Summary The inhibitory effect of c-myb antisense oligodeoxynucleotides (ODNs) conjugated to folic acid (FA) on HL-60 cell proliferation was examined. Folic acid was covalently linked to a polylysine chain and purified by gel chromatography. Sterile FA-polylysine was complexed with c-myb sense and antisense. Exposure of HL-60 cells to the FA-polylysine-c-myb antisense ODN complex resulted in a down-regulation of c-myb expression and a greater inhibition of proliferation than that obtained using free ODNs. Moreover, FA-polylysine conjugate alone or complexed to c-myb sense ODN was not toxic to cells. The antigenic properties and uptake of the vitamin were not affected by the polylysine chain. These data suggest that this strategy is potentially useful for the selective delivery of anti-oncogene-targeted ODNs into cancer cells.Antisense oligodeoxynucleotides (ODNs) have proven useful for selective inhibition of gene expression (Holt et al., 1988; Szczylik et al, 1991). However, their rate of cellular uptake appears to be quite slow, and consequently attempts have been made to enhance their stability and their delivery into cells. For instance, receptor-mediated endocytosis has been used to increase the uptake of synthetic ODNs and other foreign molecules such as proteins complexed to specific ligands (Wu & Wu, 1987, 1988Cotten et al., 1990;Leamon & Low, 1991;Citro et al., 1992;Manfredini et al., 1993). Since the receptors for some growth factors, vitamins and hormones are overexpressed in rapidly dividing tumour cells (Rothemberg & Da Costa, 1971;Asok et al., 1981;Sclhub & Franklin, 1984; Lacey et al., 1989), the ligands of these receptors can be exploited to selectively introduce therapeutic compounds into the cells. The use of modified ligands for specific cell-surface receptors as carriers of oncogene-targeted antisense ODNs represents a potentially useful therapy to be used alone or in combination with antineoplastic drugs.We have previously reported that a c-myb antisensetransferrin-polylysine complex produces an enhanced uptake into HL-60 cells, resulting in an increased biological effect. Recently, we have also observed that a polylysine chain covalently linked to compounds such as insulin, folic acid, retinoic acid, oestrone and testosterone can be used for specific interactions with nucleic acids in physiological ionic conditions (G. Citro, unpublished observation). The presented study describes the efficacy of folic acid receptor-targeted c-myb antisense in the HL-60 cell line. The effect of the complexed phosphodiester (PO) ODNs was compared with that of phosphorothioate (PS) ODN antisense given alone.With doses of 20 and 30 fig mlVl, we found that PS c-myb antisense actively inhibited the rate of the cell proliferation while free PO c-myb antisense had no effect. However, when free PO c-myb antisense ODNs were complexed to FApolylysine, their inhibitory effect on the cell proliferation was even greater than that obtained using the free PS oligos. Furthermore, whereas recent research has indicated there...

The role of spirituality on the psychological health was mostly investigated through studies conducted in terminally ill patients. However, there are not studies investigating the role of religious and spiritual beliefs on psychological state and on burden dimensions in caregivers. The purpose of this study was to investigate the association between spirituality, burden, and psychological state in caregivers of terminally ill cancer patients. Two hundred caregivers of terminally ill patients with cancer were interviewed using Prolonged Grief Disorder 12 (PG-12), Hamilton Anxiety Rating Scale (HAM-A), Hamilton Depression Scale (HAM-D), Caregiver Burden Inventory (CBI) and System of Belief Inventory (SBI-15R). The caregiver burden was positively correlated with anxiety, depression and PG-12 scores. The intrinsic spirituality was a significant predictor of the time-dependence burden (positively associated); and of the emotional burden (negatively associated). In caregivers of terminally ill cancer patients, higher levels of intrinsic spirituality predicted a higher amount of time devote to caregiving, and also protected against the emotional distress linked to providing assistance.

In terminally ill patients with cancer, the levels of depression and anxiety were lower in patients aware of their own illness state. Moreover, higher levels of extrinsic and lower levels of intrinsic spirituality predicted the awareness of one's own illness state.

The toxicity of two conjugates containing ribosome-inactivating proteins (RIPs, i.e. saporin and ricin-A chain x-linked to transferrin) has been measured on a prostatic cancer line (PC3) naturally overexpressing the transferrin receptor, in the presence of monensin and chloroquine. This paper investigates whether the increased toxicity of Tf-RIPs induced by monensin and chloroquine may be due to alterations of the normal endocytotic pathway of the complexes mediated by the transferrin receptor. Monensin, besides inducing alkalinization of normally acid intracellular compartments, causes an accumulation of the receptor-bound Tf-RIP in a perinuclear region contiguous to the cisternae of the trans-Golgi network. Chloroquine, though increasing the intracellular pH, seems not to modify the endocytotic pathway of these chimeric molecules. We believe that the enhanced toxicity of the Tf-RIPs may be related to intracellular alkalinization (i.e., endosomal or lysosomal pH) rather than to the effects on the recycling of transferrin receptor-bound toxins. We conclude that the efficacy of chimeric toxins may be modulated not only by the carrier used for their engineering but also by addition of drugs able to influence the stability and activation of the toxins inside the cell.

The lack of efficient and specific delivery to target cells still limits the potential application of antisense oligodeoxynucleotides as therapeutic agents in cancer disease. We have covalently linked a polylysine chain (10,000-20,000 mw) to compounds as folic acid, retinoic acid, transferrin, insulin and estradiol, to deliver c-myb antisense oligonucleotide into tumor cells. Using these complexes as carriers for the oligodeoxynucleotides can be achieved an increase in their uptake into target cells through a natural endocytosis pathway.