the patients (93.75%) had history of ulcer of 30 years or more. In 10 cases (62.5%), Marjolin's ulcer occurred after a flame burn and in 6 cases (37.5%) after a scalding burn injury. In six cases (37.5%), there was history of chronic trauma due to contact with the clothing. Primary lesions were at the leg, gluteal region, thigh, scalp, trunk, and hand in four (25%), three (18.7%), two (12.5%), two (12.5%), three (18.7%), and two (12.5%) cases, respectively. Amputation was carried out to treat two cases, and repair of the defects with partial-thickness skin grafting was performed in 14 cases after tumor resection on the skin. Superficial inguinal lymph node dissections were performed in four cases with tumor in the thigh and a positive inguinal lymph node. Squamous cell carcinoma was diagnosed in 14 cases (87.5%) and basal cell carcinoma in two cases (12.5%) postoperatively. The authors conclude that diagnosis and surgical planning based on the recent literature must be carried out even more intensively to improve the prognosis of Marjolin's ulcer.

Marjolin's ulcers: theories, prognostic factors and their peculiarities in spina bifida patients

Background

Due to improved care, more and more children born with spina bifida in rural Kenya are surviving into adulthood. This improved survival has led to significant challenges in their lifestyles, especially the need to ensure pressure ulcer prevention and treatment. Malignant degeneration of pressure ulcers in spina bifida patients is very rare. The author describes the clinical presentation of two pressure ulcer carcinomas that are at variance from classical descriptions.

Materials and methods

An internet/Medline/PubMed search of English literature for theories on Marjolin's ulcer evolution and prognostic features of Marjolin's ulcers was performed.

A chart review of two young adults with spina bifida who had presented to the author's hospital between 2004 and August 2010 with chronic pressure ulcers found to be Marjolin's ulcers on histo-pathological examination was performed, and the clinical features are reported.

Results

The two ulcers appeared clinically benign: one was a deep ulcer, while the other was shallow; both had normal, benign-appearing edges, and a foul smelling discharge. The two ulcers were surrounded by induration and multiple communicating sinuses, with no evidence of chronic osteomyelitis. The internet search revealed a total of nine theories on Marjolin's ulcer development, as well as seven clinical and four histological prognostic features.

Discussion

The multifactorial theory, a coalescence of a number of proposed theories, best explains the evolution of Marjolin's ulcers. Poor prognostic features include pressure ulcer carcinomas, lesions and location in the lower limbs/trunks, all present in the two patients making their prognosis dim: this is despite the surgical margins being clear of tumor. Benign appearance, induration and presence of multiple communicating sinuses are features that have not been previously described as presenting features of pressure ulcers carcinomas.

Conclusion

There is need for spina bifida patients and their guardians/caretakers to receive a close follow-up throughout life; health education focused on pressure ulcer prevention as well as early treatment of pressure ulcers when they occur, will avert the development of Marjolin's ulcers, and save lives.

Fas and FasL polymorphisms are not associated with acute myeloid leukemia risk in Koreans

Fas and Fas ligand (FasL) polymorphisms in the promoter regions influence transcriptional activities. The interaction of these two genes plays a crucial role in apoptotic cell death regulation. They have been associated with esophageal, lung, uterine cervical, and urinary bladder cancers in human. We performed a case-control study to investigate the association between Fas and FasL polymorphisms and acute myeloid leukemia (AML) risk. Fas−1377G>A (rs2234767), −670T>C (rs1800682), and FasL−844T>C (rs763110) polymorphisms in 592 AML patients and 858 healthy controls were genotyped and tested for associations between polymorphisms and AML risk. There were no significant differences in genotypic and haplotypic distributions and gene-gene interaction between patients and controls in the overall analysis (p>0.05). These results suggested that polymorphisms of Fas and FasL genes were not associated with AML risk in the Korean population.

Marjolin's ulcer in an amputation stump

Marjolin's ulcers are uncommon malignancies arising from previously traumatized, chronically inflamed or scarred skin. They are usually squamous cell carcinomas and arise most often after burns, and they may present decades after the original insult. Metastases are observed more often than in other cutaneous squamous cell carcinomas. Marjolin's ulcers may occur on stumps in patients using prostheses, in this situation the diagnosis may be delayed because of the false assumption that the ulcer is caused by an ill fitting prosthesis. A case of Marjolin's ulcer is presented occurring on a lower limb stump 68 years following from a burn in infancy. The cause, diagnosis, treatment, and prognosis of Marjolin's ulcer are discussed.

DNA methylation-mediated nucleosome dynamics and oncogenic Ras signaling: insights from FAS, FAS ligand and RASSF1A

Cytosine methylation at the 5-carbon position is the only known stable base modification found in the mammalian genome. The organization and modification of chromatin is a key factor in programming gene expression patterns. Recent findings suggest that DNA methylation at the junction of transcription initiation and elongation plays a critical role in suppression of transcription. This effect is mechanistically mediated by the state of chromatin modification. DNA methylation attracts binding of methyl-CpG-binding domain proteins that trigger repression of transcription, whereas DNA demethylation facilitates transcription activation. Understanding the rules that guide differential gene expression, as well as transcription dynamics and transcript abundance, has proven to be a taxing problem for molecular biologists and oncologists alike. The use of novel molecular modeling methods is providing exciting insights into the challenging problem of how methylation mediates chromatin dynamics. New data implicate lipid rafts as the coordinators of signals emanating from the cell membrane and are converging on the mechanisms linking DNA methylation and chromatin dynamics. This review focuses on some of these recent advances and uses lipid-raft-facilitated Ras signaling as a paradigm for understanding DNA methylation, chromatin dynamics and apoptosis.

Resistance to FasL and tumor necrosis factor-related apoptosis-inducing ligand-mediated apoptosis in Sezary syndrome T-cells associated with impaired death receptor and FLICE-inhibitory protein expression

Because of the low proliferative potential of tumor cells in patients with Sézary syndrome (SzS), their accumulation has been suggested to be due to defective regulation of apoptosis. We analyzed the sensitivity to soluble Fas-ligand (FasL) and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), 2 members of the TNF superfamily in peripheral blood leukocytes (PBL) from patients with SzS. Compared with healthy donors, CD4(+) cells from patients with SzS were completely resistant to FasL in 9 of 16 cases. Of these 9 FasL-resistant cases, 4 revealed a loss in Fas (CD95) expression, whereas the remaining 5 exhibited normal or enhanced Fas expression. In the latter 5 cases, the apoptosis inhibitor cFLIP was overexpressed in CD4(+)/CD26(-) tumor cells compared with CD4(+)/CD26(-) cells from Fas-expressing FasL-sensitive patients and healthy donors. Furthermore, resistance to TRAIL and tumor cell-restricted loss of TRAIL-receptor 2 were observed in 16 of 16 SzS PBLs. It is noteworthy that resistance to FasL could be overcome by the use of a hexameric FasL or upon exposure of SzS cells to interferon-alpha (IFN-alpha) or IFN-gamma, the latter by an increase of Fas expression. Our data on primary SzS lymphocytes reveal frequent resistance to apoptosis induced by FasL and TRAIL, which may contribute to their accumulation in patients with SzS and be relevant at a therapeutic level.

Dissecting lipid raft facilitated cell signaling pathways in cancer

Cancer is one of the most devastating disorders in our lives. Higher rate of proliferation than death of cells is one of the essential factors for development of cancer. The dynamicity of cell membrane plays some vital roles in cell survival and cell death, including protection, endocytosis, signaling, and increases in mechanical stability during cell division, as well as decrease of shear forces during separation of two cells after division, and cell separation from tissues for cancer metastasis. Within the membrane, there are specialized domains, known as lipid rafts. A raft can coordinate various signaling pathways. Recent data on the proteomics of lipid rafts/caveolae have highlighted the enigmatic role of various signaling proteins in cancer development. Analysis of these data of raft proteome from various tumors, cancer tissues, and cell lines cultured without and with therapeutic agents, as well as from model rafts revealed that there may be two subsets of raft assemblage in cell membrane. One subset of raft is enriched with cholesterol-sphingomyeline-ganglioside-cav-1/Src/EGFR (hereafter, "chol-raft") that is involved in normal cell signaling, and when dysregulated promotes cell transformation and tumor progression; another subset of raft is enriched with ceramide-sphingomyeline-ganglioside-FAS/Ezrin (hereafter, "cer-raft") that generally promotes apoptosis. In view of this, and to focus insight into the cancer cell physiology caused by the lipid rafts mediated signals and their receptors, and the downstream transmitters, either proliferative (for example, EGF and EGFR) or death-inducing (for example, FASL and FAS), and the precise roles of some therapeutic drugs and endogenous acid sphingomylenase in this scenario in in situ transformation of "chol-raft" into "cer-raft" are summarized and discussed in this contribution.

Proteomic investigation of human burn wounds by 2D-difference gel electrophoresis and mass spectrometry

BACKGROUND

In humans, thermal cutaneous injury represents a serious traumatic event that induces a host of dynamic alterations. Unfortunately the molecular mechanisms that underlie these serious perturbations remain poorly understood. We applied a global analysis method to identify dynamically changing proteins within the burn environment, which could eventually become biomarkers or targets for treatment.

MATERIALS AND METHODS

Protein extracts of normal/unwounded skin and burn wounds were assayed by 2D-difference gel electrophoresis (DIGE), a proteomic technology by which abundance levels of intact proteins (including isoforms) were simultaneously quantified from multiple samples with statistical confidence. Through unsupervised multivariate principal component analysis, protein expression patterns from individual samples were appropriately clustered into their correct temporal healing periods grouped into postburn periods of 1-3 days, 4-6 days, or 7-10 days after injury. Forty-six proteins were subsequently selected for identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

RESULTS

Proteins identified with differential temporal patterns of expression included predictable cytoskeletal proteins such as vimentin, and keratins 1, 5, 6, 16, and 17. Other candidate proteins with potential involvement in healing included heat shock protein 90, members of the serpin family (Serpin B1, SCCA1 and -2), haptoglobin, gelsolin, eIF4A1, IQGAP1, and translationally controlled tumor protein.

CONCLUSIONS

We have used the combined technique, DIGE/mass spectrometry, to capture new insights into cutaneous responses to burn trauma and subsequent processes of early wound healing in humans. This pilot study provides a proteomic snapshot of temporal events that can be used to weave together the interconnected processes that define the response to serious cutaneous injury.

Cell suicide and caspases

Programmed cell death or apoptosis is a well regulated physiological form of cellular autodestruction. It plays an essential role in embryonic development, homeostasis, remodeling, surveillance, and host defense mechanisms. Conversely dysregulation of apoptosis, resulting in either too less or excessive cell death is implicated in pathogenesis of stroke, myocardial infarction, neurodegenerative diseases, cancer and autoimmmune disorders. Apoptosis is coordinated by a family of cysteine proteinases called caspases, which dismantle the cell by targeting panoply of proteins. The mammalian caspase family contains 14 members, a subset participates in cellular demise and the remaining are involved in the processing of pro-inflammatory cytokines. We have tried to develop a simplified picture of basic apoptotic mechanisms on the basis of recent insights into the area.

Úlcera de Marjolin: carcinoma sobre cicatriz por quemadura

The term Marjolin's ulcer means the malignant transformation of chronic ulcers, sinus tract and burn scars. The most frequently produced neoplasm is squamous cell carcinoma. The pathogeny is unknown, involving mutations in the Fas gene. Main therapeutic management are consist of prophylactic measures, avoiding repeated traumas and prolonged cure periods. We present the case of a 48-year-old male with squamous cell carcinoma on the old burn scar of legs that evolved favorably after excision.

Tumor suppressor gene identification using retroviral insertional mutagenesis in Blm-deficient mice

Retroviral insertional mutagenesis preferentially identifies oncogenes rather than tumor suppressor (TS) genes, presumably because a single retroviral-induced mutation is sufficient to activate an oncogene and initiate a tumor, whereas two mutations are needed to inactivate a TS gene. Here we show that TS genes can be identified by insertional mutagenesis when the screens are performed in Blm-deficient backgrounds. Blm-deficient mice, like Bloom syndrome patients, have increased frequencies of mitotic recombination owing to a mutation in the RecQ protein-like-3 helicase gene. This increased mitotic recombination increases the likelihood that an insertional mutation in one allele of a TS gene will become homozygoused by non-sister chromatid exchange and the homozygosity of the insertion provides a marker for identifying the TS gene. We also show that known as well as novel TS genes can be identified by insertional mutagenesis in Blm-deficient mice and identify two JmjC family proteins that contribute to genome stability in species as evolutionarily diverse as mammals and Caenorhabditis elegans.

Squamous Cell Carcinoma Developing on Burn Scar

BACKGROUND

It is estimated that 2% of burn scars undergo malignant transformation. Squamous cell carcinoma (SCC) is the most common type of cancer that develops.

MATERIALS AND METHODS

We report a retrospective study, which consists of 510 patients who have 570 cases of tumors of SCC. We examined SCCs developing on burn scars retrospectively among 570 cases, and we found that 36 cases had SCC developing on burn scars. The records of those 36 cases were analyzed in terms of age, sex, latent period between burn and carcinoma, anatomic localization of the carcinoma, and the presence of metastases. These findings were compared with the SCC group that did not have burn history.

RESULTS

The number of SCC developing on burn scars among the 570 cases was 36 (6.31%), 15 of which were women (41.66%) and 21 were men (58.33%). The average age was 46.77 years. The average latent period between burn and the development of carcinoma was found to be 32.22 years. It should be mentioned that the burn scar carcinoma group was younger. In addition, burn scar carcinoma was more likely to localize on lower extremities and metastasize (P<0.001).

CONCLUSION

Having high aggressive features, the suspicion of development of SCC in burn scar should be kept in mind, so patients with burn scar must be followed periodically.

A polymorphism in FAS gene promoter associated with increased risk of nasopharyngeal carcinoma and correlated with anti-nuclear autoantibodies induction

Loss of FAS (CD95) expression is a common feature of malignant transformation, which has been related to loss of epithelial cell differentiation and loss of sensitivity to apoptosis. We investigated the potential association between FAS promoter polymorphism and the genetic susceptibility to the Epstein-Barr virus (EBV)-related nasopharyngeal carcinoma. The in vivo functional significance of the FAS polymorphism was investigated by assessing the correlation between FAS genotypes and the presence of autoantibodies to cytoskeleton and nuclear antigens frequently detected in nasopharyngeal carcinoma. We determined the FAS polymorphism distributions by RFLP-PCR in 170 patients with nasopharyngeal carcinoma and in 224 sex and age-matched controls. We used ELISA and the immunofluorescence analysis to characterize the presence of IgG autoantibodies to the cytoskeleton and nuclear proteins in patients' sera. A significantly increased risk of nasopharyngeal carcinoma was associated with heterozygote FAS-A/G (OR=2.00, P=0.001) and homozygote FAS-G/G (OR=3.19, P=0.0001) variants. The increased frequency of FAS-G/G genotype is correlated with the presence of anti-nuclear autoantibodies in patients with nasopharyngeal carcinoma (P=0.0298). Our results demonstrated that FAS promoter polymorphism was significantly associated with the nasopharyngeal carcinoma in Tunisians. The anti-nuclear autoantibodies induction was also found to be related to FAS polymorphism. The FAS promoter polymorphism associated not only with the increased risk of nasopharyngeal carcinoma in Tunisians but also with immune response deregulation observed in this cancer.

Burn scar neoplasms: a literature review and statistical analysis

BACKGROUND

Although squamous cell carcinoma (SCC) is the most common burn scar neoplasm, other neoplasms have also been reported.

OBJECTIVE

To compile the burn scar neoplasm cases in the literature and to analyze their frequency and demographic characteristics.

MATERIALS AND METHODS

Cases were obtained through literature searches.

RESULTS

There were 412 cases gleaned from 146 articles between 1923 and 2004. Seventy-one percent (293) of the tumors were squamous cell carcinoma, 12% (48) were basal cell carcinoma (BCC), 6% (23) were melanoma, 5% (21) were sarcoma, 4% (16) were other neoplasms, 1% (6) were squamo-basal cell carcinoma, and 1% (5) squamous cell-melanoma. The mean age at tumor diagnosis was 50 years, the mean age at the time of burn injury was 20 years, the mean latency interval was 31 years. Only 5% of the reported cases were excised and grafted at the time of injury (p<0.001). BCC occurred at a significantly later age compared to SCC and sarcoma groups (p<0.02) and had a shorter latency period compared to SCC and sarcoma groups (p<0.004) and melanoma (p<0.008). Local recurrence was present in 16% of the cases, while regional lymph node involvement was seen in 22% of the cases and distant metastases was present in 14% of the patients. The mortality rate was 21%.

CONCLUSIONS

Although the main burn scar neoplasm was SCC, other neoplasms contributed to the morbidity and mortality of burn patients. Excision and grafting of deep burns, and close follow-up of non-healing ulcerated burn scars is essential for the prevention and early detection of burn scar neoplasms.

Does CD95 have tumor promoting activities?

CD95 (APO-1/Fas) is an important inducer of the extrinsic apoptosis signaling pathway and therapy induced apoptosis of many tumor cells has been linked to the activity of CD95. Changes in the expression of CD95 and/or its ligand CD95L are frequently found in human cancer. The downregulation or mutation of CD95 has been proposed as a mechanism by which cancer cells avoid destruction by the immune system through reduced apoptosis sensitivity. CD95 has therefore been viewed as a tumor suppressor. Furthermore, increased CD95L concentration in tumor patients has been linked to tumor cells killing infiltrating lymphocytes in a process called "the tumor counter-attack". Recent data have illuminated unknown activities of CD95 in tumor cells with downregulated or mutated CD95 in the presence of increased CD95L. Under these conditions the stimulation of CD95 signals nonapoptotic pathways, activating NF-kappaB and MAP kinases for example, which may result in the induction of tumorigenic or prosurvival genes. A new model of CD95 functions is proposed in which CD95 is converted from a tumor suppressor to a tumor promotor by a single point mutation in one of the CD95 alleles, a situation frequently found in advanced human cancer, resulting in apoptosis resistance and activation of tumorigenic pathways.