Nanoparticle-Mediated Hyperthermia and Cytotoxicity Mechanisms in Cancer

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Peer Review Report

Manuscript ID: International Journal of Molecular Sciences-2777645

Title: Nanoparticle-mediated Hyperthermia and Cytotoxicity Mechanisms in Cancer

The study “Nanoparticle-mediated Hyperthermia and cytotoxicity mechanisms in Cancer” by authors Bala et al. lies within the Journal scope of International Journal of Molecular Sciences. The study emphasizes on the potential of Hyperthermia and nanotechnology for a targeted tumor treatment. This comprehensive review lacks recent developments which should be added to this very pool of knowledge. We suggested several suggestions for the authors to incorporate before recommending the work for publication. The authors should pay attention to all aspects on the given comments in next submission.

Please provide rebuttal or a point-by-point reply to all given comments below.

Detailed Comments:

Comment #1:

Tumors are heterogeneously perfused as seen under imaging. Discuss the role of blood perfusion heterogeneity of tumors in present context with the recent published study [Modified Pennes bioheat equation with heterogeneous blood perfusion: A newer perspective] under Discussion section elucidating this aspect in detail.

Comment #2:

 In lines 89-90, the authors mentioned that “hyperthermia treatment in tissues generates a series of physiological cell changes”,

In lines 94-96, the authors mentioned that “increased permeability, amplifies the accumulation of fluids and proteins in the tumor microenvironment, leading to a sharp increase of the interstitial fluid pressure”.

however, the reasoning should be better explained. For example, the authors should elaborate and explain that what exactly happens with hyperthermia inside the tumor and more specifically the tumor interstitial space. One recent study by Zhu and colleagues [https://doi.org/10.1007/s11517-020-02308-4], investigates the effect of hyperthermia-induced improvement of hydraulic conductivity and lymphatic function on both tumoral interstitial fluid pressure (IFP) reduction and enhanced nanoparticle delivery to tumor. The implication of IFP reductions causes improvements in the local blood perfusion rates to enhance nanoparticle concentration/deposition in the tumor. Such enhancement is related to the heating-induced structural changes in the extracellular matrix.

Lines 101-102, the authors mentioned that “nanoparticle- mediated HTT has been reported to increase the apoptosis and necrosis of tumor cells due to collagen fiber damage”, however, didn’t explains the governing physics. Under microCT imaging guidance, one recent development [Biological heat and mass transport mechanisms behind nanoparticles migration revealed under microCT image guidance] suggested that nanoparticles migrate and diffuses inside the tumor interstitial space during nanoparticle induced hyperthermia explains the biological heat and mass transport mechanisms that are responsible for such changes. Due to development of thermal damage because of rising temperatures causes an enhancement in tumor porosity (interstitial space). This study must explicitly include that cell-necrosis induced diffusivity change and cell-necrosis induced porosity enhancement may be the two intricate mechanisms that promotes nanoparticle migration and thereby causes apoptosis and necrosis of tumor cells. Also, discuss this issue in Discussion section as well.

Comment #3

 

Lines 184-191:

Only one study was retrieved from our literature review; according to the results, when magnetic Fe3O4 nanoparticles (MNPs) […………….] MNPs concentration dependent [55].

Lines 310-314:

The studies by Zhu and colleagues, performed a series of experiments on PC3 tumors implanted on the flank of healthy mice and designed heating protocols for magnetic nanoparticles induced hyperthermia. Discuss such developments for Prostate Tissue [Heating Protocol Design Affected by Nanoparticle Re-distribution and Thermal Damage Model in Magnetic Nanoparticle Hyperthermia for Cancer Treatment].

Comment #4

For skin tumors, infrared imaging can be used to quantify the abnormality/skin cancer by performing inverse heat transfer to extract parameters needed for a hyperthermia exposure experiments. One study by Zhu and co-workers, covers this very important aspect [Extraction of baseline blood perfusion rates in mouse body and implanted PC3 tumor using infrared images and theoretical simulation].

Comment #5

Discuss the magnetic nanoparticles distribution and re-distribution during hyperthermia using quantitative pixel information obtained from microCT images. The grayscale values can be converted into Hounsfield Units to estimate the Specific Absorption Rates and Concentration Distribution for a given infusion rates [Quantitative Evaluation of Effects of Coupled Temperature Elevation, Thermal Damage, and Enlarged Porosity on Nanoparticle Migration in Tumors during Magnetic Nanoparticle Hyperthermia]. Discuss this issue under discussion section.

Comment #6

Discuss the role of thermal ablation margins [Pre-operative Assessment of Ablation Margins for Variable Blood Perfusion Metrics in a Magnetic Resonance Imaging Based Complex Breast Tumour Anatomy: Simulation Paradigms in Thermal Therapies] and preserving healthy tissues [Incorporating Vascular-stasis Based Blood Perfusion to evaluate the Thermal Signatures of Cell-death using Modified Arrhenius Equation with Regeneration of Living Tissues during Nanoparticle-assisted Thermal Therapy] following a nanoparticle induced thermal ablation and hyperthermia treatments. Include such recent mathematical developments in this important review compiled by authors.

General Comments:

Comment #1: One of the primary concerns with this review paper is the lack of clarity in defining the scope and objectives of the study. The authors have not clearly outlined the specific research questions or goals they aimed to address. As a result, the paper appears to be a collection of loosely connected ideas rather than a cohesive review. 

Comment #2: Another major issue is the lack of rigorous methodology. The paper does not provide any information regarding the systematic search and selection of relevant articles or studies. A comprehensive review should demonstrate a well-defined methodology to ensure the inclusion of relevant and reliable sources.

Comment #3: The review paper also suffers from a lack of critical analysis and evaluation of the reviewed technologies. Merely describing and summarizing the existing technologies without offering any meaningful insights or comparisons diminishes the value of the review. The paper should have critically examined the strengths, limitations, and potential areas of improvement for each technology.

Comment #4: The overall organization and structure of the paper are inadequate. The flow of ideas is unclear, and there is a lack of coherence between sections. The paper should have presented a clear introduction, outlined the main themes or categories of technologies, and provided a concise summary or conclusion to tie the information together.

Comment #5: Irregular spacing (lines 48, 91), inaccurate °C symbol written at lines 64 and 65, “temperature rises evenly” at lines 68.

We are looking forward to receiving your revised Manuscript.

Comments on the Quality of English Language

Spacing issues should be corrected in next submission.

Author Response

Reviewer #1

 

Dear Reviewer 1,

 

I am pleased to submit our revised version. We would like to thank you for your time and comments. The revised document has been uploaded so that you can easily track the changes that were made. Kindly find below, the answer to your comments:

Detailed Comments:

Comment #1:

Tumors are heterogeneously perfused as seen under imaging. Discuss the role of blood perfusion heterogeneity of tumors in present context with the recent published study [Modified Pennes bioheat equation with heterogeneous blood perfusion: A newer perspective] under Discussion section elucidating this aspect in detail. 

Response: Thank you for your comment. Please refer to lines 382-387.

Comment #2:

 In lines 89-90, the authors mentioned that “hyperthermia treatment in tissues generates a series of physiological cell changes”, 

In lines 94-96, the authors mentioned that “increased permeability, amplifies the accumulation of fluids and proteins in the tumor microenvironment, leading to a sharp increase of the interstitial fluid pressure”.

however, the reasoning should be better explained. For example, the authors should elaborate and explain that what exactly happens with hyperthermia inside the tumor and more specifically the tumor interstitial space. One recent study by Zhu and colleagues [https://doi.org/10.1007/s11517-020-02308-4], investigates the effect of hyperthermia-induced improvement of hydraulic conductivity and lymphatic function on both tumoral interstitial fluid pressure (IFP) reduction and enhanced nanoparticle delivery to tumor. The implication of IFP reductions causes improvements in the local blood perfusion rates to enhance nanoparticle concentration/deposition in the tumor. Such enhancement is related to the heating-induced structural changes in the extracellular matrix.

 

Response: Thank you very much for your remarks. We have included the relevant information in lines 114-117: “Hyperthermia can exert structural changes in the extracellular matrix by reducing IFP and enhances hydraulic conductivity and lymphatic drainage. This can increase the blood perfusion, thus  facilitating the intratumoral concentration of NPs [24].”

Lines 101-102, the authors mentioned that “nanoparticle- mediated HTT has been reported to increase the apoptosis and necrosis of tumor cells due to collagen fiber damage”, however, didn’t explains the governing physics. Under microCT imaging guidance, one recent development [Biological heat and mass transport mechanisms behind nanoparticles migration revealed under microCT image guidance] suggested that nanoparticles migrate and diffuses inside the tumor interstitial space during nanoparticle induced hyperthermia explains the biological heat and mass transport mechanisms that are responsible for such changes. Due to development of thermal damage because of rising temperatures causes an enhancement in tumor porosity (interstitial space). This study must explicitly include that cell-necrosis induced diffusivity change and cell-necrosis induced porosity enhancement may be the two intricate mechanisms that promotes nanoparticle migration and thereby causes apoptosis and necrosis of tumor cells. Also, discuss this issue in Discussion section as well.

Response: Thank you very much for your comment.

Using microCT imaging, one recent study offers insight on NPs migration and intra-tumoral distribution during HT treatment. Temperature increase promotes thermal damage and further cell necrosis and apoptosis, that contributes to the expansion of interstitial space. This results in augmented tumor porosity, that facilitates NP redistribution [29]”

Comment #3

Lines 184-191:

Only one study was retrieved from our literature review; according to the results, when magnetic Fe3O4 nanoparticles (MNPs) […………….] MNPs concentration dependent [55].

Lines 310-314:

The studies by Zhu and colleagues, performed a series of experiments on PC3 tumors implanted on the flank of healthy mice and designed heating protocols for magnetic nanoparticles induced hyperthermia. Discuss such developments for Prostate Tissue [Heating Protocol Design Affected by Nanoparticle Re-distribution and Thermal Damage Model in Magnetic Nanoparticle Hyperthermia for Cancer Treatment].

Response: Thank you for your helpful suggestions, we have incorporated them in the manuscript in lines 339-341: “Furthermore, Zhu et. al. used microCT scan blood perfusion rates to evaluate the thermal response and transport mechanism of injected NP-mediated hyperthermia on PC3 tumors, implanted on the flank of healthy mice [105].”

Comment #4

For skin tumors, infrared imaging can be used to quantify the abnormality/skin cancer by performing inverse heat transfer to extract parameters needed for a hyperthermia exposure experiments. One study by Zhu and co-workers, covers this very important aspect [Extraction of baseline blood perfusion rates in mouse body and implanted PC3 tumor using infrared images and theoretical simulation].

Response: Thank you for your comment. Please refer to lines 344-346: “Another recent study investigates the effects of inverse heat transfer, using infrared imaging techniques, on PC3 tumor cells implanted on Balb/c mice [106]. The results from the latter studies may facilitate future experiments by implementing heating variables and intratumoral NP redistribution.”

Comment #5 

Discuss the magnetic nanoparticles distribution and re-distribution during hyperthermia using quantitative pixel information obtained from microCT images. The grayscale values can be converted into Hounsfield Units to estimate the Specific Absorption Rates and Concentration Distribution for a given infusion rates [Quantitative Evaluation of Effects of Coupled Temperature Elevation, Thermal Damage, and Enlarged Porosity on Nanoparticle Migration in Tumors during Magnetic Nanoparticle Hyperthermia]. Discuss this issue under discussion section.

Response: Thank you for your comment. In order to clarify this, we have added lines 392-393 in our manuscript: “It is hypothesized that NP trajectory not only is influenced by heat transfer, but also thermal damage additionally boosts NP re-distribution within the cancerous tumor [114]

Comment #6

Discuss the role of thermal ablation margins [Pre-operative Assessment of Ablation Margins for Variable Blood Perfusion Metrics in a Magnetic Resonance Imaging Based Complex Breast Tumour Anatomy: Simulation Paradigms in Thermal Therapies] and preserving healthy tissues [Incorporating Vascular-stasis Based Blood Perfusion to evaluate the Thermal Signatures of Cell-death using Modified Arrhenius Equation with Regeneration of Living Tissues during Nanoparticle-assisted Thermal Therapy] following a nanoparticle induced thermal ablation and hyperthermia treatments. Include such recent mathematical developments in this important review compiled by authors.

Response: Thank you for your comment. We have added lines 394-399 in our revised manuscript: “Several heating protocols, based on MRI imaging, have studied cancerous tumor blood supply. Those have directly linked heating parameters, such as dosage and duration, in an attempt to avoid harming the surrounding normal cells [115]. Recent mathematical developments integrate bioheat and kinetic models, in order to combine i) tissue regeneration under thermal damage and ii) NP migration, and provide an insight into clinical applications on NP-mediated hyperthermia [116]”

General Comments:

Comment #1: One of the primary concerns with this review paper is the lack of clarity in defining the scope and objectives of the study. The authors have not clearly outlined the specific research questions or goals they aimed to address. As a result, the paper appears to be a collection of loosely connected ideas rather than a cohesive review. 

Response: We would like to thank you for your valuable time and interest towards improving the quality of our work. The aim of our manuscript is to present the results of the existing original research articles, investigating the cytotoxicity mechanisms of nanoparticle-mediated hyperthermia. We sincerely hope that our revised manuscript, after addressing your insightful comments, has become a more cohesive and interesting review of the current literature.

Comment #2: Another major issue is the lack of rigorous methodology. The paper does not provide any information regarding the systematic search and selection of relevant articles or studies. A comprehensive review should demonstrate a well-defined methodology to ensure the inclusion of relevant and reliable sources.

Response: Thank you very much for your comments. Kindly refer to section 2 “Methods and results”.

Comment #3: The review paper also suffers from a lack of critical analysis and evaluation of the reviewed technologies. Merely describing and summarizing the existing technologies without offering any meaningful insights or comparisons diminishes the value of the review. The paper should have critically examined the strengths, limitations, and potential areas of improvement for each technology.

Response: Thank you for your comment. However, a critical evaluation of the technologies used in the experimental studies under discussion in the current work, falls out of the scope of our manuscript. As already discussed, we aimed to summarize and present existing evidence regarding nanoparticle-mediated hyperthermia and cytotoxicity mechanisms. Furthermore, we tried to identify the implications as well as the associated potential of this novel approach for future research, from a clinical aspect. We hope that a critical analysis of the technologies used in nanoparticle-mediated hyperthermia will be addressed in a future review article.

 

Comment #4: The overall organization and structure of the paper are inadequate. The flow of ideas is unclear, and there is a lack of coherence between sections. The paper should have presented a clear introduction, outlined the main themes or categories of technologies, and provided a concise summary or conclusion to tie the information together. 

Response: Thank you for your comment. We sincerely hope that our revised manuscript has become a more pleasant reading experience as a whole.

Comment #5: Irregular spacing (lines 48, 91), inaccurate °C symbol written at lines 64 and 65, “temperature rises evenly” at lines 68.

Response: Thank you for your remarks. Please refer to lines 48, 91, 64, 65 and 68 of our revised manuscript.

 

Reviewer 2 Report

Comments and Suggestions for Authors

Revision report

Article : Nanoparticle-mediated Hyperthermia and cytotoxicity mechanisms in cancer.

 

Dear authors, I consider that your article is very interesting and novel, however, I consider that several aspects could be improved to deepen the problems discussed in your article. Similarly, the complement of your article would allow a better contextual and technical understanding related to the title of your research. Then I suggest the following improvement points for your review article.

1) Improve the introduction: Provide a comprehensive general vision of current challenges in the treatment of cancer and the potential of nanotechnology to address these limitations. He points out the gap in the existing literature that the document aims to address.

 

 

2) The document could benefit from more visual aids, such as diagrams or graphics, to help illustrate the concepts and data present. This is important that visual aids can help readers better understanding information and complex data, and can also make the document easier to read. For example, the document could include diagrams or flow diagrams to illustrate nanoparticle mediated hyperthermia mechanisms and how it is directed to cancer cells. This would help readers visualize the process and better understand the concepts present. In addition, the document could include graphics or graphics that will be presented on the effectiveness of nanoparticle mediated hyperthermia in the objective of cancer cells. This would help readers to see trends and patterns in the data and better understand the implications of the findings. In general, including more visual aids in the document can help increase its clarity and can also improve the impact of current research.

 

3) Discuss the limitations: address the limitations of the study, including possible biases and areas for future research.

 

4) Provide clear implications: Clearly indicate the implications of the findings for future research and clinical practices. Discuss how research contributes to the advancement of cancer treatment strategies.

 

5) Consider ethical and practical considerations: discuss ethical considerations related to the use of nanotechnology in the treatment of cancer and practical implications for its implementation in clinical environments

Comments on the Quality of English Language

Language quality is acceptable

Author Response

Reviewer #2

Dear Reviewer 2,

I am pleased to submit our revised version. We would like to thank you for your time and comments. The revised document has been uploaded so that you can easily track the changes that were made. Kindly find below, the answer to your comments:

• Improve the introduction: Provide a comprehensive general vision of current challenges in the treatment of cancer and the potential of nanotechnology to address these limitations. He points out the gap in the existing literature that the document aims to address.

Response: Thank you very much for your remarks in order to underline the urge for research of additional strategies to effectively improve cancer management. Please refer to Lines 59-62 and lines 39-41.

 2) The document could benefit from more visual aids, such as diagrams or graphics, to help illustrate the concepts and data present. This is important that visual aids can help readers better understanding information and complex data, and can also make the document easier to read. For example, the document could include diagrams or flow diagrams to illustrate nanoparticle mediated hyperthermia mechanisms and how it is directed to cancer cells. This would help readers visualize the process and better understand the concepts present. In addition, the document could include graphics or graphics that will be presented on the effectiveness of nanoparticle mediated hyperthermia in the objective of cancer cells. This would help readers to see trends and patterns in the data and better understand the implications of the findings. In general, including more visual aids in the document can help increase its clarity and can also improve the impact of current research.

Response: Thank you for your helpful suggestions. We have incorporated them in the manuscript by developing Figure 1, regarding nanoparticle-mediated hyperthermia mechanisms and cell mediated apoptosis/necrosis mechanisms.

 3) Discuss the limitations: address the limitations of the study, including possible biases and areas for future research.

Response: Thank you for your comment. Indeed, several limitations were identified during our review (such as different treatment modalities, lack of standardization of the methods performed etc). In section 6 “Future applications and challenges” we have tried to elaborate the existing limitations (highlighted in text, lines 413-414, 431-433, 441-446).

 4) Provide clear implications: Clearly indicate the implications of the findings for future research and clinical practices. Discuss how research contributes to the advancement of cancer treatment strategies.

Response: Thank you for your comment. In accordance with the above, in section 6  “Future applications and challenges” we have highlighted in text (lines 416-417, 420-421, 425-429, 433-436) the implications of current findings that can lead to future research.

5) Consider ethical and practical considerations: discuss ethical considerations related to the use of nanotechnology in the treatment of cancer and practical implications for its implementation in clinical environments

Response: Thank you for your valuable remark. Indeed, several ethical and practical considerations arise from the use of nanotechnology in the treatment of cancer. Besides the challenges already mentioned in lines 424-431, we have added a paragraph in lines 447-453, to further underline such an important aspect.

 

 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Please ensure the sentence structure is correct. Avoid longer sentences and break them into smaller sentences.

Comments on the Quality of English Language

Avoid any technical jargons.

Reviewer 2 Report

Comments and Suggestions for Authors

I have carefully reviewed your manuscript titled "Nanoparticle-mediated Hyperthermia and Cytotoxicity Mechanisms in Cancer". Your thorough attention to addressing reviewers' comments has significantly strengthened the manuscript. In its present form, I consider it suitable for publication, as the revisions effectively enhance its scientific rigor. Congratulations on your dedication to improving the quality of your work.

Comments on the Quality of English Language

Minor editing of English language required