Purpose: The goal of this study was to understand the role of altered mitochondrial function in breast cancer progression and determine the potential of the molecular alteration signature in developing exosome-based biomarkers.Experimental Design: This study was designed to characterize the critical components regulating mitochondrial function in breast tumorigenesis. Experiments were conducted to assess the potential of these molecules for exosome-based biomarker development.Results: We observed a remarkable reduction in spontaneous metastases through the interplay in mitochondria by SH3GL2, vesicular endocytosis-associated protein and MFN2, an important regulator of mitochondrial fusion. Following its overexpression in breast cancer cells, SH3GL2 translocated to mitochondria and induced the production of superoxide and release of cytochrome C from mitochondria to the cytoplasm. These molecular changes were accompanied by decreased lung and liver metastases and primary tumor growth. SH3GL2 depletion reversed the above phenotypic and associated molecular changes in nontumorigenic and tumorigenic breast epithelial cells. Loss of SH3GL2 and MFN2 expression was evident in primary human breast cancer tissues and their positive lymph nodes, which was associated with disease progression. SH3GL2 and MFN2 expression was detected in sera exosomes of normal healthy women, but barely detectable in the majority of the women with breast cancer exhibiting SH3GL2 and MFN2 loss in their primary tumors.Conclusions: This study identified a new mitochondria reprogramming pathway influencing breast cancer progression through SH3GL2 and MFN2. These proteins were frequently lost in breast cancer, which was traceable in the circulating exosomes. Clin Cancer Res; 22(13); 3348-60. Ó2016 AACR.

No abstract

No abstract

BackgroundOsteopontin (Eta, secreted sialoprotein 1, opn) is secreted from different cell types including cancer cells. Three splice variant forms namely osteopontin-a, osteopontin-b and osteopontin-c have been identified. The main astonishing feature is that osteopontin-c is found to be elevated in almost all types of cancer cells. This was the vital point to consider it for sequence analysis and structure predictions which provide ample chances for prognostic, therapeutic and preventive cancer research.MethodsOsteopontin-c gene sequence was determined from Breast Cancer sample and was translated to protein sequence. It was then analyzed using various software and web tools for binding pockets, docking and druggability analysis. Due to the lack of homological templates, tertiary structure was predicted using ab-initio method server – I-TASSER and was evaluated after refinement using web tools. Refined structure was compared with known bone sialoprotein electron microscopic structure and docked with CD44 for binding analysis and binding pockets were identified for drug designing.ResultsSignal sequence of about sixteen amino acid residues was identified using signal sequence prediction servers. Due to the absence of known structures of similar proteins, three dimensional structure of osteopontin-c was predicted using I-TASSER server. The predicted structure was refined with the help of SUMMA server and was validated using SAVES server. Molecular dynamic analysis was carried out using GROMACS software. The final model was built and was used for docking with CD44. Druggable pockets were identified using pocket energies.ConclusionsThe tertiary structure of osteopontin-c was predicted successfully using the ab-initio method and the predictions showed that osteopontin-c is of fibrous nature comparable to firbronectin. Docking studies showed the significant similarities of QSAET motif in the interaction of CD44 and osteopontins between the normal and splice variant forms of osteopontins and binding pockets analyses revealed several pockets which paved the way to the identification of a druggable pocket.

Triple negative breast cancer (TNBC) has poor survival, exhibits rapid metastases, lacks targeted therapies and reliable prognostic markers. Here, we examined metastasis promoting role of cancer testis antigen SPANXB1 in TNBC and its utility as a therapeutic target and prognostic biomarker. Expression pattern of SPANXB1 was determined using matched primary cancer, lymph node metastatic tissues and circulating small extracellular vesicles (sEVs). cDNA microarray analysis of TNBC cells stably integrated with a metastasis suppressor SH3GL2 identified SPANXB1 as a potential target gene. TNBC cells overexpressing SH3GL2 exhibited decreased levels of both SPANXB1 mRNA and protein. Silencing of SPANXB1 reduced migration, invasion and reactive oxygen species production of TNBC cells. S PANXB1 depletion augmented SH3GL2 expression and decreased RAC-1, FAK, A-Actinin and Vinculin expression. Phenotypic and molecular changes were reversed upon SPANXB1 re-expression. SPANXB1 overexpressing breast cancer cells with an enhanced SPANXB1:SH3GL2 ratio achieved pulmonary metastasis within 5 weeks, whereas controls cells failed to do so. Altered expression of SPANXB1 was detected in the sEVs of SPANXB1 transduced cells. Exclusive expression of SPANXB1 was traceable in circulating sEVs, which was associated with TNBC progression. SPANXB1 represents a novel and ideal therapeutic target for blocking TNBC metastases due to its unique expression pattern and may function as an EV based prognostic marker to improve TNBC survival. Uniquely restricted expression of SPANXB1 in TNBCs, makes it an ideal candidate for targeted therapeutics and prognostication.

No abstract

No abstract

Aim To establish the reliability, efficacy, and safety of disposable prism tonometry and validate its routine use for screening as well as monitoring of glaucoma. Methodology Intraocular pressure (IOP) of 400 eyes of 200 consecutive patients who attended the general ophthalmic clinic was checked with both the Goldmann applanation tonometer and a disposable tonometer prism by an experienced examiner after obtaining informed consent. The data were statistically analysed. Results The mean difference in the IOP between the two types of prisms was 0.1 mmHg (SD71 mmHg). Conclusion Disposable prism tonometry provides a reliable, effective, and safe alternative to Goldmann reusable prism tonometry for routine screening as well as monitoring of glaucoma with the advantages of eliminating the need for chemical disinfection and therefore eliminating the risk of crossinfection.