Use of in vitro human keratinocyte models to study the effect of cooling on chemotherapy drug-induced cytotoxicity

Abstract

A highly distressing side-effect of cancer chemotherapy is chemotherapy-induced alopecia (CIA). Scalp cooling remains the only treatment for CIA, yet there is no experimental evidence to support the cytoprotective capacity of cooling. We have established a series of in vitro models for the culture of human keratinocytes under conditions where they adopt a basal, highly-proliferative phenotype thus resembling the rapidly-dividing sub-population of native hair-matrix keratinocytes. Using a panel of chemotherapy drugs routinely used clinically (docetaxel, doxorubicin and the active metabolite of cyclophosphamide 4-OH-CP), we demonstrate that although these drugs are highlycytotoxic, cooling can markedly reduce or completely inhibit drug cytotoxicity, in agreement with clinical observations. By contrast, we show that cytotoxicity caused by specific combinatorial drug treatments cannot be adequately attenuated by cooling, supporting data showing that such treatments do not always respond well to cooling clinically. Importantly, we provide evidence that the choice of temperature may be critical in determining the efficacy of cooling in rescuing cells from drug-mediated toxicity. Therefore, despite their reductive nature, these in vitro models have provided experimental evidence for the clinically-reported cytoprotective role of cooling and represent useful tools for future studies on the molecular mechanisms of cooling-mediated cytoprotection. Chemotherapy-induced alopecia (CIA) is the most common and distressing side effect of anticancer chemotherapy (Wang et al., 2006) and the anxiety caused by the prospect of CIA can cause patients to even refuse treatment in certain cases (Munstedt et al., 1997). Thus development of an effective CIA preventative regime represents an important challenge in oncology (Paus et al., 2013). CIA occurs due to damage to the hair follicles, which comprise various cell types including hair matrix keratinocytes, which represent the most rapidly dividing cell subset and contribute to follicular structure and function (Roh et al., 2005). As chemotherapeutic drugs such as taxanes (e.g. docetaxel), alkylating agents (e.g. cyclophosphamide) and anthracyclines/DNA intercalating agents (e.g. doxorubicin) target cancer cells due to their rapid division rate, these drugs also target the matrix keratinocytes which results in hair loss (Paus et al., 2013). AbbreviationsCurrently the only available preventative treatment for CIA is head (scalp) cooling. Scalp cooling or hypothermia during the administration of chemotherapy drugs can substantially reduce hair loss (Protiere et al., 2002) and has been used since the 1970s (Dean et al., 1979). Clinically it has been shown that scalp cooling can substantially reduce the incidence of hair loss in response to individual drugs, including cyclophosphamide, doxorubicin and cisplatin (Breed et al., 2011;van den Hurk et al., 2012). However, for combined treatment regimens, such as sequential treatment with docetaxel (taxotere), doxorubicin (adriamycin) an...

The Cytotoxicity Effects of Outer Membrane Vesicles Isolated From Hospital and Laboratory Strains of Pseudomonas Aeruginosa on Human Keratinocyte Cell Line

“…Data showed that at low concentration of OMVs, the cells continued to grow rapidly leading to the increase of overall biomass compared with the control, and this was evident with the first concentration for the laboratory strain. These findings are consistent with that of (Al-Tameemi et al, 2014) who reported that stimulation of cells with low concentration of doxorubicin and 4-OH-CP led to an overall increase in HaCaT cells biomass. The results of the current study show that the most affected cells were the one exposed to the second concentration of hospital strain and the less affected cells were the first concentration of OMVs for laboratory strain.…”

Cooling-mediated protection from chemotherapy drug-induced cytotoxicity in human keratinocytes by inhibition of cellular drug uptake

“…We employed these models to study the effects of cooling on chemotherapy drug-mediated cytotoxicity. Using a panel of drugs (including both taxanes and anthracyclines) routinely used in the clinic for treatment of cancers such as breast cancer, we demonstrated for the first time that although the drugs were highly cytotoxic, cooling during drug treatment markedly reduced or even completely prevented drug cytotoxicity, in agreement with observations of the ability of scalp cooling to prevent HF toxicity in the clinic [13]. Equally importantly, we provided evidence that the precise cooling conditions (temperature) was a critical factor in determining the overall ability of cooling in rescuing cells from drugmediated toxicity.…”

A Clinical and Biological Guide for Understanding Chemotherapy-Induced Alopecia and Its Prevention

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