Ki-67 expression predicts radiosensitivity in oral squamous cell carcinoma

Histopathologic Changes after Yttrium-90 Radioembolization of Colorectal Liver Metastases: A Pilot Feasibility Study

PURPOSE

To evaluate the histopathologic changes and potential correlations of tumor absorbed dose (TAD) after yttrium-90 transarterial radioembolization (TARE) for colorectal liver metastases (CLMs).

MATERIALS AND METHODS

This prospective pilot study assessed 12 patients with 13 CLMs through positron emission tomography (PET)/computed tomography (CT)-guided biopsies before, immediately after TARE (T0), and 3 weeks after TARE (T3). Subsequent sampling from the same location was enabled by fiducial placement. Biopsy samples were evaluated with hematoxylin and eosin, TUNEL, Ki67, OxPhos, caspase-3 (CC3), and pH2AX antibodies. Proliferation changes (Ki67) and double-strand DNA breaks (DSBs) were evaluated quantitatively. TAD was calculated on post-TARE PET/CT scan of the biopsy needle location at T0 and T3.

RESULTS

Median TAD at 3 weeks after TARE was 162 Gy (interquartile range (IQR), 92-211 Gy). DSBs decreased significantly from T0 (median, 77%; IQR, 75%-100%) to T3 (median, 14%; IQR, 0%-54%; P = .028). A decrease in Ki67 was also documented (median, 73%; IQR, 70%-80% at T0 vs median, 41%; IQR, 0%-66% at T3; P = .046). There was a strong positive correlation between TAD and DSBs at T0 (r[9] = 0.68) and a strong negative correlation at T3 (r[10] = -0.855; P = .042 and P = .002, respectively). There was a strong negative correlation between TAD and Ki67 at both T0 (r[9] = -0.733; P = .025) and T3 (r[10] = -0.681; P = .030). Tumors that exhibited caspase-3 activation (8/13, 62%) at either T0 or T3 time point were more likely to develop progression (7/8 [88%] vs 1/5 [20%]; P = .015).

CONCLUSIONS

Post-TARE biopsy can be used to assess TAD and histopathologic changes. Significant decreases in DSBs and proliferation index were noted after TARE. Post-TARE CC3 activation deserves further exploration.

Tumor-matched and unmatched cancer associated fibroblasts exhibit differential effect on proliferation and FMOD and MMP9 gene expression in head and neck squamous cell carcinoma cells when cocultured in spheroids

BACKGROUND

Cancer-associated fibroblasts (CAFs) are the major cellular component of the tumor microenvironment and are known to affect tumor growth and response to various treatments. This study was undertaken to investigate the crosstalk between tumor-matched or unmatched CAFs and head and neck squamous cell carcinoma (HNSCC) cells regarding tumor growth and treatment response.

METHODS

Three HNSCC cell lines (LK0412, LK0902 and LK0923), were cocultured in 2D or in 3D with their tumor-matched CAFs, site matched CAFs from other tumors or normal oral fibroblasts (NOFs). Cell proliferation was assessed as the amount of Ki67 positive cells/ spheroid area in formalin-fixed- paraffin-embedded 3D spheroids stained with Ki67 antibody. Viability after seven days of cisplatin treatment was measured with CellTiter-Glo 3D Viability Assay. The mRNA expression of CAF-associated markers (ACTA2, COL1A2, FAP, PDGFRα, PDGFRβ, PDPN, POSTN and S100A4) in CAFs before and after coculture with tumor cells as well as mRNA expression of CAF-induced genes (MMP1, MMP9 and FMOD) in tumor cells separated from CAFs after co-culture was measured with RT-qPCR. The expression of selected protein biomarkers was validated with immunohistochemistry based on previous mRNA expression results.

RESULTS

The proliferation of the LK0412 and LK0902 tumor spheroids varied significantly when cocultured with different CAFs and NOFs as shown by Ki-67 positive cells. RT‒qPCR analysis revealed different molecular profile of the analyzed HNSCC-derived CAFs concerning the expression of CAF-associated markers. The interaction between CAFs and HNSCC cells was more pronounced after coculture with unmatched CAFs as shown by changes in mRNA expression pattern of CAF-specific markers. Additionally, the unmatched CAFs significantly upregulated the mRNA expression of MMP1, MMP9 and FMOD in tumor cells compared to tumor-matched CAFs.

CONCLUSION

Our results indicate that tumor-matched CAFs are unique for each tumor and affect the proliferation and the gene/protein expression of tumor cells in a distinct manner. The interaction between tumor unmatched CAFs and HNSCC cells in the tumor spheroids is associated with significant changes in the mRNA expression of CAF-specific markers and significant increases in FMOD and MMP9 in tumor cells compared to when cocultured with tumor-matched CAFs. Taken together, our results show how important the selection of CAFs is to get a reliable in vitro model that mimics the patients' tumor.

[French national standard for the treatment of squamous cell carcinoma of upper aero-digestive tract - General principles of treatment]

OBJECTIVES

The management of upper aerodigestive tract cancers is a complex specialty. It is essential to provide an update to establish optimal care. At the initiative of the INCa and under the auspices of the SFORL, the scientific committee, led by Professor Béatrix Barry, Dr. Gilles Dolivet, and Dr. Dominique De Raucourt, decided to develop a reference framework aimed at defining, in a scientific and consensus-based manner, the general principles of treatment for upper aerodigestive tract cancers applicable to all sub-locations.

METHODOLOGY

To develop this framework, a multidisciplinary team of practitioners was formed. A systematic analysis of the literature was conducted to produce recommendations classified by grades, in accordance with the standards of the French National Authority for Health (HAS).

RESULTS

The grading of recommendations according to HAS standards has allowed the establishment of a reference for patient care based on several criteria. In this framework, patients benefit from differentiated care based on prognostic factors they present (age, comorbidities, TNM status, HPV status, etc.), conditions of implementation, and quality criteria for indicated surgery (operability, resectability, margin quality, mutilation, salvage surgery), as well as quality criteria for radiotherapy (target volume, implementation time, etc.). The role of medical and postoperative treatments was also evaluated based on specific criteria. Finally, supportive care must be organized from the beginning and throughout the patients' care journey.

CONCLUSION

All collected data have led to the development of a comprehensive framework aimed at harmonizing practices nationally, facilitating decision-making in multidisciplinary consultation meetings, promoting equality in practices, and providing a state-of-the-art and reference practices for assessing the quality of care. This new framework is intended to be updated every 5 years to best reflect the latest advances in the field.

Clinicopathologic features of conjunctival MALT lymphomas refractory to radiation therapy

OBJECTIVE

Clinicopathologic features of patients with limited-stage mucosa-associated lymphoid tissue (MALT) lymphoma refractory to radiotherapy have not been fully elucidated. This study aimed to elucidate clinicopathologic features of localized conjunctival MALT lymphoma concerning radiosensitivity by analyzing cell proliferation and expression of mismatch repair proteins.

METHODS

We enrolled 26 patients with localized conjunctival MALT lymphoma treated with radiotherapy from November 2007 to March 2020. Monoclonal immunoglobulin H gene rearrangement was tested in addition to histopathologic evaluation. Thirty-six specimens were immunostained with antibodies to Ki-67 and MutL protein homologue 1 (MLH1), MutS protein homologue 2 (MSH2), and MutS protein homologue 6 (MSH6). Positive rates under a high-power field at a hot spot were counted manually.

RESULTS

After radiotherapy, 21 patients showed clinical disappearance of the tumour without recurrence (effective group). Three patients showed temporary disappearance of the tumour, which later recurred (relapse group). Two patients did not show disappearance of the tumour (ineffective group). The 2 ineffective patients were young, had bilateral lesions, and received x-ray beam therapy. The mean positive rates of Ki-67, MLH1, MSH2, and MSH6 were higher in tumours with complete remission (CR) than in those without CR (23.4% ± 4.0% and 18.7& ± 4.7%, 14.7% ± 2.3% and 7.1% ± 3.7%, 23.9% ± 4.7% and 14.4% ± 5.2%, and 11.5% ± 3.2% and 5.4% ± 2.2%; p > 0.05 for each, respectively).

CONCLUSIONS

A few patients could not achieve CR following radiotherapy, whereas there were no significant differences in proliferation activity and mismatch repair proteins between tumours with and without CR.

Energy Metabolism Is Altered in Radioresistant Rectal Cancer

Resistance to neoadjuvant chemoradiation therapy is a significant clinical challenge in the management of rectal cancer. There is an unmet need to identify the underlying mechanisms of treatment resistance to enable the development of biomarkers predictive of response and novel treatment strategies to improve therapeutic response. In this study, an in vitro model of inherently radioresistant rectal cancer was identified and characterized to identify mechanisms underlying radioresistance in rectal cancer. Transcriptomic and functional analysis demonstrated significant alterations in multiple molecular pathways, including the cell cycle, DNA repair efficiency and upregulation of oxidative phosphorylation-related genes in radioresistant SW837 rectal cancer cells. Real-time metabolic profiling demonstrated decreased reliance on glycolysis and enhanced mitochondrial spare respiratory capacity in radioresistant SW837 cells when compared to radiosensitive HCT116 cells. Metabolomic profiling of pre-treatment serum samples from rectal cancer patients (n = 52) identified 16 metabolites significantly associated with subsequent pathological response to neoadjuvant chemoradiation therapy. Thirteen of these metabolites were also significantly associated with overall survival. This study demonstrates, for the first time, a role for metabolic reprograming in the radioresistance of rectal cancer in vitro and highlights a potential role for altered metabolites as novel circulating predictive markers of treatment response in rectal cancer patients.

Predicting the Proliferation of Tongue Cancer With Artificial Intelligence in Contrast-Enhanced CT

Tongue squamous cell carcinoma (TSCC) is the most common oral malignancy. The proliferation status of tumor cells as indicated with the Ki-67 index has great impact on tumor microenvironment, therapeutic strategy making, and patients’ prognosis. However, the most commonly used method to obtain the proliferation status is through biopsy or surgical immunohistochemical staining. Noninvasive method before operation remains a challenge. Hence, in this study, we aimed to validate a novel method to predict the proliferation status of TSCC using contrast-enhanced CT (CECT) based on artificial intelligence (AI). CECT images of the lesion area from 179 TSCC patients were analyzed using a convolutional neural network (CNN). Patients were divided into a high proliferation status group and a low proliferation status group according to the Ki-67 index of patients with the median 20% as cutoff. The model was trained and then the test set was automatically classified. Results of the test set showed an accuracy of 65.38% and an AUC of 0.7172, suggesting that the majority of samples were classified correctly and the model was stable. Our study provided a possibility of predicting the proliferation status of TSCC using AI in CECT noninvasively before operation.

RNA sequencing of glioblastoma tissue slice cultures reveals the effects of treatment at the transcriptional level

One of the major challenges in cancer research is finding models that closely resemble tumors within patients. Human tissue slice cultures are a promising approach to provide a model of the patient's tumor biology ex vivo. Recently, it was shown that these slices can be successfully analyzed by whole transcriptome sequencing as well as automated histochemistry, increasing their usability as preclinical model. Glioblastoma multiforme (GBM) is a highly malignant brain tumor with poor prognosis and little is known about its genetic background and heterogeneity regarding therapy success. In this study, tissue from the tumors of 25 patients with primary GBM was processed into slice cultures and treated with standard therapy (irradiation and temozolomide). Total RNA sequencing and automated histochemistry were performed to enable analysis of treatment effects at a transcriptional and histological level. Slice cultures from long‐term survivors (overall survival [OS] > 24 months) exhibited more apoptosis than cultures from patients with shorter OS. Proliferation within these slices was slightly increased in contrast to other groups, but not significantly. Among all samples, 58 protein‐coding genes were upregulated and 32 downregulated in treated vs. untreated slice cultures. In general, an upregulation of DNA damage‐related and cell cycle checkpoint genes as well as enrichment of genotoxicity pathways and p53‐dependent signaling was found after treatment. Overall, the current study reproduces knowledge from former studies regarding the feasibility of transcriptomic analyses and automated histology in tissue slice cultures. We further demonstrate that the experimental data merge with the clinical follow‐up of the patients, which improves the applicability of our model system.

Ki-67 labeling index as a prognostic marker in advanced stomach cancer

Purpose

Proliferation marker Ki-67 is widely used in cancer prognosis prediction. We tried to investigate the role of Ki-67 as a prognostic factor in stomach cancer after surgery in this study.

Methods

We retrospectively evaluated 251 patients who underwent curative resection for gastric cancer from 2010 to 2015. In pathologic examination, Ki-67 labeling index was defined as the percentage of Ki-67 antigen positive cells. Prognostic significance of Ki-67 for gastric cancer was evaluated. Disease-free survival (DFS) was assessed as a primary end-point.

Results

The median follow-up period was 28.0 months. Thirty-one patients (12.4%) showed Ki-67 labeling index (LI) lower than 25%. Sixty-eight patients (26.6%) showed recurrence during follow-up period. Recurrence was associated with Ki-67 LI level (≤25%, P = 0.016), and lymph node metastasis status (P = 0.002). High Ki-67 LI level (>25%) was also related to p53 positivity (P < 0.001) and poorly cohesive type (P = 0.002). The 3-year DFS was 69.4%. Low Ki-67 LI level (≤25%) was related with low DFS (47.6% vs. 72.6%, P = 0.016). T stage (P < 0.001), N stage (P = 0.006), lymphovascular invasion (P = 0.010), and neuronal invasion (P = 0.001) also affected the DFS. In addition, T stage (P = 0.03) and Ki-67 LI (P = 0.035) were independent prognostic factors for DFS. In patients treated with adjuvant chemotherapy (n = 239, 93.4%), low Ki-67 (≤25%) was a poor prognostic factor for DFS (P = 0.013).

Conclusion

Low Ki-67 LI predicts high rate of progression and low DFS of stomach cancer. Ki-67 LI can be a predictive marker in resected stomach cancer treated with surgery and adjuvant chemotherapy.

Combined Ki67 and ERCC1 for prognosis in non-keratinizing nasopharyngeal carcinoma underwent chemoradiotherapy

This study aimed to assess the predictive value of combined Ki67 and ERCC1 in distant metastasis-free nasopharyngeal carcinoma. 334 such cases were retrospectively assessed. Immunohistochemistry was used to evaluate Ki67 and ERCC1 protein levels in tumor tissues. Associations of Ki67 and ERCC1 amounts with clinical characteristics and survival were analyzed. Medium follow-up was 48.7 months; overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS) were 91.3%, 76.0%, 82.0%, and 91.9%, respectively. High Ki67 expression was found in 35.6% patients, and positively correlated with clinical- and N- staging (P = 0.005, P < 0.001); 4-year OS, DFS, and DMFS were significantly lower in the high Ki67 group than patients with low-medium expression (P = 0.001, P = 0.012, P = 0.007). High ERCC1 expression was found in 35.3% of patients, and positively correlated with clinical- and T- staging. Compared with low ERCC1 expression cases, 4-year OS, DFS, DMFS, and LRFS were decreased significantly in those with high levels. High Ki67 and ERCC1 levels were related to adverse prognoses of OS (HR=4.977, 95% CI 2.31–12.292, P<0.001), DFS (HR = 4.178, 95% CI 2.421–7.212, P < 0.001), DMFS (HR = 3.722, 95% CI 2.028–7.015, P < 0.001), and LRFS (HR = 3.689, 95% CI 1.423–9.566, P = 0.007). Compared with the low-medium Ki67 and low ERCC1 groups, no significant difference in survival prognosis was obtained in the low-medium Ki67 and high ERCC1 groups, and patients with high Ki67 and low ERCC1 levels. Combined Ki67 and ERCC1 can better predict nasopharyngeal carcinoma prognosis than individual parameters.

Fusion between M2-macrophages and cancer cells results in a subpopulation of radioresistant cells with enhanced DNA-repair capacity

Cell fusion is a natural biological process in normal development and tissue regeneration. Fusion between cancer cells and macrophages results in hybrids that acquire genetic and phenotypic characteristics from both maternal cells. There is a growing body of in vitro and in vivo data indicating that this process also occurs in solid tumors and may play a significant role in tumor progression. However, investigations of the response of macrophage:cancer cell hybrids to radiotherapy have been lacking. In this study, macrophage:MCF-7 hybrids were generated by spontaneous in vitro cell fusion. After irradiation, both hybrids and their maternal MCF-7 cells were treated with 0 Gy, 2.5 Gy and 5 Gy γ-radiation and examined by clonogenic survival and comet assays at three time points (0 h, 24 h, and 48 h). Compared to maternal MCF-7 cells, the hybrids showed increased survival fraction and plating efficiency (colony formation ability) after radiation. The hybrids developed less DNA-damage, expressed significantly lower residual DNA-damage, and after higher radiation dose showed less heterogeneity in DNA-damage compared to their maternal MCF-7 cells. To our knowledge this is the first study that demonstrates that macrophage:cancer cell fusion generates a subpopulation of radioresistant cells with enhanced DNA-repair capacity. These findings provide new insight into how the cell fusion process may contribute to clonal expansion and tumor heterogeneity. Furthermore, our results provide support for cell fusion as a mechanism behind the development of radioresistance and tumor recurrence.

Correlation between the Ki-67 proliferation index and response to radiation therapy in small cell lung cancer

Background

In the breast cancer, the decision whether to administer adjuvant therapy is increasingly influenced by the Ki-67 proliferation index. In the present retrospective study, we investigated if this index could predict the therapeutic response to radiation therapy in small cell lung cancer (SCLC).

Methods

Data from 19 SCLC patients who received thoracic radiation therapy were included. Clinical staging was assessed using the TNM classification system (UICC, 2009; cstage IIA/IIB/IIIA/IIIB = 3/1/7/8). Ki-67 was detected using immunostained tumour sections and the Ki-67 proliferation index was determined using e-Count software. Radiation therapy was administered at total doses of 45–60 Gy. A total of 16 of the 19 patients received chemotherapy.

Results

Patients were divided into two groups, one with a Ki-67 proliferation index ≥79.77% (group 1, 8 cases) and the other with a Ki-67 proliferation index <79.77% (group 2, 11 cases). Following radiation therapy, a complete response (CR) was observed in six cases from group 1 (75.0%) and three cases from group 2 (27.3%). The Ki-67 proliferation index was significantly correlated with the CR rate (P = 0.05), which was significantly higher in group 1 than in group 2 (P = 0.04). The median survival time was 516 days for all patients, and the survival rates did not differ significantly between groups 1 and 2.

Conclusions

Our study is the first to evaluate the correlation between the Ki-67 proliferation index and SCLC tumour response to radiation therapy. Our findings suggest that a high Ki-67 proliferation index might represent a predictive factor for increased tumour radiosensitivity.

Apoptosis and Ki-67 as predictive factors for response to radiation therapy in feline nasal lymphomas

Nasal lymphoma is the most common nasal tumor in cats and is generally a solitary and radiosensitive tumor. We retrospectively evaluated the response to radiation and survival time in relation to apoptosis and Ki-67 indices in feline nasal lymphomas treated with radiation therapy. The apoptotic and Ki-67 indices were evaluated with TUNEL and immunohistochemical staining in 30 biopsy tissues that were taken before any treatment. These two indices were compared, and differences between different treatment response groups were analyzed. The correlation between the median survival times (MST) and the indices was estimated using the Kaplan Meier method, and statistical differences between survival curves were analyzed using a log-rank method. With regard to apoptotic index, a statistical difference was observed between the samples taken from cats with complete response and stable disease (1.22% vs. 0.45%; P=0.045). The Ki-67 index in cats with both complete response and partial response was significantly higher than in cats with stable disease (44.4% and 39.6% vs. 16.3%; P<0.001 and P=0.008, respectively). The cats with a high level of apoptosis (>0.9%) nasal lymphoma were not significantly prolonged MSTs (P=0.202), however, high Ki-67-positive (>40%) cats experienced a statistically significant relationship with longer survival time (P=0.015). Our results indicate that spontaneous apoptotic and Ki-67 indices are strong predictors for response to radiation therapy in feline nasal lymphomas.

What is the Prognostic Significance of Ki-67 Positivity in Oral Squamous Cell Carcinoma?

BACKGROUD

Numerous studies have stated that Ki-67 is a good prognostic marker in oral squamous cell carcinoma (OSCC). However, some researchers believe the contrary. To address this controversy, we performed a systematic literature retrieval to estimate the prognostic significance of Ki-67 expression in patients with OSCC.

METHODS

Databases covering Pubmed, Ovid, Web of Science, Embase and the Cochrane library were searched regardless of publication year. Overall survival (OS), local recurrence (LR) and disease-free survival (DFS) were the main outcome measures. Relative risks (RRs) and its 95% confidential intervals (CIs) were used for statistical analysis.

RESULTS

Twenty-seven articles with 2146 patients were included in this study. The results of the meta-analysis suggested that the pooled RRs and its CIs for OS, LR, and DFS were 1.45 (1.15 - 1.84), 1.76 (0.74 - 4.16) and 1.52 (1.07 - 2.14), respectively. However, the heterogeneities of OS and LR were obvious (I-squared (OS) = 59.4%, I-squared (LR) = 72.6%). After subgroup analysis based on systemic treatment, the cut-off value of Ki-67 expression, ethnicity and types of antibody, the heterogeneities became acceptable. It was observed that systemic treatment, cut-off values of Ki-67 expression, ethnicity and the types of antibody affected the results. The statistical analyses of subgroups suggested that non-systemic treatment, (OR=1.77, 95% CI = 1.39-2.25, p = 0.000) and Asian populations (OR=2.09, 95% CI = 1.32-3.32, p = 0.002) are high risks for Ki-67 high expression, and low cut-off value of Ki-67 expression (OR = 1.44, 95% CI = 1.001-2.072), MIB-1 antibody (OR = 1.48, OR 95% = 1.10-1.99) might affect the identification of results.

CONCLUSIONS

According to this meta-analysis, high Ki-67 expression might be a negative prognostic marker of patients with OSCC, especially in Asian populations. In addition, Ki-67 expression affects the treatment response.

Forty-six cases of nasopharyngeal carcinoma treated with 50 Gy radiotherapy plus hematoporphyrin derivative: 20 years of follow-up and outcomes from the Sun Yat-sen University Cancer Center

BACKGROUND

With the improved overall survival (OS) of nasopharyngeal carcinoma (NPC) patients, the importance of quality of life (QoL) is increasingly being recognized. For some radiosensitive NPC patients, whether low-dose radiotherapy can improve the QoL without affecting clinical efficacy is unknown. This study aimed to assess the survival rates and QoL of NPC patients treated with 50 Gy radiotherapy plus hematoporphyrin derivative (HPD).

METHODS

Forty-six newly diagnosed NPC patients treated with 50 Gy radiotherapy plus HPD between June 1988 and July 1992 were analyzed. All patients were restaged according to the 7th edition of the American Joint Committee on Cancer staging system. The radiotherapy plan was designed on the basis of pretreatment computed tomography. The OS, local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS) rates were estimated using the Kaplan-Meier method. QoL was assessed using the Late Radiation Morbidity Scoring Criteria of the Radiation Therapy Oncology Group.

RESULTS

The 5-year OS, LRFS, DMFS, and DFS rates were 74.3%, 72.6%, 82.1%, and 61.2%, respectively. The corresponding 10-year rates were 38.4%, 62.9%, 78.5%, and 49.8%, respectively, and the 20-year rates were 27.7%, 51.4%, 78.5%, and 40.7%, respectively. None of the patients developed severe radiation-related complications, such as radiation-induced temporal lobe necrosis, hearing loss, trismus, and dysphagia.

CONCLUSION

Some NPC patients were sensitive to 50 Gy radiotherapy plus HPD, and this sensitivity was characterized by long-term survival without significant late treatment morbidities.

High nuclear SOX2 expression is associated with radiotherapy response in small (T1/T2) oral squamous cell carcinoma

OBJECTIVE

Expression of the stem cell transcription factor SOX2 is often used to imply stemness and poor prognosis in cancer. However, its role in oral squamous cell carcinoma (OSCC) is not fully elucidated.

MATERIAL AND METHODS

Tumour tissues from 62 patients with primary, node negative and non-metastatic OSCCs were used to evaluate SOX2 expression by immunohistochemistry. The results were correlated to clinicopathology, treatment and disease recurrences.

RESULTS

The majority of the OSCCs (88%) expressed SOX2. Patients with higher nuclear SOX2 staining intensity in the invasive front compared to the adjacent normal epithelium, had a remarkable longer disease-free period if they received adjuvant post-operative radiotherapy (P = 0.001). This was in particular evident for highly differentiated OSCCs, as none of the high SOX2-expressing tumours reoccurred in contrast to all low SOX2-expressing OSCCs.

CONCLUSIONS

High nuclear SOX2 expression in the invasive front was associated with dramatic longer disease-free period than low SOX2-expressing carcinomas after post-operative radiotherapy in small OSCCs. The result suggested that high nuclear SOX2 expression at the invasive front may predict radiosensitivity.

Prognostic utility of apoptosis index, Ki-67 and survivin expression in dogs with nasal carcinoma treated with orthovoltage radiation therapy

Apoptosis, Ki-67 and survivin expression have been reported as prognostic values in human cancer treated with radiation therapy. The aim of this study was to evaluate the correlation between the outcome of canine nasal carcinomas treated with radiation therapy and these cancer markers. The apoptotic index (AI) was evaluated with TUNEL assays, and an immunohistochemical evaluation was performed on Ki-67 and survivin in 33 biopsy samples taken before treatment. Median survival times were estimated using Kaplan-Meier curves and the log-rank method. The AI ranged from 0 to 0.7%, and the percentage of Ki-67-positive cells defined as the proliferative index (PI) ranged from 0.8 to 77% in all samples. Neither the AI nor the PI had a significant relationship with survival time (P=0.056 and 0.211). Survivin expression was detected in 84.9% of samples of canine nasal carcinoma. Dogs with high survivin expression were associated with poorer response to treatment and had shorter survival times (P=0.017 and 0.031). Advanced-stage tumors were also significantly associated with a high level of survivin (P=0.026). Overexpression of survivin was shown to be an unfavorable prognostic factor in dogs with nasal carcinomas treated with radiation therapy.