Review Article

Modelling Cooperative Tumorigenesis in Drosophila

Table 1

Cooperating genes in Drosophila tumorigenesis.

Cell-autonomous cooperative tumorigenesis
1st mutation/mechanism2nd mutation/mechanismPhenotype/references

Cell polarity gene perturbations

Loss of function in apicobasal polarity regulators​ 
Results in cell polarity loss, JNK activation, mild Hippo pathway impairment
Neoplastic overgrowth in whole tissue context and cell polarity loss and apoptosis in clonal context (reviewed in [19])

Scribble (scrib, dlg, lgl) and Par and Crb polarity module gene loss of function​ 
Scribble module loss of function phenotypes dependent on aPKC activation​ 
​ 
RasV12 overexpression​
Dependent on ROS production, TNF (Egr)-JNK signalling, caspase (Dronc) activity​
Dependent on impairment of Hippo signalling​
Dependent on PI3K signalling and glutamate utilization
Invasive neoplastic tumours of the larval eye-antennal epithelium [23, 48, 57, 60, 6568]

scrib loss of function, aPKC-CA overexpression, crb overexpressionInhibition of JNK signallingNeoplastic tumour overgrowth in eye-antennal epithelium [66]

lgl or scrib loss of function​ 
Results in JNK activation
RasV12 overexpression​
Requires Hippo pathway impairment
Neoplastic tumours in the larval wing epithelium [49]

scrib loss of function ​ 
Results in JNK activation
Notchintra (Act) overexpressionInvasive neoplastic tumours in the larval eye-antennal epithelium [23, 66, 69]

scrib loss of function ​ 
Results in JNK activation​ 
​ 
​ 
Abrupt (BTB-POZ Zn finger transcription factor) overexpression​
Results in JNK activation ​
Results in Hippo pathway impairment ​
Results in downregulation of differentiation and Ecdysone response genes
Invasive neoplastic tumours in the eye-antennal and wing epithelial tissues [70]

scrib loss of function​ 
​ 
Taiman (Ecdysone coactivator) ​
Results in reduced differentiation
Invasive neoplastic tumours in the eye-antennal and wing epithelial tissues [70]

scrib loss of function​ 
Results in JNK activation
Slit-Robo2-Ena loss of functionOvergrown tumours in the eye-antennal epithelial tissues [45]

scrib loss of function ​ 
Results in JNK activation​ 
​ 
Slit-Robo overexpression​
Requires Ena​
Results in JNK activation and activation of a positive feedback loop
Excessive extrusion and luminal tumour overgrowth in larval eye-antennal epithelial tissues [45]

lgl loss of function ​ 
Results in Hippo pathway impairment
Inhibition of JNK signallingInvasive neoplastic tumours of the larval/pupal eye neural-epithelium [71]

lgl loss of functionMyc overexpressionInvasive neoplastic tumours of the larval wing epithelium [50]

lgl loss of functionHippo pathway impairmentNeoplastic tumours of the larval wing epithelium [49]

lgl loss of functionNotchintra (Act)  overexpressionNeoplastic tumours of the larval wing epithelium [72]

scrib, dlg or lgl depletion​ 
​ 
cno mutants​
Results in activation of Ras-MAPK signalling
Enhanced neoplastic tumours of the antennal epithelium [73]

Par-1 overexpression​ 
Results in cell polarity loss and Hippo pathway impairment
Eye-antennal and wing tissue overgrowth [74]

Par-1 overexpressionNotchintra (Act)  overexpressionHyperplastic eye-antennal epithelium [75]

Actin cytoskeletal regulators

Activation of Actin cytoskeletal regulators ​ 
Rac1, RhoGEF2, Pbl, RhoV14, Rho1, RokCAT, sqhEE​ 
Results in activation of JNK signalling and cell morphology changes
(Raf gain-of-function) overexpressionInvasive neoplastic tumours of the larval eye-antennal epithelium [76, 77]

RhoGEF2 overexpression​ 
Results in JNK activation and cell morphology changes
Abrupt (BTB-POZ Zn finger transcription factor) overexpression​
Results in reduced expression of differentiation gene, Dac​
Neoplastic tumours of the larval eye-antennal epithelial tissue [78]

Src64B overexpression​ 
Results in JNK activation and cell morphology changes
Blocking JNK ​
Rac1-Dia, Ras-MAPK, Hippo pathway impairment​
Eye-antennal epithelial tissue overgrowth [79]

csk loss of function​ 
(Src activation) ​ 
Depends on Actin cytoskeleton regulators, JNK activation, STAT activation, Hippo pathway impairment, Wingless (Wnt) expression/signalling and insulin-PI3K signalling
overexpression​
Promotes cell proliferation and survival​
Invasive neoplastic tumours of the larval eye-antennal epithelium [8085]

Src42A or Src64B overexpression​ 
Results in Egr independent activation of JNK and Jak-Stat signalling
overexpression​
​ 
​ 
Neoplastic tumours of the larval eye-antennal and wing epithelium [86]

Src64B overexpression​ 
Results in cell morphology changes
Abrupt overexpression​
Reduces expression of differentiation gene and Dac and Dll
Neoplastic tumours of the larval eye-antennal epithelial tissue [78]

Troponin I overexpression​ 
​ 
RasV12 overexpression​
Notchintra (Act) overexpression​
lgl mutant RasV12 overexpression
Tumour overgrowth or neoplastic tumour overgrowth in wing epithelial tissue [87]

Signalling pathway deregulation

RasV12 overexpression
Results in tissue overgrowth, which depends upon EGF-EGFR activation and Arf6 mediated Hedgehog signalling
Eye-antennal and wing epithelial tissue overgrowth [88]

TNF-JNK signallingInvasive neoplastic tumours in the larval eye-antennal epithelium [76, 8991]

Immune signalling and activation of JNKInvasive neoplastic tumours of the adult hindgut epithelium [92]

Ben/dUev1a E2 ubiquitin ligase overexpression ​
Results in JNK activation (via binding Traf2)
Invasive neoplastic tumours in the larval eye-antennal epithelium [9395]

sds22 (PP1) loss of function​
Results in cell morphology/polarity loss ​
Results in Myosin II, JNK activation
Invasive neoplastic tumours of the larval eye-antennal epithelium [96]

PP6 phosphatase (FMT, PpV) knock down​
Results in Tak1-JNK activation
Invasive neoplastic tumours of the eye-antennal epithelium [97]

Infection/inflammation ​
Results in Imd-dTab2-dTak1-JNK signalling and MMP1 expression
Hindgut epithelial tumour invasion [92, 98]

Impaired Hippo pathway signalling​
Results in upregulation of Ras pathway genes, Upd-Jak-Stat signalling
Eye-antennal and wing tissue overgrowth [65, 99]

Lysosomal protein loss of function—deep orange, carnation, vps16AInvasive neoplastic tumours of the larval eye-antennal epithelium [100]

Autophagy loss of function—e.g., Atg8a, Atg7, Atg9, Atg1, Atg13, Syx17
Requires ROS and JNK upregulation
Invasive neoplastic tumours of the larval eye-antennal epithelium [101]

Chromosome remodelling complex mutation polyhomeotic
Depends on ectopic Notch activation
Invasive neoplastic tumours of the larval eye-antennal epithelium [102]

Chinmo (BTB-POZ Zn finger transcription factor) overexpressionOvergrown tumours in the eye-antennal epithelial tissues [69]

Fruitless (BTB-POZ Zn finger transcription factor) overexpressionOvergrown tumours in the eye-antennal epithelial tissues [69]

PTEN knockdown ​
(Elevated PI3K signalling)
Larval-Pupal tracheal epithelial tissue invasive tumours [103]

apc (Wingless/Wnt) signallingAdult midgut epithelial tissue overgrowth [104, 105]

p53, apc, pten knockdown ​
dSmad4, apc, pten knockdown
Adult hindgut epithelial tissue invasive tumours [106]

pico (MRL) overexpression​
chickadee (Profilin) overexpression​
mal (SRF cofactor gene) overexpression​
Requires JNK-MMP1 activity
Glial cell overgrowth and invasion [107]

EGFR activation/overexpression
Depends on Ras and Hh signalling
Eye-antennal and wing epithelial tissue overgrowth [88]

fat loss of function​
(Hippo pathway impairment)
Eye-antennal and wing epithelial tissue overgrowth [108]

bantam micro-RNA expression​
Results in downregulation of Socs36E ​
Leads to increased Jak-Stat signalling
Invasive overgrowth of the larval wing epithelium [109]

miR-10 or miR-375 Micro-RNA expression​
Results in downregulation of Psq transcription factor
Invasive overgrowth of the larval eye-antennal and wing epithelium [52]

miR-8 Micro-RNA expression​
Results in downregulation of Peanut protein expression, cytokinesis blockage, formation of polyploid cells
Invasive overgrowth of the larval wing epithelium [110]

PI3K pathway activation ​
Requires Tor, Sin1, Rictor, Myc, Cyclin D-Cdk4, Rb-E2F and Cdc25 ​
Requires RIOK1, RIOK2
Glia cell invasive brain tumours and eye neural-epithelium tumours [111113]

Notchintra (Act)/Delta overexpression
Results in tissue overgrowth
Eye-antennal and wing tissue overgrowth (reviewed by [114])

overexpressionMef2 overexpressionInvasive neoplastic tumours of the larval eye neural-epithelium [115]

overexpressionChinmo (BTB-POZ Zn finger transcription factor) overexpressionOvergrown tumours in the eye-antennal epithelial tissues [69]

overexpressionFruitless (BTB-POZ Zn finger transcription factor) overexpressionOvergrown tumours in the eye-antennal epithelial tissues [69]

Delta overexpressionOverexpression of transcription factors Psq/Lola (eyeful model)Invasive tumours larval/pupal eye neural-epithelium, which are capable of differentiation to express ELAV [116]

Delta overexpressionOverexpression of Akt or PI3K (Dp110)Invasive tumours larval/pupal eye neural-epithelium, which are capable of differentiation (ELAV expression) [117]

Delta overexpression​
Results in repression of boi gene expression and reduced Hedgehog signalling
Overexpression of mir-7 micro-RNA​
Results in downregulation of ihog translation and reduced Hedgehog signalling
Eye-antennal disc overgrowth and invasive cells cable of differentiation [118]

Delta overexpressionOverexpression of Zfh1 (Zeb1 family transcription factor gene)Invasive tumours larval/pupal eye neural-epithelium, which are capable differentiation to express ELAV [119]

Delta overexpression​
Delta with Pipsqueak/Lola overexpression (eyeful model)
Knockdown of atonal (transcription factor gene) ​
Results in reduced JNK signalling​

Invasive tumours larval/pupal eye neural-epithelium, which are capable differentiation to express ELAV [120]

Delta overexpression​
Delta with Pipsqueak/Lola overexpression (eyeful model)
Knockdown of cut (transcription factor gene) ​
Results in increased reaper  expression and elevated PI3K-Akt signalling​

Invasive tumours in larval/pupal eye-antennal epithelium, which are capable differentiation to express ELAV [121]

Hippo pathway impairment (Yki overexpression)
Results in increased tissue growth through upregulation of cell growth (Myc), proliferation (CycE) and antiapoptotic genes (Diap1), elevation of Upd-Jak-Stat signalling
Increased tissue growth (reviewed by [122])

BAP (Brahma) complex knockdown (brm, Snr1, mor, Bap111, osa) ​
Results in upregulation of Wingless (Wnt) and Dpp signalling
Neoplastic tumour overgrowth in larval wing epithelial tissue [123]

Taiman (Ecdysone Receptor coactivator) overexpression​
Results in expression of germline stem cell factors
Hyperplastic tumour overgrowth in larval wing epithelial tissue [124]

Guidance receptors

Frazzled (Dcc) loss of function and expression of the Caspase inhibitor P35
Results in an invasive phenotype in eye epithelial cells, but cells can differentiate
Inhibition of JNK signalling ​

Requires Rho1​

Invasive, but differentiated, tumours in larval/pupal eye-antennal epithelial tissues [125]

Mitotic checkpoint, chromosome instability, DNA damage repair genes

Nek2 (centrosomal kinase) overexpression​ 
​ 
​ 
​ 
​ 
RetMEN2B overexpression—elevated Ras, PI3K, Src, JNK signalling ​
  RasV12
Results in Rac1, Rho1, Wg signalling and elevated expression of Diap1, MMP1​
Results in PI3K signalling
Invasive tumours in larval eye-antennal epithelial tissue [126]

bub3 knockdown
Results in aneuploidy
p35 overexpression to block effector caspase activity​
​ 
Neoplastic overgrowth of wing epithelial cells [127]

DNA repair or DNA damage checkpoint mutants
Depletion of okra (DmRAD54) or spnA (DmRAD51) ​
(Homologous recombination of DNA double strand-breaks in G2) ​
grp (chk1) and mei-41 (ATR) knockdown​
(DNA damage checkpoint)
Ionizing irradiation and p35 overexpression​
Results in JNK activation, which leads to MMP1 and Wg upregulation
Overgrowth and cell delamination/migration in the wing epithelial tissue [128]