Biomedical subjects
Publications and source records attributed to E C Benton.
We describe a male patient with Rothmund-Thomson syndrome (RTS) given postoperative radiotherapy for squamous carcinoma of the tongue. This was well tolerated. This is only the second reported case of oral cancer and radiotherapy in RTS.
In this study we have determined the ability of IGF-1 to protect cardiac fibroblasts against osmotic-induced apoptosis and investigated the potential mechanism(s) underlying this protection. Treatment with IGF-1 (1-100 ng/ml) promoted a dose dependent increase in cell survival against osmotic cell death. Both Akt and ERK1/2 were rapidly phosphorylated by IGF-1 and blocked by wortmannin and PD98059, inhibitors of their upstream activators respectively. However, IGF-1-induced protection was mediated via a wortmannin-dependent but PD98059-independent pathway as determined by cell survival assay suggesting a role of PI3-K/Akt. Furthermore, IGF-1 appeared to reduce the activation of a number of early components in the apoptotic pathway in a wortmannin dependent manner including the osmotic stress-induced perturbation in mitochondrial membrane potential, cleavage and activation of caspase-3 and DNA fragmentation. Thus, the results suggest that IGF-1 regulates osmotic stress-induced apoptosis via the activation of the PI3-K/Akt pathway at a point upstream of the mitochondria and caspase-3.
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We report the cases of two patients who developed generalized pustular psoriasis on the withdrawal of oral Cyclosporin treatment for persistent palmoplantar pustulosis. This complication does not appear to have been reported previously.
Linear scleroderma 'en coup de sabre' is characterized by atrophy and furrowing of the skin of the frontoparietal region. In most cases it occurs as a single, paramedian line that may be associated with hypoplasia of underlying structures and hemiatrophy of the face. Rarely, lesions form two lines, either both on the same side or bilaterally. We describe an 18-year-old male with an unusual tri-linear pattern of scleroderma 'en coup de sabre' following Blaschko's lines.
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Keratosis follicularis spinulosa decalvans (KFSD) is a rare, X linked disorder with skin and eye involvement (MIM 308800). We have studied a large British family with KFSD using polymorphic markers from Xp21-p23 and obtained a lod score of 2.056 at theta=0 with markers proximal and distal to the KFSD candidate region Xp22.13-p22.2 identified by Oosterwijk et al. Our data confirm the linkage to Xp22.13-p22.2 observed in the previously reported Dutch family, but fail to narrow the candidate interval for the KFSD locus.
The role of human papillomavirus (HPV) in the aetiology of in situ and invasive carcinoma of the genital tract is well established. In the rare disorder epidermodysplasia verruciformis (EV), in which patients develop extensive warts of unusual types and multiple cutaneous squamous cancers on light-exposed skin, current evidence suggests a probable role for a specific group of EV HPVs in the carcinogenic process. Determination of the possible role of HPV in the aetiology of non-melanoma skin cancers (NMSCs), which occur frequently in immunosuppressed organ allograft recipients, has been limited, until recently, by the lack of availability of a sensitive detection system for a wide range of cutaneous HPV types. We have used a combination of 2 sets of PCR primers to examine 68 benign and malignant tumours collected over a 12-year period from 25 renal allograft recipients. Cloning and sequencing of the PCR products were carried out to distinguish HPV DNA from cellular sequences. A combination of these techniques revealed HPV DNA in all viral warts, 65% of keratoses, 91% of intra-epidermal cancers and 91% of invasive squamous cancers. Both cutaneous and EV HPV types were detected, including 18 novel types. In 4 patients with multiple cancers, the most prevalent types were in the EV group: HPV 20, 23, 38 and 2 novel types, DL40 and DL267 (related to HPV 10 and 38, respectively). These 5 HPV types were present in a total of 73% of all malignant lesions tested. The technique described represents a reliable method of HPV DNA detection in NMSC. The EV group of HPVs predominate in the cancers, but the multiplicity of HPV types detected with double infection in some lesions suggests virus/virus in addition to virus/host interaction in the carcinogenic process.
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Renal allograft recipients (RARs) have a well-documented increased incidence of viral warts and cutaneous neoplasia, particularly those with long graft life and high sun exposure. A clinicopathological survey of 69 RARs in south-east Scotland, with follow-up periods of up to 28 years after transplantation, revealed marked variation in patient susceptibility to cutaneous malignancy with concomitant variation in HPV prevalence. Skin cancers were found in 34 patients. Eight patients showed high susceptibility [defined as more than four intraepidermal carcinomas (IECs) or invasive squamous cell carcinomas (SCCs)] 42 had intermediate susceptibility (1-3 IECs or SCCs, or >3 keratoses) and 18 had low susceptibility (< or = 3 keratoses and no cancers). SCCs, IECs and keratoses from the high-susceptibility group were found to have greater prevalences of human papillomavirus (HPV) DNA (56%, 45% and 50% respectively), than SCCs (0%) and IECs (33%) from intermediate-susceptibility RARs and keratoses (36%) from the combined intermediate- and low-susceptibility groups and compared with a group of immunocompetent controls (27%, 20% and 15% respectively). No differences in p53 protein accumulation, determined immunohistochemically, were observed in tumours from the three groups. Categorization of RARs by susceptibility to cutaneous malignancy provides clinically useful information, as significantly more high-susceptibility patients (38%) developed aggressive, potentially lethal anogenital or cutaneous squamous cell cancers than did patients in the intermediate group (5%, P=0.005) or the low-susceptibility group (0%).
The persistence of human papillomavirus at cutaneous sites may be due to impaired trafficking of immune effector cells to the epidermis. We investigated whether HPV infection modulates cytokine mRNA expression in skin, thereby influencing local immunity. The mRNA expression of tumour necrosis factor-alpha, interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-1 receptor antagonist (IL-1ra), IL-4, IL-8, IL-10, IL-12, granulocyte macrophage colony-stimulating factor, transforming growth factor-beta, interferon-gamma and amphiregulin were assayed in cutaneous warts and normal skin by semiquantitative reverse transcriptase-polymerase chain reaction. The expression of the cytokines was heterogeneous in the specimens but, of the 12 mRNA species investigated, only IL-10 mRNA was significantly downregulated in warts compared with normal skin (P = 0.002). IL-1 alpha mRNA expression was significantly upregulated in common warts (P = 0.019) and plantar warts (P = 0.003) compared with normal skin. The expression of IL-1 alpha and IL-1ra mRNAs were significantly correlated in plantar warts (P < 0.05). Warts expressing IL-1 alpha also expressed amphiregulin, and there was a significant correlation between the expression of these two genes (P < 0.05). It is possible that IL-1 alpha expression in cutaneous warts may modulate the growth of papillomavirus-infected keratinocytes, mediated by amphiregulin, thus ensuring viral persistence.
We report two cases of the trigeminal trophic syndrome, complicating peripheral and central interruption of the trigeminal sensory pathways. These cases illustrate the diagnostic and management problems that this syndrome presents.
Milia en plaque is an unusual eruption typically occurring in the retroauricular area. Two cases of this disorder occurring in a novel position and treated with oral minocycline are now reported.
Keratosis follicularis spinulosa decalvans is a rare, X-linked genodermatosis characterized by follicular hyperkeratosis, scarring alopecia of the scalp, eyebrows and eyelashes, corneal dystrophy and photophobia. We describe two cases from a large family, the first with keratosis follicularis spinulosa decalvans to be reported in the U.K.
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Renal allograft recipients suffer from a markedly increased susceptibility to premalignant and malignant cutaneous lesions. Although various aetiological factors have been implicated, little is known of the associated genetic events. In this study we initially employed immunocytochemical techniques to investigate the prevalence and localisation of accumulated p53 in over 200 cutaneous biopsies (including 56 squamous cell carcinomas) from renal allograft recipients and immunocompetent controls. In renal allograft recipients accumulated p53 was present in 24% of uninvolved skin samples, 14% of viral warts, 41% of premalignant keratoses, 65% of intraepidermal carcinomas and 56% of squamous cell carcinomas [squamous cell carcinoma and intraepidermal carcinoma differed significantly from uninvolved skin (P < 0.005) and viral warts (P < 0.01)]. A similar trend was revealed in immunocompetent patients (an older, chronically sun-exposed population) but with lower prevalence of p53 immunoreactivity: 25% of uninvolved skin samples, 0% of viral warts, 25% of keratoses, 53% of intraepidermal carcinomas and 53% of squamous cell carcinomas. These differences were not statistically significant. Morphologically, p53 immunoreactivity strongly associated with areas of epidermal dysplasia and the abundance of staining correlated positively with the severity of dysplasia. These data suggest that p53 plays a role in skin carcinogenesis and is associated with progression towards the invasive state. No correlation was observed between accumulated p53 and the presence of human papillomavirus (HPV) DNA in any of the lesions. Single-strand conformational polymorphism analysis (exons 5-8) was used to determine the frequency of mutated p53 in 28 malignancies with varying degrees of immunopositivity. p53 mutations were found in 5/9 (56%) malignancies with p53 staining in > 50% of cells, reducing to 1/6 (17%) where 10-50% of cells were positively stained and none where < 10% of cells were stained. These data imply that factors other than p53 gene mutation play a part in accumulation of p53 in skin cancers.
It is well established that renal allograft recipients (RARs) have an increased incidence of viral warts and premalignant and malignant cutaneous lesions, and the risk of their development increases in proportion to duration of graft survival. It has been postulated that, in addition to the effects of prolonged immunosuppression and previous sun exposure, human papillomaviruses (HPV) may also contribute to the carcinogenic process. In this study, the prevalence of HPV DNA was examined in a range of premalignant and malignant cutaneous tumours from 50 immunosuppressed patients (47 renal allograft recipients plus three cardiac allograft recipients) and 56 immunocompetent patients using Southern hybridisation as a low-stringency screening method and type-specific polymerase chain reaction (PCR) assays for eight HPV types. The combined results for renal allograft recipients show that HPV DNA was detectable in 79% of viral warts, 42% of premalignant keratoses, 33% of intraepidermal carcinomas, 43% of invasive squamous cell carcinomas and 16% of uninvolved skin specimens (squamous cell carcinomas/renal allograft recipients significantly different at P < 0.05 from uninvolved skin specimens/renal allograft recipients). In immunocompetent patients the pattern of HPV DNA prevalence was 100% for viral warts; 25% for keratoses, 23% for intraepidermal carcinomas, 22% for squamous cell carcinomas and 8% for uninvolved skin. No single HPV type predominated in tumour specimens from either group. More tumours were found to contain HPV DNA by Southern hybridisation analysis than PCR, indicating the presence of HPV types other than HPV 1, 2, 5, 6, 8, 11, 16 and 18 in some tumours. However, 'low cancer risk' HPV types 1, 2 and 6 as well as 'high cancer risk' HPV types 5 and 16 were specifically detected by PCR in a small number of neoplasms. These data suggest that multiple HPV types may contribute to cutaneous neoplasia in RARs and that they appear to act early in the process of carcinogenesis, perhaps by functioning as tumour promoters via stimulation of cell proliferation.
In vitro lymphoproliferative responses of peripheral blood mononuclear cells (PBMC) from patients with cutaneous warts, caused by infection with human papillomavirus type 1 (HPV-1) or type 2 (HPV-2), were assayed during the course of treatment. Purified HPV-1 and HPV-2 were used as antigens, as well as herpes simplex virus (HSV) and concanavalin A (Con A). All patients had normal percentages of subsets within the PBMC population and normal lymphoproliferative responses to Con A, and those with a clinical history of HSV infections had positive lymphoproliferative responses to HSV. Responses to both HPV antigens were poor. Only 10 of 100 assays of PBMC from 26 patients showed a stimulation index greater than 2. Addition of interleukin 2 made little difference in most cases. No correlation of clinical status of warts, i.e. improving, unchanged or resolved, with lymphoproliferation was found. When the PBMC were depleted of plastic-adherent cells and enriched for T cells, some samples which had not shown a lymphoproliferative response to HPV-1 or HPV-2 became positive; this response was abolished when the adherent cells were re-added. Thus it is possible that the adherent cell population from a proportion of patients contains cells which suppress lymphoproliferation, or that an immunoregulatory network is present so that lymphoproliferation does not take place in vitro without prior activation and cloning of T cells.