Methionine gamma lyase fused with S3 domain VGF forms octamers and adheres to tumor cells via binding to EGFR.

Methods for targeting enzymes exhibiting anticancer properties, such as methionine γ-lyase (MGL), have not yet been sufficiently developed. Here, we present the data describing the physico-chemical properties and cytotoxic effect of fusion protein MGL-S3 - MGL from Clostridium sporogenes translationally fused to S3 domain of the viral growth factor of smallpox. MGL-S3 has methioninase activity comparable to native MGL. In solution, MGL-S3 protein primarily forms octamers, whereas native MGL, on the contrary, usually forms tetramers. MGL-S3 binds to the surface of the neuroblastoma SH-SY5Y and epidermoid carcinoma A431 cells and, unlike native MGL, remains there and retains its cytotoxic effect after media removal. In HEK293T cells lacking EGFRs, no adhesion was recorded. Confocal fluorescence microscopy confirms the preferential adhesion of MGL-S3 to tumor cells, while it avoids getting into lysosomes. Both MGL and MGL-S3 arrest cell cycle of SH-SY5Y cells mainly in the G1 phase, while only MGL-S3 retains this ability after washing the cells.

Optogenetic cytosol acidification of mammalian cells using an inward proton-pumping rhodopsin.

Ion gradients are a universal form of energy, information storage and conversion in living cells. Advances in optogenetics inspire the development of novel tools towards control of different cellular processes with light. Rhodopsins are perspective tools for optogenetic manipulation of ion gradients in cells and subcellular compartments, controlling pH of the cytosol and intracellular organelles. The key step of the development of new optogenetic tools is evaluation of their efficiency. Here, we used a high-throughput quantitative method for comparing efficiency of proton-pumping rhodopsins in Escherichia coli cells. This approach allowed us to show that an inward proton pump xenorhodopsin from Nanosalina sp. (NsXeR) is a powerful tool for optogenetic control of pH of mammalian subcellular compartments. Further, we demonstrate that NsXeR can be used for fast optogenetic acidification of the cytosol of mammalian cells. This is the first evidence of optogenetic cytosol acidification by an inward proton pump at physiological pH values. Our approach offers unique opportunities to study cellular metabolism at normal and pathological conditions and might help to understand the role of pH dysregulation in cellular dysfunctions.

[Endovideosurgery (minimally invasive surgery) in treatment for malignant tumors of female genital organs: a 5-year experience of the clinic of the N.N.Petrov Research Institute of Oncology].

During the period of 2010-2015 laparoscopic surgery was performed in 1263 patients: 1113 with endometrial cancer (588 hysterectomies, 509 hysterectomies with pelvic lymphadenectomy, among them 16 with sentinel lymph node (SLN) mapping with Indocyanine green (ICG)); 86 with cervical cancer (80 nerve-sparing radical hysterectomies (NSRH), among them 15 with SLN mapping, 6 radical vaginal trachelectomies with endovideoassisted lymphadenectomy); 64 with ovarian malignancies. The average operating time in the group of hysterectomies was 101 minutes, in the group of hysterectomies with pelvic lymphadenectomy - 184 minutes, in the group of NSRH - 230 minutes. Average blood loss was less than 50 ml. No intraoperative complications were registered. Asymptomatic lymph cysts were observed in 122 cases. Symptomatic lymph cysts requiring surgical treatment were registered in 9 cases. Inconsistencies of vaginal sutures after radical hysterectomy were in two cases, ureterovaginal fistulas - in two cases. During a 3-year follow-up period twelve recurrences were observed in endometrial cancer patients (12/443; 2,7%), four patients (0,9%) died from disease. After NSRH two local recurrences (2,5%) were registered in patients with cervical cancer, after radical trachelectomy -two local recurrences (33%). One patient became pregnant in the group of vaginal trachelectomies. Therefore laparoscopic approach in treatment of female genital malignacies allows performing an adequate volume of surgery with minimal risk of intra- and postoperative complications, favorable course of the rehabilitation period, and oncological safety.