Intratumoral CD40 stimulating therapy in patients with advanced cancer

CD40-CD40L interaction activates DCs to become highly efficient APCs and skews the adaptive immune response towards a Th I phenotype driving cytotoxic T cells, M1 macrophages and natural killer cells. Furthermore, engagement of CD40L to CD40 positive cancer cells can have direct anti-proliferative effects, induce apoptosis and increase expression of MHC and other co-stimulatory molecules, thereby enhancing cancer cell recognition. Hence, activating the CD40-CD40L pathway may lead to several potential anti-tumoral effects.  In this thesis we evaluated activation of the CD40-CD40L pathway in patients with solid cancer by investigating three medicinal products administered mainly through intratumoral injection: ADC1013 - an agonistic CD40 antibody, AdCD40L - a replication deficient adenovirus carrying the gene for CD40L and LOAd703 - an oncolytic adenovirus carrying two immunostimulatory genes: TMZ-CD40L and 4-1BBL.  In paper I, ADC-1013 was investigated in patients with metastatic cancer (n=23) in a phase I trial. ADC-1013 was injected intratumorally (n=18) or intravenously (n=5).  AdCD40L was investigated in  a phase I/II study reported in paper II and III, respectively. In one cohort (paper II), patients with metastatic malignant melanoma (n=9) were treated with four weekly intratumoral injections with AdCD40L preceded by radiotherapy (single fraction 8 Gy) of the metastasis to subsequently be injected. Concomitant low dose cyclophosphamide was administered before the first and fourth intratumoral injection. In another cohort (paper III), patients with metastatic non melanoma solid cancer (n=6) were treated with the same schedule except from radiotherapy. Paper III also reports the results of the first-ever patient treated with AdCD40L.  In paper IV, the preliminary results of phase I of a phase I/II study investigating LOAd703 administered intratumorally at a two-week interval are presented. LOAd703 was given as an add-on to standard-of-care chemotherapy, or with gemcitabine conditioning in patients having received established treatments. Patients (n=9) had locally advanced or metastatic pancreatic cancer, metastatic ovarian cancer or colorectal cancer.  We conclude that treatment with all three medicinal products was safe and tolerable. For ADC-1013, the therapeutic ratio seemed to be more favorable for intratumoral injections into superficial metastases compared to deep metastases. We demonstrated that AdCD40L can be combined with radiotherapy without increasing toxicity although radiotherapy did not enhance treatment efficacy. Further, LOAd703 was safe to combine with chemotherapy. Although the number of patients treated in each trial was limited, and almost all patients were considered refractory to standard treatment at inclusion, some patients seemed to benefit from treatment which is encouraging.

Development and validation of a multi-dimensional diagnosis-based comorbidity index that improves prediction of death in men with prostate cancer: Nationwide, population-based register study.

Assessment of comorbidity is crucial for confounding adjustment and prediction of mortality in register-based studies, but the commonly used Charlson comorbidity index is not sufficiently predictive. We aimed to develop a multidimensional diagnosis-based comorbidity index (MDCI) that captures comorbidity better than the Charlson Comorbidity index. The index was developed based on 286,688 men free of prostate cancer randomly selected from the Swedish general population, and validated in 54,539 men without and 68,357 men with prostate cancer. All ICD-10 codes from inpatient and outpatient discharges during 10 years prior to the index date were used to define variables indicating frequency of code occurrence, recency, and total duration of related hospital admissions. Penalized Cox regression was used to predict 10-year all-cause mortality. The MDCI predicted risk of death better than the Charlson comorbidity index, with a c-index of 0.756 (95% confidence interval [CI] = 0.751, 0.762) vs 0.688 (95% CI = 0.683, 0.693) in the validation cohort of men without prostate cancer. Men in the lowest vs highest MDCI quartile had distinctively different survival in the validation cohort of men with prostate cancer, with an overall hazard ratio [HR] of 5.08 (95% CI = 4.90, 5.26). This was also consistent within strata of age and Charlson comorbidity index, e.g. HR = 5.90 (95% CI = 4.65, 7.50) in men younger than 60 years with CCI 0. These results indicate that comorbidity assessment in register-based studies can be improved by use of all ICD-10 codes and taking related frequency, recency, and duration of hospital admissions into account

Gemcitabine reduces MDSCs, tregs and TGF beta-1 while restoring the teff/treg ratio in patients with pancreatic cancer

Background: Cancer immunotherapy can be potentiated by conditioning regimens such as cyclophosphamide, which reduces the level of regulatory T cells (tregs). However, myeloid suppressive cells are still remaining. Accordingly to previous reports, gemcitabine improves immune status of cancer patients. In this study, the role of gemcitabine was further explored to map its immunological target cells and molecules in patients with pancreatic cancer. Methods: Patient blood was investigated by flow cytometry and cytokine arrays at different time points during gemcitabine treatment. Results: The patients had elevated myeloid-derived suppressor cells (MDSCs), and Tregs at diagnosis. Myeloid cells were in general decreased by gemcitabine. The granulocytic MDSCs were significantly reduced while monocytic MDSCs were not affected. In vitro, monocytes responding to IL-6 by STAT3 phosphorylation were prevented to respond in gemcitabine medium. However, gemcitabine could not prevent STAT3 phosphorylation in IL-6-treated tumor cell lines. TGF beta-1 was significantly reduced after only one treatment and continued to decrease. At the same time, the effector T cell:Treg ratio was increased and the effector T cells had full proliferative capacity during the gemcitabine cycle. However, after a resting period, the level of suppressor cells and TGF beta-1 had been restored showing the importance of continuous conditioning. Conclusions: Gemcitabine regulates the immune system in patients with pancreatic cancer including MDSCs, Tregs and molecules such as TGF beta-1 but does not hamper the ability of effector lymphocytes to expand to stimuli. Hence, it may be of high interest to use gemcitabine as a conditioning strategy together with immunotherapy

Choice of imputation method for missing metastatic status affected estimates of metastatic prostate cancer incidence.

OBJECTIVES: To study how handling missing data on M stage in a clinical cancer register affects estimates of incidence of metastatic prostate cancer. STUDY DESIGN AND SETTING: Estimates of age-standardized incidence of metastatic prostate cancer were obtained by use of data in a population-based clinical cancer register in Sweden and using four methods for imputation of missing M stage. Adjusted survival was used to compare men with known and imputed M stage. RESULTS: The proportion of men with missing M stage was high (66%) and varied according to risk group and over calendar time. The estimated incidence of metastatic disease varied depending on imputation method, with all methods indicating a decreasing incidence over time. A combination of deterministic imputation and multiple imputation produced adjusted survival curves for men with imputed M stage that best resembled the survival for men with known M stage. CONCLUSIONS: Plausible estimates of incidence of metastatic prostate cancer in clinical cancer registers can be obtained by use of a combination of deterministic imputation of missing M stage and multiple imputation

Survival by the multi-dimensional diagnosis-based comorbidity indices (MDCI).

Developed using 10 years of follow-up for mortality vs the Charlson comorbidity index (CCI) in the validation cohort of comparison men. (PDF)</p

Overview of the code extraction and creation of predictors.

Overview of the code extraction and creation of predictors.</p

Calibration plots.

Observed 10-year mortality risk compared to predicted risk based on the MDCI or the Charlson comorbidity index among 54,539 men without prostate cancer and 68,357 men with prostate cancer. In each cohort, the calibration plot was obtained by computing the predicted 10-year survival probability for each individual using a Cox proportional hazards model including the MDCI or Charlson comorbidity index, respectively as predictor, and a corresponding estimate of the baseline hazard function. The observed survival probability was computed as the average 10-year survival estimated by the Kaplan-Meier curve within the intervals of the predicted survival probabilities using the cutoffs 0%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% and 100%. The predicted survival probability was similarly computed as the average of all individual survival probabilities among individuals within each interval. Probability intervals containing zero individuals are not shown.</p

Calibration plots.

Observed 1, 5, and 10-year mortality risk compared to predicted risk based on the MDCI developed using 1, 5, and 10 years of follow-up for mortality, respectively, or the CCI. (PDF)</p

Baseline characteristics of the development cohort and the two validation cohorts in Prostate Cancer data Base Sweden (PCBaSe) 5.

Baseline characteristics of the development cohort and the two validation cohorts in Prostate Cancer data Base Sweden (PCBaSe) 5.</p