Membrane-associated mucins of the ocular surface: New genes,new protein functions and new biological roles in human and mouse

The mucosal glycocalyx of the ocular surface constitutes the point of interaction between the tear film and the apical epithelial cells. Membrane-associated mucins (MAMs) are the defining molecules of the glycocalyx in all mucosal epithelia. Long recognized for their biophysical properties of hydration, lubrication, anti-adhesion and repulsion, MAMs maintain the wet ocular surface, lubricate the blink, stabilize the tear film and create a physical barrier to the outside world. However, it is increasingly appreciated that MAMs also function as cell surface receptors that transduce information from the outside to the inside of the cell. A number of excellent review articles have provided perspective on the field as it has progressed since 1987, when molecular cloning of the first MAM was reported. The current article provides an update for the ocular surface, placing it into the broad context of findings made in other organ systems, and including new genes, new protein functions and new biological roles. We discuss the epithelial tissue-equivalent with mucosal differentiation, the key model system making these advances possible. In addition, we make the first systematic comparison of MAMs in human and mouse, establishing the basis for using knockout mice for investigations with the complexity of an in vivo system. Lastly, we discuss findings from human genetics/genomics, which are providing clues to new MAM roles previously unimagined. Taken together, this information allows us to generate hypotheses for the next stage of investigation to expand our knowledge of MAM function in intracellular signaling and roles unique to the ocular surface.     

内镜活检胃癌组织中MUC3A,MUC13表达及与病理参数和预后的关系

目的:探讨内镜活检胃癌组织中黏蛋白3A(MUC3A)、黏蛋白13(MUC13)表达及与病理参数和预后的关系。方法:选取2013年1月至2014年12月南阳市中心医院肿瘤科收治的接受内镜活检的116例患者胃癌组织和癌旁正常组织进行分析,采用免疫组织化学法检测所有组织样本中MUC3A,MUC13表达,观察二者表达情况,并分析二者与临床病理参数及预后的关系。结果:胃癌患者组织MUC3A,MUC13阳性率分别为68.97%和66.38%,高于正常组织的32.76%和7.76%(P<0.05);胃癌组织中MUC3A,MUC13表达与年龄、性别、肿瘤大小无关(P>0.05),与组织分化、浸润深度、TNM分期、淋巴结转移有关(P<0.05);随访5年结果显示:胃癌组织中MUC3A阳性患者中位生存时间为(40.50±1.95)个月,低于阴性患者的(48.67±2.51)个月(P<0.05),MUC3A阳性患者预后5年生存率为32.50%,低于阴性患者的55.56%(P<0.05);MUC13阳性患者中位生存时间为(38.52±1.92)个月,低于阴性患者的(49.06±2.71)个月(P<0.05),MUC13阳性患者预后5年生存率为30.00%,低于阴性患者的61.11%(P<0.05);COX多因素回归分析显示:TNM分期,淋巴结转移,MUC3A,MUC13是影响胃癌预后的独立危险因素(P<0.05)。结论:MUC3A,MUC13在胃癌组织中呈高表达,且与临床病理参数及预后密切相关,二者均有望作为判定胃癌发生发展及预后评估的参考指标。     

The co-expression characteristics of LAG3 and PD-1 on the T cells of patients with breast cancer reveal a new therapeutic strategy

Many studies have shown a special interaction between LAG3 and PD-1 in T cell inhibition, while the co-expression and effect of LAG3 and PD-1 on T cells in breast cancer patients are still not very clear. Here, with strict exclusion criteria, 88 patients with breast cancer and 18 healthy controls were enrolled. The percentages of LAG3⁺PD-1⁺ T cells in their peripheral blood (PBL) and tumor infiltrating T cells (TIL) were analyzed by flow cytometry, which showed an increase in TILs but no difference in PBLs and presented differences in TILs in different molecular subtypes (P < 0.05). In triple-negative breast cancer (TNBC), the highest percentages were observed, while in ER+/PR+ breast cancer, the lowest percentages were observed; however, these percentages were not different in different clinical stages (P > 0.05). Immunohistochemical staining showed that the expression of their ligands, PD-L1, MHC class II molecular and FGL1, was inconsistent in different molecular subtypes and clinical stages. Analysis of the functions of T cells with different phenotypes showed that the proliferation and secretion capacity of LAG3⁺PD-1⁺ T cells was obviously exhausted, with more than a two-fold of decrease compared with the groups of single positive LAG3 or PD-1 (P < 0.05). Finally, in a mouse model of TNBC, the dual blockade of LAG3 and PD-1 was indicated to achieve a better anti-tumour effect than either one alone (P < 0.05), which may provide a new strategy for the immunoregulatory treatment of patients with TNBC in the future.     

Porocarcinoma with areas of mucinous differentiation suggesting multilineage differentiation

Porocarcinoma is an infrequent malignant adnexal carcinoma, with some histopathological variants described, such as the clear cell, the sarcomatoid or the pigmented porocarcinoma. We report an invasive porocarcinoma showing areas of tumor cells floating in prominent dermal mucin, simulating mucinous carcinoma, that we consider a new histopathological variant of porocarcinoma. We report a 74‐year‐old male with previous history of multiple basal cell carcinomas that presented a nodule on his left temple. Histopathologic study showed a large ulcerated multilobular tumor composed of thickened cords of cells emanating from a hyperplastic epidermis and showing a mixed infiltrative and pushing pattern in the dermis. Poroid differentiation was observed in most of the neoplasm, both in intraepidermal and dermal invasive component. Within the neoplasm a prominent area where these small nests with clear formation of ducts were floating in mucinous pools with few septa intermingled was observed, simulating a primary cutaneous mucinous carcinoma. Cytology, immunohistochemistry and the presence of both neoplastic areas as closely related and with multiple points of connectivity favors the consideration of a composite tumor in this peculiar case. Other differentials are discussed.     

Mechanisms and biomarkers of immune quiescence in kidney transplantation

This review discusses the current understanding of biomarkers of immune quiescence based on reviews of published literature in kidney transplant operational tolerance and mechanistic studies based on a better characterization of the stable, well-functioning renal allograft.     

Generation of TIM3 inhibitory single-domain antibodies to boost the antitumor activity of chimeric antigen receptor T cells

Targeting inhibitory immune checkpoint molecules has significantly altered cancer treatment regimens. T cell immunoglobulin and mucin domain 3 (TIM3) is one of the major inhibitory immune checkpoints expressed on T cells. Blocking the engagement of TIM3 and its inhibitory ligand galectin-9 may potentiate the effects of immunotherapy or overcome the adaptive resistance to the therapeutic blockade of programmed cell death protein 1, cytotoxic T-lymphocyte-associated protein 4, B- and T-lymphocyte attenuator and lymphocyte-activation gene 3, amongst others, as each of these immune checkpoints harbors unique properties that set it apart from the rest. Heavy chain variable fragment (VH)-derived single-domain antibodies (sdAbs) represent a class of expanding drug candidates. These sdAbs have unique advantages, including their minimal size in the antibody class, ease of expression, broad scope for modular structure design and re-engineering, and excellent tumor penetration. In the present study, two sdAbs, TIM3-R23 and TIM3-R53, were generated by immunizing rabbits with the recombinant extracellular domain of TIM3 and applying phage display technology. These sdAbs were easily expressed in mammalian cells. The purified sdAbs were able to bind to both recombinant and cell surface TIM3, and blocked it from binding to the ligand galectin-9. In vivo studies demonstrated that TIM3-R53 was able to potentiate the antitumor activity of chimeric antigen receptor T cells that targeted mesothelin. In conclusion, the results of the present study suggested that TIM3-R53 may be a novel and attractive immune checkpoint inhibitor against TIM3, which is worthy of further investigation.     

Expression of Tim-3 in gastric cancer tissue and its relationship with prognosis

As a negative regulatory molecule, T-cell immunoglobulin–and mucin domain-3 (Tim-3) plays a crucial role in the tumor immunological tolerance. In the present study, we aimed to determine the Tim-3 expression in gastric cancer tissue and its relationship with clinicopathological parameters and prognosis. The Tim-3 expression was assessed in 52 gastric cancer specimens and 15 gastritis tissues by flow cytometry, and gastritis tissues served as the control. As a result, we found that the Tim-3 expressions on CD4⁺T cells and CD8⁺T cells in gastric cancer tissue was significantly higher than those in gastritis tissue (P=0.022, P=0.047, respectively). The median expression level of Tim-3 on CD4⁺T cells were significantly correlated with clinicopathological parameters, such as tumor size, lymph node metastasis, the depth of tumor invasion and TNM staging (P=0.042, P=0.026, P=0.001, P=0.003, respectively), while it was not correlated with sex, age and histological subtype (all P>0.05). In CD8⁺T cells, the Tim-3 expression was relevant to tumor invasion and TNM staging (P=0.035, P=0.017, respectively), while it was irrelevant to other clinicopathological parameters (all P>0.05). Additionally, Kaplan-Meier survival curves showed that the median overall survival time of patients with lower Tim-3 expression was greater than that of patients with higher Tim-3 expression in CD4⁺T cells and CD8⁺T cells (χ²=18.036, P<0.001 and χ²=18.036, P<0.001, respectively). Moreover, the multivariate analysis revealed that the Tim-3 expression and TNM stage were independent prognostic factors for gastric cancer patients (P=0.029, P=0.043 and P=0.003, respectively). These results suggest that Tim-3 played an important role in the development and progression of gastric cancer, and it could be used as an independent prognostic factor for gastric cancer patients.