16 research outputs found
Expression of the apoptotic markers in normal breast epithelium, benign mammary dysplasia and in breast cancer
Apoptosis and proliferation are processes associated with the development and
progression of breast cancer. The sensitivity of tumour cells to the induction of
apoptosis depends on the balance between pro- and anti-apoptotic proteins.
The expression of Bak and Bcl-2 was examined using an immunohistochemical
method in 71 primary breast cancers. Furthermore, Bcl-2 and Bak were assessed
in the normal mammary gland as well as in benign mammary dysplasia adjacent
to breast cancer. Positive immunostaining for Bcl-2 was observed in 77.8% of
cases of normal breast epithelium (NBE), 93% of benign dysplasia without intraductal
proliferation (BBD) as well as in 94% of intraductal proliferative lesions of
the breast (BIPL). Expression of Bak was detected in 39% of cases of NBE, 45%
of BBD and in 67% of BIPL. In breast cancer Bcl-2 and Bak expression was found
in 83% and 70% of the cases studied, respectively. Increased Bcl-2 expression in
primary tumours significantly correlated with favourable prognostic factors, namely
pT1, G2 and lack of metastases to the regional lymph nodes (p < 0.01,
p < 0.03, p < 0.02, respectively). There were no relationships between Bak and
the clinicopathological features studied, but our results indicate changes in the
expression of Bak during breast cancer development and progression. It would
appear to be important to assess and compare pro- and anti-apoptotic proteins
between normal mammary gland, benign mammary dysplasia and the primary
tumours of breast cancer. This knowledge should be helpful in understanding
breast cancer development and progression
N-cadherin, beta-catenin and connexin 43 expression in astrocytic tumours of various grades
Introduction: Astrocytic tumors are the most
common primary brain tumors, but little is known about
their etiology and prognostic factors. N-cadherin and
beta-catenin are adhesive proteins, and are often
overexpressed in many types of cancers, including breast
or colorectal cancer, resulting in better prognosis.
Connexin 43 is a gap junction protein involved in cellcell signaling pathway taking part in the process of
carcinogenesis. The aim of the study was to evaluate Ncadherin, beta-catenin and connexin 43 expression in
astrocytic tumors of various grades.
Materials and methods: We examined 131 cases of
astrocytic tumors, including 26 cases of diffuse
astrocytoma (group I), 44 anaplasic astrocytomas (group
II) and 61 glioblastoma cases (group III) - primary and
secondary. To evaluate N-cadherin, beta-catenin and
connexin 43 expression, we used immunohistochemical
reaction with specific antibodies (Santa Cruz
Biotechnology). The obtained results were correlated
with clinical and morphological features.
Results: Beta-catenin expression was observed in
69.3% of diffuse astrocytomas, 75% of anaplastic
astrocytomas, and 82% of glioblastoma cases. Ncadherin expression was observed in 92.3% of diffuse
astrocytomas, 90.1% of anaplastic astrocytomas, and in
all glioblastoma cases. Connexin 43 was observed in
76.9% of diffuse astrocytomas, and in all cases of
anaplastic astrocytomas and glioblastomas. Beta-catenin
expression was significant within the nucleus of
neoplastic cells in groups I and II. In group III, staining
was observed only in the cellular membranes. Ncadherin and connexin 43 expression was observed only
in the cells’ membranes. In glioblastomas, both primary
and secondary, all protein expression was significant
within the cells surrounding the necroses and blood
vessels and weak or absent in the tumor’s margins.
Conclusion: Our study shows that beta-catenin
nuclear expression in group of diffuse astrocytomas and
anaplastic astrocytomas is evidence for transcriptional
function of beta-catenin in those groups. Strong Ncadherin and connexin 43 expression in those groups
may be evidence for their role in tumor formation and
progression. However, in glioblastomas a very important
role of all examined proteins is generating intracellular
connections to facilitate the escape of tumor cells from
the effects of hypoxia or their accumulation around the
blood vessels rather than tumor invasion into the brain
parenchyma
Frequent expression of somatostatin receptor 2a in olfactory neuroblastomas: a new and distinctive feature.
Olfactory neuroblastoma (ONB) is a malignant neuroendocrine neoplasm with a usually slow course, but with considerable recurrence rate. Many neuroendocrine tumors have shown good response to the treatment with somatostatin analogs and somatostatin radioreceptor therapy. In ONBs, there are scarce data on somatostatin-based treatment and the cellular expression of somatostatin receptors (SSTR), the prerequisite for binding and effect of somatostatin on normal and tumor cells. The aim of our study was to investigate the immunohistochemical expression of SSTR2A and SSTR5 in a cohort of 40 ONBs. In addition, tissue microarrays containing 40 high-grade sinonasal carcinomas as well as 6 sinonasal lymphomas, 3 rhabdomyosarcomas, and 3 Ewing sarcomas were evaluated. Volante system was applied for staining evaluation. Thirty cases (75%) were immunopositive for SSTR2A and 3 (7.5%) for SSTR5. Among the 30 SSTR2A-positive ONBs, 19 tumors (63.3%) scored 2+ and 11 (36.7%) scored 3+. All SSTR5-positive ONBs scored 2+. Neither sinonasal carcinomas nor sinonasal small round blue cell neoplasms expressed SSTR2A or SSTR5. The frequent expression of SSTR2A provides a rationale for radioreceptor diagnosis and therapy with SST analogs in ONBs. SSTR2A expression in ONBs is a helpful adjunct in the differential diagnosis of ONBs
Epidemiology of ocular surface squamous neoplasia in Africa.
OBJECTIVES: To describe the epidemiology and an aetiological model of ocular surface squamous neoplasia (OSSN) in Africa. METHODS: Systematic and non-systematic review methods were used. Incidence was obtained from the International Agency for Research on Cancer. We searched PubMed, EMBASE, Web of Science and the reference lists of articles retrieved. Meta-analyses were conducted using a fixed-effects model for HIV and cigarette smoking and random effects for human papilloma virus (HPV). RESULTS: The incidence of OSSN is highest in the Southern Hemisphere (16° South), with the highest age-standardised rate (ASR) reported from Zimbabwe (3.4 and 3.0 cases/year/100 000 population for males and females, respectively). The mean ASR worldwide is 0.18 and 0.08 cases/year/100 000 among males and females, respectively. The risk increases with exposure to direct daylight (2-4 h, OR = 1.7, 95% CI: 1.2-2.4 and ≥5 h OR = 1.8, 95% CI: 1.1-3.1) and outdoor occupations (OR = 1.7, 95% CI: 1.1-2.6). Meta-analysis also shows a strong association with HIV (6 studies: OR = 6.17, 95% CI: 4.83-7.89) and HPV (7 studies: OR = 2.64, 95% CI: 1.27-5.49) but not cigarette smoking (2 studies: OR = 1.40, 95% CI: 0.94-2.09). The effect of atopy, xeroderma pigmentosa and vitamin A deficiency is unclear. CONCLUSIONS: Africa has the highest incidence of OSSN in the world, where males and females are equally affected, unlike other continents where male disease predominates. African women probably have increased risk due to their higher prevalence of HIV and HPV infections. As the survival of HIV-infected people increases, and given no evidence that anti-retroviral therapy (ART) reduces the risk of OSSN, the incidence of OSSN may increase in coming years