Low doses of cisplatin or gemcitabine plus Photofrin/photodynamic therapy: Disjointed cell cycle phase-related activity accounts for synergistic outcome in metastatic non-small cell lung cancer cells (H1299).

We compared the effects of monotherapy (photodynamic therapy or chemotherapy) versus combination therapy (photodynamic therapy plus a specific drug) on the non-small cell lung cancer cell line H1299. Our aim was to evaluate whether the additive/synergistic effects of combination treatment were such that the cytostatic dose could be reduced without affecting treatment efficacy. Photodynamic therapy was done by irradiating Photofrin-preloaded H1299 p53/p16-null cells with a halogen lamp equipped with a bandpass filter. The cytotoxic drugs used were cis-diammine-dichloroplatinum [II] (CDDP or cisplatin) and 2',2'-difluoro-2'-deoxycytidine (gemcitabine). Various treatment combinations yielded therapeutic effects (trypan blue dye exclusion test) ranging from additive to clearly synergistic, the most effective being a combination of photodynamic therapy and CDDP. To gain insight into the cellular response mechanisms underlying favorable outcomes, we analyzed the H1299 cell cycle profiles and the expression patterns of several key proteins after monotherapy. In our conditions, we found that photodynamic therapy with Photofrin targeted G0-G1 cells, thereby causing cells to accumulate in S phase. In contrast, low-dose CDDP killed cells in S phase, thereby causing an accumulation of G0-G1 cells (and increased p21 expression). Like photodynamic therapy, low-dose gemcitabine targeted G0-G1 cells, which caused a massive accumulation of cells in S phase (and increased cyclin A expression). Although we observed therapeutic reinforcement with both drugs and photodynamic therapy, reinforcement was more pronounced when the drug (CDDP) and photodynamic therapy exert disjointed phase-related cytotoxic activity. Thus, if photodynamic therapy is appropriately tuned, the dose of the cytostatic drug can be reduced without compromising the therapeutic response

Consensus statement on abusive head trauma in infants and young children

Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 years. A multidisciplinary team bases this diagnosis on history, physical examination, imaging and laboratory findings. Because the etiology of the injury is multifactorial (shaking, shaking and impact, impact, etc.) the current best and inclusive term is AHT. There is no controversy concerning the medical validity of the existence of AHT, with multiple components including subdural hematoma, intracranial and spinal changes, complex retinal hemorrhages, and rib and other fractures that are inconsistent with the provided mechanism of trauma. The workup must exclude medical diseases that can mimic AHT. However, the courtroom has become a forum for speculative theories that cannot be reconciled with generally accepted medical literature. There is no reliable medical evidence that the following processes are causative in the constellation of injuries of AHT: cerebral sinovenous thrombosis, hypoxic-ischemic injury, lumbar puncture or dysphagic choking/vomiting. There is no substantiation, at a time remote from birth, that an asymptomatic birth-related subdural hemorrhage can result in rebleeding and sudden collapse. Further, a diagnosis of AHT is a medical conclusion, not a legal determination of the intent of the perpetrator or a diagnosis of murder. We hope that this consensus document reduces confusion by recommending to judges and jurors the tools necessary to distinguish genuine evidence-based opinions of the relevant medical community from legal arguments or etiological speculations that are unwarranted by the clinical findings, medical evidence and evidence-based literature

Twilight effects of low doses of ionizing radiation on cellular systems: a bird's eye view on current concepts and research.

The debate about the health risks from low doses of radiation is vigorous and often acrimonious since many years and does not appear to weaken. Being far from completeness, this review presents only a bird's eye view on current concepts and research in the field. It is organized and divided in two parts. The first is dedicated to molecular responses determined by radiation-induced DNA ruptures. It focuses its attention on molecular pathways that are activated by ATM and tries to describe the variegated functions and specific roles of Chk2 and p53 and other proteins in sensing, promoting and executing DNA repair. The second part is more concerned with the risk associated with exposure to low dose radiation and possible effects that the radiation-affected cell may undergo. These effects include induction of apoptosis and mitotic catastrophe, bystander effect and genomic instability, senescence and hormetic response. Current hypotheses and research on these issues are briefly discussed

Cells derived from normal or cancer breast tissue exhibit different growth properties when deprived of arginine.

Arginine deprivation impairs cell proliferation more strong in cancer than in normal cells; thus, it has been proposed that such an effect could be exploited for cancer therapy. We have compared the effect of arginine deprivation on normal and cancer cells, studying growth rate, morphology, and protein expression patterns in immortalized human MCF10a cells and in MCF7 cells. Arginine deprivation forces MCF10a cells into irreversible senescence while the vast majority of MCF7 cells become quiescent and resume normal growth following arginine re-addition. Arginine deprivation induced a significant burst of p21cip1 in both cell lines that were reversible in MCF7 and irreversible in MCF10 cells. In the latter cells, p21cip1 increase was accompanied by a time-dependent increase of p16INK4A. Similar effects could be obtained by treating both cell types with α-difluoro-methyl-ornithine, but not with Nω-hydroxy-L-arginine, drugs that interfere specifically but differently with the major pathways of arginine metabolism. Our data suggest that derangement in polyamine synthesis is the main consequence of arginine starvation

Cells derived from normal or cancer breast tissue exhibit different growth properties when deprived of arginine.

Arginine deprivation impairs cell proliferation more strong in cancer than in normal cells; thus, it has been proposed that such an effect could be exploited for cancer therapy. We have compared the effect of arginine deprivation on normal and cancer cells, studying growth rate, morphology, and protein expression patterns in immortalized human MCF10a cells and in MCF7 cells. Arginine deprivation forces MCF10a cells into irreversible senescence while the vast majority of MCF7 cells become quiescent and resume normal growth following arginine re-addition. Arginine deprivation induced a significant burst of p21cip1 in both cell lines that were reversible in MCF7 and irreversible in MCF10 cells. In the latter cells, p21cip1 increase was accompanied by a time-dependent increase of p16INK4A. Similar effects could be obtained by treating both cell types with a-difluoro-methyl-ornithine, but not with Nx-hydroxy-L-arginine, drugs that interfere specifically but differently with the major pathways of arginine metabolism. Our data suggest that derangement in polyamine synthesis is the main consequence of arginine starvation

Low doses of cisplatin or gemcitabine plus Photofrin-photodynamic therapy: disjointed cell cycle phase-related activity accounts for synergistic outcome in metastatic non-small cell lung cancer cells (H1299).

We compared the effects of monotherapy (photodynamic therapy or chemotherapy) versus combination therapy (photodynamic therapy plus a specific drug) on the non-small cell lung cancer cell line H1299. Our aim was to evaluate whether the additive/synergistic effects of combination treatment were such that the cytostatic dose could be reduced without affecting treatment efficacy. Photodynamic therapy was done by irradiating Photofrin-preloaded H1299 p53/p16-null cells with a halogen lamp equipped with a bandpass filter. The cytotoxic drugs used were cis-diammine-dichloroplatinum [II] (CDDP or cisplatin) and 2',2'-difluoro-2'-deoxycytidine (gemcitabine). Various treatment combinations yielded therapeutic effects (trypan blue dye exclusion test) ranging from additive to clearly synergistic, the most effective being a combination of photodynamic therapy and CDDP. To gain insight into the cellular response mechanisms underlying favorable outcomes, we analyzed the H1299 cell cycle profiles and the expression patterns of several key proteins after monotherapy. In our conditions, we found that photodynamic therapy with Photofrin targeted G0-G1 cells, thereby causing cells to accumulate in S phase. In contrast, low-dose CDDP killed cells in S phase, thereby causing an accumulation of G0-G1 cells (and increased p21 expression). Like photodynamic therapy, low-dose gemcitabine targeted G0-G1 cells, which caused a massive accumulation of cells in S phase (and increased cyclin A expression). Although we observed therapeutic reinforcement with both drugs and photodynamic therapy, reinforcement was more pronounced when the drug (CDDP) and photodynamic therapy exert disjointed phase-related cytotoxic activity. Thus, if photodynamic therapy is appropriately tuned, the dose of the cytostatic drug can be reduced without compromising the therapeutic response

Low doses of cisplatin or gemcitabine plus photofrin/photodynamic therapy : disjointed cell cycle phase-related activity accounts for synergistic outcome in metastatic non-small cell lung cancer cells (H1299)

We compared the effects of monotherapy (photodynamic therapy or chemotherapy) versus combination therapy (photodynamic therapy plus a specific drug) on the non-small cell lung cancer cell line H1299. Our aim was to evaluate whether the additive/synergistic effects of combination treatment were such that the cytostatic dose could be reduced without affecting treatment efficacy. Photodynamic therapy was done by irradiating Photofrin-preloaded H1299 p53/p16-null cells with a halogen lamp equipped with a bandpass filter. The cytotoxic drugs used were cis-diammine-dichloroplatinum [II] (CDDP or cisplatin) and 2',2'-difluoro-2'-deoxycytidine (gemcitabine). Various treatment combinations yielded therapeutic effects (trypan blue dye exclusion test) ranging from additive to clearly synergistic, the most effective being a combination of photodynamic therapy and CDDP. To gain insight into the cellular response mechanisms underlying favorable outcomes, we analyzed the H 1299 cell cycle profiles and the expression patterns of several key proteins after monotherapy. In our conditions, we found that photodynamic therapy with Photofrin targeted G(0)-G(1) cells, thereby causing cells to accumulate in S phase. In contrast, low-dose CDDP killed cells in S phase, thereby causing an accumulation of GO-G, cells (and increased p21 expression). Like photodynamic therapy, low-dose gemcitabine targeted GO-G, cells, which caused a massive accumulation of cells in S phase (and increased cyclin A expression). Although we observed therapeutic reinforcement with both drugs and photodynamic therapy, reinforcement was more pronounced when the drug (CDDP) and photodynamic therapy exert disjointed phase-related cytotoxic activity. Thus, if photodynamic therapy is appropriately tuned, the dose of the cytostatic drug can be reduced without compromising the therapeutic response

Photodynamic therapy with indocyanine green complements and enhances low-dose cisplatin cytotoxicity in MCF-7 breast cancer cells.

OBJECTIVE: We investigated the effects of photodynamic therapy (PDT) combined with low-dose chemotherapy on breast cancer cells. Photodynamic treatment was administered by irradiating indocyanine green-preloaded MCF-7 cells with an IR diode laser source at 805 nm; cisplatin was used for chemotherapy. METHODS: The dose-response phenomena associated with the two treatments administered individually and together were evaluated with the following tests: trypan blue dye exclusion, 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay, clonogenic survival, thymidine and methionine incorporation, and insulin-dependent and insulin-independent glucose transport. RESULTS: Viability and metabolic data demonstrated mutual reinforcement of therapeutic efficacy. However, isobolographic analysis of quantal and variable data indicated that reinforcement was additive according to trypan blue data and synergistic according to MTT data. To investigate the molecular mechanisms underlying alterations in cell proliferation and apoptosis, we evaluated (by Western blotting) the expression of proteins Bcl-2, Bax, Bcl-X(L), p21, p53, and poly(ADP-ribose) polymerase. Photodynamic treatment caused transient selective destruction of Bcl-2 and up-regulation of Bax. It also induced apoptosis in a limited fraction of cells (10-12%). Flow cytometry data showed that PDT killed mostly G(1)-phase cells, whereas cisplatin killed mostly S-phase cells. This disjointed phase-related effect may account for the favorable effects exerted by combined treatment. CONCLUSIONS: Our findings imply that low doses of cytostatic drugs may be as effective or even more effective than currently used doses if appropriately combined with PDT

MICROGRAVITY ALTERS BASAL AND INSULIN-MEDIATED METABOLIC ACTIVITY OF NORMAL AND NEOPLASTIC CELLS.

In this paper we report the behaviour of normal vascular smooth muscle cells and transformed breast cancer cells under normal versus simulated microgravity conditions by comparing cell proliferation, Glucose transport, Methionine uptake and protein synthesis. Modeled microgravity profoundly affects cell growth (especially in normal cells) and Glucose or Methionine metabolism (although to different extent in the two cell lines). Since both cells own responsive insulin receptors, the comparison was extended to insulin-stimulated versus unstimulated conditions. We report that the detected metabolic changes were strongly enhanced when the cells were simultaneously stimulated with insulin and subjected to modeled microgravity stress. Such observations may have important returns for human health in space; they deserve further attention