The Tumor Immune Microenvironment in Clear Cell Renal Cell Carcinoma

Clear cell renal cell carcinoma (ccRCC) is a type of kidney cancer that arises from the cells lining the tubes of the kidney. The tumor immune microenvironment (TIME) of ccRCC is a complex interplay of various immune cells, cytokines, and signaling pathways. One of the critical features of the ccRCC TIME is the presence of infiltrating immune cells, including T cells, B cells, natural killer cells, dendritic cells, and myeloid-derived suppressor cells. Among these cells, CD8+ T cells are particularly important in controlling tumor growth by recognizing and killing cancer cells. However, the TIME of ccRCC is also characterized by an immunosuppressive environment that hinders the function of immune cells. Several mechanisms contribute to the immunosuppressive nature of the ccRCC TIME. For instance, ccRCC cells produce cytokines such as interleukin-10 (IL-10) and transforming growth factor-beta (TGF-β), which suppress immune cell activation and promote the differentiation of regulatory T cells (Tregs). Tregs, in turn, dampen the activity of effector T cells and promote tumor growth. In addition, ccRCC cells can express programmed death-ligand 1 (PD-L1), which interacts with the programmed cell death protein 1 (PD-1) receptor on T cells to inhibit their function. In addition, other immune checkpoint proteins, such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and lymphocyte activation gene 3 (LAG-3), also contribute to the immunosuppressive milieu of the ccRCC TIME. Finally, the hypoxic and nutrient-poor microenvironment of ccRCC can stimulate the production of immunosuppressive metabolites, such as adenosine and kynurenine, which further impair the function of immune cells. Understanding the complex interplay between tumor cells and the immune system in the ccRCC TIME is crucial for developing effective immunotherapies to treat this disease.

Increased levels of the 14-3-3 η and γ proteins in the synovial fluid of dogs with unilateral cranial cruciate ligament rupture

The present study investigated whether the 14-3-3 η and γ proteins, which are potent matrix metalloprotease (MMP) stimulators, are detectable in the synovial fluid of dogs with cranial cruciate ligament rupture (CCLR). Synovial fluid samples from 7 dogs with unilateral CCLR and control samples from 4 dogs without a history of any joint inflammation or any other abnormalities underwent Western blot analysis for the 14-3-3 η, γ, and σ proteins as well as MMP-1 and MMP-3. Craniocaudal and lateral radiographic projections of the stifle joint were evaluated for the presence and severity of 13 specific radiographic markers of osteoarthritis and graded numerically. The Spearman method was used to detect any correlation between the 14-3-3-η level in the synovial fluid and the radiograph-based grade. The η isoform was present only in the samples from the dogs with CCLR. The levels of 14-3-3-γ, MMP-1, and MMP-3 were significantly higher in the samples from the dogs with CCLR than in the control samples (P < 0.05). However, there was no significant difference between the CCLR and control samples in the level of the σ isoform. The Spearman method showed a significant correlation between the 14-3-3-η level in the synovial fluid and the presence of either patellar osteophytes or lateral or medial (or both) condylar periarticular osteophytes (P < 0.05). The MMP stimulatory effect of the 14-3-3 η and γ isoforms may be the reason for the high levels of MMP-1 and MMP-3 observed. Thus, 14-3-3 proteins, especially the η isoform, may be important markers of osteoarthritis caused by CCLR.

Primary human keratinocytes externalize stratifin protein via exosomes

Although, stratifin (SFN) is externalized by keratinocytes and stimulates the expression of matrix metalloproteinase-1 (MMP-1) in fibroblasts, its mechanism of externalization is not known. Here, we hypothesize that keratinocytes have a capacity to release stratifin through externalization of exosomes. To test this hypothesis, exosomes were purified from human keratinocyte conditioned medium (KCM) and analyzed for the presence of SFN by Western blot analysis using lysosomal-associated membrane protein 2 (LAMP-2) and heat shock cognate 70 (hsc70) as exosomal markers. The results showed the presence of SFN in keratinocyte lysate, concentrated KCM and exosomes, but not in concentrated unconditioned medium. Transmission electron microscopic examination revealed the presence of unique "saucer-like" structures characteristic of exosomes whose diameters were <100 nm. Similar to the recombinant SFN, the exosomes associated proteins stimulated MMP-1 expression in fibroblasts. Depletion of the exosomes markedly reduced this MMP-1 stimulatory effect. To further statistically confirm these findings, fibroblasts were treated with three different exosome preparations and the finding showed more than 7.4-fold increase in the level of MMP-1 in the treated cells. Furthermore, we found that approximately 1% of the total proteins contained in exosomes correspond to SFN. In conclusion, this study is the first report showing that keratinocytes have the capacity to produce exosomes through which some intracellular proteins such as SFN, with MMP-1 stimulating activity for fibroblasts, is externalized into keratinocyte microenvironment.

Endoscopic abdominoplasty: an alternative approach

We describe a technique for endoscopic abdominoplasty in which we used 3 incisions, following the triangulation principles. To maintain the subcutaneous cavity, CO2 was insufflated at 8 mm Hg, and Esmarch bandages were placed at the submammary fold in a circumferential way to prevent subcutaneous emphysema. The aponeurosis plication was done with interrupted "8" figure sutures, with extracorporeal knots tied up in a double fisherman knot. The rest of the technique is similar to those previously described. Seven patients were treated, with an average age of 35.7 years (range, 25-60), and the mean length of surgery was of 197.11 minutes (range, 129-240). After surgery, 2 patients had mild pulmonary hypoventilation treated only with oxygen through a nasal mask for 24 hours. There were other complications such as seromas, inadequate implantation of the navel, and superficial periumbilical necrosis. According to the patients' opinion, the esthetic results have been satisfactory so far.