Corrigendum: Development of sandwich dot-ELISA for specific detection of Ochratoxin A and its application on to contaminated cereal grains originating from India

[This corrects the article DOI: 10.3389/fmicb.2015.00511.].

Evaluation of Cardiac, Autonomic Functions in Ambulant Patients with Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked genetic disorder caused by dystrophin gene mutation resulting in muscle weakness, motor delays, difficulty in standing, and inability to walk by 12 years. As disease progresses, it leads to cardiac and respiratory failure. Evaluation of cardiac autonomic status and echocardiography in DMD patients at a young age can be a potential biomarker to assess disease progression. This study aimed to investigate the younger DMD population of 5-11years of age with mild to moderate cardiac involvement for early detection using non-invasive and cost-effective tools. Genetically confirmed male DMD patients, aged 5-11 years (n = 47), screened from the outpatient department of a tertiary neuroscience institution were subjected to heart rate variability and echocardiographic analysis, and values were correlated with their clinical variables. DMD patients showed a significantly higher difference in HR, interventricular septum, E m/s, and E-wave to A-wave (E/A) ratio than normal values (p < 0.001). Significantly higher HR indicates initial sinus tachycardia and decreased IVD (d), and increased E m/s and E/A ratio mark the onset of cardiac symptoms in DMD patients even though its chamber dimension remains normal and are associated with cardiac muscle fibrosis.

Cadmium toxicity in medicinal plants: An overview of the tolerance strategies, biotechnological and omics approaches to alleviate metal stress

Medicinal plants, an important source of herbal medicine, are gaining more demand with the growing human needs in recent times. However, these medicinal plants have been recognized as one of the possible sources of heavy metal toxicity in humans as these medicinal plants are exposed to cadmium-rich soil and water because of extensive industrial and agricultural operations. Cadmium (Cd) is an extremely hazardous metal that has a deleterious impact on plant development and productivity. These plants uptake Cd by symplastic, apoplastic, or via specialized transporters such as HMA, MTPs, NRAMP, ZIP, and ZRT-IRT-like proteins. Cd exerts its effect by producing reactive oxygen species (ROS) and interfere with a range of metabolic and physiological pathways. Studies have shown that it has detrimental effects on various plant growth stages like germination, vegetative and reproductive stages by analyzing the anatomical, morphological and biochemical changes (changes in photosynthetic machinery and membrane permeability). Also, plants respond to Cd toxicity by using various enzymatic and non-enzymatic antioxidant systems. Furthermore, the ROS generated due to the heavy metal stress alters the genes that are actively involved in signal transduction. Thus, the biosynthetic pathway of the important secondary metabolite is altered thereby affecting the synthesis of secondary metabolites either by enhancing or suppressing the metabolite production. The present review discusses the abundance of Cd and its incorporation, accumulation and translocation by plants, phytotoxic implications, and morphological, physiological, biochemical and molecular responses of medicinal plants to Cd toxicity. It explains the Cd detoxification mechanisms exhibited by the medicinal plants and further discusses the omics and biotechnological strategies such as genetic engineering and gene editing CRISPR- Cas 9 approach to ameliorate the Cd stress.

NANOTEX BONE Graft along with Fibula Flap in the Reconstruction of Segmental Mandibular Defect: Protocol for Pilot Clinical Trial

Introduction and objectives

Mandible reconstruction with vascularized fibula flap is the standard treatment for segmental mandibulectomy in patients with tumor or trauma. But the height of the fibula graft is insufficient for dental implant placement and prosthetic rehabilitation to replace the missing teeth, which in turn will compromise the functional efficiency and aesthetics of the patient. Although the bone height can be augmented through onlay grafting with iliac crest, it is associated with limitations like donor site morbidity and fast resorbability. This suggests the need for a synthetic biomaterial for vertical bone augmentation in implant dentistry.We have developed a biomimetic, porous, mechanically stable, and biodegradable nanocomposite named "NANOTEX BONE Graft" and its bone regeneration potential was evaluated in pre-clinical animal models. In this clinical trial, the safety as well as the efficacy of NANOTEX to augment new bone over fibula and further its ability to integrate with dental implants will be studied. The study has received the approval of the Ethics Committee of Amrita Institute of Medical Sciences and Central Drugs Standard Control Organization (CDSCO), India.

Methods

We have designed a prospective, single-center, non-randomized pilot clinical study. Patients with benign tumor or trauma indicated for mandibular reconstruction followed by implant rehabilitation will be included in the study. Eligible patients will be enrolled after obtaining informed consent. The study will be initiated and followed up as per defined timelines.

Highlights

Resection of benign mandibular tumours necessitates surgical removal of jaw bone and adjacent affected areas.The segmental mandibulectomy leaves the patient with functional impairments and aesthetic defects which in turn affect the quality of life.The standard treatment of reconstruction with vascularized fibula flap has challenge in achieving sufficient vertical bone height for implant placement and prosthetic rehabilitation.Alternate surgical techniques cause donor site morbidity and surgical complications.There is need for a synthetic biomaterial to be grafted over fibula for vertical bone augmentation.NANOTEX BONE Graft, a nanofibrous composite scaffold that mimics native bone, promote cell infiltration, neo-angiogenesis and new bone formation.Preclinical studies of NANOTEX in animal models showed bone tissue regeneration, better biodegradation in critical sized defects and efficient integration with dental implants.This clinical study propose to evaluate the safety and efficacy of NANOTEX bone graft augmented over fibula in bone regeneration and Titanium dental implant integration.

Monounsaturated and Diunsaturated Fatty Acids Sensitize Cervical Cancer to Radiation Therapy

Obesity induces numerous physiological changes that can impact cancer risk and patient response to therapy. Obese patients with cervical cancer have been reported to have superior outcomes following chemoradiotherapy, suggesting that free fatty acids (FFA) might enhance response to radiotherapy. Here, using preclinical models, we show that monounsaturated and diunsaturated FFAs (uFFA) radiosensitize cervical cancer through a novel p53-dependent mechanism. UFFAs signaled through PPARγ and p53 to promote lipid uptake, storage, and metabolism after radiotherapy. Stable isotope labeling confirmed that cervical cancer cells increase both catabolic and anabolic oleate metabolism in response to radiotherapy, with associated increases in dependence on mitochondrial fatty acid oxidation for survival. In vivo, supplementation with exogenous oleate suppressed tumor growth in xenografts after radiotherapy, an effect that could be partially mimicked in tumors from high fat diet-induced obese mice. These results suggest that supplementation with uFFAs may improve tumor responses to radiotherapy, particularly in p53 wild-type tumors.

SIGNIFICANCE

Metabolism of monounsaturated and diunsaturated fatty acids improves the efficacy of radiotherapy in cancer through modulation of p53 activity. See related commentary by Jungles and Green, p. 4513.

Region-based feature enhancement using channel-wise attention for classification of breast histopathological images

Breast histopathological image analysis at 400x magnification is essential for the determination of malignant breast tumours. But manual analysis of these images is tedious, subjective, error-prone and requires domain knowledge. To this end, computer-aided tools are gaining much attention in the recent past as it aids pathologists and save time. Furthermore, advances in computational power have leveraged the usage of computer tools. Yet, usage of computer-aided tools to analyse these images is challenging due to various reasons such as heterogeneity of malignant tumours, colour variations and presence of artefacts. Moreover, these images are captured at high resolutions which pose a major challenge to designing deep learning models as it demands high computational requirements. In this context, the present work proposes a new approach to efficiently and effectively extract features from these high-resolution images. In addition, at 400x magnification, the characteristics and structure of nuclei play a prominent role in the decision of malignancy. In this regard, the study introduces a novel CNN architecture called as CWA-Net that uses a colour channel attention module to enhance the features of the potential regions of interest such as nuclei. The developed model is qualitatively and quantitatively evaluated on private and public datasets and achieved an accuracy of 0.95% and 0.96%, respectively. The experimental evaluation demonstrates that the proposed method outperforms state-of-the-art methods on both datasets.

Recurrent Cylindroma of the Scalp: A Cytomorphological Evaluation at Fine Needle Aspiration Cytology

Specific diagnosis of adnexal tumours at fine needle aspiration cytology (FNAC) is challenging. In a recurrent scalp tumour, a startling array of lesions ranging from benign to malignant tumours fall into differential diagnosis. Accurate preoperative diagnosis is essential for planning management and to improve clinical outcome. Herein, we report a rare case of recurrent cylindroma of the scalp in a 62-year-old male patient. Cytology smears showed tight clusters of round to oval basaloid cells, few clusters with peripheral palisading. Basement membrane material was seen surrounding the cell clusters. FNAC diagnosis of a benign adnexal tumour, possibly cylindroma, was made. The diagnosis was confirmed at histopathology. We emphasize the decisive role of FNAC in arriving at an accurate diagnosis of a recurrent scalp tumour.

Histopathological spectrum of adult renal tumours: A Single center experience and review of literature

Background

Renal tumors constitute approximately 3% of all malignancies in adults. They form a heterogenous group with variable morphological, immunohistochemical, and molecular features.

Aim

The objective of this study was to analyze the spectrum of adult renal tumors at a tertiary care center and study the demographic and histomorphological features.

Materials and Methods

In this study, 55/87 nephrectomy specimens resected for adult renal tumors during a 1-year period were analyzed retrospectively.

Results

There were 4 benign (7.2%) and 51 (92.7%) malignant tumors. There was a male preponderance with a male: female ratio of 3.42:1. The tumors were seen to occur equally in both kidneys. The most common tumor was clear cell renal cell carcinoma (RCC), the conventional type accounting for 65.5% of our study group. There were one each of multilocular cystic renal neoplasm of low malignant potential, papillary RCC, chromophobe RCC, Mit family RCC, oncocytoma and angiomyolipoma and two clear cell papillary RCC during this 1-year period. Uncommon tumors included neuroendocrine carcinoma (1), epithelioid angiomyolipoma (1), mixed epithelial stromal tumor (1), Ewings sarcoma (2), and glomangioma (1). Five cases of urothelial carcinoma of renal pelvis/ureter also were present.

Conclusion

This article gives an overview of the spectrum of adult renal tumors at a tertiary care center with an in-depth literature review providing recent advances in each category of tumors.

Breast histopathological image analysis using image processing techniques for diagnostic puposes: A methodological review

Breast cancer in women is the second most common cancer worldwide. Early detection of breast cancer can reduce the risk of human life. Non-invasive techniques such as mammograms and ultrasound imaging are popularly used to detect the tumour. However, histopathological analysis is necessary to determine the malignancy of the tumour as it analyses the image at the cellular level. Manual analysis of these slides is time consuming, tedious, subjective and are susceptible to human errors. Also, at times the interpretation of these images are inconsistent between laboratories. Hence, a Computer-Aided Diagnostic system that can act as a decision support system is need of the hour. Moreover, recent developments in computational power and memory capacity led to the application of computer tools and medical image processing techniques to process and analyze breast cancer histopathological images. This review paper summarizes various traditional and deep learning based methods developed to analyze breast cancer histopathological images. Initially, the characteristics of breast cancer histopathological images are discussed. A detailed discussion on the various potential regions of interest is presented which is crucial for the development of Computer-Aided Diagnostic systems. We summarize the recent trends and choices made during the selection of medical image processing techniques. Finally, a detailed discussion on the various challenges involved in the analysis of BCHI is presented along with the future scope.

HPV transcript expression affects cervical cancer response to chemoradiation

Persistent HPV infection is causative for the majority of cervical cancer cases; however, current guidelines do not require HPV testing for newly diagnosed cervical cancer. Using an institutional cohort of 88 patients with cervical cancer treated uniformly with standard-of-care chemoradiation treatment (CRT) with prospectively collected clinical outcome data, we observed that patients with cervical tumors containing HPV genotypes other than HPV 16 have worse survival outcomes after CRT compared with patients with HPV 16⁺ tumors, consistent with previously published studies. Using RNA sequencing analysis, we quantified viral transcription efficiency and found higher levels of E6 and the alternative transcript E6*I in cervical tumors with HPV genotypes other than HPV 16. These findings were validated using whole transcriptome data from The Cancer Genome Atlas (n = 304). For the first time to our knowledge, transcript expression level of HPV E6*I was identified as a predictive biomarker of CRT outcome in our complete institutional data set (n = 88) and within the HPV 16⁺ subset (n = 36). In vitro characterization of HPV E6*I and E6 overexpression revealed that both induce CRT resistance through distinct mechanisms dependent upon p53–p21. Our findings suggest that high expression of E6*I and E6 may represent novel biomarkers of CRT efficacy, and these patients may benefit from alternative treatment strategies.

Multi-channel Chan-Vese model for unsupervised segmentation of nuclei from breast histopathological images

T he pathologist determines the malignancy of a breast tumor by studying the histopathological images. In particular, the characteristics and distribution of nuclei contribute greatly to the decision process. Hence, the segmentation of nuclei constitutes a crucial task in the classification of breast histopathological images. Manual analysis of these images is subjective, tedious and susceptible to human error. Consequently, the development of computer-aided diagnostic systems for analysing these images have become a vital factor in the domain of medical imaging. However, the usage of medical image processing techniques to segment nuclei is challenging due to the diverse structure of the cells, poor staining process, the occurrence of artifacts, etc. Although supervised computer-aided systems for nuclei segmentation is popular, it is dependent on the availability of standard annotated datasets. In this regard, this work presents an unsupervised method based on Chan-Vese model to segment nuclei from breast histopathological images. The proposed model utilizes multi-channel color information to efficiently segment the nuclei. Also, this study proposes a pre-processing step to select appropriate color channel such that it discriminates nuclei from the background region. An extensive evaluation of the proposed model on two challenging datasets demonstrates its validity and effectiveness.

Standardized Uptake Value for 18F-Fluorodeoxyglucose Is a Marker of Inflammatory State and Immune Infiltrate in Cervical Cancer

PURPOSE

Chemoradiotherapy for locally advanced cervical cancer fails in over a third of patients. Biomarkers with therapeutic implications are therefore needed. We investigated the relationship between an established prognostic marker, maximum standardized uptake value (SUV_max) on ¹⁸F-fluorodeoxyglucose positron emission tomography, and the inflammatory and immune state of cervical cancers.

EXPERIMENTAL DESIGN

An SUV_max most prognostic for freedom from progression (FFP) was identified and compared with known prognostic clinical variables in a cohort of 318 patients treated with definitive radiation with prospectively collected clinical data. Gene set enrichment analysis (GSEA) and CIBERSORT of whole-transcriptome data from 68 patients were used to identify biological pathways and immune cell subpopulations associated with high SUV_max. IHC using a tissue microarray (TMA, N = 82) was used to validate the CIBERSORT findings. The impact of macrophages on cervical cancer glucose metabolism was investigated in coculture experiments.

RESULTS

SUV_max <11.4 was most prognostic for FFP (P = 0.001). The GSEA showed that high SUV_max is associated with increased gene expression of inflammatory pathways, including JAK/STAT3 signaling. CIBERSORT and CD68 staining of the TMA showed high SUV_max tumors are characterized by a monocyte-predominant immune infiltrate. Coculture of cervical cancer cells with macrophages or macrophage-conditioned media altered glucose uptake, and IL6 and JAK/STAT3 signaling contribute to this effect.

CONCLUSIONS

SUV_max is a prognostic marker in cervical cancer that is associated with activation of inflammatory pathways and tumor infiltration of myeloid-derived immune cells, particularly macrophages. Macrophages contribute to changes in cervical cancer glucose metabolism.See related commentary by Williamson et al., p. 4136.

Integrating imaging and RNA-seq improves outcome prediction in cervical cancer

Approaches using a single type of data have been applied to classify human tumors. Here we integrate imaging features and transcriptomic data using a prospectively collected tumor bank. We demonstrate that increased maximum standardized uptake value on pretreatment 18F-fluorodeoxyglucose-positron emission tomography correlates with epithelial-to-mesenchymal transition (EMT) gene expression. We derived and validated 3 major molecular groups, namely squamous epithelial, squamous mesenchymal, and adenocarcinoma, using prospectively collected institutional (n = 67) and publicly available (n = 304) data sets. Patients with tumors of the squamous mesenchymal subtype showed inferior survival outcomes compared with the other 2 molecular groups. High mesenchymal gene expression in cervical cancer cells positively correlated with the capacity to form spheroids and with resistance to radiation. CaSki organoids were radiation-resistant but sensitive to the glycolysis inhibitor, 2-DG. These experiments provide a strategy for response prediction by integrating large data sets, and highlight the potential for metabolic therapy to influence EMT phenotypes in cervical cancer.

Glutaminase Inhibitors Induce Thiol-Mediated Oxidative Stress and Radiosensitization in Treatment-Resistant Cervical Cancers

The purpose of this study was to determine if radiation (RT)-resistant cervical cancers are dependent upon glutamine metabolism driven by activation of the PI3K pathway and test whether PI3K pathway mutation predicts radiosensitization by inhibition of glutamine metabolism. Cervical cancer cell lines with and without PI3K pathway mutations, including SiHa and SiHa PTEN^-/- cells engineered by CRISPR/Cas9, were used for mechanistic studies performed in vitro in the presence and absence of glutamine starvation and the glutaminase inhibitor, telaglenastat (CB-839). These studies included cell survival, proliferation, quantification of oxidative stress parameters, metabolic tracing with stable isotope-labeled substrates, metabolic rescue, and combination studies with L-buthionine sulfoximine (BSO), auranofin (AUR), and RT. In vivo studies of telaglenastat ± RT were performed using CaSki and SiHa xenografts grown in immune-compromised mice. PI3K-activated cervical cancer cells were selectively sensitive to glutamine deprivation through a mechanism that included thiol-mediated oxidative stress. Telaglenastat treatment decreased total glutathione pools, increased the percent glutathione disulfide, and caused clonogenic cell killing that was reversed by treatment with the thiol antioxidant, N-acetylcysteine. Telaglenastat also sensitized cells to killing by glutathione depletion with BSO, thioredoxin reductase inhibition with AUR, and RT. Glutamine-dependent PI3K-activated cervical cancer xenografts were sensitive to telaglenastat monotherapy, and telaglenastat selectively radiosensitized cervical cancer cells in vitro and in vivo These novel preclinical data support the utility of telaglenastat for glutamine-dependent radioresistant cervical cancers and demonstrate that PI3K pathway mutations may be used as a predictive biomarker for telaglenastat sensitivity.

Alteration of Cellular Reduction Potential Will Change 64Cu-ATSM Signal With or Without Hypoxia

Therapies targeting reductive/oxidative (redox) metabolism hold potential in cancers resistant to chemotherapy and radiation. A redox imaging marker would help identify cancers susceptible to redox-directed therapies. Copper(II)-diacetyl-bis(4-methylthiosemicarbazonato) (Cu-ATSM) is a PET tracer developed for hypoxia imaging that could potentially be used for this purpose. We aimed to demonstrate that Cu-ATSM signal is dependent on cellular redox state, irrespective of hypoxia. Methods: We investigated the relationship between ⁶⁴Cu-ATSM signal and redox state in human cervical and colon cancer cells. We altered redox state using drug strategies and single-gene mutations in isocitrate dehydrogenases (IDH1/2). Concentrations of reducing molecules were determined by spectrophotometry and liquid chromatography-mass spectrometry and compared with ⁶⁴Cu-ATSM signal in vitro. Mouse models of cervical cancer were used to evaluate the relationship between ⁶⁴Cu-ATSM signal and levels of reducing molecules in vivo, as well as to evaluate the change in ⁶⁴Cu-ATSM signal after redox-active drug treatment. Results: A correlation exists between baseline ⁶⁴Cu-ATSM signal and cellular concentration of glutathione, nicotinamide adenine dinucleotide phosphate (NADPH), and nicotinamide adenine dinucleotide (NADH). Altering NADH and NADPH metabolism using drug strategies and IDH1 mutations resulted in significant changes in ⁶⁴Cu-ATSM signal under normoxic conditions. Hypoxia likewise changed ⁶⁴Cu-ATSM signal, but treatment of hypoxic cells with redox-active drugs resulted in a more dramatic change than hypoxia alone. A significant difference in NADPH was seen between cervical tumor orthotopic implants in vivo, without a corresponding difference in ⁶⁴Cu-ATSM signal. After treatment with β-lapachone, there was a change in ⁶⁴Cu-ATSM signal in xenograft tumors smaller than 50 mg but not in larger tumors. Conclusion: ⁶⁴Cu-ATSM signal reflects redox state, and altering redox state impacts ⁶⁴Cu-ATSM metabolism. Our animal data suggest there are other modulating factors in vivo. These findings have implications for the use of ⁶⁴Cu-ATSM as a predictive marker for redox therapies, though further in vivo work is needed.

Abstract 5463: Free fatty acids augment radiation-induced cytotoxicity in cervical cancer cells via mTOR/Akt//PPARg/p53-mediated pathway

Purposes of the study: Our clinical results show that obese patients with cervical cancer who are treated with definitive chemoradiation have favorable outcomes, and this effect is independent of diabetes or metformin use. PI3K/AKT pathway signaling is decreased in cervical tumors from obese hosts, even in the context of genomic mutations that would otherwise activate PI3K signaling, such as PTEN deletion. The objective of the present study is to determine whether other factors related to obesity, such as circulating free fatty acids, influence radiation responses in vitro.

Experimental procedures: Radiation sensitivity experiments were performed in cervical cancer cells with and without PI3K pathway mutations (CaSki (mutant), ME180 (mutant), SiHa (WT). To determine whether combination treatment of free fatty acids (palmitic, oleic and linoleic) plus radiation increases cytotoxicity in cervical cells, we performed cell viability assay, long term colony formation assays (CFA) and morphological examination by vertical microscope. To determine whether the addition of free fatty acids to radiation influences cell survival signaling, a series of Western blots were performed.

Summary: We observed that combination treatment of free fatty acids and radiation significantly increased cytotoxicity in all the cervical cancer cell lines tested. Mechanistic investigations revealed that free fatty acids induced potentiation of radiation-induced cytotoxicity through downregulation of p-mTOR, p-Akt and PTEN. Furthermore, we observed that this combination regimen upregulates the expression PPARγ and p53.

Conclusions: Free fatty acids potentiated the effect of radiation in PI3K-activated cervical cancer cell lines through mTOR/Akt//PPARg/p53 mediated pathway. Future studies will characterize the mechanism of free fatty acid potentiation of radiation-induced tumor cell death in detail, including the potential contribution of lipid peroxidation and alterations in glucose metabolism.

Citation Format: Naoshad Muhammad, Ramachandran Rashmi, Fiona Ruiz, Michael C. Zahner, Julie K. Schwarz. Free fatty acids augment radiation-induced cytotoxicity in cervical cancer cells via mTOR/Akt//PPARg/p53-mediated pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5463.

Radioresistant Cervical Cancers Are Sensitive to Inhibition of Glycolysis and Redox Metabolism

Highly glycolytic cervical cancers largely resist treatment by cisplatin and coadministered pelvic irradiation as the present standard of care. In this study, we investigated the effects of inhibiting glycolysis and thiol redox metabolism to evaluate them as alternate treatment strategies in these cancers. In a panel of multiple cervical cancer cell lines, we evaluated sensitivity to inhibition of glycolysis (2-deoxyglucose, 2-DG) with or without simultaneous inhibition of glutathione and thioredoxin metabolism (BSO/AUR). Intracellular levels of total and oxidized glutathione, thioredoxin reductase activity, and indirect measures of intracellular reactive oxygen species were compared before and after treatment. Highly radioresistant cells were the most sensitive to 2-DG, whereas intermediate radioresistant cells were sensitive to 2-DG plus BSO/AUR. In response to 2-DG/BSO/AUR treatment, we observed increased levels of intracellular oxidized glutathione, redox-sensitive dye oxidation, and decreased glucose utilization via multiple metabolic pathways including the tricarboxylic acid cycle. 2-DG/BSO/AUR treatment delayed the growth of tumors composed of intermediate radioresistant cells and effectively radiosensitized these tumors at clinically relevant radiation doses both in vitro and in vivo Overall, our results support inhibition of glycolysis and intracellular redox metabolism as an effective alternative drug strategy for the treatment of highly glycolytic and radioresistant cervical cancers.Significance: This study suggests a simple metabolic approach to strike at an apparent Achilles' heel in highly glycolytic, radioresistant forms of cervical cancers, possibly with broader applications in cancer therapy. Cancer Res; 78(6); 1392-403. ©2018 AACR.

Giant Occipital Intradiploic Epidermoid Cyst

Intraparenchymal or intradiploic epidermoid cysts are very rare. Most of these cysts, when present, tend to involve the frontal and temporal lobes, and occasionally, the pineal gland or the brain stem. Here, we report a 45-year-old female, who presented with localized occipital headache and a tender occipital swelling, gradually increasing in size. She was hemodynamically and neurologically stable and did not have any focal neurological deficits. Whole skull and brain imaging revealed a well-demarcated expansile lytic lesion in the right occipital bone, which was hypointense on T1-weighted and hyperintense on both T2-weighted imaging and diffusion-weighted imaging without any contrast enhancement. The patient underwent a right occipital craniotomy and total excision of the intradiploic space occupying lesion. Histopathological examination confirmed the lytic bone lesion over occipital bone as intradiploic epidermoid cyst.

Clinical outcomes and differential effects of PI3K pathway mutation in obese versus non-obese patients with cervical cancer

The purpose of this study was to evaluate the effect of obesity and obesity-associated factors on the outcomes of patients with cervical cancer. Outcomes were evaluated in 591 patients with FIGO Ib to IV cervical cancer treated uniformly with definitive radiation. Patients were stratified into 3 groups based upon pretreatment Body Mass Index (BMI): A ≤ 18.5; B 18.6 – 34.9; and C ≥ 35. The 5-year freedom from failure rates were 58, 59, and 73% for BMI groups A, B, and C (p = 0.01). Overall survival rates were 50, 59, and 68%, respectively (p = 0.02). High expression of phosphorylated AKT (pAKT) was associated with poor outcomes only in non-obese patients. Obese patients with PI3K pathway mutant tumors had a trend toward favorable outcomes, while a similar effect was not observed in non-obese patients. Compared to similar tumors from non-obese hosts, PIK3CA and PTEN mutant tumors from obese patients failed to express high levels of phosphorylated AKT and its downstream targets. These results show that patients with obesity at the time of diagnosis of cervical cancer exhibit improved outcomes after radiation. PI3K/AKT pathway mutations are common in obese patients, but are not associated with activation of AKT signaling.

Correlation of Audio-Visual Reaction Time with Body Mass Index & Skin Fold Thickness Between Runners and Healthy Controls

Audio-visual reaction time is essential for activities like driving and very important in sports persons. Reaction time of 31 National level runners was compared with 31 controls. Runners were subdivided into two groups, group A (>2 yrs & < 3 yrs of training) and group B (>3 yrs & < 10 yrs of training). Correlation between Body Mass Index & Skin Fold Thickness with reaction time was also analyzed. Reaction time was significantly less in runners (p<0.05) when compared to controls and also in group B. Correlation analysis has shown negative correlation of BMI with reaction time with statistically significant value for green color in runners. Skin Fold Thickness also showed a negative correlation with reaction time but was not statistically significant. Improvement in reaction time by regular practice will ultimately improve sports person’s performance.

Development of sandwich dot-ELISA for specific detection of Ochratoxin A and its application on to contaminated cereal grains originating from India

In the present study, generation and characterization of a highly specific monoclonal antibody (mAb) against Ochratoxin A (OTA) was undertaken. The generated mAb was further used to develop a simple, fast, and sensitive sandwich dot-ELISA (s-dot ELISA) method for detection of OTA from contaminated food grain samples. The limit of detection (LOD) of the developed enzyme-linked immunosorbent assay (ELISA) method was determined as 5.0 ng/mL of OTA. Developed method was more specific toward OTA and no cross reactivity was observed with the other tested mycotoxins such as deoxynivalenol, fumonisin B1, or aflatoxin B1. To assess the utility and reliability of the developed method, several field samples of maize, wheat and rice (n = 195) collected from different geographical regions of southern Karnataka region of India were evaluated for the OTA occurrence. Seventy two out of 195 samples (19 maize, 38 wheat, and 15 rice) were found to be contaminated by OTA by s-dot ELISA. The assay results were further co-evaluated with conventional analytical high-performance liquid chromatography (HPLC) method. Results of the s-dot ELISA are in concordance with HPLC except for three samples that were negative for OTA presence by s-dot ELISA but found positive by HPLC. Although positive by HPLC, the amount of OTA in the three samples was found to be lesser than the accepted levels (>5 μg/kg) of OTA presence in cereals. Therefore, in conclusion, the developed s-dot ELISA is a better alternative for routine cereal based food and feed analysis in diagnostic labs to check the presence of OTA over existing conventional culture based, tedious analytical methods.

Evaluation of a multiplex PCR assay for concurrent detection of four major mycotoxigenic fungi from foods

AIM

To develop and evaluate a multiplex polymerase chain reaction assay (mPCR) for the concurrent detection of four major mycotoxin metabolic pathway genes, viz. nor1 (aflatoxin), Tri6 (trichothecene), FUM13 (fumonisin) and otanps (ochratoxin A).

METHODS AND RESULTS

A mPCR assay with competitive internal amplification control, employing specific primers for each of the aforementioned four genes, was optimized and validated using 10 reference strains and 60 pure culture isolates. The standardized mPCR assay detected all four mycotoxin metabolic genes in artificially contaminated maize samples with a sensitivity of 2 × 10(3) CFU g(-1) for nor1-positive Aspergillus strains, Tri6 and FUM13-positive Fusarium strains and 2 × 10(4) CFU g(-1) for otanps-positive Penicillium strains. When the developed mPCR assay was applied to 40 natural foods, 35% (14 of 40) of the samples were contaminated with either one or more mycotoxins. The mPCR results were further evaluated with high-performance liquid chromatography (HPLC), and in general, both the methods provided unequivocal results.

CONCLUSION

The current mPCR assay is a rapid and reliable tool for simultaneous specific and sensitive detection of aflatoxigenic Aspergillus strains, trichothecene- and fumonisin-producing Fusarium strains, and ochratoxigenic Penicillium species from naturally contaminated foods.

SIGNIFICANCE AND IMPACT OF THE STUDY

This mPCR assay could be a supplementary strategy to current conventional mycotoxin analytical techniques such as thin-layer chromatography (TLC), high performance thin layer chromatography, HPLC, etc., and a reliable tool for high-throughput monitoring of major mycotoxin-producing fungi during the processing steps of food and feed commodities.

Enhanced ferritin/iron ratio in psoriasis

BACKGROUND & OBJECTIVES

Psoriasis is a chronic, recurrent skin disorder, with a poorly understood pathogenesis. Studies at molecular/genetic levels continue to explore various biomolecules as potential markers of the disease. In the present study, we sought to evaluate the possible roles of ferritin and iron in psoriasis.

METHODS

Patients with psoriasis (n=81) and healthy controls (n=45) were included. Patients were graded as mild, moderate and severe based on the Psoriasis Area Severity Index (PASI). Serum ferritin and iron levels were measured by electro chemiluminescence and inductively coupled plasma - atomic emission spectrometry (ICP-AES), respectively.

RESULTS

The ferritin levels in psoriasis patients were not significantly different from that of controls. There was no significant difference in ferritin concentrations between psoriasis groups of severity. Fe was found to be significantly reduced (P<0.05) in the psoriasis patients when compared to controls. The ferritin to Fe ratio was significantly higher (P<0.05) in the psoriasis groups when compared to the control group.

INTERPRETATION & CONCLUSIONS

Our results indicate a possible role of ferritin and iron in psoriasis. Further studies with large samples need to be done to confirm findings.

Abstract 2279: Akt inhibitor SC-66 leads to inhibition of mTOR pathway in cervical cancer cell line C33A

Background We observed previously that overexpression of activated Akt is associated with poor prognosis in cervical cancer patients treated with concurrent cisplatin and pelvic irradiation (communicated). Several inhibitors of the PI3K/Akt/mTOR pathway have been developed, and many are being tested in clinical trials. The purpose of this study was to test the allosteric Akt inhibitor, SC-66 in cervical cancer cell lines and to determine drug sensitivity and inhibition of downstream pathway components. Experimental Design Eight cervical cancer cell lines (CaSki, C33A, C41, HeLa, HT-3, ME-180, SiHa and SW756) were assessed for activation status of Akt (Ser473, Thr308 and Thr450), downstream targets of Akt (FOXO-1, GSK3-α, PRAS40) and mTOR (mTOR, ribosomal S6 kinases (p70S6K), (eukaryotic initiation factor 4E)-binding protein, 4E-BP1 and S6) pathway by western blot. Among these cell lines tested, one with high Akt (C33A) was chosen for further experiments. Cell lines were treated with the allosteric Akt inhibitor SC-66, which interferes with PH domain binding to PIP3 leading to Akt ubiquitination. The dose and time course analysis were done by determining the cell viability using Alamar Blue and EC50 using PRIZM software. Akt and mTOR pathway inhibition were assessed by analyzing phosphorylation of various molecules of the pathway with or without SC-66 (6-10µg/ml) by western blot. Results Expression of activated Akt (S473, T450 and T308) was prominent in C33A. Since C33A expressed high pAkt levels we checked for alterations in the upstream regulators PIK3CA and PTEN (Phosphatase and tensin homolog). C33A harboured G263A (R88Q) alteration in exon1 of PIK3CA and PTEN protein expression was undetected. C33A was found to be the most sensitive cell line towards SC-66 treatment, with an EC50 value of 0.486µg/ml followed by ME-180 (0.82µg/ml), SW756 (1µg/ml) and SiHa (2.5µg/ml). To test the effects of SC-66 on the Akt/mTOR pathway, C33A cells were treated with doses from 6-10µg/ml of SC-66 for 3h and all the mTOR pathway targets were inhibited effectively at 7µg/ml, and Akt substrates between 7-8µg/ml. Akt activates mTOR which in turn phosphorylates p70S6K and 4E-BP1 ultimately resulting in cell growth and proliferation. SC-66 is effective in blocking essentially all these steps of signaling in C33A, a cell line with high activated Akt. Conclusions SC-66 potently inhibits proliferation of cervical cancer cell lines. C33A, a cervical cancer cell line with high levels of pAkt, is highly sensitive to SC-66, resulted in inhibition of phosphorylation of mTOR, 4EBP1 and p70S6K. Since high levels of pAkt are associated with poor outcome after concurrent chemo-radiation in cervical cancer, SC-66 could prove to be an effective therapeutic adjunct in these patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2279. doi:1538-7445.AM2012-2279

Pathway-specific analysis of gene expression data identifies the PI3K/Akt pathway as a novel therapeutic target in cervical cancer

PURPOSE

Cervical tumor response on posttherapy 2[(18)F]fluoro-2-deoxy-d-glucose-positron emission tomography (FDG-PET) is predictive of survival outcome. The purpose of this study was to use gene expression profiling to identify pathways associated with tumor metabolic response.

EXPERIMENTAL DESIGN

This was a prospective tissue collection study for gene expression profiling of 62 pretreatment biopsies from patients with advanced cervical cancer. Patients were treated with definitive radiation. Fifty-three patients received concurrent chemotherapy. All patients underwent a pretreatment and a 3-month posttherapy FDG-PET/computed tomography (CT). Tumor RNA was harvested from fresh frozen tissue and hybridized to Affymetrix U133Plus2 GeneChips. Gene set enrichment analysis (GSEA) was used to identify signaling pathways associated with tumor metabolic response. Immunohistochemistry and in vitro FDG uptake assays were used to confirm our results.

RESULTS

There were 40 biopsies from patients with a complete metabolic response (PET-negative group) and 22 biopsies from patients with incomplete metabolic response (PET-positive group). The 3-year cause-specific survival estimates were 98% for the PET-negative group and 39% for the PET-positive group (P < 0.0001). GSEA identified alterations in expression of genes associated with the PI3K/Akt signaling pathway in patients with a positive follow-up PET. Immunohistochemistry using a tissue microarray of 174 pretreatment biopsies confirmed p-Akt as a biomarker for poor prognosis in cervical cancer. The phosphoinositide 3-kinase (PI3K) inhibitor LY294002 inhibited FDG uptake in vitro in cervical cancer cell lines.

CONCLUSIONS

Activation of the PI3K/Akt pathway is associated with incomplete metabolic response in cervical cancer. Targeted inhibition of PI3K/Akt may improve response to chemoradiation.

Overexpression of BH3-Only Protein BNIP3 Leads to Enhanced Tumor Growth

BCL-2/E1B-19 kDa-interacting protein 3 (BNIP3) is a BH3-only mitochondrial protein. Expression of BNIP3 is strongly stimulated by hypoxia. Up-regulation of BNIP3 has been detected in several human carcinomas including carcinomas of the lung and breast. The significance of BNIP3 overexpression in these cancers is not known. To determine whether BNIP3 plays a role in tumor growth, we generated A549 lung carcinoma cells that overexpressed BNIP3 and examined their ability to form tumors in the mouse xenograft model. All cell lines that overexpressed BNIP3 formed larger tumors compared to the parental or vector-transformed A549 cells. Breast carcinoma cell lines that overexpressed BNIP3 also induced tumors in athymic mice in the absence of hormone administration, while the parental cell line did not. Stable shRNA-mediated knockdown of endogenous BNIP3 severely impaired the tumorigenic activity of A549 cells. The tumor growth-enhancing activity was reduced by deletion of the BH3 domain of BNIP3. Expression of a dominant-negative mutant of BNIP3 lacking the C-terminal transmembrane domain also inhibited the tumorigenic potential of A549 cells. These results suggest that BNIP3 plays a fundamental role in the development of certain solid tumors such as the lung and breast carcinomas.

Flice inhibitory protein is associated with the survival of neonatal neutrophils

Neonatal polymorphonuclear leukocytes (PMN) exhibit delayed apoptosis both constitutively and under inflammatory conditions, and evidence has linked PMN longevity to the presence of antiapoptotic proteins. Activation of the survival-associated transcription factor, nuclear factor kappa B (NF-κB), promotes the synthesis of several antiapoptotic proteins including Flice inhibitory protein (FLIP). Neonatal and adult PMN were compared in this study to test the hypothesis that FLIP modulates age-related apoptosis. Expression of the short isoform, FLIP-S, was prominent at baseline and persisted during spontaneous apoptosis in neonatal PMN, whereas basal expression was lower and decreased under the same conditions in adult PMN. Stable FLIP-S expression in neonatal PMN was associated with a relative resistance to apoptosis in response to the protein synthesis inhibitor, cycloheximide (CHX), or the NF-κB inhibitor, gliotoxin. In contrast, similar treatment of adult PMN promoted greater overall apoptosis accompanied by FLIP degradation. Nuclear levels of phosphorylated p65, a critical NF-κB dimer, were relatively robust in neonatal PMN under basal conditions or after stimulation with TNF-α, a cytokine that induces FLIP. In conclusion, persistent FLIP-S expression is involved in the longevity of neonatal PMN, and our data suggest a contribution of NF-κB signaling and related survival mechanisms.

Quality of life in HIV/AIDS

Given the longevity achievable with current prophylactic and therapeutic strategies for persons with HIV infection, quality of life (QOL) has emerged as a significant medical outcome measure, and its enhancement has an important goal. This review highlights the relevance and complexity of physical, psychological, and social factors as determinants of health-related quality of life in HIV-infected persons. Existing data suggest that physical manifestations, antiretroviral therapy, psychological well-being, social support systems, coping strategies, spiritual well-being, and psychiatric comorbidities are important predictors of QOL in this population. Consequently, the impact of HIV infection on the dimensions of QOL, including physical and emotional well-being, social support systems, and life roles, has emerged as a key issue for persons infected with HIV.

Quality of life in HIV/AIDS

Given the longevity achievable with current prophylactic and therapeutic strategies for persons with HIV infection, quality of life (QOL) has emerged as a significant medical outcome measure, and its enhancement has an important goal. This review highlights the relevance and complexity of physical, psychological, and social factors as determinants of health-related quality of life in HIV-infected persons. Existing data suggest that physical manifestations, antiretroviral therapy, psychological well-being, social support systems, coping strategies, spiritual well-being, and psychiatric comorbidities are important predictors of QOL in this population. Consequently, the impact of HIV infection on the dimensions of QOL, including physical and emotional well-being, social support systems, and life roles, has emerged as a key issue for persons infected with HIV.

Diet in dermatology: present perspectives

Many nutrients are essential for life, and an adequate amount of nutrients in the diet is necessary for providing energy, building and maintaining body organs, and for various metabolic processes. The role of food in the induction of various skin disorders and skin diseases leading to nutritional deficiencies is well known. The photo-protective potential of antioxidants, the effects of micronutrient supplementation on the skin immune system, and the modulating effects of fatty acids on skin disorders are well documented. Skin diseases due to nutritional deficiencies, the dietary role in skin immunity and various skin diseases, and the role of antioxidants and other supplements in skin health have been reviewed.

Relevance of psychiatry in dermatology: Present concepts

Skin is an organ that has a primary function in tactile receptivity and reacts directly upon emotional stimuli. Dermatological practice involves a psychosomatic dimension. A relationship between psychological factors and skin diseases has long been hypothesized. Psychodermatology addresses the interaction between mind and skin. It is divided into three categories according to the relationship between skin diseases and mental disorders. This article reviews different dermatological conditions under each of the three categories namely psychosomatic disorders, dermatological conditions due to primary and secondary psychiatric disorders. Dermatological conditions resulting from psychiatric conditions like stress/depression and those caused by psychiatric disorders are discussed. This review intends to present the relationship between the 'skin' and the 'mind' specifically from the dermatology point of view. The effects on the quality of life as a result of psychodermatological conditions are highlighted. A multidisciplinary approach for treatment from both dermatologic and psychiatric viewpoints are suggested.

Siglec-9 and SHP-1 are differentially expressed in neonatal and adult neutrophils

Neonatal PMN (polymorphonuclear neutrophils) exhibit altered inflammatory responsiveness and greater longevity compared with adult PMN; however, the involved mechanisms are incompletely defined. Receptors containing immunoreceptor tyrosine-based inhibitory motif (ITIM) domains promote apoptosis by activating inhibitory phosphatases, such as Src homology domain 2-containing tyrosine phosphatase-1 (SHP-1), that block survival signals. Sialic acid-binding immunoglobulin-like lectin (Siglec)-9, an immune inhibitory receptor with an ITIM domain, has been shown to induce cell death in adult PMN in association with SHP-1. To test our hypothesis that neonatal PMN inflammatory function may be modulated by unique Siglec-9 and SHP-1 interactions, we compared expression of these proteins in adult and neonatal PMN. Neonatal PMN exhibited diminished cellular expression of Siglec-9, which was phosphorylated in the basal state. Granulocyte-macrophage colony-stimulating factor (GM-CSF) treatment decreased Siglec-9 phosphorylation levels in neonatal PMN but promoted its phosphorylation in adult PMN, observations associated with altered survival signaling. Although SHP-1 expression was also diminished in neonatal PMN, GM-CSF treatment had minimal effect on phosphorylation status. Further analysis revealed that Siglec-9 and SHP-1 physically interact, as has been observed in other immune cells. Our data suggest that age-specific interactions between Siglec-9 and SHP-1 may influence the altered inflammatory responsiveness and longevity of neonatal PMN.

A comprehensive review of biomarkers in psoriasis

Psoriasis is a common, chronic skin disorder, the pathogenesis of which is incompletely understood. Results from various clinical and experimental studies indicate that psoriasis is a complex, multifactorial disease with a genetic predisposition. Factors such as climate, physical trauma, drug, stress and infections (Streptococcus, human immunodeficiency virus) are known to trigger psoriasis. The success of treatment of psoriasis with T-cell depletion and antitumour necrosis factor (TNF)-alpha treatment is explained by the involvement of T cells and TNF- alpha in the pathogenesis of psoriasis. The biochemical basis for the pathogenesis of psoriasis can be attributed to both overexpression and underexpression of certain proteins in psoriatic lesions. The anomalies in protein expression can be classified as abnormal keratinocyte differentiation, keratinocyte hyperproliferation and inflammation. Oxidative stress (OS) and increased free-radical generation have been linked to skin inflammation in psoriasis. The review presents evidence for various markers of psoriasis that can be targeted for effective treatment, including biomarkers of inflammation, keratinocyte hyperproliferation and abnormal differentiation, and stress.

BH3-only protein BIK induces caspase-independent cell death with autophagic features in Bcl-2 null cells

The BH3-only protein BIK normally induces apoptotic cell death. Here, we have investigated the role of BCL-2 in BIK-induced cell death using Bcl-2+/+ and Bcl-2-/- mouse embryo fibroblasts. Ectopic expression of BIK in Bcl-2-/- cells resulted in enhanced cell death compared to Bcl-2+/+ cells. In these cells, while caspase-8 was activated, there was no significant activation of caspase-9 and 3. There was no detectable mitochondrial to cytosolic release of cytochrome-c. However, there was significant redistribution of AIF from mitochondria to the nucleus. The extent of BIK-induced cell death was augmented by treatment with the pancaspase inhibitor, zVAD-fmk. The Bcl-2 null cells expressing BIK exhibited autophagic features such as cytosolic vacuoles, punctate distribution of LC3 and enhanced expression of Beclin-1. The survival of BIK-expressing Bcl-2-/- cells was enhanced in the presence of PI3 kinase inhibitors 3-methyladenine and Wortmannin and also by depletion of Atg5 and Beclin-1. Death of BIK-expressing Bcl-2-/- cells treated with zVAD-fmk was increased under caspase-8 depletion. Our results suggest enhanced expression of BIK in the Bcl-2 deficient cells leads to cell death with autophagic features and the extent of such cell death could be increased by inhibition of caspases.

Caspase-2 triggers Bax-Bak-dependent and -independent cell death in colon cancer cells treated with resveratrol

Polyphenol phytoalexin (resveratrol), found in grapes and red wine is a strong chemopreventive agent with promising safety records with human consumption and unique forms of cell death induction in a variety of tumor cells. However, the mechanism of resveratrol-induced apoptosis upstream of mitochondria is still not defined. The results from this study suggest that caspase-2 activation occurs upstream of mitochondria in resveratrol-treated cells. The upstream activation of caspase-2 is not dependent on its antioxidant property or NF-kappaB inhibition. The activated caspase-2 triggers mitochondrial apoptotic events by inducing conformational changes in Bax/Bak with subsequent release of cytochrome c, apoptosis-inducing factor, and endonuclease G. Caspase-8 activation seems to be independent of these events and does not appear to be mediated by classical death receptor processing or downstream caspases. Both caspase-2 and caspase-8 contribute toward the mitochondrial translocation of Bid, since neither caspase-8 inhibition nor caspase-2 inhibition could prevent translocation of Bid DsRed into mitochondria. Caspase-2 inhibitors or antisense silencing of caspase-2 prevented cell death induced by resveratrol and partially prevented processing of downstream caspases, including caspase-9, caspase-3, and caspase-8. Studies using mouse embryonic fibroblasts deficient for both Bax and Bak indicate the contribution of both Bax and Bak in mediating cell death induced by resveratrol and the existence of Bax/Bak-independent cell death possibly through caspase-8- or caspase-2-mediated mitochondria-independent downstream caspase processing.

Induction of apoptosis by curcumin and its implications for cancer therapy

Curcumin (diferuloyl methane), the yellow pigment in turmeric (Curcuma longa), is a potent chemopreventive agent that inhibits proliferation of cancer cells by arresting them at various phases of the cell cycle depending upon the cell type. Curcumin-induced apoptosis mainly involves the mitochondria-mediated pathway in various cancer cells of different tissues of origin. In some cell types like thymocytes, curcumin induces apoptosis-like changes whereas in many other normal and primary cells curcumin is either inactive or inhibits proliferation, but does not appear to induce apoptosis. These together with reports that curcumin protects cells against apoptosis induced by other agents, underscore the need for further understanding of the multiple mechanisms of cell death unleashed by curcumin. Tumor cells often evade apoptosis by expressing several antiapoptotic proteins, down-regulation and mutation of proapoptotic genes and alterations in signaling pathways that give them survival advantage and thereby allow them to resist therapy-induced apoptosis. Many researchers including ourselves, have demonstrated the involvement of several pro and antiapoptotic molecules in curcumin-induced apoptosis, and ways to sensitize chemoresistant cancer cells to curcumin treatment. This review describes the mechanisms of curcumin-induced apoptosis currently known, and suggests several potential strategies that include down-regulation of antiapoptotic proteins by antisense oligonucleotides, use of proapoptotic peptides and combination therapy, and other novel approaches against chemoresistant tumors. Several factors including pharmacological safety, scope for improvement of structure and function of curcumin and its ability to attack multiple targets are in favor of curcumin being developed as a drug for prevention and therapy of various cancers.

Human colon cancer cells lacking Bax resist curcumin-induced apoptosis and Bax requirement is dispensable with ectopic expression of Smac or downregulation of Bcl-XL

Multiple apoptotic stimuli induce conformational changes in Bax, a proapoptotic protein from the Bcl-2 family and its deficiency is a frequent cause of chemoresistance in colon adenocarcinomas. Curcumin, a dietary compound from turmeric, is known to induce apoptosis in a variety of cancer cells. To understand the role of Bax in curcumin-induced apoptosis we used HCT116 human colon cancer cells with one allele of Bax gene (Bax+/-) and Bax knockout HCT116 (Bax-/-) cells in which Bax gene is inactivated by homologous recombination. Cell viability decreased in a concentration-dependent manner in Bax+/- cells treated with curcumin (0-50 microM) whereas only minimal changes in viability were observed in Bax-/- cells upon curcumin treatment. In Bax-/- cells curcumin-induced activation of caspases 9 and 3 was blocked and that of caspase 8 remained unaltered. Curcumin-induced release of cytochrome c, Second mitochondria derived activator of caspase (Smac) and apoptosis inducing factor (AIF) was also blocked in Bax-/- cells and reintroduction of Bax, downregulation of the antiapoptotic protein Bcl-XL by antisense DNA as well as the overexpression of Smac, highly sensitized the Bax-/- cells toward curcumin-induced apoptosis. There was no considerable difference in the percentage of apoptotic cells in Bak RNAi transfected Bax+/- or Bax-/- cells treated with curcumin when compared with their corresponding vector transfected cells treated with curcumin. The present study demonstrates the role of Bax but not Bak as a critical regulator of curcumin-induced apoptosis and implies the potential of targeting antiapoptotic proteins like Bcl-XL or overexpression of proapoptotic proteins like Smac as interventional approaches to deal with Bax-deficient chemo-resistant cancers for curcumin-based therapy.

Ectopic expression of Bcl-XL or Ku70 protects human colon cancer cells (SW480) against curcumin-induced apoptosis while their down-regulation potentiates it

Curcumin, the yellow pigment derived from Curcuma longa, is known to induce apoptosis of several cancer cells. However, many cancer cells protect themselves by over-expressing antiapoptotic proteins such as Bcl-XL or Ku70. To study their role in curcumin-induced apoptosis, human colon cancer cells (SW480) were made to over-express or under-express Bcl-XL (by stable transfection) and Ku70 (by transient transfection) using plasmid constructs that express their genes in sense or antisense orientation, respectively. Stable cells that express Bax [Bax-GFP (green fluorescent protein)], a proapoptotic member of the Bcl-2 family, were also established. Curcumin-induced cell death and nuclear condensation was more in AsBcl-XL and AsKu70 cells that under-express Bcl-XL and Ku70, respectively, compared with the vector-transfected cells. Bcl-XL and Ku70 protected the cells by inhibiting the release of cytochrome c, Smac (second mitochondria derived activator of caspase) and apoptosis inducing factor (AIF), and the activation of caspases 9, 8 and 3 triggered by curcumin. AsBcl-XL and AsKu70 cells were more sensitive to curcumin through enhanced activation of caspases 9 and 3 and release of cytochrome c, Smac and AIF. Curcumin-induced activation of caspase 8 was blocked by Ku70 but not by Bcl-XL. However, caspase 8 activation by curcumin was accelerated in both AsBcl-XL and AsKu70 cells suggesting a possible feedback activation of caspase 8 by caspase 3. Bax-GFP cells were highly sensitized when Ku70 was down-regulated supporting the reported role of Ku70 in the retention of Bax within the cytosol. The study reveals the potential of antisense inhibition of antiapoptotic proteins as an effective strategy to tackle chemoresistant cancers with curcumin.

Ectopic expression of Hsp70 confers resistance and silencing its expression sensitizes human colon cancer cells to curcumin-induced apoptosis

We have shown earlier that heat shock renders human colon cancer cells resistant to curcumin-induced apoptosis, but the contribution of individual heat shock proteins (hsps) to this resistance has not been tested. High expression of hsp27 and hsp70 in breast, endometrial and gastric cancers has been associated with metastasis, poor prognosis and resistance to chemo- or radiotherapy. In this study, SW480 cells were transfected with hsp70 cDNA in either the sense or antisense orientation and stable clones were selected and tested for their sensitivity to curcumin. The cells were protected from curcumin-induced cell death by hsp70 while cells harboring antisense hsp70 (Ashsp70) were highly sensitive to curcumin. Curcumin-induced nuclear condensation was less in hsp70 but more in Ashsp70 cells when compared with control vector-transfected cells. Loss of mitochondrial transmembrane potential induced by curcumin was further accelerated by antisense hsp70 expression and hsp70 restored it partly. Ashsp70 cells released more cytochrome c, AIF and Smac from mitochondria upon curcumin treatment than control cells. hsp70 partly prevented the release of AIF but not the other proteins. Activation of caspases 3 and 9 induced by curcumin was also inhibited by hsp70, whereas more activation could be seen in Ashsp70 cells, although caspase 8 activation was unaffected by changes in hsp70 expression. Curcumin-induced cleavage of PARP and DFF45 was inhibited by hsp70 but enhanced in Ashsp70 cells. The present study demonstrates the potential of hsp70 in protecting SW480 cells from curcumin-induced apoptosis and highlights that silencing the expression of hsp70 is an effective approach to augment curcumin-based therapy in cancers that are resistant due to hsp70 expression.

Human colon cancer cells differ in their sensitivity to curcumin-induced apoptosis and heat shock protects them by inhibiting the release of apoptosis-inducing factor and caspases

Mild heat treatment induced the expression of heat shock protein-70 (hsp70), hsp90 and hsp27 in two human colon cancer cell lines, one derived from primary tumor, SW480, and the other derived from the secondary lymph node tissue, SW620, of the same patient. SW620 cells appear to be more sensitive to curcumin-induced apoptosis. Heat shock protects both the human colon cancer cells from curcumin-induced apoptosis. Heat shock prevented, at least in part, the release of apoptosis inducing factor from mitochondria induced by curcumin although the release of second mitochondria derived activator of caspase and cytochrome c was unaffected in both the cells. Moreover, heat shock reduced curcumin-induced activation of caspases 9 and 3 but not 8.