A B PND3 ED18.5 PND6 PND60 GCL NBL INL ONL Figure 1: Expression of Cadherin-11 in Developing Murine Retina. A) Cadherin-11 is expressed in the differentiating layer at (embryonic day) ED18.5, by migrating cells at (post natal day) PND3 and again highly expressed by cells possibly migrating to their appropriate position in the developing retina at PND6. B) By adult, (PND60) cadherin-11 expression is restricted to cell types of the INL with high expression by Müller glia processes that span the entire retina.

160 kDa Merge 40x oil CDH11 HPC-1 D B GS Merge 100x oil Cralbp A C GCL INL ONL Chx-10 40x oil 100x oil Figure 2: Co-expression of Cadherin-11 and Retinal Cell Types in Adult Retina. A, B) Cadherin-11 expression co-localizes with Müller glia cell bodies (CRALBP, 100x magnification), Müller glia cell processes (glutamine synthetase, 40x magnification) and horizontal cells (160 kDa, 40x magnification). C, D) but not with bipolar (Chx-10, 40x and 100x magnification) or amacrine (HPC-1, 40x magnification) cell types.

ED18.5 PND3 PND6 PND15 PND60 B C A GCL INL ONL Figure 3: Retinal Histology of Cdh11+/+, Cdh11+/-, and Cdh11-/- Littermates. Hematoxylin and Eosin (H&E) staining of 5 µm sections cut through the optic nerve and lens. At developmental time points, ED18.5, PND3, PND6, PND15 and PND60 (adult), no gross retinal phenotype was observed between A) Cdh11+/+, B) Cdh11+/-, and C) Cdh11-/- Littermates.

Chx-10 160kDa HPC-1 Cdh11+/+ A Cdh11-/- B C Cralbp Brd-U Cadherin-2 Supplementary Figure 1: No gross differences are revealed in differentiation of retinal cell types, proliferation or expression of cadherin-2 retinae of Cdh11+/+ Cdh11+/- and Cdh11-/- Littermate Mice. All INL cell types were assayed to detect disruptions in retinal phenotype of Cdh11+/+ vs. Cdh11-/- Littermates. Retinal cell type markers: Bipolar & progenitor (Chx-10), horizontal (160 kDa), amacrine (HPC-1) and Müller glia (CRALBP) showed no gross change at developmental time points A) ED18.5, B) PND3 and C) PND6. As well, no changes were seen in expression of S-phase cells by BrdU incorporation or cadherin-2 expression.

cadherin-11 TAg A B C Supplementary Figure 2: Gradual Loss of Cadherin-11 Expression in TAg-RB Tumors. A) At 4 weeks of age TAg-RB mice display multifocal tumors (clusters) which stain positive for SV40 T-antigen (green). Some of these multifocal tumors lose cadherin-11 expression (red) while some retain expression (magnified picture), describing a gradual loss of cadherin-11 expression in tumors at this stage. B) At 5 weeks, entire tumor regions that are positive for SV40 T-antigen are completely negative for cadherin-11 and regions of no tumor retain cadherin-11 expression (arrow). C) By 5 months of age, entire tumor area shows no cadherin-11 expression.

A C B Cdh11+/-;TAg+/- Cdh11-/-;TAg+/- Cdh11+/+; TAg+/- K-W Test: TAg+ve cells / retina (cells/pixelsx10^-4) C Ratio of Tag-positive cells to retinal area K-W Test: p=0.01* Cdh11+/-; TAg+/- Cdh11-/-; Cdh11+/+; 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 Figure 4: At PND8, Cdh11 Allelic Loss Significantly Reduces T-antigen Cell Number (cells of origin of retinoblastoma). A) Representative sections of Cdh11+/+;TAg+/-, Cdh11+/-;TAg+/-, and Cdh11-/-;TAg+/-, genotypes by H&E stain and T-Antigen DAB staining. T-antigen stains single cells in the INL of the retina and these cells are fewer in number with allele dosage of Cdh11. H&E staining amongst the three genotypes shows no major phenotypical difference. B) Manual counts of T-antigen positive cells of the retina revealed significantly less (p=0.0118) T-antigen cells (cells of origin of retinoblastoma) when each allele of Cdh11 is lost. C) To account for retinal size, a ratio of T-antigen cell numbers to total retinal area were made. This illustration reflects the same as (B), indicating a statistical trend (p=0.0078) of decreasing T-antigen positive cells when one allele of Cdh11 is lost each time. Kruskal-Wallis test was used to assess significance. Error bars represent standard deviations. B K-W Test (Total Aag + between genotypes) p=0.01* K-W Test (Retinal Size between genotypes) p=0.83

PCNA Clone PC10; Dako, Denmark Hes5 and Caspase-3 Positive cells in retinas of mice 10 20 30 40 50 60 70 80 Hes-5 Caspase-3 Number of Positively Stained Cells CDH11+/+;TAg+/- CDH11-/-;TAg+/- p = 0.3 p = 0.35 Additional Expts Done: P8: Hes 5, Caspase 3, PCNA, Cralbp PCNA Clone PC10; Dako, Denmark Supplementary Figure 3: Quantitation of Hes-5 and Activated Caspase-3 Positive Cells in Retinae of Cdh11+/+;TAg+/- and Cdh11-/-;TAg+/- mice at PND8. Cells positive for early Müller differentiating marker, Hes-5 and activated caspase-3 were counted in 3 random sections taken from 5 mice per genotype. These counts revealed no significant difference amongst genotypes with Student’s t-test p-values: p=0.3 for Hes-5 counts and p=0.35 for Caspase-3. Error bars reveal standard deviations.

Additional Expts Done: P28-PCNA Cdh11+/-;TAg+/- Cdh11-/-;TAg+/- Cdh11+/+;TAg+/- B Percent tumors in retinas of mice at PND28 % Tumor/retina [pixels] K-W Test: Cdh11+/-; TAg+/- Cdh11-/-; Cdh11+/+; 1 2 3 4 5 6 7 8 9 Figure 5: At PND28, Less Multifocal Tumors Develop When Cdh11 Alleles are Lost. A) A distinct phenotype is observed from representative sections of T-antigen DAB and H&E stains amongst the three genotypes. T-antigen DAB staining shows far less multifocal tumors present in mice with mutant Cdh11 alleles; H&E shows first signs of rosette formations in Cdh11+/+ mice describing more developed tumors in Cdh11+/+ vs. Cdh11-/- mice. B) Mice never regain normal phenotype from PND8 as number of multifocal tumors that emerge are significantly less (p=0.0167) in mice with Cdh11 allele loss. Tumor volume was calculated using image J software measuring tumor area (T-antigen stained region) as a percentage of retinal area (manually traced) of selected sections (approximately 300 µm apart) through the eye. Kruskal Wallis test was used to assess significance. Error bars represent standard deviations.

Additional Expts Done: P84-PCNA P84-Caspase-3 Cdh11+/-;TAg+/- Cdh11-/-;TAg+/- Cdh11+/+;TAg+/- Cdh11+/-; TAg+/- Cdh11-/-; Cdh11+/+; B % Tumor per retina Percent tumors in retinas of mice at PND84 K-W Test P=0.42 5 1 2 3 Figure 6: At PND84, Tumor volume in all Three Genotypes Show no Significant Difference, Describing a Trend of Faster Growing Tumors in Mice with Mutant Cdh11 Alleles. A) Representative H&E and T-antigen DAB stained sections show large tumors originating from the INL of the retina. Tumors are composed of disorganized cells, rosette formations and disrupted laminated layers due to tumor growth. No gross phenotypical difference is observed amongst the varying genotypes by H&E. B) Tumor volume in the three genotypes show no statistical difference (p=0.0935), highly suggestive of faster growing tumors in mice with Cdh11 loss, despite fewer tumors to start. Tumor volume was calculated the same as described in Figure 5. Kruskal Wallis test was used to assess significance. Error bars represent standard deviations. C) Tumor growth was calculated by a two-way ANOVA which revealed no significant correlation (p=0.0972), but a strong trend of faster growing tumors in mice with mutated Cdh11 alleles. C K-W Test (Total Retinal Volume between genotypes) p=0.07 K-W Test (Total Tumor Volume between genotypes) p=0.42

? Antibody Name Company Dilution Used SV40 Tag (Pab 101) mouse monoclonal Santa Cruz Biotechnology Cat# SC-147, Lot# A2506, 1:200 CDH11 - clone CDH113H Gift from Dr. St. John at ICOS Corp. 1:2500 CDH2 (N-cadherin) BD Biosciences Pharmigen Cat# 610920, Lot# 06247 1:2000 BrdU (purified anti-bromodeoxyuridine) Cat# 555627, Lot#52817, Progenitors and Bipolars: Chx-10 sheep polycolonal Gift from Rod Bremner, UHN 1:1000 Apoptosis: activated caspase-3: anti-h/m Caspase 3 (active) rabbit polyclonal R&D Systems Cat# AF835, Lot# CFZ326011 1:500 Early Müller Glia: Hes-5 ABCAM Cat# ab25374 1:50 Müller Glia: CRALBP Rabbit polyclonal Vimentin goat polyclonal Gift from John Saari Cat# Lot# 1:6000 1:100 Ganglion - Brn3b Cat# sc-6026 Amacrine – Syntaxin clone HPC-1 mouse monoclonal Sigma Cat# S0664 Horizontal – 160 kDa ? 1:40 Table 1: Antibody List: This table is informative of all antibodies, corresponding company names and dilutions used in this study.

C Tumor growth from PND28 - PND84 Cdh11+/-;TAg+/- Cdh11-/-;TAg+/- Fold increase tumor growth Tumor growth from PND28 - PND84 C Cdh11+/-;TAg+/- Cdh11-/-;TAg+/- Cdh11+/+;TAg+/- 2 4 6 8 10 12 Two-way ANOVA p=0.0972