Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0349506 (photosensitivity)
 4,145 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ultraviolet (UV) light generates two major DNA lesions: cyclobutane pyrimidine dimers (CPDs) and pyrimidine-(6-4)-pyrimidone photoproducts (6-4PPs), but the specific participation of these two lesions in the deleterious effects of UV is a longstanding question. In order to discriminate the precise role of unrepaired CPDs and 6-4PPs in UV-induced responses triggering cell death, human fibroblasts were transduced by recombinant adenoviruses carrying the CPD-photolyase or 6-4PP-photolyase cDNAs. Both photolyases were able to prevent UV-induced apoptosis in cells deficient for nucleotide excision repair (NER) to a similar extent, while in NER-proficient cells UV-induced apoptosis was prevented only by CPD-photolyase, with no effects observed when 6-4PPs were removed by the specific photolyase. These results strongly suggest that both CPDs and 6-4PPs contribute to UV-induced apoptosis in NER-deficient cells, while in NER-proficient cells, CPDs are the only lesions responsible for UV-killing, probably due to the rapid repair of 6-4PPs by NER. As a consequence, the difference in skin photosensitivity, including carcinogenesis, of most of the xeroderma pigmentosum patients and of normal people is probably not only a quantitative aspect, but depends on the type of DNA damage induced by sunlight and its rate of repair.
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PMID:CPDs and 6-4PPs play different roles in UV-induced cell death in normal and NER-deficient human cells. 1809 46

Xeroderma pigmentosum (XP) is an autosomal recessive (AR) condition characterized by photosensitivity and inability to repair ultra-violet (UV) induced DNA damage. Patients diagnosed with XP, presenting to the Paediatric ophthalmology department of Al-Shifa Trust Eye Hospital, Rawalpindi, were evaluated and followed-up over a period of one year, for the effects of the disease process on vision and for the development of ocular tumours. Excision of the tumours, if present, was performed under general anaesthesia. Counselling of the patients was done. Referral to oncologist and dermatologist was made, if so warranted, after histopathology of excision biopsy.
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PMID:Ocular manifestations of xeroderma pigmentosum. 1818 42

Xeroderma pigmentosum type C (XPC) is a rare autosomal recessive disorder that occurs due to inactivation of the XPC protein, an important DNA damage recognition protein involved in DNA nucleotide excision repair (NER). This defect, which prevents removal of a wide array of direct and indirect DNA lesions, is associated with a decrease in catalase activity. To test the hypothesis of a novel photoprotective approach, we irradiated epidermis reconstructed with XPC human keratinocytes sustainably overexpressing lentivirus-mediated catalase enzyme. Following UVB irradiation, there was a marked decrease in sunburn cell formation, caspase-3 activation and p53 accumulation in human XPC-reconstructed epidermis overexpressing catalase. Moreover, XPC-reconstructed epidermis was more resistant to UVB-induced apoptosis than normal reconstructed epidermis. While not correcting the gene defect, indirect gene therapy using antioxidant enzymes may be of help in limiting photosensitivity in XPC and probably in other monogenic/polygenic photosensitive disorders characterized by ROS accumulation.
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PMID:Catalase overexpression reduces UVB-induced apoptosis in a human xeroderma pigmentosum reconstructed epidermis. 1820 16

The clinical presentation of trichothiodystrophy type F includes photosensitivity, ichthyosis, brittle hair, intellectual impairment, decreased fertility, and short stature, often referred to as the PIBIDS syndrome. While many of these patients demonstrate features also found in xeroderma pigmentosum patients, including similar nucleotide excision repair gene defects and photosensitivity, PIBIDS patients rarely demonstrate cutaneous malignancies. This case report demonstrates the rare presentation of squamous cell carcinoma developing in a PIBIDS patient.
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PMID:A rare presentation of squamous cell carcinoma in a patient with PIBIDS-type trichothiodystrophy. 1842 98

Xeroderma pigmentosum (XP) is a rare, autosomal recessive disorder characterized by photosensitivity, cutaneous pigmentary changes, premature skin ageing and development of various cutaneous and internal malignancies at an early age as a result of a defect in nucleotide excision repair following ultraviolet light exposure. Cutaneous angiosarcomas are aggressive neoplasms that are rarely associated with XP. In this communication, we report the case of a 40-year-old male patient with XP who developed an angiosarcoma of the face and discuss the implications of this association in view of recent developments in this field.
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PMID:Cutaneous angiosarcoma in a patient with xeroderma pigmentosum. 1900 76

Xeroderma pigmentosum (XP) was first described in 1874 by Hebra and Kaposi. [1] It is a rare autosomal recessive disorder characterized by photosensitivity, pigmentary changes, premature skin aging, and malignant tumor development due to cellular hypersensitivity to ultraviolet radiation resulting from a defect in DNA repair. The basic defect in XP is in nucleotide excision repair (NER), leading to deficient repair of damaged DNA. A 12-year-old boy presented with a large growth over the right side of the forehead. The lesion was first noticed before two years as a 2 x 2 cm 2 mass. It was slowly growing and attained the present size of 10 x 8 x 7 cm 3 . The surface showed ulceration with areas of hemorrhage and blackish pigmentation. Also, the patient had hyperpigmented macules over the skin since early childhood. The macules appeared initially over the face and later developed over the other areas of the body. The macules were more over the sun exposed areas. He also had photophobia and both eyes showed corneal opacities. Histopathological examination of the excised growth showed features consistent with melanoma. This case is being presented because of its rare association with xeroderma pigmentosum patients in India.
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PMID:A case of melanoma in xeroderma pigmentosum. 1980 62

Cerebro-oculo-facio-skeletal (COFS) syndrome is an autosomal recessive inherited disorder characterized by congenital microcephaly, congenital cataracts and/or microphthalmia, arthrogryposis, severe developmental delay, severe postnatal growth failure and facial dysmorphism with prominent nasal root and/or overhanging upper lip. This syndrome is now recognized as a disorder belonging to the spectrum of inherited defects in Nucleotide Excision Repair (NER) resulting in profound photosensitivity. In COFS syndrome, as in Cockayne syndrome, DNA repair is impaired in the transcription-coupled NER pathway, but not in the global genome NER pathway. Fourteen cases so far described as COFS syndrome have been studied at the molecular levels. All mutations have been found in Cockayne syndrome gene, CSB, xeroderma pigmentosum genes, XPD and XPG and ERCC1 gene involved in the transcription-coupled NER pathway.
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PMID:Cerebro-oculo-facio-skeletal syndrome. 2068 8

Photosensitivity in childhood is caused by a diverse group of diseases. A specific sensitivity of a child's skin to ultraviolet light is often the first manifestation or a clinical symptom of photodermatosis. It might indicate a serious underlying systemic disease such as lupus erythematosus or dermatomyositis, or a rare group of genetic skin disorders like Xeroderma pigmentosum, Cockayne syndrome, Trichothyodystrophy, Bloom syndrome, Rothmund-Thomson and Kindler syndrome as well as metabolic disorders and cutaneous porphyria. Photosensitivity secondary to topical or systemic agents may also cause photosensitivity in children. Early recognition and prompt diagnosis may prevent complications associated with unprotected exposure to sunlight and avoid actinic injuries that can lead to malignant skin changes.
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PMID:Photosensitivity skin disorders in childhood. 2130 30

Xeroderma pigmentosum (XP) is an uncommon inherited dermatological disorder characterized by a high degree of skin photosensitivity with development of carcinomas at an early age. Neurological manifestations may be encountered in XP but few detailed descriptions have been provided. Here we describe a sister and a brother presenting chorea, dystonia, myoclonus, ataxia and polyneuropathy related to XP.
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PMID:Xeroderma pigmentosum: a rare cause of chorea. 2151 43

Xeroderma pigmentosum is a genodermatosis characterized by photosensitivity and the development of cutaneous and internal malignancies at an early age. The basic defect underlying the clinical manifestations is a nucleotide excision repair defect, leading to defective repair of DNA damaged by ultraviolet radiation. These patients exhibit enhanced sensitivity to ionizing radiation. Patients with xeroderma pigmentosum who are younger than 20 years of age have a greater than 1000-fold increased risk of developing skin cancer. Early detection of these malignancies is necessary because they are fast growing, metastasize early and lead to death. Although, early detection and treatment of cutaneous malignancies will reduce the morbidity and mortality, genetic counseling remains the most important measure for preventing xeroderma pigmentosum. We report a case of xeroderma pigmentosum in an 18-year-old male presenting with multiple cutaneous malignancies: squamous cell carcinoma, malignant melanoma and pigmented basal cell carcinoma.
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PMID:Multiple cutaneous malignancies in a patient of xeroderma pigmentosum. 2176 16


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