Abstract. Leishmania are parasitic protozoa with two major stages in their life cycle: flagellated promastigotes that live in the gut of the insect vector and nonflagellated amastigotes that live inside the lysosomes of the vertebrate host macrophages. The Pro-1 glucose transporter of L. enriettii exists as two isoforms, iso-1 and iso-2, which are both expressed primarily in the promastigote stage of the life cycle. These two isoforms constitute modular structures: they differ exclusively and extensively in their NH~-terminal hydrophilic domains, but the remainder of each isoform sequence is identical to that of the other. We have localized these glucose transporters within promastigotes by two approaches. In the first method, we have raised a polyclonal antibody against the COOH-terminal hydrophilic domain shared by both iso-1 and iso-2, and we have used this antibody to detect the transporters by confocal immunofluorescence microscopy and immunoelectron microscopy. The staining observed with this antibody occurs primarily on the plasma membrane and the membrane of the flagellar pocket, but there is also light staining on the flagellum. We have also localized each isoform separately by introducing an epitope tag into each protein sequence, These experiments demonstrate that iso-1, the minor isoform, resides primarily on the flagellar membrane, while iso-2, the major isoform, is located on the plasma membrane and the flagellar pocket. Hence, each isoform is differentially sorted, and the structural information for targeting each transporter isoform to its correct membrane address resides within the NH2-terminal hydrophilic domain.F IACILITATED glucose transporters are integral membrane proteins (31), present in a diverse spectrum of organisms from bacteria to humans, that shuttle glucose across the plasma membrane and allow uptake and subsequent metabolism of this vital nutrient. Many organisms possess multiple glucose transporter isoforms with distinct biochemical properties (35), and some of these isoforms are localized to different subcellular compartments. Thus, mammalian GLUT1 is targeted primarily to the plasma membrane in fat and muscle cells, whereas GLUT4 is directed primarily to intracellular vesicles (32) that fuse with the plasma membrane after insulin stimulation of the target cell. A problem of considerable interest has been to determine how such isoforms are differentially targeted to their respective subcellular locations. Previous studies on the parasitic protozoan Leishmania enriettii have revealed that this microorganism expresses two closely related isoforms (34) of a major glucose transporter designated Pro-1. Both isoforms of the Pro-1 transporter are expressed in the promastigote or insect stage of the parasite life cycle, but their mRNAs accumulate to only a residual level in the amastigote form of the parasite that lives within the macrophage lysosomes of the vertebrate host (4). These two isoforms (iso-1 and iso-2) possess distinct NH2-terminal hydrophilic domains, predicted to be orien...

Periostin (POSTN) expression in cancer cells and circulation has been related to poor prognosis of colorectal carcinoma (CRC). However, the role of POSTN expressed in intra-tumoral stroma on CRC progression remains largely unknown. This study enrolled 1098 CRC patients who received surgical treatment in Shanghai and Guangzhou, Mainland China. In Shanghai cohort, immunohistochemistry score of stromal POSTN expression increased consecutively from adjacent mucosa, primary CRC tissues, to metastatic CRC tissues (P < 0.001), while medium- and high-stromal POSTN expression, rather than epithelial POSTN expression, independently predicted unfavorable prognoses of CRC, adjusted for covariates including TNM stage and postoperative chemotherapy in multivariate Cox models. The results in Shanghai cohort were faithfully replicated in Guangzhou cohort. Stromal POSTN expression dose-dependently predicted an unfavorable prognosis of stage III CRC patients with postoperative chemotherapy in both cohorts. POSTN derived from colonic fibroblasts or recombinant POSTN significantly promoted proliferation, anchorage independent growth, invasion, and chemo-resistance of CRC cells; whereas these effects were counteracted via targeting to PI3K/Akt or Wnt/β-catenin signaling pathway. CRC cell RKO-derived factor(s) significantly induced POSTN production in colonic fibroblasts and autocrine POSTN promoted proliferation, migration, and anchorage independent growth of fibroblasts. Conclusively, stromal POSTN is prognostic and predictive for CRC via creating a niche to facilitate cancer progression. Targeting POSTN-induced signaling pathways may be therapeutic options for metastatic or chemoresistant CRC.

The polarization of tumor‐associated macrophages (TAMs) and tumor‐associated neutrophils (TANs), especially from the antitumoral phenotype to the protumoral phenotype under certain conditions, has an important influence on the progression of tumors. However, the interactions and combined prognosis of these cells are poorly known. Here, we detected the infiltration of CD68+ TAMs, CD163+ TAMs, and CD66b+ TANs in the specimens from 662 patients with GC by immunohistochemistry. The results showed that the infiltration of each of CD163+, CD68+, and CD66b+ cells in GC tissue was significantly increased and independently associated with GC prognosis. Strong collinearity (r = 0.690, P < 0.001) was found between the infiltration of CD163+ and CD68+ cells in GC, and multivariate Cox analysis confirmed the infiltration of CD163+ cells was a better predictor for prognosis than that of CD68+ cells. The combination of the infiltration of CD163+ and CD66b+ cells provided more accurate survival prediction than any individual marker. Patient subgroups with CD66blowCD163low (hazard ratio (HR) = 2.161; 95% confidence interval (CI)  = 1.266–3.688; P < 0.001), CD66bhighCD163high (HR = 3.575; 95% CI = 2.155–5.933; P < 0.001), and CD66blowCD163high (HR = 7.514; 95% CI = 4.583–12.312; P < 0.001) were gradually associated with shorter DFS when compared with the subgroup with CD66bhighCD163low. The similar result was also for DSS among the subgroups. Moreover, the two‐marker model could more effectively discriminate the prognosis among the patients with chemotherapy than that among those without chemotherapy. We concluded that CD163+ TAMs were a more valuable prognostic marker than CD68+ TAMs, and CD163+ TAMs combined with CD66b+ TANs could more precisely predict the prognosis of patients with GC.

Resveratrate exerts protective effects against repetitive ssUVR-induced sunburn and suntan.