Oncolytic adenovirus encoding LIGHT (TNFSF14) inhibits tumor growth via activating anti-tumor immune responses in 4T1 mouse mammary tumor model in immune competent syngeneic mice

LIGHT, also known as tumor-necrosis factor (TNF) superfamily member 14 (TNFSF14), is predominantly expressed on activated immune cells and some tumor cells. LIGHT is a pivotal regulator both for recruiting and activating immune cells in the tumor lesions. In this study, we armed human telomerase reverse transcriptase (TERT) promoter controlled oncolytic adenovirus with LIGHT to generate rAd.Light. rAd.Light effectively transduced both human and mouse breast tumor cell lines in vitro, and expressed LIGHT protein on the surface of tumor cells. Both rAd.Null, and rAd.Light could replicate in human breast cancer cells, and produced cytotoxicity to human and mouse mammary tumor cells. rAd.Light induced apoptosis resulting in tumor cell death. Using a subcutaneous model of 4T1 cells in BALB/c mice, rAd.Light was delivered intratumorally to evaluate the anti-tumor responses. Both rAd.Light and rAd.Null significantly inhibited the tumor growth, but rAd.Light produced much stronger anti-tumor effects. Histopathological analysis showed the infiltration of T lymphocytes in the tumor tissues. rAd.Light also induced stronger cellular apoptosis than rAd.Null in the tumors. Interestingly, on day 15, compared to rAd.Null, there was a significant reduction of Tregs following rAd.Light treatment. rAd.Light significantly increased Th1 cytokine interleukin (IL)-2 expression, and reduced Th2 cytokines expression, such as transforming growth factor β (TGF-β) and IL-10 in the tumors. These results suggest rAd.Light induced activation of anti-tumor immune responses. In conclusion, rAd.Light produced anti-tumor effect in a subcutaneous model of breast cancer via inducing tumor apoptosis and evoking strong anti-tumor immune responses. Therefore, rAd.Light has great promise to be developed as an effective therapeutic approach for the treatment of breast cancer.

LyP-1-Modified Oncolytic Adenoviruses Targeting Transforming Growth Factor β Inhibit Tumor Growth and Metastases and Augment Immune Checkpoint Inhibitor Therapy in Breast Cancer Mouse Models

We report here the development of oncolytic adenoviruses (Ads) that have reduced toxicity, enhanced tumor tropism, produce strong antitumor response, and can overcome resistance to immune checkpoint inhibitor therapy in breast cancer. We have shown that LyP-1 receptor (p32) is highly expressed on the surface of breast cancer cells and tumors from cancer patients, and that increased stromal expression of transforming growth factor β-1 (TGFβ-1) is associated with triple-negative breast cancer. Therefore, we constructed oncolytic Ads, AdLyp.sT and mHAdLyp.sT, in which the p32-binding LyP-1 peptide was genetically inserted into the adenoviral fiber protein. Both AdLyp.sT and mHAdLyp.sT express sTGFβRIIFc, a TGFβ decoy that can inhibit TGFβ pathways. mHAdLyp.sT is an Ad5/48 chimeric hexon virus in which hypervariable regions (HVRs 1-7) of Ad5 are replaced with the corresponding Ad48 HVRs. AdLyp.sT and mHAdLyp.sT exhibited better binding, replication, and produced higher sTGFβRIIFc protein levels in breast cancer cell lines compared with Ad.sT or mHAd.sT control viruses without LyP-1 peptide modification. Systemic delivery of mHAdLyp.sT in mice resulted in reduced hepatic/systemic toxicity compared with Ad.sT and AdLyp.sT. Intravenous delivery of AdLyp.sT and mHAdLyp.sT elicited a strong antitumor response in a human MDA-MB-231 bone metastasis model in mice, as indicated by bioluminescence imaging, radiographic tumor burden, serum TRACP 5b and calcium, and body weight analyses. Furthermore, intratumoral delivery of AdLyp.sT in 4T1 model in immunocompetent mice inhibited tumor growth and metastases, and augmented anti-PD-1 and anti-CTLA-4 therapy. Based on these studies, we believe that AdLyp.sT and mHAdLyp.sT can be developed as potential targeted immunotherapy agents for the treatment of breast cancer.

Oncolytic adenovirus targeting TGF-β enhances anti-tumor responses of mesothelin-targeted chimeric antigen receptor T cell therapy against breast cancer

Chimeric antigen receptor (CAR)-modified T cell therapy evokes only modest antitumor responses in solid tumors. Meso-CAR-T cells are CAR-T cells targeted mesothelin, which are over-expressed in tumor tissues of breast cancer patients. To improve the therapeutic effects, we combined it with rAd.sT, a transforming growth factor β signaling-targeted oncolytic adenovirus, to therapy breast cancer. In subcutaneous MDA-MB-231 xenograft of NSG mice, both rAd.sT and meso-CAR-T inhibited tumor growth, however combination therapy produced stronger inhibitory effects. Interestingly, rAd.sT reduced tumor burden at initial stage following vector treatments, while meso-CAR-T cells decreased tumor burden at a later stage. Moreover, meso-CAR-T could target tumor microenvironments, and combination therapy could enhance cytokines production, such as interleukin (IL)-6 and IL-12 in tumor microenvironment. In conclusion, combination of rAd.sT with meso-CAR-T produced much more impressive antitumor responses to breast cancer and its metastasis, which could be developed as a promising therapeutic strategy.

An Oncolytic Adenovirus Targeting Transforming Growth Factor β Inhibits Protumorigenic Signals and Produces Immune Activation: A Novel Approach to Enhance Anti-PD-1 and Anti-CTLA-4 Therapy

In an effort to develop a new therapy for cancer and to improve antiprogrammed death inhibitor-1 (anti-PD-1) and anticytotoxic T lymphocyte-associated protein (anti-CTLA-4) responses, we have created a telomerase reverse transcriptase promoter-regulated oncolytic adenovirus rAd.sT containing a soluble transforming growth factor receptor II fused with human IgG Fc fragment (sTGFβRIIFc) gene. Infection of breast and renal tumor cells with rAd.sT produced sTGFβRIIFc protein with dose-dependent cytotoxicity. In immunocompetent mouse 4T1 breast tumor model, intratumoral delivery of rAd.sT inhibited both tumor growth and lung metastases. rAd.sT downregulated the expression of several transforming growth factor β (TGFβ) target genes involved in tumor growth and metastases, inhibited Th2 cytokine expression, and induced Th1 cytokines and chemokines, and granzyme B and perforin expression. rAd.sT treatment also increased the percentage of CD8⁺ T lymphocytes, promoted the generation of CD4⁺ T memory cells, reduced regulatory T lymphocytes (Tregs), and reduced bone marrow-derived suppressor cells. Importantly, rAd.sT treatment increased the percentage of CD4⁺ T lymphocytes, and promoted differentiation and maturation of antigen-presenting dendritic cells in the spleen. In the immunocompetent mouse Renca renal tumor model, similar therapeutic effects and immune activation results were observed. In the 4T1 mammary tumor model, rAd.sT improved the inhibition of tumor growth and lung and liver metastases by anti-PD-1 and anti-CTLA-4 antibodies. Analysis of the human breast and kidney tumors showed that a significant number of tumor tissues expressed high levels of TGFβ and TGFβ-inducible genes. Therefore, rAd.sT could be a potential enhancer of anti-PD-1 and anti-CTLA-4 therapy for treating breast and kidney cancers.

Oncolytic Adenovirus rAd.DCN Inhibits Breast Tumor Growth and Lung Metastasis in an Immune-Competent Orthotopic Xenograft Model

The majority of advanced breast cancer patients develop distal metastasis, including lung and bone metastasis. However, effective therapeutic strategies to prevent metastasis are still lacking. Decorin is a natural inhibitor of transforming growth factor β, which plays a pivotal role in tumor metastasis. An oncolytic adenovirus expressing decorin, rAd.DCN, has been developed previously. In an immune-competent breast tumor (4T1) model, intratumoral (i.t.) as well as intravenous (i.v.) delivery of rAd.DCN inhibited growth of orthotopic tumors and spontaneous lung metastasis. It was shown that i.t. delivery of rAd.DCN produced higher levels of transgene expression and evoked stronger oncolysis of the tumors compared to i.v. delivery. However, i.v. delivery resulted in higher amount of virus accumulation in the lungs and produced stronger responses to prevent tumor lung metastasis. Oncolytic adenovirus-mediated decorin expression in the tumors downregulated the decorin target genes and decreased epithelial mesenchymal transition markers. Decorin expression in lung tissues also increased Th1 cytokine expression, such as interleukin (IL)-2, IL-12, and tumor necrosis factor α, and decreased Th2 cytokines, such as transforming growth factor β and IL-6. Moreover, rAd.DCN treatment induced strong systemic inflammatory responses and upregulated CD8⁺ T lymphocytes. In conclusion, rAd.DCN inhibits tumor growth and lung metastasis of breast cancer via regulating wnt/β-catenin, vascular endothelial growth factor (VEGF), and Met pathways, and modulating the antitumor inflammatory and immune responses. Considering that i.v. delivery was much more effective in preventing lung metastasis, systemic delivery of rAd.DCN might be a promising strategy to treat breast cancer lung metastasis.

Case Report: Unusual Radiation Risks in the Emergency Department –125I beads

The use of radioactive substances in medicine accounts for the largest radiation exposure to the population from non-natural sources worldwide. The use in healthcare confers many benefits, but inappropriate or unskilled use can result in health hazards and safety issues for both patients and healthcare workers. We present two cases of radiation safety issues related to patients presenting to our emergency department after receiving non-conventional brachytherapy in the form of radiation seeds being implanted in the abdominal wall. These were done for presumed treatment of metastatic cancer in another Asian country. We share our cases to all emergency department staff to heighten their alertness for potential exposure to radiation from patients with radionuclides.

Tunicamycin Enhances Neuroinvasion and Encephalitis in Mice Infected with Venezuelan Equine Encephalitis Virus

Venezuelan equine encephalitis (VEE) viruses cause natural outbreaks in humans and horses and represent a significant biothreat agent. The effect of tunicamycin on the course of the disease in mice with VEE was investigated, and the combined effects of these agents was characterized. CD-1 mice given 2.5 μg of tunicamycin had > 1,000-fold more virus in the brain 48 hours after infection with the virulent VEE strain V3000 and >100-fold of the attenuated strain V3034 at all tested times than did untreated mice, indicating enhanced neuroinvasion. Tunicamycin did not alter the viremia profiles of these viruses nor the replication of V3000 in the brain itself. Tunicamycin alone caused ultrastructural blood-brain barrier damage, yet neuroinvasion by V3000 in treated mice appeared to occur via the olfactory system rather than the blood-brain barrier. Tunicamycin-treated, V3000-infected mice also exhibited earlier and more severe weight loss, neurological signs, neuronal infection, neuronal necrosis and apoptosis, and inflammation than untreated, V3000-infected mice. The mean survival time of tunicamycin-treated, V3000-infected mice was 7.3 days versus 9.9 days for untreated, V3000-infected mice. These studies imply that animals that ingest toxins similar to tunicamycin, including the agent of annual ryegrass toxicity in livestock, are conceivably at greater risk from infections by encephalitis viruses and that humans and horses exposed to agents acting similar to tunicamycin may be more susceptible to encephalitis caused by VEE viruses. The exact mechanism of tunicamycin-enhanced neuroinvasion by VEE viruses requires further study.

Systemic Delivery of an Oncolytic Adenovirus Expressing Decorin for the Treatment of Breast Cancer Bone Metastases

The development of novel therapies for breast cancer bone metastasis is a major unmet medical need. Toward that end, we have constructed an oncolytic adenovirus, Ad.dcn, and a nonreplicating adenovirus, Ad(E1-).dcn, both containing the human decorin gene. Our in vitro studies showed that Ad.dcn produced high levels of viral replication and the decorin protein in the breast tumor cells. Ad(E1-).dcn-mediated decorin expression in MDA-MB-231 cells downregulated the expression of Met, β-catenin, and vascular endothelial growth factor A, all of which are recognized decorin targets and play pivotal roles in the progression of breast tumor growth and metastasis. Adenoviral-mediated decorin expression inhibited cell migration and induced mitochondrial autophagy in MDA-MB-231 cells. Mice bearing MDA-MB-231-luc skeletal metastases were systemically administered with the viral vectors, and skeletal tumor growth was monitored over time. The results of bioluminescence imaging and X-ray radiography indicated that Ad.dcn and Ad(E1-).dcn significantly inhibited the progression of bone metastases. At the terminal time point, histomorphometric analysis, micro-computed tomography, and bone destruction biomarkers showed that Ad.dcn and Ad(E1-).dcn reduced tumor burden and inhibited bone destruction. A nonreplicating adenovirus Ad(E1-).luc expressing the luciferase 2 gene had no significant effect on inhibiting bone metastases, and in several assays, Ad.dcn and Ad(E1-).dcn were better than Ad.luc, a replicating virus expressing the luciferase 2 gene. Our data suggest that adenoviral replication coupled with decorin expression could produce effective antitumor responses in a MDA-MB-231 bone metastasis model of breast cancer. Thus, Ad.dcn could potentially be developed as a candidate gene therapy vector for treating breast cancer bone metastases.

Abstract 723: Liver-detargeted Ad5/48 chimaeric hexon based oncolytic adenovirus targeting TGFβ signaling: A safe and effective approach for the treatment of prostate cancer bone metastases

Background: We have previously shown that systemic delivery of oncolytic Adenovirus 5 (Ad5) expressing soluble transforming growth factorβ receptorII-Fc protein (Ad.sTβRFc) produced anti-tumor responses in a mouse model of prostate cancer bone metastases. However, the majority of the Ad.sTβRFc was taken up by the liver causing hepatic and systemic toxicities. Since Ad5 uptake in the liver is primarily due to its binding with blood factor X (FX), and that Ad48 has much reduced binding with FX, to prevent the adenoviral-induced liver and systemic toxicity, a chimaeric Ad5/48 adenovirus mHAd.sTβRFc was created. Our objective is to examine the safety and efficacy of mHAd.sTβRFc in a mouse model of prostate cancer bone metastases.

Methods: Liver toxicity studies. Following intravenous delivery of adenoviruses, H&E staining of the liver tissues were performed to evaluate liver necrosis. Plasma liver alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured. Bone metastasis studies. PC3-luc2 cells were injected in left heart ventricle of nude mice. In mice bearing skeletal tumors, vectors were injected via tail vein. Bone metastases were examined by bioluminescence imaging (BLI) and X-ray radiography. Tumor burden was analyzed by H&E staining; osteoclasts were measured by tartarate resistant acid phosphatase staining, plasma calcium levels were determined, and microCT analyses of the bones were performed.

Results: Systemic delivery of Ad5 based Ad.sTβRFc showed that a low dose (2.5x1010 viral particles (VPs)/mouse or a high dose (1011 VPs/mouse ) produced significant liver necrosis and a transient increase in ALT and AST levels; the high dose (1011 VPs/mouse) killed all the mice by day 3. On the other hand, intravenous delivery of low or high dose of Ad5/48 chimaeric mHAd.sTβRFc virus did not produce liver damage or increased plasma ALT and AST levels; even the higher doses (up to 2x1011 VPs/mouse) did not cause any animal deaths. There was a much reduced liver uptake of mHAd.sTβRFc compared to Ad.sTβRFc. Intravenous delivery of Ad.sTβRFc and mHAd.sTβRFc (5x1010 viral particles (VPs)/mouse) exhibited a significant inhibition of bone metastases as revealed by BLI and X-ray analyses. The higher doses of mHAd.sTβRFc (2x1011 VPs/mouse or 4x1011 VPs/mouse) were more effective than the lower dose (5x1010 VPs/mouse) of Ad.sTβRFc or mHAd.sTβRFc in inhibiting bone metastases, and produced a significant reduction in the tumor burden, hypercalcemia and osteoclast numbers, and produced normal bone architect as revealed by the microCT scan analyses.

Conclusion: Ad5/48 chimaeric hexon based oncolytic adenoviruses produce much reduced liver and systemic toxicity, and can be administered in much larger amounts to produce superior anti-tumor responses, and should be tested in the future clinical trials in prostate cancer patients.

Citation Format: Weidong Xu, Zhenwei Zhang, Theresa Guise, Charles B. Brendler, Prem Seth. Liver-detargeted Ad5/48 chimaeric hexon based oncolytic adenovirus targeting TGFβ signaling: A safe and effective approach for the treatment of prostate cancer bone metastases. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 723. doi:10.1158/1538-7445.AM2014-723

Ad5/48 hexon oncolytic virus expressing sTGFβRIIFc produces reduced hepatic and systemic toxicities and inhibits prostate cancer bone metastases

We are interested in developing oncolytic adenoviruses for the treatment of prostate cancer (PCa) bone metastases. A key limitation of Adenovirus 5 (Ad5) is that upon systemic administration, it produces major liver and systemic toxicities. To address this issue, a chimaeric Ad5/48 adenovirus mHAd.sTβRFc was created. Seven hypervariable regions of Ad5 hexon present in Ad5-based Ad.sTβRFc expressing soluble transforming growth factor beta receptor II-Fc fusion protein (sTGβRIIFc), were replaced by those of Ad48. mHAd.sTβRFc, like Ad.sTβRFc, was replication competent in the human PCa cells, and produced high levels of sTGβRIIFc expression. Compared to Ad.sTβRFc, the systemic delivery of mHAd.sTβRFc in nude mice resulted in much reduced systemic toxicity, and reduced liver sequestration. Ad.sTβRFc produced significant liver necrosis, and increases in alanine transaminase, aspartate transaminase, lactate dehydrogenase, tumor necrosis factor-α, and interleukin-6 levels, while mHAd.sTβRFc produced much reduced responses of these markers. Intravenous delivery of Ad.sTβRFc or mHAd.sTβRFc (5 × 10(10) viral particles/mouse) in nude mice bearing PC-3-luc PCa bone metastases produced inhibition of bone metastases. Moreover, a larger dose of the mHAd.sTβRFc (4 × 10(11) viral particles /mouse) was also effective in inhibiting bone metastases. Thus, mHAd.sTβRFc could be developed for the treatment of PCa bone metastases.

Framework for constructing generic Jastrow correlation factors

We have developed a flexible framework for constructing Jastrow factors which allows for the introduction of terms involving arbitrary numbers of particles. The use of various three- and four-body Jastrow terms in quantum Monte Carlo calculations is investigated, including a four-body van der Waals-like term, and anisotropic terms. We have tested these Jastrow factors on one- and two-dimensional homogeneous electron gases, the Be, B, and O atoms, and the BeH, H2O, N2, and H2 molecules. Our optimized Jastrow factors retrieve more than 90% of the fixed-node diffusion Monte Carlo correlation energy in variational Monte Carlo for each system studied.

Intravenous administration of adenoviruses targeting transforming growth factor beta signaling inhibits established bone metastases in 4T1 mouse mammary tumor model in an immunocompetent syngeneic host

We have examined the effect of adenoviruses expressing soluble transforming growth factor receptorII-Fc (sTGFβRIIFc) in a 4T1 mouse mammary tumor bone metastasis model using syngeneic BALB/c mice. Infection of 4T1 cells with a non-replicating adenovirus, Ad(E1-).sTβRFc, or with two oncolytic adenoviruses, Ad.sTβRFc and TAd.sTβRFc, expressing sTGFβRIIFc (the human TERT promoter drives viral replication in TAd.sTβRFc) produced sTGFβRIIFc protein. Oncolytic adenoviruses produced viral replication and induced cytotoxicity in 4T1 cells. 4T1 cells were resistant to the cytotoxic effects of TGFβ-1 (up to 10 ng ml(-1)). However, TGFβ-1 induced the phosphorylation of SMAD2 and SMAD3, which were inhibited by co-incubation with sTGFβRIIFc protein. TGFβ-1 also induced interleukin-11, a well-known osteolytic factor. Intracardiac injection of 4T1-luc2 cells produced bone metastases by day 4. Intravenous injection of Ad.sTβRFc (on days 5 and 7) followed by bioluminescence imaging (BLI) of mice on days 7, 11 and 14 in tumor-bearing mice indicated inhibition of bone metastasis progression (P<0.05). X-ray radiography of mice on day 14 showed a significant reduction of the lesion size by Ad.sTβRFc (P<0.01) and TAd.sTβRFc (P<0.05). Replication-deficient virus Ad(E1-).sTβRFc expressing sTGFβRIIFc showed some inhibition of bone metastasis, whereas Ad(E1-).Null was not effective in inhibiting bone metastases. Thus, systemic administration of Ad.sTβRFc and TAd.sTβRFc can inhibit bone metastasis in the 4T1 mouse mammary tumor model, and can be developed as potential anti-tumor agents for breast cancer.

Systemic delivery of oncolytic adenoviruses targeting transforming growth factor-β inhibits established bone metastasis in a prostate cancer mouse model

We have examined whether Ad.sTβRFc and TAd.sTβRFc, two oncolytic viruses expressing soluble transforming growth factor-β receptor II fused with human Fc (sTGFβRIIFc), can be developed to treat bone metastasis of prostate cancer. Incubation of PC-3 and DU-145 prostate tumor cells with Ad.sTβRFc and TAd.sTβRFc produced sTGFβRIIFc and viral replication; sTGFβRIIFc caused inhibition of TGF-β-mediated SMAD2 and SMAD3 phosphorylation. Ad(E1-).sTβRFc, an E1(-) adenovirus, produced sTGFβRIIFc but failed to replicate in tumor cells. To examine the antitumor response of adenoviral vectors, PC-3-luc cells were injected into the left heart ventricle of nude mice. On day 9, mice were subjected to whole-body bioluminescence imaging (BLI). Mice bearing hind-limb tumors were administered viral vectors via the tail vein on days 10, 13, and 17 (2.5×10(10) viral particles per injection per mouse, each injection in a 0.1-ml volume), and subjected to BLI and X-ray radiography weekly until day 53. Ad.sTβRFc, TAd.sTβRFc, and Ad(E1-).sTβRFc caused significant inhibition of tumor growth; however, Ad.sTβRFc was the most effective among all the vectors. Only Ad.sTβRFc and TAd.sTβRFc inhibited tumor-induced hypercalcemia. Histomorphometric and synchrotron micro-computed tomographic analysis of isolated bones indicated that Ad.sTβRFc induced significant reduction in tumor burden, osteoclast number, and trabecular and cortical bone destruction. These studies suggest that Ad.sTβRFc and TAd.sTβRFc can be developed as potential new therapies for prostate cancer bone metastasis.

Systemic delivery of a novel liver-detargeted oncolytic adenovirus causes reduced liver toxicity but maintains the antitumor response in a breast cancer bone metastasis model

We are interested in developing oncolytic adenoviruses for the treatment of bone metastasis of cancer. A key limitation of systemic delivery of oncolytic adenovirus type 5 (Ad5) is that the majority of the virus is taken up by the liver, causing liver damage and systemic toxicity. Given that Ad5 hexon binding with blood coagulation factor X is a key factor in liver sequestration, and that a rare serotype, Ad48, has a diminished capacity to bind with factor X, we have generated mHAd.luc2, a novel hexon-chimeric oncolytic adenovirus. To create mHAd.luc2, seven hypervariable regions of Ad5 hexon were substituted with the corresponding regions from Ad48. Compared with Ad5-based oncolytic virus Ad.luc2, intravenous injection of mHAd.luc2 into nude mice resulted in significantly reduced liver uptake. A single high dose (1.0×10(11) viral particles/mouse) of Ad.luc2 resulted in 100% animal death by day 3; whereas none of the mice died in the mHAd.luc2 group. Liver enzyme and liver pathology studies indicated that mHAd.luc2 induced significantly less liver toxicity compared with Ad.luc2. Both mHAd.luc2 and Ad.luc2 exhibited similar binding with breast tumor cells, whereas in the presence of factor X, mHAd.luc2 binding was reduced. Both mHAd.luc2 and Ad.luc2 had nearly equal replication potential in breast cancer cells in vitro. Intravenous injection of mHAd.luc2 and Ad.luc2 into nude mice bearing bone metastases resulted in uptake of the viruses into skeletal tumors, and induced significant inhibition of established bone metastases. Thus, liver-detargeted oncolytic adenovirus can be developed for the treatment of breast cancer bone metastasis.

TGFβ-dependent induction of interleukin-11 and interleukin-8 involves SMAD and p38 MAPK pathways in breast tumor models with varied bone metastases potential

We have delineated TGFβ signaling pathways in the production of osteolytic factors interleukin-8 and interleukin-11 in breast cancer cells with different bone metastases potential. Bone seeking MDA-MB-231(hm) cells expressed higher levels of IL-11, but lower levels of IL-8 compared to MDA-MB-231 cells. MCF-7 cells (mainly osteoblastic) did not express IL-8 or IL-11; MDA-MB-468 cells (weakly metastatic) expressed IL-8, but not IL-11. The up-regulation of IL-11 and IL-8 was associated with the rapid activation of SMAD2/3 and p38 MAPK through the TGFβ/TGFβR system. Analysis of TGFβ receptors indicated that MCF-7 cells do not express TGFβRII, and MDA-MB-468 cells do not express SMAD4. Inactivation of SMAD4 or p38PMAPK gene via RNAi resulted in the inhibition of IL-11 and IL-8 production in MDA-MB-231(hm) cells; and over-expression of SMAD4 gene resulted in IL-11 production in MDA-MB-468 cells. TGFβ-1 induced SMAD3 translocation to the nuclei in MDA-MB-231, MDA-MB-231(hm) as well as in SMAD4 deficient MDA-MB-468, indicating that an alternate non-canonical pathway could be responsible for TGFβ-1 induced cytokine production in MDA-MB-468 cells. Thus, four breast cancer cell lines used in this study show differential expression and up-regulation of the osteolytic factors in response to TGFβ-1 that involves both SMAD pathway, a non-canonical SMAD pathway, as well as p38 MAPK pathways.

Systemic delivery of an oncolytic adenovirus expressing soluble transforming growth factor-β receptor II-Fc fusion protein can inhibit breast cancer bone metastasis in a mouse model

We have investigated whether systemic delivery of an oncolytic adenovirus, Ad.sTβRFc, expressing the soluble form of transforming growth factor-β receptor II fused with human immunoglobulin Fc fragment (sTGFβRIIFc), could inhibit breast cancer bone metastasis in a mouse model. MDA-MB-231 (human breast cancer) cells were inoculated into the left heart ventricles of nude mice. Once the skeletal tumors were visible by X-rays, mice were intravenously injected with either buffer, Ad.sTβRFc, Ad(E1⁻).sTβRFc (a replication-deficient adenovirus expressing sTGFβRIIFc), or Ad.luc2 (a replicating adenovirus expressing firefly luciferase gene). On days 2 and 7 after viral injections, viral replication and sTGFβRIIFc expression were detected in the skeletal tumors in Ad.sTβRFc-treated group; only viral replication in Ad.luc2 group, and sTGFβRIIFc expression in the Ad(E1⁻).sTβRFc group, were detected. To examine the therapeutic effects, buffer or various viral vectors were administered on days 4 and 7 after intracardiac injection of MDA-MB-231 cells. On day 28, X-ray radiography showed a highly significant reduction in lesion size by Ad.sTβRFc, a significant reduction by Ad.luc2, and some reduction by Ad(E1⁻).sTβRFc. Goldner's trichrome and hematoxylin-eosin staining of the bone sections revealed a significant reduction of tumor burden in the Ad.sTβRFc group, but not in the Ad(E1⁻).sTβRFc or Ad.luc2 group. There were significant reductions in free calcium levels by Ad.sTβRFc, Ad(E1⁻).sTβRFc, and Ad.luc2; however, only in the Ad.sTβRFc group were calcium levels reduced to the normal values. These results suggest that concomitant viral replication and sTGFβRIIFc production are important to inhibit bone metastasis and osteolysis, and that Ad.sTβRFc could be developed for targeting breast cancer bone metastases.

A modified hTERT promoter-directed oncolytic adenovirus replication with concurrent inhibition of TGFbeta signaling for breast cancer therapy

Our laboratory is interested to develop oncolytic adenoviral vectors that can be administered systemically for the treatment of breast cancer. To restrict viral replication in breast tumor cells, we have constructed mhTERTAd.sTβRFc, a 01/07 based adenoviral vector expressing the soluble form of TGFβ receptor II fused with human Fc IgG1 (sTGFβRIIFc) gene, in which viral replication is under the control of modified human telomerase reverse transcriptase (mhTERT) promoter. In addition, mhTERTAd.sTβRFc-mediated sTGFβRIIFc production would target growth factor-β (TGFβ) pathway known to contribute to the tumor progression breast cancer metastasis. We chose to use mhTERT promoter because it was found to be relatively more active (approximately 20-times) in breast cancer cells compared to normal human cells. We showed that infection of MDA-MB-231 and MCF-7 breast cancer cells for 48 hrs with mhTERTAd.sTβRFc produced high levels of sTGFβRIIFc (greater than 1 μg/ml) in the medium. Breast cancer cells produced nearly 6,000-fold increase in the viral titers during 48 hrs infection period. However, mhTERTAd.sTβRFc replication was attenuated in normal cells. Infection of breast cancer cells with a replication deficient virus Ad(E1^-).sTβRFc also produced high levels of sTGFβRIIFc, but under these conditions no detectable viral replication was observed. Adenoviral-mediated production of sTGFβRIIFc was shown to bind with TGFβ-1, and abolished the effects of TGFβ-1 on downstream SMAD-3 phosphorylation. The administration of mhTERTAd.sTβRFc intravenously into MDA-MB-231 human xenograft bearing mice resulted in significant inhibition of tumor growth, and production of sTGFβRIIFc in the blood. On the other hand, intravenous injection of Ad(E1^-).sTβRFc did not exhibit significant inhibition of the tumor growth, but resulted in the sTGFβRIIFc in the blood, suggesting that viral replication along with sTGFβRIIFc protein production play a critical role in inducing inhibition of tumor growth. These results warrant future investigation of mhTERTAd.sTβRFc as an anti-tumor agent in vivo.

Exposure to alcohol problems and its association with sexual behaviour and biologically confirmed Trichomonas vaginalis among women living with HIV

OBJECTIVES

Only a small number of studies have examined the association between alcohol use and risky sexual behaviour among women living with HIV, particularly African-American women. The present study examined the association between alcohol problems, sexual behaviour and biologically confirmed sexually transmitted infections (STI) among a sample of predominantly African-American women living with HIV.

METHODS

A sample of 366 women living with HIV between the ages of 18 and 50 years participated in the study. The majority of women were African-American (84.2%). Participants completed a face-to-face interview assessing sociodemographics, sexual behaviour, other substance use and alcohol problems using the CAGE (Cut down, Annoyed, Guilty, Eye opener), a screening measure for alcohol abuse. Participants also provided self-collected vaginal swab specimens that were assayed for STI.

RESULTS

The prevalence of high scores on the CAGE was 54.5% and 15% of women tested positive for Trichomonas vaginalis. Multivariate logistic regression analyses, with age and other substance use as covariates, indicated that women who scored higher on the CAGE, relative to those who scored lower, were more likely to test positive for T vaginalis, have sex with their spouse or steady partner when only they had been drinking and have sex with their spouse or steady partner when they had both been drinking.

CONCLUSIONS

These findings suggest that alcohol assessment should be included in regular healthcare maintenance among women living with HIV. Intervention programmes should be tailored to address alcohol use/abuse among African-American women living with HIV.

Mycobacterial infections in human immuno-deficiency virus seropositive patients: role of non-tuberculous mycobacteria

BACKGROUND

There is high prevalence of tuberculosis in patients with HIV infection; hence the role of non-tuberculous mycobacteria (NTM) in HIV patients has always been undermined. NTM may be responsible for clinical disease in a substantial number of immuno-compromised HIV sero-positive individuals even in a country endemic for Mycobacterium tuberculosis (M. tuberculosis). The study was designed to look for the contribution of NTM to morbidity in HIV seropositive patients.

MATERIAL AND METHODS

In a prospective study of ninety-four HIV seropositive individuals presenting with pulmonary or extra-pulmonary symptoms suggestive of mycobacterial infection, appropriate samples were collected and processed. Detailed clinical history was utilized to differentiate colonization or contamination by NTM from true lung disease.

RESULTS

Fourteen samples grew mycobacterial species, 8(57.2%) being NTM. The distribution of NTM was--3 M. avium complex, 2 M. fortuitum, 2 M. vaccae, 1 M. phlei. 6 isolates were M. tuberculosis.

CONCLUSION

NTM may be responsible for a significant proportion of mycobacterial infections in HIV seropositive individuals. Despite the high endemicity of tuberculosis in developing countries like India, the presence of NTM should be ruled out; especially in immuno-compromised HIV seropositive individuals before instituting anti-tubercular therapy empirically. In addition, non-response of NTM to ATT may be wrongly attributed to multi-drug resistant tuberculosis.

Evaluating apoptosis in tumor cells infected with adenovirus expressing p53 tumor suppressor gene

This chapter describes several methods for recognizing apoptosis in tumor cells following infection with a replication-deficient adenovirus expressing the tumor suppressor gene p53. We include cytotoxicity assays and assays of apoptosis, including DNA-nucleosomal DNA fragmentation (DNA laddering), TUNEL, DAPI staining, analysis of the sub-G1 (subdiploid) population, and degradation of poly(ADP-ribose) polymerase (as assayed by Western blot). Although this is not a comprehensive list of protocols to evaluate apoptosis, we believe that these will cover the majority of conditions of apoptosis that may arise. The chapter also describes the characteristics of each technique, including the advantages and disadvantages of each method.

Development of oncolytic adenovirus armed with a fusion of soluble transforming growth factor-beta receptor II and human immunoglobulin Fc for breast cancer therapy

We have developed an approach to cancer gene therapy in which the oncolytic effects of an adenoviral vector have been combined with selective expression of a soluble form of transforming growth factor (TGF)-beta receptor II fused with Fc (sTGFbetaRIIFc). We chose to use adenoviral dl01/07 mutant because it can replicate in all cancer cells regardless of their genetic defects. An oncolytic adenovirus expressing sTGFbetaRIIFc (Ad.sT- betaRFc) was constructed by homologous recombination. Infection of MDA-MB-231 and MCF-7 human breast cancer cells with Ad.sTbetaRFc produced sTGFbetaRIIFc, which was released into the media. The conditioned media containing sTGFbetaRIIFc could bind with TGF-beta 1 and inhibited TGF-beta-dependent transcription in target cells. Infection of MDA-MB-231, MCF-7, and 76NE human breast cancer cells with Ad.sTbetaRFc resulted in high levels of viral replication, comparable to that of a wild-type dl309 virus. Although some viral replication was observed in actively dividing normal human lung fibroblasts, there was no replication in nonproliferating normal cells. Direct injection of Ad.sTbetaRFc into MDA-MB-231 human breast xenograft tumors grown in nude mice resulted in a significant inhibition of tumor growth, causing tumor regression in more than 85% of the animals. These results indicate that it is possible to construct an oncolytic virus expressing sTGFbetaRIIFc in which both viral replication and transgene expression remain intact, and the recombinant adenovirus is oncolytic in a human tumor xenograft model. On the basis of these results we believe that it may be feasible to develop a cancer gene therapy approach using Ad.sTbetaRFc as an antitumor agent.

Detection of Human Immunodeficiency Virus Type 1 (HIV-1) A/AE Circulating Recombinant Form (CRF) in India: Possible Implications

BACKGROUND

Rapidly evolving viruses such as human immunodeficiency virus (HIV-1) develop marked sequence differences in their genome over the course of an epidemic and in individuals infected for longer duration. This is because of the error prone reverse transcriptase (RT), which rapidly incorporates mutations resulting in genomic diversity, altered cell tropism, immune escape, and variable resistance to antiretroviral drugs. As a result, radically different genomic combinations may be generated in individuals infected by genetically diverse viruses that have mosaic genomes.

METHODS

Whole blood sample was collected from 25 HIV-1 infected patients. Chromosomal DNA was isolated from the patient's peripheral blood mononuclear cells (PBMCs). Full-length gag gene (~1.5 kb) was amplified. PCR products were subjected to direct automated sequencing. For identification of recombinants Simplot version 2.5 was used.

RESULTS

Out of 25 gag genes that were sequenced, the gene amplified from a 29 years old HIV-1 seropositive male revealed a putative recombinant sequence. This sequence showed maximum homology with HIV-1 subtype A. Simplot analysis revealed the sequence to be a likely recombinant with the following composition: Initial stretch of 1 to 200 nucleotides representing AE circulating recombinant form (CRF), 201 to 440 nucleotides representing HIV-1 subtype A, 441 to 660 nucleotides representing AE CRF again, 661 to 700 nucleotides representing HIV-1 subtype A and the remaining stretch of the nucleotides from 701 to 1076 representing AE CRF.

CONCLUSION

We document a putative HIV-1 subtype A/ AE CRF. It is important to monitor various CRFs that are being generated and horizontally spread in the community. This has significant implications for development of candidate vaccine for India.

Co-infection by Semliki forest virus and malarial parasite modulates viral multipucation, pathogenesis and cytokines in mice

Environmental, technological and societal factors continue to have a dramatic effect on infectious diseases worldwide and are considered to be facilitating the emergence of several infectious diseases at a time. Co-infection with different species of viral and malaria infections are currently emerging problems of dual infection in the developing as well as developed countries. Understanding of interactions between the host, malaria and virus infection is of current concern and we have initiated studies to delineate the mechanisms involved during the progression of Semliki forest virus (SFV) and Plasmodium yoelii (P. yoelii) infection in mice. Enhanced virus multiplication and up-regulation of cytokine mRNA level in P. yoelii and SFV co-infected mice were observed on day 4 post-infection compared to respective controls. Collectively, our observations indicate that malaria infection may influence virus multiplication, pathogenesis and up-regulation of cytokine mRNA during co-infection in mice.

An oncolytic adenovirus expressing soluble transforming growth factor-β type II receptor for targeting breast cancer: in vitro evaluation

In recent years, adenoviruses that selectively replicate in tumor cells have been developed. However, there is a tremendous need to improve their anticancer efficacy. We wish to investigate whether a strategy that combines the oncolytic effects of an adenoviral vector with simultaneous expression of soluble form of transforming growth factor-beta type II receptor (sTGFbetaRII) offers a therapeutic advantage. We chose to target TGF-betas because they play a pivotal role in late-stage tumorigenesis by enhancing tumor invasion and metastasis. A sTGFbetaRII cDNA was cloned in conditionally replicating adenoviral vector rAd-sTRII and in a replication-deficient adenovirus Ad-sTRII. Infection of MDA-MB-231 breast cancer cells with rAd-sTRII or Ad-sTRII followed by Western blot analysis indicated the expression of diffused glycosylated forms of sTGFbetaRII that were also secreted into the extracellular medium. The secreted proteins were shown to bind with TGF-beta and antagonize TGF-beta-induced p38 mitogen-activated protein kinase activity. However, marked differences in the replication potential of rAd-sTRII and Ad-sTRII were observed in breast tumor cells. Infection of MDA-MB-231 cells with rAd-sTRII resulted in cytotoxicity and significant increase in the adenoviral titers that were comparable with a wild-type adenovirus dl309. However, Ad-sTRII was much less toxic to the tumor cells, and the viral titers of Ad-sTRII remained relatively unchanged. These results suggest that the infection of breast tumor cells with conditionally replicating adenoviral vector rAd-sTRII produced sTGFbetaRII that can abrogate TGF-beta signaling while maintaining the replication potential of the virus, indicating that rAd-sTRII could be a potential anticancer agent.

Characterization of HIV-1 Gag-specific T cell responses in chronically infected Indian population

India is at the epicentre of the global HIV/AIDS epidemic in South-east Asia, predominated by subtype C infections. It is important to characterize HIV-1-specific T cell responses in this particular population with the aim of identifying protective correlates of immunity to control HIV-1 infection. In this study, we performed a comprehensive analysis of the breadth and magnitude of T cell responses directed at HIV-1 subtype C Gag, one of the most conserved HIV-1 proteins. The study population consisted of antiretroviral naive, chronic HIV-1 subtype C-infected individuals at various stages of infection. We used recent advanced techniques such as enzyme-linked immunospot (ELISPOT) assay and intracellular cytokine staining to quantify the total CD4(+) and CD8(+) T cell response to HIV-1 gag at single peptide level, regardless of HLA haplotype of the infected individual. The p24-Gag was identified as the most frequently recognized subunit protein with the greatest magnitude of CD4(+) and CD8(+) T cell responses. Stronger and broader CD8 T cell responses were recognized, contrasting with the weaker and narrower CD4 T cell responses with regard to Gag protein subunits. The magnitude of the HIV-specific interferon (IFN)-gamma responses was observed to be higher than the corresponding interleukin (IL)-2 response, indicating the persistence of antigenic load in chronically infected Indian population due to the probable dysfunction of HIV-specific, IFN-gamma-secreting CD8 T cells in absence of IL-2 help.

Human brain derived cell culture models of HIV-1 infection

During the clinical course of acquired immune deficiency syndrome, infection of the CNS by human immunodeficiency virus-1 (HIV-1) may ultimately result in the impairment of cognitive, behavioral and motor functions. Viral neuropathogenesis involves inflammatory molecules and neurotoxins produced from infected and immune-activated lymphocytes, microglial cells and astrocytes. Here, we discuss the current understanding of HIV-1 infection of the CNS and various cell culture systems from the developing human brain in order to study the neurobiology of HIV-1 infection, the mechanisms contributing to HIV-1 infection, and disease progression.

CDC staging based on absolute CD4 count and CD4 percentage in an HIV-1-infected Indian population: treatment implications

CD4+ T-cell levels are an important criterion for categorizing HIV-related clinical conditions according to the CDC classification system and are therefore important in the management of HIV by initiating antiretroviral therapy and prophylaxis for opportunistic infections due to HIV among HIV-infected individuals. However, it has been observed that the CD4 counts are affected by the geographical location, race, ethnic origin, age, gender and changes in total and differential leucocyte counts. In the light of this knowledge, we classified 600 HIV seropositive antiretroviral treatment (ART)-naïve Indian individuals belonging to different CDC groups A, B and C on the basis of CDC criteria of both CD4% and CD4 counts and receiver operating characteristic (ROC) curves were generated. Importantly, CDC staging on the basis of CD4% indicated significant clinical implications, requiring an early implementation of effective antiretroviral treatment regimen in HIV-infected individuals deprived of treatment when classified on the basis of CD4 counts.

Vector-mediated cancer gene therapy: an overview

In recent years there has been a dramatic increase in developing gene therapy approaches for the treatment of cancer. The two events that have permitted the formulation of concept of cancer gene therapy are the new understanding of the molecular mechanisms underlying oncogenesis, and the development of the DNA-delivery vehicles or vectors. Many approaches to cancer gene therapy have been proposed, and several viral and non-viral vectors have been utilized. The purpose of this review article is to describe the various strategies of cancer gene therapy (transfer of tumor suppressor genes, suicide genes-enzyme/pro-drug approach, inhibition of dominant oncogenes, immunomodulation approaches, expression of molecules that affect angiogenesis, tumor invasion and metastasis, chemosensitization and radiosensitization approaches, and chemoprotection of stem cells). The chapter also reviews the commonly used vectors (retroviral vectors, adenoviral vectors, adeno-associated viral vectors, pox viruses, herpes simplex viruses, HIV- vectors, non-viral vectors and targetable vectors) for cancer gene therapy. Some of the important issues in cancer gene therapy, and the potential future directions are also being discussed.

Targeting TGFbeta signaling for cancer therapy

Transforming growth factor (TGF) betas are multifunctional polypeptides that regulate several cellular functions, including cell growth and differentiation, extra cellular matrix production, motility and immunosuppression. The growth-inhibiting properties of TGFbeta have gained much attention into its role as a tumor suppressor. There is, however, now increasing evidence that TGFbeta switches roles, from tumor suppressor to tumor promoter, as the tumor progresses. Given the integral role of TGFbeta in the tumor progression, it follows that TGFbeta signaling offers an attractive target for cancer therapy. Several strategies including the use of antisense oligonucleotides for TGFbeta, TGFbeta antibodies, dominant negative TGFbeta receptor II, and small drug-molecules to inhibit TGFbeta receptor I kinase have shown great promise in the preclinical studies. These new findings, coupled with progressing clinical trials indicate that inhibition of TGFbeta signaling may, indeed, be a viable option to cancer therapy. This review summarizes the TGFbeta signaling, the dual role of TGFbeta--as a tumor suppressor and tumor promoter, and various strategies targeted against TGFbeta signaling for cancer therapy. The next few years promise to better our understanding of approaching cancer therapy with an eye to the inhibition of TGFbeta signaling.

Rat Sodium Iodide Symporter for Radioiodide Therapy of Cancer

Design and development of new approaches for targeted radiotherapy of cancer and improvement of therapeutic index by more local radiation therapy are very important issues. Adenovirus-mediated delivery of the sodium iodide symporter (NIS) gene to cancer cells is a powerful technique to concentrate lethal radiation in tumor cells and eradicate tumors with increased therapeutic index. A replication-defective adenoviral vector expressing the rat NIS gene (Ad-rNIS) was used for in vitro gene delivery and into human prostate cancer xenografts to study antitumor effect. Robust function of the rat symporter was detected in DU145, T47D, and HCT-15 human cancer cell lines transduced with Ad-rNIS. All three cancer cell lines successfully transferred functionally active rat symporter to the plasma membrane, resulting in very high levels of iodine-125 accumulation. Three-dimensional multicellular tumor spheroids derived from DU145 human prostate cancer cells were transduced with Ad-rNIS and incubated with (131)I for 24 hours. After treatment, spheroids rapidly decreased in size and disappeared within 10 days. In vivo data revealed an inhibition of tumor growth in athymic nude mice after intratumoral Ad-rNIS injection followed by (131)I administration. Eighty-eight percent of experimental mice survived >30 days, whereas control groups had only 18% survival >30 days. This is the first report that demonstrates the rat NIS gene can effectively induce growth arrest of human tumor xenografts after in vivo adenoviral gene delivery and (131)I administration. The data confirm our hypothesis that the rat NIS gene is an attractive suicide gene candidate for cancer treatment.

Reduced susceptibility to ciprofloxacin and gyra gene mutation in North Indian strains of Salmonella enterica serotype Typhi and serotype Paratyphi A

The emergence of reduced susceptibility to ciprofloxacin among Salmonella enterica serotype Typhi and serotype Paratyphi A leading to clinical failure of treatment poses a great therapeutic challenge. The mechanism of fluoroquinolone resistance in clinical isolates of S. Typhi and S. Paratyphi A is not very well documented. The present study was carried out with the objective of molecular characterization of reduced quinolone susceptibility amongst the strains of S. Typhi and S. Paratyphi A isolated from the patients with enteric fever during January, 2000, to April, 2003, in a North Indian hospital. A total of 422 culture-positive cases of enteric fever were reported to the hospital during the period of study, of which S. Typhi was isolated from 350 cases and S. Paratyphi A from 72 cases. The antimicrobial susceptibility of these strains was determined by disk diffusion and agar dilution method according to NCCLS guidelines, and E-test method. A total of 140 randomly selected strains, isolated during the years 1993-1999, that were available from the laboratory stocks were also studied to compare with the present strains. To study the quinolone susceptibility, the strains were divided into nalidixic acid sensitive (NAS), nalidixic acid intermediate resistant, (NAI) and nalidixic acid resistant (NAR) on the basis of susceptibility to nalidixic acid. Clinical history was available from 174 patients, of which 93 needed hospitalization due to severe disease. Of these, 82 patients were infected with NAR strains and 22 patients had a documented evidence of clinical failure to ciprofloxacin therapy. The patients infected with NAR strains were younger and had a significantly longer duration of fever (p value < 0.05) than those infected with NAS strains. It was observed that the proportion of NAR strains increased gradually over the years. These strains had a significantly higher range of MIC of ciprofloxacin (0.023-1.0 microg/ml) as compared to the NAS strains (0.002-0.125 microg/ml) (p value < 0.05). The sequencing of quinolone resistance determining region (QRDR) of the gyrA gene showed the presence of mutation at either Ser 83 or at Asp 87 in all the NAR and NAI strains. None of the NAS strains had a mutation, suggesting that the gyrA gene mutation is sufficient to confer resistance to nalidixic acid and reduced susceptibility to ciprofloxacin. This mutation, although phenotypically expressed as decreased susceptibility to ciprofloxacin, goes undetected by the disk diffusion method using the present NCCLS guidelines. Hence, it can increase morbidity and mortality due to delay in appropriate antibiotic treatment.

Second allogeneic bone marrow transplantation after myeloablative conditioning analysis of 43 cases from single institution

Between March 1984 and December 1999, a total of 43 second related allogeneic BMT procedures after myeloablative conditioning were carried out in our institution, 37 following allogeneic, and 6 following autologous BMT. Thirty one patients were males (72%). At 1st BMT (BMT1), median age was 11.5 years (range, 0.16-45 years). BMT1 was carried out for the diagnosis of AML in 13 patients (30%), SAA in nine (21%), ALL in six (14%), CML in six (14%), immunodeficiency in three (7%), NHL in two, beta-thal in two, HD in one, Red cell aplasia in one. HLA matching status for allogeneic BMT1 was full match in 33, one antigen mismatch in two and haplo identical in two patients. Median age at the 2nd BMT (BMT2) was 14 years (range, 0.41-46.7 years). Indications for BMT2 were recurrent hematologic neoplasm in 23 patients (53%), primary graft failure in 12 (28%) and late graft failure in 8 (19%). Median time from BMT1 to recurrence of hematologic neoplasm or late graft failure was 10 months (range, 2.5- 88 months). Median BMT1 to BMT2 interval was 13 months (range, 1-107 months). For BMT2, the same donor was used in 29 patients, while 14 patients had alternate related donor (12 full match, 1-one Ag mismatch, 1 haplo identical). A different conditioning regimen was used in the majority of the patients (39, 91%). Radiation containing conditioning regimen were used mostly for patients previously conditioned with chemotherapy only for BMT1 and chemotherapy conditioning +/- ATG for those who received radiation containing conditioning at BMT1. Bone marrow was the stem cell source for all patients at BMT2 and all except three autologous peripheral stem cell transplantation patient at BMT1. Significant organ toxicity leading to procedure related death in 13 patients (30%) was observed after BMT2. At a median follow up of 36 months after BMT2, 22 patients (51%) are alive (20 free of disease, 2 with recurrent disease) with overall median survival of 47.5 (SD +/- 9) months. Univariate analysis of relevant clinical factors identified the following variables as the only statistically significant favorable prognostic factors for overall survival: BMT1-BMT2 interval of > or = 6 months (P=0.0007) and age at BMT2 < or = 10 years (P=0.041). The nature of underlying disease (neoplastic or non-neoplastic) was not statistically significant (P=0.23). There was no statistically significant difference in survival outcome of BMT2 using same donor vs. alternate related donor (P=0.51). Due to the relatively limited sample size, multivariate analysis was not attempted. This single institution study suggests that second allogeneic BMT after myeloblative conditioning has an acceptable treatment related morbidity/mortality and favorable outcome if performed at age < or = 10 years and with an interval of > or = 6 months after the first BMT. Additionally same donor can successfully be used for the second transplant with similar survival outcome to alternate donor.

Evaluation of CD4 counts and percentages in the HIV infected Indian population

This study was designed to evaluate the absolute CD4+ counts and percentages in HIV subtype C infected patients at a tertiary care hospital in northern India. The CD4+ counts of 377 HIV seropositive subjects were estimated by a FACS Calibur (BD) flow cytometer. Dual color immunophenotyping was performed on each sample, which was acquired and analysed using CellQUEST software. Discordance between CD4+ counts and percentages were found more in the early stage ie Group A (37.2%) when compared with Group B (31.6%) and Group C (28.8%), with the counts remaining in the normal range but percentages being severely depressed.

Adenovirus expressing p27KIP1 induces apoptosis against cholangiocarcinoma cells by triggering Fas ligand on the cell surface

BACKGROUND/AIMS

The prognosis of patients with cholangiocarcinoma is poor because of the difficulty of surgical curative resection. Therefore, other effective treatments must be developed especially those involving gene therapy. p27kip1, one of the cyclin-dependent kinase inhibitors, is known to limit proliferation of the cells. Our previous reports have shown that the overexpression of p27kip1 by a recombinant adenoviral vector expressing p27kip1 (Adp27) induces apoptosis. However, the mechanism of the Adp27-mediated apoptosis is not still resolved. Activation of the Fas pathway is one of the important gates for apoptosis. In this report, we examined whether p27kip1-induced apoptosis is closely related to the Fas/Fas ligand (FasL) system.

RESULTS

After infection of Adp27, flow cytometric analysis showed that Fas ligand was expressed on the cell surface of cholangiocarcinoma cell lines (TFK-1). In spite of detecting the cell surface expression of Fas ligand, overexpression of p27kip1 increased no amount of Fas ligand in mRNA by quantitative RT-PCR and protein level by Western blot. In addition, the immunocytochemical analysis showed that Fas ligand was adequately stored within the cytosol of TFK-1 cells. More interestingly, Adp27-induced apoptosis was completely inhibited by the neutralizing antibody of Fas ligand (NOK-1). This result suggests that overexpression of p27kip1 may deliver Fas ligand to the cell surface and mainly utilizes the Fas pathway as a gate of apoptosis.

CONCLUSIONS

This is the first report to prove that Adp27-mediated apoptosis utilizes the Fas pathway by delivering Fas ligand to the cell surface.

Spectrum of Opportunistic Infections and Profile of CD4+ Counts among AIDS Patients in North India

BACKGROUND

As the number of AIDS cases increases in India, information available among clinicians about the prevalence of opportunistic infections (OIs) is scarce. The aim of the present study was to document the characteristic OIs of HIV-infected North Indian patients along with their CD4+ counts.

PATIENTS AND METHODS

The study group consisted of subjects with confirmed serodiagnosis of HIV, attending the medical clinics at a tertiary health care center in North India. The CD4+ counts were estimated by FACS Calibur (BD) flow cytometer. Simultaneously, routine microbiology smears, cultures and serology were performed to confirm OI.

RESULTS

In this retrospective study of 421 subjects, the predominant OI was tuberculosis (47%, 189 cells/ micro l), followed by parasitic diarrhea (43.5%, 227 cells/ micro l) and oral candidiasis (25.2%, 189 cells/ micro l).

CONCLUSION

Tuberculosis was the most frequent OI in the HIV-infected patients studied, and the major mode of transmission of HIV was by sexual route. The median CD4+ counts observed were lower when compared to other studies.

Increasing HIV seropositivity among adult tuberculosis patients in Delhi

We report the HIV seropositivity among adult TB patients from our hospital, a tertiary care hospital in north India between 2000-2002. Of the 555 patients with various forms of tuberculosis, 52 were found to be seropositive (9.4%). In 1994-1999, the HIV seropositivity in this hospital was only 0.4 per cent (2 of 500 patients). This communication describes a dramatic increase in seropositivity and highlights the importance of continued HIV serosurveillance in patients with TB.