Immunohistochemical expression of CD117/KIT, HER2, and Erβ in schistosomal and non-schistosomal urothelial carcinoma of Egyptian patients

Bladder carcinoma is an endemic problem in Egypt with schistosomiasis being an additional risk factor. Due to gender disparities, Erβ investigation and its role in modulating chemosensitivity are studied. CD117/KIT expression is also considered since the emergence of the targets of the tyrosine kinase inhibitor imatinib mesylate (Gleevec). HER2 is one of the established therapeutic targets in many cancers. We aimed to investigate CD117/KIT immunoexpression in schistosomal and non-schistosomal urothelial carcinoma of Egyptian patients and its relationship with HER2 and Erβ expressions, correlating it with pertinent variables that will help to provide better treatment options of possible combined targeted and hormonal therapy that might be effective against this aggressive malignancy. Sixty cases of bladder carcinoma were tested. Depending on the schistosomiasis association status of each case, two groups have been established with 30 cases each. CD117/KIT, HER2, and ERβ immunostaining were done and correlated with clinico- immuno-pathological parameters. CD117/KIT expression was seen in 71.7% of cases that correlated significantly with schistosomiasis (P = 0.01). In addition, a positive correlation was detected between schistosomiasis association and the percentage of immunostained cells and intensity score of CD117/KIT with P = 0.027, 0.01, respectively. 30% and 61.7% of cases were positively stained with HER2 and Erβ, respectively, with no significant relation with schistosomiasis. Due to the high expression, we found further clinical trials are needed to offer individualized targeted therapeutic options in urothelial tumors using anti-CD117/KIT, HER2, and ERβ other than limited traditional chemo- and nontargeted therapies.

Current Targets and Bioconjugation Strategies in Photodynamic Diagnosis and Therapy of Cancer

Photodynamic diagnosis (PDD) and therapy (PDT) are emerging, non/minimally invasive techniques for cancer diagnosis and treatment. Both techniques require a photosensitizer and light to visualize or destroy cancer cells. However, a limitation of conventional, non-targeted PDT is poor selectivity, causing side effects. The bioconjugation of a photosensitizer to a tumor-targeting molecule, such as an antibody or a ligand peptide, is a way to improve selectivity. The bioconjugation strategy can generate a tumor-targeting photosensitizer conjugate specific for cancer cells, or ideally, for multiple tumor compartments to improve selectivity and efficacy, such as cancer stem cells and tumor neovasculature within the tumor microenvironment. If successful, such targeted photosensitizer conjugates can also be used for specific visualization and detection of cancer cells and/or tumor angiogenesis (an early event in tumorigenesis) with the hope of an early diagnosis of cancer. The purpose of this review is to summarize some current promising target molecules, e.g., tissue factor (also known as CD142), and the currently used bioconjugation strategies in PDT and PDD, with a focus on newly developed protein photosensitizers. These are genetically engineered photosensitizers, with the possibility of generating a fusion protein photosensitizer by recombinant DNA technology for both PDT and PDD without the need of chemical conjugation. We believe that providing an overview of promising targets and bioconjugation strategies will aid in driving research in this field forward towards more effective, less toxic, and non- or minimally invasive treatment and diagnosis options for cancer patients.

Strategic design to create HER2-targeting proteins with target-binding peptides immobilized on a fibronectin type III domain scaffold

Tumor-binding peptides such as human epidermal growth factor receptor 2 (HER2)-binding peptides are attractive therapeutic and diagnostic options for cancer. However, the HER2-binding peptides (HBPs) developed thus far are susceptible to proteolysis and lose their affinity to HER2 in vivo. In this report, a method to create a HER2-binding fluctuation-regulated affinity protein (HBP-FLAP) consisting of a fibronectin type III domain (FN3) scaffold with a structurally immobilized HBP is presented. HBPs were selected by phage-library screening and grafted onto FN3 to create FN3-HBPs, and the HBP-FLAP with the highest affinity (HBP sequence: YCAHNM) was identified after affinity maturation of the grafted HBP. HBP-FLAP containing the YCAHNM peptide showed increased proteolysis-resistance, binding to HER2 with a dissociation constant (K_D) of 58 nM in ELISA and 287 nM in biolayer interferometry and specifically detects HER2-expressing cancer cells. In addition, HBP-FLAP clearly delineated HER2-expressing tumors with a half-life of 6 h after intravenous injection into tumor-bearing mice. FN3-based FLAP is an excellent platform for developing target-binding small proteins for clinical applications.

A HER2-binding protein, HBP-FLAP, developed by peptide immobilization specifically binds to HER2 and has improved resistance to proteases.

Autoantibody against new gene expressed in prostate protein is traceable in prostate cancer patients

Aim: We assessed an autoantibody against new gene expressed in prostate (NGEP) protein for prostate cancer (PCa) that may better diagnosis and prognosis approaches in the patients with PCa. Methods: Autoantibodies against NGEP were measured in sera of PCa patients by ELISA. Results: The autoantibody against NGEP is present in a significantly higher proportion in the sera of PCa patients as compared with healthy controls (p < 0.001). An inverse significant correlation was found between seropositive patients and Gleason score (p < 0.05) and serum prostate-specific antigen (recombinant NGEP; p < 0.05). Conclusion: The data showed that measurement of autoantibody against NGEP as a novel prostate-specific antigen in sera can be used as a potential biomarker to discriminate well-differentiated PCa patients from normal subjects.

Potential Diagnostic and Therapeutic Applications of Oligonucleotide Aptamers in Breast Cancer

Breast cancer is one of the most common causes of cancer related deaths in women. Currently, with the development of early detection, increased social awareness and kinds of treatment options, survival rate has improved in nearly every type of breast cancer patients. However, about one third patients still have increased chances of recurrence within five years and the five-year relative survival rate in patients with metastasis is less than 30%. Breast cancer contains multiple subtypes. Each subtype could cause distinct clinical outcomes and systemic interventions. Thereby, new targeted therapies are of particular importance to solve this major clinical problem. Aptamers, often termed “chemical antibodies”, are functionally similar to antibodies and have demonstrated their superiority of recognizing target with high selectivity, affinity and stability. With these intrinsic properties, aptamers have been widely studied in cancer biology and some are in clinical trials. In this review, we will firstly discuss about the global impacts and mechanisms of breast cancer, then briefly highlight applications of aptamers that have been developed for breast cancer and finally summarize various challenges in clinical translation of aptamers.

Evolution of anti-HER2 therapies for cancer treatment

The development of HER2-directed monoclonal antibodies and tyrosine kinase inhibitors have provided benefits to cancer patients, as well as produced many insights into the biology of the ErbB receptor family. Current therapies based on ErbB family members have resulted in improved overall survival with associated improvements in quality of life for the cancer patients that respond to treatment. Compared to monotherapy using either two antibodies to block the HER2 receptor blockade or combinatorial approaches with HER2 antibodies and standard therapies has provided additional benefits. Despite the therapeutic success of existing HER2 therapies, personalising treatment and overcoming resistance to these therapies remains a significant challenge. The heterogeneous intra-tumoural HER2 expression and lack of fully predictive and prognostic biomarkers remain significant barriers to improving the use of HER2 antibodies. Imaging modalities using radiolabelled pertuzumab and trastuzumab allow quantitative assessment of intra-tumoural HER2 expression, HER2 antibody saturation and the success of different drug delivery systems to be assessed. Molecular imaging with HER2 antibodies has the potential to be a non-invasive, predictive and prognostic technique capable of influencing therapeutic decisions, predicting response and failure of treatments as well as providing insights into receptor recycling and signalling. Similarly, conjugating HER2 antibodies with novel toxic payloads or combining HER2 antibodies with cellular immunotherapy provide exciting new opportunities for the management of tumours overexpressing HER2. Future research will lead to higher therapeutic responses, lower toxicities and providing insight into the mechanisms of resistance to HER2-targeted treatments.