Epigenomic Silencing of Multiple Critical Genes in Breast Cancer with CRISPRoff and Genetically-Modified HIV-۱/Herolizin Vector

Cancer is one of the oldest diseases ever described by medicine. Breast cancer among women in the vast majority of countries worldwide, representing a quarter of all cancers diagnosed in women. The broad field of gene therapy promises a number of innovative treatments that are likely to become important in preventing deaths from cancer. immunotherapy, oncolytic virotherapy and gene transfer are methods which used for Cancer Treatment. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) systems and their CRISPR associated proteins (Cas proteins) have allowed for an unprecedented ability to manipulate the genome. An important strategy to battle excessive activity of CRISPR complexes would be to develop CRISPR-OFF switches. this supramolecular strategy can be used to switch off CRISPR/Cas۹-mediated genome editing in human cells. For Multiple gene Editing, researchers developed a DAP strategy in human cells, via an engineered ۷۵-nt hCtRNA, to express the hCtRNA-gRNA multiplex array and direct the release of individual gRNAs. Here, we intend to target multiple critical and overexpressed Genes in Breast Cancer cell's (BCs) and Breast Cancer stem cells (BCSCs). This is done by transferring designed reversed multiplex hCtRNA-gRNA and Gene silencing CRISPRoff Sequences with genetically modified HIV-۱ Vector. This gene transfer induces CRISPRoff expression within tumor cells, blocking Multiple genes from transcription. As example, targeting hTERT gene in cancer cells, which used the enzyme telomerase to maintain telomere length, stops after several cell divisions. Results revealed that epithelial-to-mesenchymal transition pathway could be potential pathways accounting for the progression in breast cancer, and CDK۱, CCNA۲, TOP۲A, CCNB۱, KIF۱۱, and MELK may be potential crucial genes. We also design new surface protein, called "Herolizin" which was include the fusion of heregulin-α۱ as targeting ligand (to target Breast cancer cells via HER۲/۳ or HER۲/۴ Receptors), Env-Sp and N-Glycans to target tumor cells with high precision and coverage on transfer vector surface. This ligand binds with high affinity to HER۲/۳ or HER۲/۴ heterodimers, which are overexpressed on certain aggressive breast cancers. In addition, this ligand is rapidly internalized after binding, thus adding to the utility of heregulin for targeting. Evp-Sp or Vpu-Env overlapping region (VEOR), assist in immune evasion by altering Env epitope exposure. Glycosylation variation can mediate antibody immune escape, including cases where the carbohydrate is direct component of the epitope. These Glycans facilitate immune evasion by masking the neutralizing antibody (NAb) epitopes and also form epitopes for broadly neutralizing PG۹/۱۶ and PGT (bNAbs).

کلیدواژه ها:

Breast Cancer ، CRISPRoff ، DAP ، hTERT ، Herolizin