Comparison of immunophenotypes of primary breast carcinomas and multiple corresponding distant metastases: an autopsy study of 25 patients.

Phenotypical change in metastatic breast carcinoma has widely been accepted as an inherent biological feature rather than technical fault. We analyzed the immunohistochemical phenotype and histopathological features of 25 primary breast carcinomas and 90 corresponding distant metastases in 23 organs retrospectively. Histological slides were reviewed for prognostic and predictive factors. Overall, metastases were more similar to each other and often differed from the primary tumor. We created a 3-step grouping system based on the localization of metastases. Regions: tumors metastasizing to the abdominal region were likely to lose ER (p = 0.002); we detected loss of PR in metastases to the thorax (p = 0.039) and abdomen (p < 0.001). Organ systems: loss of ER and PR was observed in metastases to the gastrointestinal system (p = 0.026 and p = 0.001, respectively), in the respiratory system only the loss of PR was significant (p = 0.05). Individual organs: the primaries were likely to lose the hormone receptors in liver metastases (ER p = 0.026; PR p = 0.004). In lung metastases only loss of PR was apparent (p = 0.049). We did not observe significant change in HER2 status, regarding Ki67 change occurred only in bone metastases compared to the primary (p = 0.048). 7/25 patients' distant metastases had heterogeneous immunoprofiles. The later the metastasis was discovered the more likely it had a differing IHC profile compared to the primary tumor, patients who had longer OS had a higher chance to develop a discordant metastasis. Immunoprofile of metastases may differ from primary breast cancer and from each other, probably resulting in different response to therapy.

Comparative analysis of new peptide conjugates of antitubercular drug candidates-Model membrane and in vitro studies.

Novel peptide conjugates of two antitubercular drug candidates were synthesised and characterised using new tuftsin peptide derivative (OT14) as carrier moiety. As antitubercular drug candidates two pyridopyrimidine derivatives, TB803 (2-allylamino-4-oxopyrido[1,2-a]pyrimidine-3-carbaldehyde) and TB820 (4-oxo-2-(pyrrolidin-1-yl)-pyrido[1,2-a]pyrimidin-3-carbaldehyde) inhibiting vital enzyme of Mycobacterium tuberculosis were applied. Membrane affinity of the compounds TB803 and TB820 and their peptide conjugates was evaluated using experimental lipid mono- and bilayer models. Penetration ability was assessed tensiometrically from Langmuir monolayer study and applying quartz crystal microbalance for the supported lipid bilayer (SLB) system. Minimal inhibitory concentration (MIC) values remained in a similar micromolar range for both of the conjugates while their cellular uptake rate was improved significantly compared to the drug candidates. A correlation was found between membrane affinity properties and results of in vitro biological investigations. Analysis of physical/structural properties of SLB in contact with bioactive components and visualization of the structural change by atomic-force microscopy (AFM) provided information on the type and route of molecular interaction of drug construction with lipid layers. The possible role of electrostatic interactions between lipid layer and drug candidates was tested in Langmuir-balance experiments using negatively charged lipid mixture (DPPC+DPPG). Especially the peptide conjugates presented increased membrane affinity due to cationic character of the peptide sequence selected for the conjugate formation. That is supposed to be one reason for the enhanced cellular uptake observed in vitro on MonoMac6 cell line. The conjugation of antitubercular agents to a peptidic carrier is a promising approach to enhance membrane affinity, cellular uptake rate and in vitro selectivity.

Prognostic significance of claudin expression changes in breast cancer with regional lymph node metastasis.

Adherent and tight junction molecules have been described to contribute to carcinogenesis and tumor progression. Additionally, the group of claudin-low tumors have recently been identified as a molecular subgroup of breast carcinoma. In our study, we examined the expression pattern of claudins, beta-catenin and E-cadherin in invasive ductal (IDCs) and lobular (ILCs) carcinomas and their corresponding lymph node metastases (LNMs). Tissue microarrays of 97 breast samples (60 invasive ductal carcinomas, 37 invasive lobular carcinomas) and their corresponding LNMs have been analyzed immunohistochemically for claudin-1, -2, -3, -4, -5, -7, beta-catenin and E-cadherin expression. The stained slides were digitalized with a slide scanner and the reactions were evaluated semiquantitatively. When compared to LNMs, in the IDC group beta-catenin and claudin-2, -3, -4 and -7 protein expression showed different pattern while claudin-1, -2, -3, -4 and -7 were differently expressed in the ILC group. Lymph node metastases developed a notable increase of claudin-5 expression in both groups. Decrease or loss of claudin-1 and expression of claudin-4 in lymph node metastases correlated with reduced disease-free survival in our patients. According to our observations, the expression of epithelial junctional molecules, especially claudins, is different in primary breast carcinomas compared to their lymph node metastases as demonstrated by immunohistochemistry. Loss of claudin junctional molecules might contribute to tumor progression, and certain claudin expression pattern might be of prognostic relevance.