Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth... more Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth cause of cancer death in Chile. Human papillomavirus (HPV) is responsible for most cervical cancers. Individuals seeking basic information about HPV frequently turn to health information websites. We hypothesized that some of their data may be inaccurate. Study design: Comparative analysis of information. Methods: We analyze the content of highly accessed websites such as the Spanish version of Wikipedia and Yahoo Answers through the application of a questionnaire, as well as a website managed by the Chilean Ministry of Health (Minsal). The accuracy of each answer was confirmed by comparison with information retrieved from articles published by indexed journals. Results: The information provided by the Spanish version of Wikipedia was accurate; nevertheless a few omissions were detected. The quality of the information provided by the Spanish version of Yahoo Answers was inaccurate and confusing. The Minsal website lacked important information on several topics about HPV even though it is managed and endorsed by the government.
Bladder cancer (BC) is the sixth most common cause of cancer; BC risk increases with age and is m... more Bladder cancer (BC) is the sixth most common cause of cancer; BC risk increases with age and is more common among men than women. Upon diagnosis, the 5-year relative survival rate for patients is approximately 77%. The treatment options available for bladder cancer include chemotherapy, radiation therapy, immunotherapy, targeted therapy, and surgery. Despite the advances in therapeutically novel approaches, BC remains an important problem of public health. Long non-coding RNA (lncRNA) is defined as non-protein-coding RNA molecule longer than 200 nucleotides. Recent findings have highlighted that lncRNA contributes to the regulation of multiple signaling pathways in bladder cancer, suggesting that lncRNA exerts its roles during the biological processes of tumorigenesis, tumor proliferation, differentiation, apoptosis, invasion, migration, and stemness. In our laboratory, we described a family of mitochondrial long non-coding RNAs containing stem-loop structures, named sense and antis...
Background We have previously shown a differential expression of a family of mitochondrial ncRNAs... more Background We have previously shown a differential expression of a family of mitochondrial ncRNAs in normal and cancer cells. Normal proliferating cells and cancer cells express the sense mitochondrial ncRNA (SncmtRNA). In addition, while normal proliferating cells express two antisense mitochondrial ncRNAs (ASncmtRNAs-1 and −2), these transcripts seem to be universally down-regulated in cancer cells. In situ hybridization (ISH) of some normal and cancer tissues reveals nuclear localization of these transcripts suggesting that they are exported from mitochondria. Methods FISH and confocal microscopy, in situ digestion with RNase previous to ISH and electron microscopy ISH was employed to confirm the extra-mitochondrial localization of the SncmtRNA and the ASncmtRNAs in normal proliferating and cancer cells of human and mouse. Results In normal human kidney and mouse testis the SncmtRNA and the ASncmtRNAs were found outside the organelle and especially localized in the nucleus associated to heterochromatin. In cancer cells, only the SncmtRNA was expressed and was found associated to heterochromatin and nucleoli. Conclusion The ubiquitous localization of these mitochondrial transcripts in the nucleus suggests that they are new players in the mitochondrial-nuclear communication pathway or retrograde signaling. Down regulation of the ASncmtRNAs seems to be an important step on neoplastic transformation and cancer progression.
Mitochondria are traditionally been viewed as the cell's powerhouse, generating most of its ATP. ... more Mitochondria are traditionally been viewed as the cell's powerhouse, generating most of its ATP. However, besides this fundamental metabolic role, mitochondria are implicated in diverse other processes, including apoptosis, inflammation and metastasis. These functions are exerted in part by the growing class of long noncoding mitochondrial RNAs (lncmtRNAs). We found that normal human proliferating cells express a family of noncoding mitochondrial RNAs (ncmtRNAs), comprised of sense (SncmtRNA) and antisense (ASncmtRNA). However, tumor cells express only sense transcripts, suggesting that ASncmtRNA downregulation as a cancer new hallmark. The few ASncmtRNAs copies in tumor cells seem essential to tumor cell viability: knockdown of these transcripts with antisense oligonucleotides (ASO) causes massive apoptotic death of tumor cells, preceded by cell cycle arrest. Preclinical assays show that systemic administration of ASO delayed tumor growth in melanoma and renal cancer models and, caused total remission in subcutaneous renal cancer tumors. The same treatment, however, does not affect normal tissue, suggesting this approach for the development of an efficient and safe therapeutic strategy for several cancer types.
Objective: Cervical cancer is the second most common cancer in women with high rates of mortality... more Objective: Cervical cancer is the second most common cancer in women with high rates of mortality worldwide. Cervical cancer is slowly progressive and is preceded by pre-invasive intraepithelial lesions. Therefore, detection of premalignant lesions is key to preventing disease progression to advanced stages. The objective of the present study was examination and quantification of the differentially expressed non-coding mitochondrial RNAs during progression of disease. Material and methods: The differential expression of S-ncmtRNA and AS-ncmtRNA was analyzed by in situ hybridization (ISH) using tissue macroarrays (TMA) from normal, CIN1, CIN2, CIN3 and invasive squamous carcinoma (SCC). PCNA and p16INK-4a were detected in consecutive biopsies by immunohistochemistry. Quantification of ISH signal was carried out with Image ProPlus 6.1 software and the results were expressed as percentage of Integrated Optical Density (IOD). Results: We found a marked down-regulation of AS-ncmtRNA in 95% of tissues analyzed (CIN 1/2, CIN 3, and invasive squamous cancer). Moreover, differential expression of ASncmtRNA v/s S-ncmtRNA showed significant difference. Normal proliferating tissues did not display down-regulation of AS-ncmtRNA. Down regulation of AS-ncmtRNA correlated with the expression of the tumor suppressor protein p16INK-4a Conclusions: We found down-regulation of AS-ncmtRNA in pre-malignant and tumor samples which could distinguish normal tissues from early lesions and tumor samples. These results suggest that the down-regulation of AS-ncmtRNA is a novel marker of early lesions and cervix neoplasia.
Background We have previously shown a differential expression of a family of mitochondrial ncRNAs... more Background We have previously shown a differential expression of a family of mitochondrial ncRNAs in normal and cancer cells. Normal proliferating cells and cancer cells express the sense mitochondrial ncRNA (SncmtRNA). In addition, while normal proliferating cells express two antisense mitochondrial ncRNAs (ASncmtRNAs-1 and −2), these transcripts seem to be universally down-regulated in cancer cells. In situ hybridization (ISH) of some normal and cancer tissues reveals nuclear localization of these transcripts suggesting that they are exported from mitochondria. Methods FISH and confocal microscopy, in situ digestion with RNase previous to ISH and electron microscopy ISH was employed to confirm the extra-mitochondrial localization of the SncmtRNA and the ASncmtRNAs in normal proliferating and cancer cells of human and mouse. Results In normal human kidney and mouse testis the SncmtRNA and the ASncmtRNAs were found outside the organelle and especially localized in the nucleus associ...
Amplification of RNA from human sperm heads yielded a fragment of 435 bp that shares 100 % identi... more Amplification of RNA from human sperm heads yielded a fragment of 435 bp that shares 100 % identity with a central region of the 16S mitochondrial rRNA. The nuclear localization in the sperm of the mitochondrial RNA was confirmed by in-situ hybridization. These results, together with the localization of the 16S mitochondrial rRNA in mouse sperm, are the first demonstration that the organelle transcript is a normal component of the mammalian gamete. The possibility that the nuclear mitochondrial RNA arises from nuclear transcription of a mitochondrial pseudogene was ruled out. To determine when during spermatogenesis the mitochondrial RNA is localized in the nucleus, in-situ hybridization of mouse and human testis was carried out. The nuclei of spermatogonia, spermatocytes and round and elongated spermatids were all positively stained. In human spermatocytes, the nuclear staining pattern was fibrillar, suggesting an association of the mitochondrial transcript with the meiotic chromos...
During intercellular communication, cells release extracellular vesicles such as exosomes, which ... more During intercellular communication, cells release extracellular vesicles such as exosomes, which contain proteins, ncRNAs and mRNAs that can influence proliferation and/or trigger apoptosis in recipient cells, and have been proposed to play an essential role in promoting invasion of tumor cells and in the preparation of metastatic niches. Our group proposed the antisense non-coding mitochondrial RNA (ASncmtRNA) as a new target for cancer therapy. ASncmtRNA knockdown using an antisense oligonucleotide (ASO-1537S) causes massive death of tumor cells but not normal cells and strongly reduces metastasis in mice. In this work, we report that exosomes derived from ASO-1537S-treated MDA-MB-231 breast cancer cells (Exo-1537S) inhibits tumorigenesis of recipient cells, in contrast to exosomes derived from control-ASO-treated cells (Exo-C) which, in contrast, enhance these properties. Furthermore, an in vivo murine peritoneal carcinomatosis model showed that Exo-1537S injection reduced tumori...
The family of long noncoding mitochondrial RNAs (ncmtRNAs), comprising sense (SncmtRNA), and anti... more The family of long noncoding mitochondrial RNAs (ncmtRNAs), comprising sense (SncmtRNA), and antisense (ASncmtRNA-1 and ASncmtRNA-2) members, are differentially expressed according to cell proliferative status; SncmtRNA is expressed in all proliferating cells, while ASncmtRNAs are expressed in normal proliferating cells, but is downregulated in tumor cells. ASncmtRNA knockdown with an antisense oligonucleotide induces massive apoptosis in tumor cell lines, without affecting healthy cells. Apoptotic death is preceded by proliferation blockage, suggesting that these transcripts are involved in cell cycle regulation. Here, we show that ASncmtRNA knockdown induces cell death preceded by proliferative blockage in three different human breast cancer cell lines. This effect is mediated by downregulation of the key cell cycle progression factors cyclin B1, cyclin D1, CDK1, CDK4, and survivin, the latter also constituting an essential inhibitor of apoptosis, underlying additionally the onset of apoptosis. The treatment also induces an increase in the microRNA hsa-miR-4485-3p, whose sequence maps to ASncmtRNA-2 and transfection of MDA-MB-231 cells with a mimic of this miRNA induces cyclin B1 and D1 downregulation. Other miRNAs that are upregulated include nuclear-encoded hsa-miR-5096 and hsa-miR-3609, whose mimics downregulate CDK1. Our results suggest that ASncmtRNA targeting blocks tumor cell proliferation through reduction of essential cell cycle proteins, mediated by mitochondrial and nuclear miRNAs. This work adds to the elucidation of the molecular mechanisms behind cell cycle arrest preceding tumor cell apoptosis induced by ASncmtRNA knockdown. As proof-of-concept, we show that in vivo knockdown of ASncmtRNAs results in drastic inhibition of tumor growth in a xenograft model of MDA-MB-231 subcutaneous tumors, further supporting this approach for the development of new therapeutic strategies against breast cancer.
Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity... more Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity (+) in 10/40 (25%) patients versus 27 (65%) patients in postoperative blood (p <0.0001). EpCAM(+) in blood was seen at POD1, POD7 and after 6 weeks in 10 (28.6%), 9 (23.1%) and 8 (23.5%) patients respectively. Preoperative peritoneal lavage fluid was EpCAM(+) in 4 (10.3%) versus 21 (53.8%) patients postoperatively (p < 0.0001). At none of the time-points, an association was found between EpCAM positivity in blood and/or peritoneal cavity and cancer-specific and diseasefree survival. Also, no significant associations were found between clinicopathological variables and perioperative EpCAM positivity. Conclusion: Despite a significant increase in tumor cell counts quantified with real-time RT-PCR for EpCAM, the detection of perioperative tumor cell dissemination does not seem to be associated with worse prognosis in PDAC. [NCT00495924] 611 POSTER Bcl-2 family protein expression in navitoclax-treated patients (pts) with lymphoid malignancies
Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity... more Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity (+) in 10/40 (25%) patients versus 27 (65%) patients in postoperative blood (p <0.0001). EpCAM(+) in blood was seen at POD1, POD7 and after 6 weeks in 10 (28.6%), 9 (23.1%) and 8 (23.5%) patients respectively. Preoperative peritoneal lavage fluid was EpCAM(+) in 4 (10.3%) versus 21 (53.8%) patients postoperatively (p < 0.0001). At none of the time-points, an association was found between EpCAM positivity in blood and/or peritoneal cavity and cancer-specific and diseasefree survival. Also, no significant associations were found between clinicopathological variables and perioperative EpCAM positivity. Conclusion: Despite a significant increase in tumor cell counts quantified with real-time RT-PCR for EpCAM, the detection of perioperative tumor cell dissemination does not seem to be associated with worse prognosis in PDAC. [NCT00495924] 611 POSTER Bcl-2 family protein expression in navitoclax-treated patients (pts) with lymphoid malignancies
Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth... more Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth cause of cancer death in Chile. Human papillomavirus (HPV) is responsible for most cervical cancers. Individuals seeking basic information about HPV frequently turn to health information websites. We hypothesized that some of their data may be inaccurate. Study design: Comparative analysis of information. Methods: We analyze the content of highly accessed websites such as the Spanish version of Wikipedia and Yahoo Answers through the application of a questionnaire, as well as a website managed by the Chilean Ministry of Health (Minsal). The accuracy of each answer was confirmed by comparison with information retrieved from articles published by indexed journals. Results: The information provided by the Spanish version of Wikipedia was accurate; nevertheless a few omissions were detected. The quality of the information provided by the Spanish version of Yahoo Answers was inaccurate and confusing. The Minsal website lacked important information on several topics about HPV even though it is managed and endorsed by the government.
Knockdown of the antisense noncoding mitochondrial RNAs (ASncmtRNAs) induces apoptotic death of s... more Knockdown of the antisense noncoding mitochondrial RNAs (ASncmtRNAs) induces apoptotic death of several human tumor cell lines, but not normal cells, supporting a selective therapy against different types of cancer. In this work, we evaluated the effects of knockdown of ASncmtRNAs on bladder cancer (BCa). We transfected the BCa cell lines UMUC-3, RT4 and T24 with the specific antisense oligonucleotide Andes-1537S, targeted to the human ASncmtRNAs. Knockdown induced a strong inhibition of cell proliferation and increase in cell death in all three cell lines. As observed in UMUC-3 cells, the treatment triggered apoptosis, evidenced by loss of mitochondrial membrane potential and Annexin V staining, along with activation of procaspase-3 and downregulation of the anti-apoptotic factors survivin and Bcl-xL. Treatment also inhibited cell invasion and spheroid formation together with inhibition of N-cadherin and MMP 11. In vivo treatment of subcutaneous xenograft UMUC-3 tumors in NOD/SCID mice with Andes-1537S induced inhibition of tumor growth as compared to saline control. Similarly, treatment of a high-grade bladder cancer PDX with Andes-1537S resulted in a strong inhibition of tumor growth. Our results suggest that ASncmtRNAs could be potent targets for bladder cancer as adjuvant therapy.
Background Extracellular vesicles (EVs) have shown great potential for targeted therapy, as they ... more Background Extracellular vesicles (EVs) have shown great potential for targeted therapy, as they have a natural ability to pass through biological barriers and, depending on their origin, can preferentially accumulate at defined sites, including tumors. Analyzing the potential of EVs to target specific cells remains challenging, considering the unspecific binding of lipophilic tracers to other proteins, the limitations of fluorescence for deep tissue imaging and the effect of external labeling strategies on their natural tropism. In this work, we determined the cell-type specific tropism of B16F10-EVs towards cancer cell and metastatic tumors by using fluorescence analysis and quantitative gold labeling measurements. Surface functionalization of plasmonic gold nanoparticles was used to promote indirect labeling of EVs without affecting size distribution, polydispersity, surface charge, protein markers, cell uptake or in vivo biodistribution. Double-labeled EVs with gold and fluoresc...
According to the American Cancer Society, bladder cancer is the 6th most common cancer in the U.S... more According to the American Cancer Society, bladder cancer is the 6th most common cancer in the U.S. When diagnosed and treated early, the 5 year survival rate is 94%. However, patients with invasive cancer have a much worse prognosis, with a 50% 5-year survival rate.
Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth... more Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth cause of cancer death in Chile. Human papillomavirus (HPV) is responsible for most cervical cancers. Individuals seeking basic information about HPV frequently turn to health information websites. We hypothesized that some of their data may be inaccurate. Study design: Comparative analysis of information. Methods: We analyze the content of highly accessed websites such as the Spanish version of Wikipedia and Yahoo Answers through the application of a questionnaire, as well as a website managed by the Chilean Ministry of Health (Minsal). The accuracy of each answer was confirmed by comparison with information retrieved from articles published by indexed journals. Results: The information provided by the Spanish version of Wikipedia was accurate; nevertheless a few omissions were detected. The quality of the information provided by the Spanish version of Yahoo Answers was inaccurate and confusing. The Minsal website lacked important information on several topics about HPV even though it is managed and endorsed by the government.
Bladder cancer (BC) is the sixth most common cause of cancer; BC risk increases with age and is m... more Bladder cancer (BC) is the sixth most common cause of cancer; BC risk increases with age and is more common among men than women. Upon diagnosis, the 5-year relative survival rate for patients is approximately 77%. The treatment options available for bladder cancer include chemotherapy, radiation therapy, immunotherapy, targeted therapy, and surgery. Despite the advances in therapeutically novel approaches, BC remains an important problem of public health. Long non-coding RNA (lncRNA) is defined as non-protein-coding RNA molecule longer than 200 nucleotides. Recent findings have highlighted that lncRNA contributes to the regulation of multiple signaling pathways in bladder cancer, suggesting that lncRNA exerts its roles during the biological processes of tumorigenesis, tumor proliferation, differentiation, apoptosis, invasion, migration, and stemness. In our laboratory, we described a family of mitochondrial long non-coding RNAs containing stem-loop structures, named sense and antis...
Background We have previously shown a differential expression of a family of mitochondrial ncRNAs... more Background We have previously shown a differential expression of a family of mitochondrial ncRNAs in normal and cancer cells. Normal proliferating cells and cancer cells express the sense mitochondrial ncRNA (SncmtRNA). In addition, while normal proliferating cells express two antisense mitochondrial ncRNAs (ASncmtRNAs-1 and −2), these transcripts seem to be universally down-regulated in cancer cells. In situ hybridization (ISH) of some normal and cancer tissues reveals nuclear localization of these transcripts suggesting that they are exported from mitochondria. Methods FISH and confocal microscopy, in situ digestion with RNase previous to ISH and electron microscopy ISH was employed to confirm the extra-mitochondrial localization of the SncmtRNA and the ASncmtRNAs in normal proliferating and cancer cells of human and mouse. Results In normal human kidney and mouse testis the SncmtRNA and the ASncmtRNAs were found outside the organelle and especially localized in the nucleus associated to heterochromatin. In cancer cells, only the SncmtRNA was expressed and was found associated to heterochromatin and nucleoli. Conclusion The ubiquitous localization of these mitochondrial transcripts in the nucleus suggests that they are new players in the mitochondrial-nuclear communication pathway or retrograde signaling. Down regulation of the ASncmtRNAs seems to be an important step on neoplastic transformation and cancer progression.
Mitochondria are traditionally been viewed as the cell's powerhouse, generating most of its ATP. ... more Mitochondria are traditionally been viewed as the cell's powerhouse, generating most of its ATP. However, besides this fundamental metabolic role, mitochondria are implicated in diverse other processes, including apoptosis, inflammation and metastasis. These functions are exerted in part by the growing class of long noncoding mitochondrial RNAs (lncmtRNAs). We found that normal human proliferating cells express a family of noncoding mitochondrial RNAs (ncmtRNAs), comprised of sense (SncmtRNA) and antisense (ASncmtRNA). However, tumor cells express only sense transcripts, suggesting that ASncmtRNA downregulation as a cancer new hallmark. The few ASncmtRNAs copies in tumor cells seem essential to tumor cell viability: knockdown of these transcripts with antisense oligonucleotides (ASO) causes massive apoptotic death of tumor cells, preceded by cell cycle arrest. Preclinical assays show that systemic administration of ASO delayed tumor growth in melanoma and renal cancer models and, caused total remission in subcutaneous renal cancer tumors. The same treatment, however, does not affect normal tissue, suggesting this approach for the development of an efficient and safe therapeutic strategy for several cancer types.
Objective: Cervical cancer is the second most common cancer in women with high rates of mortality... more Objective: Cervical cancer is the second most common cancer in women with high rates of mortality worldwide. Cervical cancer is slowly progressive and is preceded by pre-invasive intraepithelial lesions. Therefore, detection of premalignant lesions is key to preventing disease progression to advanced stages. The objective of the present study was examination and quantification of the differentially expressed non-coding mitochondrial RNAs during progression of disease. Material and methods: The differential expression of S-ncmtRNA and AS-ncmtRNA was analyzed by in situ hybridization (ISH) using tissue macroarrays (TMA) from normal, CIN1, CIN2, CIN3 and invasive squamous carcinoma (SCC). PCNA and p16INK-4a were detected in consecutive biopsies by immunohistochemistry. Quantification of ISH signal was carried out with Image ProPlus 6.1 software and the results were expressed as percentage of Integrated Optical Density (IOD). Results: We found a marked down-regulation of AS-ncmtRNA in 95% of tissues analyzed (CIN 1/2, CIN 3, and invasive squamous cancer). Moreover, differential expression of ASncmtRNA v/s S-ncmtRNA showed significant difference. Normal proliferating tissues did not display down-regulation of AS-ncmtRNA. Down regulation of AS-ncmtRNA correlated with the expression of the tumor suppressor protein p16INK-4a Conclusions: We found down-regulation of AS-ncmtRNA in pre-malignant and tumor samples which could distinguish normal tissues from early lesions and tumor samples. These results suggest that the down-regulation of AS-ncmtRNA is a novel marker of early lesions and cervix neoplasia.
Background We have previously shown a differential expression of a family of mitochondrial ncRNAs... more Background We have previously shown a differential expression of a family of mitochondrial ncRNAs in normal and cancer cells. Normal proliferating cells and cancer cells express the sense mitochondrial ncRNA (SncmtRNA). In addition, while normal proliferating cells express two antisense mitochondrial ncRNAs (ASncmtRNAs-1 and −2), these transcripts seem to be universally down-regulated in cancer cells. In situ hybridization (ISH) of some normal and cancer tissues reveals nuclear localization of these transcripts suggesting that they are exported from mitochondria. Methods FISH and confocal microscopy, in situ digestion with RNase previous to ISH and electron microscopy ISH was employed to confirm the extra-mitochondrial localization of the SncmtRNA and the ASncmtRNAs in normal proliferating and cancer cells of human and mouse. Results In normal human kidney and mouse testis the SncmtRNA and the ASncmtRNAs were found outside the organelle and especially localized in the nucleus associ...
Amplification of RNA from human sperm heads yielded a fragment of 435 bp that shares 100 % identi... more Amplification of RNA from human sperm heads yielded a fragment of 435 bp that shares 100 % identity with a central region of the 16S mitochondrial rRNA. The nuclear localization in the sperm of the mitochondrial RNA was confirmed by in-situ hybridization. These results, together with the localization of the 16S mitochondrial rRNA in mouse sperm, are the first demonstration that the organelle transcript is a normal component of the mammalian gamete. The possibility that the nuclear mitochondrial RNA arises from nuclear transcription of a mitochondrial pseudogene was ruled out. To determine when during spermatogenesis the mitochondrial RNA is localized in the nucleus, in-situ hybridization of mouse and human testis was carried out. The nuclei of spermatogonia, spermatocytes and round and elongated spermatids were all positively stained. In human spermatocytes, the nuclear staining pattern was fibrillar, suggesting an association of the mitochondrial transcript with the meiotic chromos...
During intercellular communication, cells release extracellular vesicles such as exosomes, which ... more During intercellular communication, cells release extracellular vesicles such as exosomes, which contain proteins, ncRNAs and mRNAs that can influence proliferation and/or trigger apoptosis in recipient cells, and have been proposed to play an essential role in promoting invasion of tumor cells and in the preparation of metastatic niches. Our group proposed the antisense non-coding mitochondrial RNA (ASncmtRNA) as a new target for cancer therapy. ASncmtRNA knockdown using an antisense oligonucleotide (ASO-1537S) causes massive death of tumor cells but not normal cells and strongly reduces metastasis in mice. In this work, we report that exosomes derived from ASO-1537S-treated MDA-MB-231 breast cancer cells (Exo-1537S) inhibits tumorigenesis of recipient cells, in contrast to exosomes derived from control-ASO-treated cells (Exo-C) which, in contrast, enhance these properties. Furthermore, an in vivo murine peritoneal carcinomatosis model showed that Exo-1537S injection reduced tumori...
The family of long noncoding mitochondrial RNAs (ncmtRNAs), comprising sense (SncmtRNA), and anti... more The family of long noncoding mitochondrial RNAs (ncmtRNAs), comprising sense (SncmtRNA), and antisense (ASncmtRNA-1 and ASncmtRNA-2) members, are differentially expressed according to cell proliferative status; SncmtRNA is expressed in all proliferating cells, while ASncmtRNAs are expressed in normal proliferating cells, but is downregulated in tumor cells. ASncmtRNA knockdown with an antisense oligonucleotide induces massive apoptosis in tumor cell lines, without affecting healthy cells. Apoptotic death is preceded by proliferation blockage, suggesting that these transcripts are involved in cell cycle regulation. Here, we show that ASncmtRNA knockdown induces cell death preceded by proliferative blockage in three different human breast cancer cell lines. This effect is mediated by downregulation of the key cell cycle progression factors cyclin B1, cyclin D1, CDK1, CDK4, and survivin, the latter also constituting an essential inhibitor of apoptosis, underlying additionally the onset of apoptosis. The treatment also induces an increase in the microRNA hsa-miR-4485-3p, whose sequence maps to ASncmtRNA-2 and transfection of MDA-MB-231 cells with a mimic of this miRNA induces cyclin B1 and D1 downregulation. Other miRNAs that are upregulated include nuclear-encoded hsa-miR-5096 and hsa-miR-3609, whose mimics downregulate CDK1. Our results suggest that ASncmtRNA targeting blocks tumor cell proliferation through reduction of essential cell cycle proteins, mediated by mitochondrial and nuclear miRNAs. This work adds to the elucidation of the molecular mechanisms behind cell cycle arrest preceding tumor cell apoptosis induced by ASncmtRNA knockdown. As proof-of-concept, we show that in vivo knockdown of ASncmtRNAs results in drastic inhibition of tumor growth in a xenograft model of MDA-MB-231 subcutaneous tumors, further supporting this approach for the development of new therapeutic strategies against breast cancer.
Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity... more Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity (+) in 10/40 (25%) patients versus 27 (65%) patients in postoperative blood (p <0.0001). EpCAM(+) in blood was seen at POD1, POD7 and after 6 weeks in 10 (28.6%), 9 (23.1%) and 8 (23.5%) patients respectively. Preoperative peritoneal lavage fluid was EpCAM(+) in 4 (10.3%) versus 21 (53.8%) patients postoperatively (p < 0.0001). At none of the time-points, an association was found between EpCAM positivity in blood and/or peritoneal cavity and cancer-specific and diseasefree survival. Also, no significant associations were found between clinicopathological variables and perioperative EpCAM positivity. Conclusion: Despite a significant increase in tumor cell counts quantified with real-time RT-PCR for EpCAM, the detection of perioperative tumor cell dissemination does not seem to be associated with worse prognosis in PDAC. [NCT00495924] 611 POSTER Bcl-2 family protein expression in navitoclax-treated patients (pts) with lymphoid malignancies
Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity... more Poster Session-Biomarkers Results: After dichotomization, preoperative blood was EpCAM-positivity (+) in 10/40 (25%) patients versus 27 (65%) patients in postoperative blood (p <0.0001). EpCAM(+) in blood was seen at POD1, POD7 and after 6 weeks in 10 (28.6%), 9 (23.1%) and 8 (23.5%) patients respectively. Preoperative peritoneal lavage fluid was EpCAM(+) in 4 (10.3%) versus 21 (53.8%) patients postoperatively (p < 0.0001). At none of the time-points, an association was found between EpCAM positivity in blood and/or peritoneal cavity and cancer-specific and diseasefree survival. Also, no significant associations were found between clinicopathological variables and perioperative EpCAM positivity. Conclusion: Despite a significant increase in tumor cell counts quantified with real-time RT-PCR for EpCAM, the detection of perioperative tumor cell dissemination does not seem to be associated with worse prognosis in PDAC. [NCT00495924] 611 POSTER Bcl-2 family protein expression in navitoclax-treated patients (pts) with lymphoid malignancies
Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth... more Objectives: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth cause of cancer death in Chile. Human papillomavirus (HPV) is responsible for most cervical cancers. Individuals seeking basic information about HPV frequently turn to health information websites. We hypothesized that some of their data may be inaccurate. Study design: Comparative analysis of information. Methods: We analyze the content of highly accessed websites such as the Spanish version of Wikipedia and Yahoo Answers through the application of a questionnaire, as well as a website managed by the Chilean Ministry of Health (Minsal). The accuracy of each answer was confirmed by comparison with information retrieved from articles published by indexed journals. Results: The information provided by the Spanish version of Wikipedia was accurate; nevertheless a few omissions were detected. The quality of the information provided by the Spanish version of Yahoo Answers was inaccurate and confusing. The Minsal website lacked important information on several topics about HPV even though it is managed and endorsed by the government.
Knockdown of the antisense noncoding mitochondrial RNAs (ASncmtRNAs) induces apoptotic death of s... more Knockdown of the antisense noncoding mitochondrial RNAs (ASncmtRNAs) induces apoptotic death of several human tumor cell lines, but not normal cells, supporting a selective therapy against different types of cancer. In this work, we evaluated the effects of knockdown of ASncmtRNAs on bladder cancer (BCa). We transfected the BCa cell lines UMUC-3, RT4 and T24 with the specific antisense oligonucleotide Andes-1537S, targeted to the human ASncmtRNAs. Knockdown induced a strong inhibition of cell proliferation and increase in cell death in all three cell lines. As observed in UMUC-3 cells, the treatment triggered apoptosis, evidenced by loss of mitochondrial membrane potential and Annexin V staining, along with activation of procaspase-3 and downregulation of the anti-apoptotic factors survivin and Bcl-xL. Treatment also inhibited cell invasion and spheroid formation together with inhibition of N-cadherin and MMP 11. In vivo treatment of subcutaneous xenograft UMUC-3 tumors in NOD/SCID mice with Andes-1537S induced inhibition of tumor growth as compared to saline control. Similarly, treatment of a high-grade bladder cancer PDX with Andes-1537S resulted in a strong inhibition of tumor growth. Our results suggest that ASncmtRNAs could be potent targets for bladder cancer as adjuvant therapy.
Background Extracellular vesicles (EVs) have shown great potential for targeted therapy, as they ... more Background Extracellular vesicles (EVs) have shown great potential for targeted therapy, as they have a natural ability to pass through biological barriers and, depending on their origin, can preferentially accumulate at defined sites, including tumors. Analyzing the potential of EVs to target specific cells remains challenging, considering the unspecific binding of lipophilic tracers to other proteins, the limitations of fluorescence for deep tissue imaging and the effect of external labeling strategies on their natural tropism. In this work, we determined the cell-type specific tropism of B16F10-EVs towards cancer cell and metastatic tumors by using fluorescence analysis and quantitative gold labeling measurements. Surface functionalization of plasmonic gold nanoparticles was used to promote indirect labeling of EVs without affecting size distribution, polydispersity, surface charge, protein markers, cell uptake or in vivo biodistribution. Double-labeled EVs with gold and fluoresc...
According to the American Cancer Society, bladder cancer is the 6th most common cancer in the U.S... more According to the American Cancer Society, bladder cancer is the 6th most common cancer in the U.S. When diagnosed and treated early, the 5 year survival rate is 94%. However, patients with invasive cancer have a much worse prognosis, with a 50% 5-year survival rate.
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Papers by Jaime Villegas