A Novel RP-HPLC Method for Simultaneous Estimation of Vilanterol Trifenatate, Umeclidinium Bromide and Fluticasone Furoate in Inhalation Dry Powder Formulation.

The dry powder inhalation formulation containing vilanterol trifenatate, umeclidinium bromide and fluticasone furoate intended for the therapy of bronchospasm related to chronic obstructive pulmonary disease and bronchial asthma was selected for the development and validation of a novel, selective, accurate, precise, quick and cost-efficient reversed-phase, high-performance liquid chromatography method. Neither an official monograph nor a single method has yet been published for the simultaneous estimation of these three compounds, which makes this method novel. The stationary phase of an ACE-C18-PFP column (250 mm × 4.6 mm, 5 µ) was used with a mobile phase of 25-mM sodium perchlorate buffer (pH 2.5 adjusted with ortho-phosphoric acid) and acetonitrile (40:60% v/v) at a flow rate of 1 mL/min to optimize chromatographic variables. The column temperature was kept at 40°C, and detection was at 224 nm, which was the isosbestic point of these three drugs. Well-resolved good peak symmetry was obtained for all three molecules by isocratic elution in less than 10 min, and the retention times of vilanterol trifenatate, umeclidinium bromide and fluticasone furoate were found to be 3.7, 5.4 and 8.3 min, respectively. The proposed method was validated as per ICH Q2 (R1) guidelines, and the calibration curves were linear in concentration ranges of 5-35 µg/mL for vilanterol trifenatate, 5-80 µg/mL for umeclidinium bromide and 5-150 µg/mL for fluticasone furoate, with mean % recoveries of 99-100%. The limits of detection and quantitation are 0.15 and 0.45 µg/mL for vilanterol trifenatate, 0.58 and 1.77 µg/mL for umeclidinium bromide and 0.32 and 0.96 µg/mL for fluticasone furoate, respectively. Hence, the proposed RP-HPLC technique was successfully used to quantify the inhalation formulation containing all three compounds.

Mobile Phones: Vital Addiction or Lethal Addiction? Mobile Phone Usage Patterns and Assessment of Mobile Addiction among Undergraduate Medical Students in Telangana, India.

BACKGROUND: Increased mobile phone usage among undergraduate medical students causes a detrimental effect on their health. The main focus of this study is to determine the pattern of mobile phone usage among undergraduate medical students in Hyderabad, India, and the detrimental effect on their health due to excess mobile use. MATERIALS AND METHODS: A cross-sectional study was conducted among undergraduate medical students from various medical colleges in Hyderabad, India, from September 2020 to January 2021. Data were collected from 626 respondents using a semistructured, pretested questionnaire. Smartphone Addiction Scale-Short Version (SAS-SV) was used to assess the risk of smartphone addiction. Microsoft Excel and SAS were employed to analyze the data. Associations were examined using Fisher's exact test. RESULTS: 100% of the respondents were using mobiles, with 83.2% spending more than 4 hours on them. Only 22% reported that no mobile use during classes. Half (51.6%) admitted to keeping their mobiles close by while sleeping. 84.3% used social networking apps via their mobiles. Common symptoms arising from prolonged mobile usage included eye strain (67.9%), blurred vision (31.4%), and numbness or tingling in palms (30.9%). 52.70% of the respondents were at high risk of mobile addiction according to SAS-SV. Screen time more than 4 hours was associated with high risk of mobile addiction (p < 0.0001). Significant association was found between high risk of mobile addiction and eye strain (p < 0.0001), blurry vision (p=0.0115), numbness/tingling in palms (p < 0.0001), and heat/tingling in the auditory area (p < 0.0001). CONCLUSION: The study shows the alarming rate of risk of smartphone addiction among medical students. Students can be encouraged to assess their mobile addiction status and become aware of the issue. More research may be performed to develop standardized tools for early identification of mobile addiction and appropriate therapies for its rectification.

Adaptations and Safety Modifications to Perform Safe Minimal Access Surgery (MIS: Laparoscopy and Robotic) During the COVID-19 Pandemic: Practice Modifications Expert Panel Consensus Guidelines from Academia of Minimal Access Surgical Oncology (AMASO).

The pandemic of COVID-19 across the globe triggered national lockdowns hampering normal working for all the essential services including healthcare. In order to reduce transmission and safety of patients and healthcare workers, the elective surgeries have been differed. The visits to the hospitals for follow-ups and consultations received temporary halt. However, we cannot halt the treatment for cancer patients who may or may not be COVID-19 positives. These are emergencies and should be treated ASAP. Conducting emergency surgeries during pandemic like COVID-19 is challenge for surgeons and the entire hospital infrastructure. The available information about COVID-19 and its propensity of contamination through droplets and aerosol need some modifications for conducting surgeries successfully without contaminating the hospital buildings, protecting healthcare teams and the patient. With these objectives, some modifications in the operating theater including surgical techniques for minimal access, laparoscopy, and robotic surgery are proposed in this review article. This review article also discusses the safety measures to be followed for the suspected or confirmed COVID-19 patient and the guidelines and recommendations for healthcare teams while treating these patients. Although there is little evidence of viral transmission through laparoscopic or open approaches, modifications to surgical practice such as the use of safe smoke evacuation and minimizing energy device used to reduce the risk of exposure to aerosolized particles to healthcare team are proposed in this review article.

Correlation of Primary Tumour Size and Central Compartment Lymph Nodes Metastasis in Well Differentiated Thyroid Malignancies in a Tertiary Care Centre.

Central compartment lymph nodes are the first to be involved in thyroid carcinoma and associated with higher chances of recurrence. (1) Recurrence and revision surgery can be associated with a high risk of vocal cord paralysis and hypocalcemia. (2) However, the need for central compartment lymph nodes dissection routinely in all cases of thyroid malignancies is controversial considering the risk to recurrent laryngeal nerve and parathyroids. (3) The aim of the study was to evaluate the incidence of central compartment lymph nodes metastasis in well differentiated thyroid malignancy and their correlation with size of the primary tumour along with incidence of postoperative hypocalcemia and recurrent laryngeal nerve injury after central compartment lymph node dissection. Observational study 30 patients diagnosed as well-differentiated thyroid carcinoma after fine needle aspiration cytology and planned for total thyroidectomy and central compartment lymph node dissection in the Department of ENT at a tertiary care hospital in Mysuru were studied. After surgery, histopathological examination (HPE) of thyroid and lymph node specimen was done. Postoperatively, all patients were evaluated for hypocalcemia and recurrent laryngeal nerve injury. The incidence of central compartment lymph node metastasis after HPE was 66.6%. 80% cases with tumor size ≤ 1 cm and 64% cases having tumor size > 1 cm showed central compartment lymph node involvement. Overall Incidence of transient Hypocalcaemia was 40%. No case of recurrent laryngeal nerve palsy was observed. In well-differentiated thyroid malignancies we found a high incidence of central compartment lymph node involvement which was even higher with primary tumour of smaller size (≤ 1 cm). We did not find any incidence of permanent hypocalcemia and recurrent laryngeal nerve injury. So based on our study we emphasize on elective central compartment lymph node clearance to avoid recurrence.

A dosimetric comparison between applicators used for brachytherapy in carcinoma cervix - A single-institute prospective study.

INTRODUCTION: Cervical cancer is the second most common cancer among Indian women. Radical radiotherapy with external beam radiation therapy (EBRT) and brachytherapy is the standard treatment for FIGO stage IB2 to IVA. An appropriate selection of brachytherapy applicator is needed according to the patient's anatomy. The two most commonly used applicators for intracavitary radiotherapy (ICR), Fletcher's and Henschke, have dosimetric differences which are not well studied with two-dimensional (2D)-based planning which is the most common method used for women with carcinoma cervix in India. The purpose of our study was to compare and evaluate the dosimetric differences between these two applicators, which would help in better selection of the applicator in cervical cancer patients. MATERIALS AND METHODS: This is a single-institute prospective study. Fifty patients randomly included in the study received EBRT and ICR by Ir192 HDR remote afterloading technique with computer-based 2D planning. Fletcher's and Henschke applicators were used alternately for first two fractions. RESULTS: The results of the study showed lower bladder and rectal doses with Fletcher's applicator and similar doses to point A for both applicators. However, point B doses are lower with Fletcher's applicator. CONCLUSION: Our results showed a favorable dosimetry with Fletcher's applicator in ICR of carcinoma cervix. The feasibility of placement is much better for Henschke but dosimetric advantages of Fletcher's encourage use of Fletcher's applicator for patients with favorable anatomy to reduce organs at risk doses but with the disadvantage of lower dose to point B.

Competition between anisometric and aliphatic entities: an unusual phase sequence with the induction of a phase in an n-alkane-liquid crystal binary system.

In this work, we demonstrate two important features that arise out of introducing a liquid-crystalline (LC) compound into the rotator phase matrix and the consequent competition between the anisometric segments of the LC moieties and the aliphatic units. First, we show that the change in the structural character of the mixed medium depends on which of the entities forms the minority concentration: in the case of this being the alkane, the two components of the binary system are nanophase segregated, whereas if the LC molecules are present in a small concentration, then the layered structure merely gets roughened without any segregation. The second and more significant result of the calorimetric and X-ray experiments, at low LC concentrations, is the induction of a rotator phase that leads to unusual phase sequence not reported hitherto. Possible scenarios for the molecular arrangement are discussed. A Landau model is also presented that explains some of the observed features.

Mitofusin 1 degradation is induced by a disruptor of mitochondrial calcium homeostasis, CGP37157: a role in apoptosis in prostate cancer cells.

Mitochondria constantly divide (mitochondrial fission) and fuse (mitochondrial fusion) in a normal cell. Disturbances in the balance between these two physiological processes may lead to cell dysfunction or to cell death. Induction of cell death is the prime goal of prostate cancer chemotherapy. Our previous study demonstrated that androgens increase the expression of a mitochondrial protein involved in fission and facilitate an apoptotic response to CGP37157 (CGP), an inhibitor of mitochondrial calcium efflux, in prostate cancer cells. However, the regulation and role of mitochondrial fusion proteins in the death of these cells have not been examined. Therefore, our objective was to investigate the effect of CGP on a key mitochondrial fusion protein, mitofusin 1 (Mfn1), and the role of Mfn1 in prostate cancer cell apoptosis. We used various prostate cancer cell lines and western blot analysis, qRT-PCR, siRNA, M30 apoptosis assay and immunoprecipitation techniques to determine mechanisms regulating Mfn1. Treatment of prostate cancer cells with CGP resulted in selective degradation of Mfn1. Mfn1 ubiquitination was detected following immunoprecipitation of overexpressed Myc-tagged Mfn1 protein from CGP-treated cells, and treatment with the proteasomal inhibitor lactacystin, as well as siRNA-mediated knockdown of the E3 ubiquitin ligase March5, protected Mfn1 from CGP-induced degradation. These data indicate the involvement of the ubiquitin-proteasome pathway in CGP-induced degradation of Mfn1. We also demonstrated that downregulation of Mfn1 by siRNA enhanced the apoptotic response of LNCaP cells to CGP, suggesting a likely pro-survival role for Mfn1 in these cells. Our results suggest that manipulation of mitofusins may provide a novel therapeutic advantage in treating prostate cancer.

Polarity-sensitive transient patterned state in a twisted nematic liquid crystal driven by very low frequency fields.

We report, for a rodlike nematic liquid crystal with small positive dielectric and conductivity anisotropies, and in the 90°-twisted configuration, low frequency (<2 Hz) square wave electric field generated Carr-Helfrich director modulation appearing transiently over a few seconds at each polarity reversal and vanishing almost completely under steady field conditions. Significantly, the instability is polarity sensitive, with the maximum distortion localized in the vicinity of the negative electrode, rather than in the midplane of the layer. This is revealed by the wave vector alternating in the two halves of the driving cycle between the alignment directions at the two substrates. Besides the Carr-Helfrich mechanism, quadrupolar flexoelectric polarization arising under electric field gradient is strongly indicated as being involved in the development of the transient periodic order. Similar transient instability is also observed in other nematic compounds with varying combinations of dielectric and conductivity anisotropies, showing its general nature. The study also deals with various characteristics of the electro-optic effect that emerge from the temporal variation of optical response for different driving voltages, frequencies, and temperatures.

Pharmacokinetic interaction of garlic and atorvastatin in dyslipidemic rats.

OBJECTIVE: To assess pharmacokinetic interaction of garlic with atorvastatin in dyslipidemic rats. MATERIALS AND METHODS: Sprague Dawley rats with induced dyslipidemia were divided into five groups of eight rats each. Group 1 was given atorvastatin (10 mg/kg body weight (b.wt) orally), group 2 was given atorvastatin (10 mg/kg b.wt orally)+garlic (1% w/w in feed), group 3 was maintained on atorvastatin (5 mg/kg b.wt orally)+garlic (0.5% w/w in feed), group 4 was maintained on atorvastatin (7.5 mg/kg b.wt orally)+garlic (0.25% w/w in feed), and group 5 was maintained on atorvastatin (2.5 mg/kg b.wt orally)+garlic (0.75% w/w in feed) for 12 weeks. Blood samples were collected at predetermined time intervals for kinetic analysis after the first and last oral dosing of atorvastatin for single and multiple dose studies, respectively. Plasma samples were assayed for atorvastatin concentration by High-Performance Liquid Chromatography (HPLC) and then the concentration-time data were analyzed. RESULTS: Maximum observed plasma concentration (C(max)), half-life, Area Under Plasma Concentration Time Curve (AUC), and Mean Resident Time (MRT) were significantly (P<0.05) increased during multiple dose kinetic study and elimination rate constant was significantly (P<0.05) decreased in comparison with their respective single-dose values, while there was no significant difference in time to achieve maximum concentration (t(max)) in all groups during both phases of the study. The highest values for kinetic parameters were observed in group 2 with correspondingly low activity of Cytochrome P(450) (CYP(450)). CONCLUSION: The study revealed higher values [C(max), AUC, Area Under The Moment Curve (AUMC), MRT, and half-life] of atorvastatin in garlic-treated groups.

Diltiazem enhances the apoptotic effects of proteasome inhibitors to induce prostate cancer cell death.

Diltiazem is a calcium channel blocker used to treat cardiovascular ailments. In addition, reports suggest that diltiazem induces cell death, which could make it a drug of choice for the treatment of cancer associated with hypertension. The goal of this research was to determine whether diltiazem is capable of inducing apoptosis in prostate cancer cells, either alone or in combination with the proteasome inhibitors, lactacystin and bortezomib (Velcade). Bortezomib is approved for the treatment of multiple myeloma; unfortunately, it has side effects that limit its utility. Presumably these side effects could be decreased by reducing its dose in combination with another drug. We have previously shown that lactacystin induces apoptosis in LNCaP cells; here, we show that this effect was enhanced by diltiazem. Furthermore, in proteasome inhibitor-resistant DU145 cells, diltiazem alone did not induce apoptosis but decreased cytosolic calcium levels and induced mitochondrial fission; likewise, lactacystin did not induce apoptosis but up-regulated the proapoptotic protein Bik. However, increasing concentrations of diltiazem in combination with lactacystin or bortezomib induced apoptosis in a dose-dependent and synergistic manner. The combination of diltiazem and lactacystin also up-regulated the levels of Bik and released Bak from Bcl-xL, indicating the involvement of the Bcl2 family pathway in this apoptosis. In addition, the drug combination up-regulated GRP78, suggesting also the involvement of endoplasmic reticulum stress in the apoptotic response. Thus, our results demonstrate a potential therapeutic advantage of combining a frequently used calcium channel blocker with proteasome inhibitors in the treatment of prostate cancer.

Novel role of androgens in mitochondrial fission and apoptosis.

Androgen and androgen receptors (AR) play critical roles in the proliferation of prostate cancer through transcriptional regulation of target genes. Here, we found that androgens upregulated the expression of dynamin-related protein 1 (Drp1), which is involved in the induction of mitochondrial fission, a common event in mitosis and apoptosis. Clinical tissue samples and various prostate cancer cell lines revealed a positive correlation between Drp1 and AR levels. Treatment of androgen-sensitive cells with an AR agonist, R1881, and antagonist, bicalutamide, showed that Drp1 is transcriptionally regulated by androgens, as confirmed by an AR ChIP-seq assay. Live imaging experiments using pAcGFP1-Mito stably transfected LNCaP (mito-green) cells revealed that androgen did not induce significant mitochondrial fission by itself, although Drp1 was upregulated. However, when treated with CGP37157 (CGP), an inhibitor of mitochondrial Ca²âº efflux, these cells exhibited mitochondrial fission, which was further enhanced by pretreatment with R1881, suggesting that androgen-induced Drp1 expression facilitated CGP-induced mitochondrial fission. This enhanced mitochondrial fission was correlated with increased apoptosis. Transfection with dominant-negative (DN-Drp1, K38A) rescued cells from increased apoptosis, confirming the role of androgen-induced Drp1 in the observed apoptosis with combination treatment. Furthermore, we found that CGP reduced the expression of Mfn1, a protein that promotes mitochondrial fusion, a process which opposes fission. We suggest that androgen-increased Drp1 enhanced mitochondrial fission leading to apoptosis. The present study shows a novel role for androgens in the regulation of mitochondrial morphology that could potentially be utilized in prostate cancer therapy.

Inhibition of PKCδ reduces cisplatin-induced nephrotoxicity without blocking chemotherapeutic efficacy in mouse models of cancer.

Cisplatin is a widely used cancer therapy drug that unfortunately has major side effects in normal tissues, notably nephrotoxicity in kidneys. Despite intensive research, the mechanism of cisplatin-induced nephrotoxicity remains unclear, and renoprotective approaches during cisplatin-based chemotherapy are lacking. Here we have identified PKCδ as a critical regulator of cisplatin nephrotoxicity, which can be effectively targeted for renoprotection during chemotherapy. We showed that early during cisplatin nephrotoxicity, Src interacted with, phosphorylated, and activated PKCδ in mouse kidney lysates. After activation, PKCδ regulated MAPKs, but not p53, to induce renal cell apoptosis. Thus, inhibition of PKCδ pharmacologically or genetically attenuated kidney cell apoptosis and tissue damage, preserving renal function during cisplatin treatment. Conversely, inhibition of PKCδ enhanced cisplatin-induced cell death in multiple cancer cell lines and, remarkably, enhanced the chemotherapeutic effects of cisplatin in several xenograft and syngeneic mouse tumor models while protecting kidneys from nephrotoxicity. Together these results demonstrate a role of PKCδ in cisplatin nephrotoxicity and support targeting PKCδ as an effective strategy for renoprotection during cisplatin-based cancer therapy.

Immunomodulatory effect of Moringa oleifera Lam. extract on cyclophosphamide induced toxicity in mice.

Immunomodulatory effect of ethanolic extract (50%) of M. oleifera leaves (MOE) has been studied in normal and immunosuppressed mice models. Different doses of MOE i.e. 125, 250 and 500 mg/kg body weight of mice were administered orally for 15 days. Cyclophosphamide at a dose of 30 mg/kg body weight was administered orally for the next 3 days. On day 16 and 19, hematological parameters like white blood cell (WBC) count, red blood cell (RBC) count, haemoglobin level (Hb), percent neutrophils and organ weight were recorded. Effect of MOE on phagocytic activity of mice macrophages was determined by carbon clearance test. MOE showed significant dose dependent increase in WBC, percent neutrophils, weight of thymus and spleen along with phagocytic index in normal and immunosuppressed mice. The results indicate that MOE significantly reduced cyclophosphamide induced immunosuppression by stimulating both cellular and humoral immunity.

A comprehensive study on the serum lipid profile and risk factor analysis for cardiovascular diseases in a cross-sectional Indian population.

Several epidemiological studies have established that Indians have a higher incidence of coronary heart disease. Because of vast differences in ethnicity, food habits and sociocultural background of Indians, it is essential that survey be conducted for profiling risk factor indicators in subjects from different parts of the country with adequate sample size. This study was carried out on CFTRI employees whose population is originally drawn from different parts of the country with diverse food habits. The population consisting of 624 subjects (514 men and 110 women) were subjected to general health check-up, blood and urine analysis under the supervision of a medical officer. Sixty-one individuals (9.77%) were found to be diabetic and 73 individuals (11.69%) were hypertensive of which 11.7% were also found to have diabetes. The mean serum cholesterol concentration in men was found to be 158 mg % and that in women was 165 mg %. Ratio of total cholesterol to HDL-cholesterol was found to be greater than 6.5 in all the cases. Blood group analysis indicated that 41.5% of the subjects belonged to O(+) group (n = 259) followed by B(+) 25.6% (n = 160), A(+) 24.6% (n = 154) and AB(+) 4.48% (n = 28). Twenty-three individuals were Rh-negative. It was observed that serum cholesterol and triglycerides were lower in O(+) groups, compared to individuals in other groups. The incidence of diabetes and hypertension in O(+) was 5.79% and 10.4%, B(+)12.5% and 15.6%, A(+) 11.0% and 12.3% and AB(+) 21.4% and 7.1% respectively. Eight individuals were found to have myocardial infarction. Among them four belonged to A(+), two to B(+) and one each to AB(+)and O(+).

Specific mitochondrial calcium overload induces mitochondrial fission in prostate cancer cells.

Mitochondria are structurally complex organelles that undergo fragmentation or fission in apoptotic cells. Mitochondrial fission requires the cytoplasmic dynamin-related protein, Drp1, which translocates to the mitochondria during apoptosis and interacts with the mitochondrial protein, Fis1. Finely tuned changes in cellular calcium modulate a variety of intracellular functions; in resting cells, the level of mitochondrial calcium is low, while it is higher during apoptosis. Mitochondria take up Ca(2+) via the Uniporter and extrude it to the cytoplasm through the mitochondrial Na+/Ca(2+) exchanger. Overload of Ca(2+) in the mitochondria leads to their damage, affecting cellular function and survival. The mitochondrial Na+/Ca2+ exchanger was blocked by benzodiazepine, CGP37157 (CGP) leading to increased mitochondrial calcium and enhancing the apoptotic effects of TRAIL, TNFalpha related apoptosis inducing ligand. In the present study, we observed that increasing mitochondrial calcium induced mitochondrial fragmentation, which correlated with the presence of Drp1 at the mitochondria in CGP treated cells. Under these conditions, we observed interactions between Drp1 and Fis1. The importance of Drp1 in fragmentation was confirmed by transfection of dominant negative Drp1 construct. However, fragmentation of the mitochondria was not sufficient to induce apoptosis, although it enhanced TRAIL-induced apoptosis. Furthermore, oligomerization of Bak was partially responsible for the increased apoptosis in cells treated with both CGP and TRAIL. Thus, our results show that combination of an apoptogenic agent and an appropriate calcium channel blocker provide therapeutic advantages.

Induction of apoptosis in renal tubular cells by histone deacetylase inhibitors, a family of anticancer agents.

Inhibitors of histone deacetylases, including suberoylanilide hydroxamic acid (SAHA) and Trichostatin A, are a new class of anticancer agents. With potent chemotherapy effects in cancers, these agents are not obviously toxic in normal nonmalignant cells or tissues. However, their toxicity in kidney cells has not been carefully evaluated. Here, we demonstrate a potent apoptosis-inducing activity of SAHA in cultured renal proximal tubular cells. SAHA induces apoptosis at low micromolar concentrations. At 5 muM, SAHA induces 30 to approximately 40% apoptosis in 18 h. The apoptosis is accompanied by notable caspase activation; however, the general caspase inhibitor VAD can only partially suppress SAHA-induced apoptosis, suggesting the involvement of both caspase-dependent and -independent mechanisms. SAHA treatment leads to cytochrome c release from mitochondria, which is suppressed by Bcl-2 but not by VAD. Bcl-2 consistently blocks SAHA-induced apoptosis. During SAHA treatment, Bcl-2 and Bcl-XL decrease, and Bid is proteolytically cleaved, whereas Bax and Bak expression remains constant. Bid cleavage, but not Bcl-2/Bcl-XL decrease, is completely suppressed by VAD. SAHA does not activate p53, and pifithrin-alpha (a pharmacological p53 inhibitor) does not attenuate SAHA-induced apoptosis, negating a role of p53 in SAHA-induced apoptosis. SAHA induces histone acetylation, which is not affected by VAD, Bcl-2, or pifithrin-alpha. Trichostatin A can also induce apoptosis and histone acetylation in renal tubular cells. Together, the results have shown evidence for renal toxicity of histone deacetylase inhibitors. The toxicity may be related to protein acetylation and decrease of antiapoptotic proteins including Bcl-2 and Bcl-XL.

Pectin induces apoptosis in human prostate cancer cells: correlation of apoptotic function with pectin structure.

Treatment options for androgen-independent prostate cancer cells are limited. Therefore, it is critical to identify agents that induce death of both androgen-responsive and androgen-insensitive cells. Here we demonstrate that a product of plant cell walls, pectin, is capable of inducing apoptosis in androgen-responsive (LNCaP) and androgen-independent (LNCaP C4-2) human prostate cancer cells. Commercially available fractionated pectin powder (FPP) induced apoptosis (approximately 40-fold above non-treated cells) in both cell lines as determined by the Apoptosense assay and activation of caspase-3 and its substrate, poly(ADP-ribose) polymerase. Conversely, citrus pectin (CP) and the pH-modified CP, PectaSol, had little or no apoptotic activity. Glycosyl residue composition and linkage analyses revealed no significant differences among the pectins. Mild base treatment to remove ester linkages destroyed FPP's apoptotic activity and yielded homogalacturonan (HG) oligosaccharides. The treatment of FPP with pectinmethylesterase to remove galacturonosyl carboxymethylesters and/or with endopolygalacturonase to cleave nonmethylesterified HG caused no major reduction in apoptotic activity, implicating the requirement for a base-sensitive linkage other than the carboxymethylester. Heat treatment of CP (HTCP) led to the induction of significant levels of apoptosis comparable to FPP, suggesting a means for generating apoptotic pectic structures. These results indicate that specific structural elements within pectin are responsible for the apoptotic activity, and that this structure can be generated, or enriched for, by heat treatment of CP. These findings provide the foundation for mechanistic studies of pectin apoptotic activity and a basis for the development of pectin-based pharmaceuticals, nutraceuticals, or recommended diet changes aimed at combating prostate cancer occurrence and progression.

Therapeutic advantage of combining calcium channel blockers and TRAIL in prostate cancer.

Disruption of intracellular calcium initiates multiple cell-damaging processes, such as apoptosis. In normal cells, the levels of Ca(2+) are low in the mitochondria, whereas in apoptotic cells, Ca(2+) increases. Mitochondria uptake Ca(2+) via an inner membrane channel called the uniporter and extrude it into the cytoplasm through a Na(+)/Ca(2+) exchanger. Overload of Ca(2+) in the mitochondria in CGP-treated cells leads to its damage, thus affecting cellular function and survival. The goal of these experiments was to determine the importance of mitochondrial calcium ([Ca(2+)](m)) in apoptosis of prostate cancer cells. Furthermore, we have examined the advantages of increasing the [Ca(2+)](m) and treating the cells with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a potent apoptotic agent. Our results show that, under these treatment conditions, inhibiting the Na(+)/Ca(2+) exchanger using benzothiazepin CGP-37157 (CGP) did not induce apoptosis. However, combination of CGP and TRAIL increased the apoptotic response approximately 25-fold compared with control. Increase in apoptosis followed enhanced levels of [Ca(2+)](m) and was accompanied by pronounced mitochondrial changes characteristic of mitochondria-mediated apoptosis. Experiments with calcium ionophores showed that mere increase in cytosolic and/or mitochondrial Ca(2+) was not sufficient to induce apoptosis. These results have therapeutic implications as inhibitors of Na(+)/Ca(2+) exchanger are being used for treating some neurologic and cardiologic ailments, and TRAIL induces apoptosis preferentially in cancer cells. Furthermore, this system provides an excellent model to investigate the role of [Ca(2+)](m) in apoptosis.

SAHA-sensitized prostate cancer cells to TNFalpha-related apoptosis-inducing ligand (TRAIL): mechanisms leading to synergistic apoptosis.

Treatment of cancer cells with histone deacetylase inhibitors (HDACi) such as suberolylanilide hydroxamic acid (SAHA) activates genes that promote apoptosis. To enhance proapoptotic efficiency, SAHA has been used in combination with radiation, kinase inhibitors and cytotoxic drugs. Although several prostate cells respond to TNFalpha-Related Apoptosis-Inducing Ligand (TRAIL), LNCaP are resistant. This model system was utilized to examine the advantages of combined treatment with SAHA and TRAIL. In LNCaP cells, TRAIL induced synergistic apoptosis when combined even with the lowest dose of SAHA. Treatment with caspase inhibitor confirmed that SAHA-induced apoptosis was mediated through caspases. In addition to induction of apoptosis, SAHA and TRAIL decreased the levels of proapoptotic proteins IKKalpha, IKKbeta and IKKgamma, suggesting that SAHA treatment may reduce the activity of NFkappaB. However, assay for NFkappaB luciferase reporter activity showed highly significant increase in SAHA-treated cells, supporting earlier suggestions that HDACi promotes NFkappaB transcriptional activity. Further analyses to determine the mechanisms by which the combination of SAHA and TRAIL led to synergistic apoptosis indicated that the apoptotic response of LNCaP is due to a complex regulation of death receptor pathway and alterations of NFkappaB activity at several regulatory steps.

Sensitization of TRAIL-resistant cells by inhibition of heat shock protein 90 with low-dose geldanamycin.

Due to its specificity and effectiveness, tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) is being tested for cancer therapy. Inhibition of the function of heat shock protein 90 (HSP90) is under clinical trials for cancer therapy. However, some cancer cells are resistant to TRAIL, and at the dose required for inducing apoptosis, geldanamycin, a drug that inhibits HSP90 function, has shown adverse effects. Therefore, our working plan was to identify a sublethal dose of geldanamycin and combine it with TRAIL to induce apoptosis in TRAIL-resistant prostate cancer cells. Treatment of LNCaP with 250 nmol/L geldanamycin inhibited HSP90 function but did not induce significant apoptosis. However, combination of geldanamycin and TRAIL induced highly significant apoptosis in TRAIL-resistant LNCaP cells. In addition to inducing caspase activity and apoptosis, treatment with geldanamycin and TRAIL decreased inhibitor of kappaB (IkappaB) kinase (IKK) complex proteins, IKKalpha, IKKbeta, and IKKgamma. The loss of IKK affected IkappaBalpha/nuclear factor-kappaB (NF-kappaB) interaction and reduced nuclear transport of NF-kappaB, resulting in reduced NF-kappaB activity. Our data show increase in apoptosis using low, suboptimal dose of geldanamycin when used with TRAIL. These results provide a means to alleviate two problems: resistance to TRAIL and adverse effects of high-dose geldanamycin.