Comparative Analysis of External and Internal Radiotherapy- Dependent Plans in Patients with Gynecological Cancer.

Background/Aim: Radiotherapy plays a key role in the treatment of gynecological cancer. Modern radiotherapy techniques with external beams (e-RT) are applied in a broad spectrum of gynecological cancer cases. However, high radiation doses, affecting normal tissue adjacent to cancer, represent the main disadvantage of e-RT regimens. For this reason, brachytherapy (BT), an internal beam-based technique (i-RT), is suggested following e-RT. Our purpose was to compare e-RT plans using volumetric-modulated arc therapy (VMAT) with those using 3D conformal techniques (3D-CRT) and compare BT plans guided by 3D or 2D imaging based on the potential corresponding toxicity levels. Materials and Methods: In this preliminary, non-randomized comparative retrospective study, 15 females suffering gynecological cancer were enrolled. Modern e-RT and i-RT (BT) techniques were applied. Results: Concerning e-RT, D95/D99/rectum 2cc/bladder 2cc and small intestine 2cc were measured and compared; in i-RT, rectum 2cc/bladder 2cc were measured and compared. The median dose to the planning target volume in VMAT was 97.4 Gy compared with 92.9 Gy in 3D-CRT. Τhe rectum received almost 5 Gy less in VMAT compared to 3D-CRT (median of 43.5 Gy vs. 48.6 Gy; p=0.001). In the bladder, dose differences were minimal, while the small intestine received 47.6 Gy in VMAT (p=0.001). Regarding 3D-BT, the rectum received 63.1 Gy compared with 49.9 Gy (p=0.009) in 2D-BT. Concerning the bladder, mean 2D-BT and 3D-BT doses were 71.9 and 65 Gy, respectively, differing non-significantly. Conclusion: VMAT was found to be superior to 3D-CRT, especially in dose distribution, volume coverage and protection of critical organs. Similarly, 3D-BT should be preferred over 2D-BT due to critical advantages.

PTEN Deregulation Mechanisms in Salivary Gland Carcinomas.

Among the tumour suppressor genes that affect critically cell functions and homeostasis, phosphatase and tensin homolog deleted in chromosome 10 (PTEN- gene locus: 10q21) regulates the PI3K/Akt/mTOR signalling pathway. PTEN is deleted, mutated or epigenetically hyper-methylated in a variety of human solid malignancies. Salivary gland carcinomas (SGCs) belong to the head and neck carcinomas (HNCs) super category of solid malignancies. Histo-pathologically, they demonstrate a significant diversity due to a variety of distinct and mixed subtypes. Genetically, they are characterized by a broad spectrum of gene and chromosomal imbalances. Referring specifically to suppressor genes, PTEN deregulation plays a critical role in signaling transduction in the corresponding SGC pre- and malignant epithelia modifying the response rates to potential targeted therapeutic strategies. In the current review, we explored the role of PTEN deregulation mechanisms that are involved in the onset and progression of SGCs.

Impact of Amplified Oncogenes on Salivary Gland Carcinomas.

In normal epithelia, proto-oncogenes regulate critical intra- or intercellular functions, including cell growth and proliferation, apoptosis, and signaling transduction from the cell periphery (extracellular space) to the nucleus mediated by different pathways. Oncogenes are the mutated or amplified forms of the corresponding proto-oncogenes that are crucially involved in cell neoplastic and malignant transformation during carcinogenesis. Salivary gland carcinomas (SGCs) demonstrate a variety of histogenetic types. They are characterized by a broad spectrum of chromosomal and gene alterations. In particular, amplifications in specific genes [human epidermal growth factor receptor 2 (HER2), human epidermal growth factor receptor 4 (HER4), epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), Mouse double minute 2 homolog (MDM2), androgen receptor (AR), programmed death (ligand 1 (PD-L1), neurogenic differentiation factor 2 (NEUROD2), phosphatidylinositol 3,4,5-trisphosphate-dependent RAC exchanger 1 protein (PREX1), cyclin-dependent kinase4/6 (CDK4/6), proline-rich acidic protein 1 (PRAP1), kell antigen system (KEL), glutamate receptor subunit epsilon 2 (GRIN2D), Ewing sarcoma RNA-binding protein 1 (EWSR1), MYC proto-oncogene (MYC)] combined or not with chromosomal numerical imbalances (aneuploidy/ polysomy/monosomy) form different genetic signatures affecting the response to monoclonal antibody-based, oncologicaly targeted regimens. Different SGC histotypes demonstrate specific combinations of mutated/amplified genes that modify their clinicohistological features. In the current molecular review, we present the most important amplified oncogenes and their impact on the biological behavior of SGCS.

Mutational Signatures in Salivary Gland Carcinomas.

Salivary gland carcinomas belong to the head and neck carcinoma super category of malignancies. They are characterized by histopathological diversity and comprise a variety of entities and subtypes. Mucoepidermoid, adenoid cystic and salivary duct carcinomas represent the most prominent malignancies. Concerning their corresponding genetic background, a broad spectrum of gene and chromosomal imbalances has been detected. Point mutations and deletions, amplifications and translocations, combined or not with chromosomal aneuploidy/polysomy/monosomy, create a landscape of specific genetic signatures that affect the biological behavior of these tumors and modify response rates to potential targeted therapeutic strategies. In the current molecular review, we focused on the categorization and description of the most important mutational signatures in salivary gland carcinomas.

Calpain-mediated Mechanoptosis in Breast Adenocarcinoma.

Calpains belong to a family of important calcium-dependent cysteine proteases. They are involved in intracellular processes including cytoskeleton disorganization and substrate proteolysis. They also enhance apoptosis and cell to cell adhesion. Calpains demonstrate also a mechanosensory function in neoplastic and malignant cells due to their implication in mechanoptosis. This is a specific type of apoptotic death induced by strong external mechanical stimuli. Anti-cytoskeleton rigidity inhibition strategies based on calpain induction lead to increased apoptosis of tumor transformed cells. Elevated intracellular calcium concentration mediated by specific receptors and channels activates calpains. In the current molecular review, we explored the role of calpains in calcium-dependent signa transduction pathways in breast adenocarcinoma in conjunction with novel agents that activate their important anti-tumor functions.

DNA Mismatch Repair System Imbalances in Breast Adenocarcinoma.

DNA mismatch repair system (MMR) is considered a leading genetic mechanism in stabilizing DNA structure and maintaining its function. DNA MMR is a highly conserved system in bacteria, prokaryotic, and eukaryotic cells, and provides the highest protection to DNA by repairing micro-structural alterations. DNA MMR proteins are involved in the detection and repair of intra-nucleotide base-to-base errors inside the complementary DNA strand recognizing the recently synthesized strand from the parental template. During DNA replication, a spectrum of errors including base insertion, deletion, and miss-incorporation negatively affect the molecule's structure and its functional stability. A broad spectrum of genomic alterations such as promoter hyper methylation, mutation, and loss of heterozygosity (LOH) in MMR genes including predominantly hMLH1, hMSH2, hMSH3, hMSH6, hPMS1, and hPMS2 lead to their loss of base-to-base error repairing procedure. Microsatellite instability (MSI) refers to the DNA MMR gene alterations that are observed in a variety of malignancies of different histological origins. In the current review, we present the role of DNA MMR deficiency in breast adenocarcinoma, a leading cancer-based cause of death in females worldwide.

Fibroblast Growth Factor-2 (FGF-2) Expression in Pterygia Using Cell Spot Arrays.

Fibroblast growth factor (FGF) is a main regulator of cell differentiation, cell migration and angiogenesis in normal and abnormal conjunctiva epithelia, but specific mechanisms of its aberrant expression are yet to be investigated. In the present study, we investigated FGF-2 protein expression within several pterygia. Using a liquid-based cytology assay, we obtained cell specimens from pterygia and healthy tissues directly from patients. A combination of immunocytochemistry followed by digital image analysis showed significant overexpression of FGF-2 in all the examined pterygia. In 30/60 (50%) cases there were high levels of staining intensity, whereas in the remaining 30/60 (50%) cases there were moderate levels of expression. FGF-2 levels of the control group were significantly lower in comparison with the pterygia group. There was no significant correlation between FGF-2 levels and either sex or location of the pterygium. FGF-2 levels had a significant correlation with morphological characteristics of the pterygia. More specifically, FGF-2 levels were significantly higher in the pterygia with a fleshy morphology. Interestingly, recurrent lesions demonstrated high expression levels. An overexpression of FGF-2 has been observed frequently in pterygia, where it may play a crucial role in determining the lesion's progression. FGF-2 upregulation correlates with the morphology of pterygia and its tendency to recur. Cell spot analysis based on liquid-based cytology is a simple, yet effective, method for detecting a broad spectrum of protein markers and could be useful in analyzing potential pterygia patient samples.

Secretory Phospholipase A2 Digital Expression Analysis in Colon Adenocarcinoma.

BACKGROUND/AIM: Phospholipases A2 represent a family of enzymes that regulate the metabolism of phospholipids by hydrolyzing them into fatty acids. Secretory phospholipase A2 (SPLA2) catalyzes the calcium-dependent 2-acyl groups hydrolysis to produce 3-sn-phosphoglycerides. This study aimed to investigate SPLA2 expression in colon adenocarcinoma (CA). MATERIALS AND METHODS: Thirty (n=30) formalin-fixed, paraffin-embedded primary CA tissue sections were used and analyzed. Immunohistochemistry was performed using an anti-SPLA2 antibody. Digital image analysis was also implemented for evaluating objectively the corresponding protein expression levels. RESULTS: Increased SPLA2 protein expression (high & moderate immunostaining levels) was observed in 23/30 (76.6%) cases, whereas 7/30 (23.4%) CA tissues demonstrated low protein levels. High expression levels were detected in 9/30 (30%) cases. SPLA2 overall expression was strongly associated with tumor diameter (p=0.004), whereas other statistically significant associations were not observed (stage: p=0.971, inflammatory infiltration: p=0.795; carcinoma location: p=0.340; differentiation grade: p=0.748; sex: p=0.369; ulceration: p=0.433). CONCLUSION: SPLA2 over-expression is observed in significant subsets of CAs correlating with advanced tumor growth progression (increased diameter). SPLA2 seems to influence endogenous cell responses by its crucial enzymatic activity and can potentially be a biomarker for monitoring CA patients.

Reconstructing carcinoma of the lip commissure and buccal mucosa: an oncosurgical alternative approach.

PURPOSE: To describe a new technique of surgical treatment of the lip commissure or buccal mucosa carcinomas, where we use local flaps (skin, buccal mucosa) of the sliding type. METHODS: According to the current technique, the ectomy ranges horizontally and in a cuneiform shape towards the side of the buccal cavity, and in the whole thickness of the layer (skin - mucosa), where the neoplastic focus is enclosed. RESULTS: The difference in our technique consists of the following: To the vertical bi-cuneiform part of the wound a horizontal cuneiform part (with the top showing upwards) is added, with extent and width analogous to those of the cancerous injury (tri-cuneiform ectomy). The width of the gap across its horizontal part is larger on the side of the mucosa (continuous line), compared to the one along the side of the skin (punctuated line), since the mucosa, as a more versatile tissue, can be sutured easily, in contrast to the buccal skin, which is of greater thickness and shows lack of versatility, so that it can be pulled on with difficulty in order to be sutured. The planning of the injury, according to our described technique, facilitates the broad ectomy of the intraoral injuries in the area of the lip commissure and the buccal mucosa, with immediate suture of the flaps (buccal and skin gap), and the occlusion of the wound by primary intention. CONCLUSIONS: Using this specific technique, in the cases of extended injuries infiltrating the skin or the subcutaneous tissue, the harming use of transposition (sliding or free) flaps is avoided.

Impact of PD-L1 Protein Expression on Renal Cell Carcinoma Histo-differentiation.

BACKGROUND/AIM: Renal cell carcinoma (RCC) comprises a variety of pathological entities. Many RCCs are aggressive, demanding efficient targeted and immunetherapeutic strategies. Programmed cell death ligand-1 (PD-L1) is expressed mainly in hematopoietic cells and also in epithelial cells. The aim of this study was to correlate PD-L1 protein expression in a series of RCC tissues with their histo-pathological features. MATERIALS AND METHODS: One hundred (n=100) archival, formalin-fixed and paraffin-embedded RCC tissue specimens were analysed by immunohistochemistry. Conventional tumor proportion score (TPS) qualitative assay was applied for evaluating protein expression levels. RESULTS: Based on the TPS evaluation, 8 (8%) cases were characterized as positive, and the rest of them (n=92; 92%) as negative. A progressive increase in PD-L1 positivity was significantly associated with the differentiation grade of the examined malignancies (p=0.001). CONCLUSION: Although PD-L1 over-expression is detected in low rates in RCCs, its correlation with differentiation grade should be considered as a factor for discriminating sub-groups of patients with specific histo-pathological features eligible for targeted anti-PD-L1 immunotherapy strategies.

Micro-RNAs signatures in papillary thyroid carcinoma.

Among biomarkers that should be useful for a molecular discrimination of patients regarding treatment strategies and prognosis in solid malignancies, novel micro-RNAs (miRs) are under investigation. Quite recently, miRs are considered very promising and significant genetic markers for categorizing patients by their molecular characteristics, as well as extending their complicated genetic signatures. miRs are short, non-coding RNAs consisting of 20-25 nucleotides located at intra- or inter-gene regions. Functional miRs mediate a positive regulation of posttranscriptional gene silencing. Their deregulation in cancer cells due to genetic (e.g., mutations, translocations), epigenetic (e.g., DNA hyper-methylation of tumor suppressor genes, extensive genomic DNA hypo-methylation, aberrant histone modification patterns) and transcriptional alterations lead to a loss of miRs-mediated repression of target mRNA. Interestingly, a biphasic role of miRs in cancers of different histogenetic origin has been confirmed. In some of them, their upregulation is correlated with an increased oncogenic activity, whereas in others, the same miR type acts as a suppressor agent. Thyroid carcinoma comprises different histological subtypes, such as papillary thyroid carcinoma (PTC), follicular thyroid carcinoma (FTC), anaplastic thyroid cancer (ATC), and medullary thyroid carcinoma. In the current molecular review, we explored the role of a specific fraction of miRs in PTC subtype by categorizing them according to their up- or down-regulation status.