Neem (Azadirachta indica), a member of the Meliaceae family, is a fast growing tropical evergreen tree with a highly branched and stout, solid stem. Because of its tremendous therapeutic, domestic, agricultural and ethnomedicinal significance, and its proximity with human culture and civilization, neem has been called "the wonder tree" and "nature's drug store." All parts of this tree, particularly the leaves, bark, seed-oil and their purified products are widely used for treatment of cancer. Over 60 different types of biochemicals including terpenoids and steroids have been purified from this plant. Pre-clinical research work done during the last decade has fine-tuned our understanding of the anticancer properties of the crude and purified products from this plant. The anticancer properties of the plant have been studied largely in terms of its preventive, protective, tumor-suppressive, immunomodulatory and apoptotic effects against various types of cancer and their molecular mechanisms. This review aims at scanning scattered literature on "the anticancer biology of A. indica," related toxicity problems and future perspectives. The cogent data on the anticancer biology of products from A. indica deserve multi-institutional clinical trials as early as possible. The prospects of relatively cheaper cancer drugs could then be brighter, particularly for the under-privileged cancer patients of the world.

Besides mass drug administration, successful elimination of human lymphatic filariasis, a mosquitoborne tropical parasitic disease, requires developing other suitable prophylactic agents such as vaccines. The Brugia malayi abundant larval transcript-2 (BmALT-2) protein has been identified as one possible candidate. So far, it (E-ALT-2) has been expressed as a 24-kDa non-glycosylated protein in Escherichia coli. Easy and low-cost downstream purification of secreted BmALT-2 in Pichia pastoris may be a vital option to inexpensive large-scale production. This study focused on expression and molecular characterization of BmALT-2 (P-ALT-2) in P. pastoris. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis showed that some P. pastoris colonies produced 27 and 24 kDa bands and few colonies produced a 24-kDa band. Preliminary studies confirmed glycosylation of 27 kDa P-ALT-2. The ratio of glycosylated and non-glycosylated P-ALT-2 was 20:80-70:30 in various colonies. The maximum yield of glycosylated and non-glycosylated P-ALT-2 was measured as 7.99 § 1.12 and 9.18 § 1.35 mg L ¡1 compared to 6.5 § 1.2 mg L ¡1 of E-ALT-2 in shake flasks. Their overall expression was about 25% and 35% higher than that in E. coli. The glycosylated P-ALT-2 exhibited about 15% higher immunoreactivity with human endemic normal sera. The enhanced secreted production by P. pastoris may lead to cost-effective large-scale production of BmALT-2.

Persea americana is much sought after both for the nutritional value of its fruit and the medicinal values of its various plant parts. A chromosomal aberration assay was undertaken to evaluate the potential genotoxicity of crude extracts from avocado fruits and leaves. Chromosomal aberrations were observed in cultured human peripheral lymphocytes exposed to separately increasing concentrations of 50% methanolic extracts of Persea americana fruit and leaves. The groups exposed to leaf and fruit extracts, respectively, showed a concentration-dependent increase in chromosomal aberrations as compared to that in a control group. The mean percentage total aberrant metaphases at 100 mg/kg, 200 mg/kg, and 300 mg/kg concentrations of leaf extract were found respectively to be 58 ± 7.05, 72 ± 6.41, and 78 ± 5.98, which were significantly higher (p < 0.0001 each) than that in the control group (6 ± 3.39). The mean percentage total aberrant metaphases at 100 mg/kg, 200 mg/kg, and 300 mg/kg concentrations of fruit extract were found to be 18 ± 5.49, 40 ± 10.00, and 52 ± 10.20, respectively, which were significantly higher (p = 0.033, p < 0.0001, and p < 0.0001, respectively) than that for control (6 ± 3.39). Acrocentric associations and premature centromeric separation were the two most common abnormalities observed in both the exposed groups. The group exposed to leaf extracts also showed a significant number of a variety of other structural aberrations, including breaks, fragments, dicentrics, terminal deletion, minutes, and Robertsonian translocations. The group exposed to leaf extract showed higher frequency of all types of aberrations at equal concentrations as compared to the group exposed to fruit extract.

Human lymphatic filariasis, a mosquito-borne neglected tropical parasitic disease, needs an early development of prophylactic agents such as a vaccine for its successful elimination. Our earlier study suggested the enhanced immunological response by fusion protein (P-TUFT-ALT-2) of Tuftsin and ALT-2 in a mice model. We cultured human peripheral blood mononuclear cells (PBMCs) and treated cells with Escherichia coli-expressed ALT-2 (E-ALT-2) and P-TUFT-ALT-2. Real-time polymerase chain reaction was performed to identify the mRNA copy number of various cytokine and transcription factor genes. The recombinant vaccine candidate was also validated for humans by immunoreactivity with human sera samples of natural infection. In this study, P-TUFT-ALT-2 stimulated 12% higher PBMC proliferation in endemic normal (EN) individuals than E-ALT-2 alone. There was enhanced production of IFN γ, IL-2, IL-5 and IL-12, indicating a balanced Th1/Th2 response. However, higher expression of IL-5 and lower IL-4 validate the humoral response through an IL-5-dependent manner. Also, high level of IL-17 indicates a strong Th/Treg regulation over T-cell activation. The upregulated T-bet might have enhanced IFN-γ production, whereas GATA-3 was supposed to enhance IL-5 expression. The fusion protein also exhibited 15–16% higher reactivity with EN clinical sera, exposing the upregulation of IgG1 and IgM in natural infection. The higher reactivity of P-TUFT-ALT-2 with sera of natural infection (EN) was validated indirectly by B-cell activation through various cytokines and regulatory genes produced from different T cells. Thus, these findings endorse P-TUFT-ALT-2 as a potential vaccine candidate for human lymphatic filariasis.