Prostate cancer cells survive anti-androgen and mitochondrial metabolic inhibitors by modulating glycolysis and mitochondrial metabolic activities.

BACKGROUND: Most cancer cells are more glycolytic even under aerobic conditions compared with their normal counterparts. Recent evidence of tumor cell metabolism, however, shows that some tumors also increase mitochondrial oxidative phosphorylation (ox-phos) at some disease states during progression and/or development of drug resistance. Our data show that anti-androgen enzalutamide (ENZA) resistant prostate cancer (PCa) cells use more mitochondrial metabolism leading to higher ox-phos as compared to the ENZA-sensitive cells and can become vulnerable to mitochondrial metabolism targeted therapies. METHODS: Seahorse assay, mass spectrometry and high resolution fluorescence confocal microscopy coupled with image analysis has been used to compare mitochondrial metabolism in ENZA-treated and -untreated anti-androgen-sensitive LNCaP and -resistant C4-2, CWR22ν1, and PCa2b cells. Ex vivo fluorescence microscopy and image analysis has been standardized to monitor mitochondrial electron transport (ETS) activity that likely increases ox-phos in circulating tumor cells (CTCs) isolated fom patients undergoing AR-targeted therapies. RESULTS: Our data show that PCa cells that are resistant to anti-androgen ENZA switch from glycolysis to ox-phos leading to an increased ETS activity. ENZA pretreated cells are more vulnerable to ETS component complex I inhibitor IACS-010759 (IACS) and mitochondrial glutaminase inhibitor CB-839 that reduces glutamate supply to tricarboxylic acid cycle. CTCs isolated from 6 of 20 patient blood samples showed relatively higher ETS activity than the rest of the patients. All six patients have developed ENZA resistance within less than 6 months of the sample collection. CONCLUSION: The enhanced growth inhibitory effects of mitochondrial metabolic inhibitors IACS and CB-839 in ENZA pretreated PCa cells provides a rationale for designing a drug combination trial. Patients can be selected for such trials by monitoring the mitochondrial ETS activities in their CTCs to maximize success.

Colon Cancer in Patients Under 25 Years Old: A Different Disease?

BACKGROUND: The aim of this study was to compare the stage-for-stage overall (OS) and recurrence-free (RFS) survival between adult and pediatric/adolescent colon cancer patients. STUDY DESIGN: A retrospective review of pediatric/adolescent patients less than 25 years old, treated between 1991 and 2017 at University of Texas MD Anderson Cancer Center, was compared with a prospectively maintained database of adult patients. Outcomes variables were compared, and OS and RFS were estimated using the Kaplan-Meier method and compared between groups using the log rank test and multivariable Cox models. RESULTS: The cohort contained 94 pediatric patients and 765 adult patients. Overall, the 3-year OS rates for adult and pediatric patients, respectively, were 90% and 41.92% (95% CI 87% to 92%) (p < 0.0001), and the 3-year RFS rates were 78% and 32% (p < 0.0001). The stage-for-stage 5-year OS rates for adult vs pediatric patients were: Stage 1: 96% vs 100% (p = 0.793); stage 2: 90% vs 64% (p < 0.0001); stage 3: 85% vs 58% (p < 0.0001); stage 4; 55% vs 16% (p < 0.0001). The stage-for-stage 5-year RFS rates for adults vs children were: stage 1: 95% vs 100%; stage 2: 85% vs 55% (p = 0.0002); stage 3: 73% vs 31% (p < 0.0001); stage 4: 27% vs 5% (p < 0.0001). Pediatric/adolescent patients had a higher risk of recurrence or death than adult patients on multivariate analysis (hazard ratio [HR] 2.312, 95% CI: 1.615 to 3.313 (p < 0.0001). Peritoneal metastasis was significantly higher in pediatric patients. (p = 0.00001) CONCLUSIONS: Stage-for-stage, pediatric/adolescent patients had shorter 3- and 5-year OS and RFS rates than adult patients. Peritoneal disease and carcinomatosis were significantly higher in pediatric, adolescent, and young adult patients less than 25 years old. Predisposing conditions, such as polyposis or congenital colon disease, did not contribute to this difference.

Rate of bilirubin regression after stenting in malignant biliary obstruction for the initiation of chemotherapy: how soon should we repeat endoscopic retrograde cholangiopancreatography?

BACKGROUND: This study was conducted to evaluate the rate of regression of bilirubin after stent placement for malignant biliary obstruction. METHODS: Records were reviewed from October 2002 to September 2005 for patients who underwent endoscopic retrograde cholangiopancreatography with stent placement. The time to achieve a bilirubin level or=10 mg/dL (6 weeks) compared with those who had prestent bilirubin levels <10 mg/dL (3 weeks). The following variables were identified as statistically significant: prestent bilirubin level, stricture location, liver metastasis, and INR. The cancer type, recent chemotherapy, stent type and diameter, and sphincterotomy were not statistically significant variables. CONCLUSIONS: The rate of bilirubin normalization after biliary stenting was highly dependent on the prestent bilirubin level. Endoscopic intervention should be considered in patients who fail to achieve adequate normalization of serum bilirubin in 6 weeks if prestent bilirubin level was >or=10 mg/dL and in 3 weeks if their prestent bilirubin level was <10 mg/dL. Independent variables, such as diffuse liver metastases, stricture outside the common bile duct, and elevated INR had predictive value for bilirubin normalization.

Cancer patients with markedly elevated B-type natriuretic peptide may not have volume overload.

OBJECTIVES: Elevated B-type natriuretic peptide (BNP) levels are established as a marker for volume overload and left ventricular (LV) dysfunction in patients with predominately cardiac diseases. Little is known about markedly elevated BNP values in patients with multiple comorbidities. METHODS: A total of 99 patients, admitted to M. D. Anderson Cancer Center, were identified as having a BNP value >1000 pg/mL during the year 2003. Clinical characteristics, including the presence of volume overload and sepsis, as well as echocardiographic parameters were measured. Principal outcome was defined as 30-day mortality. RESULTS: The median BNP (pg/mL) of the group was 2270 (range, 1010-5000), and there was no association between elevation of the BNP level and the presence of volume overload or LV dysfunction (P = not significant). The large majority of patients (n = 71, 72%) had no volume overload and normal or nearly normal LV function (n = 60, 61%). A majority were also identified as having sepsis (n = 52, 53%). There was no echocardiographic parameter that consistently correlated with BNP levels or volume overload. There was a highly significant association with sepsis and mortality in patients with markedly elevated BNP values, and this conferred a 2.71-fold increased risk of mortality. CONCLUSIONS: In patients admitted with multiple comorbidities and markedly elevated BNP values, there is no significant association with clinical evidence of volume overload or LV dysfunction. An elevated BNP level in patients with sepsis was significantly associated with mortality.

Direct tandem mass spectrometry reveals limitations in protein profiling experiments for plasma biomarker discovery.

The low molecular weight plasma proteome and its biological relevance are not well defined; therefore, experiments were conducted to directly sequence and identify peptides observed in plasma and serum protein profiles. Protein fractionation, matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) profiling, and liquid-chromatography coupled to MALDI tandem mass spectrometry (MS/MS) sequencing were used to analyze the low molecular weight proteome of heparinized plasma. Four fractionation techniques using functionally derivatized 96-well plates were used to extract peptides from plasma. Tandem TOF was successful for identifying peptides up to m/z 5500 with no prior knowledge of the sequence and was also used to verify the sequence assignments for larger ion signals. The peptides (n>250) sequenced in these profiles came from a surprisingly small number of proteins (n approximately 20), which were all common to plasma, including fibrinogen, complement components, antiproteases, and carrier proteins. The cleavage patterns were consistent with those of known plasma proteases, including initial cleavages by thrombin, plasmin and complement proteins, followed by aminopeptidase and carboxypeptidase activity. On the basis of these data, we discuss limitations in biomarker discovery in the low molecular weight plasma or serum proteome using crude fractionation coupled to MALDI-MS profiling.

Plasma protein profiling for diagnosis of pancreatic cancer reveals the presence of host response proteins.

Plasma protein profiling using separations coupled to matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) has great potential in translational research; it can be used for biomarker discovery and contribute to disease diagnosis and therapy. Previously reported biomarker searches have been done solely by MS protein profiling followed by bioinformatics analysis of the data. To add to current methods, we tested an alternative strategy for plasma protein profiling using pancreatic cancer as the model. First, offline solid-phase extraction is done with 96-well plates to fractionate and partially purify the proteins. Then, multiple profiling and identification experiments can be conducted on the same protein fractions because only 5% of the fractions are used for MALDI MS profiling. After MALDI MS analysis, the mass spectra are normalized and subjected to a peak detection algorithm. Over three sets of mass spectra acquired using different instrument variables, approximately 400 unique ion signals were detected. Classification schemes employing as many as eight individual peaks were developed using a training set with 123 members (82 cancer patients) and a blinded validation set with 125 members (57 cancer patients). The sensitivity of the study was 88%, but the specificity was significantly lower, 75%. The reason for the low specificity becomes apparent upon protein identification of the ion signals used for the classification. The identifications reveal only common serum proteins and components of the acute phase response, including serum amyloid A, alpha-1-antitrypsin, alpha-1-antichymotrypsin, and inter-alpha-trypsin inhibitor.

A comprehensive approach to the analysis of matrix-assisted laser desorption/ionization-time of flight proteomics spectra from serum samples.

For our analysis of the data from the First Annual Proteomics Data Mining Conference, we attempted to discriminate between 24 disease spectra (group A) and 17 normal spectra (group B). First, we processed the raw spectra by (i) correcting for additive sinusoidal noise (periodic on the time scale) affecting most spectra, (ii) correcting for the overall baseline level, (iii) normalizing, (iv) recombining fractions, and (v) using variable-width windows for data reduction. Also, we identified a set of polymeric peaks (at multiples of 180.6 Da) that is present in several normal spectra (B1-B8). After data processing, we found the intensities at the following mass to charge (m/z) values to be useful discriminators: 3077, 12 886 and 74 263. Using these values, we were able to achieve an overall classification accuracy of 38/41 (92.6%). Perfect classification could be achieved by adding two additional peaks, at 2476 and 6955. We identified these values by applying a genetic algorithm to a filtered list of m/z values using Mahalanobis distance between the group means as a fitness function.

Quality control and peak finding for proteomics data collected from nipple aspirate fluid by surface-enhanced laser desorption and ionization.

BACKGROUND: Recently, researchers have been using mass spectroscopy to study cancer. For use of proteomics spectra in a clinical setting, stringent quality-control procedures will be needed. METHODS: We pooled samples of nipple aspirate fluid from healthy breasts and breasts with cancer to prepare a control sample. Aliquots of the control sample were used on two spots on each of three IMAC ProteinChip arrays (Ciphergen Biosystems, Inc.) on 4 successive days to generate 24 SELDI spectra. In 36 subsequent experiments, the control sample was applied to two spots of each ProteinChip array, and the resulting spectra were analyzed to determine how closely they agreed with the original 24 spectra. RESULTS: We describe novel algorithms that (a) locate peaks in unprocessed proteomics spectra and (b) iteratively combine peak detection with baseline correction. These algorithms detected approximately 200 peaks per spectrum, 68 of which are detected in all 24 original spectra. The peaks were highly correlated across samples. Moreover, we could explain 80% of the variance, using only six principal components. Using a criterion that rejects a chip if the Mahalanobis distance from both control spectra to the center of the six-dimensional principal component space exceeds the 95% confidence limit threshold, we rejected 5 of the 36 chips. CONCLUSIONS: Mahalanobis distance in principal component space provides a method for assessing the reproducibility of proteomics spectra that is robust, effective, easily computed, and statistically sound.

Adaptive randomized study of idarubicin and cytarabine versus troxacitabine and cytarabine versus troxacitabine and idarubicin in untreated patients 50 years or older with adverse karyotype acute myeloid leukemia.

PURPOSE: Troxacitabine has activity in refractory myeloid leukemia, either as a single agent or when combined with cytarabine (ara-C) or with idarubicin. A prospective, randomized study was conducted in patients aged 50 years or older with untreated, adverse karyotype, acute myeloid leukemia (AML) to assess troxacitabine-based regimes as induction therapy. PATIENTS AND METHODS: Patients were randomized to receive idarubicin and ara-C (IA) versus troxacitabine and ara-C (TA) versus troxacitabine and idarubicin (TI). A Bayesian design was used to adaptively randomly assign patients to treatment. Thus, although there was initially an equal chance for randomization to IA, TA, or TI, treatment arms with a higher success rate progressively received a greater proportion of patients. RESULTS: Thirty-four patients were treated. Randomization to TI stopped after five patients and randomization to TA stopped after 11 patients. Defining success as complete remission (CR) that occurred within 49 days of starting treatment, success rates were 55% (10 of 18 patients) with IA, 27% (three of 11 patients) with TA, and 0% (zero of five patients) with TI. Because three CRs occurred after day 49, final CR rates were 55% (10 of 18 patients) with IA, 45% (five of 11 patients) with TA, and 20% (one of five patients) with TI. The probability that TA was inferior to IA was 70%, with a 5% probability that TA would have a 20% higher CR rate than IA. Survival was equivalent with all three regimens. CONCLUSION: Neither troxacitabine combination was superior to IA in elderly patients with previously untreated adverse karyotype AML.