Refined immunoRNases for the efficient targeting and selective killing of tumour cells: A novel strategy.

In order to overcome limitations of conventional cancer therapy methods, immunotoxins with the capability of target-specific action have been designed and evaluated pre-clinically, and some of them are in clinical studies. Targeting cancer cells via antibodies specific for tumour-associated surface proteins is a new biomedical approach that could provide the selectivity that is lacking in conventional cancer therapy methods such as radiotherapy and chemotherapy. A successful example of an approved immunotoxin is represented by immunoRNases. ImmunoRNases are fusion proteins in which the toxin has been replaced by a ribonuclease. Conjugation of RNase molecule to monoclonal antibody or antibody fragment was shown to enhance specific cell-killing by several orders of magnitude, both in vitro and in animal models. There are several RNases obtained from different mammalian cells that are expected to be less immunogenic and systemically toxic. In fact, RNases are pro-toxins which become toxic only upon their internalization in target cells mediated by the antibody moiety. The structure and large size of the antibody molecules assembled with the immunoRNases have always been a challenge in the application of immunoRNases as an antitoxin. To overcome this obstacle, we have offered a new strategy for the application of immunoRNases as a promising approach for upgrading immunoRNAses with maximum affinity and high stability in the cell, which can ultimately act as an effective large-scale cancer treatment. In this review, we introduce the optimized antibody-like molecules with small size, approximately 10 kD, which are presumed to significantly enhance RNase activity and be a suitable agent with the potential for anti-cancer functionality. In addition, we also discuss new molecular entities such as monobody, anticalin, nonobody and affilin as refined versions in the development of immunoRNases. These small molecules express their functionality with the suitable small size as well as with low immunogenicity in the cell, as a part of immunoRNases.

Analysis of partial AZFc (gr/gr, b1/b3, and b2/b3) deletions in Iranian oligozoospermia candidates for intracytoplasmic sperm injection (ICSI)

Background/aim: Infertility is a main health issue. The human Y chromosome contains essential genes for spermatogenesis, especially those located on four major intervals defined as AZFa, AZFb, AZFc, and AZFd. A partial deletion of the AZFc region is reported as a significant risk factor for oligo-/azoospermia. The main purpose of this study was to investigate the prevalence of partial deletions in the AZFc region (gr/gr, b1/b3, and b2/b3) in Iranian oligozoospermic candidates for intracytoplasmic sperm injection. Materials and methods: Multiplex PCR was used to assess the micro and partial deletions in 60 oligozoospermia infertile and 80 fertile men. Results: Two cases (3.33%) showed AZFb deletion but no microdeletion was detected in the control samples. In the AZFc region, 20% of the patients showed deletions, in which 15% and 5% showed gr/gr and b2/b3 deletions, respectively. However, 10% of the healthy individuals also showed partial deletions, including gr/gr (7.5%) and b2/b3 (2.5%). No significant correlation was detected between the presence of gr/gr microdeletion in patients and controls (P > 0.05). Conclusion: Our study showed that the partial AZFc deletions are not associated with male infertility in Iranian subjects.