EGFR (epidermal growth factor receptor), p53, and proliferative markers provide some clues as to the formation of several tumours. In this study the mechanism of the genesis of parathyroid adenomas was investigated using immunohistochemistry. Sections of parathyroid adenomas from 12 cases were stained using PCNA (proliferating cell nuclear antigen), EGFR, and p53 immunohistochemistry. Correlations between PCNA LI (labelling index), EGFR expression, p53 expression, age, serum parathormone, Ca and P levels, and tumour diameter were investigated. PCNA LI was 45.8+/-33.1 (mean+/-standard deviation) and all the cases were somewhat positive. Five cases (41.67 %) were EGFR positive. Maximum 10 % of the cells were positive in these cases. All the cases were p53 negative. There was a correlation between PCNA LI and serum parathormone level (r=0.607, p=0.036). According to these results, parathormone synthesis is high when the proliferative activity of parathyroid adenoma is high. Four of the five EGFR-positive patients were below 35 years of age. These data may indicate that formation of parathyroid adenoma in young patients is related to a mechanism involving EGFR. Absence of p53 expression suggests that p53 mutation is not a common component of parathyroid adenomas.

Cellular proliferation programmed cell death (apoptosis) are associated with tumor growth in general, and prostate cancer growth in particular. The aim of this study was to examine the expression of the apoptosis regulating genes bcl-2 and p53 and Gleason score in core needle biopsy specimens of prostate cancer using immunohistochemistry. We studied bcl-2 and p53 expression in 12 cases of low grade (Gleason score 2-5), 12 cases of intermediate grade (Gleason score 6-7) and 8 cases of high grade (Gleason score 8-10) prostate cancer. Overexpression of bcl-2 was noted in 3 of 32 patients (9.32%). One of them was high grade; others were intermediate grades. Expression of p53 was observed in 3 of low grades; others were high grade. The statistical analysis of present data suggest that there is no significant relation between p53 and bcl-2 expression and Gleason score in prostate cancer.

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Placental biopsy by frozen sectioning might be a useful and quick method of evaluation for placental pathology. Theoretically, fetal status could be more precisely evaluated by combining prenatal placental biopsy by permanent section with conservative ante-partum well-being tests.

The p53 gene is a tumor suppressor gene which is located on band 13p of chromosome 17. It encodes a 53-kd nuclear phosphoprotein, and has been found in all mammalian cells. It is thought to play a role in the control of the cell cycle. The wild type p53 protein inhibits cell proliferation by arresting cells in the G1 phase of the cell cycle, and loss of this activity can lead to neoplastic transformation.1-3 Mutations in p53 gene are the most common genetic alterations in several human malignancies, including lung, breast, colorectal, ovarian and cutaneous neoplasms, although the prognostic value of altered p53 expression is still debated. [4][5][6] Under physiological conditions, the wild type protein has a short half-life to allow immunohistochemical detection.7 However, the mutant type is more stable than the wild type, and is detectable in cell nuclei by standard immunohistochemical staining procedures. 1,7 To investigate the role of p53 in cell proliferation, we focused on markers of the cell cycle whose expression could be correlated with p53 immunohistochemical detection. One such marker is the proliferating cell nuclear antigen (PCNA). PCNA is a 36-kd nuclear polypeptide that is related to cell proliferation. PCNA, an auxilliary protein for DNA polymerase, is identical to cyclin, synthesized during the late G1 to S phase. The synthesis of PCNA is reported to be directly correlated with DNA replication and cell proliferation. 8,9 Our hypothesis was that p53 overexpression may be associated with increased cell proliferation, which might affect the clinical outcome of non-small cell lung carcinomas (NSCLC) and small cell lung carcinomas (SCLC). We examined the expression of p53 and PCNA immunohistochemically. The aim of this study was to evaluate the relationship of p53 and age, sex, nodal involvement, tumor stage, tumor size and proliferative activity in NSCLC and SCLC. Materials and MethodsThis study was based on 60 cases of primary lung carcinoma taken from the files of the Pathology Department, School of Medicine, Akdeniz University. Tumor tissue was obtained by biopsy (n=22, SCLC) or surgical resection (n=30, NSCLC and n=8, SCLC). The pathologic features of the surgical specimens were classified and staged according to the World Health Organization criteria and TNM staging system. Cases of NSCLS consisting of 24 squamous, 1 adenosquamous and 5 adenocarcinomas were examined. In the resection specimens, the size of the tumor and the tumor stage, vessel and nerve invasion, lymph node and pleura involvement were evaluated.All specimens were fixed in 10% formalin and routinely processed for paraffin wax embedding. Sections were cut into 5 μ pieces, mounted on glass and dried overnight at 37°C. All sections were then deparaffinized in xylene, rehydrated through alcohol and washed in phosphate-buffered saline. This buffer was used for all subsequent washes and for dilution of the antibodies. Sections for p53 detection were heated in a microwave oven twice for 5 minutes at 700 W in citrate buffer (pH: 6). Mono...