Profiling gene mutations, translocations, and multidrug resistance in pediatric acute lymphoblastic leukemia: a step forward to personalizing medicine.

Precise risk stratification and tailored therapy in acute lymphoblastic leukemia (ALL) can lead to enhanced survival rates among children. Translocations and mutations along with multidrug resistance markers are important factors that determine therapeutic efficacy. Gene mutation profiling of patients at the time of diagnosis can offer accurate clinical decision-making. Multiplex PCR was used to screen for various translocations, mutations, and P-glycoprotein (P-gp) status in pediatric ALL samples. The roles of P-gp were analyzed at the transcriptional and translational levels by using real-time PCR and immunoblotting, respectively. ALL specific cell line Jurkat was used to validate the functional role of P-gp in imparting drug resistance by siRNA knockdown studies. Co-occurrence of translocations and mutations contributes to cellular drug resistance. Presence of any translocation in addition to FLT3/ITD hints for overactive P-gp. Co-occurrence of E2A/PBX and TEL/AML has also been positively correlated with P-gp status. Multiplex PCR provides a rapid and cost effective technique for profiling translocations, mutations, and multidrug resistance status that determines what therapy patients could be administered. Mutation profiling in patients for analyzing genetic lesions along with drug resistance profiling will help improve risk stratification and personalized medicine, thereby increasing the treatment success rates among pediatric patients with leukemia.

Downregulation of MicroRNA-152 contributes to high expression of DKK1 in multiple myeloma.

Multiple myeloma (MM) induced bone lesion is one of the most crippling characteristics, and the MM secreted Dickkopf-1 (DKK1) has been reported to play important role in this pathologic process. However, the underlying regulation mechanisms involved in DKK1 expression are still unclear. In this study, we validated the expression patterns of microRNA (miR) 15a, 34a, 152, and 223 in MM cells and identified that miR-152 was significantly downregulated in the MM group compared with the non-MM group, and that miR-152 level was negatively correlated with the expression of DKK1 in the MM cells. Mechanistic studies showed that manipulating miR-152 artificially in MM cells led to changes in DKK-1 expression, and miR-152 blocked DKK1 transcriptional activity by binding to the 3'UTR of DKK1 mRNA. Importantly, we revealed that MM cells stably expressing miR-152 improved the chemotherapy sensitivity, and counteracted the bone disruption in an intrabone-MM mouse model. Our study contributes better understanding of the regulation mechanism of DKK-1 in MM, and opens up the potential for developing newer therapeutic strategies in the MM treatment.

Sonic hedgehog-glioma associated oncogene homolog 1 signaling enhances drug resistance in CD44(+)/Musashi-1(+) gastric cancer stem cells.

Drug resistance in gastric cancer largely results from the gastric cancer stem cells (GCSCs), which could be targeted to improve the efficacy of chemotherapy. In this study, we identified a subpopulation of GCSCs enriched in holoclones that expressed CD44(+)/Musashi-1(+) stem cell biomarkers, capable of self-renewal and proliferation. Enriched CD44(+)/Musashi-1(+) GCSCs demonstrated elevated expression of sonic hedgehog (SHH) and glioma-associated oncogene homolog 1 (GLI1), the well-known signaling pathway molecules involved in the drug resistance. Further, CD44(+)/Musashi-1(+) cells exhibited high drug efflux bump activity and were resistant to doxorubicin (Dox)-induced apoptosis, and unregulated the ATP-binding cassette sub-family G member 2 (ABCG2) expression,. The above effects on apoptosis were reversed in the presence of GLI inhibitors, GANT61 and GDC-0449, or by the knockdown of GLI1/SHH. Upon knockdown of GLI1, expression of ABCG2 was downregulated the antitumor effects were significantly improved as observed in the gastric cancer xenograft. Collectively, our study revealed that co-expression of CD44(+)/Musashi-1(+) could be used to identify GCSCs, which also accounts for the drug resistance in gastric cancer. SHH-GLI and its downstream effector ABCG2 could be better targeted to possibly improve the efficacy of chemotherapy in drug-resistant gastric cancers.

Anticancer activity of galactoxyloglucan polysaccharide-conjugated doxorubicin nanoparticles: Mechanistic insights and interactome analysis.

Toxicity associated with chemotherapeutic drugs such as doxorubicin (Dox), is one of the major obstacles that is currently affecting patients. PST-Dox (Galactoxyloglucan, PST001-conjugated Dox) nanoparticles were synthesized by encapsulating Dox with polysaccharide PST001, isolated from Tamarindus indica (Ti) by ionic gelation with tripolyphosphate (TPP). Herein, we demonstrate a detailed mechanistic and interactome network analysis that is specific to PST-Dox action in cancer cells and normal lymphocytes. Our results show that PST-Dox is superior to its parental counterparts, exhibiting a greater cytotoxicity by the induction of apoptosis against a wide variety of cancers by enhanced cellular uptake of Dox from the nanoparticle conjugates. Also, PST-Dox nanoparticles were non-toxic to normal lymphocytes with limited immunostimulatory effects up to certain doses. Elucidation of molecular mechanism by whole genome microarray in cancer cells and lymphocytes revealed that a large number of genes were dysregulated specifically in cancer cells. Specifically, a unique target gene EGR1, contextually determined translational activation of P53 in the cancerous and non-cancerous cells. Most of the key downregulated genes were tyrosine kinases, indicating the potential inhibitory action of PST-Dox on tyrosine kinase oncogenic pathways. Western blotting of proteins corresponding to the genes that were altered at the genomic level was very well correlated in the majority of them, except in a few that demonstrated post-transcriptional modifications. The important findings and highly disciplined approaches highlighted in the present study will speed up the therapeutic potential of this augmented nanoparticle formulation for more robust clinical studies and testing in several cancers.

TRAIL-based tumor sensitizing galactoxyloglucan, a novel entity for targeting apoptotic machinery.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an attractive target for cancer therapy due to its ability to selectively induce apoptosis in cancer cells, without causing significant toxicity in normal tissues. We previously reported that galactoxyloglucan (PST001) possesses significant antitumor and immunomodulatory properties. However, the exact mechanism in mediating this anticancer effect is unknown. This study, for the first time, indicated that PST001 sensitizes non-small cell lung cancer (A549) and nasopharyngeal (KB) cells to TRAIL-mediated apoptosis. In vitro studies suggested that PST001 induced apoptosis primarily via death receptors and predominantly activated caspases belonging to the extrinsic apoptotic cascade. Microarray profiling of PST001 treated A549 and KB cells showed the suppression of survivin (BIRC5) and anti-apoptotic Bcl-2, as well as increased cytochrome C. TaqMan low density array analysis of A549 cells also confirmed that the induction of apoptosis by the polysaccharide occurred through the TRAIL-DR4/DR5 pathways. This was finally confirmed by in silico analysis, which revealed that PST001 binds to TRAIL-DR4/DR5 complexes more strongly than TNF and Fas ligand-receptor complexes. In summary, our results suggest the potential of PST001 to be developed as an anticancer agent that not only preserves innate biological activity of TRAIL, but also sensitizes cancer cells to TRAIL-mediated apoptosis.

Co-encapsulation of Doxorubicin with galactoxyloglucan nanoparticles for intracellular tumor-targeted delivery in murine ascites and solid tumors.

Doxorubicin (Dox) treatment is limited by severe toxicity and frequent episodes of treatment failure. To minimize adverse events and improve drug delivery efficiently and specifically in cancer cells, encapsulation of Dox with naturally obtained galactoxyloglucan polysaccharide (PST001), isolated from Tamarindus indica was attempted. Thus formed PST-Dox nanoparticles induced apoptosis and exhibited significant cytotoxicity in murine ascites cell lines, Dalton's lymphoma ascites and Ehrlich's ascites carcinoma. The mechanism contributing to the augmented cytotoxicity of nanoconjugates at lower doses was validated by measuring the Dox intracellular uptake in human colon, leukemic and breast cancer cell lines. PST-Dox nanoparticles showed rapid internalization of Dox into cancer cells within a short period of incubation. Further, in vivo efficacy was tested in comparison to the parent counterparts - PST001 and Dox, in ascites and solid tumor syngraft mice models. Treatment of ascites tumors with PST-Dox nanoparticles significantly reduced the tumor volume, viable tumor cell count, and increased survival and percentage life span in the early, established and prophylactic phases of the disease. Administration of nanoparticles through intratumoral route delivered more robust antitumor response than the intraperitoneal route in solid malignancies. Thus, the results indicate that PST-Dox nanoparticles have greater potential compared to the Dox as targeted drug delivery nanocarriers for loco regional cancer chemotherapy applications.

Six cases of aggressive natural killer-cell leukemia in a Chinese population.

Aggressive natural killer cell leukemia (ANKL) is a rare hematological malignancy that is particularly common among the Asian population. In the current study, we retrospectively evaluated six Chinese ANKL patients, including five males and one female, with a median age of 42 years (range 22 to 50 years). A number of unusual pathogenic manifestations were found in these ANKL patients, such as isolated extraocular muscle involvement, and hemophagocytic syndrome (HPS) with acute renal failure and multiple cavity effusion. Four of the patients died between two and six months after the diagnosis; however, there were two ANKL cases whose clinical behavior differed from the typical clinical course. One survived for over 30 months after splenectomy and chemotherapy treatment, and another ANKL case derived from chronic lymphoproliferative disorders of NK-cells (CLPD-NK) was treated with allogeneic bone marrow transplant (allo-BMT) and survived over 18 months. In conclusion, four cases experienced an aggressive clinical course whereas two demonstrated an indolent manifestation of their disease. New therapeutic regimens including allo-BMT should be optimized in order to improve outcomes of this disease.

Maintenance of immunological homeostasis by Indukantha ghritha in patients with recurrent upper respiratory tract infections-a pilot study.

Indukantha Ghritha (IG), a polyherbal drug used for centuries in Ayurveda, is claimed to be successful in the treatment of respiratory diseases and as a rejuvenating drug. To date, little is known about the immunomodulatory role of IG in recurrent upper respiratory tract infections (RURIs). This study was designed to scientifically validate and evaluate the immunological response mechanisms in patients with RURI. Primarily, immunological functioning of the lymphocyte subsets, Th1 and Th2 cytokines, and immunoglobulins was evaluated before and after administration of IG in patients (n=48) and normal subjects (n=25) for a period of 28 days. Flow cytometry revealed a significant increase in the CD3+, CD4+ T cells and CD56+ natural killer cells with a concomitant reduction of percentage of B cells during IG treatment. Increased Th1 cytokines, IL-2 and IFN-γ, and decreased Th2 cytokine, IL-4, were also observed with IG treatment. IgG was markedly decreased, and IgM was increased with no changes in IgA. Assessment of liver and kidney functions and cholesterol levels was within normal limits in patients administered IG, which reinforces its drug utility as a non-toxic polyherbal drug. Overall, IG provides symptomatic relief by functioning as a potent immunostimulator that can induce type 1 and decrease type 2 immune responses thereby maintaining immunological homeostasis in RURI patients.

Antitumor activity of galactoxyloglucan-gold nanoparticles against murine ascites and solid carcinoma.

Galactoxyloglucan polysaccharide (PST001), isolated from the seed kernels of Tamarindus indica (Ti), was used both as reducing and capping agent for the preparation of gold nanoparticles (PST-Gold) of 20 nm size. The present study evaluated the anticancer effects of the PST-Gold nanoparticles both in vitro and in vivo. The cytotoxicity was evaluated in the murine cancer cell lines, Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC). Galactoxyloglucan-gold nanoparticles (PST-Gold) not only retained the anticancer effects of PST001, but also showed enhanced cytotoxicity via induction of apoptosis even at lower doses and lesser incubation times. In vivo antitumor activity was tested in DLA and EAC murine ascites and EAC solid-tumor syngeneic mouse models. PST-Gold nanoparticles reduced tumor burden and increased median survival and life span significantly in both tumor models compared to the controls. The PST-Gold nanoparticles were very effective as a chemopreventive agent, showing the best overall response when administered prior to tumor induction. In the case of solid tumors, intratumoral administration of the PST-Gold nanoparticles yielded significant results with regard to survival and increment in lifespan as compared to intraperitoneal mode of drug administration. Further studies in higher animal models and in patients at high-risk for recurrence are warranted to fully explore and develop the potential of PST-Gold nanoconjugates as a chemopreventive and therapeutic anti-cancer agent.

Chemopreventive efficacy of Aegle marmelos on murine transplantable tumors.

Emerging trends for cancer chemotherapy show promising developments with the better understanding of molecules delivering more potent and powerful capabilities. But these are severely limited because of increased side effects and higher probability of tumor recurrence. In this scenario, putative exploration of the indigenous and untapped resources modulating immune system to deliver adequate but potent chemopreventive effects appeals considerable interest. However, these require rigorous scientific validation with regard to potency compared with the existing drugs. Aegle marmelos (Linnaeus) Correa (family Rutaceae), a plant component of polyherbal formulation, Indukantha Ghritha, is known for its widespread medicinal values. But the chemopreventive potential has not been explored in comparison to existing anticancer agents. Our attempt contributes the scientific evidence for beneficial immunoprophylactic and antitumor functions in mice challenged with ascites tumors, Dalton's lymphoma ascites, and Ehrlich's ascites carcinoma either alone or in combination with cyclophosphamide and 5-fluorouracil. Specifically, the petroleum ether extracts of this plant (AM(PE)) prophylactically activated a cascade of host defense mechanisms by stimulating or restoring total white blood cell count, macrophage phagocytosis, hematopoiesis, lymphocyte proliferation and functions (CD4+ and CD8+) either naturally or under conditions of impaired immunity like in ascites tumor or during standard agent chemotherapy. Overall, AM(PE) also elicited strong antitumor effects by increasing median survival time and life span, while reducing murine ascites tumor volume and viable tumor counts on par with cyclophosphamide and 5-fluorouracil especially when administered prophylactically. This study also identified 2 putative components, xanthorrhizol and marmelosin, which could be imparting the immunoprophylactic and antitumor effects in transplantable tumor models. Thus, our attempts provide sufficient proof to warrant further to test this drug in higher animal models or in patients with high risk for tumor recurrence and/or immunocompromised diseases.

Nucleus pulposus cells derived IGF-1 and MCP-1 enhance osteoclastogenesis and vertebrae disruption in lumbar disc herniation.

STUDY DESIGN: Chronic strained lumbar disc herniation (LDH) cases were classified into bulging LDH, herniated LDH and prolapse LDH types according to imaging examination, and vertebrae disruptions were evaluated. Cytokines derived from the nucleus pulposus cells were detected, and their effects on osteoclastogenesis, as well as the mechanisms involved, were studied via an in vitro osteoclast differentiation system. OBJECTIVE: To clarify the mechanisms of lumbar vertebrae resorption induced by lumbar herniation. SUMMARY AND BACKGROUND DATA: Chronic strained lumbar disc herniation induced vertebrae erosion exacerbates quality of patients' life and clinical outcome. Although nucleus pulposus cells derived cytokines were reported to play an important role in this pathogenesis, the fundamental mechanisms underlying this process are still unclear. METHODS: Chronic strained lumbar disc herniation patients were diagnosed with CT scan and T2-weighted magnetic resonance imaging. RNA was extracted from 192 surgical specimens of the herniated lumbar disc and 29 surgical excisions of the lumbar disc from spinal injury patients. The expressions of osteoclastogenesis related cytokines and chemokines were examined using real time PCR. Monocytes were induced into osteoclast with M-CSF and RANKL in vitro, while the IGF-1 and MCP-1 were added into the differentiation procedure in order to evaluate the effects and explore the molecular mechanisms. RESULTS: Vertebrae erosion had a positive relationship with lumbar disc herniation severity types. In all of the osteoclastogenesis related cytokines, the IGF-1 and MCP-1 were the most highly expressed in the nucleus pulposus cells. IGF-1 enhances activation of NF-kB signaling directly, but MCP-1 upregulated the expression of RANK, so that enhanced cellular sensitivity to RANKL resulted in increasing osteoclastogenesis and activity. CONCLUSION: Lumbar herniation induced overexpression of IGF-1 and MCP-1 in nucleus pulposus cells aggravated vertebral erosions. Hence, this study suggests that targeting osteoclastogenesis related cytokines has potential clinical significance in the treatment of lumbar disc herniation patients.

Galactoxyloglucan-modified nanocarriers of doxorubicin for improved tumor-targeted drug delivery with minimal toxicity.

Doxorubicin (Dox) is commonly used to treat human malignancies, and the efficacy of Dox can be maximized by limiting toxicity when combined with nanoparticles. PST-Dox nanoparticles were prepared via conjugation of doxorubicin to galactoxyloglucan polysaccharide (PST001) isolated from Tamarindus indica (Ti), and by ionic gelation with tripolyphosphate (TPP). This formulation possessed superior therapeutic efficiency because of the small size and increased surface-to-volume ratio. The PST-Dox nanoparticles exhibited a pH-responsive Dox release in the acidic pH of 4.5, favoring as high as 90% Dox release in a sustainable manner. PST-Dox was characterized and evaluated for its in vitro and in vivo anticancer effects. Surprisingly, this nanoparticle formulation retained the cytotoxic effects of PST001 even at lower concentrations. In vitro studies confirmed the selective cytotoxicity of PST-Dox in cancer cells through the induction of apoptosis. In vivo toxicity studies demonstrated a lower LD50 for Dox and a higher LD50 for the PST-Dox. Evaluation of the biochemical, hematological and histopathological parameters in mice supported the safety and efficacy of this formulation compared to Dox. Biodistribution data substantiated the tumor-specific delivery of these particles. Although prospective studies are warranted, in a complex disease such as cancer, cell-selective and pH-sensitive nanoparticle-based targeted drug delivery systems should be used as an effective choice over standard agents, such as doxorubicin.

A galactomannan polysaccharide from Punica granatum imparts in vitro and in vivo anticancer activity.

Galactomannan polysaccharide (PSP001) was isolated from the fruit rind of Punica granatum and was previously reported to have excellent antioxidant and immunomodulatory properties. The cytotoxicity of PSP001 was evaluated in the human cancer cell lines A375, HCT116, and HepG2 as well as the murine cancer cell lines DLA and EAC over a wide range of concentrations. PSP001 exhibited significant cytotoxicity against cancer cells through the induction of apoptosis with no in vivo toxicity up to a concentration of 2000 mg/kg body weight when assessed in BALB/c mice. The antitumor efficacy of PSP001 was tested in DLA and EAC murine ascites and EAC solid tumor mouse models. PSP001 alone and in combination with doxorubicin produced a significant reduction in the tumor burden and increased life span in both models compared to the controls. The results suggest that PSP001 has the potential to be developed as an anticancer agent either alone or as an adjuvant to chemotherapy.

A polyherbal ayurvedic drug--Indukantha Ghritha as an adjuvant to cancer chemotherapy via immunomodulation.

Indukantha Ghritha (IG) is a polyherbal preparation consisting of 17 plant components widely prescribed by ayurvedic physicians for various ailments. Though it is a known ayurvedic drug, no attempt has been made to scientifically validate its mechanism of action. Preliminary studies in our laboratory showed IG to possess considerable immunomodulatory effects with a Th1 type of immune response. In this regard, we attempted to elucidate its role as an adjuvant to cancer chemotherapy. BALB/c mice were administered IG, for a period of 14 days and parameters such as Hb, total and differential WBC count, bone marrow cellularity, lymphocyte proliferation and function, macrophage phagocytosis and tumor remission were studied. Administration of IG could inhibit tumor development in mice challenged with Dalton's lymphoma ascites. IG-induced leukopoiesis and enhanced median survival time as well as life span in tumor bearing animals. Macrophage phagocytic capacity was also elevated. Flow cytometric analysis of lymphocyte subsets and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium salt] assay for lymphocyte proliferation, yielded promising results which reinforces its use as an adjuvant to cancer chemotherapy. The polyherbal drug could reverse cyclophosphamide-induced myelosuppression in control tumor bearing animals significantly to values near or above normal levels. These results demonstrate the potential of IG, especially in several immunosuppressed conditions and patients suffering from leukopenia as a consequence of cancer chemotherapy.