The CDK Inhibitor Dinaciclib Improves Cisplatin Response in Nonseminomatous Testicular Cancer: A Preclinical Study.

BACKGROUND: Most patients with testicular germ cell tumors (GCTs) are treated with cisplatin (CP)-based chemotherapy. However, some of them may develop CP resistance and therefore represent a clinical challenge. Cyclin-dependent kinase 5 (CDK5) is involved in chemotherapy resistance in different types of cancer. Here, we investigated the possible role of CDK5 and other CDKs targeted by dinaciclib in nonseminoma cell models (both CP-sensitive and CP-resistant), evaluating the potential of the CDK inhibitor dinaciclib as a single/combined agent for the treatment of advanced/metastatic testicular cancer (TC). METHODS: The effects of dinaciclib and CP on sensitive and resistant NT2/D1 and NCCIT cell viability and proliferation were evaluated using MTT assays and direct count methods. Flow cytometry cell-cycle analysis was performed. The protein expression was assessed via Western blotting. The in vivo experiments were conducted in zebrafish embryos xenografted with TC cells. RESULTS: Among all the CDKs analyzed, CDK5 protein expression was significantly higher in CP-resistant models. Dinaciclib reduced the cell viability and proliferation in each cell model, inducing changes in cell-cycle distribution. In drug combination experiments, dinaciclib enhances the CP effect both in vitro and in the zebrafish model. CONCLUSIONS: Dinaciclib, when combined with CP, could be useful for improving nonseminoma TC response to CP.

The effect of chemotherapy in sarcomatoid bladder cancer patients treated with radical cystectomy.

INTRODUCTION: Data about the role of chemotherapy in sarcomatoid bladder cancer (SBC) are limited. We addressed the effect of chemotherapy in non-metastatic SBC patients treated with radical cystectomy (RC). METHODS: Using the Surveillance, Epidemiology, and End Results database (2001-2018), we identified 331 patients with non-metastatic muscle-invasive or higher SBC (T2-4N0-3M0). Kaplan-Meier plots and Cox regression models tested cancer-specific mortality (CSM ). Sample size and power analyses tested for power limitations. RESULTS: Of 331 SBC patients, 129 (38.9%) were exposed to chemotherapy. The rate of organ-confined stage (T2N0M0) was 33% in both chemotherapy-exposed and chemotherapy-naive patients. In the overall cohort, median CSM-free survival was 84 months (interquartile range [IQR] 21-NA) vs. 26 months (IQR 17-84) in chemotherapy exposed vs. chemotherapy-naive patients, respectively. In multivariable Cox regression models, chemotherapy was associated with lower CSM, without reaching statistical significance (hazard ratio [HR ] 0.72, confidence interval [CI] 0.51-1.01, p=0.054). In subgroup analyses, chemotherapy exposure in organ-confined (n=110) vs. non-organ-confined (n=221) patients resulted in a HR of 0.51 (p=0.12) vs. 0.77 (p=0.17), respectively. Power analyses, based on two-sided α=0.05, revealed values of 52%, 14%, and 43% in the entire population, organ-confined, and nonorgan-confined subgroups, respectively. CONCLUSIONS: In non-metastatic SBC treated with RC, the association between chemotherapy and lower CSM is particularly strong in organ-confined stage. A substantially larger cohort would be required to confirm the statistical significance of the recorded protective effect of chemotherapy.

Effect of inguinal lymph node dissection in lymph node negative patients with squamous cell carcinoma of the penis.

INTRODUCTION: The survival benefit of inguinal lymph node dissection (ILND) vs no ILND in patients with squamous cell carcinoma of the penis (SCCP) and the absence of lymph node invasion is unclear. We addressed this uncertainty within the Surveillance, Epidemiology and End Results (SEER 2000-2018) database. MATERIAL AND METHODS: We identified lymph node negative SCCP patients who either underwent ILND (pN0) or clinical examination only (cN0). We tested for the effect of ILND vs no ILND on cancer-specific mortality (CSM) in Kaplan-Meier plots, univariable and multivariable Cox regression analyses, in a pT stage-specific fashion, before and after 1:3 propensity score matching (PSM). Sensitivity analyses were conducted according to historical and contemporary treatment periods as well as geographic regions. RESULTS: Of 2520 SCCP patients, 369 (15%) underwent ILND (pN0) vs 2151 (85%) did not (cN0). The pN0 vs cN0 distribution according to pT stages was as follows: 80 (7%) vs 1092 (93%) in pT1b, and 289 (21%) vs 1059 (79%) in pT2-3. At 36 months, CSM-free survival in pT2-3 stage was 89% in ILND vs 74% in no ILND patients (multivariable hazard ratio: 0.42, CI 0.30-0.60, p < 0.001). This result was confirmed in sensitivity analyses, and after 1:3 PSM. The same analyses could not be completed in pT1b stage due to insufficient number of observations and events. CONCLUSIONS: In pT2-3 stage SCCP, a significantly lower CSM was recorded in lymph node negative patients treated with ILND than in their clinical lymph node negative counterparts who did not undergo ILND.

Efficacy of chemotherapy on overall survival in metastatic sarcomatoid bladder cancer patients.

Introduction: The role of chemotherapy in metastatic sarcomatoid bladder cancer (mSBC) is unknown. The current work aimed to test the effect of chemotherapy on overall survival (OS) in mSBC patients. Material and methods: Using the Surveillance, Epidemiology and End Results database (2001-2018), we identified 110 mSBC patients of all T and N stages (TanyNanyM1). Kaplan-Meier plots and Cox regression models were used. Covariates consisted of type of surgical treatment (no treatment vs radical cystectomy vs other), and patient age. The endpoint of interest was OS. Results: In 110 mSBC patients, 46 (41.8%) were exposed to chemotherapy vs 64 (58.2%) who were chemotherapy naive. Chemotherapy exposed patients were younger (median age 66 vs 70, p = 0.005). Median OS was 8 months in chemotherapy exposed vs 2 months in chemotherapy naive patients. In univariable Cox regression models, chemotherapy exposure was associated with a hazard ratio (HR) of 0.58 (p = 0.007).In multivariable Cox regression models adjusted for case mix, chemotherapy exposure was associated with a HR of 0.60 (p = 0.016). Conclusions: To the best of our knowledge, this is the first report of chemotherapy effect on OS in mSBC patients. OS is extremely poor. Nonetheless, it is improved in a statistically significant and clinically meaningful fashion, when chemotherapy is administered.

Neutropenia and the development of the systemic inflammatory response syndrome.

OBJECTIVE: To determine outcome and natural course of systemic inflammatory response syndrome (SIRS) stages in adult febrile neutropenic patients. DESIGN AND SETTING: Retrospective cohort study in the medicine department and intensive care unit of a university hospital. PATIENT: Adults with cancer-related neutropenia and community-acquired fever. MEASUREMENTS AND RESULTS: Patients were classified on admission according to SIRS parameters, tumor type, and degree of neutropenia. Records of clinical and laboratory data during hospitalization were reviewed. Univariate and logistic regression analyses were performed. Seventy-nine events in 62 patients were analyzed. Overall mortality rate was 20.2% (16/79). Mortality increased as SIRS stage worsened on admission. No patients with stage 2 SIRS died (neutropenia and fever alone) but 11.1% of patients with SIRS 3, 43.4% with SIRS 4, 66.6% with sepsis induced hypotension, and 90% with septic shock. SIRS stage on admission was an independent predictor of death and was related directly to rate of progression to shock, i.e., none of the patients with SIRS 2, 2.7%(1/36) of those with SIRS 3, and 30.4% (7/23) of those admitted with SIRS 4. CONCLUSIONS: Mortality and progression to septic shock increased as more SIRS criteria were met on admission. SIRS stages could serve as a risk-assessing model in febrile neutropenic patients.

Discordant effects of anti-VLA-4 treatment before and after onset of relapsing experimental autoimmune encephalomyelitis.

Initial migration of encephalitogenic T cells to the central nervous system (CNS) in relapsing experimental autoimmune encephalomyelitis (R-EAE), an animal model of multiple sclerosis (MS), depends on the interaction of the alpha4 integrin (VLA-4) expressed on activated T cells with VCAM-1 expressed on activated cerebrovascular endothelial cells. Alternate homing mechanisms may be employed by infiltrating inflammatory cells after disease onset. We thus compared the ability of anti-VLA-4 to regulate proteolipid protein (PLP) 139-151-induced R-EAE when administered either before or after disease onset. Preclinical administration of anti-VLA-4 either to naive recipients of primed encephalitogenic T cells or to mice 1 week after peptide priming, i.e., before clinical disease onset, inhibited the onset and severity of clinical disease. In contrast, Ab treatment either at the peak of acute disease or during remission exacerbated disease relapses and increased the accumulation of CD4(+) T cells in the CNS. Most significantly, anti-VLA-4 treatment either before or during ongoing R-EAE enhanced Th1 responses to both the priming peptide and endogenous myelin epitopes released secondary to acute tissue damage. Collectively, these results suggest that treatment with anti-VLA-4 Ab has multiple effects on the immune system and may be problematic in treating established autoimmune diseases such as MS.

Competencies for population-based clinical managers. A survey of managed care medical directors.

BACKGROUND: The evolution of American health care into integrated systems of delivery and finance requires a specialized set of population-based skills for physicians. The field of preventive medicine represents one source of this expertise. Specific competencies for the emerging area of managerial medicine have not been well delineated. METHODS: Using concept documents from the Residency Review Committee for Preventive Medicine and the American Board of Preventive Medicine, a list of proposed competencies for managerial medicine was identified. Surveys were mailed to medical directors of all members of the American Association of Health Plans and to a random sample of diplomates of the American Board of Preventive Medicine. Respondents were asked to rate the importance of these competencies for a population-oriented clinician manager. RESULTS: Areas rated highly by medical directors included health services research (including outcome research), quality assurance and improvement, health risk assessment and reduction, programmatic skills, and clinical preventive skills. Responses from preventive medicine specialists were similar, but placed lower emphasis on these skills. CONCLUSION: Despite its limited response rate, this survey may be useful in the implementation of specialty training in managerial medicine. Residency training programs may choose to emphasize specific content area that reflect the priorities expressed by physicians actively involved in management.

Production of interleukin-6 and granulocyte-macrophage colony-stimulating factor by murine iris and ciliary body explants.

PURPOSE: To examine the ability of murine iris-ciliary body explants to produce cytokines with proinflammatory activities. METHODS: Supernatants derived from murine iris-ciliary body (I-CB) tissue explants cultured (four per well in 1 ml medium) in the presence of indomethacin were analyzed for the production of IL-1, IL-2, IL-3, IL-6, tumor necrosis factor-alpha/beta (TNF alpha/beta) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Analysis was performed by thymocyte costimulation, growth factor-dependent cell proliferation, TGF-beta-sensitive mink lung epithelial cell proliferation, and enzyme-linked immunosorbent assays (ELISA). RESULTS: Supernatants from I-CB explants cultured in vitro for 24 hours contained significant thymocyte costimulatory activity. This activity was fully neutralized by a combination of antisera to IL-1 and IL-6, and ELISA analysis confirmed that IL-6 was a significant component of the supernatant (402.7 pg/ml). TNF alpha/beta were also found in low concentrations (approximately 2.0 U/ml) by ELISA analysis, whereas IL-2 and IL-4 were not detectable. Significant amounts of GM-CSF (15.8 U/ml), but no IL-3, were detected. CONCLUSIONS: These results demonstrate that normal I-CB tissue contains cells capable of producing IL-6, GM-CSF, and IL-1. Because of the proinflammatory nature of IL-6 and IL-1, and the ability of GM-CSF, IL-1, and IL-6 to enhance functional capabilities of antigen presenting cells, regulation of the production of these cytokines may contribute significantly to the maintenance of the immunologic status of this regional site.

The presence of biologically significant concentrations of glucocorticoids but little or no cortisol binding globulin within aqueous humor: relevance to immune privilege in the anterior chamber of the eye.

PURPOSE: Immunosuppressive factors in aqueous humor (AH) contribute to the immune-privileged status of the anterior chamber of the eye. One such factor is transforming growth factor-beta (TGF-beta); other relevant inhibitors have not been fully identified. The authors examined AH to search for other putative inhibitors and to determine their effect on TGF-beta inhibitory activity. METHODS: Radioimmunoassays (RIA) were used to detect the presence of hydrocortisone, corticosterone, cortisol binding globulin (CBG), and alpha-melanocyte stimulating hormone (alpha-MSH) in AH. The ability of these factors to inhibit murine thymocyte proliferation stimulated by phytohemagglutinin-interleukin 1 (PHA/IL-1) and proliferation of a TGF-beta-sensitive cell line (CCL64) in vitro was examined. The ability of hydrocortisone to inhibit a one-way mixed lymphocyte reaction (MLR) and the ability of epidermal cells to present soluble tumor-associated antigens (TAA) for elicitation of immunity in mice in the concentration range present in AH was also examined. RESULTS: Hydrocortisone was detected in mouse, rat, and human AH (10.8 +/- 1.1 ng/ml, 9.3 +/- 2.1 ng/ml, and 18.0 +/- 1.0 ng/ml, respectively; mean +/- SEM), as was corticosterone (2.7 +/- 0.9 ng/ml, 2.2 +/- 0.3 ng/ml, and 0.7 +/- 0.1 ng/ml, respectively). Whereas normal plasma contains a binding protein for corticosteroids (i.e., CBG), the concentration in mouse, rat, and human AH was less than the level detectable by an RIA. Hydrocortisone inhibited PHA/IL-1-stimulated murine thymocyte proliferation and CCL64 cell proliferation in the concentration range present in AH. When hydrocortisone was combined with TGF-beta 2 (125 pg/ml), the degree of inhibition observed was greater than with either alone. Corticosterone inhibited thymocyte costimulation only slightly at concentrations present in AH but was inhibitory for CCL64 cells. alpha-MSH was also detected in AH. The concentration present had only slight inhibitory effects for CCL64 cell proliferation and did not enhance TGF-beta 2-mediated (62 pg/ml to 250 pg/ml) inhibition of CCL64 or thymocyte proliferation. Hydrocortisone inhibited the one-way MLR in the concentration range present in AH and, at 10 ng/ml, inhibited the ability of epidermal cells to present TAA for elicitation of delayed-type hypersensitivity in tumor-immune mice. CONCLUSIONS: These results show that AH contains biologically relevant concentrations of glucocorticoids and that CBG is relatively absent so that glucocorticoids present are largely free, and they suggest that regional sites take advantage of the activities of multiple factors to maintain an immune-privileged status.

Tumor antigen presentation by murine epidermal cells.

The ability of epidermal Langerhans cells to present Ag for CD4-dependent immunity is well documented, and it has been hypothesized that Langerhans cells participate in the generation of immunity against incipient epidermal neoplasms by presentation of tumor-associated Ag in situ. This study examined the ability of murine epidermal cells (EC) to present tumor-associated Ag for the induction of in vivo antitumor immunity. Murine epidermal cells were deleted of Thy-1-bearing cells, cultured in 50 U/ml granulocyte-macrophage-CSF for 14 to 18 h, and pulsed with tumor fragments (TF) derived from S1509a-fibrosarcoma cells. These TF-pulsed EC were injected s.c. into syngeneic recipients at weekly intervals for a total of three immunizations and challenged with viable S1509a tumor cells 1 wk after the last immunization. Control animals received TF-pulsed allogeneic EC or EC treated identically but not pulsed with TF. EC that were pulsed with tumor cell fragments were able to induce protective immunity to tumor growth in vivo and to immunize for a significant delayed-type hypersensitivity response to injected tumor cells. The induction of antitumor immunity with TF-pulsed EC was genetically restricted, and culture of EC in granulocyte-macrophage-CSF was required for development of significant immunity. Furthermore, deletion of I-A+ cells by antibody and complement-mediated lysis eliminated the generation of immunity. Thus, I-A+ epidermal cells are capable of presenting S1509a tumor Ag for the generation of protective antitumor immunity in vivo.

Aqueous humor contains transforming growth factor-beta and a small (less than 3500 daltons) inhibitor of thymocyte proliferation.

The anterior chamber of the eye is an immunologically privileged site in which allografts survive longer than at other body sites. In this regard, it is relevant that aqueous humor (AH) inhibits lymphocyte proliferation. In order to analyze AH for specific substances that inhibit thymocyte proliferation, samples of human AH, murine AH, and rhesus monkey AH were added to cultures of thymocytes stimulated by IL-1 or IL-2 in the presence of PHA. All samples of AH tested had potent inhibitory activity on thymocyte proliferation in this system. Inhibitory activity was lost by heating AH to 80 degrees C for 1 h. Dialysis of murine AH indicated that species smaller than 3500 Da were capable of mediating this activity; we have termed the factor(s) responsible for this "small inhibitory factor(s) of AH." Retentate, containing species larger than 3500 Da, retained inhibitory activity, but less than nondialyzed AH. Assays for PGE2 demonstrated that murine and human AH contained small quantities of PGE2. These quantities were insufficient to inhibit thymocyte proliferation in our assay system. Furthermore, AH from mice treatend with indomethacin had full inhibitory activity. Assays for transforming growth factor beta (TGF-beta) after acid activation demonstrated significant quantities of latent TGF-beta within human and murine AH which could be largely neutralized by antisera to TGF-beta. Active TGF-beta "activity" was also present without acid activation in samples of AH at a level approximately 20% that of latent TGF-beta. However, most of this "activity" could not be neutralized by antisera to TGF-beta. AH contains factors capable of limiting thymocyte proliferation.