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Tanja Batinac

Publications and source records attributed to Tanja Batinac.

15 recordsLinked to original sources
PubMed2007

Lyme borreliosis and multiple sclerosis are associated with primary effusion lymphoma.

Multiple sclerosis (MS) is a chronic disease of the central nervous system characterized by chronic inflammation and demyelination. Studies suggested that the viral, especially Epstein-Barr virus infection, and bacterial infections, especially Borrelia burgdorferi infection, play a role in etiology of MS. MS prevalence parallels the distribution of the Lyme disease pathogen B. burgdorferi. Criteria used for diagnosis of MS can also be fulfilled in other conditions such as Lyme disease, a multisystem disorder resulting from infection by the tick-borne spirochete, B. burgdorferi. In the late period of Lyme disease demyelinating involvement of central nervous system can develop and MS can be erroneously diagnosed. A Lyme borreliosis can mimick central nervous system lymphoma. Also, B. burgdorferi has been implicated not only in etiology of MS, but also in etiology of lymphoma. Studies suggested that there is an increased risk of non-Hodgkin lymphoma in patients, who had a history of autoimmune diseases such as MS and that both non-Hodgkin's lymphomas and Hodgkin's disease were associated with Epstein-Barr virus infection. A small group of lymphomas called primary effusion lymphomas (PEL) is a recently individualized form of non-Hodgkin's lymphoma (WHO classification) that exhibit exclusive or dominant involvement of serous cavities, without a detectable solid tumor mass. These lymphomas have also been linked to Epstein-Barr virus and human herpes virus type 8 infections but virus negative cases have been described. Therefore, we propose that MS and neuroborreliosis are linked to central nervous system primary effusion lymphomas. As a first step in confirming or refuting our hypotheses, we suggest a thorough study of CSF in the patients suspected for the diagnosis of MS and Lyme borreliosis.

Humans↗
PubMed2006

Apoptosis and immune response are responsible for the site-specific incidence of non-melanoma skin cancer.

UNLABELLED: Generally, the cumulative UV exposure correlates with the site-specific incidence of skin cancer but more detailed analysis showed that the frequency of BCC of some facial regions cannot be explained with site-specific UV exposure. Apoptosis plays a central role in cancer development due to suppressed process of programmed cell death. Anatomic localization, UV and senescence can influence expression of apoptosis related molecules resulting in advantage of cancer cells development and tumor progression. Anti-tumor immune response, as an important factor in elimination of cancer cells, is also modified by UV radiation and aging, further contributing to cancer progression and its development. HYPOTHESIS: UV radiation, senescence and proliferation intensity influence the expression of apoptosis related molecules in normal keratinocytes. Mutated cells express altered molecules with different degree of antigenicity. We propose that small differences in the expression of pro- and anti-apoptotic molecules in the keratinocytes in association with the local immune reaction (modulated also by UV radiation) determine the type of the non-melanoma skin cancer as well as their frequency (site-specific incidence). In vitro and in vivo models could explain how the modulation of UV can influence the apoptotic system and local immune reaction, while animal experiments could explain different site-specific incidence (frequency) of the same tumor. Better understanding of these mechanisms could lead to development of different therapeutic approaches for early elimination of cancer prone cells or cells in early stages of cancer development. The same model could be used to explain the site-specific localization of other types of cancer (i.e. melanoma) or benign tumors.

Aging↗
PubMed2006

Telomerase in anti-tumor response.

Telomerase is responsible for maintaining the length of telomeres at the end of chromosomes. It protects chromosomes from degradation and aberrant recombination during replication prolonging the life span of the cell. Human telomerase reverse transcriptase (hTERT) is highly expressed in >85% of cancer cells but its expression is repressed in most human somatic cells. It has been shown that expression of human telomerase reverse transcriptase greatly extends the life span of both human CD8+ and CD4+ T cells during activation and proliferation. hTERT-positive tumor cells can induce cytotoxic T lymphocyte response as well as T helper response. On the other hand, it is possible that cytotoxic immune response to hTERT-positive tumor cells can cause autoimmune reaction directed against T cells in a tumor bearing host. This could lead to apoptosis and decreased number of activated T cells and insufficient anti-tumor immunity resulting in tumor progression.

Apoptosis↗
PubMed2006

The relationship between telomerase activity and proliferation in cutaneous melanoma.

Telomerase is a ribonucleoprotein reverse transcriptase which RNA component (TERC) and reverse transcriptase (TERT) function together to elongate telomeres. If cells are to survive and proliferate indefinitely, telomere preservation is essential for the immortalization process. Somatic cells rarely possess TA, but over 90% of tumor cells express active telomerase. Increased cell proliferation and deregulation of cell cycle occur in human cancers, including cutaneous melanoma. The exact nature of links between TA, cell proliferation and apoptosis has not been extensively elucidated in cutaneous melanoma. We hypothesize a relationship between TA and cutaneous melanoma cell proliferation in a way that TA in telomere elongation is only an early event in cell immortalization. The telomere elongation makes their proliferation possible and being, at the same time, one of its limiting factors. But the TA other than telomere elongation (TERC independent) is crucial to initiate or restore melanoma cell proliferation. On the other hand, TA in telomere elongation, together with other factors (for example TNF), has an active anti-apoptotic role. This way melanoma cells overwhelm the apoptotic defense mechanisms, finally resulting in their indefinite proliferation. In evaluation of our hypothesis, we suggest thorough studies of both telomerase activity and proliferation in cutaneous melanoma on multiple checkpoints and targets. We also suggest combined analyses of TA and telomere length. This approach seems inevitable since it is obvious that telomerase is no longer just for the elongation of telomeres and, to our knowledge, most of the studies conducted so far evaluated TA as an expression of a single subunit or associated molecule.

Animals↗
PubMed2006

Expression of cell cycle and apoptosis regulatory proteins in keratoacanthoma and squamous cell carcinoma.

Some authors view keratoacanthoma (KA) as a variant of squamous cell carcinoma (SCC), while others consider it a separate entity that must be distinguished from SCC. Involution displayed by KA is an important difference between these two entities. It has been suggested that apoptosis plays a role in the involution process of KA, although the exact trigger for it remains unclear. A hundred and fifty specimens were included in this study, 30 cases for each of the following groups: normal skin (NS), proliferative keratoacanthoma (pKA), regressing keratoacanthoma (rKA), well-differentiated squamous cell carcinoma (wdSCC), and poorly differentiated squamous cell carcinoma (pdSCC). They were immunohistochemically examined for the expression of p53, Ki-67, bak, and bcl-2. Significantly higher p53 and Ki-67 expressions were observed in all tumor lesions examined as compared with NS. There was higher bak expression in KAs compared to NS and a significant reduction of bak expression in pdSCC together with a significant reduction of bak expression in SCCs compared to pKA. Bcl-2 expression was similar in NS and SCCs, but was lower in rKA. We found a significant positive correlation between p53 and Ki-67, p53 and Bak in NS and examined skin tumors. Lower bcl-2 expression in conjunction with higher bak expression in rKA suggests a possible role of these apoptosis-regulating proteins in tumor regression. In contrast to this finding, a steady level of bcl-2 expression in pdSCC combined with lower bak expression levels and a high proliferation rate could contribute to progression and aggressiveness in these tumors. Bak and p53 expression is a sun-related and age-dependent process in NS and skin tumors.

Adult↗
PubMed2006

Possible key role of granzyme B in keratoacanthoma regression.

It is still controversial whether keratoacanthoma is to be considered as a well differentiated variant of squamous cell-carcinoma or a separate entity. As opposed to malignant potential of squamous cell-carcinoma, keratoacanthoma is characterized by a spontaneous regression. However, in some cases, otherwise typical keratoacanthoma can behave aggressively showing the signs of perineural and perivascular invasion and metastases in regional lymph nodes. The most important feature that separates these two closely related entities is a tendency of keratoacanthoma to regress. Causes and detailed mechanism of this regression are still not completely elucidated. Within the past few years, it has become evident that the molecular events regulating cell survival and apoptosis are important contributors to the overall kinetics of benign and malignant cell growth. Immunological mechanisms have been implicated in a phenomenon of spontaneous tumor regression. Recent studies suggested that the tumor regression is dependent mainly on the immune response mediated by cytotoxic T lymphocytes (CD8+), together with helper T cells (CD4+). Cytotoxic T lymphocytes can kill tumor cells and mediate tumor regression in vivo through two distinct molecular mechanisms: Fas/Fas ligand and granzyme B/perforin mediated pathways. Tumor cells are capable of developing different escape mechanisms in order to overcome their sensitivity to apoptotic signals. However, granzyme B, contained in cytolytic granules released upon target cell recognition, can also cause tumor cell death and consequently tumor regression by direct damage to non-nuclear structures through a caspase-independent pathway. Therefore, we propose a key role of plasticity in the granzyme B mediated cell death pathway in the killing of changed tumor cells, resulting in keratoacanthoma regression through apoptosis or direct damage of tumor cells. On the other hand, insufficient activation of cytotoxic T lymphocytes and decreased release or activity of granzyme B could be responsible for squamous cell-carcinoma progression and occasional aggressive behavior in keratoacanthomas. As a first step in confirming or refuting our hypothesis, we suggest a thorough immunohistochemical study of the presence of granzyme B and its activity in keratoacanthoma and squamous cell-carcinoma samples. To our knowledge, no such study has been performed so far.

Animals↗
PubMed2005

Expression of p53 and apoptosis in discoid lupus erythematosus.

AIM: To investigate whether p53 expression and apoptosis play a role in the pathogenesis of discoid lupus erythematosus (DLE) and whether they are associated with a hyperproliferative state in the epidermis of DLE lesions and epidermal atrophy. METHODS: A total of 70 skin biopsy specimens, 35 DLE and 35 normal, were used. Expression of protein p53 and Ki-67 was examined immunohistochemically. Apoptotic cells were identified by terminal deoxynucleotidyl transferase (TdT)-mediated nick end labeling (TUNEL). Histopathological examination of hematoxylin-eosin-stained sections of DLE included analysis and scoring of epidermal atrophy and other histopathological parameters. RESULTS: p53 expression was greater in DLE than in normal skin (14.5 vs 0.6%, P<0.001). Ki-67 expression was also greater in DLE than in normal skin (8.0 vs 3.1%, P<0.001). A significant positive correlation between p53 and Ki-67 expression was found in both groups (normal skin, r=0.46, P<0.009; DLE, r=0.72, P<0.001). A significant negative correlation (r=-0.75, P<0.001) between Ki-67 expression and the intensity of epidermal atrophy was found. The degree of apoptosis in the epidermis of DLE lesions with higher Ki-67 and p-53 expression was higher than when the expression of these molecules was low (3.0+/-1.8 vs 1.6+/-1.5 on a scale from 0-5; P=0.048). CONCLUSION: Aberrant p53 expression occurs in the keratinocytes of DLE and is associated with keratinocyte hyperproliferation and epidermal atrophy. Accumulation of p53 protein, together with an extensive apoptosis, suggests that the activation of a p53-induced apoptotic pathway may play a role in the pathogenesis of skin lesions in DLE.

Adult↗
PubMed2005

Recurrent pleomorphic adenoma of epipharynx following irradiation therapy.

We present a case of a 67-year-old female patient having a pleomorphic adenoma of epipharynx with intact fibrous capsula, which despite its benignity recurred and, moreover, responded quite well to irradiation therapy. The patient, at first, refused any therapy. Three years later, when the CT showed tumor enlargement she accepted only irradiation therapy, resulting in significant reduction of tumor size. Five years later the tumor recurred but without malignant transformation. She still refused surgery, but accepted re-irradiation therapy. After a three-year follow-up the patient has no symptoms of the tumor enlargement. This case shows that the irradiation therapy might be quite effective in the treatment of pleomorphic adenoma of epipharynx, but it is clear that much better results could be accomplished in combination with the surgery. In cases when the surgery is rejected or not possible because of the vicinity of the vital structures, we recommend the irradiation therapy as a therapy of the choice.

Adenoma, Pleomorphic↗
PubMed2004

Heliomarinotherapy in psoriasis.

Heliomarinotherapy is an important therapeutic option in the treatment of psoriasis. Investigations on heliomarinotherapy carried out in Veli Losinj, Croatia showed that the remissions of psoriasis after such treatment were long lasting, side effects slight, and use of corticosteroids not necessary.

Climatotherapy↗
PubMed2003

Protein p53--structure, function, and possible therapeutic implications.

Cell cycle is driven by a number of positive and negative regulatory phosphorylation and dephosphorylation events that ultimately influence the activity of transcription factors. Normal skin architecture depends on the regulation mechanisms of cell proliferation and differentiation and on apoptosis. Complex interaction of different factors in the regulation of these mechanisms, aimed at maintaining constant desquamation, is often changed in skin diseases. The main difference between normal cells and tumor cells results from discrete changes in specific genes important for cell proliferation control mechanisms and tissue homeostasis. These genes are mainly proto-oncogenes or tumor-suppressor genes, and their mutation could play a role in cell hyperproliferation and carcinogenesis. Tumor-suppressor genes normally function as a physiological barrier against clonal expansion or mutation accumulation in the genome. They also control and arrest growth of the cells that hyperproliferate due to oncogene activity. Alteration or DNA damage in tumor-suppressor genes and oncogenes are considered key events in human carcinogenesis. Tumor-suppressor protein p53 is an important transcription factor, which plays a central role in the cell cycle regulation mechanisms and cell proliferation control, and its inactivation is considered a key event in human carcinogenesis. The role of p53 protein in the cell cycle, high proportion of tumors with mutated p53 gene, and accumulation of significant amount of knowledge on molecular biology of this protein make this molecule especially attractive for development of new therapeutic approaches. Main strategies for development of new antineoplastic therapies are based on "wild-type" p53 protein acting as a tumor suppressor, selective apoptosis inductor, and a protein able to arrest cell cycle.

Genes, p53↗
PubMedDate not supplied

Angioimmunoblastic lymphadenopathy with dysproteinemia following doxycycline administration.

Angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is a primary lymphoproliferative T-cell disorder, currently classified as a peripheral T-cell non-Hodgkin's lymphoma. AILD is characterized by generalized lymphadenopathy, hepatosplenomegaly, immunological abnormalities, polyclonal hypergammaglobulinemia and anemia. We report a case of AILD in an 80-year-old male who presented with a generalized pruritic maculopapular eruption and fever following doxycycline administration. The maculopapular rash progressed to formation of confluent nodules, plaques and finally erythroderma with lymphadenopathy and hepatosplenomegaly. Blood analysis revealed an elevated erythrocyte sedimentation rate and polyclonal hypergammaglobulinemia. Lymph node biopsy showed almost complete effacement of the nodal architecture with diffuse proliferation of small vessels forming an arborizing network, surrounded by atypical lymphocytes, usually CD3+ CD4+ and occasionally CD3+ CD8+. There were also larger cells (immunoblastic shape) that displayed CD20 positively, some scattered plasma cells, and eosinophils. Histology of a cutaneous lesion showed spongiosis and infiltration of the epidermis by atypical lymphocytes with large hyperchromatic nuclei, perivascular dermal lymphocytic infiltrate (CD3+) mixed with plasma cells and occasional large immunoblasts (CD20+). During hospitalization the patient developed hemolytic anemia (Coombs positive) and lung metastases. The prognosis of AILD is generally poor, with a median survival of less than 20 months. Our patient died two and a half months after the diagnosis was made due to sepsis caused by Staphylococcus aureus isolated in hemoculture.

Aged↗
PubMedDate not supplied

p53 protein expression and cell proliferation in non-neoplastic and neoplastic proliferative skin diseases.

AIMS AND BACKGROUND: The p53 protein is essential for the regulation of cell proliferation and its aberrant accumulation is usually seen in malignant tumors but also occurs in squamous epithelium of inflammatory skin diseases characterized by hyperproliferation. The aim of this study is to elucidate the role of the p53 tumor suppressor protein in the pathogenesis of different hyperproliferative, non-malignant and malignant skin diseases, and to determine the association between p53 overexpression and cell proliferation. We also investigated the influence of aging on p53 and Ki-67 protein expression. METHODS: One hundred and fifty skin specimens divided into 30 samples each of normal skin (NS), psoriatic skin (PS), keratoacanthomas (KA), basal cell carcinomas (BCC), and squamous cell carcinomas (SCC) were examined immunohistochemically to assess p53 and Ki-67 protein expression. RESULTS: p53 immunostaining of NS, PS, KA, BCC and SCC was detected in 39.0%, 46.7%, 66.7%, 80% and 86.7% of cases, respectively. Median values and ranges of p53 protein expression were as follows: 0.0% (range, 0.0-1.8%) in NS, 0.0% (range, 0.0-6.5%) in PS, 9.2% (range, 0.0-24.0%) in KA, 19.3% (range, 0.0-48.1%) in BCC and 30.1% (range, 0.0-68.1%) in SCC. p53- and Ki-67-positive cells were present in basal (NS) and suprabasal layers (PS), and not only in cancer nests of KA, BCC and SCC but also in dysplastic and even morphologically normal epidermis adjoining cancers. The positivity of p53 and Ki-67 proteins differed significantly among the groups, with no differences in p53 expression between NS and PS and in Ki-67 expression between PS and KA. Within all groups there was a significant correlation between p53 and Ki-67 expression. Lesion location and patient age, with the exception of location in PS and age in BCC, were significantly related to p53 and Ki-67 expression in all groups. CONCLUSIONS: Our findings suggest that p53 overexpression occurs mainly in neoplastic skin lesions, although it may also occur in squamous epithelium of inflammatory skin diseases such as PS, as well as in normal skin epithelium. It is associated with cell proliferation in normal as well as altered epithelium. p53 protein overexpression is an age-related process and significantly associated with sun exposure, especially in NS and PS but also in KA and SCC. Our findings suggest that Ki-67 rate and p53 protein expression reflect the degree of malignancy in the examined cutaneous neoplasms.

Adolescent↗
PubMedDate not supplied

HPV 6-positive giant keratoacanthoma in an immunocompetent patient.

Keratoacanthoma (KA) is a clinically distinct, rapidly growing lesion that generally presents as a solitary crateriform nodule in sun-exposed areas in elderly, fair-skinned individuals. A KA larger than 20-30 mm is referred to as giant keratoacanthoma, a relatively rare lesion especially in young patients. Such lesions grow rapidly with possible destruction of underlying tissues. In addition to ultraviolet exposure, KAs have also been associated with chemical carcinogens, chemical peels, genetic factors, chronic skin conditions that produce scarring, trauma and thermal burns. Immunosuppressed patients, especially after transplantation, also develop KAs. A viral etiology has been suggested but not confirmed. We encountered a case of giant keratoacanthoma (greater than 50 mm in diameter) with induration of underlying structures on the upper lip of a 39-year-old male sailor. The patient reported sudden appearance and rapid enlargement of the lesion in only three weeks. Biopsy of the cutaneous lesion and the characteristic clinical history suggested the diagnosis of keratoacanthoma. Total excision with primary closure of the defect by a nasolabial advancement flap was performed. Histological examination of the tumor mass confirmed the diagnosis of KA with infiltrative growth and perineural invasion. Immunosuppression was excluded by blood analyses, as were HIV, syphilis and hepatitis infections. Only low-risk genital HPV type 6 was detected in the lesion, suggesting a possible cocarcinogenic effect of HPV and UV light in a chronically sun-exposed patient.

Adult↗