saquinavir and Neoplasms

Saquinavir was the first protease inhibitor developed for HIV therapy, and it changed the standard of treatment for this disease to a combination of drugs that ultimately led to increased survival of this otherwise deadly condition. Inhibiting the HIV protease impedes the virus from maturing and replicating. With this in mind, since the start of the COVID-19 outbreak, the research for already approved drugs (mainly antivirals) to repurpose for treatment of this disease has increased. Among the drugs tested, saquinavir showed promise in silico and in vitro in the inhibition of the SARS-CoV-2 main protease (3CLpro). Another field for saquinavir repurposing has been in anticancer treatment, in which it has shown effects in vitro and in vivo in several types of cancer, from Kaposi carcinoma to neuroblastoma, demonstrating cytotoxicity, apoptosis, inhibition of cell invasion, and improvement of radiosensibility of cancer cells. Despite the lack of follow-up in clinical trials for cancer use, there has been a renewed interest in this drug recently due to COVID-19, which shows similar pharmacological pathways and has developed superior in silico models that can be translated to oncologic research. This could help further testing and future approval of saquinavir repurposing for cancer treatment.

Topics: COVID-19 Drug Treatment; HIV Infections; HIV Protease Inhibitors; Humans; Neoplasms; Saquinavir; SARS-CoV-2

The possible use of HIV protease inhibitors (HIV-PI) as new therapeutic option for the treatment of cancer primarily originated from their success in treating HIV-related Kaposi's sarcoma (KS). While these findings were initially attributed to immune reconstitution and better control of oncogenic viral infections, the number of reports on solid tumors, KS, lymphoma, fibrosarcoma, multiple myeloma and prostate cancer suggest other mechanisms for the anti-neoplastic activity of PIs. However, a major drawback for the possible adoption of HIV-PIs in the therapy of cancer relies on their relatively weak anticancer potency and important side effects. This has propelled several groups to generate derivatives of HIV-PIs for anticancer use, through modifications such as attachment of different moieties, ligands and transporters, including saquinavir-loaded folic acid conjugated nanoparticles and nitric oxide (NO) derivatives of HIV-PIs. In this article, we discuss the current preclinical and clinical evidences for the potential use of HIV-PIs, and of novel derivatives, such as saquinavir-NO in the treatment of cancer.

Topics: Antiretroviral Therapy, Highly Active; HIV Infections; HIV Protease Inhibitors; HIV-1; Humans; Neoplasms; Nitric Oxide; Saquinavir; Sarcoma, Kaposi

Development of resistance to TRAIL-induced toxicity is one of the strategies used from tumor cells to escape destruction from the immune system. This process may occur through aberrant expression of functional receptors, overexpression of decoy receptors on tumor cell membrane, or malfunctioning of downstream signals triggered by specific ligation of TRAIL. Numerous cytostatic, but also noncytostatic, drugs like protease inhibitors and NO-hybridized molecules have been shown to revert sensitivity of neoplastic cells to TRAIL by means of different mechanisms. This paper will review the possible routes of reconstitution of sensitivity to TRAIL-mediated immune response by specific modulation of different signals responsible for the development of resistance at both the membrane and the intracellular levels. Moreover, we will review and suggest novel strategies, aimed at resetting immune cell efficiency in cancer treatment.

Topics: Animals; Apoptosis; Humans; Neoplasms; Receptors, TNF-Related Apoptosis-Inducing Ligand; Saquinavir; Signal Transduction; TNF-Related Apoptosis-Inducing Ligand; Tumor Escape

The use of anti-HIV drugs as cancer treatments is not new. Azidothymidine was studied as an antineoplastic in the 1990s, but despite promising in vitro data, clinical trials showed little antitumour activity. HIV protease inhibitors were developed in the early 1990s, and their subsequent incorporation into highly active antiretroviral therapy (HAART) has profoundly changed the natural history of HIV infection. The potential antitumour properties of these drugs have been investigated because of their success in treating HIV-related Kaposi's sarcoma. HAART's effects on Kaposi's sarcoma did not always correlate with immune reconstitution, and activity against other solid and haematological malignancies has been established. Inhibition of tumour-cell invasion and angiogenesis were properties first ascribed to inhibition of HIV protease; however, they have pleiotropic antitumour effects, including inhibition of inflammatory cytokine production, proteasome activity, cell proliferation and survival, and induction of apoptosis. HIV protease inhibitors are thus a new class of anticancer drugs with multiple effects, and other anti-HIV drugs might hold similar promise.

Topics: Anti-HIV Agents; Antiretroviral Therapy, Highly Active; Cidofovir; Cytosine; HIV Protease Inhibitors; Humans; Indinavir; Nelfinavir; Neoplasms; Organophosphonates; Receptors, CXCR4; Reverse Transcriptase Inhibitors; Ritonavir; Saquinavir; Zidovudine

Topics: Anti-HIV Agents; Cell Transformation, Neoplastic; HIV Protease Inhibitors; Humans; Indinavir; Neoplasms; Rheumatic Diseases; Ritonavir; Saquinavir

Potential differences in pharmacokinetics (PK) between healthy subjects and patients with cancer were investigated using a physiologically based pharmacokinetic approach integrating demographic and physiological data from patients with cancer. Demographic data such as age, sex and body weight, and clinical laboratory measurements such as albumin, alpha-1 acid glycoprotein (AAG) and hematocrit were collected in ~2500 patients with cancer. A custom oncology population profile was built using the observed relationships among demographic variables and laboratory measurements in Simcyp® software, a population based ADME simulator. Patients with cancer were older compared with the age distribution in a built-in healthy volunteer profile in Simcyp. Hematocrit and albumin levels were lower and AAG levels were higher in patients with cancer. The custom population profile was used to investigate the disease effect on the pharmacokinetics of two probe substrates, saquinavir and midazolam. Higher saquinavir exposure was predicted in patients relative to healthy subjects, which was explained by the altered drug binding due to elevated AAG levels in patients with cancer. Consistent with historical clinical data, similar midazolam exposure was predicted in patients and healthy subjects, supporting the hypothesis that the CYP3A activity is not altered in patients with cancer. These results suggest that the custom oncology population profile is a promising tool for the prediction of PK in patients with cancer. Further evaluation and extension of this population profile with more compounds and more data will be needed.

Topics: Adult; Aged; Aged, 80 and over; Anti-Anxiety Agents; Body Mass Index; Body Size; Body Weight; Female; Hematocrit; HIV Protease Inhibitors; Humans; Male; Midazolam; Middle Aged; Models, Biological; Neoplasms; Orosomucoid; Saquinavir; Serum Albumin; Young Adult

Human immunodeficiency virus protease inhibitors (HIV-PIs), such as indinavir and saquinavir, have been shown to block angiogenesis and tumor cell invasion and to induce tumor cell apoptosis and growth arrest, respectively, both in vitro and in vivo. These findings have suggested that HIV-PIs or their analogues can be used as antitumor drugs. To this regard, indinavir and saquinavir were assessed for their ability to inhibit in vivo the growth of highly prevalent human tumors, such as lung, breast, colon and hepatic adenocarcinomas. We show here that both HIV-PIs significantly inhibited the growth of all adenocarcinomas tested in the mice model. This was not mediated by effects on proteasome-dependent cell growth arrest or on apoptosis but by the block of angiogenesis and matrix metalloproteinase activity. Accordingly, therapeutic steadystate concentrations of indinavir or saquinavir were highly effective in inhibiting invasion of tumor cells in vitro. In contrast, growth arrest was induced only by high concentrations of saquinavir that are not reached or are only transiently present in plasma of treated patients, likely through a proteasome-mediated mechanism. These data suggest that HIV-PIs or their analogues, characterized by a better biodistribution and lower toxicity, may represent a new class of antitumor drugs capable of targeting both matrix metalloproteinases and the proteasome for a most effective antitumor therapy.

Topics: Animals; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Female; HIV Protease Inhibitors; Humans; Immunohistochemistry; Indinavir; Matrix Metalloproteinase 2; Matrix Metalloproteinase Inhibitors; Matrix Metalloproteinases; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasms; Neovascularization, Pathologic; Proteasome Endopeptidase Complex; Saquinavir; Tumor Burden; Xenograft Model Antitumor Assays

Topics: Animals; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; HIV Protease Inhibitors; Humans; Immunohistochemistry; Indinavir; Matrix Metalloproteinase 2; Matrix Metalloproteinase Inhibitors; Mice; Neoplasms; Neovascularization, Pathologic; Saquinavir; Xenograft Model Antitumor Assays

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cisplatin; Doxorubicin; Humans; Mice; Neoplasms; Nitric Oxide; Nitric Oxide Synthase Type III; Saquinavir

Application of the HIV protease inhibitor saquinavir (Saq) to cancer chemotherapy is limited by its numerous side effects. To overcome this toxicity, we modified the original compound by covalently attaching a nitric oxide (NO) group. We compared the efficacy of the parental and NO-modified drugs in vitro and in vivo. The novel compound saquinavir-NO (Saq-NO) significantly reduced the viability of a wide spectrum of human and rodent tumor cell lines at significantly lower concentration than the unmodified drug. In contrast to Saq, Saq-NO had no effect on the viability of primary cells and drastically reduced B16 melanoma growth in syngeneic C57BL/6 mice. In addition, at the equivalent of the 100% lethal dose of Saq, Saq-NO treatment caused no apparent signs of toxicity. Saq-NO blocked the proliferation of C6 and B16 cells, up-regulated p53 expression, and promoted the differentiation of these two cell types into oligodendrocytes or Schwann-like cells, respectively. Although it has been well documented that Saq decreases tumor cell viability by inhibiting Akt, the anticancer properties of Saq-NO were completely independent of the phosphatidylinositol 3-kinase/Akt signaling pathway. Moreover, Saq-NO transiently up-regulated Akt phosphorylation, delivering a protective signal that could be relevant for primary cell protection and the absence of drug toxicity in vivo. It was unlikely that released NO was independently responsible for these drug effects because Saq-NO treatment increased intracellular and secreted NO levels only slightly. Rather, the chemical modification seems to have produced a qualitatively new chemical entity, which may have a unique mode of action against cancer cells.

Topics: Animals; Antineoplastic Agents; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Cytostatic Agents; Drug Synergism; Humans; Mice; Mice, Inbred C57BL; Neoplasms; Nitric Oxide; Oncogene Protein v-akt; Proto-Oncogene Proteins c-akt; Rats; Saquinavir; Signal Transduction

The ATP binding cassette (ABC)-transporters are energy dependent efflux pumps which regulate the pharmacokinetics of both anti-cancer chemotherapeutic agents, e.g. taxol, and of human immunodeficiency virus-1 (HIV-1) protease inhibitors (HPIs), e.g. saquinavir. Increased expression of several ABC-transporters, especially P-glycoprotein (P-gp) and multidrug resistance protein 2 (MRP2), are observed in multidrug resistant (MDR) tumor cells and on HIV-1 infected lymphocytes. In addition, due to their apical expression on vascular endothelial barriers, both P-gp and MRP2 are of crucial importance towards dictating drug access into sequestered tissues. However, although a number of P-gp inhibitors are currently in clinical trials, possible inhibitors of MRP2 are not being thoroughly investigated. The experimental leukotriene receptor antagonist (LTRA), MK-571 is known to be a potent inhibitor of MRP transporters. Using the MRP2 over-expressing Madin-Darby canine kidney cell line, MDCKII-MRP2, we evaluated whether the clinically approved LTRAs, e.g. montelukast (Singulair) and zafirlukast (Accolate), can similarly suppress MRP2-mediated efflux. We compared the efficacy of increasing concentrations (20-100 microM) of MK-571, montelukast, and zafirlukast, in suppressing the efflux of calcein-AM, a fluorescent MRP substrate, and the radiolabeled [(3)H-] drugs, taxol and saquinavir. Montelukast was the most potent inhibitor (p<0.01) of MRP2-mediated efflux of all three substrates. Montelukast also increased (p<0.01) the duration of intracellular retention of both taxol and saquinavir. More than 50% of the drugs were retained in cells even after 90 min post removal of montelukast from the medium. Our findings implicate that montelukast, a relatively safe anti-asthmatic agent, may be used as an adjunct therapy to suppress the efflux of taxol and saquinavir from MRP2 overexpressing cells.

Topics: Acetates; Animals; Anti-Asthmatic Agents; Antineoplastic Agents, Phytogenic; Biological Transport; Cell Line; Chemotherapy, Adjuvant; Cyclopropanes; Dogs; Drug Resistance, Neoplasm; Drug Resistance, Viral; Fluoresceins; HIV Infections; HIV Protease Inhibitors; Indoles; Leukotriene Antagonists; Multidrug Resistance-Associated Proteins; Neoplasms; Paclitaxel; Phenylcarbamates; Propionates; Quinolines; Saquinavir; Sulfides; Sulfonamides; Time Factors; Tosyl Compounds