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1.  Mitochondria “fuel” breast cancer metabolism: Fifteen markers of mitochondrial biogenesis label epithelial cancer cells, but are excluded from adjacent stromal cells 
Cell Cycle  2012;11(23):4390-4401.
Here, we present new genetic and morphological evidence that human tumors consist of two distinct metabolic compartments. First, re-analysis of genome-wide transcriptional profiling data revealed that > 95 gene transcripts associated with mitochondrial biogenesis and/or mitochondrial translation were significantly elevated in human breast cancer cells, as compared with adjacent stromal tissue. Remarkably, nearly 40 of these upregulated gene transcripts were mitochondrial ribosomal proteins (MRPs), functionally associated with mitochondrial translation of protein components of the OXPHOS complex. Second, during validation by immunohistochemistry, we observed that antibodies directed against 15 markers of mitochondrial biogenesis and/or mitochondrial translation (AKAP1, GOLPH3, GOLPH3L, MCT1, MRPL40, MRPS7, MRPS15, MRPS22, NRF1, NRF2, PGC1-α, POLRMT, TFAM, TIMM9 and TOMM70A) selectively labeled epithelial breast cancer cells. These same mitochondrial markers were largely absent or excluded from adjacent tumor stromal cells. Finally, markers of mitochondrial lipid synthesis (GOLPH3) and mitochondrial translation (POLRMT) were associated with poor clinical outcome in human breast cancer patients. Thus, we conclude that human breast cancers contain two distinct metabolic compartments—a glycolytic tumor stroma, which surrounds oxidative epithelial cancer cells—that are mitochondria-rich. The co-existence of these two compartments is indicative of metabolic symbiosis between epithelial cancer cells and their surrounding stroma. As such, epithelial breast cancer cells should be viewed as predatory metabolic “parasites,” which undergo anabolic reprogramming to amplify their mitochondrial “power.” This notion is consistent with the observation that the anti-malarial agent chloroquine may be an effective anticancer agent. New anticancer therapies should be developed to target mitochondrial biogenesis and/or mitochondrial translation in human cancer cells.
doi:10.4161/cc.22777
PMCID: PMC3552922  PMID: 23172368
two-compartment tumor metabolism; mitochondria; oxidative phosphorylation (OXPHOS); mitochondrial biogenesis; mitochondrial translation; cancer metabolism; metabolic reprogramming
2.  Downregulation of stromal BRCA1 drives breast cancer tumor growth via upregulation of HIF-1α, autophagy and ketone body production 
Cell Cycle  2012;11(22):4167-4173.
Our recent studies have mechanistically demonstrated that cancer-associated fibroblasts (CAFs) produce energy-rich metabolites that functionally support the growth of cancer cells. Also, several authors have demonstrated that DNA instability in the tumor stroma greatly contributes to carcinogenesis. To further test this hypothesis, we stably knocked-down BRCA1 expression in human hTERT-immortalized fibroblasts (shBRCA1) using an shRNA lentiviral approach. As expected, shBRCA1 fibroblasts displayed an elevated growth rate. Using immunofluorescence and immunoblot analysis, shBRCA1 fibroblasts demonstrated an increase in markers of autophagy and mitophagy. Most notably, shBRCA1 fibroblasts also displayed an elevation of HIF-1α expression. In accordance with these findings, shBRCA1 fibroblasts showed a 5.5-fold increase in ketone body production; ketone bodies function as high-energy mitochondrial fuels. This is consistent with the onset of mitochondrial dysfunction in BRCA1-deficient fibroblasts. Conversely, after 48 h of co-culturing shBRCA1 fibroblasts with a human breast cancer cell line (MDA-MB-231 cell), mitochondrial activity was enhanced in these epithelial cancer cells. Interestingly, our preclinical studies using xenografts demonstrated that shBRCA1 fibroblasts induced an ~2.2-fold increase in tumor growth when co-injected with MDA-MB-231 cells into nude mice. We conclude that a BRCA1 deficiency in the tumor stroma metabolically promotes cancer progression, via ketone production.
doi:10.4161/cc.22316
PMCID: PMC3524212  PMID: 23047605
BRCA1; cancer metabolism; stromal fibroblasts; ketone bodies; HIF1; mitochondrial OXPHOS; autophagy; mitophagy
3.  Mitochondrial biogenesis in epithelial cancer cells promotes breast cancer tumor growth and confers autophagy resistance 
Cell Cycle  2012;11(22):4174-4180.
Here, we set out to test the novel hypothesis that increased mitochondrial biogenesis in epithelial cancer cells would “fuel” enhanced tumor growth. For this purpose, we generated MDA-MB-231 cells (a triple-negative human breast cancer cell line) overexpressing PGC-1α and MitoNEET, which are established molecules that drive mitochondrial biogenesis and increased mitochondrial oxidative phosphorylation (OXPHOS). Interestingly, both PGC-1α and MitoNEET increased the abundance of OXPHOS protein complexes, conferred autophagy resistance under conditions of starvation and increased tumor growth by up to ~3-fold. However, this increase in tumor growth was independent of neo-angiogenesis, as assessed by immunostaining and quantitation of vessel density using CD31 antibodies. Quantitatively similar increases in tumor growth were also observed by overexpression of PGC-1β and POLRMT in MDA-MB-231 cells, which are also responsible for mediating increased mitochondrial biogenesis. Thus, we propose that increased mitochondrial “power” in epithelial cancer cells oncogenically promotes tumor growth by conferring autophagy resistance. As such, PGC-1α, PGC-1β, mitoNEET and POLRMT should all be considered as tumor promoters or “metabolic oncogenes.” Our results are consistent with numerous previous clinical studies showing that metformin (a weak mitochondrial “poison”) prevents the onset of nearly all types of human cancers in diabetic patients. Therefore, metformin (a complex I inhibitor) and other mitochondrial inhibitors should be developed as novel anticancer therapies, targeting mitochondrial metabolism in cancer cells.
doi:10.4161/cc.22376
PMCID: PMC3524213  PMID: 23070475
cancer metabolism; mitochondrial biogenesis; oxidative phosphorylation; OXPHOS; autophagy resistance; angiogenesis; two-compartment tumor metabolism
4.  Effects of Palm Vitamin E on Bone-Formation-Related Gene Expression in Nicotine-Treated Rats 
The study determines the effects of palm vitamin E on the gene expression of bone-formation-related genes in nicotine-treated rats. Male rats were divided into three groups: normal saline olive oil (NSO), nicotine olive oil (NO), and nicotine palm vitamin E (NE). The treatment was carried out in 2 phases. During the first 2 months, the NSO group received normal saline while the NO and NE groups received nicotine 7 mg/kg, 6 days a week, intraperitoneally. The following 2 months, normal saline and nicotine administration was stopped and was replaced with oral supplementation of olive oil for the NSO and NO groups and oral supplementation of palm vitamin E (60 mg/kg) for the NE group. Both femurs were harvested to determine the gene expression of bone morphogenetic protein-2 (BMP-2), Osterix (OSX), and Runt-related transcription factor 2 (RUNX2). Nicotine significantly downregulated the gene expression. This effect was reversed by palm vitamin E treatment. In conclusion, palm vitamin E may play a role in osteoblast differentiation and can be considered as an anabolic agent to treat nicotine-induced osteoporosis.
doi:10.1155/2012/656025
PMCID: PMC3434599  PMID: 23049610
5.  Stage I seminoma: treatment outcome at King Hussein Cancer Center in Jordan 
BMC Urology  2012;12:10.
Background
The aim of this report is to address treatment outcomes of patients with early-stage seminoma in a single institution with special reference to patients with history of surgical violation of the scrotum.
Methods
Seventy four patients with pure seminoma were treated at King Hussein Cancer Center (Amman, Jordan) between 2003 and 2010. All patients underwent orchiectomy. All but 3 patients received adjuvant radiotherapy. Patients who underwent surgical violation of the scrotum prior to referral were managed by further excision or irradiation of the scrotal scar. The follow-up ranged from 1 to 200 months (mean, 33 months).
Results
At the time of follow-up; all but one patient remain alive. The 3-year relapse-free survival for the entire cohort was 95.9%. Three patients developed relapse, all of whom received adjuvant irradiation following inguinal orchiectomy and initially harbored tumors larger than 4 cm upon pathological examination. Median time to relapse was 14 months (range, 8–25 months). None were associated with elevated tumor markers prior to detection of relapse. All but one patient were successfully salvaged by chemotherapy.
Conclusions
Our results confirm the excellent prognosis of patients with early-stage seminoma treated by orchiectomy and adjuvant radiotherapy in a developing country. Although all patients who developed relapse demonstrated adverse pathological findings upon initial assessment, no consistent predictor of relapse was found. Scrotal scar re-excision or irradiation in patients with prior history of surgical violation of the scrotum are effective measures in preventing local failure.
doi:10.1186/1471-2490-12-10
PMCID: PMC3419628  PMID: 22531005

Results 1-5 (5)