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Nathan Goodyear

Oncotarget | Preclinical evaluation of a nanoformulated antihelminthic, niclosamide, in... - 0 views

  • Ovarian cancer is the most lethal gynecologic malignancy in the world
  • paclitaxel represents a breakthrough in the treatment of ovarian cancer, the overall 5-year survival rate of patients with stage III disease is still approximately 40%
  • Targeting cancer stem cells is an emerging concept in cancer therapy
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  • Ovarian cancer stem cells play an important role in chemoresistance and cancer recurrence
  • Furthermore, recent studies indicate that niclosamide exhibits anticancer effects against various human cancer cells by acting on multiple cell signaling pathways and inducing mitochondrial uncoupling [16–21]
  • This toxicity evaluation showed that oral nano-NI had no toxic effect on either group of mice in terms of weight, plasma albumin levels, and blood cell counts, and revealed no adverse effects on vital organ function in the rodents, which suggests that nano-NI is safe for animals
  • The nano-NI demonstrated significantly higher inhibitory effects on sphere formation than the original niclosamide did
  • the nano-NI formulation decreased the metabolic activity of ovarian cancer cells and caused a metabolic shift from oxidative phosphorylation to glycolysis
  • has low systemic bioavailability (~10%) when administered orally, which is beneficial for treating local parasitic infections of the intestines while minimizing systemic exposure
  • niclosamide inhibits tumor cell growth by interrupting multiple pathways (Wnt, Notch, STAT3, NF-κB, and mTORc1) and the generation of reactive oxygen species in several cancer cells
  • The current standard therapy for ovarian cancer includes taxanes and platinum-based chemotherapy after cytoreductive surgery. Among treated patients, nearly 70 to 80% will experience disease recurrence
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    nano-Niclosamide more effective than traditional Niclosamide in in vitro and in vivo ovarian cancer.
Nathan Goodyear

Promising role for Gc-MAF in cancer immunotherapy: from bench to bedside - 0 views

  • MAF precursor activity has also been lost or reduced after Gc-globulin treatment in some cancer cell lines
  • This appears to result from the deglycosylated ɑ-N-acetylgalactosaminidase (nagalase) secreted from cancerous cells
  • Nagalase has been detected in many cancer patients, but not in healthy individuals
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  • Studies have shown that the production of nagalase has a mutual relationship with Gc-MAF level and immunosuppression
  • It has been demonstrated that serum levels of nagalase are good prognosticators of some types of cancer
  • The nagalase level in serum correlates with tumor burden and it has been shown that Gc-MAF therapy progresses, nagalase activity decreases
  • It has been shown that Gc-MAF can inhibit the angiogenesis induced by pro-inflammatory prostaglandin E1
  • The effect of Gc-MAF on chemotaxis or activation of tumoricidal macrophages is likely the main mechanism against angiogenesis.
  • Administration of Gc-MAF stimulates immune-cell progenitors for extensive mitogenesis, activates macrophages and produces antibodies. “This indicates that Gc-MAF is a powerful adjuvant for immunization.”
  • Cancer cell lines do not develop into tumor genes in mouse models after Gc-MAF-primed immunization (29-31) and the effect of Gc-MAF has been approved for macrophage stimulation for angiogenesis, proliferation, migration and metastatic inhibition on tumors induced by MCF-7 human breast cancer cell line
  • The protocol included: "a high dose of second-generation Gc-MAF (0.5 ml) administered twice a week intramuscularly for a total of 21 injections.”
  • Yamamoto et al. showed that the administration of Gc-MAF to 16 patients with prostate cancer led to improvements in all patients without recurrence
  • Inui et al. reported that a 74-year-old man diagnosed with prostate cancer with multiple bone metastases was in complete remission nine months after initiation of GcMAF therapy simultaneously with hyper T/NK cell, high-dose vitamin C and alpha lipoic acid therapy
  • It has also been approved for non-neoplastic diseases such as autism (41), multiple sclerosis (42, 43), chronic fatigue syndrome (CFS) (40), juvenile osteoporosis (44) and systemic lupus erythematous (45).
  • Gc-MAF has been verified for use in colon, thyroid (38), lung (39), liver, thymus (36), pancreatic (40), bladder and ovarian cancer and tongue squamous carcinoma
  • Prostate, breast, colon, liver, stomach, lung (including mesothelioma), kidney, bladder, uterus, ovarian, head/neck and brain cancers, fibrosarcomas and melanomas are the types of cancer tested thus far
  • weekly administration of 100 ng Gc-MAF to cancer at different stages and types showed curative effects at different follow-up times
  • this treatment has been suggested for non-anemic patients
  • Studies have shown that weekly administration of 100 ng Gc-MAF to cancer patients had curative effects on a variety of cancers
  • Because the half-life of the activated macrophages is approximately one week, it must be administered weekly
  • In vivo weekly intramuscular administration of Gc-MAF (100 ng) for 16-22 weeks was used to treat patients with breast cancer
  • individuals harboring different VDR genotypes had different responses to Gc-MAF and that some genotypes were more responsive than others
  • Administration of Gc-MAF for cancer patients exclusively activates macrophages as an important cell in adaptive immunity
  • Gc-MAF supports humoral immunity by producing, developing and releasing large quantities of antibodies against cancer. Clinical evidence from a human model of breast cancer patients supports this hypothesis
  • There is also evidence that confirms the tumoricidal role of Gc-MAF via Fc-receptor mediation
  • It is likely that the best therapeutic responses will be observed when the nutritional and inflammatory aspects are taken together with stimulation of the immune system
  • it should be noted that no harmful side effects of Gc-MAF treatment have been reported, even when it was successfully administered to autistic children
  • The natural activation mechanism of macrophages by Gc-MAF is so natural and it should not have any side effects on humans or animal models even in cell culture
  • Besides the Gc-MAF efficacy on macrophage activity, it can be a potential anti-angiogenic agent (28) and an inhibitor of the migration of cancerous cells in the absence of macrophages (47).
  • Activating or modifying natural killer cells, dendritic cells, DC, CTL, INF and IL-2 have all been recommended for cancer immunotherapy
  • It has been reported that nagalase cannot deglycosylate Gc-MAF as it has specificity for Gc globulin alone
  • inflammation-derived macrophage activation with the participation of B and T lymphocytes is the main mechanism
  • macrophages highly-activated by the addition of Gc-MAF can show tumoricidal activity
  • Previous clinical investigations have confirmed the efficacy of Gc-MAF. In addition to activating existing macrophages, Gc-MAF is a potent mitogenic factor that can stimulate the myeloid progenitor cells to increase systemic macrophage cell counts by 40-fold in four days
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    great review on Gc-MAF in cancer.  An increase in nagalase blocks Gc-protein to Gc-MAF activity leaving the host immune system compromised.
Nathan Goodyear

Ivermectin: enigmatic multifaceted 'wonder' drug continues to surprise and exceed expec... - 0 views

  • The avermectins are known to possess pronounced antitumor activity
  • Over the past few years, there have been steadily increasing reports that ivermectin may have varying uses as an anti-cancer agent, as it has been shown to exhibit both anti-cancer and anti-cancer stem cell properties
  • In human ovarian cancer and NF2 tumor cell lines, high-dose ivermectin inactivates protein kinase PAK1 and blocks PAK1-dependent growth
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  • PAK1 is essential for the growth of more than 70% of all human cancers, including breast, prostate, pancreatic, colon, gastric, lung, cervical and thyroid cancers, as well as hepatoma, glioma, melanoma, multiple myeloma and for neurofibromatosis tumors
  • Ivermectin suppresses breast cancer by activating cytostatic autophagy, disrupting cellular signaling in the process, probably by reducing PAK1 expression
  • Cancer stem cells are a key factor in cancer cells developing resistance to chemotherapies and these results indicate that a combination of chemotherapy agents plus ivermectin could potentially target and kill cancer stem cells, a paramount goal in overcoming cancer
  • Triple-negative breast cancers, which lack estrogen, progesterone and HER2 receptors, account for 10–20% of breast cancers and are associated with poor prognosis
  • Ivermectin addition led to transcriptional modulation of genes associated with epithelial–mesenchymal transition and maintenance of a cancer stem cell phenotype in triple-negative breast cancers cells, resulting in impairment of clonogenic self-renewal in vitro and inhibition of tumor growth and metastasis in vivo
  • ivermectin synergizes with the chemotherapy agents cytarabine and daunorubicin to induce cell death in leukemia cells
  • Ivermectin-induced cytostatic autophagy also leads to suppression of tumor growth in breast cancer xenografts, causing researchers to believe there is scope for using ivermectin to inhibit breast cancer cell proliferation and that the drug is a potential treatment for breast cancer
  • Ivermectin inhibits proliferation and increases apoptosis of various human cancers
  • Activation of WNT-TCF signaling is implicated in multiple diseases, including cancers of the lungs and intestine,
  • A new screening system has found that ivermectin inhibits the expression of WNT-TCF targets
  • It represses the levels of C-terminal β-catenin phosphoforms and of cyclin D1 in an okadaic acid-sensitive manner, indicating its action involves protein phosphatases
  • In vivo, ivermectin selectively inhibits TCF-dependent, but not TCF-independent, xenograft growth without side effects
  • ivermectin has an exemplary safety record, it could swiftly become a useful tool as a WNT-TCF pathway response blocker to treat WNT-TCF-dependent diseases, encompassing multiple cancers.117
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    Ivermectin shows promise and usefullness in several cancer types.  This is a review article.
Nathan Goodyear

Targeting estrogen receptor subtypes (ERα and ERβ) with selective ER modulato... - 0 views

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    Studies in breast cancer and prostate cancer have revealed different effects by ER alpha vs ER beta.  It is no surprise that the same effects are found in ovarian cancer.  This study found ER alpha antagonists and ER beta agonists "significantly" suppressed growth in the ovarian cancer cell lines SKOV3 and OV2008.  Also, ER alpha agonist and ER beta antagonist "significantly" increased growth in the same cell lines.  These findings point to in increased proliferation with ER alpha and decreased with ER beta.  This is consistent with breast and prostate cancer also.
Nathan Goodyear

Growth Inhibition of Ovarian Tumor-Initiating Cells by Niclosamide | Molecular Cancer T... - 0 views

  • Ovarian cancer is the most lethal gynecologic malignancy and the fifth-most cause of overall cancer death of women in developed countries
  • An increasingly accepted cancer stem cell hypothesis regards tumors as caricatures of normal organs, possessing a hierarchy of cell types, at various stages of aberrant differentiation, descended from precursor tumor-initiating cells (TIC) cells that are highly resistant to conventional cytotoxics
  • Significant changes of gene expression in 2,928 genes were identified after niclosamide treatment for different time periods
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  • uncoupling of mitochondrial oxidative phosphorylation is believed to be its anti-helminthic mechanism of action
  • we hypothesized that niclosamides antagonistic effects on OTICs could, in part, be due to its disruption of metabolism
  • Our results showed that genes participating in protein complexes of oxidative phosphorylation were downregulated
  • niclosamide treatment resulted in a more than 20% increase in reactive oxygen species (ROS) in cultured OTICs
  • niclosamide, which has proved to be safe and effective for the past 2 decades against numerous parasites, inhibited OTIC growth both in vitro and in vivo
  • niclosamide represses metabolic enzymes responsible for bioenergetics, biosynthesis, and redox regulation specifically in OTICs, presumably leading to mitochondrial intrinsic apoptosis pathways, loss of tumor stemness, and growth inhibition
  • Niclosamide is believed to inhibit mitochondrial oxidative phosphorylation
  • Niclosamide was reported to inactivate NF-κB, causing mitochondrial damage and the generation of ROS, leading to apoptosis of leukemic stem cells
  • niclosamide were identified in a screen for mTOR-signaling inhibitors
  • mTOR was reported to maintain stemness properties of HSCs by inhibiting mitochondrial biogenesis and ROS levels (39), implying that mTOR inhibitors (such as niclosamide) may interfere with mitochondria and various metabolic pathways in TICs via disruption of antioxidant responses
  • We observed Wnt hyperactivity in OTICs, in agreement with previous hypotheses of Wnt inhibitor effectiveness as an ovarian cancer therapy
  • niclosamide has now been independently identified in screens for Wnt inhibitors
  • downregulation of the Wnt/β-catenin target oncogenes survivin and c-Myc
  • ovarian carcinogenesis, the cell-to-cell signaling pathway Notch (8), were also suppressed by niclosamide (data not shown). These results agree with another recent niclosamide study in leukemia (49), and it has been widely hypothesized that disruption of Notch signaling may represent a highly effective therapy for ovarian and other solid tumors, via its essentiality to maintaining TIC stemness
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    Niclosamide, common anti-parasitic medication, inhibits cellular metabolism and increases ROS; both of which provide powerful anti-proliferative, anti-cancer treatment mechanism in TICs. Powerful target therapy for cancer stem cells. Also shown to inhibit Wnt stimulated oncogenes survivin and c-Myc, disrupts Notch signaling, inactivates NF-kappaBeta, and inhibits mTOR-signaling.  This has been found in in vitro and in vivo studies.
Nathan Goodyear

Cancers | Free Full-Text | A Second WNT for Old Drugs: Drug Repositioning against WNT-D... - 0 views

  • To date nearly half of known human tumors show a dysregulation of the WNT signaling pathway
  • It should be also noted that the WNT pathway is not exclusively employed during development or overactivated in cancer. In adults many healthy tissues rely on it for renewal and homeostasis maintenance, most notably the intestine, haematopoietic system, hair, bones and skin. Therefore one might expect adverse reactions in all these organ systems, which has indeed been observed for many WNT-targeting compounds upon attempts to push them into the clinics
  • The intestine seems to be the most vulnerable in this regard
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  • Ivermectin inhibits proliferation of human colon cancer and lung cancer cells both in vitro and in vivo
  • The anti-proliferative action, affecting both the bulk tumor cells and CSCs, was linked in this study to inhibition of WNT signaling
  • the anti-WNT IC50 of ivermectin is 5–10 times (~1–2 µM vs. 10 µM) lower than that of its toxic effect against chloride channels
  • oral bioavailability of the drug, as for other antiparasitic drugs discussed in this section, is very low
  • Toxicity studies in vivo have also demonstrated a wide therapeutic index for ivermectin
  • Its anti-proliferative activity has been demonstrated in a wide array of cancer cell lines representative of WNT-dependent cancers: non-small lung carcinoma [96], multiple myeloma [97], hepatoma [98], adrenocortical carcinoma [99], ovarian cancer [100] and glioblastoma
  • Niclosamide inhibits the canonical WNT pathway
  • In addition to inhibiting the canonical WNT pathway, niclosamide may mediate its anticancer activities through several other signaling pathways such as NOTCH [107], MTOR [108], NF-κB [97] and STAT3 [96]
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    review article highlights older medications that have anti-Wnt pathway effects in cancer.  Roughly, 50% of cancer involve upregulated Wnt pathway activity. Other drugs of note: metformin
Nathan Goodyear

Tumor regionalization after surgery: Roles of the tumor microenvironment and neutrophil... - 0 views

  • tumor surgery must be carefully considered because the risk of metastasis could be increased by the surgical procedure.
  • NETosis, which is the process of forming neutrophil extracellular traps (NETs)
  • surgery-induced metastasis
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  • surgery per se can promote cancer metastasis through a series of local and systemic events
  • surgery results in a serious wound that disrupts the structural barrier preventing the outspreading of cancer cells, change the properties of the cancer cells and stromal cells remaining in the tumor microenvironment, or impairs the host defense systems against cancers
    • Nathan Goodyear
       
      Key point; add to presentation on surgery and metastasis
  • After the primary tumor is surgically removed, the metastases can start to grow vigorously via neoangiogenesis because the circulating inhibitors disappear
  • infection and inflammation during the postoperative period have been reported to increase the risk of cancer recurrence in patients
  • Surgeons have long suspected that surgery, even if it is a necessary step in cancer treatment, facilitates cancer metastasis
  • Surgery-induced cancer metastasis has been well established in animal models
  • tumor cell dissemination, tumor-favoring immune responses, and neoangiogenesis
  • the surgical resection of primary tumors is beneficial is controversial
  • CTCs abruptly increase just after surgery
  • Even externally palpitating tumors for diagnosis could increase the numbers of CTCs in skin cancer and breast cancer
  • excessive glucocorticoids negatively modulate immune functions
  • immune surveillance against tumors is considered to be impaired by surgical stress
  • In addition to glucocorticoids, during stimulation of the HPA axis, the catecholamine hormones epinephrine and norepinephrine are released from the adrenal medulla
  • NK cell suppression may be attributed to increased levels of catecholamines as well as glucocorticoids
  • In mice bearing a primary tumor, it was observed that the removal of the primary tumor facilitated the growth of highly vascularized metastases
  • primary tumors may secrete angiogenic inhibitors as well as angiogenic activators
  • second phase of tumor recurrence and metastasis, which are newly acquired events, rather than just outcomes of incomplete treatment.
    • Nathan Goodyear
       
      Another key point
  • double-edged sword
  • HIF-1 in neutrophils plays a critical role in NETosis and bacteria-killing activity
  • neutrophils play various roles in the initiation and progression of cancer
  • NETosis
  • many inflammatory and neoplastic diseases
  • formation of neutrophil extracellular traps (NETs), which are large extracellular complexes composed of chromatin and cytoplasmic/granular proteins1
  • NETosis has been highlighted as an inflammatory event that promotes cancer metastasis
  • Once activated, neutrophils produce intracellular precursors by using DNA, histones, and granular and cytoplasmic proteins and then spread the mature form of NETs out around themselves
  • A series of these events is called NETosis.
  • neutrophil elastase, myeloperoxidase, cathepsin G, proteinase 3, lactoferrin, gelatinase, lysozyme C, calprotectin, neutrophil defensins, and cathelicidins
  • innate immune response against infection
  • Neutrophils are the most abundant type of granulocytes, comprising 40–70% of all white blood cells
  • two types of NEToses, suicidal (or lytic) NETosis and vital NETosis
  • Suicidal NETosis mainly depends on the production of reactive oxygen species (ROS)
  • Since neutrophils die during this process, it is called suicidal NETosis.
  • vital NETosis
  • vital NETosis occurs independently of ROS production
  • Vital NETosis can be induced by Gram-negative bacteria. LPS
  • NETs are present in a variety of cancers, such as lung cancer, colon cancer, ovarian cancer, and leukemia
  • neutrophils actively undergo NETosis in the tumor microenvironment
  • Hypoxia
  • NETosis plays a pivotal role in noninfectious autoimmune diseases,
  • cytokines
  • tumor-derived proteases
  • tumor exosomes
  • NETosis generally actively progresses in the tumor microenvironment.
  • the proliferative cytokines TGFβ and IL-10 and the angiogenic factor VEGF are representative of neutrophil-derived tissue repair proteins.
  • NETosis is a defense system to protect the body from invading pathogens
  • when neutrophils are excessively stimulated, they produce excess NETs, thereby leading to pathological consequences
  • plasma levels of NETosis markers are elevated after major surgeries
  • local invasion, intravasation into the blood or lymphatic vessels, escape from the immune system, anchoring to capillaries in target organs, extravasation into the organs, transformation from dormant cells to proliferating cells, colonization to micrometastases, and growth to macrometastases
  • NETs promote metastasis at multiple steps
  • NETs loosen the ECM and capillary wall to promote the intravasation of cancer cells
  • NETs and platelets wrap CTCs, which protects them from attack by immune cells and shearing force by blood flow
  • NETs promote the local invasion of cancer cells by degrading the extracellular matrix (ECM)
  • neutrophil elastase, matrix metalloproteinase 9, and cathepsin G
  • NETs also promote the intravasation of cancer cells
  • millions of tumor cells are released into the circulation every day,
  • NETs can wrap up CTCs with platelets
  • β1-integrin plays an important role in the interaction between CTCs and NETs
  • NET-platelet-CTC aggregates.
  • After metastasizing to distant tissues, tumor cells are often found to remain dormant for a period of time and unexpectedly regrow late
  • NETs are believed to participate in the reactivation of dormant cancer cells in metastatic regions
  • NET-associated proteases NE and MMP-9 were found to be responsible for the reactivation of dormant cancer cells
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    Surgery induced metastasis: it is real and steered by NETosis.
Nathan Goodyear

The use of antioxidants with first-line chemotherapy in two cases of ovarian cancer - 0 views

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    IV, high dose, vitamin C adjunct therapy shown to aid in the remission in to women with ovarian cancer. These two cases studies do only looked and high dose antioxidant therapy as an adjunct in ovarian cancer and they found good results.
Nathan Goodyear

In vivo loss-of-function screens identify KPNB1 as a new druggable oncogene in epitheli... - 0 views

  • we functionally validated a potent EOC oncogene, KPNB1, and showed its clinical relevance to human EOC
  • a well-established antiparasitic drug, ivermectin, has antitumor effects on EOC through its inhibition of KPNB1
  • EOC has high intertumor and intratumor heterogeneity at the molecular and epigenetic levels
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  • the mortality rate of EOC has not been significantly changed for several decades
  • Sequencing revealed that almost all tumors (96%) had mutations in TP53, which serves as a major driver of this cancer
  • Low-prevalence but statistically significant mutations in nine other genes including NF1, BRCA1, BRCA2, RB1, and CDK12 were also identified, but the majority of genes were mutated at low frequency, making it difficult to distinguish between driver and passenger mutations
  • KPNB1 inhibition via any of three KPNB1 siRNAs or importazole treatment induced apoptosis in human EOC cell lines (Fig. 3 A–F and Fig. S4), and was accompanied by an increase in the expression levels of the proapoptotic proteins BAX and cleaved caspase-3
  • Stable overexpression of KPNB1 in SKOV3 and OVCAR3 (Fig. S6) significantly accelerated cell proliferation/survival (Fig. 5 A–C), confirming that KPNB1 functions as an oncogene in EOC
  • KPNB1 overexpression significantly decreased caspase-3/7 activity (Fig. 5D), in addition to the expression levels of cleaved caspase-3 and BAX proteins (Fig. 5E). KPNB1 overexpression also decreased p21 and p27 protein levels (Fig. 5E), as opposed to their increase by KPNB1 inhibition
  • KPNB1 functions as an antiapoptotic and proproliferative oncogene in EOC.
  • Patients with higher expression levels of KPNB1 showed earlier recurrence and worse prognosis than those with lower expression levels of KPNB1
  • KPNB1 acts as an oncogene in human EOC and represents a promising therapeutic target.
  • ivermectin treatment suppressed cell proliferation/viability in a dose-dependent manner (Fig. 7A), indicating that it exerts an antitumor effect on EOC
  • ivermectin also induced apoptosis
  • ivermectin increased the expression levels of BAX, and cleaved PARP, as well as p21 and p27
  • KPNB1 inhibition is responsible for the antitumor effect of ivermectin
  • we found that ivermectin synergistically reduced cell proliferation/viability in combination with paclitaxel in human EOC cells
  • Single treatment of ivermectin or paclitaxel reduced tumor growth in nude mice, but, notably, combination treatment of ivermectin and paclitaxel almost completely suppressed tumor growth
  • ERBB2, is amplified and overexpressed in many cancers, including breast (31), ovary (31), colon (32), bladder (33), non-small-cell lung (34), and gastric cancer (35), and is a poor prognostic factor in certain cancer types
  • KPNB1 was the second-highest-ranked gene identified in our screen
  • Increased KPNB1 protein levels have been reported in several cancers, including cervical cancer (42), hepatocellular carcinoma (43), and glioma (44), suggesting KPNB1’s oncogenic potential in these tumor types
  • our findings suggest that KPNB1 might serve as a master regulator of cell cycle by regulating several cell cycle-related proteins, including p21, p27, and APC/C family members
  • higher and/or more-frequent doses of ivermectin than currently approved for humans are well tolerated in humans
  • none of the mice in this study treated with the effective dosage of ivermectin for in vivo anticancer therapy showed severe adverse event
  • we found that the combination of ivermectin and paclitaxel produces a stronger antitumor effect on EOC cell lines than either drug alone
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    Ivermectin found to be pro-apoptotic for the epithelial ovarian cancer oncogene, KPNB1 in in Vivo study.  This effective anti-parasitic drug inhibits the KPNB1 oncogene.
Nathan Goodyear

Renin-angiotensin system and cancer: A review - 0 views

  • crucial role of the RAS in the development and maintenance of cancer
  • kidneys, which produce renin in response to decreased arterial pressure, reduced sodium in the distal tubule, or sympathetic nervous system activity via the β-adrenergic receptors
  • Renin is secreted from the juxtaglomerular cells into the bloodstream where it encounters angiotensinogen (AGN), normally produced by the liver
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  • Renin catalyses the conversion of AGN to angiotensin I (ATI), which is quickly cleaved by angiotensin converting enzyme (ACE) to form angiotensin II (ATII)
  • ATII triggers the release of aldosterone from the adrenal glands, which stimulates reabsorption of sodium and water and thereby increases blood volume and blood pressure
  • ATII also acts on smooth muscle to cause vasoconstriction of the arterioles
  • ATII promotes the release of antidiuretic hormone from the posterior pituitary gland, which results in water retention and triggers the thirst reflex
  • ability of non-CSCs to ‘de-differentiate’ into CSCs due to epigenetic or environmental factors, which further increases the complexity of tumour biology and treatment
  • efficacy of RAS modulators on cancer in both cancer models and cancer patients
  • A localised (‘paracrine’) RAS mechanism has been identified in many types of cancers, and interruption of the control of the RAS is thought to be the basis for its role in cancer
  • Components of the RAS are expressed by these CSCs, supporting the hypothesis of the presence of a ‘paracrine RAS’ in regulating these CSCs
  • Renin is an enzyme normally released by the kidneys in response to falling arterial pressure
  • a study of GBM demonstrating overexpression of PRR coupled with the observation that inhibition of renin reduces cellular proliferation and promotes apoptosis
  • PRR has been found to be vital for normal Wnt signalling
  • A major focus of PRR research is its relationship with Wnt signalling
  • suggest a crucial role for PRR activation on the proliferation of CSCs, possibly via Wnt/β-catenin signalling, leading to carcinogenesis.
  • Angiotensin converting enzyme (ACE), also known as CD143, is the endothelial-bound peptidase which physiologically converts ATI to ATII
  • ACE is crucial in the regulation of blood pressure, angiogenesis and inflammation
  • results suggest that an overactive ACE promotes cancer growth and progression, and an inhibited or low-activity ACE may have cancer-protective effects
  • When bound to ATII or ATIII it causes vasoconstriction by stimulating the release of vasopressin, reabsorption of water and sodium by promoting secretion of aldosterone and insulin, fibrosis, cellular growth and migration, pro-inflammation, glucose release from the liver, increased plasma triglyceride concentration, and reduced gluconeogenesis
  • ATIIR1 is a G-protein-coupled receptor, with downstream signalling involved in vasodilation, hypertrophy and NF-κB activation leading to TNF-α and PAI-1 expression
  • ATIIR1 has well-documented links with cancer, with one study demonstrating its overexpression in ~20% of breast cancer patients
  • the effect of RAS dysregulation has been associated with increased VEGF expression and angiogenesis in cancers
  • In ovarian and cervical cancer, ATIIR1 overexpression has been shown to be an indicator of tumour invasiveness
  • administration of ATIIR1 blockers (ARBs) have been associated with reduced tumour size, reduction in tumour vascularisation, lower occurrence of metastases, and lower VEGF levels
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    Great review on RAS in cancer.
Nathan Goodyear

Curcumin induces chemo/radio-sensitization in ovarian cancer cells and curcumin nanopar... - 0 views

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    Curcumin increases chemosensitization of ovarian cancer.
Nathan Goodyear

Oncotarget | Vitamin C and Doxycycline: A synthetic lethal combination therapy targetin... - 0 views

  • These eight distinct cancer types included: DCIS, breast (ER(+) and ER(-)), ovarian, prostate, lung, and pancreatic carcinomas, as well as melanoma and glioblastoma. Doxycycline was also effective in halting the propagation of primary cultures of CSCs from breast cancer patients, with advanced metastatic disease (isolated from ascites fluid and/or pleural effusions)
  • Doxycycline behaves as a strong radio-sensitizer, successfully overcoming radio-resistance in breast CSCs
  • cancer cells can indeed escape the effects of Doxycycline, by reverting to a purely glycolytic phenotype. Fortunately, the metabolic inflexibility conferred by this escape mechanism allows Doxycycline-resistant (DoxyR) CSCs to be more effectively targeted with many other metabolic inhibitors, including Vitamin C, which functionally blocks aerobic glycolysis
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  • Vitamin C inhibits GAPDH (a glycolytic enzyme) and depletes the cellular pool of glutathione, resulting in high ROS production and oxidative stress
  • DoxyR CSCs are between 4- to 10-fold more susceptible to the effects of Vitamin C
  • Doxycycline and Vitamin C may represent a new synthetic lethal drug combination for eradicating CSCs, by ultimately targeting both mitochondrial and glycolytic metabolism
  • inhibiting their propagation in the range of 100 to 250 µM
  • metabolic flexibility in cancer cells allows them to escape therapeutic eradication, leading to chemo- and radio-resistance
  • used doxycycline to pharmacologically induce metabolic inflexibility in CSCs, by chronically inhibiting mitochondrial biogenesis
  • This treatment resulted in a purely glycolytic population of surviving cancer cells
  • DoxyR cells are mainly glycolytic
  • MCF7 cells survive and develop Doxycycline-resistance, by adopting a purely glycolytic phenotype
  • Cancer stem cells (CSCs) are thought to be the “root cause” of tumor recurrence, distant metastasis and therapy-resistance
  • the conserved evolutionary similarities between aerobic bacteria and mitochondria, certain classes of antibiotics inhibit mitochondrial protein translation, as an off-target side-effect
  • Vitamin C was more potent than 2-DG; it inhibited DoxyR CSC propagation by > 90% at 250 µM and 100% at 500 µM
  • IC-50
  • DoxyR CSCs are between 4- to 10-fold more sensitive to Vitamin C than control MCF7 CSCs
  • Berberine, which is a naturally occurring antibiotic that also behaves as an OXPHOS inhibitor
  • treatment with Berberine effectively inhibited the propagation of the DoxyR CSCs by > 50% at 1 µM and > 80% at 10 µM.
  • Doxycycline, a clinically approved antibiotic, induces metabolic stress in cancer cells. This allows the remaining cancer cells to be synchronized towards a purely glycolytic phenotype, driving a form of metabolic inflexibility
  • Doxycycline-driven aerobic glycolysis
  • new synthetic lethal strategy for eradicating CSCs, by employing i) Doxycycline (to target mitochondria) and ii) Vitamin C (to target glycolysis)
  • Doxycycline inhibits mitochondrial biogenesis and OXPHOS,
  • hibits glycolytic metabolism by targeting and inhibiting the enzyme GAPDH
  • CSCs act as the main promoter of tumor recurrence and patient relapse
  • a metabolic shift from oxidative to glycolytic metabolism represents an escape mechanism for breast cancer cells chronically-treated with a mitochondrial stressor like Doxycycline, as mitochondrial dys-function leads to a stronger dependence on glucose
  • Vitamin C has been demonstrated to selectively kill cancer cells in vitro and to inhibit tumor growth in experimental mouse models
  • many of these actions have been attributed to the ability of Vitamin C to act as a glycolysis inhibitor, by targeting GAPDH and depleting the NAD pool
  • here we show that DoxyR CSCs are more vulnerable to the inhibitory effects of Vitamin C, at 4- to 10-fold lower concentrations, between 100 to 250 μM
  • concurrent use of Vitamin C, with standard chemotherapy, reduces tumor recurrence and patient mortality
  • after oral administration, Vitamin C plasma levels reach concentrations of ~70-220 μM
  • intravenous administration results in 30- to 70- fold higher plasma concentrations of Vitamin C
  • pro-oxidant activity results from Vitamin C’s action on metal ions, which generates free radicals and hydrogen peroxide, and is associated with cell toxicity
  • it has been shown that high-dose Vitamin C is more cytotoxic to cancer cells than to normal cells
  • This selectivity appears to be due to the higher catalase content observed in normal cells (~10-100 fold greater), as compared to tumor cells. Hence, Vitamin C may be regarded as a safe agent that selectively targets cancer cells
  • the concurrent use of Doxycycline and Vitamin C, in the context of this infectious disease, appeared to be highly synergistic in patients
  • Goc et al., 2016, showed that Doxycycline is synergistic in vitro with certain phytochemicals and micronutrients, including Vitamin C, in the in vitro killing of the vegetative spirochete form of Borrelia spp., the causative agent underlying Lyme disease
  • Doxycycline, an FDA-approved antibiotic, behaves as an inhibitor of mitochondrial protein translation
  • CSCs successfully escape from the anti-mitochondrial effects of Doxycycline, by assuming a purely glycolytic phenotype. Therefore, DoxyR CSCs are then more susceptible to other metabolic perturbations, because of their metabolic inflexibility
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    Not especially new, but IV vitamin C + daily doxycycline found to kill cancer stem cells.
Nathan Goodyear

Meta-Analysis of BRCA1 and BRCA2 Penetrance - 0 views

  • The resulting cumulative risks by age 70 years are as follows: breast cancer risk of 55% (95% CI, 50% to 59%) for BRCA1 and 47% (95% CI, 42% to 51%) for BRCA2 mutation carriers;and ovarian cancer risk of 39% (95% CI,34% to 45%) for BRCA1 and 17% (95% CI,13% to 21%) for BRCA2 mutation carriers
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    good meta-analysis and discussion of the heterogenous penetrance of BRCA1 and BRCA2.  This study found lower penetrance compared to previous studies i.e. 55% breast cancer risk and 39% ovarian cancer risk in BRCA1
Nathan Goodyear

Human cytomegalovirus in high grade serous ovarian cancer possible implications for pat... - 0 views

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    CMV plays role in ovarian cancer. EBV, HPV have shown to play role in other cancers. The likely mechanism is via genetic incorporation of viral genome into the cancer genome.
Nathan Goodyear

Metformin intake is associated with better survival in ovarian cancer - Kumar - 2012 - ... - 0 views

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    metformin improves survival rate in ovarian cancer
Nathan Goodyear

http://jeffreydachmd.com/wp-content/uploads/2016/02/Ivermectin-inactivates-blocks-kinas... - 0 views

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    Ivermectin found to block PAK-1 in ovarian cancer cell lines.
Nathan Goodyear

Anti-Cancer Tumor Cell Necrosis of Epithelial Ovarian Cancer Cell Lines Depends on High... - 0 views

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    PNC-27 binds to HDM-2 which is highly expressed on ovarian cancer cancer cell lines. The result is transmembrane pore formation and apoptosis independent cell necrosis.
Nathan Goodyear

From the Cover: Pharmacologic doses of ascorbate act as a prooxidant and decrease growt... - 0 views

  • An extensive panel of 43 tumor and 5 normal cell lines were exposed to ascorbate in vitro for ≤2 h to mimic clinical pharmacokinetics
  • effective concentration that decreased survival 50% (EC50) was determined. EC50 was <10 mM for 75% of tumor cells tested, whereas cytotoxicity was not evident in normal cells with >20 mM ascorbate
  • The addition of catalase to the medium ameliorated death of ovarian carcinoma (Ovcar5), pancreatic carcinoma (Pan02), and glioblastoma (9L) cells exposed to 10 mM ascorbate (1 h), indicating cytotoxicity was mediated by H2O2
  • ...8 more annotations...
  • A treatment dose of 4 g ascorbate/kg body weight either once or twice daily did not produce any discernible adverse effects
  • Xenograft experiments showed that parenteral ascorbate as the only treatment significantly decreased both tumor growth and weight by 41–53%
  • Peak plasma concentrations of ascorbate approached 30 mM
  • Pharmacologic concentrations of ascorbate decreased tumor volumes 41–53% in diverse cancer types known for both their aggressive growth and limited treatment options.
  • Our findings showed that pharmacologic ascorbic acid concentrations were cytotoxic to many types of cancer cells in vitro (Fig. 1A) and significantly impeded tumor progression in vivo without toxicity to normal tissues
  • The amelioration of ascorbate cytotoxicity in vitro by the addition of catalase was consistent among sensitive cancer cells (Fig. 1B) and points unambiguously to H2O2 generation in the extracellular medium
  • the current in vivo data support that pharmacologic ascorbate concentrations, which can readily be achieved in humans (Fig. 3E), diminished growth of several aggressive cancer types in mice (Fig. 2) without causing apparent adverse effects.
  • These intratumoral H2O2 concentrations of >125 μM persisted for >3 h after ascorbate administration
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    Tumor xenograft model in mice finds reduction in growth rates of ovarian cancer, pancreatic cancer, and glioblastoma with daily IV vitamin C.
Nathan Goodyear

Potentiation of Melphalan Cytotoxicity in Human Ovarian Cancer Cell Lines by Glutathion... - 0 views

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    glutathione levels inversely associated with drug resistance in the treatment of ovarian cancer.
Nathan Goodyear

Effect of Screening on Ovarian Cancer Mortality, June 8, 2011, Buys et al. 305 (22): 22... - 0 views

  • Among women in the general US population, simultaneous screening with CA-125 and transvaginal ultrasound compared with usual care did not reduce ovarian cancer mortality
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    Ovarian Cancer screening provides no benefit
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