The pathogenesis of penile squamous cell carcinoma (PSCC) is not well understood, though risk factors include human papillomavirus (HPV). Disruption of HER/PTEN/Akt pathway is present in many cancers; however there is little information on its function in PSCC. We investigated HER family receptors and phosphatase and tension homolog (PTEN) in HPV-positive and negative PSCC and its impact on Akt activation using immunohistochemistry and fluorescent in situ hybridisation (FISH). 148 PSCCs were microarrayed and immunostained for phosphorylated EGFR (pEGFR), HER2, HER3, HER4, phosphorylated Akt (pAkt), Akt1 and PTEN proteins. EGFR and PTEN gene status were also evaluated using FISH. HPV presence was assessed by PCR. pEGFR expression was detected significantly less frequently in HPV-positive than HPV-negative tumours (p = 0.0143). Conversely, HER3 expression was significantly more common in HPV-positive cases (p = 0.0128). HER4, pAkt, Akt and PTEN protein expression were not related to HPV. HER3 (p = 0.0054) and HER4 (p = 0.0002) receptors significantly correlated with cytoplasmic Akt1 immunostaining. All three proteins positively correlated with tumour grade (HER3, p = 0.0029; HER4, p = 0.0118; Akt1, p = 0.0001). pEGFR expression correlated with pAkt but not with tumour grade or stage. There was no EGFR gene amplification. HER2 was not detected. PTEN protein expression was reduced or absent in 62% of tumours but PTEN gene copy loss was present only in 4% of PSCCs. EGFR, HER3 and HER4 but not HER2 are associated with penile carcinogenesis. HPV-negative tumours tend to express significantly more pEGFR than HPV-positive cancers and this expression correlates with pAkt protein, indicating EGFR as an upstream regulator of Akt signalling in PSCC. Conversely, HER3 expression is significantly more common in HPV-positive cases and positively correlates with cytoplasmic Akt1 expression. HER4 and PTEN protein expression are not related to HPV infection. Our results suggest that PSCC patients could benefit from therapies developed to target HER receptors.

Aims To determine whether Ki-67 immunoexpression in penile squamous cell carcinoma (PSCC) has a prognostic value and correlates with lymph node metastasis, human papillomavirus (HPV) infection and patient survival. Methods 148 formalin-fixed paraffin-embedded PSCC samples were tissue-microarrayed, including 97 usual-type SCCs, 17 basaloid, 15 pure verrucous carcinomas, 2 warty and 17 mixed-type tumours. All samples were immunostained for Ki-67 protein. HPV DNA was detected with INNO-LiPA assay. Follow-up data were available for 134 patients. Results Ki-67 was strongly expressed in 57/148 (38.5%) of PSCCs. Different cancer subtypes showed significant difference in Ki-67 expression (p<0.0001) with highest positivity in basaloid, 16/17 (94%), followed by usual type, 38/97 (39%) and lack of Ki-67 positive cases within verrucous tumours, 0/15. Ki-67 positively correlated with high-risk HPV (p<0.0001) and showed good specificity (84%) but low sensitivity (61%) for high-risk HPV detection. Ki-67 protein strongly positively correlated with tumour grade (p<0.0001) but not with stage (p=0.2193), or lymph node status (p=0.7366). Ki-67 showed no prognostic value for cancer-specific survival (HR=1.00, 95%, CI 0.99 to 1.02, p=0.54) or overall survival (HR=1.00, 95%, CI 0.99 to 1.02, p=0.45). High tumour stage, lymph node metastasis, high tumour grade and age at diagnosis were all independent prognostic factors for cancer-specific survival and overall survival. Conclusions Ki-67 is only a moderate surrogate marker for HPV infection in PSCC. It does not show prognostic value for cancer-specific survival and overall survival in PSCC.

Stankiewicz E, Prowse D M, Ktori E, Cuzick J, Ambroisine L, Zhang X, Kudahetti S, Watkin N, Corbishley C & Berney D M (2011) Histopathology58, 433–439 The retinoblastoma protein/p16^INK4Apathway but not p53 is disrupted by human papillomavirus in penile squamous cell carcinomaAims:  The pathogenesis of penile squamous cell carcinoma (PSCC) is not well understood. Human papillomavirus (HPV) may be involved in carcinogenesis, but few studies have compared cell‐cycle protein expression in HPV positive and negative cancers. The aim was to determine the extent of HPV infection in different histological subtypes of PSCC and its impact on the expression of key cell‐cycle proteins: p53, p21, p16^INK4A and retinoblastoma (RB) protein.Methods and results:  One hundred and forty‐eight PSCC samples were examined immunohistochemically for RB, p16^INK4A, p53 and p21 protein expression. One hundred and two cases were typed for HPV by PCR. HPV DNA was detected in 56% of tumours, with HPV16 present in 81%. Basaloid tumours were related strongly to HPV infection (10 of 13), while verrucous were not (three of 13). Fifty‐nine per cent (38 of 64) of usual type SCCs had HPV infection. RB protein correlated negatively (P < 0.0001) and p16^INK4A (P < 0.0001) and p21 (P = 0.0002) correlated positively with HPV infection. p53 did not correlate with HPV infection.Conclusions:  HPV infection is present in more than half of penile cancers and it is responsible for RB pathway disruption. However, no link between HPV and p53 immunodetection was found. Only basaloid and half of usual‐type PSSCs correlate with HPV infection, confirming possible separate aetiologies for those tumours.

Next-generation sequencing of primary tumors is now standard for transcriptomic studies, but microarray-based data still constitute the majority of available information on other clinically valuable samples, including archive material. Using prostate cancer (PC) as a model, we developed a robust analytical framework to integrate data across different technical platforms and disease subtypes to connect distinct disease stages and reveal potentially relevant genes not identifiable from single studies alone. We reconstructed the molecular profile of PC to yield the first comprehensive insight into its development, by tracking changes in mRNA levels from normal prostate to high-grade prostatic intraepithelial neoplasia, and metastatic disease. A total of nine previously unreported stage-specific candidate genes with prognostic significance were also found. Here, we integrate gene expression data from disparate sample types, disease stages and technical platforms into one coherent whole, to give a global view of the expression changes associated with the development and progression of PC from normal tissue through to metastatic disease. Summary and individual data are available online at the Prostate Integrative Expression Database (PIXdb), a user-friendly interface designed for clinicians and laboratory researchers to facilitate translational research.