Mass treatment with praziquantel (PZQ) monotherapy is the mainstay for schistosome treatment. This drug shows imperfect cure rates in the field and parasites showing reduced response to PZQ can be selected in the laboratory, but the extent of resistance in Schistosoma mansoni populations is unknown. We examined the genetic basis of variation in PZQ response in a S. mansoni population (SmLE-PZQ-R) selected with PZQ in the laboratory: 35% of these worms survive high dose (73 µg/mL) PZQ treatment. We used genome wide association to map loci underlying PZQ response. The major chr. 3 peak shows recessive inheritance and contains a transient receptor potential (Sm.TRPMPZQ) channel (Smp_246790), activated by nanomoles of PZQ. Marker-assisted selection of parasites at a single Sm.TRPMPZQ SNP enriched populations of PZQ-R and PZQ-S parasites showing >377 fold difference in PZQ response. The PZQ-R parasites survived treatment in rodents better than PZQ-S. Resistant parasites show 2.25-fold lower expression of Sm.TRPMPZQ than sensitive parasites. Specific chemical blockers of Sm.TRPMPZQ enhanced PZQ resistance, while Sm.TRPMPZQ activators increased sensitivity. A single SNP in Sm.TRPMPZQ differentiated PZQ-ER and PZQ-ES lines, but mutagenesis showed this was not involved in PZQ-R, suggesting linked regulatory changes. We surveyed Sm.TRPMPZQ sequence variation in 259 individual parasites from the Newand Old World revealing one nonsense mutation, that results in a truncated protein with no PZQ binding site. Our results demonstrate that Sm.TRPMPZQ underlies variation in PZQ response in S. mansoni and provides an approach for monitoring emerging PZQ-resistance alleles in schistosome elimination programs..

The prevalence and significance of programmed death-1 ligand (PD-L1) expression in different types of tubo-ovarian carcinoma have not been well defined. We evaluated PD-L1 expression and CD8+ tumor-infiltrating lymphocyte (TIL) density in whole tissue sections of 189 cases of tubo-ovarian carcinoma, including high-grade serous carcinoma (HGSC, n=100), clear cell carcinoma (CCC, n=24), endometrioid carcinoma (EmC, n=40), and mucinous carcinomas (MC, n=25). Using the tumor proportion score (TPS) with a 1% cutoff, PD-L1 expression was present in 21% of HGSC, 16.7% of CCC, 2.5% of EmC, and 4% of MC. Using the combined positive score (CPS) with a cutoff of 1, PD-L1 expression was present in 48% of HGSC, 25% of CCC, 20% of EmC, and 24% of MC. HGSC demonstrated significantly higher CD8+ TIL density than CCC (P=0.013238), EmC (P=0.01341), or MC (P=0.004556). In HGSC, CD8+ TIL density was directly correlated with PD-L1 positivity using either TPS (P=0.0008) or CPS (P=0.00011). Survival analysis of patients with high stage (stage III to IV) HGSC revealed PD-L1 positivity by TPS to be associated with improved progression-free survival (adjusted hazard ratio: 0.4912 vs. 2.036, P=0.0378). Although not statistically significant, a similar trend was observed in overall survival (adjusted hazard ratio: 0.3387 vs. 2.953, P=0.0548). In contrast, with CPS, no significant difference was identified between PD-L1-positive and negative groups in either progression-free survival (P=0.5086) or overall survival (P=0.7823). Neoadjuvant chemotherapy was associated with higher PD-L1 expression by TPS (P=0.00407) but not CPS. No significant difference in PD-L1 expression was detected in tumors from patients with germline BRCA1/2 mutations compared with germline mutation-negative tumors by either TPS or CPS. In conclusion, the prevalence of PD-L1 expression is variable in different types of tubo-ovarian carcinoma and is highest in HGSC. In high-stage HGSC, PD-L1 positivity in tumor cells is associated with an increased immune response and improved survival.

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Our primate model data provide the first proof-of-concept that mucosal IgM can prevent mucosal HIV transmission and have implications for HIV prevention and vaccine development.

The diagnosis of endometrioid intraepithelial neoplasia (EIN) is challenging owing to limited sampling, hormonal status, and other confounding histologic variables. Markers such as PTEN or PAX2 can delineate EIN in some cases, but are not wholly reliable. Clearly, new markers of EIN are needed. We explored several potential markers of EIN based rationally on molecular pathways most frequently misregulated in endometrial cancer: the 3-phosphoinositide kinase (PI3K)/AKT, β-catenin, and mismatch repair pathways. We studied PTEN, PAX2, β-catenin, and MLH1, in conjunction with 2 new markers—FOXO1 and phosphorylated AKT (pAKT)—not previously investigated in EIN. Benign (n=14) and EIN (n=35) endometria were analyzed by immunohistochemistry. Staining patterns were interpreted, tabulated, and scored by “clonal distinctiveness” in neoplastic lesions; that is, pattern alterations relative to normal glands. In normal endometria, FOXO1 was cytoplasmic in proliferative phase, but nuclear in secretory phase, showing that PI3K/FOXO1 participates in endometrial cycling and that FOXO1 is a readout of PI3K status. pAKT expression was low across normal endometria. FOXO1 or pAKT expression was altered in the majority of EINs (27/35, 77%), with FOXO1 and pAKT being co-altered only in some (20/35, 57%). β-catenin or MLH1 also exhibited clonal distinctiveness in EINs, showing that these are also useful markers in some cases. This is the first study to demonstrate the potential of pAKT and FOXO1 as biomarkers in the histopathologic evaluation of EIN. However, variability in expression poses challenges in interpretation.