NEAT1 Is a Novel Oncogenic LncRNA and Correlated with miR-143 in Pediatric Oligodendrogliomas.

INTRODUCTION: The noncoding RNAs (ncRNAs) play a role in biological processes of various cancers including gliomas. The majority of these transcripts are uniquely expressed in differentiated tissues or specific glioma types. Pediatric oligodendroglioma (POG) is a rare subtype of diffuse glioma and accounts for <1% of pediatric brain tumors. Because histologically POG resembles adult OG, the same treatment is applied as adults. However, the significance in predicting outcomes in POG patients is unclear. In this study, we aimed to investigate the prognostic significance of expression -profiles of microRNA (miRNA) and long noncoding RNA -(LncRNA) in POGs. METHODS: We investigated the levels of 13 known miRNAs and 6 LncRNAs in tumor samples from 9 patients with primary POG by using RT-PCR and analyzed their association with outcomes. RESULTS: The expression levels of miR-21, miR-106a, miR-10b, and LncRNA NEAT1 were higher, and the expression level of miR-143 was lower in POG tissues compared with normal brain tissues (p = 0.006, p = 0.032, p = 0.034, p = 0.002, and p = 0.001, respectively). High levels of NEAT1 and low expression of miR-143 were associated with decreased probability of short disease-free survival (p = 0.018 and p = 0.022, respectively). DISCUSSION: NEAT1 and miR-143 levels could serve as reciprocal prognostic predictors of disease progression in patients with POG. New treatment models to regulate the expression levels of NEAT1 and miR-143 will bring a new approach to the therapy of POG.

Olea europaea Leaf Extract Improves the Efficacy of Temozolomide Therapy by Inducing MGMT Methylation and Reducing P53 Expression in Glioblastoma.

Unmethylated O6-methylguanine-DNA-methyltransferase (MGMT) promoter leads to Temozolomide (TMZ) resistance in most of the glioblastoma multiforme (GBM) patients. We previously investigated the synergistic effect of Olea europaea leaf extract (OLE) on TMZ cytotoxicity through modulating microRNA expression. To date, knowledge about the effect of OLE on MGMT methylation is insufficient. The aim of the current study was to evaluate the potential modulating effect of OLE on the TMZ response of GBM tumors through MGMT methylation. Exposure to 1 mg/mL OLE caused a significant induction of CpG island methylation in the MGMT gene using Methyl quantitative PCR assay (P < 0.001). In WST-1 analysis, the use of 350 µM TMZ plus 1 mg/mL OLE significantly increased the TMZ response of MGMT unmethylated cells (P = 0.003). Using the comet assay, the impact of 1 mg/mL OLE plus 350 µM TMZ on the formation of DNA strand breaks was significantly higher than that of 450 µM TMZ alone (P < 0.001) and Western blot analysis revealed that, when cells are treated with 1-mg/mL OLE, the total p53 protein levels tended to decrease. The results presented in this study uniquely demonstrated that OLE synergistically increased the TMZ response of GBM tumors by regulating MGMT gene methylation and p53 expression. However, further studies to validate our findings are required.

Leptomeningeal dissemination and vertebral bone involvement in a child with pilocytic astrocytoma.

In low-grade glioma, metastasis is rarely seen. Few cases of leptomeningeal dissemination have been reported in children. Vertebral bone metastasis has not been reported so far. Herein is described the case of a pediatric patient with the diagnosis of pilocytic astrocytoma, and leptomeningeal dissemination detected at the time of diagnosis, who then received radiotherapy and chemotherapy upon development of vertebral bone metastasis during treatment.

Immunohistochemical expression of human epidermal growth factor receptor (HER)-4 and prognosis in patients with metastatic breast cancer.

PURPOSE: The clinical value of HER4 - a cell surface receptor that belongs to the human epidermal growth factor receptor family - for predicting survival outcomes in patients with breast cancer remains controversial. Herein, we sought to investigate the prognostic significance of HER4 immunohistochemical expression with respect to progression-free survival (PFS) and overall survival (OS) in Turkish patients with metastatic breast cancer (MBC). METHODS: MBC patients (N=45; mean age=50.5±12.7 years) were consecutively enrolled between 2000 and 2006 in the Department of Oncology at the Uludag University Medical Center, Bursa, Turkey. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded sections. The predictive value of HER4 expression was investigated by multivariate analysis after allowance for potential confounders. RESULTS: The mean PFS in the study participants was 11.35 months (range:1-50), whereas the median OS was 22.18 months (range:1-76). The mean PFS in patients with a HER4 immunohistochemical score of 0, 1+, 2+, and 3+ was 11.0 ± 4.8, 11.3 ± 7.7, 11.7 ± 8.1, and 10.4 ± 7.4 months, respectively (p=0.99) . The mean OS in patients with a HER4 score of 0, 1+, 2+, and 3+ was 13.3 ± 6.8, 25.6 ± 10.8, 22.9 ± 10.7, and 13.5 ± 9.9, months, respectively (p=0.44). The results of multivariate Cox regression analysis indicated that the presence of visceral metastases was the only independent prognostic factor for both OS (HR=3.01, 95% CI=1.56-3.99, p <0.01) and PFS (HR=2.91, 95% CI=1.51-3.78, p <0.01). CONCLUSION: HER4 immunohistochemical expression is not an independent predictor of OS and PFS in Turkish MBC patients.

Prognostic impact of tumor lymphocytic infiltrates in patients with breast cancer undergoing neoadjuvant chemotherapy.

PURPOSE: The presence of a pronounced tumor lymphocytic infiltrate (TLI) is deemed to reflect the presence of an immunoinflammatory response against the tumor and may thus have prognostic significance. We investigated the prognostic value of TLI detected in pathological specimens collected following neoadjuvant chemotherapy (NACT) in patients with breast cancer. METHODS: 100 consecutive patients with breast cancer (mean age 47.8±11.4 years) who were scheduled to undergo anthracycline-and/or taxane-containing NACT were enrolled. Specimens collected after NACT were scored with the 4-point Klintrup scoring criteria for the presence of TLI. RESULTS: 60 patients had low-grade TLI and 40 high-grade TLI. Comparison of the patient population according to low-grade vs high-grade TLI revealed statistically significant difference both in terms of disease-free survival (DFS) (log rank-4.28, p<0.05) and overall survival (OS) (log rank=3.96, p<0.05), with high-grade TLI patients showing a better prognosis. Multivariate Cox regression analysis identified postoperative tumor size and low-grade TLI as the two main independent adverse prognostic factors. CONCLUSION: High-grade TLI may interfer with tumor growth and can represent a favorable prognostic factor in women with breast cancer undergoing NACT.

Neoadjuvant chemotherapy-induced changes in immunohistochemical expression of estrogen receptor, progesterone receptor, HER2, and Ki-67 in patients with breast cancer.

PURPOSE: The impact of neoadjuvant chemotherapy (NACT) on immunohistochemical markers in breast cancer specimens remains controversial. We designed the current study to investigate the potential changes in estrogen receptor (ER), progesterone receptor (PR), HER2, and Ki-67 expression before and after NACT in a cohort of Turkish patients with breast cancer. METHODS: This research was designed as a prospective, observational study of 100 consecutive patients with breast cancer (mean age 47.8±11.4 years) who were scheduled to undergo anthracycline- and/or taxane-containing NACT before attempting cytoreductive surgery at the Department of Oncology of the Uludag University Medical Center, Bursa, Turkey. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded specimens. RESULTS: Changes in immunohistochemical markers before and after NACT were only significant for HER-2 and Ki- 67. More specifically, the number of HER-2-positive specimens decreased from 21 before NACT to 8 after NACT (p<0.001). Similarly, the number of tumor samples positive for Ki-67 decreased significantly from 65 to 24 after NACT (p<0.001). Mean pre- and post-treatment tumor grades of differentiation before and after NACT were 2.56 ± 0.67 and 2.37±1.07, respectively (p<0.05). We did not find any significant associations between baseline ER, PR, HER2, and Ki-67 expression with both overall survival (OS) and disease- free survival (DFS). CONCLUSION: Our study suggests that NACT reduces the expression of HER2 and Ki-67 in breast cancer specimens. The significance of NACT-induced changes in the immunohistochemical expression of HER2 and Ki-67 in patients with breast cancer should be further studied in future translational and clinical research.

microRNA expression pattern modulates temozolomide response in GBM tumors with cancer stem cells.

Temozolomide (TMZ) is widely used to treat glioblastoma multiforme (GBM). Although the MGMT gene methylation status is postulated to correlate with TMZ response, some patients with a methylated MGMT gene still do not benefit from TMZ therapy. Cancer stem cells (CSCs) may be one of the causes of therapeutic resistance, but the molecular mechanism underlying this resistance is unclear. microRNA (miRNA) deregulation has been recognized as another chemoresistance modulating mechanism. Thus, we aimed to evaluate the miRNA expression patterns associated with chemoresistance that is dependent on the CSC status in GBM tumors to identify therapeutic biomarkers. CSCs were identified in 5 of 20 patients' tumor tissues using magnetic separation. CSC (+) tumors displayed a significant induction of CpG island methylation in the MGMT gene promoter (p = 0.009). Using real-time reverse transcription polymerase chain reaction (qRT-PCR), 9 miRNAs related to GBM (mir-181b, miR-153, miR-137, miR-145, miR-10a, miR-10b, let-7d, miR-9, and miR-455-3p), which are associated with cell cycle and invasion was analyzed in tumor samples. Low miR-181b and high miR-455-3p expression levels were detected (p = 0.053, p = 0.004; respectively) in CSC (+) tumors. Analysis revealed a significant correlation between miR-455-3p expression and Smad2 protein levels as analyzed by immunohistochemistry in CSC (+) tumors (p = 0.002). Thus, miR-455-3p may be involved in TMZ resistance in MGMT methylated CSC (+) GBM patients. Further studies and evaluations are required, but this miRNA may provide novel therapeutic molecular targets for GBM treatment and new directions for the development of anticancer drugs.

Expression status of let-7a and miR-335 among breast tumors in patients with and without germ-line BRCA mutations.

The genetic factors of cancer predisposition remain elusive in the majority of familial and/or early-onset cases of breast cancer (BC). This type of BC is promoted by germ-line mutations that inactivate BRCA1 or BRCA2. On the other hand, recent studies have indicated that alterations in the levels of miRNA expression are linked to this disease. Although BRCA1 and BRCA2 gene mutations have been reported to commonly lead to alterations in genes that encode cancer-related proteins, little is known regarding the putative impact of these mutations on noncoding miRNAs. In the present study, we aimed to determine whether miRNA dysregulation is involved in the pathogenesis of BRCA-mutated BC. An expression analysis of 14 human miRNAs previously shown to be related to BC diagnosis, prognosis, and drug resistance was conducted using tissues from 60 familial and/or early-onset patients whose peripheral blood samples had been screened for BRCA1 and BRCA2 mutations through sequence analysis. Let-7a and miR-335 expression levels were significantly downregulated in the tumors of patients with a BRCA mutation compared with those of patients without a BRCA mutation (P = 0.04 and P = 0.02, respectively). Our results defined the associations between the expression status of let-7a and miR-335 and BRCA mutations. The expression analysis of these miRNAs might be used as biomarkers of the BRCA mutation status of early-onset and/or familial BC.

Histopathological Features Predicting Neuroendocrine Morphology in Primary Breast Tumors: A Retrospective Analysis.

Objective: Neuroendocrine neoplasms of primary breast tumors are rare compared to locations, such as the respiratory system and gastrointestinal system, where they are frequently observed. The diagnostic criteria for primary neuroendocrine tumors of the breast have been changed since first description. Morphological and immunohistochemical features helpful in their diagnosis, which vary due to the heterogeneous nature of these tumors, are highlighted in this retrospective study. The purpose was to determine specific histopathological features that can identify neuroendocrine morphology in primary breast tumors. Materials and Methods: Cases diagnosed with invasive breast carcinoma from resection materials in a single center between 2011 and 2022 and in which neuroendocrine markers were investigated were included. Demographic information, initial histopathological diagnosis, presence of tumor in another organ, tumor location, size and surgical details of the cases were obtained from the hospital database and pathology reports. The slides were re-evaluated in terms of tumor growth pattern, cribriformity, tubule formation, nuclear features, prominence of nucleoli, palisading and basal location of nuclei, presence of grooves, cytoplasmic features and evidence of cytoplasmic border. Results: The presence of basally located nuclei, absence of tubule formation, inconspicuous nucleoli, fine nuclear chromatin, granular cytoplasm and inconspicuous cytoplasmic borders were frequent findings in tumors with neuroendocrine features (p<0.05). These features may help differentiate primary breast tumors with neuroendocrine features from other breast carcinomas. Conclusion: The histopathological features that are different from the specific features seen in classical neuroendocrine tumors, the absence of specific clinical and radiological findings, the inability to study neuroendocrine markers in every laboratory and the need to prove that the breast tumor is not a metastasis all create diagnostic difficulties for primary breast neuroendocrine neoplasms. We believe that the results of this study may help diagnose and identify more specific histomorphological features that help determine neuroendocrine morphology in primary breast tumors.

Investigation of the Relationship Between Tumor Microenvironment and Prognostic Parameters in Invasive Breast Carcinomas of No Special Type: A Retrospective Analysis.

OBJECTIVE: The tumor microenvironment is a heterogeneous and constantly changing territory that plays an active role in tumor formation and progression. It constantly interacts with tumor cells, plays an active role in tumor development, and even appears as a parameter of prognostic importance, and the importance of the tumor microenvironment in breast cancer has been emphasized by recent studies. In this study, we aimed to retrospectively evaluate the relationship between the tumor microenvironment and prognostic parameters in invasive breast carcinomas of no special type. MATERIAL AND METHODS: A total of 271 cases diagnosed as invasive breast carcinoma of no special type from resection materials in our center between 2007 and 2015 were included in the study. Hematoxylin-eosin stained slides with a thickness of 4-5 micrometers were evaluated in terms of tumor infiltrating lymphocytes, peritumoral and intratumoral desmoplastic reaction, intratumoral and peritumoral tumor budding, stromal features, and tumor growth pattern. RESULTS: When parameters related to the tumor microenvironment were compared with other prognostic parameters, there was a significant relationship between TILs and tumor grade, size, stage, immunohistochemical subgroup and Ki-67 proliferation index. A significant relationship was detected between intratumoral stromal reaction and tumor grade, size, molecular subgroup and the Ki-67 proliferation index (p < 0.05). When stroma and other prognostic parameters were compared, tumors with desmoplastic stroma had higher grades and higher Ki-67 proliferation indexes, and they were observed more frequently in the triple negative molecular subgroup. CONCLUSION: We believe that including parameters related to tumor microenvironment in breast cancer reports, which hold a prognostic and predictive importance, will contribute to patient management. Considering the fact that these can be easily evaluated from routinely used hematoxylin-eosin stained slides, this does not cause additional costs or excessive time loss.

Differential diagnosis of primary mesenchymal neoplasms of the breast.

OBJECTIVE: While the majority of breast neoplasms originate from epithelial cells, a rare part of them originate from mesenchymal breast tissue. This study aims to present the histomorphological and clinicoradiological features of our series of primary mesenchymal breast tumors and to discuss the features of these tumors in light of the literature. MATERIALS AND METHODS: Cases diagnosed as primary mesenchymal breast tumor in breast resection materials evaluated in our center between 2010 and 2023 were included. RESULTS: Of the 26 tumors included, 57.7% were diagnosed as benign and 42.3% as malignant mesenchymal tumor. Cases diagnosed as benign mesenchymal tumor were hemangioma, lipoma, extra-abdominal fibromatosis, leiomyoma, angiofibroma, lipomatosis, benign fibrous histiocytoma and granular cell tumor. Histopathological study results were compatible with angiosarcoma in 5 (45.4%), undifferentiated sarcoma in 3 (27.3%), myxofibrosarcoma in 2 (18.2%) cases and rhabdomyosarcoma in 1 (9.1%) case. CONCLUSION: Primary breast sarcomas are rarely seen compared to benign mesenchymal tumors and constitute less than 0.1% of all malignant breast tumors. When histomorphological findings suggestive of a mesenchymal tumor are observed in breast specimens, sufficient sampling should be performed to exclude a possible phyllodes tumor, and clinicoradiological findings should be examined to exclude the possibility of a metastasis.

Prognostic factors of tumefactive demyelinating lesions and differential features for multiple sclerosis in etiology.

BACKGROUND: Many different pathologies may underlie tumefactive demyelinating lesions. Identifying clinical and radiologic distinguishing features before pathologic examination is essential for diagnosis and treatment. In this study, we aimed to determine the clinical and radiologic features affecting the etiology and disease course of patients with tumefactive lesions (TDL). MATERIALS AND METHODS: We included 35 clinicoradiologically or histologically diagnosed TDL patients in our center over 11 years. Patient records were retrospectively evaluated and recorded. Clinical features, cerebral neuroimaging, and histologic biopsy preparations, if any, were assessed by three independent neurologists, two neuroradiologists, and two pathologists at admission and follow-up, respectively. RESULTS: The mean age of patients with TDL was 40.02±14.40 years. Symptom onset was 15 (1-365) days. The most common complaints at initial presentation were hemiparesis or hemiplegia, sensory complaints, and cognitive impairment (aphasia or apraxia). The lesions were most commonly localized in the frontal lobe (42.9 %). Mass effect was 17.1 %, edema 60 %, diffusion restriction 62.1 %, and contrast enhancement 71.9 % (mostly ring-shaped (68.8 %)) on MR images. Acute onset and OCB type-2 positivity were associated with MS diagnosis. On the other hand, CSF protein levels above 45 mg/dL were found to be related to non-MS etiologies. Only the predominance of aphasia or apraxia at onset was a risk factor for early high disability (EDSS>4; 3rd month). Subacute-chronic onset, being older than 40 years, or having brainstem symptoms at onset were independent risk factors for late high disability (2nd year). CONCLUSION: Acute onset or OCB type 2 positivity is a clue for early diagnosis of MS, while elevated CSF protein is a clue for demyelinating diseases other than MS. Presentation with cognitive dysfunction at onset is an independent risk factor for early disability, while age above 40 years, subacute-chronic presentation and brainstem findings at presentation are independent risk factors for late disability.

Crystal storing histiocytosis forming a mass lesion in temporal lobe.

Crystal storing histiocytosis is a disorder characterized by local or diffuse infiltration of histiocytes containing crystalline inclusions. This entity has been reported in several organs, however the involvement of the central nervous system (CNS) is extremely rare and to date only 7 cases of crystal storing histiocytosis (CSH) of CNS have been reported in the English literature. More than 90% patients with CSH had an underlying lymphoproliferative or plasma cell disorders, especially multiple myeloma, lymphoplasmacytic lymphoma or monoclonal gammopathy. Radiologically and intraoperatively, CSH may mimic an infectious process or neoplasm, hence its histopathological confirmation is important to facilitate appropriate treatment. In this report, we describe an additional case of crystal storing histiocytosis in a 48 year old female who presented with a mass lesion in the right temporal lobe of the cerebrum.

Primary Mucinous Cystadenocarcinoma of the Breast: Clinicopathological Analysis of a Case and Difficulties Encountered in a Biopsy.

Background. With <40 case reports published in the English literature, mucinous cystadenocarcinoma of the breast is quite rare compared to its counterparts in the ovary, pancreas, and appendix. The purpose of this case report is to enrich scientific data by sharing the clinicopathological features of this new and extremely rare entity and present possible difficulties encountered in the biopsy materials. Case Report. A 34-year-old female patient presented with the complaint of white discharge from her left nipple lasting 8 months. Physical and radiological examination of the patient revealed a mass in the lower quadrant of the left breast and tru-cut biopsy was performed. The diagnosis of invasive breast carcinoma of no special type was reported. After neoadjuvant chemotherapy, left subcutaneous mastectomy and left sentinel lymph node biopsy were performed. Microscopic evaluation of the mastectomy material revealed a tumor consisting of stratified columnar cells with basally located nuclei and intracytoplasmic mucin, showing papillary structures and tufting toward the lumen. Peripheral myoepithelial cells were not identified with p63 and calponin immunohistochemistry. The diagnosis of mucinous cystadenocarcinoma was given through histomorphological and immunohistochemical evaluations. Conclusion. Clarifying unknown points about this rare malignancy of the breast and understanding the tumor biology is possible through evaluation of case reports. For this purpose, our case of primary mucinous cystadenocarcinoma is presented and its clinicopathological features are briefly discussed.

Hemorrhagic presentation of previously silent brain tumors.

INTRODUCTION AND OBJECTIVES: Acute presentation with intracranial hemorrhage owing to a previously silent brain tumor (BT) is rare. Although any BT can bleed, the frequency and type of bleeding varies across tumor types. MATERIALS AND METHODS: We aimed to retrospectively review our experience with 55 patients with BTs presenting with ICH. RESULTS: Signs of increased intracranial pressure were the most common symptoms. The temporal lobe was the most common lesion site (n=22). Hemorrhages were mainly confined to the tumor margins (HCTs) (n=34). Extensive intraparenchymal hemorrhages (EIHs) were mainly associated with moderately/severely decreased levels of consciousness (LOCs) (n=15/16). High-grade glioma (HGGT) (n=25) was the leading pathological diagnosis followed by metastasis (MBT) (n=16/55). The hemorrhage type was associated with the pathological diagnosis of the tumor. Patients with HGGT (n=19/25) and MBT (n=9/16) mainly presented with HCTs, whereas low-grade gliomas (LGGT) primarily caused EIHs (n=6/7). CONCLUSIONS: Hemorrhagic presentation is a rare occurrence in BTs. Among all, MBT and HGGT are responsible for majority of the cases. Importantly, despite their relatively benign characteristics, LGGTs mainly result in extensive parenchymal destruction once they bleed. Maximum surgical resection of hemorrhagic BTs and decompression of the affected brain regions followed by histological confirmation of the diagnosis should be the main goals of treatment in cases with hemorrhagic BTs.

Metastatic Neoplasms to the Breast.

OBJECTIVE: When the clinical presentation is related to the metastatic mass and a radiologically solitary tumor focus is detected, especially in cases where clinical information is not taken into account or is insufficient, if a possible metastatic neoplasia is not kept in mind then it is possible to evaluate the tumor as a primary breast neoplasm. In this study, it is aimed to present our cases of non-hematopoietic metastatic neoplasms and to evaluate the clinicopathological features that may aid in distinguishing metastatic from primary neoplasms. MATERIAL AND METHODS: This study includes cases diagnosed with metastatic non-hematopoietic breast neoplasm in breast resection materials in our center, between the years 2010-2023. All cases were analyzed retrospectively by evaluating clinicopathological features. RESULTS: Of the 15 subjects included in the study, 11 (73%) were female and 4 (27%) were male. The mean age of the patients were 46.9 ranged from 22 to 63 years. The most frequent metastatic malignancy was carcinoma (60%), followed by melanoma (33%) and sarcoma (7%). Of the 9 patients with metastatic carcinoma, the primary tumor originated from the lungs in 4, from gastrointestinal system in 2, female genital tract in 2, and kidney in 1 patient. Sarcoma diagnosis was given in a single patient and the histology was a leiomyosarcoma originating from kidney. CONCLUSION: A careful histomorphological and immunohistochemical evaluation and a detailed examination of the clinicoradiological data are critical to establish the right course in patient management, treatment plan and to correctly predict the prognosis.

Surgical Management of Brain Tumors in Infants Under One Year of Age.

AIM: To comprehensively analyze clinical presentation, diagnosis, and management approaches of brain tumors in infants under one year of age. MATERIAL AND METHODS: We conducted a retrospective analysis of clinical data retrieved from medical records of infants who underwent surgical treatment for intracranial mass lesions at our institution from January 2006 to December 2016. The data encompassed parameters such as age at diagnosis, symptoms, tumor location, histology, surgical procedures, adjuvant treatment, and survival outcomes. Cases involving dermoid, epidermoid cysts, and other skull-based lesions were excluded from the analysis. RESULTS: Our analysis identified twenty-three cases of brain tumors diagnosed within the first year of life, comprising 14 boys and 9 girls. The median age at diagnosis was 8.2 months, and the most common presenting symptoms were nausea and vomiting, as well as head circumference abnormalities. Successful gross total resection was achieved in 75.8% of patients, with choroid plexus papilloma being the most frequently encountered histopathological diagnosis. Eight patients received adjuvant chemotherapy, while one patient underwent salvage radiotherapy. CONCLUSION: The treatment of brain tumors in infants during their first year of life presents significant challenges. The affected patients exhibit diverse tumor pathologies occurring at various locations within the brain. Further research is warranted to establish optimal treatment options for this specific population.

Diabetes Mellitus-Mediated MALAT1 Expression Induces Glioblastoma Aggressiveness.

AIM: To describe the role of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in glioblastoma (GB) progression in patients concurrently diagnosed with diabetes mellitus (DM). MATERIAL AND METHODS: Formalin-fixed paraffin-embedded (FFPE) tumor samples of 47 patients diagnosed with GB only and 13 patients diagnosed with GB and DM (GB-DM) were enrolled in this study. Data for p53 and Ki67 immunohistochemical staining of the tumors and blood HbA1c levels of patients with DM were retrospectively collected. MALAT1 expression was assessed using quantitative real-time polymerase chain reaction. RESULTS: The coexistence of GB and DM induced the nuclear expression of p53 and Ki67 compared with GB only. MALAT1 expression was higher in GB-DM tumors than in GB only tumors. The expression of MALAT1 and HbA1c levels were positively correlated. Additionally, MALAT1 was positively correlated with tumoral p53 and Ki67. The disease-free survival of patients with GB-DM with high MALAT1 expression was shorter than that of those diagnosed with GB only and with a lower MALAT1 expression. CONCLUSION: Our findings suggest that one of the mechanisms of the facilitating effect of DM on GB tumor aggressiveness is via MALAT1 expression.

A Multicenter Study of Genotype Variation/Demographic Patterns in 2475 Individuals Including 1444 Cases With Breast Cancer in Turkey.

Objective: Breast cancer (BC) is the most common cancer type in women and may be inherited, mostly in an autosomal dominant pattern. The clinical diagnosis of BC relies on the published diagnostic criteria, and analysis of two genes, BRCA1 and BRCA2, which are strongly associated with BC, are included in these criteria. The aim of this study was to compare BC index cases with non-BC individuals in terms of genotype and diagnostic features to investigate the genotype/demographic information association. Materials and Methods: Mutational analyses for the BRCA1/BRCA2 genes was performed in 2475 individuals between 2013-2022 from collaborative centers across Turkey, of whom 1444 with BC were designated as index cases. Results: Overall, mutations were identified in 17% (421/2475), while the percentage of mutation carriers in cases of BC was similar, 16.6% (239/1444). BRCA1/BRCA2 gene mutations were detected in 17.8% (131/737) of familial cases and 12% (78/549) of sporadic cases. Mutations in BRCA1 were found in 4.9%, whereas 12% were in BRCA2 (p<0.05). Meta-analyses were performed to compare these results with other studies of Mediterranean-region populations. Conclusion: Patients with BRCA2 mutations were significantly more common than those with BRCA1 mutations. In sporadic cases, there was a lower proportion with BRCA1/BRCA2 variants, as expected, and these results were consistent with the data of Mediterranean-region populations. However, the present study, because of the large sample size, revealed more robust findings than previous studies. These findings may be helpful in facilitating the clinical management of BC for both familial and non-familial cases.

The promoter hypermethylation status of GATA6, MGMT, and FHIT in glioblastoma.

Glioblastoma (GBM) is an aggressive and lethal cancer, accounting for the majority of primary brain tumors in adults. GBMs are characterized by large and small alterations in genes that control cell growth, apoptosis, angiogenesis, and invasion. Epigenetic alterations also affect the expression of cancer genes, either alone or in combination with genetic mechanisms. The current evidence suggests that hypermethylation of promoter CpG islands is a common epigenetic event in a variety of human cancers. A subset of GBMs is also characterized by a locus-specific and genome-wide decrease in DNA methylation. Epigenetic alterations are important in the molecular pathology of GBM. However, there are very limited data about these epigenetic alterations in GBM. Alterations in promoter methylations are important to understand because histone deacetylases are targets for drugs that are in clinical trial for GBMs. The aim of the current study was to investigate whether the promoter hypermethylation of putative tumor suppressor genes was involved in GBM. We examined the methylation status at the promoter regions of GATA6, MGMT, and FHIT using the methylation-specific polymerase chain reaction in 61 primary GBMs. Our results reveal that there is no promoter hypermethylation of FHIT in the examined GBM tissue specimens. In contrast, the promoter hypermethylation of GATA6 and MGMT was detected in 42.8 and 11.11% of GBMs, respectively. The frequency of MGMT promoter hypermethylation was low in the group of patients we evaluated. In conclusion, our study demonstrates that promoter hypermethylation of MGMT is a common event in GBMs, whereas GATA6 is epigenetically affected in GBMs. Furthermore, inactivation of FHIT by epigenetic mechanisms in GBM may not be associated with brain tumorigenesis.