CAR T Cell Locomotion in Solid Tumor Microenvironment.

The promising outcomes of chimeric antigen receptor (CAR) T cell therapy in hematologic malignancies potentiates its capability in the fight against many cancers. Nevertheless, this immunotherapy modality needs significant improvements for the treatment of solid tumors. Researchers have incrementally identified limitations and constantly pursued better CAR designs. However, even if CAR T cells are armed with optimal killer functions, they must overcome and survive suppressive barriers imposed by the tumor microenvironment (TME). In this review, we will discuss in detail the important role of TME in CAR T cell trafficking and how the intrinsic barriers contribute to an immunosuppressive phenotype and cancer progression. It is of critical importance that preclinical models can closely recapitulate the in vivo TME to better predict CAR T activity. Animal models have contributed immensely to our understanding of human diseases, but the intensive care for the animals and unreliable representation of human biology suggest in vivo models cannot be the sole approach to CAR T cell therapy. On the other hand, in vitro models for CAR T cytotoxic assessment offer valuable insights to mechanistic studies at the single cell level, but they often lack in vivo complexities, inter-individual heterogeneity, or physiologically relevant spatial dimension. Understanding the advantages and limitations of preclinical models and their applications would enable more reliable prediction of better clinical outcomes.

Cell-Based Drug Discovery: Identification and Optimization of Small Molecules that Reduce c-MYC Protein Levels in Cells.

Elevated expression of the c-MYC oncogene is one of the most common abnormalities in human cancers. Unfortunately, efforts to identify pharmacological inhibitors that directly target MYC have not yet yielded a drug-like molecule due to the lack of any known small molecule binding pocket in the protein, which could be exploited to disrupt MYC function. We have recently described a strategy to target MYC indirectly, where a screening effort designed to identify compounds that can rapidly decrease endogenous c-MYC protein levels in a MYC-amplified cell line led to the discovery of a compound series that phenocopies c-MYC knockdown by siRNA. Herein, we describe our medicinal chemistry program that led to the discovery of potent, orally bioavailable c-MYC-reducing compounds. The development of a minimum pharmacophore model based on empirical structure activity relationship as well as the property-based approach used to modulate pharmacokinetics properties will be highlighted.

Renal and perinephric abscesses involving Lactobacillus jensenii and Prevotella bivia in a young woman following ureteral stent procedure.

 is a gram-positive bacillus in the female genital tract believed to be a commensal organism that inhibits the growth of more virulent pathogens. Prevotella bivia is a gram-negative bacillus species also typically commensal in the female genital tract. Lactobacillus as the primary causative agent in perinephric abscesses and bacteremia has been documented, albeit very uncommon and opportunistic. Prevotella bivia is not classically associated with perinephric abscesses but has been implicated in rare cases of pelvic inflammatory disease and tubo-ovarian abscesses. In this report, we present a 26-year-old immunocompetent woman with a recent history of nephrolithiasis treated with lithotripsy, ureteral stent placement and removal, and antibiotics who was admitted for fever and severe right flank pain. Imaging showed a right-sided renal and perinephric abscesses colonized by Lactobacillus jensenii and Prevotella bivia. Blood cultures were also positive for Lactobacillus species. Per literature review, intravenous ceftriaxone and metronidazole were administered with successful resolution of abscesses and negative repeat blood cultures. To our knowledge, this is the first case of simultaneous renal system abscesses caused by Lactobacillus and Prevotella species. Nephrolithiasis and prior antibiotics likely contributed to the opportunistic pathogenesis in this otherwise immunocompetent patient.

DIAGNOSIS AND TREATMENT OF A UNILATERAL RENAL CYSTADENOMA IN AN AFRICAN LION (PANTHERA LEO).

A renal tubular cystadenoma was diagnosed in a 14-yr-old male African lion (Panthera leo). During a routine health evaluation, a left renal mass was identified via physical examination, radiographs, and abdominal ultrasonography. The mass was 30 × 15 cm in size and had a thin capsule with central hypoechoic fluid, suggestive of a perirenal cyst. An exploratory celiotomy with partial nephrectomy was performed without complications. Histologically, the tumor was characterized by a thick fibrous capsule surrounding multiple, variable-sized cysts that markedly compressed the adjacent fibrotic and atrophied renal cortex. Immunohistochemical labeling for Aquaporin-1 and Tamm-Horsfall protein was consistent with a renal tubular cystadenoma of proximal tubule origin. Renal cystadenomas are an uncommon benign epithelial neoplasm. There are only two documented case reports in domestic cats. This report represents the first documentation, to the authors' knowledge, of a renal cystadenoma in a lion.

Primary splenic torsion in dogs: 102 cases (1992-2014).

OBJECTIVE: To determine the percentage of dogs surviving to hospital discharge and identify factors associated with death prior to hospital discharge among dogs undergoing surgery because of primary splenic torsion (PST). DESIGN: Retrospective case series. ANIMALS: 102 client-owned dogs. PROCEDURES: Medical records of dogs with a confirmed diagnosis of PST that underwent surgery between August 1992 and May 2014 were reviewed. History, signalment, results of physical examination and preoperative bloodwork, method of splenectomy, concurrent surgical procedures, perioperative complications, duration of hospital stay, splenic histopathologic findings, and details of follow-up were recorded. Best-fit multivariate logistic regression was performed to identify perioperative factors associated with survival to hospital discharge. RESULTS: 93 of the 102 (91.2%) dogs survived to hospital discharge. German Shepherd Dogs (24/102 [23.5%]), Great Danes (15/102 [14.7%]), and English Bulldogs (12/102 [11.8%]) accounted for 50% of cases. Risk factors significantly associated with death prior to hospital discharge included septic peritonitis at initial examination (OR, 32.4; 95% confidence interval [CI], 2.1 to 502.0), intraoperative hemorrhage (OR, 22.6; 95% CI, 1.8 to 289.8), and postoperative development of respiratory distress (OR, 35.7; 95% CI, 2.7 to 466.0). Histopathologic evidence of splenic neoplasia was not found in any case. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that the prognosis for dogs undergoing splenectomy because of PST was favorable. Several risk factors for death prior to discharge were identified, including preexisting septic peritonitis, intraoperative hemorrhage, and postoperative development of respiratory distress.

Factors associated with pathological fractures in dogs with appendicular primary bone neoplasia: 84 cases (2007-2013).

OBJECTIVE: To determine the incidence of pathological fractures associated with appendicular primary bone tumors in dogs managed medically and to identify potential risk factors at the time of radiographic diagnosis that may be associated with eventual pathological fracture. DESIGN: Retrospective case series. ANIMALS: 84 dogs with primary long bone neoplasia treated medically. PROCEDURES: Medical records for dogs with a diagnosis of primary long bone neoplasia based on results of radiography that was confirmed subsequently at necropsy were reviewed. Owners elected medical treatment at a pain clinic. Data regarding clinical signs, diagnostic testing, pathological findings, and outcome were evaluated. RESULTS: 84 dogs met study inclusion criteria with 85 limbs affected. Osteosarcoma was the most common tumor and was identified in 78 of 85 (91.8%) limbs. The median time from diagnosis to euthanasia was 111 days (range, 28 to 447 days). Pathological fractures were identified in 33 of 85 limbs (38%), with the femur most commonly affected, (8/14 [57.1%]), followed by the tibia (9/17 [52.9%]), humerus (10/27 [37%]), radius (5/25 [20%]), and ulna (1/2 [50%]). Logistic regression analysis indicated that tumors arising from long bones other than the radius had odds of eventual fracture 5.05 as great as the odds for tumors of the radius, and lytic tumors had odds of eventual fracture 3.22 as great as the odds for tumors that appeared blastic or mixed lytic-blastic. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that radial primary bone tumors were less likely and lytic tumors were more likely to fracture. The overall incidence of pathological fractures secondary to appendicular primary bone neoplasia in this study with patients treated by means of intensive management for bone pain was higher than previously reported.

Single-incision, laparoscopic-assisted jejunal resection and anastomosis following a gunshot wound.

A 2 yr old castrated male Pomeranian was evaluated for a 6 wk history of chronic vomiting, intermittent anorexia, and lethargy. Physical examination revealed a palpable, nonpainful, soft-tissue mass in the midabdominal area. Abdominal radiographs and ultrasound revealed a focal, eccentric thickening of the jejunal wall with associated jejunal mural foreign body and partial mechanical obstruction. Following diagnosis of a partial intestinal obstruction as the cause of chronic vomiting, the patient underwent general anesthesia for a laparoscopic-assisted, midjejunal resection and anastomosis using a single-incision laparoscopic surgery port. The patient was discharged the day after surgery, and clinical signs abated according to information obtained during a telephone interview conducted 2 and 8 wk postoperatively. The dog described in this report is a unique case of partial intestinal obstruction treated by laparoscopic-assisted resection and anastomosis using a single-incision laparoscopic surgery port.

EGG-3 regulates cell-surface and cortex rearrangements during egg activation in Caenorhabditis elegans.

Fertilization triggers egg activation and converts the egg into a developing embryo. The events of this egg-to-embryo transition typically include the resumption of meiosis, the reorganization of the cortical actin cytoskeleton, and the remodeling of the oocyte surface. The factors that regulate sperm-dependent egg-activation events are not well understood. Caenorhabditis elegans EGG-3, a member of the protein tyrosine phosphatase-like (PTPL) family, is essential for regulating cell-surface and cortex rearrangements during egg activation in response to sperm entry. Although fertilization occurred normally in egg-3 mutants, the polarized dispersal of F-actin is altered, a chitin eggshell is not formed, and no polar bodies are produced. EGG-3 is associated with the oocyte plasma membrane in a pattern that is similar to CHS-1 and MBK-2. CHS-1 is required for eggshell deposition, whereas MBK-2 is required for the degradation of maternal proteins during the egg-to-embryo transition. The localization of CHS-1 and EGG-3 are interdependent and both genes were required for the proper localization of MBK-2 in oocytes. Therefore, EGG-3 plays a central role in egg activation by influencing polarized F-actin dynamics and the localization or activity of molecules that are directly involved in executing the egg-to-embryo transition.

The egg surface LDL receptor repeat-containing proteins EGG-1 and EGG-2 are required for fertilization in Caenorhabditis elegans.

The molecular machinery that mediates sperm-egg interactions at fertilization is largely unknown. We identify two partially redundant egg surface LDL receptor repeat-containing proteins (EGG-1 and EGG-2) that are required for Caenorhabditis elegans fertility in hermaphrodites, but not males. Wild-type sperm cannot enter the morphologically normal oocytes produced by hermaphrodites that lack egg-1 and egg-2 function despite direct gamete contact. Furthermore, we find that levels of meiotic maturation/ovulation and sperm migratory behavior are altered in egg-1 mutants. These observations suggest an unexpected regulatory link between fertilization and other events necessary for reproductive success. egg-1 and egg-2 are the result of a gene duplication in the nematode lineage leading to C. elegans. The two closely related species C. briggsae and C. remanei encode only a single egg-1/egg-2 homolog that is required for hermaphrodite/female fertility. In addition to being the first identified egg components of the nematode fertilization machinery, the egg-1 and egg-2 gene duplication could be vital with regards to maximizing C. elegans fecundity and understanding the evolutionary differentiation of molecular function and speciation.