In vitro competition between two transmissible cancers, and potential implications for their host, the Tasmanian devil

Since the emergence of a transmissible cancer, devil facial tumour disease (DFT1), in the 1980s, wild Tasmanian devil populations have been in decline. In 2016, a second, independently evolved transmissible cancer (DFT2) was discovered raising concerns for survival of the host species. Here, we applied experimental and modelling frameworks to examine competition dynamics between the two transmissible cancers in vitro. Using representative cell lines for DFT1 and DFT2, we have found that in monoculture, DFT2 grows twice as fast as DFT1 but reaches lower maximum cell densities. Using co-cultures, we demonstrate that DFT2 outcompetes DFT1: the number of DFT1 cells decreasing over time, never reaching exponential growth. This phenomenon could not be replicated when cells were grown separated by a semi-permeable membrane, consistent with exertion of mechanical stress on DFT1 cells by DFT2. A logistic model and a Lotka-Volterra competition model were used to interrogate monoculture and co-cul..., Cell cultures 
Representative cell lines for DFT1 (4906, also known as 88 [41]) and DFT2 (RV also known as TD467 or 202T1 [42]) were cultured as previously described [41], [42]. DFT1 and DFT2 cell lines have been shown to share many characteristics of in vivo tumours [43], [44], [45], making these cell lines a useful in vitro study system. Cells were maintained in RPMI-1640 media with GlutaMAX (Gibco, 61870036) supplemented with 10% heat-inactivated FBS (Gibco, 10500-064) and 50 ug/mL penicillin/streptomycin (Gibco, 15070063) or 50 ug/mL of gentamicin (Sigma, G1397) at 35°C and 5% CO2. Upon reaching 80-90% confluency, cells were detached using TrypLE Express (Gibco, 12605010) and passaged 1:3. Cells were maintained below Passage 30. DFT1 cell lines were tested for mycoplasma in [46]. All DFT2 cells were tested for mycoplasma [insert details such as kit name] when they entered the lab. They have been passaged successfully in a mycoplasma free tissue culture facility since then.
Transduct..., , # In vitro competition between two transmissible cancers, and potential implications for their host, the Tasmanian devil

[https://doi.org/10.5061/dryad.3j9kd51s6](https://doi.org/10.5061/dryad.3j9kd51s6)

This dataset contains the results of two experiments: (1) direct DFT1 & DFT2 co-cultures and (2) transwell DFT1 & DFT2 co-cultures.

## Description of the data and file structure

Flow cytometry dataset consists of **.fcs** files with associated **settings.csv** files. Gating events in these allowed to calculate the number of cells for the two experiments, which can be found in the files described below. Coordinates for each gate can be found in the **gating.csv** files.

**(1) Direct co-culture**

File name: **DFT1&DFT2_cocultures.xlsx**

File structure: long format Exel table with the following columns:

* Experiment: experiment ID - categorical variable
* Replicate: replicate number, experiments were performed in triplicates - categorical variable
* Culture: rati...

# 两种可传播癌症的体外竞争及其对宿主塔斯马尼亚恶魔（Tasmanian devil）的潜在影响
[https://doi.org/10.5061/dryad.3j9kd51s6](https://doi.org/10.5061/dryad.3j9kd51s6)

自20世纪80年代第一种可传播癌症——袋獾面部肿瘤病（devil facial tumour disease, DFT1）出现以来，野生袋獾种群数量持续下降。2016年，研究人员发现了第二种独立演化产生的可传播癌症（DFT2），这一发现引发了人们对该宿主物种生存的担忧。本研究通过实验与建模框架，探究了两种可传播癌症的体外竞争动态。我们利用DFT1与DFT2的代表性细胞系开展实验，结果发现：在单培养（monoculture）条件下，DFT2的增殖速率是DFT1的两倍，但最终达到的最大细胞密度更低。通过共培养（co-culture）实验，我们证实DFT2可竞争性排斥DFT1：DFT1的细胞数量随时间推移持续减少，始终无法进入指数增殖阶段。当细胞被半透膜（semi-permeable membrane）分隔培养时，这一现象并未出现，这与DFT2对DFT1细胞施加机械应激的结论相符。本研究采用逻辑斯蒂模型（logistic model）与洛特卡-沃尔泰拉竞争模型（Lotka-Volterra competition model），对单培养及共培养……[原文截断]
细胞培养
DFT1的代表性细胞系（4906，又名88[41]）与DFT2的代表性细胞系（RV，又名TD467或202T1[42]）的培养方法参照既往研究[41,42]。已有研究证实，DFT1与DFT2细胞系具备体内肿瘤的诸多特征[43-45]，因此可作为优质的体外研究模型。细胞培养条件为：使用添加了GlutaMAX的RPMI-1640培养基（Gibco，货号61870036），补充10%热灭活胎牛血清（FBS，Gibco，货号10500-064）、50 μg/mL青霉素-链霉素（penicillin/streptomycin，Gibco，货号15070063）或50 μg/mL庆大霉素（gentamicin，Sigma，货号G1397），培养温度为35℃，二氧化碳浓度为5%。当细胞汇合度达到80%-90%时，使用TrypLE Express解离液（Gibco，货号12605010）进行细胞解离，并以1:3的比例进行传代。所有细胞的传代代数均控制在30代以内。DFT1细胞系的支原体检测参照文献[46]；DFT2细胞系在引入实验室时均完成了支原体检测[可补充试剂盒名称等细节]，后续均在无支原体的组织培养环境中成功传代。
转导相关实验……[原文截断]，# 两种可传播癌症的体外竞争及其对宿主塔斯马尼亚恶魔的潜在影响

[https://doi.org/10.5061/dryad.3j9kd51s6](https://doi.org/10.5061/dryad.3j9kd51s6)

本数据集包含两项实验的结果：(1) DFT1与DFT2直接共培养实验；(2) Transwell跨室DFT1与DFT2共培养实验。

## 数据与文件结构说明

流式细胞术（Flow cytometry）数据集包含若干**.fcs**格式文件及配套的**settings.csv**文件。通过对这些文件中的门控事件进行分析，可计算得到两项实验的细胞数量，相关结果可参见下述文件。各分选门的坐标信息可在**gating.csv**文件中获取。

**(1) 直接共培养**

文件名：**DFT1&DFT2_cocultures.xlsx**

文件结构：长格式Excel表格，包含以下列：
* Experiment：实验ID，分类变量
* Replicate：重复次数，本实验设置3次生物学重复，分类变量
* Culture：比例……[原文截断]